核型多角体病毒感染对棉铃虫幼虫同类相残行为的影响

在室内研究核型多角体病毒（HaSNPV）感染对棉铃虫Helicoverpa armigera（Htibner）幼虫同类相残行为的影响。结果显示：感病棉铃虫随感病程度的加重,越容易被健康棉铃虫残食,而自然死亡的感病棉铃虫、冻死的感病棉铃虫和冻死的健康棉铃虫三者被健康棉铃虫残食的百分率无显著差异。表明感病棉铃虫和病虫尸体更易于被健康棉铃虫残食,是由于棉铃虫体力减弱而失去反击能力,不是由于病毒本身的影响。以健康棉铃虫、感病棉铃虫为残食者,冻死的病虫为被残食者,相残率无显著差异,表明病毒并未改变棉铃虫残食同类的天性。残食病虫的健康棉铃虫的化蛹率和羽化率均低于正常的健康棉铃虫,残食者为相残行为付出了很高的代价。     

Bt棉花对棉铃虫幼虫选择性行为的影响

利用“H”型嗅觉仪测定结果表明 :在棉花蕾期、花铃期 ,棉铃虫 2龄幼虫对常规棉的棉叶、嫩头的选择性明显高于转基因棉花品种 ,差异达显著或极显著水平。但 3龄幼虫对两者的选择性差异并不显著 ;而在棉花蕾期 ,果枝对棉铃虫 2龄幼虫选择性行为有一定的影响。试验初步说明Bt棉对棉铃虫低龄幼虫有一定的忌避作用 ,而对高龄幼虫忌避效应不显著。     

Feeding behaviour of Helicoverpa armigera larvae on insect-resistant transgenic cotton and non-transgenic cotton

Abstract: Feeding behaviour of Helicoverpa armigera Hübner (Lep.; Noctuidae) larvae on non‐transgenic Bacillus thuringiensis (Bt) cotton (Gossypium hirsutum L.), Zhong 30, and transgenic cowpea trypsin inhibitor (CpTI)‐Bt cotton, SGK 321, and non‐transgenic cotton, Shiyuan 321, was investigated in both choice tests and no‐choice tests. The results of choice tests suggested that neonates have the ability to detect and avoid transgenic cotton. In the choice tests of neonates with both transgenic and non‐transgenic cotton leaves, a significantly greater proportion of larvae and higher consumption were observed on non‐transgenic cotton than on the transgenic Bt or CpTI‐Bt cotton. In the choice tests with leaves of two transgenic cotton lines, the proportion of neonates on leaf discs of the two lines was not significantly different, but there was significantly higher consumption on CpTI‐Bt transgenic cotton than that on Bt transgenic cotton. In addition, significantly more neonates were found away from the leaf discs, lower consumption and higher mortality were achieved in the choice test with two transgenic cotton leaves than in the choice tests containing non‐transgenic cotton leaves. Leaves and buds were examined in choice tests of fourth instars. It appeared that fourth instars were found in equal numbers on transgenic and non‐transgenic cotton, except when larvae were exposed to leaves for 3 h. However, the total consumption on transgenic cotton was lower than that of the non‐transgenic cotton, so fourth instars may still have the capacity to detect transgenic cotton and reduce feeding on it, although they showed no preference on either transgenic or non‐transgenic cotton. More larvae were found off diet in the treatments with leaves than that of buds, and the number of injured leaf discs by per fourth instar was significantly higher than that of buds in choice tests, suggesting that leaf is a less preferred organ for H. armigera larvae, elicited more larval movements. Similarly, in no‐choice tests of fifth instars, significantly fewer feeding time and more moving time occurred on leaf than that of bud, boll and petal. When cotton line was considered, compared with non‐transgenic cotton, significantly lower feeding time and higher resting time occurred on the two transgenic cottons. Overall, H. armigera larvae have the ability to detect the transgenic Bt and CpTI‐Bt cottons or the less preferred organs and selectively feed more on the non‐transgenic cotton or the preferred organs, especially the neonates, which have a high capacity for avoiding transgenic cotton.     

Foraging behaviour of Helicoverpa armigera first instar larvae on crop plants of different developmental stages

Abstract:  Understanding how insect pests forage on their food plants can help optimize management strategies. Helicoverpa armigera (Hübner) (Lep., Noctuidae) is a major polyphagous pest of agricultural crops worldwide. The immature stages feed and forage on crops at all stages of plant development, damaging fruiting and non-fruiting structures, yet very little is known about the influence of host type or stage on the location and behaviour of larvae. Through semi-continuous observation, we evaluated the foraging (movement and feeding) behaviours of H. armigera first instar larvae as well as the proportion of time spent at key locations on mungbean [ Vigna radiata (L.) Wilczek] and pigeon pea [ Cajanus cajan (L.) Millspaugh] of differing developmental stages: seedling- and mature (flowering/pod fill)-stage plants. Both host type and age affected the behaviour of larvae. Larvae spent more time in the upper parts of mature plants than on seedlings and tended to stay at the top of mature plants if they moved there. This difference was greater in pigeon pea than in mungbean. The proportion of time allocated to feeding on different parts of a plant differed with host and age. More feeding occurred in the top of mature pigeon pea plants but did not differ between mature and seedling mungbean plants. The duration of key behaviours did not differ between plant ages in either crop type and was similar between hosts although resting bouts were substantially longer on mungbeans. Thus a polyphagous species such as H. armigera does not forage in equivalent ways on different hosts in the first instar stage.     

Field inactivation of wild-type and genetically modified Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus in cotton

Cotton bollworm (Helicoverpa armigera) is a serious pest on cotton in China. A specific baculovirus, H. armigera nucleopolyhedroviruses (HaSNPV) is used as a commercial biopesticide to control this pest. To improve the pesticidal properties, HaSNPV has been genetically engineered by both deleting the ecdysteroid UDP-glucosyltransferase (egt) gene from its genome (recombinant HaSNPV-EGTD) and incorporating an insect-selective toxin gene from the scorpion Androctonus australis (AaIT) (recombinant HaSNPV-AaIT). In the field, there was no significant difference among the inactivation rates of the two recombinant HaSNPVs and their parent wild-type, HaSNPV-WT. The inactivation rate of these viruses was significantly different in different years. The average half-life of HaSNPV was 0.57, 0.90 and 0.39 days in 2000, 2001 and 2002, respectively. Inactivation rates correlated well with solar radiation over these years.     

转双价基因抗虫棉及其杂交F1代对棉铃虫幼虫的抗性研究

利用室内生物测定法和田间调查法研究双价抗虫棉及其杂交F1代不同生育期主茎功能叶和花铃期不同组织器官的抗虫性。结果表明:双价抗虫棉及其杂交F1代的抗虫性变化规律与B t基因棉的抗虫性变化规律相近,为生育前期(苗期、蕾期)抗性强,生育后期(花铃期、吐絮期)抗性弱,在花铃期为:棉铃>棉蕾>花>棉叶,且差异极显著。与B t基因棉相比,生育前期双价抗虫棉及其杂交F1代的抗虫性略弱,但差异不显著;生育后期双价抗虫棉及其杂交F1代的抗虫性显著强于B t基因棉。     

中国各棉区棉铃虫滞育解除特点

试验研究了我国华南棉区、长江流域棉区、黄河流域棉区、北部特早熟棉区和西北内陆棉区棉铃虫Helicoverpa armigera(Hubner)13个地理种群的滞育解除特点。随纬度升高地理种群滞育蛹在高温下的发育时间显著延长,羽化格局趋于松散,在30℃下湖南衡阳种群和新疆哈密种群的发育时间分别为(15.6±4.9)d和(41.4±9.0)d。低温处理可明显降低长江流域以北种群的滞育历期,但对华南棉区北部种群则无明显的活化作用。湖南衡阳种群、湖北武穴种群、北京种群和新疆哈密种群活化滞育蛹的发育起点温度和有效积温分别为17.4℃和146.O日度,16.6℃和146.5日度,15.7℃和156.4日度及15.7℃和167.7日度。     

Effects of phenylacetaldehyde and (Z)-3-hexenyl acetate on male response to synthetic sex pheromone in Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

Abstract  The influence of two synthetic plant volatiles on the number of male Helicoverpa armigera (Hübner 1808) (Lepidoptera: Noctuidae) caught in sex pheromone-baited traps was studied in field plots in Australia. Phenylacetaldehyde and ( Z )-3-hexenyl acetate were combined with synthetic sex pheromone in traps. Generally, most males were captured in traps baited with pheromone alone and more males were captured by the mixture containing ( Z )-3 hexenyl acetate than that containing phenylacetaldehyde. At the three concentrations studied, neither volatile synergised the activity of the pheromone. Traps baited with the plant volatiles alone caught very few moths of either sex.     

不同地理飞蝗种群的遗传多样性

用GenBank中飞蝗Locusta migratoriaL.的序列来设计微卫星引物,并对这些引物的有效性进行验证。结果表明,在所设计的3对引物中,只有1对为有效引物,可扩增出微卫星位点。序列分析表明本位点是一个不连续的重复微卫星位点。该多态微卫星位点含有14个等位基因,不同飞蝗地理种群的等位基因数目、大小和频率都存在较大的差异。对该位点各等位基因型进行χ2检验,基因型频率的观察和期望杂合度分别为0.4578和0.8836,该位点不属于Hardy-Weinberg平衡位点(χ2=733.12,P=0.0000)。该微卫星位点表现出高度的多态性说明是分析飞蝗种群遗传多样性的优良分子遗传标记。     

转基因抗虫棉种植面积变化对花生田棉铃虫种群影响

【目的】棉铃虫Helicoverpa armigera(Hübner)是花生田主要害虫之一。转基因抗虫棉全面推广后,棉铃虫种群(包括棉田、花生田、玉米田)得到有效控制。近年,随着转基因抗虫棉种植面积逐年下降,花生田棉铃虫种群呈现逐年上升趋势。【方法】本文通过调查山东省花生主产区(非棉区)龙口、招远、莱阳、文登四个县级市花生田棉铃虫成虫、卵量、幼虫量等的发生情况,分析了棉铃虫发生面积及种群数量15年(2000—2014年)的变化规律,并重点分析了主要影响因素。【结果】结果表明:花生棉铃虫发生面积受棉花种植面积影响较大,二者呈显著负相关性;花生田棉铃虫累计诱蛾量总体呈下降趋势,但与棉花种植面积相关性不显著;棉铃虫卵量、虫量与抗虫棉种植面积呈显著负相关性。【结论】所以,转基因抗虫棉种植面积减少是导致花生田棉铃虫种群数量上升的主要因素。另外,近年玉米田棉铃虫发生面积也呈逐年上升趋势,与抗虫棉种植面积呈显著负相关。所以,随转基因抗虫棉种植面积的下降,若不采取有效措施,棉铃虫种群可能会出现大发生趋势。     

Effects of Bt-toxin Cry1Ac on Propylaea japonica Thunberg (Col., Coccinellidae) by feeding on Bt-treated Bt-resistant Helicoverpa armigera (Hübner) (Lep., Noctuidae) larvae

Abstract:  Propylaea japonica is an important predatory insect of common cotton pests. To assess the ecological effects of transgenic Bt cotton, expressing Cry1Ac toxin, on this predator, we examined the life history parameters of P. japonica for two generations by feeding them with Bt-resistant Helicoverpa armigera . After ingesting Bt-treated Bt-resistant H. armigera larvae in the third and fourth instar, the body mass and body length of adult P. japonica decreased, a combined effect of poor prey quality and Cry1Ac Bt-toxin may account for these effects. However, larval survivorship and development in these two instars, pupal mortality, fecundity and adult longevity of P. japonica were not affected in both the generations. These results suggest that ingesting Bt-toxin Cry1Ac-treated pests in advanced larval stage might have no significant effect on the fitness of predator P. japonica .     

Effect of weather factors on populations of Helicoverpa armigera moths at cotton-based agro-ecological sites

Pheromone trapping was used to monitor populations of the moth Helicoverpa armigera at five cotton‐based agro‐ecological sites – river, vegetable, orchard, forest and clean cultivation (areas under only cotton cultivation) – in the Bahawalpur district, Pakistan. Three locations at each site were chosen and three pheromone traps at each location were installed in cotton fields. Moth catches were recorded at 15–20 day intervals from 24 October 2004 to 19 December 2006. In 2004, the river sites showed the maximum trapped population of H. armigera (0.22/trap) followed by 0.165 per trap at the vegetable sites. Orchard, clean cultivation and forest sites had zero moth catches. In 2005, the river sites again showed the highest trapped population (0.57/trap), followed by clean cultivation (0.45/trap), vegetable (0.44/trap), orchard (0.40/trap) and forest (0.29/trap). The moths appeared during July to December and March to May. In 2006, sites showed non‐significant difference, with a population range of 0.47 to 0.97 moths per trap. On average, river sites peaked at 0.49 per trap, followed by vegetable (0.38), clean cultivation (0.47), orchard (0.35) and forest (0.25) sites. The peak was observed on 3 April 2006, and moths appeared during February to July and October to December. The minimum temperature in river, forest and clean cultivation sites; the maximum temperature in orchard sites; and the average temperature in river, orchard, forest and clean cultivation sites showed significant positive correlations with trapped moth populations. Relative humidity showed significant negative correlation with population at the orchard sites in 2005. All weather factors during 2004 and 2006 showed non‐significant correlations with the moth populations. No model was found to be best fit by multiple linear regression analysis; however, relative humidity, minimum temperature, maximum temperature, minimum temperature and maximum temperature contributed 8.40, 10.23, 2.43, 4.53 and 2.53% to the population fluctuation of the moth at river, vegetable, orchard, forest and clean cultivation sites, respectively.     

Learning in the nectar foraging behaviour of Helicoverpa armigera

Abstract .1. Learning may enable insects to obtain nectar from flowers more efficiently. Learning in nectar foraging has been shown primarily in studies of bees and butterflies. Here, learning is demonstrated in the nectar foraging behaviour of a noctuid moth, Helicoverpa armigera .
2. The present studies show that: (1) previous experience with a flowering host species increases the probability of that species being selected for nectar foraging, and (2) previous experience of a particular flower type (food source at bottom or top of the corolla tube) increases the likelihood of the food source being found when that flower type is being searched.
3. The implications of these findings for understanding the pattern of oviposition observed in wild populations of this important pest species are discussed.     

The combined effect of photoperiod and temperature on the calling behaviour of the true army worm, Pseudaletia unipuncta

ABSTRACT. Pseudaletia unipuncta (Haw.) (Lepidoptera: Noctuidae) virgin females, maintained at either 10 or 25d?C under LD 12:12 or 16:8 h, started calling at different ages. For a given photoperiod, calling was initiated 11 days later at 10d?C than at 25d?C, while for a given temperature, calling at LD 12:12 h was 3–4 days later than at LD 16:8 h. At 10d?C 50.8% of females did not call within 35 days at LD 12:12 h compared with 30.8% at LD 16:8 h. Calling started earlier in the scotophase at 10d?C than at 25d?C and at LD 16:8 h than at LD 12:12 h. Under all treatments calling generally advanced on successive nights. The time elapsed between the mean onset time of calling and the mid-scotophase was relatively constant under both photoperiod conditions at 25d?C, but at 10d?C was more variable. The mean time spent calling increased significantly with calling age but did not differ significantly between the four experimental conditions tested. Older (15 days) females transferred from 10d?C, LD 16:8 h to 25d?C at either LD 163 or 12:12 h, required less time to initiate calling than younger (5 days) ones. Those transferred from 10d?C, LD 12:12 h took the same time, regardless of their age at the time of the transfer. Females experiencing either a decrease or increase in daylength as well as a temperature increase, required respectively more or less time to initiate calling, compared with individuals that only experienced an increase in temperature. If temperature was the only parameter changed females that initiated calling soon after the transfer immediately adjusted their calling periodicity to prevailing conditions. When both temperature and photoperiod were altered, it took several days before calling periodicity adjusted to the new regime. The ecological implications of temperature and photoperiodic conditions on the possible autumn migration of P. unipuncta are discussed.     

西藏飞蝗九个地理种群群居型形态特征的数量分析

为探讨群居型西藏飞蝗Locusta migratoria tibetensis Chen地理种群数量性状关系,从青藏高原9个地区采集到不同地理种群,以数值分析对形态指标及其比值进行了分析。结果表明,前翅长度(E)、后足股节长度(F)、头宽(C)形态指标和E/F、F/C两个比值可以作为分析种群关系的参数。聚类分析和主成分分析结果相似,能够较好地说明青藏高原9个种群的地理变异和种群相互关系,9个地理种群可以分三个类群,即第Ⅰ类群包括百巴(BB)与八美(BM)种群;第Ⅱ类群包括普兰(PL)、扎囊(ZN)、洛须(LX)种群;第Ⅲ类群包括噶尔(GE)、香孜(XZ)、日土(RT)、那嘎(NG)种群。     

Biology of Campoletis chlorideae (Uchida) (Hym., Ichneumonidae) developing in Bt-treated, Bt-resistant Helicoverpa armigera (Hübner) (Lep., Noctuidae) larvae

Abstract:  Life history parameters in two generations of endoparasitoid Campoletis chlorideae (Uchida) were examined using Bacillus thuringiensis (Bt)-resistant Helicoverpa armigera (Hübner) larvae feeding on B. thuringiensis toxin Cry1Ac. In the laboratory, Bt toxin was fed to Bt-resistant host larvae continuously in case of Bt treatment and only before or after the host larvae were parasitized in Bt–P and P–Bt treatments, respectively. C. chlorideae pupae developed faster in Bt treatment than non-Bt treatment. The shortened pupal stage duration was mainly because of the feeding of host larvae on Bt-diet before being parasitized. Body length of adult male C. chlorideae developed inside Bt-treated Bt-resistant (Bt–Bt) H. armigera larvae significantly decreased, especially in host larvae feeding on Bt-diet after being parasitized. However, survival, pupal mortality and adult longevity of C. chlorideae were almost unaffected in Bt-resistant H. armigera larvae feeding on Bt-toxin. Furthermore, Bt-treated host larvae had the same effect on the F₁ progeny of C. chlorideae as the previous generation, and there was no significant difference between generations. This experiment suggests that there is very limited effect on the life history parameters in two generations of C. chlorideae parasitizing Bt–Bt H. armigera larvae. But both generations of C. chlorideae are affected when Bt-resistant H. armigera larvae fed on Bt toxin for different durations.     

Neurological influences on pheromone release and calling behaviour in the gypsy moth, Lymantria dispar

ABSTRACT. Surgical removal of the brain or disconnection of the last abdominal ganglion from the ventral nerve cord prevented sex pheromone release in female Lymantria dispar (L.) (Lymantriidae), as assayed by the male wing-fanning response. The calling behaviour continued to occur in individuals whose terminal abdominal ganglion had been thus isolated, however, indicating that the neural mechanisms controlling calling function independently in the last abdominal ganglion.     

Helicoverpa armigera baseline susceptibility to Bacillus thuringiensis Cry toxins and resistance management for Bt cotton in India

Transgenic cotton that produces insecticidal proteins from Bacillus thuringiensis (Bt), often referred to as Bt cotton, is widely grown in many countries. Bt cotton with a single cry1A gene and stacked also with cry2A gene has provided satisfactory protection against the damage by the lepidopteran bollworms, especially the cotton bollworm, Helicoverpa armigera (Hübner) which is considered as a key pest. The baseline susceptibility of the larvae of H. armigera to Cry1Ac and other toxins carried out in many countries has provided a basis for monitoring resistance. There is no evidence of development of field-level resistance in H. armigera leading to the failure of Bt cotton crop anywhere in the world, despite the fact that Bt cotton was grown on the largest ever area of 12.1 million hectares in 2006 and its cumulative cultivation over the last 11 years has surpassed the annual cotton area in the world. Nevertheless, the Bt resistance management has become a necessity to sustain Bt cotton and other transgenic crops in view of potential of the target insects to evolve Cry toxin resistance.     

不同地理种群大豆蚜生长发育的形态指标

对采自广东、山东、河北和黑龙江4个省份大豆蚜Aphis glycines Matsumura种群在不同温度条件下的生长发育形态指标进行测定。结果表明,在20、25和30℃,不同地理种群大豆蚜生长发育形态指标差异不显著;在15℃,不同地理种群大豆蚜生长发育形态指标差异显著。在15～30℃,单一大豆蚜地理种群形态指标有随温度降低而增大的趋势。试验结果也表明,单一地理种群大豆蚜的Q值也有随着温度降低而增大的趋势;而在相同温度下,不同种群间的Q值变化不明显,差异性不显著。