All issues
Volume 64, Issue 1
Displaying 1-25 of 25 articles from this issue
- |<
- <
- 1
- >
- >|
-
Tomohiko YOSHIDA, Sakiko HOZONO1995 Volume 64 Issue 1 Pages 1-6
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe yielding ability and the effect of fertilization on yield were investigated in ratoon crop rice in early-season cultures. The total leaf number of each tiller in the ratoon crop was compared with Katayama's theoretical total number of leaves. The ratoon crop produced about 30% of the grain yield of the parent crop. Fertilization of the ratoon crop increased the panicle number per hill, resulting in an increased yield. Ratoon tillers were separated from the main stem to determine their tillering position on the stem, and to find the effect of fertilization on regrowth of tillers. Yield increase by fertilization was mainly due to the increase in the number of ripened secondary tillers. Tillers had 2∼3 more leaves than the total leaves expected from the theory of synchronous growth of leaves and tillers. The investigation of growth of lateral buds at each growth stage of the parent crop showed that the relation between growth of the main stem and lateral bud growth of ratoon tillers was not synchronized, resulting in the increase of total leaf number over the theoretical one.View full abstractDownload PDF (706K) -
Koichi YOSHIDA, Hisayasu SATO, Michinori SATO1995 Volume 64 Issue 1 Pages 7-13
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSWater uptake of seeds and hardseededness under 27°C soaking in adzuki bean (Vigna angularis) cv. Erimo-shozu were evaluated for seedlots (a total of 544 growers) collected from four districts in Hokkaido (42-45°N lat) from 1987 to 1989. For comparison, the other cultivars and soybean cv. Kitahomare also were investigated in 1987. The change with time in percent water uptake (PWU) of adzuki bean seeds displayed a sigmoid curve ; seeds absorbed water very slowly by 5% (cf. 85% in soybean) at 4 h of soaking, quickly through 12 h, and slowly again after 24 h. Differences in PWU were remakable after 12 h of soaking with higher percentages in smaller-seeded cultivars. There was a greater difference between years in PWU than among districts. These differences, however, mostly disappeared after 24 h. Seed size, moisture content, and specific gravity were not closely related to PWU after 12 h, although significant negative correlations were found in some cases. Percent hard seeds (PHS), evaluated after 36 h of soaking, varied in the ranges 0-13%, 0.35-0.74%, and 0.06∼1.21% among individual seedlots, districts, and years, respectively. Within or between seedlots, smaller seeds tended to become hard. Seed characteristics such as moisture content, percent seed coat, and specific gravity, and conditioning period were rarely associated with PHS. Also, the relationship between mean day temperature or rainfall during the reproductive period and PHS was unclear in this investigation.View full abstractDownload PDF (836K) -
Shigenori MORITA, Hiroyuki OKUDA1995 Volume 64 Issue 1 Pages 14-18
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSGrowth and development of seminal and nodal roots in wheat were examined. After the experimental site was plowed and fertilized, a Japanese wheat cultivar was planted. Root system distributed in the top 30 cm of soil was taken using the monolith method every 2 weeks throughout the growing season. In each sampling, all seminal and nodal roots of three selected plants with normal size were identified and the number of root axes were recorded. Then the length of the root axes and the total root length including all lateral roots were measured, and the branching degree was examined as well. The total number and length of root axes in the seminal roots increased and almost reached a constant value soon after planting. The total root length of seminal roots, on the other hand, increased thereafter due to well-developed root branching, reached a maximum value and then decreased becouse of possible loss of lateral roots. On the contrary, the total number and length of nodal roots on main stems increased in the later growth stages followed by development of nodal roots emerged from tillers. Root branching of nodal roots was poorly developed compared with seminal roots. In the former growing period, most shallow roots consisted of seminal roots with well-developed laterals, whereris nodal roots increased to occupy a large portion in the later stages because of the increase in the total number of nodal roots as well as the decrease in the total length of seminal roots.View full abstractDownload PDF (661K) -
Yixin SHEN, Koji ITO, Yasuyuki ISHII, Shigeyuki TANAKA, Noriyuki TANAK ...1995 Volume 64 Issue 1 Pages 19-26
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe changes in growth of orchardgrass, Dactylis glomerata L., cv. Natsumidori as affected by previous fertilization were investigated in field and pot trials. In the field trial, the seeds were sown on 0ctober 31, 1991 and three fertilization plots were set up on January 5, 1992 by broadcasting a chemical fertilizer (N : P2O5 : K2O= 15% : 15% : 15%) at the rate of 66.6, 33.3 or 0 g/m2. Additional fertilization was done for all plots using the same fertilizer at an equal rate of 33.3 g/m2 on April 15 and then a half of plants of each plot were cut to a height of 3 cm. Changes in growth were observed from January 5 to April 14 (the first period) and from April 15 to May 25 (the second period). In addition, similar treatment and observation were made in the pot trial in 1993. As the direct effects of the ferfilization at the beginning of the first period, tiller production, the leaf extension rate, leaf area index (LAI) and the dry matter yield of the aerial part decreased along with the fertilization fate. However, for both non-cut and cut plants, dry matter production rates during the second period was higher in the plot given less fertilizer during the first period. This strongly suggests that a compensatory growth occurred in the second period due to the fertilizer deficiency in the first period. Such compensatory growth may have resulted from the stimulation of daughter tiller production and leaf growth of each tiller, which in turn brought about a higher LAI and net assimilation rate in the plot given less fertilizer in the first period.View full abstractDownload PDF (863K) -
Seiji ITO, Akiko SATO, Tsuguhiro HOSHINO1995 Volume 64 Issue 1 Pages 27-32
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThirty Tohoku and 30 foreign wheat cultivars were grown under the same cultivation condition and were analyzed about milling quality. Wheat cultivars were classified into the small group and the large group based on the specific surface area (SSA). The small group was big particle size of A flour and high milling rate, and the other group was small and low. Namely, the small group is considered to be hard wheat and the large group is considered to be soft wheat. The classification of cultivars based on the A flour rate coincides with the classification based on SSA. In the hard wheats, the higher regression coefficient of flour yield rate to SSA was higher than in the soft wheats. It is shown that the effect of selection by SSA in milling characteristics was higher in the softwheats than that in the hard wheats. The hard wheats differed with the soft wheats in the milling characteristics. It is necessary that the examination of milling characteristics of wheat cultivar has to be conducted in the same hardness group.View full abstractDownload PDF (655K) -
Hiroshi NAKAGAWA, Takeshi HORIE1995 Volume 64 Issue 1 Pages 33-42
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSUnder the hypothesis that environmental responses of ontogenetic development of rice are different before and after panicle initiation (PI), a model for simulating rice panicle development and heading date was synthesized. In this model, the values of the developmental index (DVI) which is a continuous variable representing rice development stage are defined to be 0 at the emergence, 1.0 at Pl and 2.0 at the heading, respectively. Under this defining condition of DVI, we determined, for each developmental phase before and after Pl, the values of parameters of the equation giving the developmental rate (DVR) as a function of daily mean temperature and photoperiod, by using the Simplex method and rice phenology data. Field experiments on three cultivars of Nipponbare, Koshihikari and IR36, in Kyoto over four years using a range of sowing dates in each year, provided data for the parameter estimation and model validation. The values of parameters thus obtained suggested that DVR responses to temperature and photoperiod are different between the vegetative and reproductive development phases. The model explained dates of PI and heading of the three cultivars more accurately than the previous model, in which DVR responses to the environment were assumed to be unchanged before and after the PI. A close correspondence was observed between the DVI values calculated by the model and the morphological development stage of rice panicle, irrespective of environmental conditions and cultivars, suggesting that the model is applicable for the prediction of the panicle development from environmental conditions.View full abstractDownload PDF (954K) -
Satoshi NAKAMURA, Yusuke GOTO, Kiyochika HOSHIKAWA1995 Volume 64 Issue 1 Pages 43-49
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe harvest object of a sweet sorghum plant is all parts of shoot which mainly consists of a juicy main stem, leaf blades and leaf sheaths. To obtain higher yield, it is important to understand in detail the yield production process. However, little has been known about plant age for sweet sorghum, which is an important parameter to predict the growth patterns of elongated internode (IN : defined as that having≥1.0cm), leaf blade (LB) and leaf sheath (LS). Thus, here we developed a new index of plant age (AL) by using the position of a fully expanded leaf on the stem. This study was conducted to clarify the elongation patterns of IN, LB and LS. Two cultivars, Syrup sorgo 2 (S2, a late-maturing) and Hybrid sorgo (HS, a medium-maturing), were gorwn under the field condition in 1992. A conceptional growth curve of IN, LB and LS was drawn by plotting their percentages of elongation on AL. IN (n) (n : natural number) began to elongate at AL(n+1), rapidly elongated at AL(n+2) and reached its maximum length at AL(n+3)∼AL(n+4). LB(n) rapidly elongated at AL(n-4)∼AL(n-2) and reached its maximum length at AL(n-1). LS (n) rapidly elongated at AL(n-1), reached its maximum length at AL(n)∼AL(n+1). Thus, AL can serve as an effective means of identifying the stage of IN, LB and LS development during the internode elongation stage.View full abstractDownload PDF (744K) -
Jiro TATSUMI1995 Volume 64 Issue 1 Pages 50-57
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIn order to describe root distribution quantitatively, fractal analysis was applied to root systems. Root systems of soybean and garden pea seeldings grown in narrow root boxes (30×41×2 cm) were sampled with minimum disturbance of root arrangement using the root box-pin board method. Root samples were taken on 15, 25 and 41 days after sowing for soybean and 30, 55 and 94 days after for graden pea. The harvested root system was spread on the scanner bed connecting to a personal computer (Macintosh IIcx), and the root image was digitized with a 256 gray scale and 144 DPI resolution. Each image stored on a magneto-optical disks loaded on a MO disk drive (Reo drive, Yano Electric) was analyzed by the NIH Image software (ver. 1.5) running on a Macintosh computer (Quadra 800). The fractal dimension (D) of root images was estimated by counting the number of pixels constituting root image at various resolutions (box-counting method). D increased as the root system developed. D of the lower half (Dl) increased slowly compared with that of the upper half. This changing pattern of Dl corresponds well to the slower development of roots into the lower soil layer. The linear positive correlations were found between D and total root length (L) and between D and root projection area (PA). The correlation coefficients between D and L, and between D and PA were lower than that between L and PA. In soybean correlation coefficient between D and L was lower than graden pea, particularly in the lower half of the root system. These results indicate that fractal analysis is applicable to root systems, and that the D can be an effective parameter describing root morphology quantitatively.View full abstractDownload PDF (851K) -
Shigenori MORITA, Shohei YAMADA, Jun ABE1995 Volume 64 Issue 1 Pages 58-65
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe morphology of the rice root system was established by analyzing varietal differences. Four rice varieties, Koshihikari, Dobashi 1, IR36 and Lemont, were grown in an experimental paddy under ordinary condition. Soil monolith were taken from the direct-foot of a hill and from the midpoint among hills at the ripening stage. After washing out roots carefully, the length and the weight of roots at different soil depths were measured. The number and the growth angle of nodal roots were also examined in the same four varieties. With these data, the root amount and the 'root depth index' as an index of root distribution were calculated. The root system morphology of the four varieties were quantitatively characterized with these two indices : Koshihikari has a root system with a small amount and a shallow distribution, Lemont large amount and deep distribution, IR36 large amount and shallow distribution, and Dobashi the moderate of these three other varieties, respectively. Furthermore, it was shown that the root amount was determined by the combination of the number of nodal roots and the 'mean root length' (the mean length of a nodal root including the lateral roots of any order). The 'root depth index', on the other hand, was determined by the combination of the mean growth angle of nodal roots and the 'mean root length'. The contribution of these determining factors differed among cultivars. For instance, the large root amount depended on the large number of nodal roots in IR36 and on the large 'mean root length' in Lemont, respectively. The deep distribution of roots in Dobashi 1 was due to large 'mean root langth' whereas to the large mean growth angle in Lemont.View full abstractDownload PDF (939K) -
Kiyoshi TAKAHASHI, Hajime WATANABE, Kiyochika HOSHIKAWA1995 Volume 64 Issue 1 Pages 66-72
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe characteristics of internode elongation were investigated using 262 rice cultivars including 260 from IRRI's core collection and two recommended Japanese cultivars, Sasanishiki and Koshihikari. Sterilized brown rice grains were planted on 0.8% agar medium under aseptic condition, and incubated in a growth chamber at 30°C under total darkness for 14 days. The lengths of mesocotyl (ML), first internode (1IN), second internode (2IN), third internode (3IN) and total length of internodes (ML+1IN+2IN, TLI) were recorded. The frequency distribution of the final length of ML and 1IN was nonsymmetric whereas that of the 2IN and TLI was a nearly normal distribution. The mean length of ML, 1IN, 2IN, TLI, was 12.3±0.8 mm, 11.1±0.6 mm, 35.1±1.0 mm, 58.5±1.8 mm, respectively. Of all the cultivars, the 1IN did not elongate in 22 and the 3IN did not elongate in 88. Cultivars having longer TLI were hard to grow 3IN. The geographical distribution showed that there was wide variation in the length of the internodes of Southwest Asian cultivars : however, narrow variation was observed for East Asian cultivars. Correlation coefficients for ML vs 2IN, ML vs TLI, 1IN vs 2IN, 1IN vs TLI, 2IN vs TLI were positive and highly significant.View full abstractDownload PDF (810K) -
Lawrence Misa ABOAGYE, Akihiro ISODA, Hiroshi NOJIMA, Yasuo TAKASAKI, ...1995 Volume 64 Issue 1 Pages 73-77
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSEight peanut cultivars of the Virginia types (Chibahandachi and Chiba 43), Spanish type (Kintoki), Valencia types (Valencia, Tarapoto and Hotakuchuryu) and the types derived by crossing Virginia with Spanish types (Kanto 56 and Tachimasari) were investigated under field conditions to clarify the relationship between the canopy structure, its components and solar radiation interception. The Virginia types were of short stature, smaller leaflet areas, higher leaf area indices (LAI), greater leaf numbers and intercepted lower radiation per leaflet area. The Spanish and Valencia types were tall, had greater leaflet areas, lower leaflet numbers and greater intercepted radiation per leaflet area. The crossing types were of medium or low plant heights, leaflet area and LAI. Generally, the mean leaflet intercepted radiation was higher at each layer of the canopy in the taller cultivars and lower in the shorter cultivars. Kanto 56 was exceptional, with its lower plant height, medium leaflet size and LAI ; and intercepted greater amount of solar radiation.View full abstractDownload PDF (596K) -
Tadashi HIRASAWA, Masahide TAKEI, Kuni ISHIHARA1995 Volume 64 Issue 1 Pages 78-85
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIn order to develop a simple and accurate system for measuring the root system of soybean plants growing in the field, a fiber-optic scope with a portable color video tape recorder was employed in a minirhizotron system. A transparent acrylic tube of 60 mm outer diameter and 54 mm inner diameter as the observation tube was installed into the soil at an angle of 30° from the vertical. The accuracy and the utility of the system were examined. (1) The length of all tap and branch roots at the observation tube-soil interface was measured with an accuracy of 5% using this system. (2) The observation tube did not significantly disturb root penetration into the soil. This was also suggested by the results that the changes in root length with the increase of soil depth showed a reasonable tendency without an unusual increase or decrease. (3) There was a significant linear correlation between the root length measured with the minirhizotron system and the root length density measured by a soil-core sampling method in the plants growing in the field. However, variation in the measurements taken with the minirhizotron system was as large as those by the soil-core sampling method, indicating that the root distribution in soil was extremely non-uniform. From these results, it was possible to estimate root growth in the field well using this system. Moreover, taking as many measurements as in the soil-core sampling method, root distribution in the field can be estimated quantitatively with less labor and time with the minirhizotron system than the conventional method.View full abstractDownload PDF (828K) -
Kazuto IWAMA, 0SAMU TAKATA, Masatoshi 0HNAMI, Kimio NAKASEKO1995 Volume 64 Issue 1 Pages 86-92
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe relationships of root growth with shoot and tuber growths have still not been clear in potato plants. The aim of this report is to clarify whether a varietal difference in root growth of potato plants is determined by some inherent characteristics in the root organ per se, or affected by the growth of other organs. Four combinations of grafting plants between two late varieties, Norin 1 and Konafubuki, with different root mass were produced and cultured in large pot; (25 cm in diameter, 50 cm in depth) with plentiful water supply. Dry weight (DW) of each organ and leaf area were measured at three stages, just after the transplanting, approximately after the initial flowering and after the last flowering, for three years. Analyses of variance for the characters were performed using the years as replications. The stock genotypes significantly influenced root DW of the grafting plants at the three stages examined. The effects of scion genotypes on root DW were not significant. The negative relationship was found between root DW and tuber DW in the grafting plants. Shoot DW and leaf area were not significantly different among the grafting plants. We concluded that the difference in root DW between the two varieties was mainly due to the inherent characteristic in the dry matter partition to roots and tubers just after the tuber initiation.View full abstractDownload PDF (703K) -
Mikio TSUGHIYA, Miyuki MIYAKE, Philbert BONILLA, Seiichi KUMANO1995 Volume 64 Issue 1 Pages 93-101
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSIon exclusion in excised nodal root of rice (Oryza sativa L. cv. Kala-Rata 1-24) exposed to NaCl stress with hydraulic pressure was studied. The effects of collecting the exudate from the stele instead of the whole cut-surface of the root, making holes to penetrate the cell layers of the epidermis, exodermis and cortical sclerenchyma, and partial coating of root surface with epoxy resin on the ion exclusion rate were investigated under 20 mmol l-1 NaCl at 490 kPa. Na+ and Cl- concentrations of the exudate from the stele and whole cut-surface of excised sorghum and corn roots were also measured and their ion exclusion capacities were compared with rice roots. Moreover, the effects of hydraulic pressure, temperature, pH, dissolved air content and ion constituent in the solution surrounding the root, and metabolic inhibitors on the ion exclusion rate were investigated. The exclusion rate was the highest in corn, followed by sorghum then rice. It increased when exudate was collected from the stele and decreased when cell layers from the epidermis to cortical sclerenchyma were holed. It was higher in the older tissues of the root compared with the tip. Though high pressure led to a higher exclusion rate, high temperature and high pH degraded the roots and lowered the rate. Deaerated solution also decreased the rate. The exclusion rate of different ions was in the same order as the radius of the hydrated ion, i.e. Mg2+ > Ca2+ > Na+ > Cl- > K+. The roots treated with 0.5 mmol l-1 2, 4-dinitrophenol or sodium azide showed a negative linear corelation between the flow rate of the exudate and the Na+ exclusion rate. This suggests that the barrier against the inflow of ions broke down, consequently, that the ion selectivity of roots was lost.View full abstractDownload PDF (834K) -
Mikio TSUCHIYA, Philbert BONILLA, Seiichi KUMANO1995 Volume 64 Issue 1 Pages 102-108
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe objective of the study was to determine the varietal difference in ion exclusion of rice root exposed to NaCl stress under hydraulic pressure. A total of 10 varieties, namely eight indica i.e. Hsieh-Tso 12, IR4595-4-1-13, Jyothi, Kala-Rata 1-24 (KR1), Mangasa, Milyang 23, Pokkali, SEW 273-5-13 and two japonica i.e. Akebono and Asahi, were used. At the 8th leaf stage, 6∼8 cm excised nodal roots (5 to 6 d old) of each variety were submerged in a test tube with Kimura B nutrient solution containing 20 or 50 mmol l-1 NaCl (pH 5.5) and applied 294 or 686 kPa hydraulic pressure in a pressure chamber. The relative value, which is the ratio of ion concentration in the exudate to that in the medium, was used to indicate the ion exclusion rate. At both pressure levels, all roots of each variety exhibited ion exclusion capacity. Milyang 23 and SEW 273-5-13, both salt tolerant, and Mangasa, salt susceptible, remarkably increased their exclusion rate at higher pressure. In low or high pressure, Hsieh-Tso 12 and KR1, both salt tolerant, showed a high exclusion rate, while it was low in Pokkali and Asahi. Results showed that at the same flow rate of exudate, the ion fluxes of Na+, Cl-, and K+ were lower at the higher pressure. Also, at the high pressure, varieties with higher amounts of lignin in roots showed lower Na+ and Cl- concentrations in the exudate. These results clearly suggest the presence of negative pressure in the roots, which can be provided by transpiration or osmotic adjustment, will increase the salt exclusion rate.View full abstractDownload PDF (769K) -
Zheng-Jun Xu, Kaien FUJINO, Chihiro FURUYA, Yoshio KIKUTA1995 Volume 64 Issue 1 Pages 109-114
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSSome physiological changes induced by abscisic acid (ABA) were investigated in a long-term cultured callus of rice, Oryza sativa, L. cultivar YUHKARA. The results were as follows : (1) The retardation of callus growth was evident, while dry matter content was apparently increased with the addition of abscisic acid (ABA). (2) Soluble protein content was increased both in fresh weight and dry matter bases. (3) The novel proteins (14, 18.5, 25, 45 kDa) were induced by ABA and disappeared after plantlet regeneration, while proteins of the same molecular weight existed in intact mature seed embryos and disappeared when the seeds were germinating. (4) Moreover, the electrophoretic patterns of total soluble proteins from callus being cultured with ABA, and from callus with regenerating plantlets, were very similar to those of total soluble proteins from mature seed embryos and germinating seed embryos in SDS polyacrylamide gel plates. (5) The practice that the callus precultured with addition of ABA, especially 10 mgL-1 ABA, followed by transferring to a regeneration medium gave us a high frequency of plantlet regeneration observed in the long-term culture of callus.View full abstractDownload PDF (764K) -
Hiroyuki DAIMON, Satoshi TAKADA, Masamichi OHE, Hironori MIMOTO1995 Volume 64 Issue 1 Pages 115-120
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSThe interspecific differences in germination, root nodule formation, dry matter production and nitrogen uptake were evaluated among Crotalaria species for the introduction as new green manure legumes. The germination progressed smoothly in C juncea and C spectabilis, but physical scarification was neccessary in C. pallida. In the field experiment, C. juncea had a high dry weight and a great nitrogen content at the early growing stage, but a drastic defoliation and a high C-N ratio were found at the late growing stage. C. pallida grew slowly at the early stage, but a high nitrogen content and an adequate C-N ratio for decomposition were found at the late growing stage. C. spectablilis showed intermediate traits in dry matter production and nitrogen uptake. In the root-box experiment, the distribution patterns of root systems and root nodules varied among the three species. C. juncea had greater root growth and nodulation compared with two other species at 35 days after sowing. When the three species are introduced to various cropping systems, these traits should be considered for choice as green manures.View full abstractDownload PDF (652K) -
Ebiamadon Andi BRISISE, Daisuke NISHIOKA, Hiroshi MIYAKE, Takeshi TANI ...1995 Volume 64 Issue 1 Pages 121-130
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSSemithin and ultrathin sections of callus tissues of African rice (Oryza glaberrima Steud) after 7 and 14 days of initiation were compared with similar cultures after 3, 5, 7 and 10 days of incubation on a differentiation medium. Histological examinations indicated that at the early stages of development, both types of callus tissue appear structurally similar with small, almost isodiametric and meristematic cells located toward the callus periphery. In addition to this cell type, cultures on a differentiation medium also contained large parenchymatous and highly vacuolate non-differentiating cells. Ultrastructurally, while the former were characterized by a relatively large number of organelles, the non-differentiating cells contained only a thin peripheral layer of cytoplasm. Later in culture, the differentiating cells undergo periclinal divisions resulting in the formation of radial files of tussue which correspond to the meristematic regions where shoot primordia differentiation is generally initiated. There is also evidence to show that the differentiation of shoot and/or root primordia in callus tissues is a high energy demanding process. This energy requirement is fulfilled by the accumulation, mobilization and utilization of starch and other reserve substances prior to the onset of plantlet regeneration.View full abstractDownload PDF (2610K) -
Ultrastructural Changes of Chloroplasts in Peanut Mesophyll Protoplasts Treated with Electric FieldsNisyawati, Hiroshi MIYAKE, Takeshi TANIGUCHI1995 Volume 64 Issue 1 Pages 131-138
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSUltrastructural changes in chloroplasts of peanut (Arachis hypogaea L. var. Lokal) seedling mesophyll cells and mesophyll protoplasts treated with electric fields were investigated. Generally, chloroplast profiles in mesophyll cells were biconvex, whereas those in mesophyll protoplasts were oval and round and some were divided. When the protoplasts were treated with electric fields, some chloroplasts were paired. Some of these seemed to result from division and others from fusion. This electric field treatment may stimulate chloroplast division and fusion, related to the activation of protoplasts which has been known to occur by the same treatment. There are two types of division, i.e. partition and fission. The division by partition was usually observed by invagination of the inner membrane of the chloroplast envelope. The fission type of division was recognized by a dumbbell-shaped profile and electron dense material was usually observed in the neck region. Some chloroplast profiles seemed to be produced by fusion of two chloroplasts, because the two parts had a common envelope and two thylakoid systems at the fusion area were disharmonious.View full abstractDownload PDF (2425K) -
Hiroshi SUGE, Takeaki NISHIZAWA1995 Volume 64 Issue 1 Pages 139-143
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSEthylene inhibited the growth of sorghum coleoptile and mesocotyl in darkness. It also inhibited the development of mesocotylar roots in darkness. However, ethylene rather stimulated the growth of mesocotyl under red light in a certain range of concentrations, 0.1-10 ppm, although it inhibited the growth of coleoptile and first leaf under the same condition. The optimum concentration of ethylene for mesocotyl growth under the light was different depending on the type of sorghum variety. Ethylene also induced the radial expansion of mesocotyl, especially at concentrations higher than 100 ppm under red light. The volume of mesocotyl increased in all ethylene concentrations tested. Development of mesocotylar roots was rather stimulated by ethylene under red light. Carbon dioxide acted antagonistically with ethylene in the growth of mesocotyl and coleoptile in darkness. Thus, sorghum mesocotyl is a unique organ in which ethylene stimulates not only longitudinal growth but also radial expansion.View full abstractDownload PDF (649K) -
Saneaki TANAKA, Akira YAMAUCHI, Yasuhiro KONO1995 Volume 64 Issue 1 Pages 144-147
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSConvenient methods for root length measurement are highly demanding. In this report we demonstrated an easily accessible method of image analysis for this purpose consisting of a personal computer, a commercially-available image scanner, a public domain image analysis and processing software (NIH Image). Its performance, together with that of the root length scanner, was evaluated by way of a comparison with the directly-measured root length for soybean, maize and rice, all of which differ in root diameter and rooting density of lateral roots. Preliminary trials for the measurement of nylon threads and stainless wires with known length validated the accuracy of this method for the expected range of root diameters. This method measured length precisely for maize and soybean, while the root length scanner read 81% of the actual length for maize and 89% for soybean. For rice, the root system of which consisted very fine roots, the image analysis method gave an underestimation of about 7.5%, probably due to the fact that overlapping and clumping of thin lateral roots was unavoidable during the root sample preparation for image analysis. By contrast, the root length scanner measured only one fourth of the actual length. This method also saved time required for measurement from one-fourth to one-fifth compared with direct measurement.View full abstractDownload PDF (548K) -
Saneaki TANAKA, Akira YAMAUCHI, Yasuhiro KONO1995 Volume 64 Issue 1 Pages 148-155
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSA crop root system morphology can be determined by the development of different component roots, such as nodal root axes and their concomitant lateral roots of two different types ; long, large in diameter, and branching (L type), and short, small in diameter, and non-branching (S type). In this respect, we attempted to examine the cultivar difference in root system morphology among rice cultivars and to evaluate phenotypic plasticity in the root system morphology when grown under different nitrogen (N) application regimes. Four rice cultivars that are known to differ in adaptability for heavy manuring (AHM) and ecotype (indica and japonica) were grown for 14 days under three N levels. Cultivar difference in root system morphology existed among the four cultivars. The differences were recognized in the ratio of lateral roots to the entire root system length, and more remarkably in the ratio of S type to L type lateral root number. The difference in the former parameter could be well related to that in the ecotype, while the latter to the AHM of the cultivar. As to the phenotypic plasticity, the three component roots differed in production response, while they were fairly similar in elongation response. The root system morphology of a cultivar with low AHM was considerably phenotypically plastic, while that of the other cultivars were relatively stable to the changes of N conditions in soil.View full abstractDownload PDF (759K) -
Yoshio INOUE, Shinsuke MORINAGA1995 Volume 64 Issue 1 Pages 156-158
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (405K) -
[in Japanese], [in Japanese], [in Japanese]1995 Volume 64 Issue 1 Pages 159-165
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (779K) -
[in Japanese]1995 Volume 64 Issue 1 Pages 166-171
Published: March 05, 1995
Released on J-STAGE: February 14, 2008
JOURNAL FREE ACCESSDownload PDF (726K)
- |<
- <
- 1
- >
- >|