甲胺磷对褐稻虱繁殖力影响的初探

<正> 褐稻虱Nilaparvata lugens Stal是我国南方稻区的主要害虫,“再增猖獗”现象十分明显。本试验取常用农药甲胺磷对褐稻虱的产卵量进     

溴氰菊酯和甲胺磷引起稻飞虱再猖獗问题的研究

室内测定和田间试验的结果表明,溴氰菊酯引起稻飞虱再猖獗的现象非常明显,其原因首先是稻飞虱对溴氰菊酯具有极高的自然耐药力,连续施药以后,耐药力还会进一步提高;其次是药剂会使飞虱的产卵量增多,并杀伤天敌。这种再猖獗在用药量偏低时更为明显。甲胺磷在常用剂量下,对飞虱的再猖獗不明显。     

卵黄原蛋白在昆虫生理猖獗机制中的作用及应用前景

卵黄原蛋白（Vitellogenin,Vg）是雌性昆虫卵子成熟与胚胎发育的关键因子。昆虫Vg作为一种重要的生殖相关蛋白可以直接参与昆虫发育和产卵等重要生理过程,在害虫猖獗危害中起重要作用。另外,保幼激素、蜕皮激素等激素对Vg的合成具有严密地调控作用。本文综述了Vg在昆虫猖獗中的作用以及昆虫的内分泌激素如何通过调控Vg的表达而影响昆虫的猖獗为害,总结了利用Vg作为杀虫剂靶标的应用前景,旨在为了解Vg在昆虫生理猖獗中的作用机理及害虫防治应用前景提供参考,以期为探索新的害虫防治技术提供思路。     

多次交配对小菜蛾精包形成与生殖力的影响

【目的】小菜蛾Plutella xylostella是主要为害十字花科作物的一种世界性害虫,强大的生殖能力是其成为田间最难防治的害虫的主要原因之一。交配是营两性生殖昆虫繁衍后代必要的一个生理过程,明确小菜蛾雌雄成虫的交配行为及交配后的生理响应,对于小菜蛾种群监测和综合防治具有重要意义。【方法】解剖观察小菜蛾成虫生殖腺及精包形成;利用行为学与生物学实验,测定和分析小菜蛾成虫交配与再交配能力、精包形成与消化,以及交配次数对精包形成以及雌虫生殖力的影响。【结果】小菜蛾雄成虫在交配过程中精液以精包的形式传递给雌成虫,在交配囊中精包呈白色、不透明、气球状结构,交配结束后精包可被充分消化和吸收。成虫交配能力观测结果显示,小菜蛾雌雄成虫均具有多次交配行为。首次交配后,雄成虫表现出短暂的再交配延迟,20 min内其交配成功率为54.6%,显著低于首次交配。虽然交配次数不会影响雄成虫的交配时长,但雄成虫交配史对其自身的精包大小以及雌成虫的生殖力均具有显著的抑制作用。雌成虫表现出明显的再交配抑制性,交配过的雌成虫在12 h内的交配率显著低于未交配雌成虫的,这可能取决于首次交配后精包的消化和吸收速率。雌成虫多次交配后,其产卵量和卵孵化率与单次交配的相比没有显著差异。【结论】多次交配会使小菜蛾雄成虫再交配延迟,雌成虫再交配受到抑制;多次交配产生的雄成虫精包显著减小,雌成虫产卵量与卵孵化率并没有从多次交配中获得收益。本研究为解析小菜蛾雌雄成虫生殖调控机制奠定理论基础。     

农药诱导害虫再猖獗的研究

害虫再猖獗是化学防治的3个负效应之一。农药的使用剂量、次数、使用方式以及导致植物营养变化等因素都可能引发害虫再猖獗。文章重点论述产生害虫再猖獗的原因和研究现状,并讨论再猖獗的今后研究方向。期望在害虫综合治理中能对再猖獗问题引起足够的重视。     

几种杀虫剂亚致死中量对褐稻虱生殖力影响的初报

<正> 五十年代,由于大量使用氯代烃类(六六六、DDT、毒杀芬等),有机磷等以后,引起害虫再猖獗(resurgence)。 许多研究者认为引起害虫种群再猖獗的主要原因是农药使用后大量杀伤了害虫的捕食性、寄生性天敌和病原微生物所致。一些作者认为,另一原因可能使用农药后,对害虫生殖力刺激,而引起再猖獗。 Bartlett(1968)在一篇综述中列举59种农药,证实有机氯对螨类生殖力存在刺激作用。 S.Chelliah(1979)1977-79年进行杀虫剂对褐稻虱Nilaparvata lugens Stal再猖獗的一系列试验研究。其中用LD_5、LD_(10)、LD_(25)、LD_(50)剂量的溴氰菊酯,甲基1605,乙滴滴处理褐稻虱,结果与对照比,用溴氰菊酯四种剂量处理     

延迟交配对昆虫生殖行为的影响以及与性信息素防治害虫的关系

对鳞翅目昆虫延迟交配对昆虫生殖力、卵孵化率、交配成功率、成虫寿命等进行了总结。雌虫延迟交配降低雌虫的生殖力、卵的孵化率及与雄虫成功交配率,但可以延长雌虫寿命。雄虫延迟交配降低雌虫的生殖力、卵的孵化率、产卵时间,雄虫的精子质量下降但寿命有所增加。已发现延迟交配在迷向法中控制害虫起着重要的作用,对进一步认识迷向法中不同作用机理以及延迟交配在迷向法防治害虫中的潜力进行了探讨。     

施用杀虫药剂引起昆虫再增猖獗的问题(二)

大部份害虫再增猖獗现象是属于这一类的,即:为了甲种害虫施用某一杀虫药剂,结果引起乙种害虫的再增或猖獗。有时,引起猖獗的害虫原来是重要的害虫,但是,也有时,因为某一药剂的施用,引起了一些原来是不重要的害虫猖獗成灾。后一类情况是最不幸的结果。 勃朗(Brown,1951)总结说,由于DDT在     

栎黄枯叶蛾羽化及生殖行为研究

栎黄枯叶蛾Trabala vishnou gigantina Yang是近年在沙棘(Hippophae rhamnoides)林中大面积暴发的一种食叶害虫。通过野外调查和室内饲养观察相结合对该虫的羽化、交配和产卵等行为等进行了研究。结果表明,栎黄枯叶蛾羽化期40 d左右,羽化高峰期为9月上旬,日羽化高峰出现在傍晚17:00—23:00,占全天羽化量的82.46%;雌雄性比为1∶1.41;交配高峰期发生在凌晨3:00—4:00,成虫羽化翌日开始进行交尾,2日龄雌蛾交配率最高,达到45.6%,随后交配率逐步降低。雌蛾一生只交尾1次,雄蛾可进行多次交尾。成虫交配持续时间多为14¹6 h。成虫交配后即可产卵,产卵主要在夜间进行,产卵高峰期在2:00—6:00,占全天产卵量的82.40%。未交配雌蛾和雄蛾的平均寿命为11.05 d和9.85 d;显著高于已交配雌蛾和雄蛾的8.05 d和7.35 d,说明交配可明显缩短雌雄成虫寿命。     

眉斑并脊天牛生物学特性研究

眉斑并脊天牛Glenea cantor Fabricius是我国华南地区园林绿化植物木棉树的重要蛀干害虫。本试验通过室内饲养观察和野外调查,对该虫的生物学特性进行了研究。结果表明该虫在南宁一年发生4代,平均世代历期为70 d,主要以4龄幼虫在受害枝干内越冬。成虫羽化后出木前期为5.97±1.11 d。雄虫较雌虫提早羽化2-3 d,成虫期需补充营养,且具弱趋光性和假死习性。在日节律中,9∶00-11∶00和14∶00-16∶00为产卵高峰期,16∶00-19∶00为交配高峰期。雌虫出木后2 d开始交配,雄虫出木后4 d开始交配。雌雄虫一生可交配15.12±7.02次,每次交配时长为3.23±0.97 h,一天内仅交配一次。成虫主要趋向长势较弱的木棉树及枝条上产卵。产卵前期为13.50±3.15 d,平均产卵量为117.31±33.25粒。雌雄寿命分别为72.34±15.60 d和46.22±14.38 d。     

Modelling pest population resurgence due to recolonization of fields following an insecticide application

1. To investigate the effect of insect recolonization on the insecticide-induced resurgence of crop pests, a modified Lotka–Volterra predator–prey model was partitioned into two areas, 'sprayed' and 'unsprayed'.
2. The unsprayed area provided a source of insects to recolonize the sprayed area, resulting in a change in pest dynamics in both areas following an insecticide application.
3. Model sensitivity to insecticide selectivity and rates of predation, insect dispersal and pest population increase were examined.
4. Resurgence risk in the sprayed area increased with increasing pest dispersal rate, but decreased with increasing predator dispersal rate.
5. Pest resurgence could also occur in the unsprayed area, especially when prey dispersal rates were low. The extent of resurgence in the unsprayed area could in some circumstances be worse than in the sprayed area itself.
6. The more efficient and longer-lived the predators, the greater the level of pest resurgence in both areas following insecticide use.
7. More selective insecticides, killing the pest, but not the predator, reduced resurgence provided that the average life-span of the predators was reasonably long. Even highly selective insecticides could cause resurgence of the pest in the unsprayed area.
8. When the prey carrying capacity of the unsprayed area was increased relative to that of the sprayed area, resurgent effects in the unsprayed area were reduced, but could still be significant under some circumstances.     

RNA干扰技术在昆虫学领域研究进展

RNA干扰(RNAi)是生物体内源基因发生转录后特异性降解的一种生理现象,广泛存在于生物体内。RNAi主要由小干扰RNA诱发阻碍目的基因的翻译或转录,造成目标信使RNA沉默。RNAi具有高效、特异性强等优点,被广泛应用于昆虫基因功能研究,并显示出了开发新型病虫害管理策略的巨大潜力。主要阐述了RNAi的沉默机制,双链RNA转入昆虫体内的几种方式,以及RNAi技术在不同目昆虫中研究的最新进展。最后,对RNAi技术存在的不足之处进行了简单总结,还对RNAi技术在害虫防治中的应用进行了展望,以期为该技术广泛应用于农业害虫防治提供理论支持。     

Optimum timing for integrated pest management: Modelling rates of pesticide application and natural enemy releases

Many factors including pest natural enemy ratios, starting densities, timings of natural enemy releases, dosages and timings of insecticide applications and instantaneous killing rates of pesticides on both pests and natural enemies can affect the success of IPM control programmes. To address how such factors influence successful pest control, hybrid impulsive pest-natural enemy models with different frequencies of pesticide sprays and natural enemy releases were proposed and analyzed. With releasing both more or less frequent than the sprays, a stability threshold condition for a pest eradication periodic solution is provided. Moreover, the effects of times of spraying pesticides (or releasing natural enemies) and control tactics on the threshold condition were investigated with regard to the extent of depression or resurgence resulting from pulses of pesticide applications. Multiple attractors from which the pest population oscillates with different amplitudes can coexist for a wide range of parameters and the switch-like transitions among these attractors showed that varying dosages and frequencies of insecticide applications and the numbers of natural enemies released are crucial. To see how the pesticide applications could be reduced, we developed a model involving periodic releases of natural enemies with chemical control applied only when the densities of the pest reached the given Economic Threshold. The results indicate that the pest outbreak period or frequency largely depends on the initial densities and the control tactics.     

昆虫卵黄蛋白及其激素调控的研究进展

卵黄蛋白的结构及其合成、摄取过程与激素的调控机理是目前昆虫生理学的研究热点之一。近几年,随着分子克隆技术、基因工程手段和生物信息学的发展,对卵黄蛋白基因的研究将为寻找害虫生物防治提供新途径。本文对昆虫卵黄蛋白及其激素调控进行了综述。为防治害虫再猖獗的发生和促进大量繁殖益虫提供重要的理论依据。     

臭虫的再猖獗、生物学及防治研究进展

由于DDT等现代杀虫剂的问世,臭虫在20世纪40-50年代以后在全球大部分地区尤其是发达国家和地区销声匿迹,但近10多年来臭虫在部分国家和地区重新出现.本文对其再猖獗原因、生物学和行为、饲养、抗药性、监测与防治策略进行了综述,旨在引起国人的重视,对今后臭虫的监测和防治起到抛砖引玉的作用.本文分析了近15年有关温带臭虫Cimex lectulariusL.和热带臭虫C.hemipterus(F.)的研究文献.臭虫再猖獗被认为是因为它对目前使用的杀虫剂例如拟除虫菊酯类等产生抗性以及频繁的地区及国际交往等因素造成的.简单、经济和大规模臭虫种群饲养方法——人工膜饲喂法的研发为我们开展臭虫生物学和生态学研究提供了便利.控制和根除臭虫目前仍较困难,采用害虫综合治理(integrated pest management,IPM)策略,包括臭虫知识宣传、主动监测、非化学防治方法(例如:经常洗涤床上用品、蒸汽熏蒸、热处理、使用床垫罩、在家具腿下放置臭虫拦截装置)、有选择使用杀虫剂以及定期监测及反复防治等措施,可达到很好的防控效果.在我国部分地区,臭虫发生也呈上升趋势,工人宿舍和火车车厢是常见的臭虫为害环境.有必要对我国臭虫发生现状及其抗药性进行调查与监测.还应借鉴国际先进技术,研制出我国适用的、有效的监测工具和防治方法,并根据我国具体国情制定出切实可行的防治标准.同时积极开展臭虫科普宣传,做到早发现、早防治,防止臭虫再猖獗和扩散.     

Economic Thresholds in Soybean-Integrated Pest Management: Old Concepts, Current Adoption, and Adequacy

Increasing global demands for food underline the need for higher crop yields. The relatively low costs of the most commonly used insecticides in combination with increasing soybean market prices led growers and technical advisors to debate the adequacy of recommended economic thresholds (ETs). The adoption of ETs and pest sampling has diminished in Brazil, leading to excessive pesticide use on soybean. The reduced efficacy of natural biological control, faster pest resurgence, and environment contamination are among the side-effects of pesticide abuse. To address these problems and maximize agricultural production, pest control programs must be guided by a proper integrated pest management (IPM) approach, including the ET concept. Therefore, the most appropriate time to initiate insecticide spraying in soybean is indicated by the available ETs which are supported by experiments over the last 40 years in different edapho-climatic conditions and regions with distinct soybean cultivars. Published scientific data indicate that preventive insecticide use is an expensive and harmful use of chemicals that increases the negative impact of pesticides in agroecosystems. However, the established ETs are for a limited number of species (key pests), and they only address the use of chemicals. There is a lack of information regarding secondary pests and other control strategies in addition to insecticides. It is clear then that much progress is still needed to improve ETs for pest management decisions. Nevertheless, using the current ETs provides a basis for reducing the use of chemicals in agriculture without reducing yields and overall production, thereby improving sustainability.     

浅谈害虫成虫防治技术

目前害虫防治中的一系列问题如害虫幼虫抗药性上升、害虫天敌被大量杀伤、人畜中毒、环境污染与土壤农药残毒日趋严重 ,使以成虫为目标虫态或防治对象而开展的成虫防治策略被广为接受并广泛应用。本文对目前使用的各种成虫防治技术体系进行了概括 ,并列举了成虫防治技术的特点和优点 ,以及进行成虫防治的许多实例。其中信息化合物防治和遗传防治的飞速发展为成虫防治的应用提供了多种途径。     

Mitigating the effects of insecticides on arthropod biological control at field and landscape scales

Integrated pest management (IPM) programs emphasize the combination of tactics, such as chemical and biological control, to maintain pest populations below economic thresholds. Although combining tactics may provide better long-term sustainable pest suppression than one tactic alone, in many cases, insecticides and natural enemies are incompatible. Insecticides can disrupt natural enemies through lethal and sub-lethal means causing pest resurgence or secondary pest outbreaks. Legislative actions such as the Food Quality Protection Act (US) and the Directive on Sustainable Use of Pesticides (EU) have placed greater restrictions on insecticides used in agriculture, potentially enhancing biological control. Here we focus on the effects of insecticides on biological control, and potential mitigation measures that can operate at different scales. At the farm scale, natural enemies can be conserved through the use of selective insecticides, low doses, special formulations, creation of refugia, special application methods, and targeted applications (temporal or spatial). At the landscape scale, habitat quality and composition affect the magnitude of biological control services, and the degree of mitigation against the effects of pesticides on natural enemies. Current research is teasing apart the relative importance of local and landscape effects of pesticides on natural enemies and the ecosystem services they provide, and the further development of this area will ultimately inform the decisions of policy makers and land managers in terms of how to mitigate pesticide effects through habitat manipulation.