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Volume 61, Issue 1
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Hiroshi EHARA, Mikio TSUCHIYA, Hitoshi NAITO, Tatsuo OGO1992 Volume 61 Issue 1 Pages 1-9
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe effect of temporally high N application was investigated to develop the fertilization method that increases N content per leaf area (NCLA) without the increasing of specific leaf area. The change of N content in seedlings treated with high N concentration (230, 1150, 2300, 4600, 11500 and 23000 ppmN) for 12-24 hours, the effect of this treatment prior to transplanting on the growth after transplanting and the yield were analyzed. The result showed that 2300 ppmN 12 hours treatment did not affect leaf thickness, but increased NCLA by 40%. Seedlings treated with this treatment and transplanted at lower level of basal dressing showed remarkable acceleration of net assimilation rate, relative growth rate (RGR) and relative leaf growth rate. From the result of field trial under lower level of soil fertility condition, varietal differences were found in effect of this treatment, dry matter increased by 5-90%, tiller number increased by 10-90% at the early stage of the growth. However, the effect of this treatment was not found in plant length of all varieties used. It was considered that this treatment affected the growth directly for 3 weeks, based on the change of RGR. Moreover, increased tillers were lower order ones which were to be productive culm, clearly, the increasing of tiller number induced yield increase through the increasing of spikelet number per hill.View full abstractDownload PDF (899K) -
Hiroshi EHARA, Mikio TSUCHIYA, Yoshihiko HIRAI, Tatsuo OGO1992 Volume 61 Issue 1 Pages 10-15
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSTo make clear the internal leaf morphology concerned with varietal difference in specific leaf area (SLA) response to concentration of culture solution at the seedling stage, varietal differences in leaf morphological change with the advance of leaf position and in the response of leaf morphogenesis to nutrient concentration were investigated. Vascular bundle number (VBN) in transverse section of leaf blade and leaf width increased with the advance of position, but VBN did not increase with leaf width. Increase of leaf length with the advance of position was the greatest in NNN-type wherein nitrogen content per leaf area (NCLA) increased but SLA did not increase with nutrient concentration increase. The increase of VBN and leaf width in NNN-type were less than others. However, exceptionally in Dular, which was a variety in SSN-type wherein SLA increased with nutrient concentration, the VBN did not increase with nutrient concentration and was much more than others at every concentration. In the relationship between leaf width and length, leaf area expansion of NNN-type depended on leaf length, but others depended on leaf width increase. From these results, it was clear that SLA increase with heavy fertilization was extremely large in the varieties having many VBN by nature, and getting remarkable increase of VBN in response to fertilizer increase. Then, presumably, to improve rice productive ability efficiently in connection with fertilization, it is important that varieties have the characters, i.e. VBN and leaf width do not increase, leaf area expansion depends on the increase of leaf length, and moreover leaves are erect even under heavier fertilizer conditions.View full abstractDownload PDF (700K) -
Mikio TSUCHIYA, Hitoshi NAITO, Hiroshi EHARA, Tatsuo OGO1992 Volume 61 Issue 1 Pages 16-21
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSUsing two varieties, KR1 (salt-tolerant variety) and IR28 (salt-sensitive variety), relationship between Na+ uptake and transpiration under different humidity and salinity conditions was examined. The Na+ content of seedling increased more under lower humidity condition, and the tendency was sharper in IR28. The Na+ content changed with transpiration rate in both varieties. Transpiration stream concentration factor (TSCF), which denotes the ratio of ion concentration in the transpiration stream to that in the medium, decreased with the increase of transpiration rate. These results indicated that transpiration rate affected the filtration efficiency of roots in the Na+ uptake and transport to top. The lower TSCF of IR28 at the same transpiration rate suggested that the filtration efficiency was essentially higher in IR28. However, at the same NaCl concentration and air humidity condition, KR1 maintained comparatively higher transpiration rate, and consequently kept lower TSCF. It was supported with high leaf area ratio, high leaf water content and small stomatal resistance. These results indicated that the filtration efficiency in Na+ uptake depending on the transpiration rate under salinity condition was closely related to the difference of salinity tolerance between KR1 and IR28. It was suggested that plant characteristics on the filtration efficiency in Na+ uptake and the stability in water balance to environmental change might determine a passive Na+ uptake and transport to top under salinity condition.View full abstractDownload PDF (721K) -
Tadashi TAKAHASHI, Kimio NAKASEKO1992 Volume 61 Issue 1 Pages 22-27
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThree spring wheat varieties, old tall Haruhikari and modern semi-dwarf Haruyutaka bred in Hokkaido, and tall late Selpek bred in Germany, were sown at a 5cm equi-distant square pattern on 3 sowing dates, i.e. early (April 11), middle (April 25) and late (May 10). Varietal difference in yielding ability with delaying of sowing dates was investigated through changes in growth phases, process of spikelet initiation and crop growth rate. The first growth phase, from emergence to the double ridge, stage and the total growing period were shortened with delaying of sowing dates in all varieties. The spikelet initiation phase was also shortened resulting in a decrease of spikelet number. CGR and NAR in the late grain filling period (growth phase V) decreased with delaying of sowing dates, resulting in a decrease of final biomass. Grain yield decreased with delaying of sowing dates in all varieties, mainly due to the decrease in biomass and grain number. The extent of decrease of grain yield was smaller in Selpek than in the other two varieties ; the late sowing yielded less than the early sowing by 34% in Haruhikari, 36% in Haruyutaka and 14% in Selpek, because ear and spikelet number and CGR for grain filling period did not decrease with delaying of. sowing dates in Selpek. At late sowing dates, the grain yield was 418gm-2 in Haruhikari, 523gm-2 in Haruyutaka and 551gm-2 in Selpek. Ear weight type variety (e.g. Selpek) may be useful for late sowing cultivation in Hokkaido.View full abstractDownload PDF (719K) -
Toshirou HORINO, Tadahiko FUKUOKA, Takashi HAGIO1992 Volume 61 Issue 1 Pages 28-33
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSWe investigated chemical composition of cereals (rice, foxtail millet, barnyard millet, proso millet, sorghum for food, sorghum for feed, Job's tears, wheat, barley), buckwheat (common buckwheat) and pulses (small red bean, kidney bean, soybean). Kjeldahl-digested materials of powdered whole kernels of 719 samples were analyzed by automated colorimetric procedure (Technicon auto-analyzer) for N and P contents. HCl solution (0.34N) extracts of powdered whole kernels of 719 samples were analyzed by Polarized-Zeeman atomic absorption spectrophotometry (HITACHI Z8000) for K, Mg, Ca and Mn contents. Most of the cereals for food (including buckwheat) which have a history of more than a thousand years in East Asia showed about 1.5 of Mg/K ratio in chemical equivalence. Wheat, barley and sorghum (for animal feeding) which originated from West Asia or Africa showed comparatively lower Mg/K ratio. Pulses had the lowest Mg/K ratio, i.e. approximately 0.4, because of high K content. These data suggest that the contents and balances of K and Mg in crop kernels are genetically controlled.View full abstractDownload PDF (695K) -
Kiyoshi TAKAHASHI, Peter B. KAUFMAN1992 Volume 61 Issue 1 Pages 34-40
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSWe investigated the role of each plant hormone in the internodal elongation of rice seedlings using japonica rice cultivar 'Sasanishiki', and deepwater rice cultivar 'Leb Mue Nahng 111, and 'Habiganj Aman VIII'. Rice seedlings were grown in the light conditions at 30°C and applied with various plant growth regulators : abscisic acid (ABA), benzyl-adenine (BA), brassinolide (BR), ethylene (ET), gibberellin-A3 (GA3), indole-3-acetic acid (IAA) and triazinone (TA). (1) Among the seven growth regulators, only GA3 induced internode elongation when applied alone. In japonica rice, the elogation was not induced when applied with low level of GA3 (10-5M∼10-6M). The elongation, however, was induced by GA3 (10-5M∼10-6M) in the presence of polyethylene glycol (PEG) or TA (gibberellin synergist). In the deepwater rice, low level of GA3 (10-5M∼10-6M) induced the elongation. (2) GA3 or BR stimulated the coleptile growth. GA3, BR or IAA promoted the mesocotyl growth. GA3 promoted the leaf growth. GA3 and ET stimulated the internode elongation but the BR or BA inhibited the internode growth. ABA produced both an inhibition and a promotion of the internode growth. This may be due to the stage dependent response of the internode to ABA. These results may suggest that the regulation mechanism of the internode growth may include both organ-specific steps and the common process to other organs.View full abstractDownload PDF (821K) -
Gen-ichi HIRAI, Noboru NAKAYAMA, Hiroyoshi CHUJO, Toichiro INANO, Taka ...1992 Volume 61 Issue 1 Pages 41-48
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe horizontal distribution of leaf temperature in a rice population of 40×40 meters was investigated with an infrared scanning thermometer under a high temperature and high solar radiation during the period from late-July to late-August. The results obtained are summarized as follows: 1. Either the west wind blowing from a paved road toward the rice population or the east wind blowing across the field was the predominant wind direction in the examined rice population. These winds formed some belt-like low-temperature areas (rice plant waving) on the surface of the rice population. The leaf temperature in the cross section of the rice plant waving was the lowest at the middle of the rice plant waving and increased with distance from the middle. The temperature at the middle of the rice plant waving decreased gradually from windward to lee side in the case of the west wind, but did not vary in the case of the east wind. 2. In the case of the west wind, leaf temperature increased from the border to inside of the population at the wind speed of less than 1m/sec, but it decreased with the distance from the bordering area at the wind speed of more than 1m/sec. In the case of the east wind, the leaf temperature varied little in the rice population irrespective of the wind speed.View full abstractDownload PDF (910K) -
Kiyoshi TAKAHASHI1992 Volume 61 Issue 1 Pages 49-55
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSOne of the japonica paddy rice (Oryza sativa L. 'Sasanishiki') was used as a material. The panicles were cut off when all of their tillers had completed headings so that the new shoots (NS), namely, the high nodal-position tillers (HNPT) started to grow. Total number of leaves (TNL) on main stem was 14.8. Each plant had 74.4 shoots including 51.0 HNPT. The number of elongated internodes (NEI) was 5±1 in every shoot produced before heading of main stem, whereas TNL of tillers was varied from 3 to 9. On the other hand, TNL and NEI decreased with the elevation of nodal position of HNPT. The number of non-elongated internodes (NNEI) was not varied so much as those of NEI or TNL. NNEI was 0 in the second (from the top) and the 3 rd tillers and also in almost all of the 4 th tillers. In the 5 th tillers, NNEI of the secondary, tertiary, and quartic tillers was 0, 1 and 2, respectively. This increase of NNEI may be due to the longer period of bud dormancy. Every prophyll internode which was located below the prophyll node became a non-elongated internode.View full abstractDownload PDF (881K) -
Noriyuki TANAKA, Jiro HARADA, Susumu ARIMA, Seizaburo SAKAI1992 Volume 61 Issue 1 Pages 56-61
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSEffects of Inabenfide (SERITARD), a gibberellin biosynthesis inhibitor, on root growth of rice plants was examined in main stems of cv. 'Reiho' grown under field cndition in 1989 and per hill and per culm basis in cv. 'Koshihikari' grown in pots in 1990. The chemical, 5 kg per 10 a equivalent, was applied under flooded condition, 40 days and 35 days before heading stage in 1989 and in 1990, respectively. Plant height and culm length were significantly shortened and grain yield increased by the treatment. As for the yield components, the number of heads per m2, percentage of ripened kernels and weight per thousand kernels increased, although the number of kernels per head decreased. The total number of primary roots increased in the main stems treated by Inabenfide. The number of 'stunted' roots, however, also increased and, as a consequence, that of elongated primary roots tended to decrease. On the contrary, the total length of roots including that of branch roots exhibited a remarkable increase by the treatment. The effect of Inabenfide on branch root formation was also examined in the work. The ratio, the length of branch roots per unit length of primary root, increased by the treatment, although the root dry weight per unit length of total roots decreased, both indicating that the branch root formation was markedly promoted. Futhermore, the low ratio of shoot dry weight per total length of roots was noticed in treated plants. In conclusion, it was assumed that Inabenfide affects the number of culm and formation of roots, especially of branch root, and thus the total length of roots per hill might increase owing synergistically to both the effects. Moreover, it was thought that the effects would change the construction of rice plant to a more favorable one for producing high grain yield, by a relatively massive root system.View full abstractDownload PDF (811K) -
Kuniyuki SAITO, Hiroyuki SHIMODA, Kuni ISHIHARA1992 Volume 61 Issue 1 Pages 62-73
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSCanopy photosynthesis was simulated by using the modified Horie's model (1981) on the basis of measured canopy structure (Fig. 1), light intercepting characteristics (Fig. 2, 3, 4, Table 1) and leaf photosynthetic characters (Table 2) to explain the differences of dry matter production between the two early and medium varieties, which were used in the previous paper, in the stage of panicle development and early ripening. By estimating the diurnal changes of direct and diffuse light intensity, diurnal change of canopy gross photosynthetic rate (Pg) and the daily sum of Pg, daily gross photosynthesis (Pgday), were calculated. From these calculations, the relations between total light intensity (L) and Pg, and also between daily solar radiation (JTD) and Pgday were obtained. The percentage of diffuse light (DQ%) influenced markedly on Pg. As with the decrease in DQ%, slopes of L-Pg curve were decreased. Pgday increased with increase in JTD, but decreased at the higher level of JTD from 20 to 25 MJ·m-2 due to decrease in DQ%. Relative differences of simulated crop growth rate (CGR) among varieties coincided with those of measured CGR. In order to clarify the varietal difference of dry matter production, Pgday was recalculated by the substitution of canopy structure, light intercepting characteristics and leaf photosynthetic characters between the early and the medium varieties, respectively. In the early varieties, Nanjing 11 showed higher Pgday at the panicle development stage as compared with Akihikari owing to larger leaf area index in spite of smaller leaf photosynthetic rate. In the medium varieties, higher rates of Pgday in Milyang 23 as compared with Nipponbare were due to higher value of slopes in the light-photosynthesis curve of single leaf at the panicle development stage, and due to mutual acceleration of Pgday among canopy structure and light intercepting characteristics at the early ripening stage.View full abstractDownload PDF (1378K) -
Toshiro KURODA, Tomoki UETAKA, Kenji KOHRI, Seiichi KUMANO1992 Volume 61 Issue 1 Pages 74-79
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThis study was conducted to investigate the characteristics in terms of the identification of the raceme order (RO) for flower and pod shedding in soybean plants (c.v. Tatisuzunari). The control plot was provided as the reference using the Wagner pots (1/2000 a) independently, whereas the shading treatment was made specifically during flowering period. In the control plot, the percentage of the shedding buds, flowers and pods reached 5, 28 and 66% respectively. It can be observed that the total amount of shedding tended to increase due to the shading of light, particularly so for the flower shedding. The flowering takes place in the short duration of 20 days after the initiation stage ; however, the shedding lasts for a fairly long period, ranging from the stage shortly after flowering initiation to the ripening stage. The flowering of the raceme starts orderly from the lower RO including zero-and 1st-order, and then extends toward higher RO. This flowering order can be recognized in the similar manner for the shedding, and each RO showed continuous shedding up to the ripening stage. The following five stages are able to describe the inherent transition of RO :Stage-1, flower shedding in lower RO ;Stage-2, flower shedding in higher RO ;Stage-3, pod shedding in lower RO together with flower shedding in higher RO ;Stage-4, pod shedding in higher RO together with flower shedding in higher RO and pod shedding in lower RO ;Stage-5, pod shedding in lower and higher ROs.View full abstractDownload PDF (712K) -
Kenji AKITA, Naomichi TANAKA1992 Volume 61 Issue 1 Pages 80-86
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThis study was carried out to examine the effects of planting density and planting patterns in reference to various characteristics at the panicle formation, heading and maturing stages in rice plants (Oryza sativa L., cv. Nipponbare). In square planting plots, the plan length at the panicle formation stage was the tallest at a 49 hills/m2 plot, at the heading and maturing stages it was taller in lower planting density plots. In row planting plots, the plant length decreased with increasing plant density. The number of culms of square planting plots was the largest at a 100 hills/m2 plot at the panicle formation stage and at a 64 hills/m2 plot at heading time. Those of row planting plots were the largest at the most dense plot (100 hills/m2). Top dry weights in square and row planting plots were maximized at plant densities of 64 and 100 hills/m2 at panicle formation and heading stage, and 49 and 100 hills/m2 at maturing stage. The highest panicle number was obtained at a 81 hills/m2 plot of square planting and at a 100 hills/m2 plot of row planting. The percentage of ripened grains was the highest at a 25 hills/m2 plot of square planting and at a 100 hills/m2 plot of row planting. As a result, the highest yield was obtained at a 49 hills/m2 plot of square planting, and at a 100 hills/m2 plot of row planting. It is suggested that the best planting density to obtain the highest yield in paddy rice may also depend upon planting patterns.View full abstractDownload PDF (669K) -
Katsumi INADA, Asana MATSUURA, Masakatsu YAMANE1992 Volume 61 Issue 1 Pages 87-95
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSInterspecific differences in drought tolerance were studied by two solution- and one field-culture experiments in a glasshouse using Japanese millet, sorghum, pearl millet and maize. Water stress treatment for the solution culture was achieved by adding polyethylene glycol 6000 to the solution at a final concentration of 200g/1000g H2O, producing a -0.93 MPa osmotic potential, while that for the field experiment was by suspension of watering. The treatment was made for about two weeks in the vegetative growth stage. Growth parameters and leaf water status were determined at the beginning, during and after the treatment. Dry weight of plant was generally decreased less by stress in pearl millet and sorghum, while the recovery after removal of stress was faster in sorghum and Japanese millet than in the other opecies. Osmotic potential (π) as against water potential (Ψ) in stressed leaves decreased more than in the control, except for maize. The decreasing order of relative water content with a decrease of either Ψ or π was as follows : maize>Japanese millet>sorghum>pearl millet. Osmotic adjustment (OA) increased in the following order : sorghum>Japanese millet>pearl millet>maize. From these results, we concluded that sorghum and Japanese millet, especially sorghum, possess a higher dehydration tolerance due to a higher OA and pearl millet due to a larger water retention ability, whereas maize easily wilts because of a smaller OA and water retention ability.View full abstractDownload PDF (776K) -
Souhei SAWADA1992 Volume 61 Issue 1 Pages 96-100
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSExperiments were carried out to elucidate the time at which the leaflet shape was determined during growth, and to evaluate the extent of variation of leaf shape within and between plants in soybean. Two cultivars, "Kitakomachi" (broad type) and "Isuzu" (narrow type) and one line "Toiku 187" (intermediate type) were used. Leaflet shape was represented by LSI (leaf shape index). Leaflets determined their shape at early stages of growth, when the length and width of the leaflets of the three genotypes reached 40-60% of their maximum size. Left and right leaflets of each leaf on the main stem had almost the same shape, but their LSI values were smaller than that of central leaflets in all three genotypes. LSI values from the bottom to the top on the main stem differed between genotypes. The extent of variation of the LSI between plants in Kitakomachi was the smallest among the three genotypes, while that in Isuzu was the biggest. A LSI value of 2.6 can be used as a criterion for classifying broad and narrow types of leaf shapes, but further investigations are necessary to clarify the behavior of the intermediate type.View full abstractDownload PDF (514K) -
Shigenori MORITA, Suthep THONGPAE, Jun ABE, Tomomi NAKAMOTO, Koou YAMA ...1992 Volume 61 Issue 1 Pages 101-106
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSRoot branching in maize (Zea mays L. cv. Pioneer 3558) at harvest stage was examined, with the "branching index" defined as the product of the 'length factor' and 'density factor'. "Branching index" was very effective to characterize the remarkable differences in branching degree of primary roots from different nodes. It was also shown that "branching index" seemed to depend on 'length factor' much rather than 'density factor'. The analysis on the branching degree with reference to primary root diameter suggested a possible relation of 'density factor' to the surface area of primary roots where 1st-order branch roots emerged and that 'length factor' might depend on other factors. And methods for measuring root length were compared with one another. Root length measurements by the root length scanner were quite reliable, based on the assumption that the intersection method would be a standard. The image analyzing system was also useful to measure root length as classified by its diameter.View full abstractDownload PDF (625K) -
Hiroshi SUGE1992 Volume 61 Issue 1 Pages 107-111
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIn Perilla plants, grafting experiments gave evidence that endogenous gibberellin was not involved directly in the differentiation of floral primordia, but that it plays an important role in the development of floral organ once it has differentiated. Graft of inflorescence, 3-4cm long and in the development stage, onto vegetative receptor stock plant was found to induce flowering on 21.4% of receptor stock plants. This indicates the retention of floral stimulus in floral organ.View full abstractDownload PDF (634K) -
Yoshie S. MOMONOKI, Tokuhiro MOMONOKI1992 Volume 61 Issue 1 Pages 112-118
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIn this work, the changes in ACh-hydrolyzing activity and ACh content in plant tissues of Macroptilium atropurpureum cv. Siratro following leaf wilting and leaf recovery after heat stress and the effects of exogenous ACh, K+ or Ca2+ on detached and heat-stressed leaves to which the primary pulvinus was still attached were determined. The ACh-hydrolyzing activity was 75 nM ACh mg-1 dry weight in the primary pulvinus and 46 nM ACh mg-1 dry weight in the secondary pulvinus, and was 4∼12 fold higher than found in the leaf, petiole, stem or root. Heat stress increased the ACh-hydrolyzing activity about 4 fold and 2 fold in the primary and secondary pulvini, respectively. The ACh-hydrolyzing activity was inhibited about 96% by neostigmine bromide. The content of ACh in the primary and secondary pulvini also changed dramatically within 3 min after heat stress. The changes of ACh content and ACh-hydrolyzing activity in plant tissues were then found to be correlated with leaf drooping and leaf recovery. Additionally, the application of ACh together with K+ or Ca2+ salts remarkably enhanced leaf recovery from wilting in detached and heat-stressed primary pulvinus leaves. The results suggest that ACh may control ion or hormone fluxes regulating the opening of ion channel in pulvini.View full abstractDownload PDF (762K) -
Atsushi OYANAGI, Akiko SATO, Michihiro WADA1992 Volume 61 Issue 1 Pages 119-123
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIt has been observed that wheat has a shallow root system in wet soil and a deep root system in dry soil. However, the control mechanisms of root growth depending on soil water status remain unclear. Since root geotropic response seems to play an important role in the formation of the root system, the effect of water potential of culture medium on the geotropic response of the primary seminal root in Japanese wheat cultivars was examined. Agar medium with different concentrations of polyethylene glycol (PEG-6000) and vermiculite medium with different levels of water content were used. Growth angle of the primary seminal root in Minaminokomugi, which usually shows small root growth angle, became larger in low water potential media (-0.05 MPa) than in the control (O MPa). Effects of low water potential on root geotropic responses in the agar medium were also examined in 133 Japanese wheat cultivars. Minaminokomugi and 50 other cultivars showed large responses in the low water potential medium. It is considered that low water potential of the culture medium stimulates positive root geotropic responses in certain Japanese wheat cultivars.View full abstractDownload PDF (530K) -
Akihiro ISODA, Takao YOSHIMURA, Toshio ISHIKAWA, Hiroshi NOJIMA, Yasuo ...1992 Volume 61 Issue 1 Pages 124-130
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIntercepted solar radiation by each leaflet in two field grown soybean communities was measured by integrated solarimeter films for two consecutive days. These solarimeters are pieces of film (70 mg, 12 mm×35mm), and measure radiation by percentages of remaining dye after the exposure to radiation. These solarimeters were placed on every leaflet surface of two plants each of the two determinate cultivars. The experiments were done at the flowering and the young pod stages. In both experiments, the mean intercepted radiation of each layer tended to be decreased gradually toward the base of the canopy. There were several leaflets which intercepted similar radiation as compared with the global solar radiation. The portion of intercepted radiation by leaves on branches was about 60% of the total intercepted radiation at the flowering stage, and increased to about 70% at the young pod stage. Terminal leaflets intercepted more radiation ranging from 4 to 10% as compared with the side leaflets.View full abstractDownload PDF (815K) -
Tadachika OOTA, Katsuhiro WAKABAYASHI, Katsu IMAI1992 Volume 61 Issue 1 Pages 131-135
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe time-course change of dark respiration and the maintenance component of respiration in corn seedlings were studied by the starvation method. In the dark, leaf growth at the 4, 5 and 6th positions from the 14, 21 and 28 day-old plants ceased by 96- 120 h. The time-course change of dark respiration was divided into three phases : initial rapid decreasing phase (<10 h), gradual decreasing phase (10-84 h) and non-decreasing phase (84 h<). During the 84- 120 h of darkness, shoot respiration attained steady levels (1.06-0.84 mg g-1 h-1 at 2°C). It was inferred from above two observations that the respiration at 96-120 h measured by IRGA was equivalent to maintenence component for corn seedlings. Younger plants were estimated to have a lower proportion of maintenance component to total respiration than older ones at the initial stage of darkness (10 vs. 18%). The dark efflux of 14CO2 from current photosynthates supported these findings.View full abstractDownload PDF (621K) -
Tomikichi WADA, Tatsuya ITO, Masaaki ITO, Yoji TAKEOKA1992 Volume 61 Issue 1 Pages 136-144
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDevelopment of pollen cells as well as the fate of tapetal cells were studied by the glycol methacrylate semithin method for light microscopy. Sections including artificially produced images of pollen cells were eliminated and some probale backgrounds of these images were discussed. The spatial close interrelationship between developing pollen and tapetal cells was found to be maintained up to mature pollen. Germ pore was observed mostly pointing toward the tapetal side instead of being constantly appressed tapetum. Degeneration of the tapetum seemed to be related to the development of microspore. Storage process of engorged pollen and easy release of mature pollen were seen to be accompanied by probable water decrease in the anther loculus.View full abstractDownload PDF (1731K) -
Tadashi HIRASAWA, Masanori TSUCHIDA, Kuni ISHIHARA1992 Volume 61 Issue 1 Pages 145-152
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThere was considerable difference in the degree of the midday depression in the stomatal conductance, and the photosynthetic rate among rice plants grown under different conditions, and the degree of the midday depression was supposed to depend on root-water uptake ability. The present study was conducted to investigate the difference in the exudation rate under practically zero transpiration, representing active water uptake capacity, and in the resistance to water transport under intense transpiration, representing passive water uptake capacity, among rice plants grown under different conditions. The relationship between passive and active water uptake capacities as well as between the passive water uptake capacity and the degree of midday stomatal closure was also investigated. In the plants in which "root-rot" occurred as a result of the soluble starch added to the soil and in those which were grown under the conditions of low light intensity and high humidity and developed a smaller root system, the exudation rate was low and the resistance to water transport was high compared to the control plants. This means that active and passive water uptake capacities were lower in these plants than in the control plants. In the plants which were grown on the culture solution of low nitrogen level and developed larger root system, exudation rate was high and the resistance was low compared to the plants grown on the standard culture solution, that is, active and passive water uptake capacities were higher in the former than in the latter. The degree of the midday depression in the stomatal aperture was larger in the plants in which resistance to water transport was larger and there was a close correlation between the resistance, i.e. passive water uptake capacity, and the degree of the midday depression. On the other hand, in the plants whose leaf nitrogen content was increased by applying ammonium sulfate one week before measurement commenced, exudation rate increased markedly but the resistance to water transport did not change. The stomatal aperture was far larger in the plants supplied with additional ammonium sulfate than in the control plants in the morning, but the difference in the sizes of these respective stomatal apertures became smaller under intense midday transpiration because of the absence of any difference in their passive water uptake capacities. In view of the high correlation between gas exchange rate through stomata and photosynthetic rate, these results suggest that higher passive water uptake capacity is essential, in addition to the increase in leaf nitrogen content, in increasing the daily total photosynthesis.View full abstractDownload PDF (910K) -
Tadashi HIRASAWA, Toshiyuki GOTOU, Kuni ISHIHARA1992 Volume 61 Issue 1 Pages 153-158
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe degree of the midday depression in the stomatal conductance and the photosynthetic rate is larger in the lower leaves than in the upper leaves on a stem. It was clarified in the previous report that resistance to water transport correlates closely with the degree of the midday depression in the stomatal conductance. The present study was to investigate the difference among the resistances to water transport from root surface to leaves (whole resistances to leaves) at different positions on the stem and also to investigate the factors related to the difference among the whole resistances to the leaves. The whole resistance to the older leaves at the lower position on the stem was larger than that to the younger leaves at the upper position. There was no significant difference among the whole resistances to the leaves of the same age. The whole resistance to each leaf increased considerably after the leaf had fully expanded. It was concluded that the longer the time elapsed after the full leaf expansion, the higher the whole resistance to the leaf at the lower position of the stem. The increase in the resistance from the base of a stem to the leaf measured by using the excised stem was far smaller than that in the whole resistance. Since older leaves and younger leaves were closely connected with older crown roots and younger crown roots, respectively, it was suggested that an increase in the whole resistance to thc leaf with time after full leaf expansion might result from the increase in the resistance of the roots connected with the leaf, i. e. the reduction in passive water uptake capacity of the roots due to age of the roots. Also, the larger midday depression in the stomatal conductance of the lower leaves was supposed to be due to the larger whole resistance to them. Moreover, it was also found out that resistance to water transport in the stem and the leaf is the dominant resistance in the whole plant resistance when the leaf had just expanded fully. The ratio of the root resistance to the whole resistance, however increased considerably with age of the leaf.View full abstractDownload PDF (699K) -
Tatsuro HIROSE, Takeshi IZUTA, Hiroshi MIYAKE, Tsumugu TOTSUKA1992 Volume 61 Issue 1 Pages 159-160
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (429K) -
Akihiro NOSE1992 Volume 61 Issue 1 Pages 161-171
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (1288K) -
[in Japanese]1992 Volume 61 Issue 1 Pages 174-178
Published: March 05, 1992
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (623K)
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