松梢象对红松萜烯类挥发物的触角电位及行为反应

本文研究了松梢象对寄主红松挥发物组分S型α一蒎烯、R型α一蒎烯、卢一蒎烯、β一月桂烯、罗勒烯、莰烯、3一蒈烯及反一柠檬烯8种挥发物,在0．0004、0．004、0．04、0．4及0．8mol／L浓度下的触角电位反应及行为反应。结果表明：这8种挥发物单体在各浓度下均能引起松梢象的触角电位（EAG）反应,且相同挥发物EAG...     

Floral attractants for the female soybean looper, Thysanoplusia orichalcea (Lepidoptera: Noctuidae)

BACKGROUND: The soybean looper, Thysanoplusia orichalcea (F.), is a polyphagous insect pest of vegetable crops. Indonesian in origin, it has spread to Europe, India, Africa, Australia and New Zealand. The identification of an attractant for female T. orichalcea could enable the development of alternative pest management strategies to those provided by insecticides or sex pheromones, which are often only attractive to males. RESULTS: Traps baited with synthetic lures derived from Canada thistle, Cirsium arvense (L.) Scop., floral volatiles attracted female T. orichalcea. Phenylacetaldehyde, a floral compound attractive to many Lepidoptera and present in C. arvense, was tested alone as an attractant for the soybean looper and caught significantly more female than male T. orichalcea. Trap catch was greatest when phenylacetaldehyde was combined with five prevalent volatiles present in C. arvense headspace collections: 2‐phenylethyl alcohol, methyl salicylate, dimethyl salicylate, benzaldehyde and benzyl alcohol. Twice as many female moths as males were collected. CONCLUSION: Successful trapping of female T. orichalcea in either a lure‐and‐kill or a mass trapping system may offer an effective way to manage its population size. Copyright © 2008 Society of Chemical Industry     

Diurnal variation of walnut tree volatiles and electrophysiological responses in Cydia pomonella (Lepidoptera: Tortricidae)

BACKGROUND: In recent years, many studies have been carried out on the behavioural and electrophysiological responses of Cydia pomonella (L.) to host volatile emissions, to find alternative attractants to the sex pheromone for pest monitoring. These studies have focused on apple and pear, and very little has been done on walnut. In the present work, the diurnal and seasonal variation in walnut volatile emissions and the electrophysiological response of C. pomonella have been studied. RESULTS: Ninety compounds were detected in walnut emissions, mainly monoterpenes and sesquiterpenes. The most abundant compound was β‐pinene, which, together with (Z)‐3‐hexenyl acetate, (E)‐β‐ocimene, limonene, germacrene D, 1,8‐cineole, sabinene, (E)‐β‐farnesene, (E)‐β‐caryophyllene, β‐myrcene and β‐phellandrene, constituted between 81.9 and 90.5% of the total chromatographic area. Differences between seasonal periods were significant for 39 compounds, and between daytimes for 14 compounds. Discernible and consistent EAD responses were detected to 11 walnut‐origin compounds, and confirmed with synthetics to seven of them. Except for alloocimene, pinocarvone and caryophyllene oxide, all these compounds are also emitted by apple. CONCLUSION: Walnut volatile emissions differ widely from apple ones, but both share many compounds that are EAD‐active in C. pomonella. However, among EAD‐active compounds there are three walnut‐specific ones, which should be further tested in behavioural assays. Copyright © 2008 Society of Chemical Industry     

非寄主植物提取物对橘小实蝇的产卵拒避作用

选取4种非寄主植物柠檬桉Eucalyptus citriodora、樟树Cinnamomum camphora、白千层Melaleuca leucadendron、夹竹桃Nerium indicum,初步研究了这4种植物叶子提取物对橘小实蝇Bactroceradorsalis的产卵拒避作用。以无水乙醇作溶剂,供试4种植物中的白千层提取物对橘小实蝇具有较强的产卵拒避作用。检测了橘小实蝇对4种植物的乙醇提取物的触角电位值,发现各生物测定值与雌虫触角电位值呈显著相关性,表明其中的挥发性组分是橘小实蝇对植物提取物产生拒避反应的重要原因之一。用无水乙醇、乙醚、石油醚、二氯甲烷作溶剂,分别提取白千层叶,仅乙醇提取物有显著拒避作用;用这4种溶剂分别提取樟树叶,则无水乙醇、乙醚、石油醚作溶剂的提取物都有较好效果。     

Repellent effects of five monoterpenoid odours against Tribolium castaneum (Herbst) and Rhyzopertha dominica (F.) in Calabar, Nigeria

Secondary plant compounds are recognised as important components of plant defence system against herbivores and pathogens. Five monoterpenoids, (R)-linalool, 1,8-cineole, (S)-2-heptyl acetate, (S)-2-heptanol and citral, which are natural components of the essential oils of Aframomum melegueta (K. Schum) and Zingiber officinale (Roscoe), were tested at the ratios in which they occur naturally for repellent activity against Tribolium castaneum (Herbst.) and Rhyzopertha dominica (F.) in a 4-way olfactometer. The results showed the repellent properties of the compounds as both beetles spent less time in the olfactometer arm containing the test stimuli. (R)-linalool and (S)-2-heptanol were stronger repellent compounds than the others. Linalool showed good repellent activity against T. castaneum (P = 0.001) as the insect spent 1.22 min in the test arm compared to the control arms (2.78 min), and R. dominica (P = 0.001) with 0.89 min in the test arm compared to 2.87 min in the control arms. With (S)-2-heptanol, T. castaneum spent 1.23 min in the test arm compared to 2.83 min in the control arms. R. dominica spent 1.61 min in the test arm and 2.69 min in the control arms. For the number of entries or visits made, while both insects were significantly repelled (P < 0.05) by the linalool-treated arm than the control, only R. dominica was repelled by the (S)-2-heptanol-treated arm (P = 0.038) compared to the control arms. The results indicate that A. melegueta and Z. officinale essential oils and their components could be suitable as safer repellents or fumigants against T. castaneum and R. dominica.     

Effects of Microtubule Polymerization Inhibitor on the Hypersensitive Response of Wheat Induced by the Non-Host Pathogen Sphaerotheca fuliginea

The plant cytoskeleton is a highly dynamic and versatile intracellular scaffold composed of microtubules and microfilaments, serving a multiplicity of functions in plant cells. To reveal the relationship between the cytoskeleton in wheat （Triticum aestivum L.） cv. Suwon 11 attacked by the non-host pathogen Sphaerotheca fuliginea and the initiation of the hypersensitive response, the microtubule inhibitor oryzalin was injected into the wheat leaves immediately prior to inoculation. The incidence of hypersensitive cell death was significantly lower than that in water-treated control. In addition, the occurrence of hypersensitive cell death was also delayed and S. fuliginea was able to penetrate and form haustoria in epidermal tissues of wheat. All the results above indicated that hypersensitive cell death was associated with depolymerisation of microtubules, suggesting that microtubules might play an important role in the expression of non-host resistance of wheat.     

水稻对褐飞虱的抗性与挥发性次生物质总量的关系

运用水蒸气蒸馏法提取水稻植株的挥发性次生物质,并进行GC/MS分析,比较水稻抗、感褐飞虱植株中挥发性次生物质总量的差异.结果表明,感性植株的挥发性次生物质总量明显高于抗性植株,前者比后者高45.4%;挥发性次生物质总量随植株抗性增强而降低,1级最低,7级最高;挥发性次生物质总量随植株所含抗性基因数的增加而减少.     

亚洲小车蝗成虫体表挥发物化学成分分析

采用专用吸附剂对亚洲小车蝗(Oedaleus asiaticus B.Bienko)成虫体表挥发物进行收集,并通过气相色谱和质谱联用(GC-MS)技术进行了分析。结果表明:亚洲小车蝗雌、雄成虫体表挥发物的组分基本相同,主要含有醛类和醇类,只是各化合物在挥发物中所占的比例不同。其中壬醛和癸醛在挥发物中所占比例较高,雌虫体中分别占56.05%和24.34%,雄虫体中分别占56.48%和22.97%。     

苹毛丽金龟性信息素嗅觉行为与释放模式

苹毛丽金龟在我国很多地区是重要经济害虫。在实验室利用采集的两性及寄主挥发物测试雌雄行为反应,结果表明,苹毛丽金龟通讯行为受寄主植物和性信息素调控。添加了雌性挥发物的寄主植物挥发物,能增加对雄虫的吸引力。喂食与不喂食李子花对性信息素释放具有显著影响。气相色谱及行为学研究证实至少有一种物质作为性信息素存在于雌性挥发物中。光期开始后4~6小时,是雌性信息素释放的高峰期。     

双花鞘花寄生挥发油化学成分的GC-MS分析

采用水蒸气蒸馏法提取了双花鞘花(Macrosolen bibracteolatus)寄生的挥发油组分,利用气相色谱-质谱联用技术(GC-MS)对挥发油的化学组成进行了分离分析,通过与计算机标准谱库对照鉴定了部分化学成分的结构,采用峰面积归一化法测定了各个化学成分的相对含量。结果表明,从双花鞘花寄生挥发油中共分离出65个色谱峰,鉴定了其中41个化学成分的结构,已鉴定成分的相对含量占挥发油总量的81.94%。化合物类型以萜类为主,含量较高的挥发油成分是α-芹子烯(23.30%)和(4αR-trans)-十氢-4α-甲基-1-亚甲基-7-(1-甲基亚乙基)-萘(21.07%)。