Japan Agricultural Research Quarterly: JARQ
Online ISSN : 2185-8896
Print ISSN : 0021-3551
ISSN-L : 0021-3551
42 巻, 3 号
選択された号の論文の13件中1~13を表示しています
REVIEWS
Crop Science/Horticulture
  • Takashi ONOZAKI
    原稿種別: REVIEW
    2008 年 42 巻 3 号 p. 137-144
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    The vase life of cut flowers, or flower longevity, is one of the most important characteristics that determine their quality and their ability to satisfy consumer preferences. To improve the vase life of carnations, conventional cross-breeding techniques were used to develop many carnation lines with a long vase life. Two new cultivars, ‘Miracle Rouge’ and ‘Miracle Symphony’, with a genetically determined long vase life, were developed. They had vase lives of 17.7 to 20.7 days (3.2 to 3.6 times the vase length of the ‘White Sim’ cultivar) under standard conditions (23°C, 12-h photoperiod, 70% RH). The ethylene biosynthesis pathway in these cultivars was almost completely blocked during natural senescence, which was responsible for the long vase life. Changes in ethylene sensitivity with flower senescence were evaluated using a time-lapse video recording system, which provides a simple and accurate way of evaluating ethylene sensitivity. The video system revealed that the ethylene sensitivity of various cultivars including ‘Miracle Rouge’ and ‘Miracle Symphony’ after anthesis decreased with increasing age.
Agricultural Economics
  • Kazuo ANDO, Haruo UCHIDA, Habibur RAHMAN, S.M. Altaf HOSSAIN
    原稿種別: REVIEW
    2008 年 42 巻 3 号 p. 145-150
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    A village committee was established to look after rural development activities that were initiated by joint efforts of villagers and staff members of the Joint Study on Rural Development Experiment (JSRDE) project team sponsored by JICA in Bangladesh. The committee was formed of the so-called traditional village leaders, or matabbors, some of whom proved to be active in enhancing villagers′ unity and devotion to village public affairs. At the same time, a village coordination meeting of local government officers was formed to coordinate the activities of the government concerning rural development. The Thana (local administrative office) officer played pivotal roles in organizing the meeting. An effort was made to “link” the organizations of local governments and the village committee, so that the governments′ rural development services were channeled into the village through a public, formal “door” of the village. Various trials implemented in the village indicated that successful linkage hinges upon the single facet of “openness” or “transparency” in information dissemination, which had been rather lacking in rural Bangladesh. The important processes of formulating the village committee and the village coordination meeting of local governments and clues for successful communication and dissemination of related information are documented in this paper. Moreover, analysis of an economic aspect of rural infrastructure reveals that bridge construction in the village was efficient in generating income for the poor.
ARTICLES
Biotechnology
  • Tomoko TAKAMIYA, Yuhko OHTAKE, Saeko HOSOBUCHI, Tomotsugu NOGUCHI, Mak ...
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 151-155
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Tissue culture is used as a tool to propagate seedlings massively in industry. However, unfavorable genomic alteration that affects phenotypic characters occurs in the procedure. A technique which scans these genetic changes genome-wide can enables us to discriminate the clone that has genomic alteration at early stages. In this study, we used restriction landmark genome scanning (RLGS) to detect alterations among ramets of rice, which redifferentiated from a callus that had been cultured for 4 weeks. As a result, 6% (10 spots) of the total (161 spots examined) were different between two ramets. One spot out of ten was cloned and was located on a predicted gene. Application of a PCR-based method to the RLGS spot region detected one methylation alteration among the ramets. Accordingly, RLGS was successful in surveying methylation alteration events during tissue culture in plants and it should be possible to use this method for monitoring of alteration levels.
Crop Science
  • Yukiko JOHO, Kenji OMASA, Naoyoshi KAWANO, Jun-Ichi SAKAGAMI
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 157-162
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    In inundation areas in rainfed lowland and inland valleys of Guinea as well as other regions in Africa, submergence for a few days to a few weeks with a water depth less than 50 cm occurs in rice cultivation during the rainy season. Young rice seedlings after transplanting are particularly vulnerable to submergence stress. Oryza glaberrima Steud. is well adapted to growth in inundation areas with deepwater conditions in West Africa; however, it is not evident whether it resists short-term submergence stress after transplanting. The purpose of the study was to understand the physiological responses of rice plants after transplanting to short-term submergence stress under rainfed conditions for O. glaberrima by comparison with several genotypes of Oryza sativa L. from Guinea. Eight genotypes of O. glaberrima and seven genotypes of O. sativa including two shoot elongation genotypes, one submergence tolerant genotype as a control cultivars, and four genotypes of common cultivars in West Africa were used. Thirty day-old seedlings were submerged completely for 10 days with medium deepwater conditions at 45 cm water depth at 13 days after transplanting in a lowland field. O. glaberrima showed higher shoot elongation ability during submergence than any genotype of O. sativa that we tested. However, O. glaberrima lodged easily after desubmergence due to longer and rapid shoot elongation during submergence, and thus triggered a decrease in its survival rate. The submergence tolerant genotype of O. sativa maintained the dry matter weight of the leaf blade during submergence through the inhibition of shoot elongation. We suggest that O. glaberrima is susceptible to short-term submergence while it may adapt to prolonged flooding because of improved restoration of aerial photosynthesis and survival rate through shoot elongation ability.
Agricultural Environment
  • Yoko NAKAGAWA, Chin YAN, Takahiro SHIONO, Teruhito MIYAMOTO, Koji KAME ...
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 163-172
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    The validities of the DeNitrification-DeComposition (DNDC) model and the simulation parameters were examined by using the experimental data obtained at Miyako Branch of Okinawa Prefectural Agricultural Research Center. The obtained simulation results were compared with the observed values and it was concluded that the simulation with the measured parameters could produce better simulation results than the simulation with the model provided default parameters. The model seemed to be able to predict the total amounts of leached water and nitrate and N2O emissions reasonably well, but the modifications in the model seemed to be still needed for capturing precise seasonal leaching and emission patterns. The sensitivity of the model was analyzed by either increasing or decreasing one of the crop and soil parameters by 25% while holding all other parameters and inputs constant. The changes in water filled porosity at field capacity were found to have the largest effects on the amount of leached water and N2O emissions. The amount of leached nitrate was affected by the changes in water filled porosity at field capacity only slightly, but it was reduced significantly by an increase in soil pH.
  • Takao TSUKIBOSHI, Keiichi TAKAHASHI, Ryuichi UEGAKI, Koya SUGAWARA
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 173-179
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    The causal fungus of black choke disease in various C4 warm season grasses was collected from places mainly in Ishigaki Island, the most southern region of Japan. The fungus was found on 19 species of 14 genera of C4-grasses such as Brachiaria, Chloris, Chrysopogon, Cynodon, Digitaria, Echinochloa, Eragrostis, Eriochloa, Imperata, Leptochloa, Miscanthus, Panicum, Paspalum, and Pennisetum, including turfgrasses and forage crops. The fungus colonizes flowering heads and makes them mummified in appearance with the panicles attaching to each other. The color of the mature stromata ranges from grayish-white to black. Leaf surfaces of some grasses are colonized by the fungus, producing white streaks of hyphae. Many colorless, needle-shaped conidia of 10-25 × 0.5-1 μm are produced on infected tissues. The fungus was identified as Ephelis japonica based on the morphologies and molecular characteristics. Epiphytic features of E. japonica were examined using infected and uninfected Paspalum thunbergii clones from which the fungus was eradicated by treatment with a systemic fungicide. Hyphae colonized the surface of leaf primordia only in infected plants, a feature shared with some of the closely related Balansia spp. The potential for utilizing E. japonica to confer insect and disease resistance in turfs and forage crops was discussed.
  • Tadashi ISHII, Toshiro MATSUNAGA
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 181-186
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Rice (Oryza sativa) seedlings were grown in the presence of 5 mM orthosilicic acid (H4SiO4, IUPAC name: tetrahydroxyl silane). More than 80% of silicon absorbed in the rice was localized in the alcoholinsoluble residues (AIR) fractions. AIR refers to cell wall materials in the text. Driselase (commercial cell wall hydrolyzing enzyme preparation) released 3% of silicon present in the rice AIR into water-soluble fractions. Size-exclusion high performance liquid chromatography/inductively coupled plasma atomic emission spectroscopy (HPLC/ICP-AES) showed that an aqueous silicon-containing substance with high molecular weight was present in the water-soluble fractions. The compounds were stable at pH 6.5, while commercial silica sols which were stable at pH 9.0 were insoluble at the neutral pH. The stability in neutral pH may be due to the presence of a complex of polysaccharide and protein in the molecule. These results imply that silica-containing macromolecules exist in rice cell walls.
  • Takuhito NOZOE, Ruth AGBISIT, Yoshimichi FUKUTA, Reynaldo RODRIGUEZ, S ...
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 187-192
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    In the 2003 wet season, IR64 (check variety) and four lines of rice (Oryza sativa L.) developed at IRRI were cultivated in a field with iron (Fe) toxicity at Iloilo City, Philippines, and also under normal soil conditions at IRRI farm. Two of the lines used in the experiments were the near isogenic lines (NILs) of IR64, selected as Fe-tolerant lines in solution culture in the greenhouse. The other two lines were elite breeding lines that were selected as Fe-tolerant lines in the field trial at Iloilo. The tolerances of NILs were not expressed at the Iloilo field site because the yield reductions due to Fe-toxicity were similar to or larger than those for IR64. The yield reduction of elite breeding lines was smaller than that of IR64, indicating that the tolerance of elite breeding lines was expressed at the Iloilo field. At Iloilo, the shoot dry weights of IR64 and its NILs hardly increased after 73 days of cultivation. On the contrary, those of elite breeding lines kept on increasing. While the root dry weight of IR64 and its NILs decreased abruptly after 50 days of growth, those of elite breeding lines remained constant or decreased gradually. This finding suggests that one of the factors that suppressed the growth of IR64 and its NILs during the late stage was early root senescence. Since the tolerance of elite breeding lines was associated with the maintenance of root activity during the late stage of growth, the long maturity period of elite breeding lines presumably helped to alleviate the toxicity.
Agricultural Engineering
  • Chattichai WAISURASINGHA, Masamu ANIYA, Akira HIRANO, Janya SANG-ARUN, ...
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 193-201
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Rice is annually destroyed by seasonal flooding in South and Southeast Asia. In order to reduce the loss of rice production, an accurate assessment of flood-affected paddies is essential. Taking the 2001 monsoon flooding that hit the Lower Chi River Basin, northeastern Thailand, as a case study, we derived the flood depth over the large and inaccessible areas using a RADARSAT-1 image acquired during the flooding peak and a 30-m Digital Elevation Model. Based on the elongation properties of rice, we used the critical water-depth of 80 cm to classify the flood-affected paddies into ‘damaged’ or ‘non-damaged’ paddies. Our results show that only about 40% of the flood-affected paddies were actually damaged paddies. In addition, we analyzed the damaged paddies by overlaying the derived water depth with the flood frequency map in order to recommend planting the appropriate rice varieties. Our analysis reveals that remote sensing and GIS can be used to minimize the loss of rice production and thus help farmers to increase their income in the long run, which will save the government money paid in flood compensations.
  • Koji KITAMURA
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 203-210
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Water users associations (WUAs) are expected to play an important role in operation and maintenance (O&M) of the irrigation and drainage infrastructure in Central Asia. The roles and issues facing WUAs in the Kyrgyz Republic and Uzbekistan are reviewed and analyzed in this study. It is identified that continuous financial stability of WUAs after the completion of donors′ irrigation projects is crucial for appropriate O&M. Especially, the estimated calculation of the cost recovery, irrigation service fees (ISF) and O&M costs are optimistic rather than realistic cases as these have been determined politically and are based on several assumptions. They should be determined based on economic and financial analysis, taking into account farmers′ ability to pay. Collection rates of the cost recovery and ISF should also be improved.
Food Technology
  • Shigeru OITA, Toshiyuki KIMURA, Yukinori SHIBUYA, Naoto NIHEI, Kon TAN ...
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 211-214
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Proteins of Perilla frutescens seeds were step-extracted with 20 mmol/L phosphate buffer, 0.5 mol/L NaCl, 70% ethanol, and 3% acetic acid. The total amount of extracted proteins from 1 g of seeds was 138.6 mg and 96.7% of the amount of proteins was water- and NaCl-soluble. The water- and NaCl-soluble perilla proteins contained large amounts of Glu, Gly, Asp, Val, and Arg, but lower amounts of Met and His. The water- and NaCl-soluble perilla proteins were immediately digested in simulated gastric fluid containing pepsin. The water-soluble perilla proteins had less trypsin-inhibitive activity compared with soybean and the NaCl-soluble perilla protein had no trypsin- inhibitive activity.
Animal Husbandry
  • Yuko KAMIYA, Mitsuru KAMIYA, Masahito TANAKA, Shigeru SHIOYA, Ikuo HAT ...
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 215-221
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Whole crop rice silage (WCRS) has recently attracted attention as forage for dairy cows. The nutritive value of WCRS (Forage rice cultivar: Nishiaoba) was examined by a balance trial (Experiment 1). The forage rice was harvested and ensiled in two ways (round-baled silage and container silage). On a dry basis, the contents of metabolizable energy, crude protein and neutral detergent fiber in WCRS were 1.7 Mcal/kg, 6.3% and 47.4%, respectively in round-baled silage, and 2.0 Mcal/kg, 7.4% and 46.6%, respectively in container silage. The feed value of Nishiaoba WCRS for lactating dairy cows under high ambient temperature was also investigated (Experiment 2). The daily milk yields of cows fed WCRS as part of their total mixed ration (rice TMR) and oats hay as part of their TMR (oats TMR) were 29.7 and 30.1 kg, respectively. The dry matter intakes (DMI) of cows when fed the rice TMR and oats TMR were 18.5 and 19.7 kg, respectively. There were no significant differences in DMI, milk yield and composition between cows fed the rice TMR and the oats TMR. The energy retention of the cows fed the rice TMR was significantly lower than that of the cows fed the oats TMR (P < 0.05). WCRS can be given, with other adequate roughages and concentrates, to dairy cows that produce 30 kg of milk daily, even under high ambient temperature.
  • Koji NAKAGAMI, Seiichi SAKANOUE, Shigeo TAKAHASHI
    原稿種別: ARTICLE
    2008 年 42 巻 3 号 p. 223-229
    発行日: 2008年
    公開日: 2013/03/26
    ジャーナル フリー
    Zoysia japonica Steud. is unique among Japanese native grasses due to its adaptation for grazing and has been re-evaluated by smallholders of beef calf production in Japan, because of its sustainability without any fertilizer. The relationship between stocking density and herbage production is a key factor for the sustainable management of grazing pastures. Moreover, net primary productivity including both above- and below-ground parts is a parameter used to quantify the net carbon absorption rate by living plants. Generally, stocking density levels affect plant production of pastures. Therefore, to determine the impact of defoliation intensity on net primary productivity of a Z. japonica-dominated pasture, the plant mass including below-ground parts was determined for three years under the stocking densities averaging 3.9, 2.7 and 1.6 animal units ha-1 y-1 at the start of the grazing season under set-grazing of beef cattle from June to September. The net primary productivity ranged from 291 to 421 g DM m-2 y-1 for above-ground (ANPP) and from -38 to 51 g DM m-2 y-1 for below-ground parts. The ANPP was found to be affected by defoliation intensity, defined as the ratio of ANPP that was grazed, and attained a maximum when the defoliation intensity was about 40%. As for cattle performance, they maintained their weight during the grazing season below 35% of annual defoliation intensity.
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