Research activity information

• Oct. 2023 神戸大学農学部六篠会, 六篠論文賞


• Sep. 2018 日本育種学会, 第134回講演会日本育種学会優秀発表賞 (2), Exomeと果実・葉形状にみる日本のウメの多様性

  沼口孝司, 赤木剛士, 北村祐人, 大江孝明, ISHIKAWA RYO, ISHII TAKASHIGE

  Japan society


• Sep. 2018 日本育種学会, 第134回講演会日本育種学会優秀発表賞, ジャポニカ型栽培イネ（日本晴）の非脱粒性に関与する新規遺伝子座の離層形成への効果

  杉山 昇平, 辻村 雄紀, 大塚 宏太郎, Htun, Than Myint, ISHII TAKASHIGE, ISHIKAWA RYO

  Japan society


• Nov. 2017 公益財団法人 農学会, 第16回日本農学進歩賞, 栽培イネの成立に関与した遺伝子の同定と栽培化過程の解明

  ISHIKAWA RYO

  Japan society


• Sep. 2016 日本育種学会, 第130回講演会日本育種学会優秀発表賞, Oryza rufipogonとインディカ型栽培イネ（カサラス）の戻し交雑集団を用いた種子脱粒性に関する新規遺伝子座の探索

  岡 佑美, 竹中 祥尭, 高間 菜摘, 井上 千鶴, Than Myint Htun, 辻村 雄紀, ISHII TAKASHIGE, ISHIKAWA RYO

  Japan society


• Sep. 2014 日本育種学会, 第126回講演会日本育種学会優秀発表賞, 野生イネ(Oryza rufipogon)の遺伝的背景における種子脱粒性遺伝子座間の相互作用と離層形態

  井上 千鶴, Than Myint Htun, INOUE KANAKO, IKEDA KENICHI, ISHII TAKASHIGE, ISHIKAWA RYO

  Japan society


• Mar. 2014 日本育種学会, 第125回講演会日本育種学会優秀発表賞, 野生イネ(Oryza rufipogon)の遺伝的背景における種子脱粒性遺伝子座間の相互作用

  井上 千鶴, Than Myint Htun, ISHII TAKASHIGE, ISHIKAWA RYO

  Japan society

• OlCHR, encoding a chromatin remodeling factor, is a killer causing hybrid sterility between rice species Oryza sativa and O. longistaminata

  Zin Mar Myint, Yohei Koide, Wakana Takanishi, Tomohito Ikegaya, Choi Kwan, Kiwamu Hikichi, Yoshiki Tokuyama, Shuhei Okada, Kazumitsu Onishi, Ryo Ishikawa, Daisuke Fujita, Yoshiyuki Yamagata, Hideo Matsumura, Yuji Kishima, Akira Kanazawa

  May 2024, iScience, English

  [Refereed]

  Scientific journal


• Evaluation of agricultural characteristics among local rice varieties collected more than half-century ago in Indochinese countries

  Sathya Lim, Chhourn Orn, Hiroki Saito, Ryo Ishikawa, Yutaka Sato, Takashige Ishii

  2024, Journal of Crop Research, 69, 1 - 7, English

  [Refereed]

  Scientific journal


• Genetic dissection of a reduced seed-shattering trait acquired in rice domestication

  Ryo Ishikawa

  2024, Breeding Science, 74(4) (4), 285 - 294, English

  [Refereed][Invited]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Wild and cultivated allele effects on rice phenotypic traits in reciprocal backcross populations between Oryza rufipogon and two cultivars, O. sativa Nipponbare and IR36

  Phuong Dang Thai Phan, Akinori Nishimura, Chika Yamamoto, Pham Thien Thanh, Toshihiro Niwa, Yaddehige Priya Jayantha Amarasinghe, Ryo Ishikawa, Takashige Ishii

  Japanese Society of Breeding, Sep. 2023, Breeding Science, 73(4) (4), 373 - 381, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Genome-Wide Association Study Detects Loci Involved in Scab Susceptibility in Japanese Apricot

  Koji Numaguchi, Tomoaki Kashiwamoto, Ryo Ishikawa, Takashige Ishii, Yuto Kitamura

  Aug. 2023, Horticulturae, 9(8) (8), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Detection of novel loci involved in non-seed-shattering behaviour of an indica rice cultivar, Oryza sativa IR36.

  Shohei Sugiyama, Motoki Sakuta, Yuki Tsujimura, Yudai Yamaguchi, Than Myint Htun, Chizuru Inoue, Koji Numaguchi, Takashige Ishii, Ryo Ishikawa

  Asian rice (Oryza sativa) was domesticated from O. rufipogon, and reduced seed-shattering behaviour was selected to increase yields. Two seed-shattering loci, qSH3 and sh4, are involved in reducing seed shattering in both japonica and indica rice cultivars, while qSH1 and qCSS3 are likely specific to japonica cultivars. In indica cultivars, qSH3 and sh4 fail to explain the degree of seed shattering, as an introgression line (IL) of O. rufipogon W630 carrying domesticated alleles at qSH3 and sh4 still showed seed shattering. Here we analysed differences in seed-shattering degree between the IL and the indica cultivar IR36. The values for grain detachment in the segregating population between the IL and IR36 were continuous. Based on QTL-seq analysis using the BC1F2 population between the IL and IR36, we detected two novel loci, qCSS2 and qCSS7 (QTLs for the Control of Seed Shattering in rice on chromosomes 2 and 7), which contributed to the reduced seed shattering in IR36. We further investigated the genetic interaction of qCSS2 and qCSS7 under the presence of qSH3 and sh4 mutations in O. rufipogon W630 and found that IL carrying IR36 chromosomal segments covering all four loci are required to explain seed-shattering degree in IR36. Since qCSS2 and qCSS7 were not detected in previous studies on seed shattering in japonica, their control may be specific to indica cultivars. Therefore, they are important to understanding the history of rice domestication as well as to adjusting the seed-shattering degree of indica cultivars to maximise their yield.

  Corresponding, May 2023, Molecular Genetics and Genomics, English, International magazine

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Variations in grain traits among local rice varieties collected more than half-century ago in Indochinese countries.

  Sathya Lim, Anna Onoda, Chhourn Orn, Hiromu Iwamoto, Ryo Ishikawa, Hiroki Saito, Yutaka Sato, Takashige Ishii

  More than half-century ago, local rice varieties were collected from Indochinese countries (Cambodia, Thailand, Laos, and Vietnam). Of these, 162 local varieties were examined for 7 grain-size traits: seed length/width/thickness, brown rice length/width/thickness, and 100-seed weight. Since these traits varied considerably, a survey of functional mutations was performed in the genes related to these traits. In total, 19 markers (12 InDel and 7 dCAPS markers) were used to investigate the mutations at 14 grain-size loci of GW2, GS2, qLGY3, GS3, GL3.1, TGW3, GS5, GW5, GS6, TGW6, GW6a, GLW7, GL7, and GW8. Significant allele effects were observed with six markers detecting base substitution mutations at GW2 and GS3 and insertion/deletion mutations at GS5, GW5, and GW6a, suggesting that these mutations might have affected the grain trait and caused variation among local varieties in the Indochinese countries. In addition to grain size, the hull color, grain color, and glutinosity were also examined using a survey of loss-of-function mutations at major responsible loci. Most phenotypes were reflected based on functional mutations at these loci. Since the local varieties have wide genetic variation, they are important genetic resources for future rice breeding.

  Dec. 2022, Plants (Basel, Switzerland), 12(1) (1), 133, English, International magazine

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• A stepwise route to domesticate rice by controlling seed shattering and panicle shape.

  Ryo Ishikawa, Cristina Cobo Castillo, Than Myint Htun, Koji Numaguchi, Kazuya Inoue, Yumi Oka, Miki Ogasawara, Shohei Sugiyama, Natsumi Takama, Chhourn Orn, Chizuru Inoue, Ken-Ichi Nonomura, Robin Allaby, Dorian Q Fuller, Takashige Ishii

  Asian rice (Oryza sativa L.) is consumed by more than half of the world's population. Despite its global importance, the process of early rice domestication remains unclear. During domestication, wild rice (Oryza rufipogon Griff.) acquired non-seed-shattering behavior, allowing humans to increase grain yield. Previous studies argued that a reduction in seed shattering triggered by the sh4 mutation led to increased yield during rice domestication, but our experiments using wild introgression lines show that the domesticated sh4 allele alone is insufficient for shattering loss in O. rufipogon. The interruption of abscission layer formation requires both sh4 and qSH3 mutations, demonstrating that the selection of shattering loss in wild rice was not as simple as previously suggested. Here we identified a causal single-nucleotide polymorphism at qSH3 within the seed-shattering gene OsSh1, which is conserved in indica and japonica subspecies but absent in the circum-aus group of rice. Through harvest experiments, we further demonstrated that seed shattering alone did not significantly impact yield; rather, yield increases were observed with closed panicle formation controlled by SPR3 and further augmented by nonshattering, conferred by integration of sh4 and qSH3 alleles. Complementary manipulation of panicle shape and seed shattering results in a mechanically stable panicle structure. We propose a stepwise route for the earliest phase of rice domestication, wherein selection of visible SPR3-controlled closed panicle morphology was instrumental in the sequential recruitment of sh4 and qSH3, which together led to the loss of shattering.

  Jun. 2022, Proceedings of the National Academy of Sciences of the United States of America, 119(26) (26), e2121692119, English, International magazine

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Role of qGZn9a in controlling grain zinc concentration in rice, Oryza sativa L.

  Miki Ogasawara, Naoya Miyazaki, Gotaro Monden, Kenta Taniko, Sathya Lim, Masahide Iwata, Takashige Ishii, Jian Feng Ma, Ryo Ishikawa

  Corresponding, Sep. 2021, Theoretical and Applied Genetics, 134(9) (9), 3013 - 3022, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• The role of wild rice (Oryza rufipogon) awns in seed dispersal

  Yaddehige P.J. Amarasinghe, Mitsuharu Otsuka, Sathya Lim, Ryo Ishikawa, Takashige Ishii

  Cultivated rice (Oryza sativa L.) was domesticated from the Asian wild species O. rufipogon. Compared with cultivated rice, wild rice has spikelets/seeds with long barbed awns. In order to evaluate the role of awns in wild rice, four seed groups with different awn lengths (full, half, quarter and no awns) were prepared, and the following seed dispersal movements were investigated under simulated natural conditions as observed in the tropical Asian habitat: (1) seed detachment from the parent plant; (2) falling angle of mature seed; (3) ability to slip into small spaces; (4) horizontal movement on the ground and (5) horizontal movement in water. As a result, awns were found to enhance the detachment of matured seeds from the panicles in the initial seed dispersal step. They regulated vertical orientation in the air, and the vertical form may enable seeds to squeeze to the ground. The awned seeds also showed advantages in horizontal movements on the ground and in the water. In most of the experiments, seeds with full awns showed the best performance for seed dispersal, suggesting that wild rice keeps long awns to survive under natural conditions. Since seed awning is dominantly controlled by wild functional alleles at several loci, wild rice may be able to prevent a drastic reduction of awn length.

  Cambridge University Press (CUP), Dec. 2020, Seed Science Research, 30(4) (4), 319 - 324

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Evaluation of domestication loci associated with awnlessness in cultivated rice, Oryza sativa

  Yaddehige Priya Jayantha Amarasinghe, Rie Kuwata, Akinori Nishimura, Phuong Dang Thai Phan, Ryo Ishikawa, Takashige Ishii

  BACKGROUND: Awns are bristle-like organs at the tips of the glumes. Wild rice has maintained long awns for successful seed propagation through seed dispersal. Seed awning is an interesting trait in rice domestication. Long awns might have been beneficial for seed gatherers in the initial phase of domestication; however, awnless phenotypes were preferably selected in a later phase with non-seed-shattering plants. Investigation of domestication loci associated with awnlessness in cultivated rice will be useful in clarifying the process and history of rice domestication. RESULTS: Quantitative trait locus (QTL) analysis for seed awning was carried out using a BC3F2 population between Oryza sativa IR36 (a cultivated donor parent with awnless phenotype) and O. rufipogon W630 (a wild recurrent parent with awns). As a result, two QTLs on chromosome 4 (corresponding to An-1 and LABA1) and one on chromosome 2 (designated as qAWNL2) were detected. Gene interaction among three seed-awning QTLs were further examined with the plants having eight different combinations of homozygous genotypes. Their awn length variation indicated that the IR36 alleles at these loci had the additive awnlessness effects in the genetic background of wild rice. The shortest awn length was observed for the plants having IR36 homozygous alleles at all loci, giving about 75% reduction in awn length. By the fine mapping, the candidate region of the novel qAWNL2 locus was delimited in a 157.4-kb region containing 22 predicted genes in Nipponbare genome. CONCLUSIONS: QTL analysis revealed that three loci, An-1, LABA1 and qAWNL2, were mainly responsible for the awnlessness of O. sativa IR36. In the wild genetic background, loss-of-function alleles at three awning loci showed additive effects on length reduction. In rice domestication, awnless forms may be gradually generated through the accumulation of mutations at awning loci.

  Springer Science and Business Media LLC, Dec. 2020, Rice, 13(1) (1), 26 - 26, English, International magazine

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Interspecific introgression and natural selection in the evolution of Japanese apricot ( Prunus mume )

  Koji Numaguchi, Takashi Akagi, Yuto Kitamura, Ryo Ishikawa, Takashige Ishii

  Domestication and population differentiation in crops involve considerable phenotypic changes. The logs of these evolutionary paths, including natural/artificial selection, can be found in the genomes of the current populations. However, these profiles have been little studied in tree crops, which have specific characters, such as long generation time and clonal propagation, maintaining high levels of heterozygosity. We conducted exon-targeted resequencing of 129 genomes in the genus Prunus, mainly Japanese apricot (Prunus mume), and apricot (Prunus armeniaca), plum (Prunus salicina), and peach (Prunus persica). Based on their genome-wide single-nucleotide polymorphisms merged with published resequencing data of 79 Chinese P. mume cultivars, we inferred complete and ongoing population differentiation in P. mume. Sliding window characterization of the indexes for genetic differentiation identified interspecific fragment introgressions between P. mume and related species (plum and apricot). These regions often exhibited strong selective sweeps formed in the paths of establishment or formation of substructures of P. mume, suggesting that P. mume has frequently imported advantageous genes from other species in the subgenus Prunus as adaptive evolution. These findings shed light on the complicated nature of adaptive evolution in a tree crop that has undergone interspecific exchange of genome fragments with natural/artificial selections.

  Wiley, Nov. 2020, Plant Journal, 104(6) (6), 1551 - 1567, English, International magazine

  [Refereed]

  Scientific journal


• Genetic evaluation of domestication-related traits in rice: implications for the archaeobotany of rice origins

  Ryo Ishikawa, Cristina C. Castillo, Dorian Q. Fuller

  Springer Science and Business Media {LLC}, Aug. 2020, Archaeological and Anthropological Sciences, 12(8) (8), English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Estimation of demographic history of Japanese and Taiwanese populations in Prunus mume using SSR marker genotypes

  Koji Numaguchi, Yuto Kitamura, Ryo Ishikawa, Takashige Ishii

  Prunus mume Sieb. et Zucc. (conventionally called Japanese apricot, Chinese mei and mume) is a deciduous fruit tree species in the genus Prunus. More than 300 P. mume cultivars are distributed mainly in East Asia, including Japanese fruit, small-fruit and ornamental cultivars and Taiwanese cultivars. In order to estimate demographic history of three Japanese and one Taiwanese subpopulations, approximate Bayesian computation analysis was carried out using 20 SSR genotype datasets of 53 cultivars (20 fruit, 8 small-fruit, 20 ornamental and 5 Taiwanese cultivars). At first, the best fitting model (posterior probability: 0.501) was estimated among six probable scenarios, and median values of demographic parameters were computed. The generation time for P. mume cultivars was assumed to be seven years (full reproductive age) for time conversion. In the best scenario, Japanese and Taiwanese populations had first diverged at 10360 (95% confidence interval (CI): 2079-56910) years ago, followed by the separation of ornamental cultivars among Japanese populations at 3633 (95% CI: 1218-12740) years ago, and final differentiation between fruit and small-fruit cultivars at 2387 (95% CI: 623-6258) years ago. Although the divergence times were roughly estimated, the results suggest that Japanese and Taiwanese populations were separated through the geographic isolation with different climate conditions, and ornamental, fruit and small-fruit cultivars were recently differentiated based on human preference in Japan.

  The Society of Crop Science and Breeding in Kinki, Japan, 2020, Journal of Crop Research, 65, 31 - 35, English

  [Refereed]


• Arabidopsis FLL2 promotes liquid-liquid phase separation of polyadenylation complexes.

  Fang X, Wang L, Ishikawa R, Li Y, Fiedler M, Liu F, Calder G, Rowan B, Weigel D, Li P, Dean C

  Lead, May 2019, Nature, 569, 265 - 269, English

  [Refereed]

  Scientific journal


• Spikelet opening under controlled transpiration conditions in rice

  Funa Ogawa, Ryo Ishikawa, Takashige Ishii

  In rice, spikelet opening is an important process for anthesis to produce seeds. Spikelet opening is greatly affected by temperature, humidity, light, and physical stress. To clarify the important factors for spikelet opening, flowering panicles of Japonica cultivar Nipponbare were observed under four controlled transpiration conditions designated as submergence, shower, oil and high-humidity conditions. The submergence condition was designed to allow transpiration only from panicles. Other three conditions were designed to suppress transpiration from panicles by water, oil and high humidity. For each condition, four panicles with 15 spikelets were prepared, and flowering ratios were recorded on the following afternoon. The examination was repeated for three days, and the averages were compared. Under the submergence condition, many flowered spikelets were observed with the average value of 83.3%. On the other hand, a few or no spikelets flowered in the panicles under the shower (17.8%) and oil conditions (0.6%). Almost half of the spikelets (46.1%) flowered under the high-humidity condition. These average values were all significantly lower than the controls (ca. 92%) without any treatments. These results indicate that transpiration from lemma and palea is necessary to have spikelet opening. In addition, spikelet opening time was observed using a wild accession of O. rufipogon to examine whether transpiration from an awn (a tip organ of the lemma) is associated with flowering time or not. Eight panicles of three wild plants were prepared, and awns of the spikelets were alternatively cut based on the primary branch order. The plants were put outside under the sun, and the exact opening time was recorded in minutes for all the spikelets flowered on the following morning. As a result, average opening times for awned and awnless spikelets were not significantly different to each other. Since opening time was not associated with transpiration from the awns, a precise switch for panicle opening may synchronize with transpiration from the surface of the lemma and/or palea.

  The Society of Crop Science and Breeding in Kinki, Japan, 2019, Journal of Crop Research, 64, 31 - 35, English

  [Refereed]

  Scientific journal


• QTL analysis for awnlessness using a backcross population between Oryza rufipogon and O. sativa IR36

  Yaddehige P, J. Amarasinghe, Rie Kuwata, Ryo Ishikawa, Takashige Ishii

  Long seed awning in wild rice is one of the propagation-related traits in natural habitats. During rice domestication, plants with shorter awns may gradually be selected because long awns disturb seed harvesting and handling. To clarify the domestication process of awnless rice, we first produced 146 backcross recombinant inbred lines at BC₂F₇ generation between Oryza rufipogon W630 (a recurrent parent) and O. sativa IR36 (a donor parent). Of these, a single line of G5 having shortest awns was selected. The G5 backcross recombinant inbred line was found to have IR36 homozygous alleles at 20 out of 167 SSR marker loci, showing seven IR36 chromosomal segments in the wild genetic background. The G5 line was further crossed with W630, and 160 BC₃F₂ progenies were generated. They were planted in the paddy field, and QTL analysis for awnlessness was carried out using awn length data at 5th spikelet position. As a result, one minor QTL and two major QTLs were detected on chromosomes 2 and 4, respectively. According to the associated marker positions, two major QTLs on chromosome 4 seem to be identical to An-1 and LABA1 loci, and the QTL on chromosome 2 may be a novel locus. Although these QTLs explained most of the awn length difference between O. rufipogon W630 and the G5 line, some other minor loci for awnlessness may still exist in the genome of awnless IR36.

  The Society of Crop Science and Breeding in Kinki, Japan, 2019, Journal of Crop Research, 64, 43 - 46, English

  [Refereed]

  Scientific journal


• Microsatellite Marker Development and Population Structure Analysis in Japanese Apricot (Prunus mume Sieb. et Zucc.)

  Koji Numaguchi, Shogo Ishio, Yuto Kitamura, Kentaro Nakamura, Ryo Ishikawa, Takashige Ishii

  Japanese Society for Horticultural Science, 2019, The Horticulture Journal, 88(2) (2), 222 - 231, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Detection of a novel locus involved in non-seed-shattering behaviour of Japonica rice cultivar, Oryza sativa 'Nipponbare'

  Yuki Tsujimura, Shohei Sugiyama, Kotaro Otsuka, Than Myint Htun, Koji Numaguchi, Cristina Castillo, Takashi Akagi, Takashige Ishii, Ryo Ishikawa

  Corresponding, Springer Science and Business Media LLC, 2019, Theoretical and Applied Genetics, 132(9) (9), 2615 - 2623, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Domestication loci controlling panicle shape, seed shattering, and seed awning

  Takashige Ishii, Ryo Ishikawa

  Springer Singapore, Mar. 2018, Rice Genomics, Genetics and Breeding, 207 - 221, English

  [Refereed]

  In book


• Detection of quantitative trait loci controlling grain zinc concentration using Australian wild rice, Oryza meridionalis, a potential genetic resource for biofortification of rice

  Ryo Ishikawa, Masahide Iwata, Kenta Taniko, Gotaro Monden, Naoya Miyazaki, Chhourn Orn, Yuki Tsujimura, Shusaku Yoshida, Jian Feng Ma, Takashige Ishii

  Oct. 2017, Plos One, 12(10) (10), e0187224, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Estimation of loci involved in non-shattering of seeds in early rice domestication

  Ryo Ishikawa, Akinori Nishimura, Than Myint Htun, Ryo Nishioka, Yumi Oka, Yuki Tsujimura, Chizuru Inoue, Takashige Ishii

  Apr. 2017, Genetica, 145(2) (2), 201 - 207, English

  [Refereed]

  Scientific journal


• Gene interaction at seed-awning loci in the genetic background of wild rice

  Mai Ikemoto, Mitsuharu Otsuka, Pham Thien Thanh, Phuong Dang Thai Phan, Ryo Ishikawa, Takashige Ishii

  Feb. 2017, Genes & Genetic Systems, 92(1) (1), 21 - 26, English

  [Refereed]

  Scientific journal


• Development of Near-Isogenic lines for shattering habit by crossing japonica rice cultivars with different grain-shattering traits and the genetic analysis of the shattering habit

  Kazuo Okubo, Chizuru Inoue, Yuki Tsujimura, Ryo Ishikawa

  Crop Science Society of Japan, 2017, Japanese Journal of Crop Science, 86(4) (4), 358 - 366, Chinese

  [Refereed]

  Scientific journal


• Investigation of genetic loci controlling non-shattering behaviour in an Indica rice cultivar ‘IR36’. Journal of Crop Research 62: 19-23.

  Yuki Tsujimura, Chizuru Inoue, Than Mynt Htun, Yumi Oka, Takashige Ishii, Ryo Ishikawa

  Asian cultivated rice Oryza sativa L. has been known to be domesticated from wild rice, O. rufipogon. During domestication, agronomically suitable traits were selected, including a loss of seed shattering. In previous studies, three quantitative trait loci (QTLs), sh4, qSH1, and qSH3, were found to be involved in the non-shattering behaviour of O. sativa Japonica ‘Nipponbare’. In contrast, O. sativa Indica ‘IR36’ has cultivated alleles at sh4 and qSH3, but a partial abscission layer formation has been observed. Differences in the seed-shattering degree between Japonica and Indica rice are mainly accounted for by the genotypes at qSH1. However, the allele effects at the loci controlling the non-shattering behaviour of Indica rice are not known clearly. We previously produced an introgression line (IL) carrying O. sativa Japonica ‘Nipponbare’ cultivated alleles at sh4 and qSH3 in the genetic background of wild rice O. rufipogon W630. Although this introgression line (hereafter IL(3+4)) has the same genotypes at sh4 and qSH3 as O. sativa Indica ‘IR36’, it has a well-formed abscission layer compared to that of IR36, resulting in very easy-shattering like wild rice. To understand the independent effects of sh4 and qSH3 on non-shattering behaviour of ‘IR36’, we evaluated the F₁ and F₂ plants between ‘IR36’ and IL(3+4). In F₁ plants, the formation of a clear abscission layer was observed in a manner similar to that of IL(3+4), suggesting that ‘IR36’ may harbour recessive allele(s) at unidentified seed-shattering loci. We also observed the segregation of seed-shattering behaviour in the F₂ population, confirming that other unknown mutation(s) may underlie the non-shattering behaviour of ‘IR36’.

  Corresponding, The Society of Crop Science and Breeding in Kinki, Japan, 2017, Journal of Crop Research, 62, 19 - 23, English

  [Refereed]

  Scientific journal


• Identification of quantitative trait loci controlling floral morphology of rice using a backcross population between common cultivated rice, Oryza sativa and Asian wild rice, O. rufipogon

  Ryo Ishikawa, Takafumi Watabe, Ryo Nishioka, Pham Tien Thanh, Takashige Ishii

  Differences in floral morphologies affect pollination behaviour in many flowering plants. In the genus Oryza, several differences in the size of floral organs are known. In this study, we focused on the differences in the size of floral organs between common cultivated rice, Oryza sativa L. and its wild ancestor, O. rufipogon. We compared floral morphologies between cultivated rice O. sativa cv. Nipponbare and O. rufipogon W630. We first evaluated temporal changes in filament and anther lengths. W630 had longer filaments with rapid elongation within 15 min after spikelet opening. W630 also had longer anthers than Nipponbare, and size of anther was consistent throughout all time examined. We also analysed other six floral traits, and found that W630 had higher stigma and style length, as well as lemma and palea length, but lower lemma and palea width. Quantitative trait locus (QTL) analysis was performed to identify the loci controlling these floral traits, using backcross recombinant inbred lines derived from a cross between Nipponbare and W630. A total of 11 significant QTLs were identified. Of these, two pairs of QTLs for lemma and palea length and one pair for lemma and palea width overlapped, suggesting that common genetic factors may be the reason for the differences in these traits. In addition, we performed QTL analysis for grain size, and found that QTLs for grain size coincided with those for lemma and palea size, indicating that grain size is partly controlled by glume capacity. The QTLs identified in this study will be informative for understanding genetic changes associated with rice domestication.

  Lead, Scientific Research Publishing, 2017, American Journal of Plant Science, 8, 734 - 744, English

  [Refereed]

  Scientific journal

  Link to Kobe Univ. Repository (Kernel)


• Genetic survey of genomic regions responsible for panicle spreading in wild rice, Oryza rufipogon

  Ryo Nishioka, Hiromi Mikazuki, Than Myint Htun, Ryo Ishikawa, Takashige Ishii

  Rice (Oryza sativa L.) is derived from the Asian common wild rice, O. rufipogon. In the early stage of domestication, panicle shape may be a key trait before the emergence of plants with non-seed shattering, because wild plants with cultivated-like type of closed panicles were observed to reduce seed shattering through seed retention. Previously, we identified a major locus for this trait to be SPR3 on chromosome 4, controlling gene expression of OsLG1. However, we also found some experimental lines, i.e., BC₂F₈ backcross recombinant inbred lines between O. sativa Nipponbare and O. rufipogon W630, that showed open panicles without wild alleles at SPR3. In this study, a line of AsN136 was selected from them in order to survey new genomic regions responsible for panicle spreading in wild rice. The AsN136 had wild homozygous alleles at 27 out of 180 SSR marker loci, showing nine wild chromosomal segments in the genetic background of Nipponbare. This line was crossed with Nipponbare, and the segregating population consisted of 150 BC₃F₂ plants were produced. They were planted in the paddy field, and their panicle shape was examined based on the observation of the rachisbranch junctions. QTL analysis for panicle shape was carried out with their marker genotype data at 27 SSR loci. As a result, two putative loci were detected on chromosomes 5 and 11, explaining 37.6% and 4.9% of the total phenotypic variance, respectively. The putative locus on chromosome 5 with stronger effect was further examined by the progeny test using BC₃F₃ plants. The results indicated that a new factor for panicle shape was located in the region of RM421-RM274. Expression analysis on OsLG1 and fine mapping of the new locus on chromosome 5 may give good clues to clarify the gene mechanism of panicle spreading.

  The Society of Crop Science and Breeding in Kinki, Japan, 2016, Journal of Crop Research, 61, 23 - 26, English

  [Refereed]

  Scientific journal


• Evaluation of shooting and rooting ability from nodes and ratooning ability using backcross recombinant inbred lines between Oryza rufipogon and O. sativa

  Mai Ikemoto, Tetsuya Ohyagi, Pham Thien Thanh, Ryo Ishikawa, Takashige Ishii

  Annual and perennial differentiation in rice has been one of the major concerns for rice geneticists and ecologists. Among the traits related to reproductive systems, shooting and rooting ability from the nodes and ratooning ability were focused in this study. They were evaluated using backcross recombinant inbred lines (BRILs) between a perennial cultivar of Oryza sativa Nipponbare and an annual accession of O. rufipogon W630. Firstly, five pairs of first and second nodes from the top were collected from each BRIL plant before and after maturing stages. They were half-dipped in water for three weeks and shoot and root generation was observed. From the first nodes, few BRIL plants produced shoots at both stages, whereas most of them generated shoots from the second nodes. Rooting ability was not well observed for the first nodes of the BRILs after maturing, but almost half of their first nodes produced roots before maturing. From the second nodes, many BRILs generated roots at both stages. Continuous frequency distributions in the BRILs were observed for the shooting and rooting ability from the second nodes after maturing. Based on these data, QTL analysis was carried out, however, no significant loci were detected. Environmental factors such as water temperature might affect the evaluation of the traits. Secondly, ratooning ability was examined with another set of BRILs. About 60 days after heading, the percentages of ratoon numbers relative to total number of productive tillers were examined in the field. They were used for QTL analysis for ratooning ability, and one QTL was detected in the region of RM25-RM44 on chromosome 8 with LOD score of 4.2. Chromosome segment substitution analysis on the putative region will be needed to confirm the QTL location.

  The Society of Crop Science and Breeding in Kinki, Japan, 2016, Journal of Crop Research, 61, 13 - 17, English

  [Refereed]

  Scientific journal


• Evaluation of genetic variation among wild rice populations in Cambodia

  Chhourn Orn, Rieko Shishido, Masahiro Akimoto, Ryo Ishikawa, Than Myint Htun, Ken-Ichi Nonomura, Yohei Koide, Men Sarom, Seng Vang, Sakhan Sophany, Ouk Makara, Takashige Ishii

  Dec. 2015, Breeding Science, 65(5) (5), 430 - 437, English

  [Refereed]

  Scientific journal


• Inhibition of abscission layer formation by an interaction of two seed-shattering loci, sh4 and qSH3, in rice

  Chizuru Inoue, Than Myint Htun, Kanako Inoue, Ken-ichi Ikeda, Takashige Ishii, Ryo Ishikawa

  Corresponding, Feb. 2015, Genes & Genetic Systems, 90(1) (1), 1 - 9, English

  [Refereed]

  Scientific journal


• Rice SNF2 family helicase ENL1 is essential for syncytial endosperm development

  Tomomi Hara, Hirokazu Katoh, Daisuke Ogawa, Yasuaki Kagaya, Yutaka Sato, Hidemi Kitano, Yasuo Nagato, Ryo Ishikawa, Akemi Ono, Tetsu Kinoshita, Shin Takeda, Tsukaho Hattori

  Jan. 2015, Plant Journal, 81(1) (1), 1 - 12, English

  [Refereed]

  Scientific journal


• Effect of quantitative trait loci for seed shattering on abscission layer formation in Asian wild rice Oryza rufipogon

  Than Myint Htun, Chizuru Inoue, Orn Chhourn, Takashige Ishii, Ryo Ishikawa

  Corresponding, Sep. 2014, Breeding Science, 64(3) (3), 199 - 205, English

  [Refereed]

  Scientific journal


• Evaluation of genetic variation among rice local and modern varieties in Cambodia

  Orn Chhourn, Ryo Ishikawa, Sakhan Sophany, Ouk Makara, Takashige Ishii

  Genetic variation among rice varieties in Cambodia was evaluated using 276 local and 60 modern varieties. The local varieties were collected more than 50 years ago, and they were classified into four groups (floating rice, rice in dry regions, common non-glutinous rice, glutinous rice). The modern varieties consisted of 35 domestic and 25 foreign lines. Their total DNA samples were extracted and analysed with 12 SSR markers across 12 rice chromosomes. Based on the gene diversity values, genetic variation within group was investigated. Similar levels of genetic variation were observed in four local variety groups, and the overall gene diversity value for 276 local varieties was 0.55. As for modern varieties, lower gene diversity value (0.46) was observed for 35 modern domestic varieties that were generated in Cambodia. The decrease of genetic variation in Cambodianorigin modern varieties may be due to the genetic reduction by modern plant breeding and the social condition changes. However, the overall gene diversity in 60 modern varieties (including 25 foreign varieties) was 0.61, indicating that the high level of genetic variation in Cambodian modern varieties has been maintained by the heterogeneous composition of domestic and foreign varieties. Genetic differentiation among four local and one domestic modern groups were evaluated based on Nei's genetic distances. The lowest value (0.09) was detected between non-glutinous rice and modern domestic groups, suggesting that modern domestic lines were mainly originated from local non-glutinous varieties. High genetic distance values (0.32-0.51) were observed between floating rice and other four. This suggests that deep-water ecosystem might have enhanced the specific diversification of floating rice varieties.

  The Society of Crop Science and Breeding in Kinki, Japan, 2014, Journal of Crop research, 59, 37 - 41, English

  [Refereed]

  Scientific journal


• OsLG1 regulates a closed panicle trait in domesticated rice

  Takashige Ishii, Koji Numaguchi, Kotaro Miura, Kentaro Yoshida, Pham Thien Thanh, Than Myint Htun, Masanori Yamasaki, Norio Komeda, Takashi Matsumoto, Ryohei Terauchi, Ryo Ishikawa, Motoyuki Ashikari

  Apr. 2013, Nature Genetics, 45(4) (4), 462 - 465, English

  [Refereed]

  Scientific journal


• The role of DNA methylation in plants

  Kenji Osabe, Taku Sasaki, Ryo Ishikawa, Ryo Fujimoto

  Nova Science Publishers, Inc., Feb. 2013, DNA Methylation: Principles, Mechanisms and Challenges, 35 - 66, English

  In book


• Estimation of the outcrossing rate for annual Asian wild rice under field conditions

  Phuong Dang Thai Phan, Hiroki Kageyama, Ryo Ishikawa, Takashige Ishii

  Sep. 2012, Breeding Science, 62(3) (3), 256 - 262, English

  [Refereed]

  Scientific journal


• Molecular Mechanisms of Epigenetic Variation in Plants

  Ryo Fujimoto, Taku Sasaki, Ryo Ishikawa, Kenji Osabe, Takahiro Kawanabe, Elizabeth S. Dennis

  Aug. 2012, International Journal of Molecular Sciences, 13(8) (8), 9900 - 9922, English

  [Refereed]


• Multiple Mechanisms and Challenges for the Application of Allopolyploidy in Plants

  Kenji Osabe, Takahiro Kawanabe, Taku Sasaki, Ryo Ishikawa, Keiichi Okazaki, Elizabeth S. Dennis, Tomohiko Kazama, Ryo Fujimoto

  Jul. 2012, International Journal of Molecular Sciences, 13(7) (7), 8696 - 8721, English

  [Refereed]


• Evaluation of Genetic Variation Among Wild Populations and Local Varieties of Rice

  Takashige Ishii, Takashi Hiraoka, Tomoyuki Kanzaki, Masahiro Akimoto, Rieko Shishido, Ryo Ishikawa

  Dec. 2011, Rice, 4(3-4) (3-4), 170 - 177, English

  [Refereed]

  Scientific journal


• Phytochrome B regulates Heading date 1 (Hd1)-mediated expression of rice florigen Hd3a and critical day length in rice

  Ryo Ishikawa, Mayumi Aoki, Ken-ichi Kurotani, Shuji Yokoi, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  Jun. 2011, Molecular Genetics and Genomics, 285(6) (6), 461 - 470, English

  [Refereed]

  Scientific journal


• Rice interspecies hybrids show precocious or delayed developmental transitions in the endosperm without change to the rate of syncytial nuclear division

  Ryo Ishikawa, Takayuki Ohnishi, Yuki Kinoshita, Mitsugu Eiguchi, Nori Kurata, Tetsu Kinoshita

  Mar. 2011, Plant Journal, 65(5) (5), 798 - 806, English

  [Refereed]

  Scientific journal


• Development of backcross recombinant inbred lines between Oryza sativa Nipponbare and O. rufipogon and QTL detection on drought tolerance

  Pham Thien Thanh, Phuong Dang Thai Phan, Naoki Mori, Ryo Ishikawa, Takashige Ishii

  Mar. 2011, Breeding Science, 61(1) (1), 76 - 79, English

  [Refereed]

  Scientific journal


• Temporal changes of seed shattering degree of substitution lines having non-shattering alleles from cultivated rice (Oryza sativa) in the genetic background of wild rice (O. rufipogon)

  Than Myint Htun, Takashige Ishii, Ryo Ishikawa

  Seed shattering is important for wild plant species to guarantee efficient seed propagation. In rice, two shattering loci, sh4 and qSH1, with strong effects on seed shattering were previously identified through the map-based approach. In this study, a rice cultivar, Oryza sativa Japonica cv. Nipponbare, and an annual wild accession, O. rufipogon W630 were used as plant materials. The former contains non-functional alleles at sh4 and qSH1, whereas the latter has shattering alleles at both loci. Since the ancient humans selected non-shattering mutants in the past, it is important to evaluate shattering behavior of plants carrying non-functional alleles in the genetic background of wild rice. Therefore, O. sativa cv. Nipponbare was backcrossed twice with O. rufipogon, and backcross plants at BC₂ generation were produced. Among them, the substitution plants having both cultivated alleles at sh4 and qSH1 loci in the genetic background of wild rice were selected by dCAPS and microsatellite markers. Using these lines and the parents, the temporal changes of shattering degree after flowering were examined based on the breaking tensile strength values for detachment of seeds from the pedicels. At 5 days after flowering, the shattering degrees of the substitution lines were almost similar to that of wild accession. They decreased moderately but maintained around half values of cultivated Nipponbare at 10 days after pollination. Probably, partial formation of abscission layers in pedicels might allow matured seeds to be kept on the panicles. These results suggest that the wild rice may still keep additional gene(s) promoting the formation of abscission layer besides qSH1 and sh4 alleles.

  Corresponding, The Society of Crop Science and Breeding in Kinki, Japan, 2011, Journal of Crop research, 56, 39 - 44, English

  [Refereed]

  Scientific journal


• QTL analysis for submergence avoidance using backcross recombinant inbred lines between Oryza sativa and O. rufipogon.

  Phuong Dang, Thai Phan, Pham Thien Thanh, Naoki Mori, Ryo Ishikawa, Takashige Ishii

  Backcross populations are useful for evaluating the agronomic traits from unadapted germplasms. In this study, we produced 159 and 170 backcross recombinant inbred lines (BRILs) at the BC₂F₈ generation between Oryza sativa Japonica Nipponbare (a recurrent parent) and O. rufipogon W630 and between O. sativa Indica IR36 (a recurrent parent) and O. rufipogon W630, respectively. These BRILs were found to have nearly homozygous genome constitutions based on the marker genotypes at SSR loci covering whole chromosomes. Since their selfed progenies have almost identical genotypes in each line, the simple test tube method was applied for BRILs (BC₂F₉ generation) to evaluate the ability of fast shoot elongation after germination stage under submerged condition. Then, QTL analysis of submergence avoidance was carried out with marker genotype data. As a result, three (on chromosomes 2, 3 and 10) and two QTLs (on chromosomes 3 and 4) were found in the BRILs having genetic backgrounds of Nipponbare and IR36, respectively. Of these, one each had the wild allele with increasing effect on shoot length. These favorable wild alleles would be useful in improving direct-seeding cultivation in water-prone areas.

  The Society of Crop Science and Breeding in Kinki, Japan, 2011, Journal of Crop research, 56, 45 - 49, English

  [Refereed]

  Scientific journal


• QTL analysis for flowering time using backcross population between Oryza sativa Nipponbare and O. rufipogon

  Pham Thien Thanh, Phuong Dang Thai Phan, Ryo Ishikawa, Takashige Ishii

  Aug. 2010, Genes & Genetic Systems, 85(4) (4), 273 - 279, English

  [Refereed]

  Scientific journal


• Allelic interaction at seed-shattering loci in the genetic backgrounds of wild and cultivated rice species

  Ryo Ishikawa, Pham Thien Thanh, Naoto Nimura, Than Myint Htun, Masanori Yamasaki, Takashige Ishii

  Lead, Aug. 2010, Genes & Genetic Systems, 85(4) (4), 265 - 271, English

  [Refereed]

  Scientific journal


• エピジェネティクスが制御する植物の形質

  藤本 龍, ISHIKAWA RYO

  遺伝子の発現情報の伝達は塩基配列に依存するジェネティックな遺伝と塩基配列によらず、遺伝子の修飾状態の変化に依存するエピジェネティックな遺伝が存在する．植物のエピジェネティクス研究は、モデル植物であるシロイヌナズナで進んでおり、特に突然変異体を用いた解析がこの分野の進展に大きく貢献している．動物のエピジェネティックな制御に関連する遺伝子の突然変異体は、致死に到ることが多いが、植物の突然変異体では致死に到らず、遺伝学的な解析が可能であることが理由として挙げられる．また、エピジェネティックな遺伝子の発現制御は、遺伝子機能・環境応答・生殖制御などとの関連性が示唆されていることからも育種において重要な研究課題である．本総説では、育種学的観点からエピジェネティックな制御機構の重要性について、トランスポゾン・生殖・環境応答の項目に分けて概説し、またエピジェネティックな現象による重要農業形質の例について最近の話題を交えて紹介する．

  日本育種学会, 2010, 育種学研究, 12(4) (4), 123 - 131, Japanese

  [Refereed]


• Epigenetic programming: The challenge to species hybridization

  Ryo Ishikawa, Tetsu Kinoshita

  Jul. 2009, Molecular Plant, 2(4) (4), 589 - 599, English

  [Refereed][Invited]


• Phytochrome dependent quantitative control of Hd3a transcription is the basis of the night break effect in rice flowering

  Ryo Ishikawa, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  Lead, Apr. 2009, Genes & Genetic Systems, 84(2) (2), 179 - 184, English

  [Refereed]

  Scientific journal


• Evaluation of genetic diversity among rice local varieties in Vietnam

  Takashi Hiraoka, Nobuyuki Ikeda, Ryo Ishikawa, Takashige Ishii

  近畿作物・育種研究会, 2009, Journal of Crop Research, 54, 125 - 130, English

  [Refereed]

  Scientific journal


• Genomic imprinting: A balance between antagonistic roles of parental chromosomes

  Tetsu Kinoshita, Yoko Ikeda, Ryo Ishikawa

  Dec. 2008, Seminars in Cell and Developmental Biology, 19(6) (6), 574 - 579, English

  [Refereed][Invited]


• Molecular basis of night break effect on the photoperiodic control of flowering in rice

  Ishikawa R, Yokoi S, Shimamoto K

  Lead, 8, Jul. 2006, Tanpakushitsu kakusan koso. Protein, nucleic acid, enzyme., 51(8) (8), 933 - 942, Japanese

  [Refereed]


• 野生イネの種子脱粒性、穂の開帳性、頴の色を支配する遺伝子のマッピング

  ISHII TAKASHIGE, 崎山 弘樹, ISHIKAWA RYO, 上島 脩志

  2006, 近畿作育研究, 51, 23 - 26, Japanese

  [Refereed]

  Scientific journal


• Suppression of the floral activator Hd3a is the principal cause of the night break effect in rice

  Ryo Ishikawa, Shyojiro Tamaki, Shuji Yokoi, Noritoshi Inagaki, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  Lead, Dec. 2005, Plant Cell, 17(12) (12), 3326 - 3336, English

  [Refereed]

  Scientific journal

• Toward increasing grain zinc concentration in rice

  片岡 仁史, 石川 亮

  Last, Apr. 2025, アグリバイオ, 9(4) (4), 58 - 59, Japanese

  [Invited]

  Introduction other


• いいね！やせいいね2！

  小出陽平, 藤田大輔, 石川亮, 山形悦透, 塩野克宏, 清水元樹, 殿崎薫, 吉川貴徳

  Mar. 2025, 育種学研究, Japanese

  [Invited]

  Introduction scientific journal


• The attraction of genus Oryza

  Ishikawa Ryo, Yamagata Yoshiyuki, Koide Yohei, Ishii Takashige, Ishikawa Ryuji, Akimoto Masahiro, Tsuda Katsutoshi, Fujita Daisuke

  Lead, Japanese Society of Breeding, 2023, Breeding Research, 25(1) (1), 50 - 54, Japanese

  [Invited]

  Introduction scientific journal


• Detection of novel locus involved in non-seed-shattering behavior of cultivated rice using wild rice accession

  石川亮, 松田暢啓, 辻村雄紀

  Lead, Jul. 2020, アグリバイオ, 4(7) (7), 91 - 92, Japanese

  [Invited]

  Introduction other


• Evaluation of genetic diversity by resequencing of a diversity panel of African rice (Oryza glaberrima)

  平尾愛喜, 藤田大輔, 石川亮, 小出陽平, 安井秀, 山形悦透

  2020, 育種学研究, 22


• Utility of Oryza meridionalis in rice breeding: increasing grain zinc concentration

  宮崎直哉, 石川亮

  Last, Jan. 2019, アグリバイオ, 3(1) (1), 45 - 46, Japanese

  [Invited]

  Introduction other


• 熱帯アジアにおける栽培イネから野生イネへの遺伝子流動について

  谷尾侑香, ORN Chhourn, 秋本正博, 宍戸理恵子, HTUN Than Myint, PHAN Phuong, Dang Thai, 野々村賢一, 小出陽平, 石川亮, 石井尊生

  22 Sep. 2018, 育種学研究, 20, 131, Japanese


• オーストラリアの野生イネOryza meridionalisを利用したイネ種子亜鉛濃度を向上させる遺伝子座の検出

  ISHIKAWA RYO

  2018, NBRP RICE Newsletter, 1, 5 - 6, Japanese

  [Invited]

  Introduction other


• イネの種子脱粒性制御機構の解明 : アジアにおける新品種育成を目指して

  石川 亮

  日揮・実吉奨学会, 2017, 研究助成金受給者研究報告集, 36, 44 - 48, Japanese


• 野生イネと栽培イネの間で検出されたアルミニウムストレス耐性を支配する遺伝子座qAl1の遺伝学的解析

  和田もりえ, 岩田将英, 横正健剛, 吉田周作, THANH Pham Thien, 石井尊生, MA J, 石川亮

  21 Mar. 2016, 育種学研究, 18, 202, Japanese


• Recommendation for "Ppd-1 is a key regulator of inflorescence architecture and paired spikelet development in wheat."

  Ryo Ishikawa

  The F1000.com, Mar. 2015, F1000 Prime, 1, English

  [Refereed][Invited]

  Book review


• Recommendation for "Identification of a novel salt tolerance gene in wild soybean by whole-genome sequencing"

  Ryo Ishikawa

  Using a whole-genome-sequencing approach to explore germplasm resources can serve as an important strategy for crop improvement, especially in investigating wild accessions that may contain useful genetic resources that have been lost during the domestication process. Here we sequence and assemble a draft genome of wild soybean and construct a recombinant inbred population for genotyping-by-sequencing and phenotypic analyses to identify multiple QTLs relevant to traits of interest in agriculture. We use a combination of de novo sequencing data from this work and our previous germplasm re-sequencing data to identify a novel ion transporter gene, GmCHX1, and relate its sequence alterations to salt tolerance. Rapid gain-of-function tests show the protective effects of GmCHX1 towards salt stress. This combination of whole-genome de novo sequencing, high-density-marker QTL mapping by re-sequencing and functional analyses can serve as an effective strategy to unveil novel genomic information in wild soybean to facilitate crop improvement.

  The F1000.com, Jul. 2014, F1000 Prime, 5, 4340 - 4340, English, International magazine

  [Refereed][Invited]

  Book review


• Recommendation for "Hd16, a gene for casein kinase I, is involved in the control of rice flowering time by modulating the day-length response"

  Ryo Ishikawa

  Oct. 2013, F1000 Prime, 76(1) (1), 36 - 46, English

  [Refereed][Invited]

  Book review


• Recommendation for "From many, one: genetic control of prolificacy during maize domestication"

  Ryo Ishikawa

  The F1000.com, Oct. 2013, F1000 Prime, 9(6) (6), English

  [Refereed][Invited]

  Book review


• フィトクロムによるHd1を介したフロリゲン遺伝子Hd3aの転写制御と日長認識機構

  石川亮, 青木麻由美, 黒谷賢一, 横井修司, 篠村知子, 高野誠, 島本功

  29 Mar. 2011, 育種学研究, 13, 273, Japanese


• ENDOSPERMLESS1 encodes an SNF2-like helicase essential for endosperm development in rice

  Katoh Hirokazu, Hara Tomomi, Sato Yutaka, Kitano Hidemi, Nagato Yasuo, Ishikawa Ryo, Kinoshita Tetsu, Takeda Shin, Hattori Tsukaho

  The rice enl1 mutant bears seeds without endosperm. We mapped the enl1 locus at a region close to the telomere of the Chromosome 4 long arm and identified a deletion of several nucleotides and substitutions in an exon of a predicted gene in this region. Transgenic introduction of a wild type genomic fragment containing this gene completely complemented the mutant phenotype, concluding this gene to be ENL1. ENL1 encodes a protein belonging to the SNF2 class helicase family, which harbors an SNF2 domain and a HELICc domain. Orthologs of ENL1 are conserved among most of eukaryotes. The human ortholog, PICH, is reported to be required for chromosome condensation, chromosome arm architecture, and sister chromatid segregation. Laser confocal microscopic observation of PI-stained syncytial endosperms revealed the presence of giant endosperm nuclei with many nucleoli in the mutant. The abnormality of mutant nuclei appeared to derive from failure in chromosome separation. These results suggest that the errors in the chromosome cycle at the syncytial stage in the enl1 mutant result in the inability of further endosperm development.

  The Japanese Society of Plant Physiologists, 2011, Plant and Cell Physiology Supplement, 2011, 0060 - 0060


• Evaluation of seed-shattering degree of substitution lines having two non-shattering loci from cultivated rice (Oryza sativa) in the genetic background of wild rice (O. rufipogon)

  Ishikawa Ryo, Htun Than Myint, Yamasaki Masanori, Thanh Pham Thien, Ishii Takashige

  It is known that the common cultivated rice, Oryza sativa, was domesticated from Asian wild rice, O. rufipogon. Loss of seed-shattering is one of the most important traits during rice domestication. In order to better understand the genetic control of seed shattering, chromosome segment substitution lines were prepared by introgressing non-shattering qSH1 and sh4 alleles from cultivated rice, O. sativa cv. Nipponbare, in the genetic background of wild rice. The degree of shattering was examined to evaluate the genetic interaction of two loci. The results showed that the backcross plants individually having Nipponbare homozygous alleles at either shattering locus (qSH1 or sh4) shed all the seeds. These results indicated that two cultivated non-shattering alleles were not sufficient to express full non-shattering behavior in the genetic background of wild rice. Probably some other minor loci are still involved in the control of seed-shattering in wild rice.

  The Japanese Society of Plant Physiologists, 2011, Plant and Cell Physiology Supplement, 2011, 0037 - 0037


• Abnormal development observed in the hybrid endosperm between cultivated and wild rice

  Ishikawa Ryo, Eiguchi Mitsugu, Shinzaki Yuki, Kurata Nori, Kinoshita Tetsu

  Abnormal endosperm development is observed in inter-specific or inter-ploidy crosses of many plant species. Several reports suggested that the endosperm failure is caused either by promotion or suppression of the endosperm development and this can be due to the functional difference between parental genomes. One of the possible molecular mechanisms underlying this phenomenon can be genomic imprinting, an epigenetic mechanism with parent-of-origin dependent mono-allelic gene expression.
  We conducted inter-specific crosses between several cultivated and wild rice species and found abnormality in hybrid endosperm. In these crosses, the rate of nuclear division of the endosperm was not affected but the timing of cellularization was found to be delayed or advanced. We also carried out the microarray analysis using hybrid endosperm of O. sativa and O. longistaminata, and identified the candidate genes related to the endosperm failure. Possible involvement of these genes and their effects on the endosperm development will be discussed.

  The Japanese Society of Plant Physiologists, 2009, Plant and Cell Physiology Supplement, 2009, 0114 - 0114


• イネの胚乳における生殖隔離機構とゲノムインプリンティング

  石川亮, 永口貢, 池田陽子, 倉田のり, 木下哲

  Defect of the endosperm development is observed in inter-specific crosses of many plant species. Abnormal endosperm development causes seed abortion, therefore, this phenomenon is known to be a reproductive barrier after fertilization. Several reports suggested that defect of endosperm development is caused by the functional difference between parental genome. One of the possible molecular mechanisms underlying this phenomenon can be genomic imprinting, an epigenetic mechanism resulting in mono-allelic gene expression by parent-of-origin dependent manner. Recent advances of the study of genomic imprinting in Arabidopsis are applied to understand the reproductive barrier of hybrid endosperm in rice.
  To begin with, we analyzed how imprinted genes are involved in the development of hybrid endosperm. We conducted inter-specific cross between cultivated and wild rice and observed developmental defect in the hybrid endosperm. We also investigated the expression of imprinted gene. Possible involvement of genomic imprinting in the hybrid endosperm will be presented.

  The Japanese Society of Plant Physiologists, 15 Mar. 2008, 日本植物生理学会年会要旨集, 49th, 225 - 0488, Japanese


• ポリコーム複合体による植物の発生制御

  木下 哲, 池田 陽子, ISHIKAWA RYO

  植物の発生過程では,発生のフェイズに応じて様々なセットの遺伝子発現が必要となる.例えば,花を咲かせるフェイズ(生殖成長相)では, AGAMOUS, PISTILATA等の様々なホメオティック遺伝子の発現が必要であるが,これらの遺伝子は栄養成長のフェイズ(栄養成長相)においては必ずしも必要ではない.また,種子形成に必要な遺伝子群も,他の発生過程では発現が抑制されている必要がある.シロイヌナズナの突然変異体の解析から,これらの遺伝子の発現抑制に関与するポリコームグループ(PcG)タンパク質の役割が明らかになっている.PcGタンパク質は進化的に保存された複合体を形成し,ショウジョウバエやヒトではヒストンH3の27番目のリジンをメチル化する活性を持つ. PcG複合体によるヒストン修飾が,細胞分裂を通じた遺伝子の発現抑制に重要であると考えられている.本稿では,シロイメナズナの解析から明らかになってきた,PcG複合体による植物の発生制御を概説する.

  The Japanese Society for Chemical Regulation of Plants, 2008, 植物の生長調節, 43(1) (1), 29 - 34, Japanese

  [Refereed][Invited]

  Introduction commerce magazine


• Role of phytochrome on the photoperiodic control of flowering in rice

  Ryo Ishikawa, Mayumi Aoki, Ken-ichi Kurotani, Hisayo Shimizu, Shuji Yokoi, Noritoshi Inagaki, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  2007, PLANT AND CELL PHYSIOLOGY, 48, S112 - S112, English

  Summary international conference


• イネコアコレクションを用いた開花関連遺伝子の多様性の解明

  高橋靖幸, 石川亮, 横井修司, 島本功

  2006, 日本植物生理学会年会要旨集, 47th


• イネの光中断における光質とフィトクロムの役割

  石川亮, 篠村知子, 七夕高也, 清水久代, 稲垣言要, 高野誠, 島本功

  2006, 日本植物生理学会年会要旨集, 47th


• ～温故知新～ 光中断の実験から植物の光周性による開花の分子機構に迫る

  ISHIKAWA RYO, 横井 修司, 島本 功

  2006, 蛋白質 核酸 酵素, 551, 993 - 942, Japanese

  [Refereed][Invited]

  Introduction commerce magazine


• イネの光中断におけるフィトクロムの役割

  石川亮, 高橋靖幸, 石塚徹, 横井修司, 稲垣言要, 篠村知子, 高野誠

  2005, 日本植物生理学会年会要旨集, 46th


• Molecular genetic approach for the search of florigen; Rice as an example

  K Shimamoto, S Tamaki, R Komiya, S Matsuo, R Ishikawa, M Ikeda, M Abe, K Kurotani, S Yokoi

  2005, PLANT AND CELL PHYSIOLOGY, 46, S11 - S11, English

  Summary international conference


• 短日植物イネの開花を制御する遺伝子ネットワーク

  横井修司, 石川亮, 玉置祥二郎, 松尾祥一, 阿部誠, 小宮玲奈, 黒谷賢一, 島本功

  2005, 日本分子生物学会年会講演要旨集, 28th


• 分子遺伝学的な方法論での探索-短日植物イネでの研究例

  島本功, 玉置祥二郎, 小宮怜奈, 松尾祥一, 石川亮, 池田美香, 阿部誠, 黒谷賢一, 横井修司

  2005, 日本植物生理学会年会要旨集, 46th


• イネの開花制御における光中断の遺伝子発現に与える影響

  石川亮, 横井修司, 島本功

  2004, 日本植物生理学会年会要旨集, 45th


• A gene network of rice which determines photoperiodic regulation of flowering

  Shimamoto Ko, Ishikawa Ryo, Abe Makoto, Tamaki Shojiro, Hayama Ryosuke, Izawa Takeshi, Yokoi Shuji

  The molecular genetic analysis of Arabidopsis thaliana, a long-day (LD) plant, has identified a number of genes required for the photoperiodic control of flowering. However, very little is known about the molecular mechanisms of short-day plants. We studied rice to understand how the photoperiodic control of flowering is regulated in an SD plant. Over-expression of OsGI, a homolog of the Arabidopsis GIGANTEA (GI) gene in transgenic rice, caused late flowering under both SD and LD conditions. Expression of the rice homolog of the Arabidopsis CONSTANS (CO) gene was increased in the transgenic rice, while expression of the rice homolog of FLOWERING LOCUS T (FT) was suppressed. These results indicate that three key regulatory genes for the photoperiodic control of flowering are conserved between Arabidopsisand rice but regulation of the FT gene by CO was reversed, resulting in suppression of flowering in rice under LD conditions.

  The Japanese Society of Plant Physiologists, 2003, Plant and Cell Physiology Supplement, 2003, S40 - S40


• 植物の開花における短日・長日性はどうして決められるか

  島本功, 玉置祥二郎, 石川亮, 阿部誠, 池上顕子, 横井修司

  2003, 日本発生生物学会大会発表要旨集, 36th


• Mapping of genes for shattering habit from Asian wild rice (O.rufipogon)

  ISHIKAWA R., KAMIJIMA O., ISHII T.

  30 Mar. 2002, 育種学研究 = Breeding research, 4(1) (1), 70 - 70, Japanese

• アフロ・ユーラシアの考古植物学

  ISHIKAWA RYO, 杉山昇平, 辻村雄紀, 沼口孝司, クリスティーナ・コボ・カスティヨ, 石井尊生

  Others, クバプロ, May 2019, Japanese

  Scholarly book


• Rice Genomics, Genetics and Breeding - Domestication loci controlling panicle shape, seed shattering and seed awning

  Takashige Ishii, Ryo Ishikawa

  Others, Springer, 2018, English

  Scholarly book


• DNA methylation; principles, mechanisms and challenges

  Kenji Osabe, Taku Sasaki, Ryo Ishikawa, Ryo Fujimoto

  Others, Nova Science, 2012, English

  Scholarly book

• Target capture法に基づく日本と中国のウメの集団構造および系統関係について

  沼口孝司, 赤木剛士, 北村祐人, ISHIKAWA RYO, ISHII TAKASHIGE

  園芸学会 平成30年度秋季大会, Mar. 2019, Japanese, 園芸学会, 明治大学, Domestic conference

  Oral presentation


• QTL analysis for awnlessness using a backcross population between Oryza rufipogon and O. sativa IR36

  Priya J.A. Yaddehige, Rie Kuwata, Ryo Ishikawa, Takashige Ishii

  近畿作物・育種研究会 第186回例会, Nov. 2018, English, 近畿作物・育種研究会, 京都大学, Domestic conference

  Oral presentation


• 野生イネOryza meridionalisを用いて同定されたイネ種子亜鉛濃度を支配するqGZn9は連鎖した２つの遺伝子座によって制御される

  宮崎直哉, 谷古健太, 岩田将英, 門田剛太郎, Orn Chhourn, 吉田周作, ISHII TAKASHIGE, 馬建鋒, ISHIKAWA RYO

  日本育種学会第134回講演会, Sep. 2018, Japanese, 日本育種学会, 岡山大学, Domestic conference

  Oral presentation


• 穂の開帳性が栽培イネ(Oryza sativa)の穂形態に与える影響について

  窪田芳生, 西岡諒, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第134回講演会, Sep. 2018, Japanese, 日本育種学会, 岡山大学, Domestic conference

  Poster presentation


• 熱帯アジアにおける栽培イネから野生イネへの遺伝子流動について

  谷尾侑香, Chhourn Orn, 秋本正博, 宍戸理恵子, Than Myint Htun, Phuong Dang, Thai Phan, 野々村賢一, 小出陽平, ISHIKAWA RYO, 石井尊生

  日本育種学会第134回講演会, Sep. 2018, Japanese, 日本育種学会, 岡山大学, Domestic conference

  Poster presentation


• ジャポニカ型栽培イネ（日本晴）の非脱粒性に関与する新規遺伝子座の離層形成への効果

  杉山昇平, 辻村雄紀, 大塚宏太郎, Than Myint Htun, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第134回講演会, Sep. 2018, Japanese, 日本育種学会, 岡山大学, Domestic conference

  Oral presentation


• イネ育種における野生イネ利用の可能性

  ISHIKAWA RYO, 宮崎直哉, 杉山昇平, 窪田芳生, 馬建鋒, ISHII TAKASHIGE

  日本育種学会第134回講演会, Sep. 2018, Japanese, 日本育種学会, 岡山大学, Domestic conference

  Nominated symposium


• Exomeと果実・葉形状にみる日本のウメの多様性

  沼口孝司, 赤木剛士, 北村祐人, 大江孝明, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第134回講演会, Sep. 2018, Japanese, 日本育種学会, 岡山大学, Domestic conference

  Oral presentation


• Evaluation of the domestication-related traits in rice: plant genetics meets archaeobotany

  Ryo Ishikawa

  International Workshop: Current Frontiers in the Archaeobotany of Rice, Aug. 2018, English, Center for the Study of Chinese Archaeology, Peking University, International conference

  [Invited]

  Invited oral presentation


• 野生イネOryza rufipogon における種子脱粒性遺伝子座間の相互作用

  杉山昇平, Cristina Castillo, 岡佑美, Than Myint Htun, 野々村賢一, ISHII TAKASHIGE, ISHIKAWA RYO

  イネ遺伝学・分子生物学ワークショップ2018, Jul. 2018, Japanese, 国立遺伝学研究所, Domestic conference

  Poster presentation


• オーストラリア由来の野生イネOryza meridionalis を用いたイネ種子亜鉛濃度を支配する遺伝子座の同定

  宮崎直哉, 谷古健太, 岩田将英, 門田剛太郎, Orn Chhourn, 吉田周作, ISHII TAKASHIGE, 馬建鋒, ISHIKAWA RYO

  イネ遺伝学・分子生物学ワークショップ2018, Jul. 2018, Japanese, 国立遺伝学研究所, Domestic conference

  Poster presentation


• イネにおける小穂の開花メカニズムの解明に向けて

  小川風和, ISHIKAWA RYO, ISHII TAKASHIGE

  近畿作物・育種研究会 第185回例会, Jun. 2018, Japanese, 近畿作物・育種研究会, 神戸大学, Domestic conference

  Oral presentation


• ジャポニカ型栽培イネOryza sativa 日本晴の非脱粒性に関与する新規遺伝子座の同定

  辻村雄紀, Than Myint Htun, 沼口孝司, 高間菜摘, 杉山昇平, ISHII TAKASHIGE, ISHIKAWA RYO

  第59回日本植物生理学会年会, Mar. 2018, Japanese, 植物生理学会, 札幌コンベンションセンター, Domestic conference

  Poster presentation


• Evaluation of the domestication-related traits in rice: plant genetics meets archaeobotany

  Ryo Ishikawa

  New trends in Afro-Euraasian archaeobotany, Jan. 2018, English, Nara Palace Site Museum (Nara National Research Institute for Cultural Properties), International conference

  [Invited]

  Invited oral presentation


• 野生イネの繁殖に必須の種子脱粒性に関わる遺伝子座の同定

  辻村雄紀, Than Myint Htun, 沼口孝司, 高間菜摘, 杉山昇平, ISHII TAKASHIGE, ISHIKAWA RYO

  第49回種生物学シンポジウム, Dec. 2017, Japanese, 種生物学会, すかっとランド九頭竜, Domestic conference

  Poster presentation


• 野生イネOryza rufipogonと栽培イネOryza sativaの交雑系統群を利用した新規Na+ 輸送系遺伝子・変異の探索

  堀内智貴, ISHIKAWA RYO, 田野井慶太朗, 小林奈通子, ISHII TAKASHIGE, 堀江智明

  日本育種学会第132回講演会, Oct. 2017, Japanese, 日本育種学会, 岩手大学, Domestic conference

  Oral presentation


• ウメ遺伝資源における収穫期および果実形質の多様性

  沼口孝司, 北村祐人, 仲慶晃, 大江孝明, 土田靖久, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第132回講演会, Oct. 2017, Japanese, 日本育種学会, 岩手大学, Domestic conference

  Oral presentation


• embryoless変異体を用いたイネの胚・胚乳サイズ比率制御機構の解析

  金川真実, 松本和也, ISHIKAWA RYO, 伊藤純一, 桧原健一郎

  日本育種学会第132回講演会, Oct. 2017, Japanese, 日本育種学会, 岩手大学, Domestic conference

  Oral presentation


• ウメ黒星病抵抗性に関与するQTLの同定に向けて

  沼口孝司, 北村祐人, ISHIKAWA RYO, ISHII TAKASHIGE

  園芸学会 平成29年度秋季大会, Sep. 2017, Japanese, 園芸学会, 酪農学園大学, Domestic conference

  Oral presentation


• 栽培イネと野生イネの戻し交雑系統群を用いたイネの花器官を支配する遺伝子座の同定

  ISHIKAWA RYO, 渡部 貴史, 西岡 諒, Pham Thien Thanh, ISHII TAKASHIGE

  日本育種学会第131回講演会, Jul. 2017, Japanese, 日本育種学会, 名古屋大学, Domestic conference

  Poster presentation


• インディカ型栽培イネIR36の非脱粒性を支配する新規遺伝子座の探索

  辻村 雄紀, 井上 千鶴, Than Myint Htun, 西村 彬則, 杉山 昇平, 岡 佑美, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第131回講演会, Jul. 2017, Japanese, 日本育種学会, 名古屋大学, Domestic conference

  Poster presentation


• 野生イネ（Oryza rufipogon）の遺伝的背景で芒を短くするためには - イネの栽培化における無芒性の検証にむけて –

  池本 麻衣, 大塚 光晴, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第131回講演会, Mar. 2017, Japanese, 日本育種学会, 名古屋大学, Domestic conference

  Oral presentation


• 栽培イネと野生イネの戻し交雑系統群を用いたイネの花器官を支配する遺伝子座の同定

  ISHIKAWA RYO, 渡部 貴史, 西岡 諒, Pham Thien Thanh, ISHII TAKASHIGE

  日本育種学会第131回講演会, Mar. 2017, Japanese, 日本育種学会, 名古屋大学, Domestic conference

  Poster presentation


• シロイヌナズナのリン酸濃度応答遺伝子の探索

  鈴木 太郎, 大西 美輪, 菅野 里美, 手塚あゆみ, 出口 亜由美, 永野 惇, ISHIKAWA RYO, 石崎 公庸, 深城 英弘, 三村 徹郎

  第58回日本植物生理学会年会, Mar. 2017, Japanese, 日本植物生理学会, 鹿児島大学, Domestic conference

  Oral presentation


• インディカ型栽培イネIR36の非脱粒性を支配する新規遺伝子座の探索

  辻村 雄紀, 井上 千鶴, Than Myint Htun, 西村 彬則, 杉山 昇平, 岡 佑美, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第131回講演会, Mar. 2017, Japanese, 日本育種学会, 名古屋大学, Domestic conference

  Poster presentation


• 野生イネOryza rufipogon由来の穂の開帳性に関する遺伝子座と関連遺伝子の発現について

  西岡 諒, 三日月 裕美, 田中 裕, 沼口 孝司, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Poster presentation


• 野生イネOryza rufipogonと栽培イネO. sativaの戻し交雑自殖系統を用いた節からの出芽能力の評価

  池本 麻衣, 大八木 徹弥, Pham Thien Thanh, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Poster presentation


• 野生イネOryza rufipogonとインディカ型栽培イネ（カサラス）の戻し交雑集団を用いた種子脱粒性に関する新規遺伝子座の探索

  岡 佑美, 竹中 祥尭, 高間 菜摘, 井上 千鶴, Than Myint Htun, 辻村 雄紀, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Oral presentation


• シロイヌナズナのリン酸濃度応答遺伝子の探索

  鈴木 太郎, 大西 美輪, 菅野 里美, 郷 達明, 豊倉 浩一, 永野 惇, 手塚 あゆみ, ISHIKAWA RYO, 石崎 公庸, 深城 英弘, 三村 徹郎

  日本植物学会第80回大会, Sep. 2016, Japanese, 日本植物学会, 沖縄コンベンションセンター, Domestic conference

  Poster presentation


• ジャポニカ型栽培イネ（日本晴）の非脱粒性に関与した遺伝子座の推定

  辻村 雄紀, Than Myint Htun, 沼口 孝司, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Poster presentation


• オーストラリアの野生イネOryza meridionalisを用いた種子亜鉛濃度に関わる遺伝子座の同定とその効果の検証

  谷古 健太, 岩田 将英, 門田 剛太郎, Orn Chhourn, 吉田 周作, 石井 尊生, 馬, 建鋒, ISHIKAWA RYO

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Oral presentation


• ウメ遺伝資源における黒星病およびかいよう病抵抗性の評価

  沼口 孝司, 北村 祐人, 土田 靖久, 仲 慶晃, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Poster presentation


• Oryza rufipogonとインディカ型栽培イネ（カサラス）の戻し交雑集団を用いた種子脱粒性に関する新規遺伝子座の探索

  岡 佑美, 竹中 祥尭, 高間 菜摘, 井上 千鶴, Than Myint Htun, 辻村 雄紀, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第130回講演会, Sep. 2016, Japanese, 日本育種学会, 鳥取大学, Domestic conference

  Oral presentation


• Evaluation of seed-shattering behaviour in early rice domestication

  Ryo Ishikawa, Yumi Oka, Yuki Tsujimura, Natsumi Takama, Chizuru Inoue, Than Myint Htun, Takashige Ishii

  8th World Archaeology Congress, Sep. 2016, English, Doshisha University, International conference

  [Invited]

  Invited oral presentation


• A closed panicle played an important role in rice domestication

  Ryo Nishioka, Koji Numaguchi, Pham Thien Thanh, Ryo Ishikawa, Takashige Ishii

  8th World Archaeology Congress, Sep. 2016, English, Doshisha University, International conference

  Poster presentation


• 野生イネOryza rufipogon由来の穂の開帳性を支配する遺伝子座の推定と効果の検証

  西岡 諒, 三日月 裕美, 田中 裕, 沼口 孝司, ISHIKAWA RYO, ISHII TAKASHIGE

  イネ遺伝学・分子生物学ワークショップ, Jul. 2016, Japanese, 名古屋大学, Domestic conference

  Poster presentation


• インディカ型栽培イネ（カサラス）の非脱粒性を支配するsh4座以外の遺伝子座の探索

  岡 佑美, 竹中 祥尭, 高間 菜摘, 井上 千鶴, 辻村 雄紀, Than Myint Htun, ISHII TAKASHIGE, ISHIKAWA RYO

  イネ遺伝学・分子生物学ワークショップ, Jul. 2016, Japanese, 名古屋大学, Domestic conference

  Poster presentation


• Identification of quantitative trait loci controlling seed-shattering behaviour in rice

  Yuki Tsujimura, Than Myint Htun, Chizuru Inoue, Takashige Ishii, Ryo Ishikawa

  PAG Asia 2016, Jun. 2016, English, Grand Copthorne Waterfront Hotel, International conference

  Poster presentation


• Allelic interaction at awing loci in the genetic backgrounds of wild and cultivated rice

  Mai Ikemoto, Mitsuharu Otsuka, Pham Thien Thanh, Ryo Ishikawa, Takashige Ishii

  PAG Asia 2016, Jun. 2016, English, Grand Copthorne Waterfront Hotel, International conference

  Poster presentation


• 野生イネと栽培イネの間で検出されたアルミニウムストレス耐性を支配する遺伝子座qAl1の遺伝学的解析

  和田 もりえ, 岩田 将英, 横正 健剛, 吉田 周作, Pham Tien Thanh, ISHII TAKASHIGE, 馬 建鋒, ISHIKAWA RYO

  日本育種学会第129回講演会, Mar. 2016, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Poster presentation


• 野生イネおよび栽培イネの遺伝的背景における芒の長さを支配する遺伝子座の対立遺伝子間の相互作用

  池本 麻衣, 大塚 光晴, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第129回講演会, Mar. 2016, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Poster presentation


• 野生イネOryza rufipogonと栽培イネO. sativaの戻し交雑集団を用いた穂の開帳性に関するQTL解析

  西岡 諒, 三日月 裕美, 田中 裕, 沼口 孝司, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第129回講演会, Mar. 2016, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Poster presentation


• オーストラリア由来の野生イネOryza meridionalisを用いた種子亜鉛濃度に関わる遺伝子座の同定

  岩田 将英, 谷古 健太, 門田 剛太郎, Orn Chhourn, 吉田 周作, ISHII TAKASHIGE, 馬 建鋒, ISHIKAWA RYO

  日本育種学会第129回講演会, Mar. 2016, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Poster presentation


• インディカ型栽培イネKasalathの脱粒性喪失に関与した新規遺伝子座の探索

  岡 佑美, 井上 千鶴, Than Myint Htun, 竹中 祥尭, 辻村 雄紀, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第129回講演会, Mar. 2016, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Poster presentation


• 野生イネ(Oryza rufipogon) の遺伝的背景における種子脱粒性と穂の開帳性の関係

  井上 千鶴, Than Myint Htun, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第128回講演会, Sep. 2015, Japanese, 日本育種学会, 新潟大学, Domestic conference

  Poster presentation


• Evaluation of the domestication-related traits in rice

  Ryo Ishikawa, Yumi Oka, Ryo Nishioka, Mai Ikemoto, Than Myint Htun, Chizuru Inoue, Koji Numaguchi, Takashige Ishii

  Early rice cultivation systems and their impact on social evolution and the environment., Sep. 2015, English, University College London, International conference

  [Invited]

  Invited oral presentation


• Evaluation of genetic variation among wild and cultivated rice in Cambodia

  Orn Chhourn, Rieko Shishido, Masahiro Akimoto, Ryo Ishikawa, Than Myint Htun, Ryo Nishioka, Men Sarom, Sakhan Sophany, Ouk Makara, Takashige. Ishii

  日本育種学会第128回講演会, Sep. 2015, English, 日本育種学会, 新潟大学, Domestic conference

  Poster presentation


• 野生イネOryza rufipogon由来の穂の開帳性を支配する遺伝子座の推定

  西岡 諒, 三日月 裕美, Than Myint Htun, ISHIKAWA RYO, ISHII TAKASHIGE

  近畿作物・育種研究会 第179回例会, May 2015, Japanese, 近畿作物・育種研究会, 奈良県立橿原考古学研究所, Domestic conference

  Oral presentation


• 野生イネOryza rufipogonと栽培イネO. sativaの戻し交雑自殖系統を用いた節からの出芽・出根能力およびひこばえの発生能力の評価

  池本 麻衣, 大八木 徹弥, Pham Thien Thanh, ISHIKAWA RYO, ISHII TAKASHIGE

  近畿作物・育種研究会 第179回例会, May 2015, Japanese, 近畿作物・育種研究会, 奈良県立橿原考古学研究所, Domestic conference

  Oral presentation


• 野生イネと栽培イネのアルミニウムストレス耐性を支配する遺伝子座の同定とその効果

  和田 もりえ, 岩田 将英, 吉田 周作, Pham Thien Thanh, ISHII TAKASHIGE, 馬 建鋒, ISHIKAWA RYO

  日本育種学会第127回講演会, Mar. 2015, Japanese, 日本育種学会, 玉川大学, Domestic conference

  Poster presentation


• インディカ型栽培イネ(Oryza sativa cv. IR36)における種子脱粒性の喪失に関与した遺伝子座数の推定

  西村 彬則, Than Myint Htun, 井上 千鶴, 岡 佑美, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第127回講演会, Mar. 2015, Japanese, 日本育種学会, 玉川大学, Domestic conference

  Poster presentation


• Evaluation of genetic variation among wild rice populations in Cambodia

  Orn Chhourn, Rieko Shishido, Hiroki Kageyama, Masahiro Akimoto, Ryo Ishikawa, Makara Ouk, Sarom Men, Takashige Ishii

  日本育種学会第127回講演会, Mar. 2015, English, 日本育種学会, 玉川大学, Domestic conference

  Poster presentation


• Seed shattering behaviour and abscission layer formation in rice

  Cizuru Inoue, Than Myint Htun, Yumi Oka, Kanako Inoue, Ken-ichi Ikeda, Takashige Ishii, Ryo Ishikawa

  Marchantia Workshop 2014, Dec. 2014, English, Centennial Hall, Kobe University, International conference

  Poster presentation


• 野生イネ(Oryza rufipogon)の遺伝的背景における種子脱粒性遺伝子座の相互作用と離層形態

  井上 千鶴, Than Myint Htun, INOUE KANAKO, IKEDA KENICHI, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第126回講演会, Sep. 2014, Japanese, 日本育種学会, 南九州大学, Domestic conference

  Poster presentation


• 野生イネと栽培イネのアルミニウムストレス耐性を支配する遺伝子座の同定

  和田 もりえ, 岩田 将英, 吉田 周作, Pham Thien Thanh, ISHII TAKASHIGE, 馬 建鋒, ISHIKAWA RYO

  イネ遺伝学・分子生物学ワークショップ2014, Jul. 2014, Japanese, 東京大学, Domestic conference

  Public symposium


• 野生イネ(Oryza rufipogon)における種子脱粒性遺伝子座間の相互作用

  井上 千鶴, Than Myint Htun, Orn Chhourn, 岡 佑美, ISHII TAKASHIGE, ISHIKAWA RYO

  イネ遺伝学・分子生物学ワークショップ2014, Jul. 2014, Japanese, 東京大学, Domestic conference

  Public symposium


• 野生イネ(Oryza rufipogon)の遺伝的背景における種子脱粒性遺伝子座間の相互作用

  井上 千鶴, Than Myint Htun, ISHII TAKASHIGE, ISHIKAWA RYO

  日本育種学会第125回講演会, Mar. 2014, Japanese, 日本育種学会, 東北大学, Domestic conference

  Oral presentation


• 野生イネ(Oryza rufipogon)の遺伝的背景における栽培化関連形質の評価

  西村 彬則, 岩崎 友哉, 山本 知佳, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第125回講演会, Mar. 2014, Japanese, 日本育種学会, 東北大学, Domestic conference

  Oral presentation


• Identification of a quantitative trait locus involved in abscission layer formation for seed shattering in Asian wild rice, Oryza rufipogon

  Than Myint Htun, Chizuru Inoue, Orn Chhourn, Takashige Ishii, Ryo Ishikawa

  日本育種学会第125回講演会, Mar. 2014, English, 日本育種学会, 東北大学, Domestic conference

  Oral presentation


• Evaluation of genetic diversity among rice varieties in Cambodia

  Orn Chhourn, Ryo Ishikawa, Sakhan Sophany, Ouk Makara, Takashige Ishii

  7th International Conference of Rice Genetics, Nov. 2013, English, Dusit Thai Hotel Manila, Philippine, International conference

  Poster presentation


• Closed panicles in rice domestication

  ISHII TAKASHIGE, Numaguchi K, Miura K, Yoshida K, Thanh PT, Htun TM, YAMASAKI MASANORI, Matsumoto T, Terauchi R, ISHIKAWA RYO, Ashikari M

  International Rice Genetics Symposium, Nov. 2013, English, Manila, Philippines, International conference

  Oral presentation


• A closed panicle trait regulated by OsLG1 in domesticated rice, Oryza sativa L.

  Ryo Ishikawa, Kotaro Miura, Kentaro Yoshida, Koji Numaguchi, Than Myint Htun, Pham Thien Thanh, Takashi Matsumoto, Masanori Yamasaki, Ryohei Terauchi, Motoyuki Ashikari, Takashige Ishii

  7th International Rice Genetics Symposium, Nov. 2013, English, Dusit Thai Hotel Manila, Philippine, International conference

  Poster presentation


• A closed panicle trait regulated by OsLG1 in domesticated rice, Oryza sativa L.

  Ryo Ishikawa, Kotaro Miura, Kentaro Yoshida, Koji Numaguchi, Than Myint Htun, Pham Thien Thanh, Takashi Matsumoto, Masanori Yamasaki, Ryohei Terauchi, Motoyuki Ashikari, Takashige Ishii

  7th International Conference of Rice Genetics, Nov. 2013, English, Dusit Thai Hotel Manila, Philippine, International conference

  Poster presentation


• 穂が閉じることによって野生イネはどう変化したか？

  沼口 孝司, Htun Than Myint, Thanh Pham Thien, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第124回講演会, Oct. 2013, Japanese, 日本育種学会, 鹿児島大学, Domestic conference

  Oral presentation


• イネの胚、胚乳サイズ比率に関わるEMBRYOLESS1遺伝子の解析

  堀島 佑月, 琴 梨世, ISHIKAWA RYO, 桧原 健一郎, 伊藤 純一, 長戸 康郎

  日本育種学会第124回講演会, Oct. 2013, Japanese, 日本育種学会, 鹿児島大学, Domestic conference

  Oral presentation


• Wild QTLs analysis for agronomic traits using recombinant inbred lines between Oryza rufipogon and O. sativa

  Pham Thien Thanh, Phuong Dang, Thai Phan, ISHIKAWA RYO, 石井 尊生

  日本育種学会第124回講演会, Oct. 2013, English, 日本育種学会, 鹿児島大学, Domestic conference

  Poster presentation


• 野生イネの遺伝的背景における栽培イネの非脱粒性遺伝子の効果

  ISHIKAWA RYO, Than Myint Htun, YAMASAKI MASANORI, Pham Thien Thanh, ISHII TAKASHIGE

  第52回日本植物生理学会年会, Mar. 2011, Japanese, 日本植物生理学会, 東北大学, Domestic conference

  Oral presentation


• 野生イネ (Oryza rufipogon)の種子有芒性の評価および遺伝子マッピング

  大塚 光晴, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第119回講演会, Mar. 2011, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Oral presentation


• 栽培イネ Oryza sativa Nipponbareを野生イネO. rufipogon W630で戻し交雑した自殖系統群を用いた植物と種子の形態形質に関するQTL解析

  山本 知佳, 岩崎 友哉, ISHIKAWA RYO, ISHII TAKASHIGE

  日本育種学会第119回講演会, Mar. 2011, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Oral presentation


• フィトクロムによるHd1を介したフロリゲン遺伝子Hd3aの転写制御と日長認識機構

  ISHIKAWA RYO, 青木 麻由美, 黒谷 賢一, 横井 修司, 篠村 知子, 高野 誠, 島本 功

  日本育種学会第119回講演会, Mar. 2011, Japanese, 日本育種学会, 横浜市立大学, Domestic conference

  Oral presentation


• イネ無胚乳変異原因遺伝子ENL1はSNF2ヘリカーゼ様タンパク質をコードする

  加藤 大和, 原 睦美, 佐藤 豊, 北野 英己, 長戸 康郎, ISHIKAWA RYO, 木下 哲, 武田 真, 服部 束穂

  第52回日本植物生理学会年会, Mar. 2011, Japanese, 日本植物生理学会, 東北大学, Domestic conference

  Oral presentation


• イネ属種間交雑における胚乳発生異常とOsMADS87インプリント遺伝子の制御異常

  大西 孝幸, ISHIKAWA RYO, 木下 由紀, 永口 貢, 倉田 のり, 木下 哲

  第33回日本分子生物学会年会・第83回日本生化学会大会合同大会, Dec. 2010, Japanese, 日本分子生物学会, 神戸ポートアイランド, Domestic conference

  Public symposium


• イネSNF2 ヘリカーゼ様タンパク質をコードするENDOSPERMLESS1（ENL1）の欠損は胚乳核の分裂異常を示す

  原 睦美, 加藤 大和, 佐藤 豊, 北野 英己, 長戸 康郎, ISHIKAWA RYO, 木下 哲, 武田 真, 服部 束穂

  第33回日本分子生物学会年会・第83回日本生化学会大会合同大会, Dec. 2010, Japanese, 日本分子生物学会, 神戸ポートアイランド, Domestic conference

  Poster presentation


• 野生イネと私：野生種を用いた新たな発見とその育種利用に向けて

  ISHIKAWA RYO

  日本育種学会第118回講演会, Sep. 2010, Japanese, 日本育種学会, 秋田県立大学, Domestic conference

  Invited oral presentation


• 高等植物胚乳における種の障壁成立のルールとメカニズム

  木下 哲, 大西 孝幸, ISHIKAWA RYO, 木下 由紀, 永口 貢, 倉田のり

  日本遺伝学会第82回大会, Sep. 2010, Japanese, 日本遺伝学会, 札幌市, Domestic conference

  Public symposium


• イネのbiotoron breeding system; 年6度の戻し交配を可能にする栽培法

  大西 孝幸, ISHIKAWA RYO, 山川 博幹, 木下 哲

  日本育種学会第118回講演会, Sep. 2010, Japanese, 日本育種学会, 秋田県立大学, Domestic conference

  Oral presentation


• QTL analysis for spikelet opening time using backcross inbred lines between Oryza sativa Nipponbare and O. rufipogon

  Pham Thien Thanh, Phan Dang, Thai Phuong, Ryo Ishikawa, Takashige Ishii

  日本育種学会第117回講演会, Mar. 2010, English, 日本育種学会, 京都大学, Domestic conference

  Oral presentation


• Estimation of outcrossing rate of Asian wild rice, Oryza rufipogon, under field condition

  Phan Dang Thai Phuong, Hiroki Kageyama, Ryo Ishikawa, Takashige Ishii

  日本育種学会第117回講演会, Mar. 2010, English, 日本育種学会, 京都大学, Domestic conference

  Oral presentation


• QTL analysis for useful agronomic characters using backcross inbred lines between Oryza rufipogon and O. sativa Japonica Nipponbare

  Pham Thien Thanh, Ryo Ishikawa, Naoki Mori, Takashige Ishii

  6th International Conference of Rice Genetics, Nov. 2009, English, Manila Hotel, Philippine, International conference

  Poster presentation


• QTL analysis for useful agronomic characters using backcross inbred lines between Oryza rufipogon and O. sativa Japonica Nipponbare

  Thanh PT, ISHIKAWA RYO, MORI NAOKI, ISHII TAKASHIGE

  International Rice Genetics Symposium, Nov. 2009, English, Manila, Philippines, International conference

  Poster presentation


• Genomic imprinting and reproductive barrier observed in the hybrid endosperm of rice

  Ryo Ishikawa, Mitsugu Eiguchi, Yuki Shinzaki, Nori Kurata, Tetsu Kinoshita

  6th International Conference of Rice Genetics, Nov. 2009, English, Manila Hotel, Philippine, International conference

  Poster presentation


• Abnormal development observed in the hybrid endosperm between cultivated and wild rice

  Ryo Ishikawa, Mitsugu Eiguchi, Yuki Shinzaki, Nori Kurata, Tetsu Kinoshita

  6th International Conference of Rice Genetics, Nov. 2009, English, Manila Hotel, Philippine, International conference

  Poster presentation


• 栽培イネと野生イネの種間交雑にみられる胚乳発生異常の原因

  ISHIKAWA RYO, 永口 貢, 新崎 由紀, 倉田 のり, 木下 哲

  第50回日本植物生理学会年会, Mar. 2009, Japanese, 日本植物生理学会, 名古屋大学, Domestic conference

  Oral presentation


• ゲノムインプリンティングを介した生殖隔離

  ISHIKAWA RYO, 木下哲

  第40回種生物学シンポジウム, Dec. 2008, Japanese, 種生物学会, 守谷市 デュープレックスセミナーホテル, Domestic conference

  Invited oral presentation


• Genomic imprinting and reproductive barrier observed in the hybrid endosperm of rice

  Ryo Ishikawa, Mitsugu Eiguchi, Nori Kurata, Tetsu Kinoshita

  EMBO World Workshop Genomic Imprinting, Sep. 2008, English, Temasek LifeSciences Laboratory, Singapore, International conference

  Poster presentation


• イネの胚乳における生殖隔離機構とゲノムインプリンティング

  ISHIKAWA RYO, 永口 貢, 池田 陽子, 倉田 のり, 木下 哲

  第49回日本植物生理学会年会, Mar. 2008, Japanese, 日本植物生理学会, 北海道札幌コンベンションセンター, Domestic conference

  Oral presentation


• イネの開花におけるフィトクロムの役割

  ISHIKAWA RYO, 青木 麻由美, 黒谷 賢一, 清水 久代, 横井 修司, 稲垣 言要, 篠村 知子, 高野 誠, 島本 功

  第48回日本植物生理学会年会, Mar. 2007, Japanese, 日本植物生理学会, 愛媛大学, Domestic conference

  Oral presentation


• Hd1過剰発現植物を用いたイネ開花経路の解析

  青木 麻由美, 黒谷 賢一, ISHIKAWA RYO, 横井 修司, 島本 功

  第29回日本分子生物学会, Dec. 2006, Japanese, 日本分子生物学会, 京都, Domestic conference

  Poster presentation


• イネの開花におけるフィトクロムの作用

  ISHIKAWA RYO, 篠村 知子, 高野 誠, 島本 功

  日本育種学会第110回講演会, Sep. 2006, Japanese, 日本育種学会, 愛媛大学, Domestic conference

  Oral presentation


• Natural variation in flowering time genes and night-break effects in rice

  Yasuyuki Takahashi, Ryo Ishikawa, Shuji Yokoi, Ko Shimamoto

  8th International Congress on Plant Molecular Biology, Aug. 2006, English, Adelaide, South Australia, International conference

  Poster presentation


• Natural variation in flowering time genes and night-break effects in rice

  Yasuyuki Takahashi, Ryo Ishikawa, Shuji Yokoi, Ko Shimamoto

  20th IUPMB International Congress of Biochemistry and Molecular Biology, Jun. 2006, English, Kyoto, Japan, International conference

  Poster presentation


• Hd1 overexpression delays flowering in rice under SD conditions

  Mayumi Aoki, Ken-ichi Kurotani, Ryo Ishikawa, Shuji Yokoi, Ko Shimamoto

  20th IUPMB International Congress of Biochemistry and Molecular Biology, Jun. 2006, English, Kyoto, Japan, International conference

  Poster presentation


• Effects of light quality on night-break in rice flowering

  Ryo Ishikawa, Tomoko Shinomura, Takanari Tanabata, Hisayo Shimizu, Noritoshi Inagaki, Makoto Takano, Ko Shimamoto

  20th IUPMB International Congress of Biochemistry and Molecular Biology, Jun. 2006, English, Kyoto, Japan, International conference

  Poster presentation


• Effects of light quality on night-break in rice flowering

  Ryo Ishikawa, Shojiro Tamaki, Yasuyuki Takahashi, Toru Ishizuka, Shuji Yokoi, Noritoshi Inagaki, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  International Plant Photobiology Meeting, Apr. 2006, English, Paris, France, International conference

  Poster presentation


• イネの光中断おける光質とフィトクロムの役割

  ISHIKAWA RYO, 篠村 知子, 七夕 高也, 清水 久代, 稲垣 言要, 高野 誠, 島本 功

  第47回日本植物生理学会年会, Mar. 2006, Japanese, 日本植物生理学会, 筑波大学, Domestic conference

  Poster presentation


• イネコアコレクションを用いた開花関連遺伝子の多様性の解明

  高橋 靖幸, ISHIKAWA RYO, 横井 修司, 島本 功

  第47回日本植物生理学会年会, Mar. 2006, Japanese, 日本植物生理学会, 筑波大学, Domestic conference

  Poster presentation


• Molecular basis of night break effect on rice flowering

  Ryo Ishikawa, Shojiro Tamaki, Yasuyuki Takahashi, Toru Ishizuka, Shuji Yokoi, Noritoshi Inagaki, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  5th International Rice Genetics Symposium, Nov. 2005, English, Manila, Philippines, International conference

  Poster presentation


• イネの開花における光中断の分子遺伝学的解析

  ISHIKAWA RYO, 玉置 祥二郎, 高橋 靖幸, 石塚 徹, 横井 修司, 稲垣 言要, 篠村 知子, 高野 誠, 島本 功

  第77回日本遺伝学会年会, Sep. 2005, Japanese, 日本遺伝学会, 国立オリンピック記念青少年総合センター, Domestic conference

  [Invited]

  Invited oral presentation


• Molecular basis of night break effect on flowering in rice

  Ryo Ishikawa, Takahashi Yasuyuki, Toru Ishizuka, Shuji Yokoi, Noritoshi Inagaki, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  日本育種学会第107,108回講演会, Aug. 2005, English, 日本育種学会, 筑波大学, Domestic conference

  Poster presentation


• Molecular basis of night break effect on flowering in rice

  Ryo Ishikawa, Yasuyuki Takahashi, Toru Ishizuka, Shuji Yokoi, Noritoshi Inagaki, Tomoko Shinomura, Makoto Takano, Ko Shimamoto

  10th International Congress of SABRAO, Aug. 2005, English, Tsukuba International Congress Centre, International conference

  Poster presentation


• 野生イネ由来の種子脱粒性、穂の開帳性、種子色を支配する遺伝子のマッピング

  ISHII TAKASHIGE, 崎山 弘樹, ISHIKAWA RYO, KAMIJIMA OSAMU

  近畿作物育種研究会, Jul. 2005, Japanese, 近畿作物育種研究会, 神戸大学, Domestic conference

  Oral presentation


• イネにおける光中断効果は開花促進因子Hd3aの発現抑制による

  ISHIKAWA RYO, 玉置 祥二郎, 高橋 靖幸, 石塚 徹, 横井 修司, 稲垣 言要, 篠村 知子, 高野 誠, 島本 功

  イネ・ナズナ合同ワークショップ, Jul. 2005, Japanese, 奈良県文化会館, Domestic conference

  Oral presentation


• 分子遺伝学的な方法論での探索—短日植物イネでの研究例

  島本 功, 玉置 祥二郎, 小宮 怜奈, 松尾 祥一, ISHIKAWA RYO, 池田 美香, 阿部 誠, 黒谷 賢一, 横井 修司

  第46回日本植物生理学会年会, Mar. 2005, Japanese, 日本植物生理学会, 新潟朱鷺メッセ, Domestic conference

  [Invited]

  Nominated symposium


• イネの光中断おけるフィトクロムの役割

  ISHIKAWA RYO, 高橋 靖幸, 石塚 徹, 横井 修司, 稲垣 言要, 篠村 知子, 高野 誠, 島本 功

  第46回日本植物生理学会年会, Mar. 2005, Japanese, 日本植物生理学会, 新潟朱鷺メッセ, Domestic conference

  Oral presentation


• イネにおける開花制御の遺伝子ネットワーク

  島本 功, 玉置 祥二郎, ISHIKAWA RYO, 阿部 誠, 小宮 怜奈, 池田 美香, 松尾 祥一, 黒谷 賢一, 横井 修司

  公開シンポジウム「植物の生殖研究-その最前線と今後の方向」, Nov. 2004, Japanese, 東京大学, Domestic conference

  Public discourse


• Molecular basis of night break effect on flowering in rice

  Ryo Ishikawa, Shuji Yokoi, Ko Shimamoto

  World Rice Research Conference, Nov. 2004, English, Epochal Tsukuba, Tsukuba, Japan, International conference

  Poster presentation


• 栽培イネ(Oryza sativa Nipponbare)の遺伝背景における野生イネ(Oryza rufipogon)由来の脱粒性遺伝子の作用について

  二村 直人, ISHIKAWA RYO, KAMIJIMA OSAMU, ISHII TAKASHIGE

  日本育種学会第106回講演会, Sep. 2004, Japanese, 日本育種学会, 三重大学, Domestic conference

  Oral presentation


• イネの開花を制御する遺伝子ネットワーク

  島本 功, 玉置 祥二郎, ISHIKAWA RYO, 阿部 誠, 小宮 怜奈, 池田 美香, 松尾 祥一, 黒谷 賢一, 横井 修司

  第76回日本遺伝学会年会, Sep. 2004, Japanese, 日本遺伝学会, 大阪大学コンベンションセンター, Domestic conference

  [Invited]

  Nominated symposium


• Molecular basis of night break effect on flowering in rice

  Ryo Ishikawa, Shojiro Tamaki, Shuji Yokoi, Ko Shimamoto

  58th Yamada Conference on Light Sensing and Signal Transduction in Plant Photomorphogenesis, Jun. 2004, English, Okazaki Conference Center, Okazaki, Japan, International conference

  Poster presentation


• 植物はいかに日長に応じて花を咲かせるのか？

  島本 功, 玉置 祥二郎, ISHIKAWA RYO, 阿部 誠, 小宮 怜奈, 池田 美香, 松尾 祥一, 黒谷 賢一, 横井 修司

  日本分子生物学会（奈良春大会）, May 2004, Japanese, 日本分子生物学会, 奈良県, Domestic conference

  [Invited]

  Nominated symposium


• 光中断を利用したイネの開花誘導における遺伝子発現の解析

  ISHIKAWA RYO, 横井 修司, 島本 功

  日本分子生物学会（奈良春大会）, May 2004, Japanese, 日本分子生物学会, 奈良県, Domestic conference

  Poster presentation


• Molecular basis of night break effect on flowering in rice

  Ryo Ishikawa, Shuji Yokoi, Ko Shimamoto

  Crop Functional Genomics, Apr. 2004, English, Ramada Plaza Hotel, Jeju Island, Korea, International conference

  Poster presentation


• 光中断を利用したイネの開花誘導における遺伝子発現の解析

  ISHIKAWA RYO, 横井 修司, 島本 功

  第45回日本植物生理学会年会, Mar. 2004, Japanese, 日本植物生理学会, 東京都立大学, Domestic conference

  Oral presentation


• イネの日長による開花制御の分子機構 Ⅱ、光中断の効果とその分子機構

  ISHIKAWA RYO, 横井 修司, 島本 功

  日本育種学会第105回講演会, Mar. 2004, Japanese, 日本育種学会, 東京大学, Domestic conference

  Oral presentation


• 野生イネOryza rufipogon由来の脱粒性遺伝子のマッピング

  二村 直人, ISHIKAWA RYO, KAMIJIMA OSAMU, ISHII TAKASHIGE

  日本育種学会第104回講演会, Sep. 2003, Japanese, 日本育種学会, 神戸大学, Domestic conference

  Oral presentation


• 植物の開花における短日・長日性はどうして決められるか

  島本 功, 玉置 祥二郎, ISHIKAWA RYO, 阿部 誠, 池上 顕子, 横井 修司

  日本発生生物学会第36回大会, Jun. 2003, Japanese, 日本発生生物学会, 札幌コンベンションセンター, Domestic conference

  [Invited]

  Nominated symposium


• Hd3a, an ortholog of FT, is a target of night break in the photoperiodic control of flowering in rice

  Ryo Ishikawa, Shuji Yokoi, Ko Shimamoto

  7th International Congress of Plant Molecular Biology, Barcelona, Spain, Jun. 2003, English, International conference

  Poster presentation


• イネの短日性を決定する遺伝子ネットワーク

  島本 功, ISHIKAWA RYO, 阿部 誠, 玉置 祥二郎, 早間 良輔, 井澤 毅, 横井 修司

  第44回日本植物生理学会年会, Mar. 2003, Japanese, 日本植物生理学会, 近畿大学, Domestic conference

  [Invited]

  Nominated symposium


• イネ野生種（Oryza rufipogon）由来の脱粒性遺伝子のマッピング

  ISHIKAWA RYO, KAMIJIMA OSAMU, ISHII TAKASHIGE

  日本育種学会第101回講演会, Mar. 2002, Japanese, 日本育種学会, 玉川大学, Domestic conference

  Oral presentation

• 日本育種学会

• 野生種遺伝資源を活用した熱帯アジアにおけるイネの生産性の向上

  石川 亮, 藤田 大輔, 山形 悦透, 國吉 大地, 岡田 脩平

  日本学術振興会, 科学研究費助成事業, 国際共同研究加速基金(海外連携研究), 神戸大学, 09 Sep. 2024 - 31 Mar. 2029


• Study on Anthropogenic Environmental Formation by Prehistoric Humans (Flora)

  那須 浩郎, 内藤 健, 菅 裕, 石川 亮, 大田 竜也

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Transformative Research Areas (A), Okayama University of Science, 01 Apr. 2023 - 31 Mar. 2028

  本年度は、以下の項目を中心に研究を実施した。 1. ウルシ：本年度は、中国湖北省のサンプルを中心とした現生ウルシの全ゲノム解析を行った。加えて、京都周辺のウルシを自然の山林からサンプリングし、これも全ゲノム解析を行った。さらに、ウルシの古代DNA分析を進めるための基礎研究として、現在の生漆にDNAが含まれているかどうかを検証した。 2．アズキ：本年度は、現生アズキと野生種ヤブツルアズキのゲノム解析を実施した。その結果、日本列島の栽培アズキが野生種ヤブツルアズキに最も近縁であり、アズキが日本列島起源の栽培植物である可能性が極めて高いことが示された。また、縄文時代の遺跡から出土したアズキ亜属の炭化種子のサイズ変化と種皮厚の変化を調べた結果、縄文時代から弥生時代までのアズキ亜属の種皮厚は、野生種ヤブツルアズキの変異内に収まっており、種皮厚の形質変化は起きていないことが明らかになった。 3．イネ：本年度は、イネの種子脱粒性の喪失に関わる原因遺伝子の特定を進めた。その結果、イネの種子脱粒性を制御する遺伝子は少なくとも3つ（sh4，qsh1，qsh3）あり、穂の開帳性を制御する遺伝子１つ（SPR3）との組み合わせにより、脱粒性が喪失されることが明らかとなった。突帯文期から弥生時代のイネにこれらの変異があるかどうかを古代DNAと形態（脱粒痕）の双方から検討することが今後の課題となった。古代DNA分析については、鳥取県青谷上寺地遺跡において、弥生時代の堆積物から未炭化のイネの籾殻を多数採取した。これについてイネの古代DNA抽出に成功しており、すでに5.2xのゲノム配列の決定を行なっている。


• 栽培イネが獲得した種子の非脱粒性の遺伝基盤解明と育種への活用

  石川 亮

  日本学術振興会, 科学研究費助成事業, 基盤研究(B), 神戸大学, 28 Feb. 2024 - 31 Mar. 2027

  イネは栽培化過程において種子脱粒性が抑制され収量が向上した。日本・世界各地で栽培 されるイネの種子脱粒程度には品種間差異が見られ、量的形質であることが知られているが、その遺伝基盤の全体像は解明されていない。本課題では、これまでに同定された複数の新規脱粒性遺伝子座の原因変異を同定し、それらの役割と作用を解明する。そして、各遺伝子座の変異を 識別するDNAマーカーを開発することで、脱粒性程度の改変を通じて育種に貢献するシステムを構築することを目標に研究を進めた。 本年度はジャポニカ栽培イネ日本晴の種子の非脱粒性に関わるqCSS3遺伝子座の候補領域について、組換え系統を用いた連鎖解析によって２つのDNAマーカーに限定された約500kbの領域が同定された。また、インディカ栽培イネIR36の種子の非脱粒性に関与するqCSS2とqCSS7の作用について、電子顕微鏡を用いて評価する実験系の構築に着手した。さらにAUSタイプの栽培イネカサラスの非脱粒性に関わる３つの遺伝子座について、それぞれの効果を遺伝学的に検証し、種子脱粒程度に関与することを確認した。陸稲在来品種を用いた新たな種子の非脱粒性を支配する遺伝子座の推定も進み、ジャポニカ栽培イネ日本晴と同様にqCSS3遺伝子座に加え、新規の遺伝子座が関与している可能性が得られた。これら候補領域に連鎖するDNAマーカーが設定できたが、候補領域がまだ広範に及ぶことからさらなる連鎖解析によって、脱粒性形質と密接に連鎖するDNAマーカーを開発する必要がある。


• 栽培イネが獲得した種子の非脱粒性の遺伝基盤解明と育種への活用

  石川 亮

  日本学術振興会, 科学研究費助成事業 基盤研究(B), 基盤研究(B), 神戸大学, 01 Apr. 2023 - 31 Mar. 2027


• Towards the utilization of genetic resources in the original countries by using local rice varieties collected more than half-century ago

  石井 尊生, 齊藤 大樹, 佐藤 豊, 石川 亮

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Kobe University, 01 Apr. 2022 - 31 Mar. 2026

  本研究では、半世紀以上前にインドシナ諸国で収集され、種子が国立遺伝学研究所で保存されていたイネ在来品種を研究対象とする。そして、当時インドシナ諸国の伝統的稲作を支えていた在来品種の実態を明らかにするとともに、原産国での遺伝資源としての復活を目指している。 本年度は、昨年度に引き続き、国立遺伝学研究所から分譲可能であった271品種の種子増殖を行った。うち、231品種については石垣島にて10個体ずつ生育させ、到穂日数の調査を行った。また、基本的な農業形質についても調査を行った。 インドシナ諸国（カンボジア、ベトナム、ラオス、タイ）を広くカバーする主要162品種については、いもち病の7つの標準菌株を用いて、抵抗性の程度を調査した。その結果、21品種が全菌株に、65品種が6菌株に対して抵抗性を示し、ほぼ半数の在来品種が広域抵抗性を持つことが示唆された。さらに、6つの組織（葉鞘の基部、葉の襟、葉耳、葉舌、柱頭、穎の先端）におけるアントシアニンの色素沈着についても調査を行ったところ、41品種が紫色の組織を持っていた。一番多かったのは葉鞘の基部と穎の先端での着色でそれぞれ39品種見られたが、葉舌の着色は稀で5品種しか観察されなかった。 集団構造解析については、162品種から抽出したDNAを鋳型として、12個のマイクロサテライトマーカー用いた多型調査を試みた。パスポートデータに関しては、種子分譲を受けた全277品種についての精査を終えた。


• 半世紀以上眠るイネ在来品種遺伝資源の凱旋復活に向けて

  石井 尊生, 齊藤 大樹, 佐藤 豊, 石川 亮

  日本学術振興会, 科学研究費助成事業 基盤研究(B), 基盤研究(B), 神戸大学, 01 Apr. 2022 - 31 Mar. 2026


• Searching for genetic loci derived from salt-tolerant rice, which contribute to circumventing toxicity of Na+ and Cl-

  堀江 智明, 石川 亮

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C), Grant-in-Aid for Scientific Research (C), Shinshu University, 01 Apr. 2022 - 31 Mar. 2025

  R4年度に、耐塩性イネ在来種ノナボクラと塩感受性の栽培種コシヒカリの交雑系統（染色体断片置換系統群：CSSLs）を利用して、塩ストレス下（25-75 mM: 計9日間）においてClの地下部の蓄積が、ノナボクラ様に有意に高まる系統を発見していた（SL504系統）。この選抜系統の栄養成長期での、より詳細な部位別のClとNaの含量調査を実施した所、塩ストレス下においては、最新未熟葉や完全展開新葉で、有意にClとNa双方ともに高蓄積することが示された。 プレリミナリーな観察として、SL504系統を土耕栽培して、生殖成長期に長期の塩ストレス処理を施した所、コシヒカリよりも耐塩性が強い傾向を示されていた。そこで、R5年度は、再度SL504系統を土耕栽培して同様の試験を行った。SＬ504系統は、対照であるコシヒカリに比べて地上部の視覚的ダメージがより低減しており、穂の乾燥重量を指標とした比較においては、コシヒカリよりも重い傾向を示した。R6年夏には、試料の数を増やし、生殖成長期における収量を含んだ耐性評価のいくつかの指標を詳細に定量評価する予定である。 この系統に関しては、共同研究者との協力により、コシヒカリとの戻し交雑後代集団BC1F1を作製した。BC1F2系統の種子の採取が予定より遅れてしまったが、R6年秋にそれが達成され、早ければR6年末ころからの表現型解析に使用できる状態になる。これらの材料を用いて、栄養成長期、生殖成長期でのClやNa蓄積や収量などの重要な指標を解析し、これらの表現型をもたらす責任遺伝子の絞り込みを進めて行く。


• アフリカのイネジーンプールに潜在する有用遺伝子の計画的利用に向けた種間雑種戦略

  小出 陽平, 山形 悦透, 石川 亮, 藤田 大輔

  日本学術振興会, 科学研究費助成事業, 基盤研究(B), 北海道大学, 01 Apr. 2021 - 31 Mar. 2025

  将来の食糧安定生産のため、利用可能な遺伝子プールを拡大することは、育種学の使命の一つである。アフリカ栽培・野生イネは、膨大な遺伝変異を有するが、有用遺伝子探索がほとんど行われていない未利用遺伝資源である。本研究では、ゲノム情報を利用した効率的な遺伝子探索システムをアフリカイネに適用し、初期生育や耐虫性などの有用形質に関わる遺伝子の迅速な単離を行う。また、雑種不稔性を回避する種間橋渡し系統を確立し、異種遺伝子の利用を促進するとともに、未解明である種間雑種強勢の遺伝基盤を明らかにし、種間雑種の新しい活用法を構築する。 これまでに、主に、独自のアフリカ栽培イネ集団をもちいたゲノム解析を行い、データを参照配列である日本晴にマッピングした際に得られるSNP情報に基づくゲノムワイド関連解析実験系を構築した。この実験系を用いることで様々な形質に関してゲノムワイド関連解析を行うことが可能となった。さらに、SNP情報より、アフリカ栽培イネを複数の分集団に区分し、各分集団ごとの系統の特徴化を進めた。また、アフリカ栽培イネが持つ遺伝子の単離を迅速に行うために、分集団ごとに系統を選抜し、これら系統の交配による組換え自殖系統群作出を行った。当該年度においては、F3世代まで世代促進を進めた。さらに、アフリカイネが持つ初期生育性や耐虫性など、特徴的な表現型の予備的解析を行った。その結果、初期生育の旺盛さに関与すると考えられる第2葉と第3葉の葉身長にアフリカ栽培イネ内で表現型多型があることが示された。ゲノムワイド関連解析を行ったところ、第2葉葉身長および第3葉葉身長と有意に関連のある染色体領域が明らかとなった。また、複数の種間雑種不稔遺伝子について、遺伝子同定に向けた準備を行うとともに、ゲノム編集による遺伝子ノックアウトの実験系の構築を進めた。


• アフリカのイネジーンプールに潜在する有用遺伝子の計画的利用に向けた種間雑種戦略

  小出 陽平, 山形 悦透, 石川 亮, 藤田 大輔

  日本学術振興会, 科学研究費助成事業 基盤研究(B), 基盤研究(B), 北海道大学, 01 Apr. 2021 - 31 Mar. 2025


• 栽培イネに秘められた雑草魂とは？

  石川 亮

  日本学術振興会, 科学研究費助成事業 挑戦的研究(萌芽), 挑戦的研究(萌芽), 神戸大学, 09 Jul. 2021 - 31 Mar. 2024


• 二国間交流「植物分子遺伝学と植物考古学の相互評価によるイネ栽培化過程の検証」

  日本学術振興会, 国際交流事業, Nov. 2021 - Oct. 2023, Principal investigator


• 野生イネの形態に学ぶ持続的病害抵抗性の再構築と活用

  石川 亮, 林 敬子, 黒木 信一郎

  日本学術振興会, 科学研究費助成事業 基盤研究(B), 基盤研究(B), 神戸大学, 18 Jul. 2018 - 31 Mar. 2022


• Identification of the responsible genes that govern Na and Cl accumulation in leaves of rice under salinity stress

  Horie Tomoaki

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Shinshu University, 01 Apr. 2018 - 31 Mar. 2021

  We searched for genetic loci that govern leaf Na accumulation in rice under salt stress using backcross recombinant inbred lines derived from cultivated rice and wild rice (composed of 159 lines). A quantitative trait locus for Na accumulation was deduced to exist in Chromosome 1 and 5, respectively. However, the responsible genes have not yet been isolated. On the other hand, chromosome segment substitution lines (CSSLs) derived from cultivated rice and salt tolerant rice (composed of 44 lines) were used to search for important loci controlling Cl accumulation in rice under salt stress. Several unexpected problems have hindered the progression of research for Cl. Trial and error has, however, led to the assumption that root Cl accumulation could be an important index to consider salt tolerance of rice. Based on the root-based anion analysis using CSSLs, at least one genetic locus that significantly influences on the level of root Cl accumulation was identified.


• Detection of novel loci involved in reduced seed-shattering behaviour in cultivated rice and their application for increasing yield

  Ryo Ishikawa

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Kobe University, Apr. 2018 - Mar. 2021, Principal investigator

  During rice domestication, seed-shattering behaviour was supressed, but the loci involved in shattering loss were not fully identified. The objective of this study was to genetically identify novel loci involved in non-seed shattering behaviour of cultivated rice, Oryza sativa, using wild rice O. rufipogon.. We identified qCSS3 (QTL for the Control of Seed Shattering in rice on chromosome 3) using japonica rice Nipponbare and qCSS2/qCSS7 using indica rice IR36. In addition, three novel loci were also identified using AUS type cultivated rice Kasalath.

  Competitive research funding


• Property of rice blast resistances gene with a moderately resistant phenotype of wild rice

  Hayashi Keiko

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), National Agriculture and Food Research Organization, 01 Apr. 2017 - 31 Mar. 2020

  Rice blast is one of the most destructive rice diseases worldwide. Introducing resistance genes into cultivars is an economic strategy to protect plants from the disease. Knowing the property of resistance genes with a moderately resistant phenotype contributes to increased germplasm for disease-resistant breeding. However, such genes were visually assessed in the field, making it difficult to further analyze them. We revealed the location of the resistance gene that was derived from a donor of wild rice (Oryza rufipogon Griff.) and further revealed the resistance property of the gene. An image-based phenotyping method using cut-flower dye solution enabled the assessment of leaf and panicle blast without observer variability. The method revealed the progression of the rice blast disease, and the influence of the resistance gene on lesions formed on leaf and panicle.


• Improvement of sustainability for crop production and development of next-generation plant resource through gene circulation between relative species

  FUJITA DAIUSKE

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Saga University, 19 Jul. 2016 - 31 Mar. 2020

  In this study, there are three parts. (1) The whole genome sequence of 150 accessions of African rice (Oryza glaberrima) that is maintained in genetic resource center of International Rice Research Institute had been conducted through next-generation sequencer. A lot of SNPs are detected through whole genome sequence data. (2) The biotic stress and yield related traits on 150 accessions of African rice were characterized. The multiple gene loci for these characteristics were detected by Genome-wide association study based on SNP information. (3) To develop next generation plant resource, BC1F1 seeds from multiple cross combinations between indica rice line with mitigating sterility and African rice were developed.


• Evaluation of the process of rice domestication based on loss of seed shattering(Fostering Joint International Research)

  Ishikawa Ryo

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Fund for the Promotion of Joint International Research (Fostering Joint International Research), Kobe University, 2015 - 2019, Principal investigator

  Asian cultivated rice, Oryza sativa is known to be domesticated from its wild form O. rufipogon. A loss of seed shattering is one of the most obvious phenotypic changes selected for during rice domestication. The process and chronology of rice domestication are not known very well, because the present rice plant materials are not capable for evaluation of these questions. In this study, the novel loci involved in a loss of seed shattering have been identified and their roles on rice domestication has been discussed by views of plant genetics and plant archaeology.

  Competitive research funding


• Identification of genetic loci in relation to salt tolerance of rice using wild rice and development of breeding basis toward the production of resistant cultivars

  Horie Tomoaki

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Shinshu University, 01 Apr. 2015 - 31 Mar. 2018

  Phenotypic evaluation for the sensitivity to salt stress has led to the findings that Oryza rufipogon, which is an ancestral wild rice to the cultivated rice (Oryza sativa), showed higher salt sensitivity with significantly higher Na accumulation in leaves compared with a japonica rice cultivar Nipponbare under salt stress. We have analyzed concentrations of key elements, Na, K, Ca and Mg, in leaves under salt stress using backcross recombinant inbred lines (BRILs), produced by crossing Nipponbare (recurrent) with wild rice (donor). Based on the data of leaf Na accumulation from 152 lines, three important candidates regions for QTL were identified. In addition, genetic regions, which could include QTL for the control of the accumulation of K, Ca, or Mg, were also narrowed down.


• Clarification of genes related to key traits in the early stage of rice domestication

  Ishii Takashige, ISHIKAWA Ryo

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Kobe University, 01 Apr. 2014 - 31 Mar. 2018

  A closed panicle is one of the key traits in the early stage of rice domestication. This trait is considered to lead significant reduction in seed shedding and outcrossing rate. Here, we first fine-mapped chromosomal regions responsible for the panicle shape, i.e., OsLG1 regulatory region and minor locus on chromosome 5. Seed awning and floral morphology are co-related to the seed shedding and pollination behavior, respectively. Genetic controls of these traits were also investigated. The above results confirmed that many loci of these traits were involved in rice domestication.


• Clarification of gene flow between wild and cultivated rice in tropical Asian countries

  ISHII TAKASHIGE, Nguyen Thi Lang, Phuong Dang Thai Phan, Ouk Makara, Tin Htut, Than Myint Htun

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), Kobe University, Apr. 2014 - Mar. 2017

  In order to figure out the nature of Asian wild rice, Oryza rufipogon, natural wild populations were investigated in three tropical Asian countries, Vietnam, Cambodia and Myanmar. Based on the genetic variation among wild populations using molecular markers, genetic population structures of annual and perennial wild rice were found to vary according to the propagation manners and environmental conditions. Gene flow between wild and cultivated rice was detected using molecular markers on domestication traits. It suggests that frequency of the gene flow is mainly due to the plant distribution conditions.

  Competitive research funding


• Evaluation of rice domestication by loss of seed shattering

  Ishikawa Ryo, IKEDA KEN-ICHI

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Kobe University, Apr. 2014 - Mar. 2017, Principal investigator

  Loss of seed shattering was one of the key phenotypic changes selected for in the domestication of many crop species. Asian cultivated rice, Oryza sativa L., was domesticated from its wild ancestor, O. rufipogon, and three seed-shattering loci, qSH1, sh4 and qSH3, have been reported to be involved in the loss of seed shattering in cultivated rice. In this study, we analysed the seed-shattering behaviour of wild rice using introgression lines carrying the cultivated alleles from O. sativa Nipponbare in the genetic background of wild rice, O. rufipogon W630. We found that the interaction of mutations at these two loci may have played a role in the initial loss of seed shattering during rice domestication.

  Competitive research funding


• 二国間交流「植物分子遺伝学と植物考古学の相互評価によるイネ栽培化過程の検証」

  石川 亮

  日本学術振興会, 二国間交流事業（オープンパートナーシップ共同研究）, Nov. 2014 - Oct. 2016, Principal investigator

  Competitive research funding


• Toward the understanding of the regulation of seed shattering habit in cereal plants using wild species

  ISHIKAWA RYO, TAKASHIGE Ishii

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Kobe University, 2011 - 2013, Principal investigator

  Previously, two major quantitative trait loci (QTLs, qSH1 and sh4) were shown to be responsible for the seed-shattering degree. We produced introgression lines carrying cultivated alleles from O. sativa Nipponbare at the two major QTLs in wild rice O. rufipogon W630, genetic background. The introgression lines carrying Nipponbare alleles at either or both loci showed complete or partial abscission layer formation, respectively. This result indicated that other unknown loci might be involved in enhancing seed shattering in wild rice. Using an F2 population between Nipponbare and the wild introgression line carrying the Nipponbare alleles at the two QTLs. We identified a single QTL regulating seed-shattering degree and named it qSH3. A significant effect on seed-shattering degree was observed for the wild introgression line carrying Nipponbare alleles at qSH3 and the two QTLs, suggesting an important role of qSH3 on seed shattering in coordination with the two QTLs.

  Competitive research funding


• Analysis of OsMADS87 in the control of cellularization and reproductive barrier in the endosperm obtained from rice interspecific crosses

  ISHIKAWA Ryo

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Young Scientists (B), Kobe University, 2009 - 2010, Principal investigator

  Endosperm often exhibits developmental defects when interspecific or interploidy crosses are conducted. Analysis of transcriptome using RNA from hybrid endosperm identified deregulation of rice homologs of Arabidopsis PHERES1 gene family. In the detailed analysis of OsMADS87 expression, it was found that OsMADS87 expression levels were correlated with the timing of cellularization. These results suggest that possible involvement of regulatory systems of PHERES1 gene family in post-zygotic barrier of early endosperm development. Analysis of transgenic plants with overexpression or RNAi constructs were also carried out, however, not significant effect was observed in their endosperm development. It might be possible that several OsMADS87 family genes are also involved in the control of early endosperm development.

  Competitive research funding

• なぜ縄文に農業始まらず？

  Other than myself, 日本経済新聞, 02 Feb. 2025, 科学で迫る 日本人

  Paper


• 三つの変異で種が落ちなくなりイネの栽培が始まった！

  朝日新聞出版, AERA with Kids 学習BOOKシリーズ, 21 Jul. 2023, ニュースとマンガで今、一番知りたい！ 日本の歴史

  Paper


• イネ種子脱粒性の喪失

  NHK, ヒューマニエンス ４０億年のたくらみ, “植物” 支配者は周りを動かす

  Media report