烟田6种常用杀虫剂对烟蚜茧蜂影响的研究

为了评估烟田常用杀虫剂对烟蚜茧蜂的安全性,本文在实验室条件下采用药膜法和浸虫法测定了6种烟田常用杀虫剂对烟蚜茧蜂（Aphidiusgifuensis）的影响。结果表明：吡虫啉、啶虫脒、噻虫嗪对烟蚜茧蜂成蜂有明显的触杀毒力,噻虫嗪和吡虫啉显著降低了烟蚜茧蜂的羽化率,且这3种杀虫剂处理僵蚜后可导致羽化出的成蜂双翅畸形; 而甲氨基阿维菌素苯甲酸盐、高效氯氟氰菊酯、吡蚜酮对烟蚜茧蜂成蜂和僵蚜均相对安全,处理1 h后成蜂死亡率为0～5.56%,僵蚜羽化率达70%以上。研究结果可为烟蚜综合防治时合理选用杀虫剂提供依据。     

菜田常用杀虫剂对小菜蛾及菜蛾绒茧蜂的选择毒杀作用

在室内测定了９种菜田常用杀虫剂对小菜蛾幼虫及其主要天敌菜蛾绒茧蜂成虫和茧的毒性。结果表明,应用厂家推荐田间防治小菜蛾的使用浓度,对小菜蛾的杀虫效果锐劲特、Ｂｔ、虫螨光可达１００％,生物复合病毒杀虫剂、宝路和抑太保可达９５％以上,杀虫双达８０％,而氰戊菊酯和万灵对小菜蛾的杀虫效果较差,供试幼虫最终化蛹率分别达７０．０％和７８．３％。让菜蛾绒茧蜂成虫接触厂家推荐浓度的药膜,接触杀虫双２小时后的死亡率即达８０％以上;１２小时后,接触锐劲特的死亡率即达１００％;２４小时后,接触万灵和杀虫双的累计死亡率达９０％以上,接触宝路和氰戊菊酯的约５０％,而接触抑太保、Ｂｔ、虫螨光和生物复合病毒杀虫剂的累计死亡率均在２０％以下,和对照无显著差异。作者认为在菜蛾绒茧蜂等天敌较为丰富的季节,虫螨光、Ｂｔ、生物复合病毒杀虫剂、宝路和抑太保应属防治小菜蛾优先选用的杀虫剂,锐劲特则主要应在小菜蛾大发生、而天敌又很少时应用。     

麦田蚜茧蜂的初步研究

武昌麦田蚜茧蜂共有5种,以燕麦蚜茧峰、烟蚜茧蜂为优势种;重寄生蜂有三种,以黄足分盾细蜂为优势种。蚜茧蜂4月中、下旬进入麦田,5月中旬种群数量达到高峰:蚜茧蜂种群数量主要受寄主—蚜虫密度和4～5月的雨量,相对湿度的影响。麦田蚜茧蜂对麦蚜有一定的控制作用,寄生率最高可达40％以上。解决好重寄生和跟随现象的问题,可提高好苗蜂对麦蚜的控制效果。     

杀虫剂对菜蚜茧蜂的影响

阐述了杀虫剂对菜蚜茧蜂的致死效应和亚致死效应,综述了莱蚜茧蜂对杀虫剂的抗性和杀虫剂对菜蚜茧蜂搜索行为及分布的影响。     

蚜茧蜂对麦蚜控制作用的初步研究

本文应用二次通用旋转组合设计的方法进行了蚜茧蜂对麦蚜寄生能力的研究,得出了蚜茧蜂的寄生量模型：Ｙ＝９１．４０＋４３．６２Ｘ１＋２０．２７Ｘ２＋７．２５Ｘ１Ｘ２－１６．８３Ｘ１＾２＋３．４３Ｘ２＾２。并对模型进行了分析,表明对总寄生量的影响因素中麦蚜密度的大小大于蚜茧蜂本身密度的大小。在试验密度范围内,蚜虫和蚜茧蜂干扰作用不明显,且有相互促进的作用,但增加速度相同。     

南宁市烟蚜其天敌—蚜茧蜂的发生和防治试验

在南宁全年种有烟苗的条件下，烟蚜种群数量高峰期分别出现在１月上旬至３月下旬和５月中旬至６月上中旬，蚜茧蜂Ａｐｈｉｄｉｕｓ ｇｉｆｕｅｎｓｉｓ Ａｓｈｍｅａｄ是烟蚜重要寄生性天敌，其种群年内也出现两个高峰期，且均分别在烟委生峰期之后。     

Biology and life table of Diaeretiella rapae against Brevicoryne brassicae on different cultivars of cauliflower

Phytoparasitica - Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae) is one of the most promising, effective and a common endoparasitoid of different aphid species including cabbage aphid,...     

Assessing the resistance of collard greens genotypes to the cabbage aphid (Brevicoryne brassicae) (Hemiptera: Aphididae)

Phytoparasitica - Severe attacks of Brevicoryne brassicae (Hemiptera: Aphididae) on brassica crops may lead to a significant decrease in yield and can cause plant death. Host plant...     

Impact of two synthetic pyrethroids and methomyl on management of the cabbage aphid,brevicoryne brassicae (L.) and its associated parasitoid,diaeretiella rapae (M'Intosh)

The effectiveness of two synthetic pyrethroids, cypermethrin and fenvalerate, and of methomyl applied to cabbage plants was tested against the cabbage aphid, Brevicoryne brassicae (L.), and its parasitoid, Diaeretiella rapae (M'Intosh). Dosage rates chosen were equivalent to the manufacturer's maximum and minimum recommendations. Methomyl was considerably more toxic to B. brassicae adults than the two synthetic pyrethroids used. Fenvalerate, at the lowest rate used (71 g ha^?1), showed satisfactory effectiveness in reducing aphid adult population on treated plants by c. 77% below that of the control. All insecticides and rates used significantly reduced the emergence of parasitoid adult D. rapae from mummified aphids compared to the control. Fenvalerate clearly had less impact on emergence than cypermethrin or methomyl at any dosage used, while methomyl has appeared to be the most toxic compound in this respect. Longevity of parasitoid adults was highly affected by insecticide application, particularly those adults emerging from mummified aphids exposed to methomyl or cypermethrin. However, only a slight difference in longevity was seen at the lower rate of 71 g ha^?1 of fenvalerate. At the lowest dosage rates used, methomyl and cypermethrin reduced the F₁-progeny of adult parasitoid females by 70.5% and 58.3%, respectively, of the control, whereas fenvalerate reduced the progeny by only 36.4%.     

几种杀虫剂对绵蚜天敌日光蜂成虫的影响

室内测定结果表明,杀虫剂啶虫咪对苹果绵蚜的天敌日光蜂蛹的羽化率、成虫的死亡率影响很小,对成虫的击倒率也低,属于2级微害产品;毒死蜱对蛹羽化率、成虫死亡率影响大,达到或接近4级有害产品标准;除虫菊和乙酰甲胺磷对日光蜂的毒性介于上述2种农药之间;印楝对蛹的羽化中度有害,但对成虫属微害。防治绵蚜要注意选用对日光蜂等天敌毒性较小的药剂。     

Laboratory and glasshouse screening of pesticides for adverse effects on the parasite Encarsia formosa gahan

Glasshouse screening of ten pesticides and the effect of water damping showed that all of the pesticides, with the possible exceptions of quinomethionate and heptenophos, were suitable for use in integrated control programmes involving Encarsia formosa. About 50 pesticides were screened in the laboratory for residual effects on adult E. formosa. They were grouped according to whether their effects were harmful, moderate or negligible. Acaricides, except quinomethionate, had negligible effects; fungicides generally had negligible effects though a few had moderate effects. Insecticides were equally divided between those which were harmful or moderate in effect. Individual examples are discussed more fully in relation to previous work and their commercial use in integrated control programmes. The two screening methods produced similar results though the laboratory method had the advantage of being much more rapid. Attention is drawn to the need for a simple test to identify pesticides having sublethal effects on natural enemies and for the standardisation of test methods.     

油菜根肿病的药剂防治及其保产效果试验分析

用敌磺钠、硫酸铜、多菌灵和代森锰锌4种杀菌剂不同浓度进行油菜根肿病防效试验.结果表明,4种药剂均有一定防病效果,尤以50%多菌灵WP的防效最好,且药剂浓度越高的防效越好,防效越好的油菜产量越高.药剂防病的保产作用,是发病株率减少和病株病情减轻的结果.     

6种农药对瓜蚜的毒力测定及田间药效

为了筛选防治西瓜瓜蚜的有效药剂,用6种药剂进行了室内毒力测定和田间药效试验。结果表明,1.8%阿维菌素EC对瓜蚜的毒力最高,60g/L乙基多杀菌素SC毒力最低,48hLC50分别为0.38mg/L和2 225.63mg/L。6种药剂毒力大小依次为阿维菌素溴氰虫酰胺氟啶虫胺腈啶虫脒吡虫啉乙基多杀菌素。田间试验结果表明,1.8%阿维菌素EC 3 000倍、10%溴氰虫酰胺OD 2 000倍、22%氟啶虫胺腈SC 4 000倍对瓜蚜速效性及持效性均较好,3~14d防效均达到90%以上,防效差异不显著;20%啶虫脒WP 3 000倍和10%吡虫啉WP 3 000倍速效性及持效性均较差,1d防效分别为31.31%和6.66%,14d防效分别为57.39%和47.80%;60g/L乙基多杀菌素SC 1 000倍防效最差,药后14d的最高防效仅为34.70%。推荐田间轮换使用阿维菌素、溴氰虫酰胺、氟啶虫胺腈防治瓜蚜。     

农药对生物多样性的负面影响及其对策

本文从基因、物种、生态系统三个水平上阐述了农药对生物多样性的影响，并提出了解决的对策。     

甲基毒死蜱和乙基毒死蜱对斜纹夜蛾、菜粉蝶幼虫毒力测定及药效试验

测定了甲基毒死蜱原药和乙基毒死蜱原药对斜纹夜蛾、菜粉蝶幼虫的毒杀活性及15％甲基毒死蜱乳油和15％乙基毒死蜱乳油对斜纹夜蛾幼虫的盆栽防效。室内结果表明,处理后24 h,甲基毒死埤和乙基毒死蜱对斜纹夜蛾2龄幼虫的LC₅₀值分别为16.11 mg／L和7.28 mg／L;48 h后,LC₅₀值分别为6.941 mg／L和4.06 mg／L。处理24 h,甲基毒死蜱和乙基毒死蜱对菜粉蝶3龄幼虫LC₅₀值分别为2.29 mg／L和1.38 mg／L;48 h后,LC₅₀值分别为0.42 mg／和0.90 mg／L。盆栽试验表明,药后1、3、5 d,15％甲基毒死蜱乳油1 000倍液对斜纹夜蛾幼虫的防效分别为76.92％、92.11％和94.29％;15％乙基毒死蜱乳油1 000倍液防效分别为87.18％、92.11％和97.14％。