虫害诱导的水稻挥发物对褐飞虱的驱避作用

水稻叶片在遭受害虫的危害时,释放一些特异性的挥发性物质。这些挥发性信息物质在调节植物、植食性昆虫及其天敌的相互关系中有重要作用。利用“Y”型嗅觉仪研究了褐飞虱对虫害诱导的11种水稻挥发物（浓度为2 Μl 化合物溶解在100 Μl丙酮溶液中）的行为反应。结果表明,(E)-2-己烯醛、(E)-2-己烯-1-醇、-2-庚醇和水杨酸甲酯等4种化合物对褐飞虱成虫有显著的驱避作用,而(Z)-3-己烯-1-醇、-2-庚酮、柠檬烯、罗勒烯、芳樟醇、-β-子丁香烯和橙花叔醇等7种物质对褐飞虱成虫的选择行为无显著影响。浓度梯度的实验表明,浓度(不同体积的待测化合物用100 Μl丙酮稀释)较低的(E)-2-己烯醛（0.5 Μl、1 Μl）和芳樟醇（05 Μl、1 Μl、5 Μl）对褐飞虱成虫的选择行为无显著影响,而较高浓度的(E)-2-己烯醛（5 Μl、10 Μl）和芳樟醇（10 Μl）对褐飞虱成虫均有明显的驱避作用。     

非嗜食植物中的昆虫产卵驱避物及其利用

产卵是植物性昆虫生命周期中的一个重要环节,它能反映昆虫与植物相互作用的某些特点以及植食性昆虫对植物利用的策略.植物中的驱避物质在调节昆虫产卵行为过程中起着十分重要的作用.大量研究结果表明:许多非嗜食植物含有对昆虫产卵有驱避作用的次生化合物.研究植物中的昆虫产卵驱避物质不仅能在理论上加深对植食性昆虫产卵机制,植食性昆虫与植物间的相互关系以及昆虫群落构建机制等的认识,同时在害虫综合治理中有广泛的应用前景.     

丹皮酚对马铃薯块茎蛾雌虫产卵选择及幼虫的忌避作用研究

为探讨丹皮酚对马铃薯块茎蛾Phthorimaea operculella(Zeller)行为的影响,采用室内生物测定法,研究了丹皮酚对马铃薯块茎蛾雌虫产卵选择及初孵幼虫、老熟幼虫的忌避作用.结果表明,丹皮酚对马铃薯块茎蛾雌虫产卵、初孵幼虫、老熟幼虫均有显著忌避作用:选择性产卵实验中,5 mg/mL丹皮酚溶液的忌避指数为...     

植物精油对荔枝蒂蛀虫的产卵驱避效果

在室内采用非选择性和选择性两种试验方法,测定了14种非寄主植物精油对荔枝蒂蛀虫的产卵驱避效果.结果表明,香紫苏油、肉桂油和香茅油对荔枝蒂蛀虫有很好的产卵驱避效果,其非选择性产卵驱避率(ODRn)达90%以上;而选择性产卵驱避率(ODR.)达80%以上.留兰香油对荔枝蒂蛀虫也有较好的产卵驱避效果,其ODRn和ODR.分别为89.19%和73.30%.     

薇甘菊精油化学成分及其对小菜蛾的驱避及产卵抑制作用(英文)

用四臂嗅觉仪测定了小菜蛾对薇甘菊挥发油、芋烯、α-松油烯、里哪醇、β-石竹烯、马鞭草烯酮6种挥发物嗅觉反应,在网室,比较了挥发油及5种挥发物对小菜蛾雌虫产卵的驱避效果。结果表明:薇甘菊挥发油不仅对小菜蛾成虫有明显的驱避作用,而且能显著地减少其成虫在寄主植物上的产卵量。薇甘菊挥发油所含的5种挥发性化合物中芋烯、α-松油烯和里哪醇表现出较强的驱避效果(流量为100-180mL/min)和产卵抑制作用(剂量为10-20μL/株),而小菜蛾对马鞭草烯酮和β-石竹烯的嗅觉反应以及小菜蛾在这两种化合物处理的寄主植物上的产卵量与对照相比无显著差异。     

山胡椒及其挥发物对马铃薯块茎蛾产卵选择的影响

【目的】为了确定山胡椒Lindera glauca(Sieb.Zuce)是否对马铃薯块茎蛾Phthorimaea operculella Zeller的产卵有驱避作用。【方法】利用选择性产卵试验方法在室内分别测定了山胡椒的完整果实、压碎果实、根以及不同浓度(0.25~4.0 g E/m L)的压碎山胡椒果实正己烷提取物对马铃薯块茎蛾产卵选择性的影响;在模拟仓库内测定了压碎的果实对其产卵的影响;进而在室内测定了柠檬醛、沉香醇、香叶醇和α-水芹烯不同浓度(0.00075~0.012 g/L)的溶液对其产卵选择性的影响。【结果】山胡椒完整果实、压碎果实、根在室内对马铃薯块茎蛾产卵具有驱避效果,其中压碎果实的产卵驱避效果最好,20 g压碎果实的产卵驱避率可达93.7%。山胡椒压碎果实正己烷提取物在0.5~4.0 g E/m L的浓度范围内随着浓度的升高,产卵驱避效果逐渐增强。在模拟仓库内20 g压碎的果实产卵驱避率是82.5%;0.003~0.012 g/L的柠檬醛,0.012 g/L沉香醇,0.00075~0.012 g/L的香叶醇,0.003~0.012 g/L的α-水芹烯对马铃薯块茎蛾产卵有显著的驱避效果。【结论】山胡椒及其挥发物对马铃薯块茎蛾产卵有驱避效果。     

虫害诱导植物挥发物(HIPVs)对植食性昆虫的行为调控

虫害诱导植物挥发物(herbivore induced plant volatiles,HIPVs)具有植物种类、品种、生育期和部位的特异性,也具有植食性昆虫种类、虫龄、为害程度、为害方式和其他一些环境因子的特异性。由于其释放量明显大于健康植株,因此更易被天敌、害虫以及邻近的植物等所利用,从而调节植物、植食性昆虫与天敌三者之间的相互作用关系,增强植物在自然界的生存竞争能力。本文对HIPVs在植食性昆虫寄主定位行为中的作用、HIPVs对植食性昆虫的种群调控功能及其应用现状2个方面加以综述,并在展望中对目前研究中存在的一些问题进行了探讨。     

甜菜夜蛾对不同寄主植物的产卵和取食选择

为了探讨甜菜夜蛾Spodoptera exigua对不同寄主植物的产卵选择及成虫产卵选择与幼虫取食选择间的关联度, 本研究选取玉米、豇豆、甘蓝、黄瓜、棉花、辣椒和番茄7种植物进行了选择性和非选择性实验研究, 并采用Y型嗅觉仪测定了成虫对其中3种寄主植物及其挥发物抽提物的趋性。结果表明：在田间非选择性实验中, 甜菜夜蛾在不同寄主植物上的落卵量依次为：玉米>辣椒>棉花>黄瓜、豇豆、番茄>甘蓝。Y型嗅觉仪的行为测定表明, 雌成虫对玉米及其挥发物抽提物的趋性最强, 黄瓜次之, 对甘蓝的趋性最弱, 这与雌虫的产卵选择性一致。不同龄期甜菜夜蛾幼虫对寄主植物的取食选择性有所不同, 且随观测时间的延长有所改变;低龄幼虫对豇豆、玉米和黄瓜的选择性较强, 对甘蓝、番茄、辣椒和棉花的取食选择性则较弱, 高龄幼虫对辣椒也具有较强的选择性;5龄幼虫对寄主植物的选择性不如低龄幼虫明显。结果显示, 甜菜夜蛾对不同寄主植物的产卵选择性显著不同, 植物抽提物在雌成虫的产卵选择中具有重要作用, 甜菜夜蛾对寄主植物的产卵选择性和幼虫取食选择性并不一致。     

虫害诱导的植物挥发物代谢调控机制研究进展

长期受自然界的非生物/生物侵害,植物逐步形成了复杂的防御机制,为防御植食性昆虫的为害,植物释放虫害诱导产生的挥发性化合物(herbivore-induced plant volatiles,HIPVs)。HIPVs是植物-植食性昆虫-天敌三级营养关系之间协同进化的结果。HIPVs的化学组分因植物、植食性昆虫种类的不同而有差异。生态系统中,HIPVs可在植物与节肢动物、植物与微生物、虫害植物与邻近的健康植物、或同一植株的受害和未受害部位间起作用,介导防御性反应。HIPVs作为寄主定位信号,在吸引捕食性、寄生性天敌过程中起着重要作用。HIPVs还可以作为植物间信息交流的工具,启动植株的防御反应而增强抗虫性。不论从生态学还是经济学角度来看,HIPVs对于农林生态系中害虫综合治理策略的完善具有重要意义。前期的研究在虫害诱导植物防御的化学生态学方面奠定了良好基础,目前更多的研究转向阐述虫害诱导植物抗性的分子机制。为了深入了解HIPVs的代谢调控机制,主要从以下几个方面进行了综述。因为植食性昆虫取食造成的植物损伤是与昆虫口腔分泌物共同作用的结果,所以首先阐述口腔分泌物在防御反应中的作用。挥发物诱导素volicitin和β-葡萄糖苷酶作为口腔分泌物的组分,是产生HIPVs的激发子,通过调节伤信号诱发HIPVs的释放。接着阐述了信号转导途径对HIPVs释放的调节作用,并讨论了不同信号途径之间的交互作用。就HIPVs的代谢过程而言,其过程受信号转导途径(包括茉莉酸、水杨酸、乙烯、过氧化氢信号途径)的调控,其中茉莉酸信号途径是诱发HIPVs释放的重要途径。基于前人的研究,综述了HIPVs的主要代谢过程及其过程中关键酶类的调控作用。文中的HIPVs主要包括萜烯类化合物、绿叶挥发物和莽草酸途径产生的芳香族化合物,如水杨酸甲酯和吲哚等。作为化学信号分子,这些化合物中的一部分还能激活邻近植物防御基因的表达。萜烯合酶是各种萜烯类化合物合成的关键酶类,脂氧合酶、过氧化氢裂解酶也是绿叶挥发物代谢途径中的研究热点,而苯丙氨酸裂解酶和水杨酸羧基甲基转移酶分别是合成水杨酸及其衍生物水杨酸甲酯的关键酶类。这些酶类的基因在转录水平上调控着HIPVs代谢途径。最后展望了HIPVs的研究前景。     

东莨菪内酯对朱砂叶螨的驱避和产卵抑制活性

本研究采用叶碟浸渍法测定了东莨菪内酯对朱砂叶螨Tetranychus cinnabarinus(Biosduvals)雌成螨的触杀活性,采用选择性的半叶法测定了驱避活性,同时采用非选择性的全叶法测定了产卵抑制活性。结果表明,东莨菪内酯对朱砂叶螨雌成螨具有较好的触杀活性,采用叶碟浸渍法处理48h后的LC50为0.297mg·mL-1,LC30为0.105mg·mL-1,LC10为0.023mg·mL-1。采用LC50、LC30和LC103个浓度的东莨菪内酯处理雌成螨后,发现东莨菪内酯对雌成螨没有表现出明显的驱避活性,处理区和对照区24h和48h的着螨率均为50%左右;采用LC50和LC102个浓度处理雌成螨后表现出了一定的产卵抑制活性,平均产卵抑制率分别为23.02%和13.23%,而LC30对雌成螨的产卵量表现出了促进作用,平均产卵抑制率为-8.25%,这可能是由于毒物兴奋效应所致。本研究旨在为东莨菪内酯的进一步开发和应用奠定理论基础。     

黄地老虎飞行能力研究

黄地老虎Agrotis segetum是一种重要的农业迁飞性害虫,研究飞行生物学对明确其迁飞机理有重要意义。本项研究利用昆虫飞行磨系统对黄地老虎的飞行能力进行了测定。对实验室种群飞行能力的测定结果表明:1日龄成虫的飞行能力最弱;3日龄飞行能力最强,其24 h平均飞行时间、平均飞行距离和平均飞行速率分别达到12.16±0.74 h、48.94±3.40 km和3.76±0.12 km/h。雌蛾与雄蛾间的各项飞行参数均无显著差异,但处女成虫平均飞行距离和平均飞行速率均显著高于已交配个体。对渤海湾野外迁飞种群飞行能力的测定显示,早季节北迁个体和晚季节回迁个体的平均飞行时间和平均飞行距离无显著差异,但皆显著低于实验室种群。黄地老虎具有较强的飞行能力,日龄和交配是影响其飞行能力的关键因素。     

Genetic similarity and distribution of cry genes of Bacillus thuringiensis pathogenic for Spodoptera exigua (Lepidoptera: Noctuidae) and Agrotis segetum (Lepidoptera: Noctuidae)

Crystals of Bacillus thuringiensis isolates, obtained from dead caterpillars, had potential toxicity against insects in the orders Diptera, Coleoptera, Hemiptera and Lepidoptera. Strain MPU B32b had the highest number and variety of cry genes and seemed to be the most interesting for further research on development as a novel biopesticide.     

Impact of Spodoptera littoralis (Boisd.) and Agrotis ipsilon (Hufn.) larval frass on oviposition of conspecific insects

Ethanolic extracts of larval frass of the cotton leaf worm and the black cutworm were prepared and tested to deter the eggs lay of the adults of the same insects. Two different types of food were used for larval feeding. Extracts fractions were identified using gas chromatography–mass spectrometry analysis. High concentrations were more deterrent to oviposition than low. Extracted frass of fed larvae on semi-artificial diet was more effective than others fed on natural host. Sensitivity of the black cutworm adult females to the cotton leaf worm frass extract was clearly observed at high tested concentration of L_1–3 and L₄ frass extracts which resulted completely oviposition deterrent. Several fatty acids were identified qualitatively and quantitatively in frass extracts of different larval instars of both target insects. Type and quantity of fatty acid depends mainly on larval food source and larval instar, except palmitic acid which recorded at all larval instars and food sources. Oleic acid and ethyl 9-hexadecaenoic acid were found when semi-artificial diet used as a food source while myrisitic acid was observed only in extracted frass of fed larvae on castor oil leaves.     

Biology of Cotesia ( = Apanteles) telengai (Hymenoptera: Braconidae) on its natural host Agrotis segetum (Lepidoptera: Noctuidae)

The host suitability of Agrotis segetum Denis & Schiff., A. ipsilon Hufn., Spodoptera littoralis Boisd, S. exigua Hub., Mythimna loreyi Duponchel and Mamestra oleracea L. for the gregarious braconid Cotesia ( = Apanteles) telengai Tobias was determined under laboratory conditions. The parasitoid only completed its development in larvae of A. segetum. The percentage of successfully parasitized larvae and the mean duration of C. telengai egg‐larval period were inversely related to the age of the host or host instar at parasitization. The mean number of parasitoids which emerged per parasitized larva was positively correlated with the larval age. The sex ratio was consistently high (ca. eight males to one female), independent of the host instar parasitized, as compared to 1:1 as observed frequently in field populations of this wasp. The females of C. telengai were active and produced offspring at temperatures of 15, 20, 25 and 30° C. However, the mean percentage of parasitized larvae increased from 13.1 to 72% and the mean progeny per parasitoid female increased from 14.7 to 129.4 parasitoids, both significant, when the experimental temperature was raised from 15 to 30°C, while their mean development time decreased from 75.5 to 19.2 days. At 25°C, the virgin and mated females continued oviposition until days 16 and 17, with a lifetime total of progeny of 397.6 (SD ±224.7) and 611.1 (SD± 128.8) parasitoids respectively, reaching a maximum of 64.3 and 99.2 on day 2 respectively.     

Comparative study on the susceptibility of cutworms (Lepidoptera: Noctuidae) to Agrotis segetum nucleopolyhedrovirus and Agrotis ipsilon nucleopolyhedrovirus

The common cutworm (Agrotis segetum) and the black cutworm (Agrotis ipsilon) are serious soil pests of many vegetable and field crops all over the world. We have demonstrated the cross-infectivity of two baculoviruses, A. segetum nucleopolyhedrovirus (AgseNPV) and A. ipsilon nucleopolyhedrovirus (AgipNPV) for these two insect pests. The susceptibility of A. segetum to AgipNPV was confirmed by DNA restriction endonuclease analyses of DNA isolated from virus harvested from infected A. segetum larvae. For an initial comparison of both viruses, partial polyhedrin sequences were amplified by PCR, cloned, and sequenced. Both viruses shared a very similar polyhedrin gene sequence resulting in only three amino acid substitutions. Phylogenetic analyses clearly demonstrated that both viruses belong to NPV group II and are most closely related to a clade consisting of Spodoptera exigua NPV, Spodoptera frugiperda NPV, and Spodoptera littoralis NPV. Since AgipNPV shows high virulence for both cutworm species, it appears to be a suitable candidate as a single biological control agent of A. segetum and A. ipsilon.     

Mating Behavior and Reproductive Potential in the Turnip Moth Agrotis segetum (Lepidoptera: Noctuidae)

We investigated the lifetime mating potential and the reproductive behavior of male and female turnip moths Agrotis segetum (Schiff.) under field and laboratory conditions. The sex ratio was 1 : 1 in a lab-reared population as well as in two wild populations. Males were capable of mating repetitively a relatively large number of times (mean of 6.7 ± 2.7 matings) when given access to new virgin females throughout their lifetimes. Females seldom mated more than once (mean ± 1.3 ± 0.6 matings), indicating a male-biased operational sex ratio. The mean potential lifetime mating was five times higher in males, while the coefficient of variance was lower in males. There was no differences in longevity between animals that were allowed to mate and animals not allowed to mate, indicating no direct costs or benefits of mating in physiological terms. In males, the number of matings was positively correlated with longevity, but this was not the case in females. Nor was there a correlation between the number of female matings and the number of fertilized eggs. There was a negative correlation between the number of eggs fertilized and the number of times males had previously mated, indicating that male ejaculates were limited. Male spermatophore size also decreased with number of achieved matings. Laboratory-reared females attracted males in the field throughout their lifetimes, with a peak at 3–7 days of age. Wild males, allowed to choose between pairs of caged females in the field, were attracted in equal numbers to females of different ages. Females did not show any mate-rejection behavior in the field. They mated with the first male that courted them. No incidence of mate replacement by males arriving later to already courted females were recorded.     

A Comparison of the Efficacy of Nuclear Polyhedrosis and Granulosis Viruses in Spray and Bait Formulations for the Control of Agrotis segetum (Lepidoptera: Noctuidae) in Maize

Agrotis segetum nuclear polyhedrosis virus (AsNPV) and granulosis virus (AsGV), propagated in laboratory cultures of A. segetum in England and A. ipsilon in Spain, respectively, were applied to plots of maize plants at the one‐ to four‐leaf stage of growth. Plots were arranged in a 6 x 6 Latin square design and infested with second‐instar A. segetum larvae (the common cutworm). Each virus was applied in separate treatments by two application methods; as an aqueous spray containing 0.1% Agral as a wetting agent, and as a bran bait. The NPV was applied at a rate of 4 X 10¹² polyhedra/ha, and the GV at 4 X 10¹³ granules/ha. Soil and plants were sampled for larvae on three occasions following virus treatment: 24 h, 4 days and 11 days. The larvae were reared on diet in the laboratory, until death or pupation, to examine the rate and level of viral infection. Infection data showed 87.5% and 91% NPV infection and 12.5% and 55% GV infection in spray and bait treatments, respectively, in larvae sampled 24 h after treatment. In larvae sampled 4 days after treatment, the results were 78% and 100% NPV infection, and 13% and 6% GV infection. A total of only six larvae were retrieved on day 11. In both treatments larvae infected with AsNPV died significantly more rapidly and at an earlier instar than those infected with AsGV, indicating that AsNPV appears to have better potential as a control agent for A. segetum.     

Single cell responses in female Pieris brassicae (Lepidoptera: Pieridae) to plant volatiles and conspecific egg odours

Action potentials from individual olfactory cells and receptor potentials were recorded from antennae of female cabbage white butterflies, Pieris brassicae, using a new ‘surface-contact’ recording technique. Stimuli used were plant volatiles and conspecific egg odours. Most cells were activated by some stimuli and inhibited by others. Hence, the ‘odour spectra’ of most cells included activating as well as inhibiting substances. In addition, the ‘response profile’ of a given stimulus contained both positively and negatively responding cells.Cluster analysis of the odour spectra revealed the existence of moderately separated clusters of olfactory receptors. No groups of cells specifically tuned to odours of eggs or cabbage leaves were found. Analysis of the response profiles did not show a clear clustering of stimuli. The results suggested that the membranes of different receptor cells contain several types of acceptor sites in various proportions.No correlation between EAG and receptor potential amplitude or spike frequency was found. It was concluded that the EAG may be useful in comparing the relative receptor sensitivities only when chemically related compounds are involved.     

松墨天牛成虫对幼虫虫粪挥发性物质的触角电位反应及林间驱避试验

为了研制松墨天牛Monochamus alternatus Hope驱避剂,本文利用触角电位技术和田间试验的方法研究了松墨天牛雌雄成虫对幼虫虫粪挥发性物质的触角电位反应及幼虫虫粪己烷提取物、合成化合物混合物的林间驱避作用。结果表明：α-蒎烯、β-蒎烯、3-蒈烯、柠檬烯和长叶烯均能引起松墨天牛雌雄成虫一定的触角电生理反应,而4-甲基-2,6-二叔丁基苯酚不能引起松墨天牛雌雄成虫的触角电生理反应。林间驱避试验结果说明,幼虫虫粪的己烷提取物处理过的树干上的刻槽数明显少于对照树干上的刻槽数,二者具有极显著差异;有合成化合物的混合物存在的诱捕器诱捕到的雌虫数（平均值3.80±1.02）与对照诱捕到的雌虫数（平均值16.80±1.16）差异极显著。结果显示α-蒎烯、β-蒎烯、3-蒈烯、柠檬烯、长叶烯和4-甲基-2,6-二叔丁基苯酚的混合物对松墨天牛雌虫具有驱避作用,有望开发出一类新的驱避剂。     

Fine-structural characteristics of the antennal sensilla of Agrotis segetum (Insecta: Lepidoptera)

Summary The turnip moth Agrotis segetum possesses seven different types of sensilla: four single-walled (SW), one double-walled (DW), one terminal-pore (TP), and one poreless sensilla (NP).The SW 1 and SW 2 sensilla have the same external appearance, being long and slender, but differ in the branching pattern of the sensory processes: unbranched and branched in SW 1 and SW 2, respectively. The SW 3 sensilla are shorter, sickle-shaped, and contain a large number of branches from the sensory processes. These three sensillar types are innervated by 2–3 sensory cells. The SW 4 sensilla are raisin-shaped and possess three profusely branched sensory processes. The DW sensilla are short and have apical slit-like pores. This sensillar type has 5–6 sensory processes. The TP sensilla possess five sensory processes, one of them terminates basally in a tubular body, the others in the apical part of the long cuticular bristle. The NP sensilla are stout and have apical conelike structures. Two of the sensory processes terminate in the apical part, the third proximally. The third sensory process has a lamellar pattern. The fine structure indicates the following functions: SW and DW sensilla: chemoreception; TP sensillum: chemoreception and mechanoreception; NP sensillum: thermoreception and hygroreception.Supported by joint grants from the Swedish Council for Planning and Coordination of Research, the Swedish Natural Science Research Council, and the Swedish Council for Forestry and Agricultural Research