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1.
棉铃虫Bt抗性种群的RAPD-PCR初步分析   总被引:5,自引:0,他引:5  
经室内筛选获得了棉铃虫对Bt杀虫剂、Bt毒蛋白和转Bt基因棉的抗性种群。利用RAPD技术 ,成功地扩增得到 105条多态性条带 ,经过聚类分析发现 ,棉铃虫对Bt产生抗性后在基因水平发生了变异。RAPD技术不仅可以用来鉴定棉铃虫对Bt是否产生抗性 ,而且可以区分不同的Bt抗性种群  相似文献   

2.
棉铃虫Helicoverpa armigera是一种全球性的重要农业害虫,主要为害棉花、玉米和大豆等作物。长期种植单价Bt棉花(表达Cry1Ac蛋白)会使棉铃虫田间种群承受单一、持续的选择压力,必然会导致棉铃虫对Cry1Ac的抗性发生演化。该文概述我国棉铃虫田间种群对Cry1Ac的抗性现状、自然庇护所对棉铃虫Cry1Ac抗性演化的延缓作用以及棉铃虫对Cry1Ac抗性的遗传多样性,并对今后我国关于棉铃虫Bt抗性的治理对策进行了展望。  相似文献   

3.
为明确全球气候变暖对不同寄主植物上棉铃虫Helicoverpa armigera种群发生的影响,通过收集2008—2019年全国范围、华北地区、华东地区、西北地区及华中地区7种寄主植物(小麦、玉米、大豆、棉花、花生、蔬菜和其他粮食作物)上棉铃虫成灾面积及各地区平均温度数据,采用单因素方差分析法及广义线性模型分析不同寄主植物上棉铃虫种群的发生程度。结果显示,玉米、大豆、花生和蔬菜寄主植物上棉铃虫成灾面积显著增加,棉花上棉铃虫成灾面积显著降低。玉米(全国范围、华北地区)、花生(全国范围、华中地区)及蔬菜(华东地区)上棉铃虫成灾面积随着温度距平的升高而显著增加;但棉花上棉铃虫成灾面积随着温度距平的升高而显著降低。如全国范围内,在玉米和花生上,2014—2019年棉铃虫成灾面积均显著高于2008—2013年,其增加比率分别为24.0%和34.3%;在棉花上,2014—2019年棉铃虫成灾面积显著低于2008—2013年,其降低比率为62.0%。表明全球气候变暖显著增加了玉米、花生及蔬菜上棉铃虫成灾面积,而棉花上棉铃虫成灾面积的降低主要受转Bt基因棉花种植的影响。  相似文献   

4.
In Africa, Helicoverpa armigera (Hübner) (Lepidoptera, Noctuidae) is a key pest of cotton and vegetable crops, particularly tomato. Alternatives to insecticides to control this pest are needed such as conservation biological control. However, knowledge on the diversity and ecology of naturally occurring enemies of H. armigera is limited. A two-year field survey was conducted in a set of tomato farmer fields in the main vegetable-growing area in Senegal (Niayes) to assess the spatial and seasonal occurrence of indigenous parasitoids of H. armigera, and to evaluate the effect of insecticide use on biological control efficiency. No parasitoid emerged from H. armigera eggs. Incidence of larval parasitoids was generally moderate (20%) but highly variable (0%–100%) among fields, independently of host abundance, and negatively affected by the number of insecticide applications. Larval parasitism was largely dominated by the larval parasitoid Meteorus laphygmarum Brues (Hymenoptera, Braconidae), but a positive correlation was found between specific richness or Shannon diversity index of the parasitoid community and parasitism rate. This study is a first step toward development of research and extension programs for conservation of natural enemies in the framework of integrated management of the tomato fruitworm in Senegal.  相似文献   

5.
The combined action of pyrethroids plus organophosphates was assessed on putatively resistant field populations of Helicoverpa armigera from Pakistan by using a leaf-dip bioassay. Ethion showed a good potentiation with bifenthrin, lambdacyhalothrin, cyfluthrin, betacyfluthrin, fenpropathrin, esfenvalerate, fluvalenate and tralomethrin. Profenofos was potentiating with bifenthrin but additive with lambdacyhalothrin. Methyl parathion also exhibited potentiation with bifenthrin. Contrarily, quinalphos produced an antagonism with bifenthrin. Chlorpyrifos potentiated lambdacyhalothrin in one population but had an additive effect in the other. A strong potentiation of pyrethroids by ethion in some populations indicates that esteratic detoxification is a key mechanism involved in imparting resistance to pyrethroids in Pakistani H. armigera.  相似文献   

6.
We determined the effects of petroleum spray oil (PSO) (Caltex Canopy®) on oviposition responses of Helicoverpa armigera Hubner and Ostrinia nubilalis Hubner adults, and larval survival of the pest moths on cotton and maize plants in the laboratory. Application of 2% (v/v) of the PSO deterred H. armigera oviposition. Increasing the rate from 2 to 5% (v/v) did not significantly reduce the number of eggs laid by H. armigera on the treated plants. In contrast, the minimum rate at which the oil could deter oviposition of O. nubilalis on maize plants was 5% (v/v). Increasing the rate from 5 to 10% (v/v) did not significantly reduce the number of eggs laid per plant. However, a reduction in the rate of the PSO from 5 to 3% (v/v) resulted in a 73.9% increase in oviposition activity on the maize plants. In wind tunnel bioassay tests, all mated H. armigera females tested could detect and settle on plants treated with water but with plants treated with PSO at various times, only 50% of tested females settled on the plants 4?–?5 days after treatment (DAT) and none on the plants 0?–?2 DAT. A solid phase micro-extraction (SPME) test to determine the effect of the PSO on volatiles released by the cotton plants showed that the quantity of volatiles released by the cotton plants treated with PSO was lower than for water treated plants. This indicates that the PSO sprays may be suppressing or masking the leaf surface volatiles of the cotton plants, thereby deterring oviposition of H. armigera. Larval survival data show that PSO sprays can cause direct mortality of first, second and third instar O. nubilalis larvae. PSOs may have the potential to be integrated into pest management programme targeting H. armigera and O. nubilalis on cotton and maize crops, respectively.  相似文献   

7.
Insecticide resistance inHelicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is one of the most important constraints on cotton production in Turkey. We investigated the susceptibility ofH. armigera strains collected from cotton fields in the Adana, Hatay and Antalya provinces to insecticides which are in wide use. LD50 values for tralomethrin, lambda-cyhalothrin, endosulfan, profenofos and methomyl were determined by topical bioassay. At the LD50 levels, resistance ratios for tralomethrin were 24.7-, 19.7- and 15.7-fold in the Adana, Hatay, and Antalya strains, respectively; and for lambda-cyhalothrin were 41-, 20-and 40-fold, respectively. Resistance ratios ranged from 1.2- to 2.1-fold in all field strains for endosulfan, profenofos and methomyl, with no significant resistance. These results suggest the presence of resistance to tralomethrin and lambda-cyhalothrin inH. armigera strains collected from cotton fields, but no resistance to endosulfan, profenofos or methomyl could be observed.  相似文献   

8.
Pupation of cotton bollworm, Helicoverpa armigera (Hübner), occurs in the soil. This may be a weak link in the life-cycle, exploitable through cultivation, in the control of this important pest. We evaluated the effects of irrigation on the performance of H. armigera. It did not affect the numbers of larvae entering the soil. However, irrigation treatments made on the 2nd, 3rd and 10th day after larvae entered the soil significantly reduced moth emergence (27, 19 and 28.7% emerged from the respective treatments, compared to 93.7% emerging from the control). Irrigation did not affect the time taken from the larva entering the soil to female adult emergence, but it significantly delayed the time in males. Realized fecundity of the emerging H. armigera adults was significantly decreased by irrigation treatment, especially on the 10th day, with a mean of only 367 eggs laid per female. Irrigation after larvae entered the soil substantially decreased survival of H. armigera, and the increase in the size of the generation following irrigation was only 2.8 times for the irrigation treatments on the 3rd and 10th day after larva entered the soil, respectively, compared with that of the control treatment. We suggest utilizing irrigation practices to suppress overwintering pupal numbers, in order to control the spring generation of H. armigera.  相似文献   

9.
Helicoverpa armigera collected from cotton growing areas of South Sulawesi, Indonesia in 1987 and early 1988 were resistant to cypermethrin. It is suggested that the 86-fold resistance to cis-cypermethrin in 1987 and the 65-fold resistance to cis/trans-cypermethrin in 1988 are consistent with this being a major cause of failure to control the insects in cotton in this area. The second laboratory generation showed a 20-fold resistance to fenvalerate. The larvae collected in 1988 additionally had a 203-fold resistance to DDT and a 5.6-fold resistance to endosulfan. The results are discussed in relation to the fact that this is a further region in which Helicoverpa armigera has developed resistance to a number of pyrethroids.  相似文献   

10.
为明确棉铃虫Helicoverpa armigera ATP结合盒转运蛋白家族A蛋白亚家族2(ATP binding cassette transporter subfamily A member 2,ABCA2)在Cry2Ab杀虫机制中的作用,利用酵母双杂交技术研究棉铃虫ABCA2与Cry2Ab的结合特性,并利用RNA干涉(dsRNA和siRNA)降低ABCA2在细胞和幼虫中的表达,结合细胞毒理学试验分析ABCA2的功能。结果表明,棉铃虫ABCA2能与Cry2Ab特异性结合;棉铃虫的ABCA2序列与美洲棉铃虫H.zea相关序列的相似度为92.86%,利用dsRNA干涉美洲棉铃虫中肠细胞ABCA2的表达能显著降低Cry2Ab对中肠细胞的毒力;利用siRNA干涉技术降低ABCA2在棉铃虫幼虫活体中的表达也显著降低了Cry2Ab对幼虫的毒力。表明棉铃虫ABCA2不仅是Cry2Ab的特异性结合蛋白,而且参与Cry2Ab的杀虫过程,是Cry2Ab的一个重要功能受体。  相似文献   

11.
为明确寄生蜂中红侧沟茧蜂Microplitis mediator与核型多角体病毒(nucleopolyhedrovirus,NPV)对寄主棉铃虫Helicoverpa armigera的联合效应,测量中红侧沟茧蜂和NPV单处理及复合处理后棉铃虫幼虫的形态学指标,并统计棉铃虫幼虫死亡率及寄生蜂中红侧沟茧蜂子代存活率。结果显示,处理3 d和5 d后,中红侧沟茧蜂和NPV单处理及复合处理的棉铃虫幼虫体长、体宽、头壳宽度、体重均显著低于对照,但各处理之间差异不显著。接入浓度为2.5×104 OBs/mL和2.5×106 OBs/mL NPV时,中红侧沟茧蜂和NPV这2种生防因子对棉铃虫均表现为拮抗效应或累加效应。接入浓度为2.5×104 OBs/mL NPV时,先寄生后接毒和先接毒后寄生处理的棉铃虫实际死亡率分别为4.35%和14.26%;接入浓度为2.5×106 OBs/mL NPV时,棉铃虫实际死亡率则分别为31.55%和94.19%,先接毒后寄生处理的棉铃虫实际死亡率均显著高于先寄生后接毒处理的实际死亡率。接入浓度为2.5×106 OBs/mL NPV时,先寄生后接毒和先接毒后寄生处理的寄生蜂子代存活率分别为54.51%和3.71%,前者显著高于后者。表明中红侧沟茧蜂寄生和NPV侵染均能显著抑制棉铃虫的生长发育,但两者联合应用时拮抗效应明显且对寄生蜂子代有影响,同时用于生物防治棉铃虫时应谨慎。  相似文献   

12.
The pod borer Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is an important insect pest of chickpea and several other crops in Asia, Africa and Australia. The present studies were carried out on integration of various practices for the management of H. armigera in Punjab, Pakistan, during 2004-05. Chickpea variety ‘CM-2000’ was selected for evaluating various strategies such as cultural, mechanical, biological, microbial, and chemical control, individually and in various possible combinations, for the management of H. armigera at three different locations. Integration of weeding, hand picking and indoxacarb (an oxadiazine insecticide) proved to be the most effective in reducing the larval population and pod infestation and resulted in the maximum grain yield. The larval population of the combined effect of these practices was not significantly different from hand picking + indoxacarb, weeding + indoxacarb, and indoxacarb alone. Hand picking in combination with Bacillus thuringiensis, and weeding + hand picking, also controlled the larval population significantly, but was inferior to the above treatments. The release of Trichogramma chilonis Ishii (Hymenoptera: Trichogrammatidae) did not control H. armigera. It was concluded on the basis of the cost — benefit ratio that hand picking was the most cost-effective method for the control of H. armigera, while the maximum increase in grain yield was obtained in plots with weeding, hand picking, and indoxacarb.  相似文献   

13.

Studies were conducted at the Texas Agricultural Experiment Station research farms located at Munday (1996 test) and Chillicothe (1997 test) to evaluate relay strip crops in combination with a food spray to enhance biological control of bollworms, Helicoverpa zea (Boddie), and cotton aphids, Aphis gossypii Glover, in cotton. The relay crops included fall plantings of hairy vetch, Vicia villosa Roth, and canola, Brassica napus L., and a spring planting of grain sorghum, Sorghum bicolor L. Cotton, Gossypium hirsutum L., was planted between the relay crops or was isolated from the relay crops. Treatments within the two cotton systems included an untreated check plot, a plot sprayed with sugar+yeast (food spray) during summer to attract and hold predator insects, a plot sprayed with biological ('soft') insecticides for bollworm and cotton aphid control (Bacillus thuringiensis and pymetrozine, respectively), and a plot sprayed with harsh insecticides for bollworm and cotton aphid control (zeta cypermethrin and dicrotophos or profonofos, respectively). A split-plot experimental design, with three replications, was used where whole plots included relay and isolated cotton systems and subplots were the four food/chemical treatments. Predator numbers were monitored with a vacuum sampler once a week in relay crops and cotton. Bollworms and cotton aphids were monitored visually once a week in cotton during July and August. Total predator numbers were higher in cotton adjacent to relay crops in 1996, but not in 1997. The food spray did not enhance attraction and retention of predators either year. Bollworm larval numbers were significantly higher in relay cotton, food spray plots in 1996. Bollworm larval numbers were similar in relay and isolated cotton, and larval numbers were significantly reduced only in the plot where zeta cypermethrin (harsh insecticide plot) was used. In 1996, cotton aphid numbers in the relay cotton system were significantly higher in the untreated check plots in relation to numbers in the food spray, soft insecticide, and harsh insecticide plots, which were statistically similar. In the isolated cotton system, aphid numbers were highest in untreated plots, intermediate in food spray and soft insecticide plots, and lowest in the harsh insecticide plots. Aphid numbers increased more rapidly in the harsh insecticide plots that had been treated previously for bollworm control. The food spray and pymetrozine treatments reduced cotton aphids more effectively in the relay cropping system than in the isolated cotton system. Bollworms and cotton aphids did not reach pest status in 1997. The combination of a relay cropping system with a food spray did not enhance predator numbers and did not aid in retention of predators in cotton during August. Sucrose in the food spray attracted high numbers of bollworms in 1996.  相似文献   

14.
Organophosphates are valuable insecticides used to control Helicoverpa armigera on cotton in Australia. Those most commonly used for Helicoverpa spp. control are pro-fenofos, parathion-methyl and chlorpyrifos. However, there is an emerging organophosphate-resistance threat in Australian H. armigera, which is compounded by cross-resistance between profenofos and parathion-methyl. An insensitive acetylcholinesterase has been identified as the common resistance mechanism. No resistance to chlorpyrifos has been detected and acetylcholinesterase remains fully sensitive to the chlorpyrifos oxon. © 1998 Society of Chemical Industry  相似文献   

15.
棉铃虫Helicoverpa armigera是一种世界性分布的重大杂食性农业害虫,长期大量使用化学药剂防治棉铃虫导致其对不同种类杀虫剂产生了抗性。抗性分子机制的阐明有利于棉铃虫的科学防控和抗性治理。该文主要综述棉铃虫对化学杀虫剂的抗性发展现状,以及近年来棉铃虫抗药性分子机制的研究进展,包括解毒酶代谢能力增强、靶标敏感性降低和表皮穿透能力下降等方面,并就未来研究工作和棉铃虫抗性治理新技术进行了展望。  相似文献   

16.
We studied the effects of feeding on different cotton cultivars with different gossypol contents on the development, reproduction and food plant utilization of three successive generations of Cotton Bollworm, Helicoverpa armigera (Hübner). Significantly higher larval survival rates were observed in three successive generations of H. armigera fed on cotton cultivar “ZMS13”compared with cultivars “M9101” and “HZ401”. There was a significant decrease in fecundity in the first generation compared with the second and third generations of cotton bollworms fed on “M9101” and “ZMS13”. Cotton bollworm generation significantly influenced mean relative growth rate, relative growth rate and relative consumption rate. The relative growth rate significantly decreased in three successive generations of H. armigera fed on the high-gossypol cultivar “M9101” compared with those fed on low-gossypol cultivar “ZMS13”. However, a significantly higher relative growth rate was recorded in the third generation than in the first generation fed on “M9101”. Measurements of development and food utilization at the individual and population levels over more than one generation ought to provide a more meaningful prediction of long-term and population dynamics of the cotton bollworm.  相似文献   

17.
棉铃虫核多角体病毒的生产方法及其在生物防治中的应用   总被引:4,自引:0,他引:4  
本文是报道棉铃虫Heliothis armigera核多角体病毒(NPV)的生产方法及其在棉田应用的试验研究结果。NPV用棉铃虫幼虫生产。从虫卵接种开始,用人工饲料饲养棉铃虫幼虫,到四龄用病毒感染,六天后收集病死虫,病毒致死率80~85%,单虫含量4~6×10~9PIB。由棉饼粉、粗棉油等配制成诱饵加低剂量西维因作病毒增效剂与NPV混用,显著提高病毒的防治效果。四年田间试验表明,NPV杀虫剂防治棉铃虫的效果相当于或优于常用高效化学农药。1979年开展了大面积飞机微量喷雾PVN杀虫剂的试验,也取得了比较好的防治效果。  相似文献   

18.

The incidence levels of moths and larvae of Etiella zinckenella were studied in the reproductive stage of soybean at eight farmers' field sites. A positive relationship was found between moths, caught by sweeping during flowering and pod-formation, and seed damage. Hence, rough predictions of damage can be made based on moth catches. Damage incidence was recorded in unsprayed plots and in plots sprayed with deltamethrin during flowering and pod-formation. Spraying did not affect the densities of moths and larvae or damage to pods and seeds. Larvae of H. armigera, Spodoptera litura and Plusiinae were not affected by spraying, but the pod-sucking bug Riptorus linearis, and two groups of predators, spiders and coccinellids, were reduced.  相似文献   

19.
BACKGROUND: Studies were conducted on experimental cabbage plantings in 2009 and on experimental and commercial plantings in 2010, comparing farmers' current chemical standard pesticide practices with an integrated pest management (IPM) program based on the use of neem (Aza‐Direct) and DiPel (Bacillus thuringiensis). In experimental plantings, the IPM program used six or eight applications of neem and DiPel on a rotational basis. The standard‐practice treatments consisted of six or eight applications of carbaryl and malathion or control treatment. RESULTS: The IPM treatments reduced pest populations and damage, resulting in a better yield than with the standard chemical or control treatment. When IPM treatment included three applications of neem plus three applications of DiPel (on a rotational basis in experimental fields), it again reduced the pest population and damage and produced a better yield than the standard practice. The lower input costs of the IPM program resulted in better economic returns in both trials. CONCLUSIONS: The IPM components neem and DiPel are suitable for use in an IPM program for managing insect pests on cabbage (Brassica spp.). Copyright © 2011 Society of Chemical Industry  相似文献   

20.
棉铃虫对常见化学农药的触角电位反应   总被引:1,自引:0,他引:1  
利用电生理技术测定了棉铃虫对 15种常见农药的触角电位反应 (EAG) ,发现棉铃虫对不同农药品种的EAG反应差异很大 ,并且雌、雄蛾对某些农药品种的EAG反应截然不同 ,存在较大的性别差异。以上结果可为棉田害虫防治有选择地使用化学农药提供部分依据  相似文献   

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