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11.
朱砂叶螨羧酸脂酶最优测试条件的选择   总被引:1,自引:0,他引:1  
应用二次回归通用旋转组合设计,对朱砂叶螨离体羧酸酯酶测试过程中所需缓冲液pH值、恒温时间、反应温度及底物浓度,设立4因子5水平试验,在考虑4个因子主效应和互作效应的情况下,筛选测试羧酸酯酶的最优条件组合。  相似文献   
12.
Four fluvalinate formulations differed in their residual toxicity to female two-spotted spider mite (TSM), Tetranychus urticae adults; the emulsifiable concentrate (EC) was the most toxic. In contrast, there was little difference in toxicity between the formulations with the European red mite (ERM) Panonychus ulmi with the exception of the EC formulation which was the least toxic. Fluvalinate 2F caused minimal (<10%) TSM and ERM egg mortality. Fluvalinate 2F was more toxic and caused greater larval dispersal for the TSM compared to the ERM at the field concentration and below. The toxicity of fluvalinate 2F to TSM and ERM protonymphs, deutonymphs and adults was low, approximately <20% at field concentration. Dispersal was the main response to fluvalinate and this was positively correlated with increasing concentration. The combined mortality and dispersal LC50 was five times lower for ERM protonymphs and adults, but 11 times higher for ERM deutonymphs compared to equivalent TSM life stages. Fluvalinate 2F reduced TSM development from the protonymph and deutonymph stages to a greater extent compared to the ERM. The mortality response to fluvalinate 2F was unaffected by host type (peach or apple) for the TSM whereas ERM mortality was higher on apple compared to peach. TSM dispersal was higher from apple compared to peach whereas ERM dispersal was similar on both host types. Oviposition by both mite species was lower on apple than peach leaves. A 1 h exposure to fluvalinate 2F reduced ERM oviposition for 12 days.  相似文献   
13.
统计分析表明两种叶螨间生态位重叠值较大、各自生态位宽度较大。两种叶螨的时动空间生态位与各自种群消长曲线相一致,显示了它们对资源有相似要求以及“逐步扩散整树危害”的取食危害方式。它们的生态位分离表现在叶片正、反面及叶片反面的某些小“领域”上。苹果全爪螨更喜欢分布在树冠上层和外层。统计和模糊分析都表明草蛉和小花螨与两种叶螨的时间同步和空间同域性较强,捕食螨与叶螨的时间生态位重叠较小,而空间生态位重叠较大。天敌与叶螨间的时空生态位重叠以及天敌食谱生态位宽度结合分析有助于合理评价天敌的控制作用。  相似文献   
14.
Populations of the two-spotted spider mite, Tetranychus urticae Koch collected from various localities and from various host plants in Japan showed wide variations in diapause attribute. Diapause percentages at 18°C/9L15D varied from nearly 100% in the north to 0% in the south-west. At intermediate latitudes the mites showed wide inter-population variations. Populations on herbaceous hosts in vinyl- or glass-houses gave significantly lower incidence of diapause than those on roses and deciduous fruit trees. Presence of winter hosts and better host quality under protected environments seemed to favour non-diapausing mites. The temperature threshold for diapause expression also varied widely among local populations. Northern populations consistently had higher and less variable thresholds than populations at intermediate latitudes with thresholds between 15 and 18°C. Inbred lines derived from a population in Kyoto exhibited a wide variation in diapause percentage at 18°C. These results show that diapause in T. urticae is a quantitative threshold trait and that populations in central Japan consist of a variety of genotypes with different diapause traits. This might provide a genetic source for adaptation to local and temporal variations in environmental conditions.  相似文献   
15.
The incidence of predation of eight species of predacious mirids (Hemiptera: Miridae) present in an apple orchard of Québec on the green apple aphid, two-spotted spider mite and European red mite were investigated. The daily consumption rates varied from 1–2 green apple aphids forHyaliodes vitripennis Say andCampylomma verbasci Meyer to 7–9 aphids forDeraeocoris fasciolus Knight andLepidopsallus minisculus Knight.H. vitripennis consumed significantly more mites than the other mirid species with 26 and 18 mites per day for the two-spotted spider mite and the European red mite respectively. The combined use ofH. vitripennis andL. minisculus is suggested for the control of phytophagous mites. This paper is contribution No. 335/91.06.02R, Research Station, Agriculture Canada, Saint-Jean-sur-Richelieu, Québec, Canada.  相似文献   
16.
The pyrethroid fenvalerate showed significantly faster activity against adult two-spotted spider mite Tetranychus urticae Koch c.f. azinphosmethyl using broad bean leaf discs sprayed in a Potter tower. LC50s for fenvalerate were similar at 24 and 48 hr (0.056 and 0.051g AI/1) while LC50s for azinphosmethyl were significantly different at 24 and 48 hr (0.72 and 0.38g AI/1, respectively). Mortality was partitioned to run-off and direct mortality. Fenvalerate showed an increasing contribution to mortality by run-off with increasing concentration. Increasing concentrations of azinphosmethyl had no effect on the proportion of T. urticae running off the discs. Fenvalerate inhibited egg production c.f. azinphosmethyl (60% and 20% inhibition respectively c.f. control after 24hr). The effect was not permanent. Carbaryl showed no acaricidal or inhibitory effects at 1g AI/1. T. urticae detected fenvalerate residues as reflected by choice of oviposition sites on untreated halves of leaf discs c.f. treated halves. Azinphosmethyl had no effect on oviposition preference. Phytoseiid mites were highly sensitive to fenvalerate residues. Predators moved off the test arena into sticky barriers after feeding on fenvalerate-treated eggs or walking on glass slides treated at 0.00005g AI/1.
Résumé Les insecticides pyrethroïdes ont été utilisés pour lutter contre les pullulations d'araignées rouges. Cette note examine les réponses de Tetranychus urticae Koch et des prédateurs phytoseiidés résistants aux organo-phosphorés, Amblyseius fallacis Garman et Typhlodromus occidentalis Nesbitt, au fenvalerate (pyrethroïde) et à l'azinphosmethyl (organophosphate). Quelques essais avec du carbaryl sont indiqués.Une femelle adulte de T. urticae est placée sur une rondelle de feuille de Phaseolus vulgaris L. pulvérisée dans une tour de Potter.Les résultats sur la mortalité en fonction de la dose obtenus montrent une activité plus rapide du fenvalerate que de l'azinphosmethyl. Les DL50 du fenvalerate (0,056 et 0,051g AI/I) sont les mêmes à 24 et 48 h, tandis que l'azinphosmethyl montre une activité plus lente (DL50 de 0,72 et 0,38g AI/I à 24 et 48 h). La mortalité se partage entre la sortie de la rondelle et la mortalité in situ.Le fenvalerate provoque une plus forte répulsion que l'azinphosmethyl. Contrairement à l'azinphosmethyl le fenvalerate inhibe la production d'oeufs 60% et 20% d'inhibition à DL50 au bout de 24 h par rapport au témoin. Cette inhibition n'est pas permanente. Le carbaryl n'a pas d'effets inhibiteur ou acaricide à 1g AI/l.Les femelles adultes de T. urticae décèlent les résidus de fenvalerate sur les rondelles et pondent leurs oeufs sur les moitiés non traitées ou traitées à l'azinphosmethyl.Les Phytoseiides sont très sensibles aux résidus de fenvalerate. Après consommation d'oeufs traités, A. fallacis est incapable d'éviter des bandes gluantes. T. occidentalis décèle des traitements à 0,00005g AI/l en quittant les lames traitées par les bandes gluantes.
  相似文献   
17.
为明确饥饿程度对拟小食螨瓢虫 Stethorus (Allosstethorus) parapauperculus 控害潜能的影响,本研究通过比较不同饥饿程度下拟小食螨瓢虫对朱砂叶螨 Tetranychus cinnabarinus 的功能反应和自身密度干扰效应,探讨不同饥饿程度拟小食螨瓢虫对朱砂叶螨的捕食作用。结果表明,饥饿程度对拟小食螨瓢虫朱砂叶螨的捕食量有明显的影响,瓢虫的取食量与朱砂叶螨的密度呈正相关,表现为饥饿48 h>饥饿24 h>未饥饿;拟小食螨瓢虫对各虫态朱砂叶螨的捕食作用均符合Holling Ⅱ模型。在一定空间范围内,拟小食螨瓢虫个体间存在竞争和相互干扰,Hassell Varley模型能较好地反映拟小食螨瓢虫在捕食各虫态朱砂叶螨时受自身密度的干扰情况。在同样饥饿状态下,随着瓢虫自身密度增加,捕食效率降低,干扰效应增大。  相似文献   
18.
为了得到对朱砂叶螨(Tetranychuscinnabarinus)具有较好杀螨活性的植物精油与阿维菌素复配配方,并为杀螨剂开发应用提供指导,本研究采用喷雾法测定了柠檬草、广藿香、山鸡椒、亚洲薄荷植物精油及阿维菌素对朱砂叶螨的毒力,分别采用共毒因子法和共毒系数法评价了山鸡椒和亚洲薄荷精油对阿维菌素的增效作用和复配最佳配比.结果表明,柠檬草精油和广藿香精油基本无杀螨活性,山鸡椒精油、亚洲薄荷精油处理朱砂叶螨24h后LC50分别为772.801mg/L和1040.187mg/L.阿维菌素与亚洲薄荷1∶272,1∶679复配具有增效作用.阿维菌素与亚洲薄荷1∶400复配时共毒系数最大,可达160.因此,阿维菌素与亚洲薄荷1∶400复配防治朱砂叶螨具有明显增效作用,这为杀螨剂的开发应用研究提供了参考.  相似文献   
19.
20.
Abstract

The slug Athoracophorus bitentaculatus (Quoy & Gaimard, 1832) is redescribed from material collected in the northern third of the North Island of New Zealand. Its anatomy is described and figured, local variation in the condition of the lateral grooves and mantle is figured, and supplementary information on its biology and distribution is given. Its identity and taxonomy are discussed in the context of earlier work on the species. Evidence is presented for the reduction of Reflectopallium Burton, 1963 to synonymy with Athoracophorus Gould, 1852. A revised key to New Zealand and subantarctic genera of Athoracophoridae is given.  相似文献   
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