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Volume 71, Issue 1
Displaying 1-17 of 17 articles from this issue
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Yasunori KODA2002 Volume 71 Issue 1 Pages 1-10
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESS -
Ken-ichi MATSUSHIMA, Kenzo WAKIMOTO, Satoshi YOSHINAGA, Kohei TASAKA, ...2002 Volume 71 Issue 1 Pages 11-16
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe application of calcium cyanamid is effective in the control of apple snail (Pomacea canaliculata (LAMARCK) ) that damage rice seedlings. An investigation of the effects of calcium cyanamide application on seedling emergence in the submerged direct seeding of rice was carried out in pot experiments. In the case of seeds not coated with calcium peroxide, seedling emergence was inhibited. On the other hand, seeds coated with calcium peroxide showed normal seedling emergence, and the emergence rate increased as the quantity of calcium cyanamid application increased. In pot experiments, the concentration of calcium cyanamid in the soil solution after puddling was measured during 4 days. Compared with the concentration of calcium cyanamid in the soil just after puddling, the concentration of calcium cyanamid in the soil 4 days later was decreased to 27% ∼17%. In the other experiment carried out, in which soil was incorporated with wheat straw, calcium cyanamid inhibited the seedling emergence of non coated seeds, but that of coated seeds was not.View full abstractDownload PDF (913K) -
Kunjo MIURA, Yoshiharu WADA, Kazuyuki WATANABE2002 Volume 71 Issue 1 Pages 17-23
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe experiments were conducted to examine the growth pattern of first-year and second-year konjak plants. Moreover, the relation between corm weight and cormlet weight was investigated in relation to the number of cormlets per plant. The leaf area of the first-year konjak plant maximized 43 days after the leaf unfolding, but specific leaf weight increased until the later growth stage. The number of cormlets did not increase after 20 days following leaf unfolding. The corm weight increased linearly after 10 days after the leaf unfolding. The number of cormlets was not different among cultivars for the first -year plants and the second-year plants. Leaf area and dry matter accumulation to organs of the second-year plants were much larger than that of the first-year plants, but the growth patterns of first-year and second-year plants were similar. The measurements of the dry weight of the corm and the number of cormlets revealed that the greater the number of cormlets per plant, the less the dry weight of the corm. This indicates the competition of dry matter accumulation between the corm and the cormlets. The removal of lateral buds at 7 days after the leaf unfolding caused a significant increase in the dry weight of the corm compared with that from the untreated konjak plant. This suggests that the dry matter accumulation in the corm can be enhanced the number of cormlets is reduced.View full abstractDownload PDF (903K) -
Kunio MIURA, Yoshiharu WADA, Kazuyuki WATANABE2002 Volume 71 Issue 1 Pages 24-27
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSExperiments were conducted to examine if the increase in the dry weight of underground organs of a Konjak plant is regulated by photosynthate production. The reduction of leaf area by removing petiolules suppressed the increase in the dry weight of underground organs of the Konjak plant. The rate of dry weight increase of underground organs per leaf area was nearly the same regardless of the leaf area, and it was 0.2 g dm-2 week-1. The shading treatment increased the leaf area 1.5 times at the relative light intensity of 15% and suppressed the dry weight of underground organs at the relative light intensity of 25% and below, the dry weight was maintained at the same level of a control plot at the relative light intensity more than 50%. The dry weight was increased 1.5 times in a whole plant, and underground organs were compared with a control plot by 14 hours of light irradiation ( 16 kLx, from 18 : 00 to 8 : 00) at night for 43 days. Thus dry matter accumulation in the underground organs of the Konjak plant is affected by photosynthate production.View full abstractDownload PDF (550K) -
Yoshiharu WADA, San-Iku YUN, Hiroki SASAKI, Tadanobu MAEDA, Kunio MIUR ...2002 Volume 71 Issue 1 Pages 28-35
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSJaponica-Indica hybrid rice cultivars, Suweon 287 and Suweon 290, showed a high yield under the upland cultivation conditions as well as the lowland cultivation conditions. This study was conducted to elucidate the high yielding ability of the Japonica-Indica hybrid rice cultivars under the upland cultivation conditions through examination of dry matter production and nitrogen absorption in comparison with Japonica upland and lowland cultivars, Toyahatamochi and Koshihikari. Suweon 287 and Suweon 290 had a large leaf area index and large sink capacity, determined by the grain number and grain weight, which might be caused by the increased nitrogen absorption before anthesis. These cultivars showed a higher crop growth rate after anthesis mainly due to the high mean leaf area index during the ripening period. In addition, these cultivars showed relatively high net assimilation rates even though their high mean leaf area index during the ripening period. Therefore, it may be concluded that the Japonica-Indica hybrid rice cultivars have a high yielding capacity even under upland cultivation conditions. In 1994 which had a dry growing season in August, Suweon 287 and Suweon 290 showed higher photosynthetic rates under both insufficient and sufficient soil water conditions compared to the two Japonica cultivars, suggesting the high drought-resistance ability of these cultivars.View full abstractDownload PDF (1204K) -
Shigenori MIURA, Yoshiaki WATANABE2002 Volume 71 Issue 1 Pages 36-42
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSTo evaluate the effect of living mulch, we examined the weed biomass and the growth and yield of sweet corn (Zea mays L.) cultivated with three legume living mulches without the application of herbicide and without tillage. The living mulch plants alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) were seeded in autumn. During the corn growth period in the following year, weed growth was effectively suppressed by all three living mulch plants. Both growth rate and yield of sweet corn with white clover living mulch were comparable to the conventional cultivation, but alfalfa and red clover living mulches caused the yield reduction in sweet corn. The percentage of stand was thought to have been reduced due to the competition for light and nutrients. The nitrogen absorption rate of sweet corn increased with its growth. On the other hand, the nitrogen absorption rate of living mulch plants decreased with the growth of sweet corn. These results suggest that competition between sweet corn and living mulch plants for nitrogen would be small. We concluded that white clover is the best of the three legume living mulch plants for weed control without significantly affecting sweet corn production.View full abstractDownload PDF (967K) -
Takayuki NAKANO2002 Volume 71 Issue 1 Pages 43-48
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIn this study, the progress of growth stage and change in freezing hardiness of tea [Camellia sinensis (L.) O. Kuntze] bud were examined from January to April in relation to air temperature for 10 years. The growth stage was shown by days to 70% sprouting at 25°C under 14-hour day length (DTS) . In the buds examined in January, DTS was over 15 days. DTS decreased as the time of examination was delayed and was only a few days in the buds examined in late March. The higher the average air temperature in late January, the longer the DTS in mid-February, but the higher the average air temperature after mid-February, the shorter the DTS later in the season. Freezing hardiness was shown by LT5 [lethal temperature (°C) of 50% buds] . It was the lowest in January, increased after mid-February, and reached - 5°C around a sprouting time. The average air temperature in early January showed a negative correlation with LT5 at later season, but that after late February showed a positive correlation in most cases. Thus the progress of growth stage and the decline of freezing hardiness were caused by increasing in air temperature after mid-February and late February, respectively. The LT50 of the buds at a certain growth stage varied with the year, suggesting that the freezing hardiness was also influenced by some factors other than the growth stage.View full abstractDownload PDF (946K) -
Tadanobu MAEDA2002 Volume 71 Issue 1 Pages 50-56
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSFrom 1991 to 1994, a rice cultivar, Koshihikari, was cultured under dense (25 hills/m2) and sparse (17 hills/m2) planting with a low supply of agricultural chemicals and with continuos application of farmyard manure (FM) or chemical fertilizer (CF) . Grain yield under dense planting was not different from that under sparse planting when FM was applied without CF, but was higher in the former than in the latter when FM was applied together with the small amount of CF or only a small amount of CF was applied. This is because the former had a larger number of ears than the latter. When a large amount of CF was applied, grain yield in the plot with dense planting was lower because of the fewer florets, lower percentage of ripened grains and lighter grains though having many ears. Panicle blast occurred more frequently under dense planting, especially when a large amount of CF was applied. No difference was observed in the occurrence of insects between the plots with dense and sparse planting. Grain yield under dense planting was higher than in the plot with sparse planting regardless of the weather condition when FM was applied together with a small amount of CF. However, it w as lower when a large amount of CF was applied even in a good weather year. It is concluded that dense planting sometimes gives a high yield when FM is applied continuously, but often causes over-luxuriant growth, less dry-matter production and frequent occurrence of panicle blast when CF is applied continuously. Therefore, the method for high yield must be explored with sparse planting, which also costs less and stabilizes rice production.View full abstractDownload PDF (1015K) -
Yuji MATSUE, Yosuke UCHIMURA, Hirokazu SATO2002 Volume 71 Issue 1 Pages 57-61
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSWe examined the correlation of hardening speed of “mochi” (rice cake) of glutinous rice with the gelatinization temperature, an amylographic characteristic, and air temperature during the ripening period, in six glutinous rice cultivars. The hardening speed of “mochi” showed a strong negative correlation with the gelatinization temperature in all cultivars examined. Thus, it is possible to use gelatinization temperature as an indicator of the hardening speed of “mochi”. When the gelatinization temperature was lower than 62°C, the hardening speed of “mochi” was as low as 1.0, which is not suitable for “mochi” processing. Therefore, the gelatinization temperature of 62°C was suggested to be useful as an indicator for selecting glutinous rice cultivars superior in “mochi” hardening speed. Air temperature during the ripening period showed a strong negative correlation with the hardening speed of “mochi”, and a strong positive correlation with the gelatinization temperature. When the air temperature during the ripening period was lower than 24°C the hardening speed of “mochi” was very slow. The hardening speed varied with the year more widely than with the cultivar, suggesting that the hardening speed of “mochi” is affected more largely by the air temperature during the ripening period than by genetic background.View full abstractDownload PDF (731K) -
Tsuneya AKAZAWA, Emiko SHIRAIWA, Noriko SATOH, Takeo SASAHARA2002 Volume 71 Issue 1 Pages 62-67
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSEating quality, flavor and pod color of immature soybean (Glycine max (L.) Merr.) seeds (edamame) were examined using 7 vegetable-type and 2 grain-type soybean cultivars. The edamame was sampled at the optimum harvesting period for eating. One group was boiled for 3 min and then stored at 5, 15 and 25°C for 24 h (the boiled storage group) . Another group was stored raw under the same conditions and then boiled for 3 min (raw storage group). Eating quality, flavor and pod color of the two groups of edamame were evaluated by 10 to 15 panelists. The eating quality was positively and significantly correlated with flavor of edamame in the raw storage group 〔r=0.726 (p<0.05), 0.824 (p<0.01), and 0.843 (p<0.01) at 5, 15 and 25°C, respectively〕, and in the boiled storage group, 〔r=0.939, 0.951, and 0.934 (p<0.01) stored at 5, 15 and 25°C respectively〕. However, pod color was not correlated with eating quality or flavor, except for the edamame stored after boiling at 25°C. The eating quality and flavor scores of edamame in the raw storage group was evaluated higher than those in the boiled storage group (eating quality : t=3.786, Flavor : t=3.687, p<0.001, df=51). The eating quality and flavor scores differed among vegetable-type soybeans. However, these two sensory factors were evaluated more highly in the vegetable-type soybean than in the grain-type soybeans in both storage groups (eating quality : t=2.822, p<0.001, Flavor : t=2.023, p<0.005, df= 34) . The sensory values differed between the same vegetable-type soybeans cultivated in different areas, even in a small district (Shonai).View full abstractDownload PDF (818K) -
Tomio ITANI2002 Volume 71 Issue 1 Pages 68-75
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSAromatic rice has been cultivated in many regions throughout Japan and in South and South-East Asian countries from ancient days. In an attempt to clarify the agronomic characteristics of aromatic rice collected from all over Japan, 71 randomly selected cultivars were cultivated along with 21 foreign aromatic cultivars from 7 countries and 18 Japanese non-aromatic leading cultivars. In addition, 44 Japanese aromatic cultivars and 6 old and 12 new non-aromatic cultivars were examined their leaf characters. (1) Local Japanese aromatic cultivars had larger height, fewer and larger panicles, greater straw weight, lower yield, less tolerance to lodging, and more awns than the new cultivars. (2) Morphologically, the local Japanese aromatic cultivars were divided into eastern and western groups. The former showed earlier heading, shorter culm, smaller panicle, lower yield, thinner stem, and less tolerance to lodging than the latter. (3) Foreign aromatic cultivars were similar to Japanese ones in terms of long-culm, heavy-panicle and low-yield, but they had poorer biomass and harvest index with later maturing-larger panicle. (4) Local Japanese aromatic cultivars had longer and wider flag leaf, larger flag-leaf angle, faster leaf senescence, and longer neck internode of panicle than new cultivars. The old, non-aromatic cultivars were medium of aromatic cultivars and new, non-aromatic cultivars. (5) Because aromatic cultivars possess the old agronomic characters and big variations, it is important to make ample examinations to select them for cultivation or breeding.View full abstractDownload PDF (1044K) -
Hiroyuki SHIRATSUCHI, Yoichi OHDAIRA, Jun-ichi TAKANASHI2002 Volume 71 Issue 1 Pages 76-83
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSFactors adversely affecting seedling emergence and establishment of giant-embryo cultivar ‘Haiminori' were studied and a nursery method for mechanical transplanting was developed. In ‘Haiminori', the germination rate was 96.7%, but a low seedling emergence rate (69.2%) and low establishment rate (33.0%) were sometimes recorded. This suggested that ‘Haiminori' was inferior in seedling growth after germination. The low seedling emergence rate and establishment rate were attributed to a high malformation rate (50.2%) and large amount of sugar exudation from the seeds during germination. However, threshing damage to the large embryos affected neither the seedling emergence rate nor establishment rate. Neither seedling emergence rate nor establishment rate of ‘Haiminori' were improved by changing imbibition and greening temperature, harvest time, nursery media, and sowing rate. Seedling height in chaff mats was higher than in soil. In the chaff mats, the tensile strength of the seedling mats was 0.46 N, twice as strong as 0.23 N in soil. A sufficient number of seedlings was obtained at a sowing rate of 270 g per nursery box. In conclusion, ‘Haiminori' was inferior in seedling growth after germination, which was mainly attributed to a high malformation rate and large amount of sugar exudation from the seeds. Seedling mats suitable for mechanical transplanting were obtained with the chaff mats and at a sowing rate of 270 g per nursery box.View full abstractDownload PDF (1137K) -
Teruo ARASE, Ayako SUZUKI, Junkoh MARUYAMA2002 Volume 71 Issue 1 Pages 84-90
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSGrowth and reproductive yield of Yabumame (Amphicarpaea edgeworthii Benth.), a geocarpic edible wild legume, were investigated by field experiments. In experiment 1, seedlings of subterranean seeds derived from a natural habitat were transplanted to the field at a hill space of 30 cm within a row and 45 cm interrow spacing with 3 levels of support poles. A significant difference was observed in the increasing rates in the number of main-stem leaves between the plants with and without support poles since the 30th day after germination, when spiral elongation of their main stems started. The yield of subterranean seeds was approximately 20 gm-2, but the total reproductive yield including aerial seeds was 40 g m-2 The latter had a highly positive correlation with the total number of leaves. However, the plants with over 120 leaves per m2 to produce more aerial seeds than subterranean seeds. In experiment 2, the growth of seedlings of aerial seeds (SA) was compared with that of subterranean seeds (SS). SA and SS were transplanted to a level field with 1 plant per 1 m2 During the vegetative growth, the increasing rates of main-stem leaves were SA=SS, but the specific growth rates in total number of leaves were SA<SS. The yield of subterranean seeds may be increased by the increase in total leaf number through the improvement of sowing date, planting density, and support poles. It may also be increased by concentrating the seed production on the subterranean part by the breeding technology.View full abstractDownload PDF (1179K) -
Katsunori ISOBE, Satoru MURAKAMI, Akira TATEISHI, Kazunari NOMURA, Hir ...2002 Volume 71 Issue 1 Pages 91-95
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe effects of arbuscular mycorrhizal fungus (Glomus R10) on the root morphology and physiology of kidney bean (Phaseolus vulgaris L.) have been investigated. Infection with arbuscular mycorrhizal fungi reduced the length and the number of tap roots, and the 1st and 2nd order lateral roots. However, the number of the 1st order lateral roots per unit length of tap root and that of the 2nd order lateral roots per unit length of the 1st order lateral root were not affected by the infection. Application of phosphorus fertilizer did not change the morphology of the roots. These findings suggest that infection with arbuscular mycorrhizal fungi alters the morphology of the root system of kidney bean. The infection also promoted the bleeding rate and triphenyl-tetrazoliumchioride (TTC) -reducing power per unit length of roots, but did not affect the bleeding rate per plant. It was unclear whether the increase in bleeding rate and TTC-reducing power was due to the physiological changes in the roots or whether the increase in TTC-reducing power and water absorption by the arbuscular mycorrhizal fungi. Our results show that infection with arbuscular mycorrhizal fungi affects the morphology of kidney bean root; however, the effect on the physiology of roots remains to be examined further.View full abstractDownload PDF (871K) -
Zhijian YANG, Osamu SASAKI, Tomohide SHIMOTASHIRO2002 Volume 71 Issue 1 Pages 96-101
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe effect of soil moisture at a low temperature on the growth of rice seedlings, several Indica and Japonica varieties was investigated. In this experiment, the wet soil plots (WP) (70% of water holding capacity) and flooded soil plots (FP) were set. The seedlings were kept at a normal temperature (20°C) until the third leaf blade was fully emerged and then exposed to 11°C for 12 days. After that, they were again grown at a normal temperature. After the exposure to a low temperature, the top dry weight (DW) was higher in WP than in FP, and no difference was observed between Indica and Japonica. The root DW, the number of roots, the seminal root length, the number of lateral roots and the bleeding rate were higher in WP than in FP. These tendencies were remarkable in Indica varieties. The superior growth of the seminal root and development of the lateral roots might be responsible for the superior root activities. After the seedlings returned to the normal temperature, the recovery of top DW, root DW, the root number, the bleeding rate and the rooting ability was higher in WP than in FP. Based on these results, it is considered that the higher recovery of root growth and activities of the root in WP compared to FP after returned to the normal temperature might be due to the lesser damage to root growth and activity in WP during the low temperature exposure. Thus, it is considered that the rearing of seedlings under wet soil conditions can reduce the low-temperature damage in seedlings at the nursery period in double cropping of Indica varieties in Hunan Province of China.View full abstractDownload PDF (965K) -
Satoshi MORITA, Hiroyuki SHIRATSUCHI, Jun-ichi TAKANASHI, Konosuke FUJ ...2002 Volume 71 Issue 1 Pages 102-109
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe effects of high-temperature stress on rice ripening is well documented. However, it is unclear which is more effective on rice ripening, high night temperature (HNT) or high day temperature (HDT) . In this study, the effects of HNT (22/34°C; day/night temperature) has been compared with those of HDT (34/22°C), with a control (22°C continuously or 28/20°C; max/min temperature) under growth cabinets. The average grain weight decreased under HNT compared with that of control, but it was not affected under HDT. On the other hand, the percentage of normal (undamaged) grains decreased not only under HNT, but also under HDT. Furthermore, the decreases in grain weight and grain quality took place in spite of the grain position in a panicle. The indicator of grain volume (length×width×thickness) correlated with the grain weight. Under HNT, grain width and thickness both decreased; under HDT, grain width decreased, but thickness increased. These results suggest that the decrease in grain width and its thickness affected the grain weight decreases under HNT, whereas under HDT the grain weight remains stable because the loss of width would be fully compensated for by increases in its thickness.View full abstractDownload PDF (1210K) -
Yoshihiko HIRAI, Makoto TSUDA, Atsushi ENAIDA2002 Volume 71 Issue 1 Pages 110-115
Published: March 05, 2002
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSTo clarify the effect of varietal differences in the maintenance respiration rate on dry matter production at the vegetative stage in rice, the maintenance respiration rates of the top of the plant in 26 rice varieties were investigated by the starvation method. The relationship between the dry matter increase and the dark respiration rate under natural conditions was also examined between four varieties with a low rate of maintenance respiration (Tainou 67, Esoshimamochi, Binato and Mangasa) and those with a high rate (Bouzu, Dular, Mangetsumochi and Alborio) . A varietal difference was found in the maintenance respiration rate of the top and was not related to the nitrogen content of the top. Under natural conditions, the large dark respiration in the varieties with high-maintenance rates was not due to large growth respiration, but to large maintenance respiration. The gross photosynthetic rate of the low-respiration varieties was lower than that of the high-respiration ones, although the net photosynthetic rate of the low-respiration varieties was higher than that of the high-respiration ones because of differences in the maintenance respiration rate, which corresponds to 5% of gross photosynthesis. This study showed that the starvation method was useful for the selection of rice varieties with low-maintenance respiration rates. The effect of the varietal difference of the maintenance respiration rate in the vegetative stage on dry matter production was shown quantitatively.View full abstractDownload PDF (925K)
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