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排序方式: 共有333条查询结果,搜索用时 15 毫秒
51.
P. S. GREWAL P. N. RICHARDSON G. COLLINS R. N. EDMONDSON 《The Annals of applied biology》1992,121(3):511-520
In a mushroom crop (Agaricus bisporus) affected by a very low level of sciarid fly (Lycoriella auripila) infestation, the effects of an indigenous isolate of insect-parasitic nematode (Steinernema feltiae) and of two commonly used insecticides (diazinon and diflubenzuron) were studied. When compared with untreated plots, nematodes applied to the casing had no adverse effects on mushroom yields whereas insecticides decreased yields. At a rate of 3 × 106 infective juveniles per tray (surface area = 0.56 m2), S. feltiae elicited increases of 28.5% and 19% in the mean total numbers and weights of mushrooms respectively. Treatment only with diflubenzuron resulted in 14.6% and 6% reductions in mean total numbers and weights of mushrooms, respectively; treatment with both diazinon and diflubenzuron caused 18.5% and 9.4% losses. Application of nematodes generally reduced the mean weight per mushroom whereas insecticides increased it; nematodes delayed the onset of mushroom production (first flush) whereas diflubenzuron delayed the third and fourth flushes. Nematode contamination of sporophores was minimal when S. feltiae was applied at casing. Although their numbers declined with time, the nematodes persisted, in the casing layer, throughout the cropping period of seven weeks. It is concluded that yield benefits associated with nematode application can result mainly from nematode effects on A. bisporus and not solely from suppression of a damaging pest population. 相似文献
52.
The dominant bacteriaPseudomonas sp. andArthrobacter sp. were isolated from the standing water of carbofuran-retreatedAzolla plot.Arthrobacter sp. hydrolysed carbofuran added to the mineral salts medium as a sole source of carbon and nitrogen while no degradation occurred withPseudomonas sp. Interestingly, when the medium containing carbofuran was inoculated with bothArthrobacter sp. andPseudomonas sp., a synergistic increase in its hydrolysis and subsequent release of CO2 from the side chain was noticed. This synergistic interaction was better expressed at 25° C than at 35° C. Likewise, related carbamates, carbaryl, bendiocarb and carbosulfan were more rapidly degraded in the combined presence of both bacterial isolates. 相似文献
53.
亚洲小车蝗痘病毒与化学杀虫剂混用的杀虫效果及对寄主主要解毒酶活性的影响 总被引:1,自引:0,他引:1
亚洲小车蝗痘病毒(Oedaleus asiaticus entomopoxvirus, OaEPV)作为一种增效剂,分别与马拉硫磷、毒死蜱、高效氯氰菊酯、氟氯氰菊酯 、溴氰菊酯化学杀虫剂混合饲喂亚洲小车蝗若虫,统计致死中浓度 LC50 和其混合使用后的增效比;测定虫体内与抗性有关的两种重要酶——羧酸酯酶(CarE)和谷胱甘肽 S-转移酶(GSTs)的比活力。结果表明:OaEPV 与化学杀虫剂混合饲喂亚洲小车蝗,OaEPV 与毒死蜱 、高效氯氰菊酯、氟氯氰菊酯、溴氰菊酯混用对亚洲小车蝗无明显的增效作用,OaEPV 与马拉硫磷混用,具有一定的增效作用,增效比为 1.42 倍。混剂感染亚洲小车蝗,除与溴氰菊酯混用外,虫体的中肠部位 CarE 的比活力都受到了明显的抑制作用,其中 OaEPV 与马拉硫磷混用下降了 4.21 倍,抑制作用最大。当 OaEPV 与氟氯氰菊酯、溴氰菊酯化学杀虫剂混用后,中肠部位 GSTs 受到了明显的抑制作用,而其脂肪体部位 CarE 和 GSTs 的变化无一定的规律性。结果提示痘病毒与农药混合处理时,病毒主要通过抑制中肠部位 CarE 比活力而增加了农药的杀虫效果。 相似文献
54.
MA Schuler 《Molecular ecology》2012,21(17):4157-4159
55.
苯甲酰脲类杀虫剂对亚洲玉米螟生长发育和繁殖的效用 总被引:2,自引:0,他引:2
为全面评价苯甲酰脲类(BPUs)杀虫剂对亚洲玉米螟Ostrinia furnacalis(Guenée)的持续控制作用,采用叶片浸渍法,测定氟啶脲、除虫脲、氟铃脲和虱螨脲对亚洲玉米螟生长发育和繁殖的影响。结果表明,经4种BPUs处理后,亚洲玉米螟存活幼虫的历期延长了2.4~4.3d,平均单头雌、雄蛹重分别减轻了10.3~13.2mg和0~7.7mg,幼虫化蛹率和成虫交配成功率分别下降了14.1%~43.3%和5.6%~25.6%,产卵量降低了25.5%~53.3%,但卵孵化率没有明显改变。亚洲玉米螟雌、雄蛾吸食蔗糖水药液后,成虫寿命增加了1.3~4.3d,产卵量下降40.3%~58.2%,卵孵化率降低了32.9%~64.3%,F1代幼虫死亡率是对照组的3.5~8.5倍,表明苯甲酰脲类杀虫剂显著抑制了亚洲玉米螟幼虫生长发育和成虫的繁殖力。 相似文献
56.
57.
为了科学施药, 合理保护和利用天敌对棉铃虫Helicoverpa armigera进行综合防治, 本研究在室内测定和比较了复配杀虫剂BtA和7种常用杀虫剂(阿维菌素、 Bt、 β-氯氰菊酯、辛硫磷、定虫隆、氰戊菊酯和丁硫克百威)对棉铃虫的杀虫效果及对其天敌中红侧沟茧蜂Microplitis mediator蛹和雌成虫的触杀毒性。采用浸叶法测定杀虫剂在室内72 h内对棉铃虫3龄幼虫的杀虫效果, 结果表明: 与其他杀虫剂相比, BtA对棉铃虫幼虫具有更高的毒性和致死效应 (LC50=0.7364 mg/mL)。将棉铃虫3龄幼虫接到用浓度4 mg/mL上述杀虫剂分别处理过的大白菜上24, 48和72 h, 发现其死亡率之间存在显著差异(P≤0.05)。但在72 h后, BtA和其他杀虫剂对棉铃虫幼虫的杀虫效果之间并无显著差异(P>0.05)。BtA施药后, 随着时间的延长, 棉铃虫幼虫的死亡率也在增加。另外, 通过杀虫剂对寄生蜂中红侧沟茧蜂蛹和雌成虫的触杀毒性的生物测定发现: 与β-氯氰菊酯、 氰戊菊酯和丁硫克百威相比, BtA对中红侧沟茧蜂蛹和雌成虫的毒性较低, 对其蛹和雌成虫致死率分别仅为13.82%和7.33%。本研究证明BtA对鳞翅目害虫具有中等毒性, 而对寄生蜂中红侧沟茧蜂则具有较低毒性。 相似文献
58.
基因工程技术在降解农药中的应用 总被引:2,自引:2,他引:0
综述了基因重组、原生质体融合、外源基因、降解酶和固相反应器等基因工程技术在降解农药中的研究及应用进展,提出了几种高效降解农药的基因工程菌的构建策略和构建手段。 相似文献
59.
Efficacy of a fipronil bait in reducing the number of fleas (Oropsylla spp.) infesting wild black‐tailed prairie dogs 下载免费PDF全文
David M. Poché Daniel Hartman Larisa Polyakova Richard M. Poché 《Journal of vector ecology》2017,42(1):171-177
Bubonic plague (Yersinia pestis) is a deadly zoonosis with black‐tailed prairie dogs (Cynomys ludovicianus) as a reservoir host in the United States. Systemic insecticides are a promising means of controlling the vectors, Oropsylla spp. fleas, infesting these prairie dogs, subsequently disrupting the Y. pestis cycle. The objective of this study was to conduct a field trial evaluating the efficacy of a grain rodent bait containing fipronil (0.005%) against fleas infesting prairie dogs. The study was performed in Larimer County, CO, where bait was applied to a treatment area containing a dense prairie dog population, three times over a three‐week period. Prairie dogs were captured and combed for fleas during four study periods (pre‐, mid‐, 1st post‐, and 2nd post‐treatment). Results indicated the use of bait containing fipronil significantly reduced flea burden. The bait containing fipronil was determined to reduce the mean number of fleas per prairie dog >95% for a minimum of 52 days post‐initial treatment application and 31 days post‐final treatment application. These results suggest the potential for this form of treatment to reduce flea population density on prairie dogs, and subsequently plague transmission, among mammalian hosts across the United States and beyond. 相似文献
60.