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141.
香柏原产于北美(N35°~50°)地区,与黑龙江省纬度相近,其自然分布区极端最低气温-41℃,低于黑龙江省多数地区。引种试验表明:香柏在黑龙江省黑河地区、哈尔滨市苗期生长正常,4a生播种苗苗高达40~50 cm,3a生扦插苗苗高达40 cm以上,具有较强的适应性。用做绿蓠效果优于现有树种。  相似文献   
142.
西花蓟马传播病毒病的研究进展   总被引:6,自引:0,他引:6  
西花蓟马[Frankliniella occidentalis (Pergande)]是一种世界性的重要农业害虫,目前在69个国家和地区已有报道。西花蓟马能以持久性的方式传播番茄斑萎病毒属(Tospovirus)的病毒,所传播病毒造成的经济损失远远大于其本身所造成的损失。因此,许多学者对西花蓟马及其传播的番茄斑萎病毒属病毒进行了大量研究。本文主要综述了近年来西花蓟马传播病毒的种类、番茄斑萎病毒属病毒的结构以及西花蓟马的传毒机制等方面的研究进展。  相似文献   
143.
花生花蓟马室内药剂筛选及田间药效试验   总被引:1,自引:0,他引:1  
采用浸叶法在室内对花蓟马进行了药剂筛选试验,并对毒效较高的3种药剂开展了进一步毒力测定和田间药效试验。结果表明,有机磷类的三唑磷和乐斯本,拟除虫菊酯类的高效氯氰菊酯、溴氰菊酯和高效氯氟氰菊酯,以及氨基甲酸酯类的丁硫克百威等药剂对花蓟马的毒效很低,致死率均在37.6%以下。阿维菌素、啶虫脒和吡虫啉对花蓟马的致死作用明显,致死率分别为98.3%、98.7%和66.8%,它们的LC50分别为0.97mg·L^-1、15.4mg·L^-1和42.4mg·L^-1,以阿维菌素的毒力最高,是吡虫啉的43.71倍。田间药效试验结果与室内毒力测定结果相符合,以阿维菌素的防效最高,达93.3%以上,且持效期较长,施药后12d的防效仍在90%以上,是防治花生花蓟马的首选药剂。  相似文献   
144.
BACKGROUND: Biological control of phytophagous mites in orchards requires that pesticides used to manage other arthropod pests or diseases are harmless to predacious mites, as these are essential to keep phytophagous mites at non‐injurious population levels. This study evaluates the possible toxic attributes of acetamiprid, imidacloprid, thiacloprid, thiamethoxam, spirodiclofen, spinosad and methoxyfenoxide currently used in western Canadian orchards. RESULTS: None of these pesticides has any ovicidal properties against Galendromus occidentalis (Nesbitt). Imidacloprid and acetamiprid were highly toxic to the adults and reduced fecundity significantly. Thiamethoxam and spirodiclofen were non‐toxic to adults, but they slightly reduced fecundity. Thiacloprid, spinosad and methoxyfenoxide were harmless to adults and had no effect on fecundity. All compounds showed some repellence at 24 h intervals for 72 h. CONCLUSIONS: Imidacloprid and acetamiprid are incompatible with IPM programs because they are toxic to adults and negatively affect fecundity. Thiamethoxam and spirodiclofen need further field evaluation to determine if they are compatible with IPM programs because they slightly reduced fecundity. Thiacloprid, spinosad and methoxyfenoxide are harmless to adults, but they are slightly repellent. Therefore, with the exception of imidacloprid and acetamiprid, all these compounds should be field tested for compatibility in an IPM program. © Her Majesty the Queen in Right of Canada, as represented by the Minister of Agriculture and Agri‐Food Canada. Published by John Wiley & Sons, Ltd  相似文献   
145.
亚致死浓度多杀菌素对西花蓟马解毒酶系活力的影响   总被引:3,自引:1,他引:2  
采用亚致死浓度(LC25)多杀菌素对西花蓟马Frankliniella occidentalis相对敏感(SS)种群进行连续选育,获得亚致死(Sub)种群。处理36代后,Sub种群对多杀菌素的敏感性下降到SS种群的5.2倍。用SS和Sub种群各自的LC10和LC25浓度多杀菌素分别处理两种群的2龄若虫,1、6 、12、24和48 h后测定羧酸酯酶(CarE)、谷胱甘肽S-转移酶(GSTs) 和多功能氧化酶(MFOs)的比活力。结果表明,Sub种群对照组CarE和GSTs比活力在除第48 h外的其他时间段都高于SS种群对照组,且6 h时两者CarE比活力差异显著,Sub种群是SS种群的1.37倍;Sub种群对照组MFOs比活力在各时间段都高于SS种群对照组,在1 和6 h时差异显著,前者分别是后者的1.62和1.36倍。再经各自的LC10和LC25浓度多杀菌素处理后,在各时间段Sub种群的CarE比活力均高于SS种群;LC25浓度处理后,Sub种群的GSTs和MFOs比活力虽在短时间内低于SS种群,但随处理时间的延长其比活力均高于SS种群。说明SS种群经亚致死浓度多杀菌素选育36代后,其体内CarE、GSTs和MFOs比活力有上升趋势;继续用亚致死浓度多杀菌素处理,则Sub种群体内解毒酶活力的动态调节能力要强于SS种群。  相似文献   
146.
为了研发靶标害虫为西花蓟马的球孢白僵菌杀虫剂,我们首先通过筛选、纯化和复壮获得对西花蓟马高效的真菌菌株;其次,对液-固双相发酵条件和发酵工艺进行优化;然后,改良了产品剂型和配方;最后对产品进行环境和毒性评价。结果显示该产品各项指标均符合国家标准。150亿孢子/g球孢白僵菌可湿性粉剂于2018年在国内获审批登记。喷施1800~3000 g/hm2对辣椒上西花蓟马的防效均为74%以上。推荐用量为2400 g/hm2。该产品的研发和获批登记为西花蓟马的生物防治奠定了坚实的基础。  相似文献   
147.
The major mechanism of resistance to most insecticides in Frankliniella occidentalis (Pergande) is metabolic, piperonyl butoxide (PBO) suppressible, mediated by cytochrome-P450 monooxygenases and conferring cross-resistance among insecticide classes. The efficacy of insecticide mixtures of acrinathrin, methiocarb, formetanate and chlorpyrifos was studied by topical exposure in strains of F. occidentalis selected for resistance to each insecticide. The method consisted in combining increasing concentrations of one insecticide with a constant low rate of the second one as synergist. Acrinathrin activity against F. occidentalis was enhanced by carbamate insecticides, methiocarb being a much better synergist than formetanate. Monooxygenase action on the carbamates would prevent degradation of the pyrethroid, hence providing a level of synergism by competitive substrate inhibition. However, the number of insecticides registered for control of F. occidentalis is very limited, and they are needed for antiresistance strategies such as mosaics and rotations. Therefore, a study was made of the synergist effect of other carbamates not used against thrips, such as carbofuran and carbosulfan, against a susceptible strain and a field strain. Neither carbamate showed synergism to acrinathrin in the susceptible strain, but both did in the field strain, carbosulfan being a better synergist than carbofuran. The data obtained indicate that low rates of carbamates could be used as synergists to restore some pyrethroid susceptibility in F. occidentalis.  相似文献   
148.
The effectiveness of trap cropping as an integrated control strategy against western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), was explored in potted chrysanthemum, Dendranthema grandiflora (Tzvelev), greenhouse crops. The efficacy of flowering chrysanthemum trap plants, either treated with the insecticide spinosad or untreated, to regulate F. occidentalis populations was tested at different spatial scales (small cage, large cage and commercial greenhouse) and for different time periods (1 or 4 weeks). It was demonstrated that flowering chrysanthemums as trap plants lower the number of adult F. occidentalis in a vegetative chrysanthemum crop and, as a result, reduce crop damage. In the 4 week large-cage trial and the commercial trial, significant differences between the control and the trap plant treatments started to appear in the third week of the experiment. Larvae were only significantly reduced by the presence of trap plants in the 1 week small-cage trials. There were no significant differences between treatments with spinosad-treated and untreated trap plants in the number of F. occidentalis on the crop. This suggests that there was minimal movement of adult F. occidentalis back and forth between the trap plants and the crop to feed and oviposit. It is concluded that the trap plant strategy is a useful tool for integrated pest management against F. occidentalis in greenhouses.  相似文献   
149.
以香柏(Thuja occidentalis)枝叶为原料、NaCl溶液作为盐析试剂,采用盐析-水蒸气蒸馏法提取香柏精油。设计单因素试验考察了料液比、NaCl溶液的浓度、浸泡时间以及蒸馏时间对香柏细枝叶精油提取率的影响,并采用正交试验优化香柏精油的提取工艺。结果表明,优化的香柏精油提取工艺为料液比1∶15.0(m∶V,g/mL),盐析试剂为质量分数4%的NaCl溶液,浸泡6 h,蒸馏3 h。在此条件下,香柏精油提取率可达1.83%。  相似文献   
150.
中华草蛉3龄幼虫对西花蓟马的捕食作用   总被引:3,自引:1,他引:2  
室内观察测定了中华草蛉3龄幼虫对西花蓟马的捕食功能反应和搜寻效应。结果表明,26℃条件下该捕食功能反应符合HollingⅡ型方程。随着猎物密度的增加,中华草蛉3龄幼虫对西花蓟马成虫、若虫的捕食量增加,搜寻效应降低,捕食上限分别为625.0头/d和714.3头/d。  相似文献   
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