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81.
截形叶螨抗药性主导机制的研究 总被引:10,自引:0,他引:10
研究室内汰选培育的截形叶螨(Tetranychus truncatus Ehara)抗性种群表明,截形叶螨抗久效磷的主导机制可能是乙酰胆碱酯酶(AchE)敏感性降低,谷胱甘肽—S—转移酶(GST)和多功能氧化酶(MFO)活性升高。抗三氟氯氰菊酯截形叶螨的主导机制是MFO和羧酸酯酶活性增强,以及羧酸酯酶发生变构,对底物(α—NA)的亲和力(R/S=5)和比活力(R/S=2)上升。生物测定结果TPP、SV_1和PBo对三氟氯氰菊酯都有增效作用,增效比值分别为2、3和6倍。截形叶螨抗三氯杀螨醇的主导机制是GST代谢毒物的能力增强,GST比活力上升(R/S=2),CH_3I对三氯杀螨醇有一定增效作用(2倍)。 相似文献
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84.
The red spider miteTetranychus evansi (Acari: Tetranychidae) Baker and Pritchard was recorded for the first time in Greece, in the area of Tympaki (south-central
Crete) onSolanum nigrum. T. evansi is a pest of crops of the family Solanaceae, which are grown extensively in Crete. The species identification was based on
both morphological and molecular data. The second internal transcribed spacer was PCR amplified and sequenced in samples from
Crete. Sequences were compared with the sequence ofT. evansi from Brazil and with the ITS2 sequences (retrieved from GenBank) of the two closely related tetranychid species most commonly
found in Greece,Tetranychus turkestan andTetranychus urticae. 相似文献
85.
稻田不同种植模式对蜘蛛群落的影响 总被引:4,自引:0,他引:4
2002~2004年对湖南省湘阴县藠头—水稻轮作模式和西瓜—水稻镶嵌种植模式示范基地的稻田蜘蛛进行实地调查,分析了这2种水稻种植模式中蜘蛛群落结构和季节消长动态。结果表明,西瓜—水稻模式田的物种丰富度(44)及多样性指数(4.259 54)最高;其次为藠头—水稻模式田,其物种丰富度为41、多样性指数为4.213 10;最低的是常规的双季早、晚稻田,早、晚稻的物种丰富度分别为38和32,多样性指数分别为4.110 54和3.947 63。说明采用前2种稻田种植模式,不但丰富了稻田景观元素,而且天敌蜘蛛种群数量和种类均有较显著增加。在水稻大面积种植区推广水旱轮作或间作经济作物的耕作模式,可有效地保护稻田蜘蛛等天敌,控制害虫。同时,可提高单位土地的经济效益,增加农民收入。 相似文献
86.
Summary The role of plant breeding and particularly of host plant resistance in integrated control is discussed. Host plant resistance to insects and mites, especially to Tetranychus urticae is reviewed. A standard terminology for disease and pest resistance is recommended. 相似文献
87.
We have previously found an accession of Lycopersicon pimpinellifolium (Jusl.) Mill. (`TO-937') that appeared to resist attack by the two-spotted spider mite (Tetranychus urticae Koch). L. pimpinellifolium is a very close relative of the cultivated tomato (Lycopersicon esculentum Mill.) and thereby a potential source of desirable traits that could be introgressed to the crop species. The objective of
this study was to investigate the genetics of the resistance present in `TO-937'. Resistance to infestation by the spider
mite was quantified in 24-plant plots of L. pimpinellifolium accessions `TO-937' and `PE-10', L. pennellii accession `PE-45', L. esculentum cultivars `Moneymaker', `Roma' and `Kalohi' (reported to be partially resistant: Stoner & Stringfellow, 1967), and the interspecific
F1 cross, L. esculentum `Moneymaker' × L. pimpinellifolium `TO-937'. Only `TO-937', the F1, and`PE-45' were found to be resistant. Resistance of `TO-937' was complete when evaluated in two small greenhouses completely
planted with `TO-937' so as to simulate the genotypic homogeneity usual in commercial crops. Generations (P1, P2, F1, F2, BC1P1, and BC1P2) of a P1 (susceptible) × P2 (resistant) cross (`Moneymaker' × `TO-937') were studied for resistance in a single-plant per plot design. Resistance of
`TO-937' was inherited with complete dominance and appeared to be controlled by either two or four genes according to whether
segregation in the F2 or the BC1P1, respectively, were considered. However, calculation of the number of genes involved in the resistance was complicated by
negative interplot interference due to the high frequency of resistant genotypes within most of the generations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
88.
89.
Effects of Droplet Distribution on Insecticide Toxicity to Asian Corn Borers ( Ostrinia fumaeafis) and Spiders (Xysticus ephippiatus) 总被引:2,自引:0,他引:2
Distribution of horizontal boom produced droplets downwards into maize canopies at flowering period and its effects on the efficacies of emamectin benzoate, lambda-cyhalothrin and chlorantraniliprole against the second generation of Asian corn borer (ACB) larvae and their toxicity to spiders were studied. When insecticides were sprayed downwards into the maize canopies, randomly filtering out droplets by upper leaves led to great variations of droplet coverage and density within the canopies. Consequently, the efficacies of lambda-cyhalothrin and emamectin benzoate against ACB larvae were decreased because of randomly filtering out droplets by upper leaves. But field investigation showed that lambda-cyhalothrin was extremely toxic to hunting spiders, Xysticus ephippiatus, and not suitable to IPM programs in regulation of the second generation of ACB. Therefore, randomly filtering out droplets by upper leaves decreased lambda-cyhalothrin's efficacy against ACB larvae, but did little to decrease its toxicity to X. ephippiatus. Amamectin benzoate can reduce the populations of X. ephippiatus by 58.1-61.4%, but the populations can recover at the end of the experiment. Chlorantraniliprole was relatively safe to X. ephippiatus. It only reduced the populations of X. ephippiatus by 22.3-33.0%, and the populations can totally recover 9 d after application. 相似文献
90.
江西黎川岩泉自然保护区蜘蛛研究初报 总被引:12,自引:2,他引:12
报道了江西岩泉自然保护区蜘蛛调查结果。目前已发现的蜘蛛计25科72属148种.其中江西新记录种77种;除此之外,还有未确定种16种。 相似文献