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Volume 61, Issue 2
Displaying 1-19 of 19 articles from this issue
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Seiichi FUJII, Hitoshi SAKA1992 Volume 61 Issue 2 Pages 193-199
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSTo determine the effect of brassinolide (BR, 2α, 3α, 22R, 23R-tetrahydroxy-24S-methyl-B-homo-7-oxa-5α-cholestan-6-one) on the translocation of assimilate during the ripening of rice plants (Oryza sativa L. cv. Nipponbare), tracer studies of 14C were carried out with pot-cultivated rice plants under greenhouse conditions. BR was sprayed twice with foliar application at concentrations of 10-3 and 10-2 ppm (30 ml/pot), respectively, 10 days before the heading and the heading stage. Rice plants were fed with 14CO2 to make them carry out 14CO2 assimilation at the flowering stage. Both the distribution and radioactivity of 14C in each plant organ were determined by two methods using autoradiography and a liquid scintillation spectrometer. Most of the 14C presented in the leaf blades at 1 hour after assimilation. The 14C in the leaf blades rapidly decreased after 1 day and subsequently translocated into the culms and panicles. Finally, most of the 14C translocated into the panicles after 21 days. Compared with the untreated controls, BR enhanced the incorporation of the 14C into the leaf blades after 1 hour, lowered the 14C in culms, and promoted the accumulation of the 14C in the panicles from after 3 days. These results suggest that the promotive effect of BR on the ripening of rice plants is attributed to the promotion of the translocation of photosynthates.View full abstractDownload PDF (946K) -
Sakae AGARIE, Waichi AGATA, Fumitake KUBOTA, Peter B. KAUFMAN1992 Volume 61 Issue 2 Pages 200-206
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSTo investigate the combined effects of silicon application and light intensity on growth characteristics, dry matter production, photosynthetic rate, and transpiration rate, three cultivars (cv. Nipponbare, Koshihikari, Suweon 258) were water cultured, using solutions of +Si (silicon application) and -Si (no-application) under two different light conditions (no shade and shade). Silicon application promoted growth and dry matter production in the three cultivars. The greatest effect was found in a japonica-type cultivar, Koshihikari, grown under the shade condition. Silicon application prevented overtranspiration and increased water use efficiency in leaves. This was effective in curbing photosynthetic depression and chlorophyll destruction in aged leaves. The maintenance of photosynthetic activity was regarded as one of the main reasons for the dry matter production increase by silicon application.View full abstractDownload PDF (692K) -
Fumitake KUBOTA, Satoru OKANO, Waichi AGATA, Tadao C. Katayama1992 Volume 61 Issue 2 Pages 207-212
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSTo elucidate the dry matter productivity of O. glaberrima introduced from West Africa, the responses of several main growth parameters and photosynthetic rate to fertilizing levels were compared with those of O. sativa from West Africa and O. sativa c. v. Nipponbare, one of the leading Japanese cultivars. Seven strains of O. glaberrima, nine strains of O. sativa and c. v. Nipponbare were grown in the rock-wool water culture system with Kimura's B solution. The plants were grown at 75% concentration of the standard solution during the first month after germination. Thereafter the plants were grown in the solutions with three concentration levels (50, 150, and 400% of the standard) for one month, then investigated. The main results were as follows: (1) Both West African species were vigorous in growth. Average values for the two parameters, dry weight and leaf area, were considerably larger in West African species than in c. v. Nipponbare. (2) Dry weight, leaf area and the number of culms were significantly larger in O. glaberrima than in O. sativa at each level of solution concentration. Also a clear interspecific difference was found in the sensitivity of these parameters to solution concentrations. O. glaberrima, a less improved species in productivity, was highly sensitive. (3) Photosynthetic rate in single leaf was lower in O. glaberrima than in O. sativa at all the three levels of solution concentrations, while the range of variation in photosynthetic rate with concentration was larger in O. glaberrima.View full abstractDownload PDF (735K) -
Makoto TSUDA, Shinichi TAKAMI, Daiju YOKOE1992 Volume 61 Issue 2 Pages 213-217
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSRice panicles start to transpire just after heading. We can therefore expect that the water potential of panicles changes little prior to heading and varies in response to transpiration after heading. To test this hypothesis, we followed the ontogenetic change of plant water potential from the panicle initiation stage to maturity in a wetland rice cultivar, Koshihikari, grown in a submerged rice field. Diurnal changes were also studied on selected days. Leaves underwent a gradual decrease in midday water potential, which is associated with plant development. A similar trend was also found in panicles, except just before the exposure of panicles to the atomosphere when a sudden and brief increase in the panicle water potential was observed. Before heading, the water potential of panicles changed little diurnally, whereas it fluctuated markedly in concert with a change in potential evapotranspiration after heading. The water potential of panicles was consistantly higher throughout phenological development than that of leaves, except during the last stage of the grain-filling period. The results suggest that, before heading, the water potential of rice panicles appears to be coupled strongly with water flux for growth. After heading, the influence of transpiration becomes predominant. Superimposed on these is the increase in plant resistance to water transport that is associated with plant development.View full abstractDownload PDF (576K) -
Yuji MATSUE, Kumi FURUNO, Tomohiko YOSHIDA1992 Volume 61 Issue 2 Pages 218-222
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThis study was undertaken to determine the effects of shading during mid- to late-ripening stages on the palatability of cooked rice. The changes in protein content, amylose content, and amylographic characteristics effected by shading were also studied. Rice plants grown in a paddy field were shaded for 10 days by cheesecloth beginning from 15, 20, 25, and 30 days after heading time. About 70% of solar radiation was eliminated by the treatment. All of the shading treatments clearly deteriorated the palatability. The degree of the deterioration was larger in the rice shaded at earlier stages. The shading also increased protein and amylose content and decreased the maximum viscosity and breakdown values in amylographic characteristics. It was estimated that the deterioration of palatability by shading was related to the increase of protein and amylose content and changes in the gelatinization properties of the rice starch.View full abstractDownload PDF (603K) -
Susumu ARIMA, Noriyuki TANAKA, Jirou HARADA, Kazuhiro MATUMOTO, Fumita ...1992 Volume 61 Issue 2 Pages 223-228
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe yield performance of water chestnut plants cultivated in paddy fields under conditions of varying combinations of time and density of transplanting was investigated with reference to the change of number of rosettes. Yield was measured using the fresh weight of commercially valuable fruits, which weighed more than 10 g each, and was analyzed as the product of average weight per valuable fruit and their number per unit area. The latter, furthermore, was analyzed as the product of the number of productive rosettes per unit area and that of valuable fruits on a rosette. After transplanting, the number of rosettes increased to the maximum rosette number stage with the emergence of the branch stem, and after that decreased slightly, and then approached the final number of productive rosettes. By early transplanting and high density of transplanting, the increase rate of rosettes per unit area was enhanced and the maximum rosette number stage was hastened. As a result, the final number of productive rosettes per unit area increased. Yield varied from 780 gm-2 to 1140 gm-2 with treatment. High yield was obtained by early transplanting and high density of transplanting. Since the average fresh weight of valuable fruits did not vary by treatment, yield was mainly influenced by the number of valuable fruits per unit area. Judging from the small change seen in the number of valuable fruits on a rosette, the number of valuable fruits unit area varied in accordance with the number of productive rosettes per unit area. Therefore, the number of productive rosettes per unit area showed the closest correlation with yield among yield components. Consequently, the increase rate in the number of rosettes before the maximum rosette number stage was regarded as the important factor in greatly effecting yields.View full abstractDownload PDF (668K) -
Susumu ARIMA, Jirou HARADA, Noriyuki TANAKA1992 Volume 61 Issue 2 Pages 229-234
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe relationship between the canopy formation and yield performance of Trapa bispinosa Roxb. in paddy fields was investigated under the following six conditions: vinyl house culture (VH); shade culture (SC); and open field culture (OP); with and without fertilizer (F). The speed of the canopy formation varied with treatments, and the formation of the complete canopy of emersed leaves was hastened in the following order :VH+F>VH>OP+F>OP>SC+F>SC. The number of productive rosettes tended to increase corresponding to the earliness of the maximum rosette number stage. Furthermore, the variation at about 20 days was observed during the first flowering time to correspond to that during the maximum rosette number stage. Yield varied from 506 to 1190 gm-2 and increased under the condition of early canopy formation. The cumulative number of flowers per rosette ceased to increase at the same time, regardless of the timing of the first flowering, which showed a significant correlation with the timing of the first flowering. Also, high correlations were seen between the maximum rosette number stage and the first flowering, and between the cumulative number of flowers and the number of valuable fruits per rosette. Therefore, it can be proved that the increase in number of valuable fruits per rosette depends on the increase in the cumulative number of flowers per rosette owing to a prolonged flowering period, which arises from the promotion in canopy formation and commencement of flowering.View full abstractDownload PDF (693K) -
Kiyoshi TAKAHASHI1992 Volume 61 Issue 2 Pages 235-243
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe main aim of this paper is to present how the leaf sheath concerns internode elongation in rice, using the japonica cultivar Sasanishiki. Leaf sheaths were removed at the begining of the rapid elongation of the second internode, namely, the booting stage. Removal of a whole leaf sheath induced a marked growth inhibition of the first and second internodes. This inhibiting effect caused by the complete removal of the leaf sheath was just partly recovered only gibberellin A3 was applied. On the other hand, the effects of partial removal of the leaf sheaths are reversed by covering the internode itself or the whole panicle with aluminium foil or wrap film. These results suggest that the leaf sheath may act as a protective cover with regard to environmental stress in the young internodes and may help the tissue of the second internodes to retain the ability to respond to the endogenous gibberellin. The leaf sheath, especially that of the first leaf (flag leaf), may also stimulate the elongation of the first and second internodes through the enhancement of endogenous gibberellin production in the young panicles that are covered with these leaf sheaths.View full abstractDownload PDF (1034K) -
Motoko OKUNO, Kazuaki ADACHI1992 Volume 61 Issue 2 Pages 244-250
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIt is important to soak milled rice grain in water before boiling in order to achieve cooked rice of the best quality. The quantity of absorbed water may be influenced by the characteristics of milled rice. In this paper, the relationship between such properties of milled rice, as water content, raw weight, dry weight, volume, specific gravity, hardness of grain, and water absorption characteristics during the soaking process were examined for five varieties, Chidori, Koshihikari, Nihonmasari, Nipponbare, and Kinki-33, which were harvested from two different areas. Temperature effect on water absorption in the soaking process was also analyzed. 1) The water absorption rate of milled rice during The soaking process sharply decreased at temperatures below 20°C, but the final water content slightly increased. 2) Hardness was the property of the milled grain that differed most by variety. 3) Water absorption characteristics of milled grain had a highly positive correlation with grain hardness with regard to the absorption rate and the final water content. 4) Both water absorption and grain hardness were increased with milled percentage, and the regression coefficient between water absorption and grain hardness varied with milled percentage. 5) The change of grain hardness with milled percentage suggested differences of histogenesis in grain filling among the varieties. These results indicated that the water absorption characteristics of milled grain during soaking in water were based on the grain characteristic that was apparently determined by grain hardness and milled percentage.View full abstractDownload PDF (882K) -
Hiroshi HASEGAWA1992 Volume 61 Issue 2 Pages 251-256
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSNitrate uptake ability from low-concentration nitrate solution (below 1 mM) was evaluated based on Michaelis-Menten kinetics in 12 Japanese barley cultivars. Two kinetic parameters, Km and Vmax, were determined using 7-day-old seedlings that had been cultured with distilled water for 6 days and treated with induction medium (100 μM KNO3 plus 500 μM CaSO4) for 24h prior to the experiment. The uptake solution was composed of 25-1000 μM KNO3 and 500 μM CaSO4. At 25°C, Km and Vmax in the 12 cultivars used in this experiment ranged from 50.9 to 111.7 μM and from 2.24 to 4.99 μmol·g-1 f.w.·h-1, respectively. Km obtained in this experiment was roughly coincident with the values demonstrated by earlier studies in some plants including barley. A singnificantly high correlationship (r=0.896) was found between Km and Vmax. Km and Vmax decreased at low temperatures and the extent of the decrease in Km depended on the cultivars. The ratio of Km at 15°C to that at 25d°C ranged from about 1.00 to less than 0.50. Furthermore, it was observed that Vmax was not related to such morphological traits as plant fresh weight, first leaf length, and root length.View full abstractDownload PDF (736K) -
II-Doo JIN, Yoshio SANO, Jun INOUYE1992 Volume 61 Issue 2 Pages 257-263
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSHistological peculiarities of the abscission layer between pedicel and spikelet were investigated in Asian rice, African rice, their putative ancestral wild species, and the other nine wild Oryza species. As in the African rice (O. glaberrima Steud.), both the normally developed and partially developed abscission layers were found in the African rice's ancestral wild species (O. barthii). In other wild Oryza species including the putative ancestral wild species (O. rufipogon and O. nivara) of Asian rice (O. sativa L.), only the normally developed abscission layer was found. In these wild oryza species, the parenchymatous cells of the abscission layer cracked completely at maturity time, except for the wild species O. longistaminata. In the African ancestral wild species, sclerenchymatous cells were situated around the central vascular tissue, while any sclerenchyrmatous cells were situated in the other wild Oryza species. At maturity time, therefore, the thickness of the supporting zone consisting of the central vascular tissue and the sclerenchymatous cells was greater in the African ancestral wild species than in the other wild Oryza species. As the result the latter was essentially more fragile. According to its shape, the abscission layer was classified into three types : curved, straight, and sunken. All the wild rice plants belonging to the A genome species had the curved type of abscission layer.View full abstractDownload PDF (1010K) -
Shinji SHIMADA, Makie KOKUBUN, Hideaki SHIBATA, Shigeo MATSUI1992 Volume 61 Issue 2 Pages 264-270
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSWhile increasing leaf area increases CO2-fixing ability of plants, it also increases transpiration and may cause water deficit within a plant. This study was conducted in order to analyze the combined effects of leaf area and water-supply treatments on photosynthesis, water status, and yield of pot-grown soybeans (Glycine max [L.] Merr. cv. Tachinagaha). When plants reached the R4-R5 stage, the leaf area of a whole plant was altered by defoliating one, both; or none of the lateral leaflets of each trifoliate, and three levels of water-supply treatments (2100, 1000, 500 ml/day) were given until maturity. Transpiration per plant (Tr/P) was approximately equal to water supply regardless of leaf area under water-restricted conditions (1000, 500 ml/day). With sufficient water supply (2100 ml/day), Tr/P varied with leaf area. Across all the treatments, there was a clear linear relationship (r =0.994**) between apparent photosynthetic rate (AP) and stomatal conductance (gs) at one week after the initiation of water-supply treatment. Increasing water supply increased gs and AP. In water-restricted plants, decreasing leaf area by defoliation raised leaf water potential and caused higher gs and AP of the remaining leaves. Successive water stress of water-restricted plants decreased leaf chlorophyll content and AP at the late ripening stage. Grain yield was reduced by defoliation only under well-watered conditions but was not affected by defoliation in water-restricted plants. The data suggest that water supply proportionate to leaf area is essential to maximizing soybean yield.View full abstractDownload PDF (756K) -
Jiro TATSUMI, Nobuko ENDO, Yasuhiro KONO1992 Volume 61 Issue 2 Pages 271-278
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe effects of shading on growth and allocation pattern of photosynthate in the seminal root of corn seedlings were studied using 13C as a tracer. Corn seedlings, preshaded for 2 days (light intensity was reduced to 57% or 25% of nonshaded plants), were fed with <13>C-labelled CO2 for 2 h under given light conditions, then allowed to grow for the subsequent 3 days. The extension rate of the seminal axis was not affected by shading. The total number and length of laterals were reduced by shading, while a marked increase of number and length of laterals was observed in the specific region within 10 cm from the apex of shaded plants. The 13C allocation to the laterals of the seminal root was reduced by shading ; in contrast, allocation was increased in the seminal axis. The decrease of 13C allocation to the laterals was associated with the reduction of the development of laterals. The increase of 13C allocation to the seminal axis was due to a marked accumulation of 13C in the root tip and axis within 10 cm from the apex, and this accumulation was strongly associated with the enhancement of the growth of laterals and the extension of the axis that occurred in the same region.View full abstractDownload PDF (823K) -
Md. Abdul KARIM, Naoki UTSUNOMIYA, Shoji SHIGENAGA1992 Volume 61 Issue 2 Pages 279-284
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSSalt tolerance of ten cultivars of hexaploid triticale was assessed at the time of germination and at the early seedling stage in a laboratory experiment. Concentrations of the NaCl solutions employed in this experiment were 0, 50, 150, 250 and 350 mM. In none of the cultivars used in this experiment was it possible to obtain fully developed seedlings at 250 and 350 mM NaCl concentrations. Shoot growth was more sensitive to salinity than germination and root growth. It is, therefore, suggested that shoot growth is one of the most important characters for screening tests of salt tolerance in hexaploid triticale at this early stage of growth. Variation in salt tolerance among the ten cultivars was observed, with Currency, Yoreme, Welsh, and Beaver showing a higher salt tolerance in relation to germination and most of the seedling characters tested. On the other hand, Bronco was relatively, sensitive to salinity in relation to both germination and seedlings characters. The varietal differences in salt tolerance were not ascribed to differences in the cytoplasm and chromosome constitution.View full abstractDownload PDF (619K) -
Hitoshi SAKA, Akio KOGEN, Minoru OKUMURA, Shinichiro WATANABE1992 Volume 61 Issue 2 Pages 285-291
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSEthylene production and its fluctuation in panicles and flag leaf blades in the rice plant (Oryza sativa L.) during the grain ripening stage were examined. The effect of plant growth regulators (growth retardants and brassinosteroids) on fluctuating ethylene production in rice panicles were also investigated. The results are summarized as follows: (1) Ethylene production was readily determined by excising and incubating 2 to 3 panicles and flag leaf blades of rice for 24 h in a test tube stoppered with a serum cap. Under these conditions, ethylene production in ripening panicles increased significantly when exposed to light (about 30 μE·m-2·sec-1) as compared to conditions of darkness. However, light exposure reduced ethylene production below the levels achieved in darkness in flag leaf blades in contrast to the results with panicles. (2) Light-stimulated ethylene production in the panicle fluctuated during grain ripening, reaching its maximum rate of production at the milk-ripe stage. Lower rates were observed before and after the milk-ripe stage. (3) A high rate of ethylene production was maintained in the flag leaf blade until the milk-ripe stage, followed by a rapid decrease in subsequent stages. (4) In greenhouse experiments, the application of plant growth retardants (paclobutrazol and GRH-624) and brassinosteroids (brassinolide and epibrassinolide) several days prior to heading resulted in increased panicle fresh weight with concomitant increases in ethylene production as compared to control at the milk-ripe stage. The data suggest that light-dependent ethylene production in rice panicles is related to the different maturation stages following anthesis and fertilization in the rice plant.View full abstractDownload PDF (755K) -
Katsumi SUZUKI, Takeshi TANIGUCHI, Eizo MAEDA1992 Volume 61 Issue 2 Pages 292-303
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSUp to 12 h after anthesis (HAA), the first cell division in rice zygotes occurred with the formation of a slightly oblique transverse wall, causing the partition of the zygote into an apical cell and a basal cell. At 18 HAA, the partition in the apical cell was brought about by the presence of a longitudinal wall and in the basal cell by a transverse wall, which resulted in the formation of a four-celled embyro. At 24 HAA, the middle cell of the four-celled embryo was partitioned by a longitudinal wall, and the basal cell was again partitioned by a slightly oblique transverse wall. At 30 HAA, the apical and middle regions had four cells each with the further formation of longitudinal walls, so that the embryo became ten-celled. After that, cell division was directed at random. Well-developed cytoplasm existed around nuclei in proembryo cells. The cup-shaped plastids containing starch grains, the cup-shaped mitochondria, and the stratiform type of rough endoplasmic reticula were frequently observed. Many vacuoles were seen in the peripheral cytoplasm. The basal cells were more vacuolated than the cells at the upper side of the proembryo. At 18 HAA, the persistent synergid completely degenerated, involving electron dense materials. The endosperm became cytoplasm rich around the proembryo, especially after the embryo had started to increase in size.View full abstractDownload PDF (3250K) -
Tomomi NAKAMOTO, Akio MATSUZAKI, Kazuo SHIMODA1992 Volume 61 Issue 2 Pages 304-309
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe development of two-dimensional root distribution was studied with the generally-used profile wall method for field-grown cereal plants. Root length density was determined in each 5×5 cm area of a 1×1 m profile wall transverse to plant rows. Foxtail millet had a type of root system in which the root length density decreased exponentially with distance from row both vertically and horizontally. Barnyard millet had a shallow and broad rooting zone in which the root length density was high and considerably uniform. The other species fell in between these extremes. The order of foxtail millet, maize, common millet, pearl millet, adlay, barnyard millet, based on root distribution patterns, was in accordance with the decreasing order of sensitivity to waterlogging. The possible relationship of root spatial distribution to ecological habits was indicated.View full abstractDownload PDF (610K) -
Kengo INABA1992 Volume 61 Issue 2 Pages 310-311
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (355K) -
Michio YATOMI, Fumitake KUBOTA, Waichi AGATA, Masahiro MOROKUMA1992 Volume 61 Issue 2 Pages 312-313
Published: June 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (358K)
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