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1.
Rie Gappa-Adachi Yasuaki Morita Yoshifumi Shimomoto Shigeharu Takeuchi 《Journal of General Plant Pathology》2014,80(1):103-107
Sweet peppers (cv. Tosajishi beauty) with leaf blight symptoms were observed in Kochi Prefecture, 2003. Initially, small spots formed on leaves, and later enlarged to brown to dark brown spots, and eventually blighted leaves fell. Several bacteria that caused the same symptoms were isolated and subsequently reisolated. These bacteria were identified as Pseudomonas cichorii on the basis of bacterial characteristics and the 16S rRNA gene sequence. This is the first report of bacterial leaf blight in the sweet pepper in the world. 相似文献
2.
Yutaka Watanabe 《Soil Science and Plant Nutrition》2013,59(3):33-36
The many important physical and chemical reactions which occur in soils are ascribed to the clay fraction of soils. Therefore, soil physics and soil chemistry are truly based on the colloidal phenomena of soil clays. 相似文献
3.
Sato D Awad AA Chae SH Yokota T Sugimoto Y Takeuchi Y Yoneyama K 《Journal of agricultural and food chemistry》2003,51(5):1162-1168
A simple and rapid analytical method for strigolactones, germination stimulants for the root parasitic weeds witchweed (Striga spp.) and broomrape (Orobanche spp.), has been developed using high-performance liquid chromatography connected to tandem mass spectrometry (LC/MS/MS). The natural strigolactones (strigol, sorgolactone, orobanchol, and alectrol) were clearly separated and identified by LC/MS/MS. As low as 0.1 pg/microL of strigol and 0.5 pg/microL of sorgolactone could be quantified, whereas 1 pg/microL was needed for the quantification of orobanchol (S/N > 10). Using this method, it was found that red clover produces orobanchol and alectrol but not strigol. The roots of red clover seedlings were found to produce 13, 70, 58, and 65 pg of orobanchol/plant 1, 2, 3, and 4 weeks after germination, respectively. 相似文献
4.
Hoy-Taek Kim Yutaka Hirata Yong-Uk Shin Hae-Sung Hwang Jeong-Hwan Hwang Il-Sheob Shin Dae-Il Kim Sang-Jo Kang Hyun-Jung Kim Dong-Young Shin Ill-Sup Nou 《Euphytica》2004,138(1):73-80
The pear cultivar ‘Osa-Nijisseiki’ (S2Ssm
4; sm = stylar-part mutant) has been used as a parent to breed self-compatible cultivars that produce excellent fruits. However,
determination of the self-compatibility of ‘Osa-Nijisseiki’ offspring requires a lot of time, 6 years or more, by conventional
cross breeding. We have designed a rapid reliable method for the identification of self-compatible varieties of ‘Osa-Nijisseiki’
offspring based on the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) with S-allele specific
restriction endonucleases. By using this method, 8 self-compatible varieties were selected among 16 selections resulting from
a cross between the self-compatible cultivar ‘Osa-Nijisseiki’ (S2Ssm
4) and the self-incompatible cultivars ‘Niitaka’ (S3S9), ‘Whasan’ (S3S5), ‘Chuwhangbae’ (S4S6). The S-genotypes of 16 ‘Osa-Nijisseiki’ offsprings were also determined.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Excess cyclin E-Cdk2 accelerates entry into S phase of the cell cycle and promotes polyploidy, which may contribute to genomic instability in cancer cells. We identified 20 amino acids in cyclin E as a centrosomal localization signal (CLS) essential for both centrosomal targeting and promoting DNA synthesis. Expressed wild-type, but not mutant, CLS peptides localized on the centrosome, prevented endogenous cyclin E and cyclin A from localizing to the centrosome, and inhibited DNA synthesis. Ectopic cyclin E localized to the centrosome and accelerated S phase entry even with mutations that abolish Cdk2 binding, but not with a mutation in the CLS. These results suggest that cyclin E has a modular centrosomal-targeting domain essential for promoting S phase entry in a Cdk2-independent manner. 相似文献
6.
Analysis of return flows in a tank cascade system in Sri Lanka 总被引:2,自引:0,他引:2
Matsuno Yutaka Tasumi Masahiro van der Hoek Wim Sakthivadivel Ramaswamy Otsuki Kyoichi 《Paddy and Water Environment》2003,1(4):173-181
In Sri Lanka, irrigation reservoirs (tanks) are usually connected sequentially and form cascades along the landscape. A study was carried out in the Anuradhapura District in the dry zone of Sri Lanka to understand the role of return flows in such tank cascade systems. The water balance of a tank cascade system was estimated using hydrological data collected over a one-year period. The system was extended about 25 km along a river composed of three small reservoirs having the command area of 31, 55, and 55 ha, respectively. In this system, about 46% of seepage water from tanks entered the paddy fields of the command area. The crop consumed part of the water and the rest returned to the downstream tank through the drainage canals. Percolation loss in the command areas was low (3.6 mm/day) since a considerable portion of the percolation returned to the downstream tank. These results showed that return flows, which are generally disregarded in the water budget, contributed considerably to the water supply of the tank cascade system. 相似文献
7.
Sirusa Kritsanapuntu Nilnaj Chaitanawisuti Yutaka Natsukari 《Aquaculture International》2009,17(1):77-84
Growth and water quality for growing-out of juvenile spotted Babylon, Babylonia areolata, were determined at three water-exchange regimes of 7-, 15- and 30-day intervals in large-scale operation of earthen ponds
over a 5-month period. Results showed that growth was significantly different among the water-exchange treatments (P < 0.05). The higher body weight gains and shell length increments were observed in snails held at water exchange of 7- and
15-day intervals when compared with those held at water exchange of 30-day intervals. At the end of the experiment, average
body weight gains were 4.22, 3.73 and 2.77 g for snails held in water-exchange treatments of 7-, 15- and 30-day intervals,
respectively, and 16.63, 15.04 and 13.78 mm for those of shell length increments, respectively, The average final survivals
were 83.60, 80.90 and 74.20% for snails held in water-exchange treatments of 7-, 15- and 30-day intervals, respectively. Seawater
temperature, salinity, pH, dissolved oxygen, nitrite–nitrogen and ammonia–nitrogen had gradually changed throughout the culture
period for all water-exchange treatments. With one exception, the total alkalinity showed the greatest changes during the
culture period for all water-exchange treatments ranging from 58.67–97.50 mg/l. 相似文献
8.
Yoshimasa Sugiura Yoshirou Takeuchi Makoto Kakinuma Hideomi Amano 《Fisheries Science》2006,72(6):1286-1291
ABSTRACT: The effects of 80% methanol extracts from frozen samples of 41 macroalgae and one sea grass collected in the Ise-Shima region of Japan were investigated on histamine release from rat basophile leukemia cells (RBL-2H3) sensitized with antidinitrophenyl (DNP) IgE and stimulated with DNP-BSA. Of the 21 brown algae, five green and 15 red algae, and one sea grass tested, only extracts from seven brown algae suppressed histamine release from RBL cells, as determined by high-performance liquid chromatography (HPLC) analysis. When the cytotoxic effects of the seven brown algal extracts were investigated by Trypan blue staining, only Eisenia arborea and Sargassum thunbergii did not show cytotoxic effects. Therefore, we conclude that E. arborea and S. thunbergii may contain compounds that have antiallergic effects without inducing cell death. 相似文献
9.
Two 21 day experiments were conducted to determine whether microparticulate diets could be used to substitute for diatoms for raising (Experiment 1) as well as settling and on‐growing (Experiment 2) Haliotis diversicolor supertexta postlarvae. The experiments were conducted in 10 L flow‐through tanks and each diet had three replicate tanks. In experiment 1, three experimental microparticulate diets supplied by a commercial feed company, labelled SF‐15, SF‐15 (T) and JFY‐13–1, were used, and in experiment 2, SF‐15 and SF‐15 (T). Artificial diets were compared to diatoms in terms of supporting growth and survival. The survival rate for experiment 1 was lowest for JFY‐13–1 (0%) and highest for diatoms (12.9±0.8%). The final size of postlarvae fed SF‐15 and SF‐15 (T) was significantly greater than that of postlarvae fed diatoms, 973±193 μm and 996±220 μm compared to 786±141 μm. In experiment 2, a total number of 501 larvae settled onto plates covered with SF‐15, 254 on SF‐15 (T) and 1085 on diatoms. The highest survival rate was 33.1±6.9% for SF‐15 and the lowest was 17.3±5.0% for diatoms. However, the final length of postlarvae fed diatoms was significantly greater than SF‐15 and SF‐15 (T); 1018±379 μm compared to 728±89 μm and 717±90 μm. The artificial micro diets used in this study were comparable to diatoms in terms of grow and survival of postlarval H. diversicolor supertexta. 相似文献
10.
Makoto Kiguchi Yutaka Kataoka Hiroshi Matsunaga Koichi Yamamoto Philip D. Evans 《Journal of Wood Science》2007,53(3):234-238
The market for wood-fiber plastic composites (WPCs) is expanding rapidly in many countries including Japan, where WPCs are
mainly used for exterior products. In such applications, WPCs undergo undesirable color change, chalking, and shrinkage and
swelling, and accordingly there is a need to better understand the mechanisms responsible for the weathering of WPC and develop
methods of improving their weathering resistance. In this study, weatherability of WPC was assessed by natural and accelerated
weathering trials. Discoloration (whitening) of WPC during exposure was caused by degradation of both wood and plastic. Darker
color pigments as additives improved the color stability of WPC; however, chalking on the surfaces still occurred. The color
stability of WPC was improved by application of exterior coatings. Preweathering of WPC (before coatings were applied) increased
the absorption of coatings by the WPC and had a positive effect on the color stability and prevented chalking of the composites.
Parts of this study were presented at the IUFRO XXII World Congress Meeting, Brisbane, August 2005 and the IAWPS 2005, Yokohama,
November 2005 相似文献