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81.
The discovery of dinotefuran: a novel neonicotinoid   总被引:1,自引:0,他引:1  
Dinotefuran (MTI-446: (RS)-1-methyl-2-nitro-3-(tetrahydro-3-furylmethyl)guanidine) is a new neonicotinoid commercialized by Mitsui Chemicals. Research led to this novel neonicotinoid by the removal of the chloropyridine or chlorothiazole ring that had been considered as indispensable for neonicotinoides. The research advanced as follows; (1) selection of acetylcholine for the lead compound, (2) recognition of the insecticidal advantages of 3-methoxypropyl compounds, (3) synthesis of (+/-)-tetrahydro-3-furylmethyl compounds by cyclization of the 3-methoxypropyl moiety. It resulted in dinotefuran which has a (+/-)-tetrahydro-3-furylmethyl moiety instead of a halogenated aromatic heterocyclic ring, and belongs to the third-generation neonicotinoids (sub-class: furanicotinyl compounds).  相似文献   
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83.
Citrus psorosis virus (CPsV) was detected from citrus trees for the first time in Japan. The diagnosis was confirmed by molecular, serological, and biological indexing. RT-PCR detected CPsV from two citrus trees among ca. 200 tested. Both trees were variety Shiranui of [Citrus unshiu Marc. × C. sinensis (L.) Osb.] × C. reticulata Blanco, and neither had the bark scaling symptom typical of CPsV. The CPsV isolate could be genetically related to those from Spain, Italy, Florida, and California.  相似文献   
84.
The causal agent of apple mosaic disease has been previously thought to be solely caused by apple mosaic virus (ApMV). In this study, we report that a novel ilarvirus is also associated with apple mosaic disease. Next-generation sequencing analysis of an apple tree showing mosaic symptoms revealed that the tree was infected with three apple latent viruses (apple stem pitting virus, apple stem grooving virus, and apple chlorotic leaf spot virus) and a novel ilarvirus (given the name apple necrotic mosaic virus (ApNMV)) that is closely related to Prunus necrotic ringspot virus (PNRSV) and ApMV. The genome of ApNMV consists of RNA1 (3378 nt), RNA2 (2767 nt), and RNA3 (1956 nt). A phylogenetic analysis based on the coat protein amino acid sequences indicated that the novel virus belongs to the same subgroup 3 of the genus Ilarvirus as PNRSV and ApMV. The presence of mosaic leaves, which tend to be unevenly distributed in diseased apple trees, was correlated with the internal distribution of ApNMV. RT-PCR detection of mosaic-diseased apple trees in Japan indicated that ApNMV was detected in apple trees introduced from China, whereas ApMV was detected from cultivated apple trees in domestic orchards. Consistent with these findings, a survey of mosaic-diseased apple trees in major apple-producing provinces in China revealed that the majority of apple trees showing mosaic symptoms in China are infected with ApNMV.  相似文献   
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86.
Knockdown and lethal activities of meta- and para-substituted benzyl (1R)-trans-chrysanthemates against the house fly were measured under synergistic conditions using piperonyl butoxide as an inhibitor of oxidative metabolism and NIA 16388 as an inhibitor of hydrolytic degradation. The variations in these activities were quantitatively analyzed in terms of physicochemical substituent effects using electronic, hydrophobic, and steric parameters of the aromatic substituents, and regression analysis. The most significant parameter in determining these activities is the steric bulkiness represented by the van der Waals voluem, the effect of which is highly specific to substituent positions. The substituent effects on knockdown and lethal activities against the house fly are shown to correspond well, respectively, with those on the convulsive and lethal activities against the American cockroach. The relationship between these symptomatic activities against the house fly and the neurophysiological activities determined by using excised nerve cords from American cockroaches were also quantitatively analyzed. Each house fly symptomatic activity was found to be analyzable by a linear combination of the neuroexcitatory and neuroblocking activity indices when the transport factor was separated by using the hydrophobicity parameter.  相似文献   
87.
The mechanism of chiiling-injury in fruits of eggplants (Solanum melongena L. cultivar ‘Hyonaga’) was investigated by determining the sugar and organic acid content during cold storage and after exposure to low temperature for various periods. Fructose, glucose and maltose were detected, and totalled more than 96% of total sugar on the initial day. Total sugar content increased to 30% higher than the initial day after 2 days of cold storage, and after that decreased gradually, while in 20° C-stored fruits it decreased sharply. Fructose, glucose and maltose increased rapidly after transfer from 1° C to 20° C. Succinic, oxalic, malic and citric acid were detected before storage. Malic and citric acid were found to be the main organic acids. The ratio of malic/citric acid in fruits stored at 1°C decreased during storage, while after storage at 20°C it increased. The ratio in fruits after transfer from 1°C to 20°C increased rapidly during the time course. The ratio of malic/citric acid ranged from 6.0 to 6.8 in healthy fruits, while it was below 5.9 or above 7.3 in chilled fruits. It is suggested that according to this ratio the degree of chilling-injury of eggplant fruits might be foreseen.  相似文献   
88.
A high prevalence of larval Echinococcus multilocularis (Em) infection was found in zoo primates in Hokkaido, Japan. In October 1997, a Japanese monkey (Macaca fuscata) died and histopathologically diagnosed as alveolar hydatidosis. Serum samples were collected from the remaining Japanese monkeys and examined for antibodies against Em by enzyme-linked immunosorbent assay and western blotting. Serological tests showed 12 more animals of the remaining 57 monkeys were possibly infected. Ultrasonography revealed that nine of these 12 animals had a cystic lesion in the liver. The band patterns of western blotting in the monkeys were very similar to those in human.  相似文献   
89.
The dependence of dispersion in a tidal creek on the vegetation density in a fringing mangrove swamp is discussed through a numerical model. A secondary circulation prevails everywhere in the tidal creekmangrove swamp system and is generated by the overflow into the swamp at every high tide. As a result, dissolved and suspended matter moving with the circulation is trapped in the swamp for a fraction of the tidal cycle; it flows out of the swamp at ebb tide and disperses in the creek. The relation between the dispersion coefficient and the mangrove vegetation density is shown to be nonlinear. Dispersion is large both for bare and high vegetation densities and minimum for intermediate vegetation density. The ecological and management applications may be profound as our study suggests that such systems may be unstable and cannot naturally recover from excessive anthropogenic disturbances.  相似文献   
90.
Legume seeds contain 7S and/or 11S globulins as major storage proteins. The amino acid sequences of them from many legumes are similar to each other in the species but different from each other, meaning that some of these proteins from some crops exhibit excellent functional properties. To demonstrate this, we compared protein chemical and functional properties (thermal stability, surface hydrophobicity, solubility as a function of pH, and emulsifying properties) of these proteins from pea, fava bean, cowpea, and French bean with those of soybean as a control at the same conditions. The comparison clearly indicated that the 7S globulin of French bean exhibited excellent solubility (100%) at pH 4.2-7.0 even at a low ionic strength condition (mu = 0.08) and excellent emulsion stability (a little phase separation after 3 days) at pH 7.6 and mu = 0.08, although the emulsions from most of the other proteins separated in 1 h. These results indicate that our assumption is correct.  相似文献   
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