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Volume 83 (2014)
- Issue 4 Pages 299-
- Issue 3 Pages 195-
- Issue 2 Pages 105-
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Volume 83, Issue 4
Displaying 1-14 of 14 articles from this issue
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Review
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Ken Ishimaru, Kazuhiro Ujiie2014 Volume 83 Issue 4 Pages 299-304
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSGrain size is the main factor determining rice yield. Recently, several genes controlling grain size have been cloned leading to have achieved the new aspect about the mechanism determining grain size. Among them, loss of function of 4 genes enlarged grain size and these results suggested the existence of a kind of limiting system that determines grain size. Functional analysis of 5 genes elucidated that the spikelet hull size might mainly explain the natural variation in grain size. In this article, we reviewed the new aspect about regulation of rice grain size.View full abstractDownload PDF (1069K)
Regular Paper
Agronomy
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Takeo Sakaigaichi, Takayoshi Terauchi, Taiichiro Hattori, Shoko Ishika ...2014 Volume 83 Issue 4 Pages 305-313
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSThe growth and nutrient uptake of forage sugarcane plants were examined under multi-ratooning cultivation using various K2O application levels to develop a management system considering the mineral balance in the plant. Compared with the usual management (control), the plant in the plots with reduced K2O application levels had a lower K/(Ca+Mg) ratio (index of mineral balance) and a significant difference was observed from the 2nd ratoon. This was because the K concentration decreased and the Ca and Mg concentrations increased due to reduction of K2O application level. Therefore, the K/(Ca+Mg) ratio can be improved by continuous K2O fertilizer reduction. On the other hand, soil exchangeable K contents were lowered by reduced K2O application and the yield was decreased significantly in multi-ratooning cultivation. Therefore, continuous K2O fertilizer reduction management is not recommended and the usual amount of K2O fertilizer should be maintained. Since the soil exchangeable K contents decreased even in the control plot, additional K2O fertilizer such as manure should be applied in order to maintain the yield level in multi-ratooning crops. The usual amount of N application was considered appropriate and that of P2O5 application superfluous. Since the soil exchangeable Ca and Mg contents were reduced in multi-ratooning crops, Ca and Mg application to the soil should be conducted using lime.View full abstractDownload PDF (1230K) -
Aki Uchiyama, Tsukasa Tanizaki, Masamichi Nakatsukasa, Yoshiya Akasi2014 Volume 83 Issue 4 Pages 314-319
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSChicken droppings are commonly applied prior to wheat sowing in autumn in the wheat-paddy rice double cropping system. It is used as organic fertilizer instead of customary chemical fertilizer. We investigated the effects of the chicken droppings on yields of wheat and rice and on the contents of nitrogen, phosphoric acid and potassium in soil. Wheat yields with chicken dropping was higher than with no chicken droppings: The spike numbers, kernels per spike and thousand kernels weight were all higher with chicken droppings. However, the wheat yield was lower with chicken droppings than with customary chemical fertilizer. Rice yields with chicken droppings was not different from that without chicken droppings but was lower than with customary chemical fertilizer. After wheat harvest, the nitrogen content of soil before and after succeeding rice cultivation was nearly the same in the fields with and without chicken droppings. On the other hand, phosphoric acid and potassium contents of soil were lower after rice cultivation than before rice cultivation. Chicken dropping were effective as nitrogen fertilizer for wheat immediately after spraying but not for succeeding rice in the wheat-paddy rice double cropping system. On the other hand, chicken droppings were effective as phosphoric acid and potassium fertilizer for both wheat and rice cultivation.View full abstractDownload PDF (763K)
Genetic Resources and Evaluation
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Tadashi Takahashi, Natsumi Kaneoka, Eiichirou Kamada, Sayaka Uchida, T ...2014 Volume 83 Issue 4 Pages 320-325
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSWheat cultivar “Haruyutaka” bred in Hokkaido and “Daichinominori” bred in Kyushu and their F1 hybrid were grown in Yamaguchi, and the kernel weight at different positions on the spikes was investigated. Haruyutaka had lighter kernels than Daichinominori at all positions throughout four successive seasons. All kernels in the first, second and third florets of Haruyutaka were lighter than those of Daichinominori, and the third floret kernel was particularly lighter than the first and second floret kernels in Haruyutaka. Daichinominori had heavy kernels even in the third floret in Yamaguchi. F2 kernel weight was as heavy as those of Daichinominori and heavier than those of Haruyutaka. Among the F2 kernels the third floret kernel was lighter than the first and second floret kernels, while its standard deviation on the third floret was larger than those of the first and second floret kernels. There would not be genetic segregation in F2 kernel weight in the first and second florets.View full abstractDownload PDF (780K) -
Satoshi Aoyama, Hisanori Shimada2014 Volume 83 Issue 4 Pages 326-332
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSThe breeding of azuki bean tolerant to damage by cool shading is indispensable for stable production of azuki bean in Hokkaido. However, it was difficult to evaluate cool tolerance of extremely late-flowering genetic resources because of the need to control flowering. We established a method for evaluating the cool tolerance in flowering and pod setting damage. Firstly, we examined the cool tolerance of Buchi-syoryu No.1, which is the most cool tolerant among the existing resources, and 97 genetic resources. The flowering stages were made uniform by short-day treatment. The number of flowers and pods setting were counted from day 6 to 10 after the 7-day cool shading treatment (high/low, 15/10°C, 50％ shading) from the flowering stage. We evaluated the cool tolerance by the number of flowers and pod setting rate as compared with Buchi-shoryu No.1 which is considered “medium”, and found that 4 resources including Acc2265 are tolerant and 22 resources are moderately tolerant. Secondly, the effect of cool shading treatment for 7 and 10 days was compared. In either treatment, Acc2265 surpassed Buchi-syoryu No.1 in the number of flowers, and pod setting rate. Ten-day treatment was more definite than 7-day treatment. Hence, we propose a method to select the cool-tolerant resources based on the number of flowers from day 5 to 9 after the 10-day treatment, and then based on the number of pods setting from day 10 to 13 after the treatment, for evaluation of many materials.View full abstractDownload PDF (1738K)
Crop Physiolory and Cell Biology
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a Comparison with the Oryza sativa Japonica Cultivar, NipponbareNorimitsu Hamaoka, Osamu Ueno2014 Volume 83 Issue 4 Pages 333-340
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSThe optimization of nitrogen (N) application level and the development of cultivars with high physiological N use efficiency (NUE) are needed to establish a sustainable rice cropping system. In our previous study, we found that a strain of wild rice species Oryza nivara (IRGC105715; NVR) shows high NUE under low N conditions. In this study we investigated photosynthetic traits of NVR in comparison with the O. sativa japonica cultivar Nipponbare. Plants were water-cultured under three N conditions; standard N (1N), medium N (1/2N) and low N (1/4N) levels. At the vegetative stage, leaves of NVR showed a higher photosynthetic rate, stomatal conductance (Gs) and CO2 fixation activity than those of Nipponbare under 1/2N and 1/4N conditions. NVR also showed higher maximum quantum yield of photosystem II than Nipponbare under 1/4N condition. NVR tended to have higher specific leaf weight and leaf N content than Nipponbare. Under 1/2N and 1/4N conditions, NVR exhibited higher photosynthetic N use efficiency (PNUE) than Nipponbare. These data demonstrate that NVR have higher photosynthetic capacity and PNUE than Nipponbare under low N conditions. These traits may be attributed to the maintenance of higher Gs, photochemical activity and leaf N content under a low N condition in NVR. It is suggested that the photosynthetic properties of NVR may be a promising genetic trait for breeding of cultivars suitable for low N-input agriculture.View full abstractDownload PDF (981K)
Modelling, Information and Environment
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Hiroyuki Shimono2014 Volume 83 Issue 4 Pages 341-351
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSThe present study compared the current food production capacity of 14 major crops in Japan, and also estimated the potential ability for producing food for calories in all paddy fields and upland fields. The production of the 14 crops per capita per day on a calorie basis in Japan was 2497 kcal in 1961 and decreased to 795 kcal in 2010. This level was 26% of the world average, and 37% of the African average. Under the condition where all fields were used for 3 high yielding crops (rice, potato and sweetpotato) to increase the productivity, the production is estimated to increase toward 1626 kcal, but this is still 76% of the African average. Four scenarios were tested, i.e.,; agricultural land area will decrease and yield will not increase (scenario 1), agricultural land area will be kept at the present level but yield will not increase (scenario 2), agricultural land area will be kept at the present level and yield will increase (scenario 3), and the other conditions are the same as within scenario 1 but the population will not decrease (scenario 4). In 2030, the production was estimated to be 1608 kcal in scenario 1, 1826 kcal in scenario 2, 1926 kcal in scenario 3 and 1464 kcal in scenario 4. The present study suggested that agricultural land area needs to be maintained the current level at least, and the productivity per land area need to be improved for increasing food security.View full abstractDownload PDF (1737K)
Research and Technical Note
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Hiromichi Yamaguchi, Mami Ishizaki, Tetsuya Ishikawa, Hiroshi Kato, Hi ...2014 Volume 83 Issue 4 Pages 352-355
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESS -
Takeo Sakaigaichi, Yoshifumi Terajima, Takayoshi Terauchi, Makoto Mats ...2014 Volume 83 Issue 4 Pages 356-361
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSThe recommended harvest cycle is two harvests per year in forage sugarcane cultivation. Here, the validity of three harvests per year was studied using forage sugarcane variety KRFo93-1. Two harvests per year plot (1st and 2nd crops) as control and three harvests per year plot (1st, 2nd and 3rd crops) were established. Annual dry matter yields of the two harvests per year plot in the 1st and 2nd years were 3.38 and 5.69 kg m-2, respectively, and those of three harvests per year were 1.90 and 3.12 kg m-2, respectively. Thus, in both years, the annual dry matter yields were significantly higher in two harvests per year than in three harvests per year. The productivity in the 3rd crops in the three harvests per year plot was lower because its growth duration coincided with the low temperature season. In the 2nd year, the ratoon starting date of the 1st crop in the two harvests per year plot was the same as that of the 1st crop in the three harvests per year plot, but the stem length of the former was significantly longer than that of the latter. This means that ratoon growth was more vigorous in the two harvests per year system and it is concluded that the conventional cultivation cycle of two harvests per year is appropriate for forage sugarcane.View full abstractDownload PDF (1030K) -
Masami Furuhata, Makoto Tanoi, Katsura Tomita, Asako Kobayashi, Masahi ...2014 Volume 83 Issue 4 Pages 362-367
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSSeedling emergence following direct seeding in a flooded paddy field at a low temperature was measured. Germination characteristics under aerobic conditions and coleoptile elongation under anaerobic conditions associated with seedling emergence were assessed. The rice cultivars used were 21 high eating quality rice cultivars from Hokkaido, Tohoku, and Hokuriku districts, and Etsunan 242, which has high eating quality and good seedling emergence. The speed of seedling emergence was positively correlated with the final seedling emergence rate. The speed of germination and the germination coefficient were not correlated with the speed of seedling emergence, suggesting that germination characteristics were not related to seedling emergence. The speed of coleoptile elongation, speed of seedling emergence, and final seedling establishment rate were higher in Etsunan 242 than in other rice cultivars with high eating quality. The speed of seedling emergence, final seedling emergence rate, final seedling establishment rate, and dry weight of above-ground plant parts were highest in the cultivars from Hokkaido followed by Tohoku and Hokuriku in this order.View full abstractDownload PDF (1150K) -
Jun Ushiki, Stoshi Hayashi, Tsuji Hiroyuki2014 Volume 83 Issue 4 Pages 368-373
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSEffect of top-dressing of nitrogen fertilizer on the yield and ear number of rice (Oryza sativa) “Hoshimaru”, a representative variety for dry direct seeding in Hokkaido, was examined. Experiments were conducted in the paddy fields (soil type: Andosol) in Sapporo, Hokkaido from 2010 to 2012. Nitrogen fertilizer was top-dressed once a week from the 1.5-2.0 leaf stage to panicle formation stage of rice. Field water was drained to spray a herbicide at the 6.0 leaf stage of rice, i.e., 5.0-6.0 leaf stage of barnyard grass (Echinochloa crus-galli) in 2010 and 2012. Top-dressing of nitrogen fertilizer at the 5.0 leaf stage, 1-2 days before water drainage, had little effect on hulled grain yield or ear number of rice. In the same fields, top-dressing of nitrogen fertilizer at the panicle formation stage most effectively increased hulled grain yield and ear number of rice than that at the other stages. On the other hand, in the field with flooded water maintained, top-dressing of nitrogen fertilizer at the 6.5-7.5 leaf stage of rice, 1 week before the panicle formation stage, increased the grain yield and ear number of rice more effectively than at other stages.View full abstractDownload PDF (1633K) -
Hidekazu Kobayashi, Masahiro Chiba, Kenji Nagata2014 Volume 83 Issue 4 Pages 374-379
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSSpikelet number per unit area (spikelet number) is an important factor for high rice yields. Spikelet number reportedly has a positive correlation with nitrogen accumulation in the shoots at the heading stage, but the coverage of the correlation is unclear. In the present study, we examined the relationship between nitrogen accumulation and spikelet number in the high-yield cultivars ‘Hokuriku 193’ and ‘Mizuhochikara’ under the condition of high nitrogen application. Nitrogen accumulation in rice shoots at the heading stage increased with an increase in the amount of applied nitrogen, but the spikelet number did not increase significantly when the amount of applied nitrogen was increased from 24.5 to 33.5 g m-2. Analysis of the relationship between nitrogen accumulation in rice shoots at the heading stage and spikelet number by using the linear-plateau model revealed that the nitrogen accumulation required to achieve maximum spikelet number was 22.0 and 20.0 g m-2, and that the maximum spikelet number was 54680 and 58951 spikelets m-2 in ‘Hokuriku 193’ and ‘Mizuhochikara’, respectively.View full abstractDownload PDF (834K)
Information
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Emi Kameoka2014 Volume 83 Issue 4 Pages 380-381
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSI participated in the IRRI Young Scientists’ Conference (IYSC) held at the International Rice Research Institute (IRRI) from 14–18 October 2013. The purpose of the IYSC was to provide young scholars/researchers with a chance to present the findings of their research to scientists in the global rice society. This was the second IYSC and held together with the Global Rice Science Partnership (GRiSP) Asia Forum 2013. Not only IRRI scientists, but also NARES (national agricultural research and extension systems) partners in Asia and scientists from other CGIAR centers, attended; thus, there was a diverse audience, having participants from the fields of genetic diversity, better varieties, crop and environment, value adding, targeting and policy, and last-mile delivery. I presented a paper entitled, “Contribution of root system development and hydraulic conductivity to shoot biomass under drought stress conditions in rice” in the session of the genetic diversity. I obtained a lot of new knowledge and ideas from many fruitful comments and advice from both expert and young rice scientists at the conference. I also joined a tour of IRRI to observe the huge gene bank and center pivot. I was very much impressed with the ongoing and future researches in IRRI. Several research groups have been collaborating closely to develop tolerant varieties against multiple stresses such as drought, salinity, heat, and flooding. I learned that such collaborations are essential to connect the achievements generated from basic research with the development of practical and useful varieties. There were a few presentations that showed the benefits of Golden Rice, which has high vitamin A content. Golden Rice will be released in 2016 in the Philippines. There were many opinions and arguments in the session, but I felt that the scientists are working on Golden Rice with a sincere attitude, taking the public into consideration. I would like to express my heartfelt thank to Dr. Ando Radanielson, one of the organizers of the IYSC for his great support. Thanks are also due to Dr. Tsutomu Ishimaru, JIRCAS seconded scientist to IRRI, for his kind advice on this report. The IYSC provided such a wonderful opportunity for young rice scientists like us and we look forward to the next one.View full abstractDownload PDF (616K) -
[in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...2014 Volume 83 Issue 4 Pages 382
Published: 2014
Released on J-STAGE: November 04, 2014
JOURNAL FREE ACCESSDownload PDF (584K)
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