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591.
Toshio Akagi Shigeru Mitani Keiichiro Ito Itaru Shigehara Terumasa Komyoji Norifusa Matsuo 《Pest management science》1995,44(1):39-48
A series of pyridylcarbamates showed high potency against cucumber gray mould (Botrytis cinerea Pers.). The most potent compound, propargyl-N-(6-ethyl-5-iodo-2-pyridyl)carbamate was effective against an isolate sensitive to benzimidazole and dicarboximide fungicides as well as against an isolate resistant to both types of compound. QSAR analyses and molecular modelling studies were carried out to investigate the structural requirements for highly active compounds and the structural feature of the binding site of each strain. Significantly different QSAR equations were obtained only for substituents at the 6-position of the pyridine ring. An ethyl-sized pocket or an ethyl terminal recognition was suggested in the case of the sensitive or resistant isolate respectively. These results could explain the phenomenon of negatively correlated cross-resistance between benzimidazoles and N-phenylcarbamate fungicides. Substituent effects at the 5- or 2-position were governed by steric factors. Substituent effects at the 3-position were explained by steric hindrance or by conformational effects. The propargyl-substituted compound above was the most desirable one from the viewpoint of QSAR. 相似文献
592.
593.
Erika SATO Yu Y. MIN Koki TOYOTA Atsushi TAKADA 《Soil Science and Plant Nutrition》2009,55(4):478-484
A preliminary survey using 20 conventionally farmed fields in which fumigants have been applied every year showed that the root-lesion nematode Pratylenchus penetrans was distributed both in the upper (0–30 cm) and lower (30–60 cm) soil layers. In six of the 20 fields, P. penetrans was detected in the lower layers exclusively, suggesting that the most appropriate depth to sample soil is 0–60 cm to estimate the relationship between the density of P. penetrans and its damage to radish. There was a highly significant correlation ( r = 0.923) between the density of P. penetrans in the 0–60 cm depth and the number of spots on a radish. No damage to radish was observed in soils with <2.5 individuals of P. penetrans per 20 g soil before cultivation. However, in cases in which the density of P. penetrans was 3.4–6.2 individuals per 20 g soil, the number of spots on a radish showed more variation (0–131.5 per radish) and there was no significant correlation between them. The nematode community structure of soils with 3.4–8 individuals of P. penetrans per 20 g soil, evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis, was significantly different ( anova , PC2, P < 0.05) between soils with low (0–42) and high (more than 80) damage levels, suggesting that radish damage might be predicted on the basis of the prevailing soil nematode community structure. 相似文献
594.
595.
Shunsuke Yamamoto Yoshitaka Tanetani Chihiro Uchiyama Atsushi Nagamatsu Masami Kobayashi Mitsumasa Ikeda Kiyoshi Kawai 《Journal of Pesticide Science》2021,46(3):249
Fenquinotrione is a novel herbicide that can control a wide range of broadleaf and sedge weeds with excellent rice selectivity. We revealed that fenquinotrione potently inhibited the 4-hydroxyphenylpyruvate dioxygenase (HPPD) activity in Arabidopsis thaliana with an IC50 of 44.7 nM. The docking study suggested that the 1,3-diketone moiety of fenquinotrione formed a bidentate interaction with Fe(II) at the active site. Furthermore, π–π stacking interactions occurred between the oxoquinoxaline ring and the conserved Phe409 and Phe452 rings, indicating that fenquinotrione competes with the substrate, similar to existing HPPD inhibitors. A more than 16-fold difference in the herbicidal activity of fenquinotrione in rice and the sedge, Schoenoplectus juncoides, was observed. However, fenquinotrione showed high inhibitory activity against rice HPPD. Comparative metabolism study suggested that the potent demethylating metabolism followed by glucose conjugation in rice was responsible for the selectivity of fenquinotrione. 相似文献
596.
Satoshi Kono Tassanee Ounvichit Atsushi Ishii Masayoshi Satoh 《Paddy and Water Environment》2012,10(1):75-81
In principle, participatory irrigation management (PIM) means the involvement of irrigation users in all aspects at all levels
of irrigation management. In practice, all over the world efforts are being made to realize the principles. However, in the
execution of PIM, role sharing between farmers and government is a serious problem, and thus a clear method and ideas are
needed to improve PIM. In particular, a broad discussion of role sharing is demanded. This article illustrates how the Japanese
way of role sharing in PIM is realized based on the case of the Toyogawa Irrigation Project. Organizationally, the project
is jointly managed by five entities, including both the public sector and the farmers’ organizations. These entities have
clearly divided their functional roles, with the ultimate decision power in all aspects of irrigation management given to
organized farmers. The power is realized either directly or through the land improvement districts’ representative system
depending on the levels of the irrigation system. The public entity provides coordination support to create a transparent
forum of discussion together with scientific information for farmers’ understanding and decision making. The participatory
institutional line-up of this project enables the upland areas that suffered periodically from water deficits. 相似文献
597.
598.
Akira?KawakamiEmail author Naoki?Kato Takahide?Sasaya Keisuke?Tomioka Hiroyoshi?Inoue Atsushi?Miyasaka Kazuyuki?Hirayae 《Journal of General Plant Pathology》2015,81(4):324-327
Ear rot with white or pink mold was found on corn (Zea mays L.). A species of Fusarium, not registered previously as a pathogen causing Gibberella ear rot of corn in Japan, was isolated from the rotted ear. The isolates, identified as F. asiaticum based on morphological characteristics and nucleotide sequences, caused white or pink mold on corn ear after inoculation. Moreover, the 3-acetyl deoxynivalenol chemotype and the nivalenol chemotype were found in the isolates. We propose to include F. asiaticum as one of the pathogens causing Gibberella ear rot of corn in Japan. 相似文献
599.
Masanori Takahashi Michio Yoneda Hajime Kitano Atsushi Kawabata Mami Saito 《Fisheries Science》2014,80(2):293-300
The growth of juvenile chub mackerel Scomber japonicus collected in the western North Pacific Ocean in 2007 and 2009 was examined based on the evidence of otolith daily increment formation in captive specimens. There was a significant difference in the relationship between known age and number of increments in the frontal and sagittal planes. Repeated markings on the otolith using Alizarin complexone and the coefficient of variation in number of increments suggest that the increments in the frontal plane of the otolith are more suitable for age estimation than those in the long and short axes of the sagittal plane. The increments in the frontal plane formed daily, and the first ring was usually deposited 3 days after hatch. Age of wild juveniles ranged from 24 to 211 days after hatch based on the frontal plane method. The estimated hatching periods of specimens ranged from February to June, but the April-hatched specimens were collected throughout the sampling periods of 2007 and 2009. The Gompertz growth model showed a difference in growth pattern in specimens between 2007 and 2009. The juveniles in 2009 appeared to grow more quickly than those in 2007 until summer, but thereafter the 2009 specimens seemed to grow more slowly. 相似文献
600.
Shiga A Ota Y Ueda Y Hosoi M Miyajima R Hasegawa K Mizuhashi F 《Journal of toxicologic pathology》2010,23(4):253-260
Focal granulomatous inflammation developed in the livers of five 10-week-old male Sprague-Dawley rats. The characteristic features of this lesion were the presence of foreign body multinucleated giant cells engulfing calcium deposits and site-specific development in a fissure formed in a sub-lobation in the left lobe or interlobar fissure of the medial lobe of the liver. To clarify the pathogenesis of this lesion, rat livers showing abnormal sub-lobation or lobar atrophy, rat livers in an acute dermal toxicity study and guinea pig livers in a skin sensitization test were also examined histologically. Consequently, the present lesion was considered to be a reactive change against calcium that was dystrophically deposited in the area of hepatocellular necrosis due to delayed circulatory disturbance caused by external pressure or extension force. Granulomatous lesions like in the present cases should be differentiated from those caused by evident exogenous pathogens such as chemicals or microorganisms. 相似文献