植物气味化合物与斜纹夜蛾性信息素的协同作用

为提高现有性信息素对雄蛾的引诱活性,本研究通过大量的田间试验探索植物气味化合物与斜纹夜蛾Spodoptera litura性信息素(顺9,反11-十四碳二烯乙酸酯∶顺9,反12-十四碳二烯乙酸酯=10∶1)的协同作用机制。从斜纹夜蛾寄主植物和花的气味化合物中,选择9种有代表性的化合物,并以一定剂量分别加入到斜纹夜蛾性信息素诱芯中,在田间测试对雄蛾的引诱活性。结果表明:在测试的9种植源性化合物中,发现一定剂量(每个诱芯加入0.4mg)的苯乙醛(PAA),具有显著提高斜纹夜蛾性信息素的引诱作用,而高剂量的苯乙醛则强烈抑制性信息素的引诱活性;此外,其他各种浓度的测试化合物或混合物对性信息素则没有统计上显著的增效作用。不同剂量的苯乙醛单个化合物及各种植物气味化合物组成的混合物对斜纹夜蛾也有微弱的引诱作用。苯乙醛必须要与性信息素的完整组分(以10∶1比例混合的顺9,反11-十四碳二烯乙酸酯和顺9反,12-十四碳二烯乙酸酯)混合才能起作用,缺少顺9,反12-十四碳二烯乙酸酯则没有引诱活性。本研究证明,苯乙醛作为理想的性信息素诱芯增效剂,可应用于建立更理想的斜纹夜蛾性信息素诱杀技术,对性诱害虫防治和测报具有应用价值。     

杨小舟蛾MtroOBP1基因的克隆、序列分析及表达

【目的】气味结合蛋白(odorant binding proteins,OBPs)是一种嗅觉相关的蛋白,该蛋白参与大多数气味分子的识别过程,并与气味分子相结合。获得杨小舟蛾[Micromelalopha troglodyta (Graeser)]OBPs以明确其特性。【方法】选择羽化后健康的杨小舟蛾触角为模板,通过反转录聚合酶链反应(RT-PCR)技术克隆杨小舟蛾MtroOBP1基因,利用生物信息学分析软件研究其基因序列和蛋白结构,运用实时荧光定量PCR(qPCR)技术研究MtroOBP1的组织表达模式。【结果】利用RT-PCR技术从杨小舟蛾触角总RNA中扩增得到MtroOBP1基因(GenBank登录号:MN056510),序列分析表明,MtroOBP1开放阅读框为777 bp,一共编码了258个氨基酸残基,且翻译的氨基酸序列仅含有4个保守的半胱氨酸位点,表明得到的OBP基因的编码蛋白不属于典型气味结合蛋白家族,而是属于Minus-C家族。蛋白质理化性质预测显示:MtroOBP1蛋白的分子量为29 664.57 u,等电点为6.23,有18个潜在的磷酸化位点,没有明显的跨膜区,疏水指数为-2.011~3.078,有一个由19个氨基酸组成的信号肽,说明为分泌型蛋白。组织表达模式表明MtroOBP1在杨小舟蛾的各部位都表达,但在触角中表达量最高。【结论】首次克隆得到杨小舟蛾MtroOBP1基因,在触角中高表达,推测其蛋白具有运输气味分子的功能,在杨小舟蛾的嗅觉识别中起着至关重要的作用。     

甜菜夜蛾雄蛾味刷化合物及其功能的初步研究

同大多夜蛾科昆虫一样 ,甜菜夜蛾雄蛾腹部第 8节的末端具有味刷构造 ,当雄蛾被引诱到雌蛾或雌性诱芯附近时 ,呈现典型的振翅、打开味刷、腹末端上弯、追逐雌蛾等预交尾序列行为。为弄清甜菜夜蛾雄蛾打开味刷的生理功能 ,探讨利用雄蛾性信息素防治害虫的新途径 ,我们利用电生理及风洞等行为生测技术进行了研究 ,初步结果如下。(1) GC分析表明 ,甜菜夜蛾雄蛾味刷的正已烷浸提液中含有 3种组分 (I:II:III) ,3者间的比例为 18:2 5 :5 2 %。(2 )求偶观察表明 ,雄蛾味刷浸提液使雌蛾求偶的百分率降低。在整个暗期的雌蛾求偶阶段 ,处理组雌蛾的求偶百分率均小于对照组 ,在暗期后期的差异更大。求偶率下降使平均求偶时间随之明显缩短 ,对照组雌蛾的平均求偶时间为 4 .5 8h,处理组为 3.4 9h,缩短 2 3.80 %。 (3)风洞测定表明 ,雄蛾味刷浸提液对同种雄蛾向雌性性信息素的行为反应没有明显的影响。在雌蛾性信息素中加入 2 0个味刷当量的浸提液 ,对雄蛾向性信息素诱芯的定向飞行、飞行半程以上、接近诱芯及在诱芯上的降落率等指标 ,均无明显影响。 (4)雄蛾味刷浸提液不能引起雄蛾触角明显的 EAG反应 ,表明甜菜夜蛾雄蛾触角上不存在味刷化合物的感受器 ,这与结果(3)也是一致的。上述结果提示 ,在甜菜夜蛾雄蛾接近一只     

棉铃虫对小叶杨萎蔫叶片挥发物成分的触角电位(EAG)反应

用触角电位仪测试了棉铃虫成虫对8种小叶杨萎蔫叶片挥发物及挥发物混配后的触角电位反应。实验结果表明,未交配雄蛾对丁香酚、叶绿醇、3-甲基苯甲醛的触角电位反应值较高;处女蛾对环庚酮、2-羟基苯甲醛、3-甲基苯甲醛的触角电位反应值也较大,交配后的雌雄蛾对苯乙醇的触角电位反应值最高。但成虫都对3-甲基苯甲醛有较强烈的反应(EAG值都较大),将对各自有较大触角电位反应值的3种化合物两两进行混配,成虫对混合物的触角电位反应值总体上有增大的趋势,部分有减小的趋势,但减小的电位值较小。     

蓖麻蚕触角的结构和嗅觉感受细胞对化学气味物质的反应

扫描电镜和透射电镜观察蓖麻蚕的触角和毛形感器。雄蛾触角上的毛形感器比雌蛾的长且多。雄蛾触角的每个毛形感器内有二个或三个树突。用４１种人工合成化合物刺激蓖麻蚕触角，单细胞记录方法记录感受细胞的感受器电位和神经冲动发放发现，雄蛾对Ｅ６，Ｚ１１－十六碳二烯醛和Ｅ４，Ｚ９－十四碳二烯醇，酯及醛反应明显。雌蛾触角对上述化合物无反应。     

蓖麻蚕触角的结构和嗅觉感受细胞对化学气味物质…

扫描电镜和透射电镜观察蓖麻蚕的触角和毛形感器。雄蛾触角上的毛形感器比雌蛾的长且多。雄蛾触角的每个毛形感器内有二个或三个树突。用４１种人工合成化合物刺激蓖麻蚕触角，单细胞记录方法记录感受细胞的感受器电位和神经冲动发放发现，雄蛾对Ｅ６，Ｚ１１－十六碳二烯醛和Ｅ４，Ｚ９－十四碳二烯醇，酯及醛反应明显。雌蛾触角对上述化合物无反应。     

色板对不同作物害虫的引诱作用

色板是害虫防治的一种重要工具,本文测定了10种不同色板对4种作物8种害虫的引诱作用。结果表明：黄色对桃蚜、桃小绿叶蝉、枇杷蚜虫、枇杷菱纹叶蝉和茶黑刺粉虱的引诱力均较其它色板的强;黄色和白色对黄曲条跳甲的引诱作用最强,而绿色对黄曲条跳甲也表现出一定的引诱作用;绿色对小菜蛾的引诱作用较强;10种色板对茶小绿叶蝉的引诱作用相当,差异不显著。     

安徽农业大学在植物抗虫研究领域取得新进展

小菜蛾系鳞翅目重要害虫,主要摄食甘蓝、青菜、花椰菜、大白菜、油菜等十字花科作物.小菜蛾生长周期短,繁殖速度快,世代重叠迅速,成虫羽化为蛾后具有强迁徙性,而且由于化学农药的大量使用,族群中已产生较强的抗药性,易给蔬菜农业生产造成严重危害.因此,开发新型有效的生物农药,并探究植物如何抵御小菜蛾的侵食,对开展农作物抗虫育种具有重要意义.     

昆虫的嗅觉与仿生

嗅觉对昆虫非常重要,多数昆虫通过嗅觉寻找食物、配偶、产卵场所以及逃避天敌。触角是昆虫主要的嗅觉感受器官,不同种类昆虫的触角呈现不同形状,如棉铃虫的触角为线状,蝴蝶的为锤状,家蝇的为具芒状,柞蚕雄蛾的触角为羽状。昆虫触角就像电视机上的天线,可左右上下不停地摆动,以感知来自不同方位的气味。感受化合物的是触角上的各种各样的感器,感器按形状大致可分为毛形、锥形、刺形、腔形、坛形、板形、耳形等。不同形状的感器具有不同的功能,其中毛形和锥形感器,是感受环境中的气味化合物的主要嗅觉感器。不同种昆虫的感器在类型和数量上也…     

桔小实蝇对寄主水果气味的趋向反应测试

 西双版纳勐仑植物园、思茅港、河口3个地点的桔小实蝇对3种不同成熟阶段芒果以及3种水果(芒果、苹果、梨)挥发物气味的趋性反应说明,雌成虫较雄成虫易受成熟度高,软、挥发物气味浓的水果气味的吸引.通过方差分析和多重比较表明:在不同成熟阶段芒果的引诱实验中,雌虫对黄软芒果气味的趋性最强.河口地区雌虫被芒果气味的引诱到的数量高于其它地区;在对3种不同寄主的趋性反应中,雌虫和雄虫对芒果的趋性强于苹果和梨.3种的水果的几种处理中黄软芒果各种处理对雌虫的引诱效果均较好,其中果肉泥气味的吸引最强.河口地区雌虫的被引诱到的数量仍高于其它地区.     

光肩星天牛对糖槭挥发物的EAG及嗅觉行为反应

[目的]分析影响光肩星天牛定位寄主的糖槭挥发物成分,解析挥发物在光肩星天牛搜寻和定位寄主过程中的作用,为光肩星天牛的综合防控提供依据.[方法]利用热脱附气质联用法(thermal desorption gas chromatog-raphy-mass spectrometry,TCT-GC-MS)分析鉴定糖槭挥发物组分...     

小菜蛾生态控制措施对十字科蔬菜节肢动物群落的影响

本文调查了十字花科蔬菜田节肢动物群落组成 ,分析蔬菜品种之间各群落物种丰富度、多样性指数以及发生数量的变化 ,阐明对小菜蛾实施生态措施 ,可有效地保护菜田自然天敌 ,为小菜蛾种群的持续控制提供依据     

银杏外种皮中银杏酚酸对小菜蛾幼虫的拒食及毒杀作用

小菜蛾(Plutella zylostella L.)是一种全球性的重要害虫,其抗药性引起国际学术界的广泛关注,而开发高效、低毒、低残留、无污染的生物农药成为了国内外农药开发的主流．报道了从废弃的银杏(Ginkgo biloba L.)外种皮中分离到的银杏酚酸对小菜蛾的拒食和毒杀作用．实验采用皂化和酯化反应及柱层析方法从银杏外种皮中分离获得银杏酚酸,并对1～3龄小菜蛾幼虫进行生物测定．生测结果表明银杏酚酸对小菜蛾有较好的拒食和毒杀作用．当处理的质量浓度为6．25mg／L时3龄幼虫的非选择性拒食率在24,48h后分别达到77．8％,94．7％以上．处理时间达到48h时,1～2龄幼虫的LC50为1.31mg／L,3龄幼虫的LC50为6．07mg／L．这表明了银杏外种皮有很好的开发前景,将为今后新型植物农药的开发和银杏废弃物的综合利用提供依据．     

苦瓜叶片正丁醇萃取液对小菜蛾取食及生理特性的影响

用苦瓜叶正丁醇萃取液的3个质量浓度梯度（0．001、0．002、0．004mg／L）处理小菜蛾幼虫．结果表明,正丁醇萃取液对小菜蛾幼虫的取食及生理特性有显著影响．随着萃取液质量浓度的升高,小菜蛾幼虫的取食量逐渐减少,表现出很强的拒食作用,特别是萃取液质量浓度为0．004mg／L时,24h的拒食率达到90％以上．同时小菜蛾幼虫的POD和CAT活力水平显著提高,表明试虫体内的保护酶体系在萃取液的影响下严重失衡．     

日本双棘长蠹成虫对8种植物挥发物的EAG和行为反应

为了寻找新型的防治日本双棘长蠹(Sinoxylon japonicum Lesne)的植物源引诱剂,分别测定了成虫对8种植物挥发物的EAG和行为反应.EAG测定结果表明:1.00 mol/L的愈创木酚和邻苯二甲酸二甲酯均能引起日本双棘长蠹较强的EAG反应(p≤0.05)."Y"型嗅觉仪测定结果表明:1.00 mol/L的愈创木酚对日本双棘长蠹成虫的引诱效果最好,选择率达到57%;1.00 mol/L的邻苯二甲酸二甲酯对日本双棘长蠹成虫具有较好的驱避作用.其他挥发物对日本双棘长蠹均无明显的定向作用.     

Cloning,expression and binding specificity analysis of odorant binding protein 3 of the lucerne plant bug, <Emphasis Type="Italic">Adelphocoris lineolatus</Emphasis> (Goeze)

Credible evidence shows that odorant binding proteins (OBPs) are required for insect olfaction perception and play a key role in transporting hydrophobic odorants across the sensillum lymph to the olfactory receptors (ORs). In the present study, a novel OBP (AlinOBP3) gene from the lucerne plant bug, Adelphocoris lineolatus, was cloned and expressed. The expression pattern of AlinOBP3 was evaluated by qPCR, which indicated that AlinOBP3 was dominantly expressed in antennae. The binding properties of AlinOBP3 with 9 cotton volatiles and 5 sex pheromone analogs were measured by fluorescence competitive binding assays with the fluorescence probe 1-NPN. The results revealed that of 9 cotton volatiles, Myrcene, β-Ocimene and α-Phellandrene can bind with AlinOBP3. α-Phellandrene especially bound to AlinOBP3 with a high binding affinity, with a dissociation constant of 56.68 μmol/L. Of the 5 sex pheromone analogs, Hexyl butyrate had the strongest binding affinity with AlinOBP3, with a dissociation constant as 59.53 μmol/L. Butyl butyrate, trans-2-Hexenyl butyrate and Ethyl butyrate had medium binding affinities with AlinOBP3, with dissociation constants of 227.39, 108.77 and 143.47 μmol/L, respectively. The results suggest that AlinOBP3 might be a pheromone binding protein (PBP) with a dual-function for the perception of sex pheromones and plant volatiles.     

A practical artificial diet for the diamondback moth

A new artificial diet for the diamondback moth,Plutella Xylostella (L), had been selected out successfully. The diet contained the following constituents: soybean powder, wheat germ, wheat bran powder, brewer's yeast and other constituents. So far, the diamondback moth had been reared on this artificial diet for 25 generations and still mantained its normal biological characteristics. Under 25±1 C and 60%–75%RH with 12 h PH, the results of rearing the diamondback moth on the diet as follows: egg hatch, 81.3%–94.7%; survival from eggs to pupae, 55.0%–76.7%; pupal survival, 79.7%–100%; adult emergence, 80%–100%; fecundity 94.7–144. 4 eggs/♀; pupal weight, 90.4–110.8 mg/20 pupae; average days to adult: ♀, 10.2; ♂ 13.1. The diet is not only simpler on the constituents but also have better rearing results and more rearing generations. Li Guanghong: born in June 1965, Ph.D. graduate student. Current research interest is in entomo logical physiology Supported by the State Eighth Five-Year-Plan     

Behavioral and olfactory responses of grasshopper hatchlings,<Emphasis Type="Italic">Melanoplus sanguinipes</Emphasis>, to plant odours and volatile compounds

Behavior and olfactory responses of grasshopper hatchlings, Melanoplus sanguinipes (F.), to odours from plant foliage and volatile compounds were tested using a glass Y-tube olfactometer and electroantennogram (EAG)techniques respectively. In single choice trials, newly hatched hoppers were much more sensitive to the odour from intact leaves and chopped foliage of ryegrass and wheat than other plants. Chopped sorghum leaves, but not stem-cut sorghum,were also significantly attractive. The orientation responses of grasshopper hatchlings to these plants were highly consistent with those of last instar hoppers and adults. When ryegrass was employed as the control, the odour from stem-cut alfalfa was more attractive. There was no significant difference in hopper orientation responses to the odours from chopped seedlings of sorghum, alfalfa, wheat or ryegrass.However, significantly more hoppers preferred the chopped ryegrass control to chopped Louisanna sage. Measurement of the EAG response of first instar hoppers to these plant odours showed that the odour of Louisanna sage elicited the greatest response amplitudes. In olfactory tests using different volatile components, Z-3-hexenol, E-3-hexenol,Z-hex-3-enyl acetate, E-2-hexenal and hexenal gave greater EAG responses than geraniol and 1-octen-3-ol. These results are also consistent with comparable data from adults. Newly hatched grasshoppers had similar EAG response profiles to plant materials and chemicals to those of adults, although the absolute EAG values of young hoppers were much lower than those of adults. Therefore, newly hatched hoppers were able to distinguish plants from an air control, and even host plants from non-host plants, and the feeding experience of hoppers probably has little influence on their subsequent ability as adults to identify and locate food plants.     

小菜蛾对杀虫双和杀螟丹抗性与艾氏剂环氧化活性

利用室内选育１１９代的抗杀虫双、抗杀螟丹小菜蛾品系和敏感品系,研究了各杂交世代小菜蛾对杀虫双和杀螟丹的敏感性．通过反复回交建立小菜蛾对杀虫双和杀螟丹抗性的近等基因系．测定了各杂交世代和近等基因系的多功能氧化酶环氧化活性．结果表明,抗性品系和抗性近等基因系多功能氧化酶环氧化活性比敏感品系高,杀虫双、杀螟丹抗性品系和杀虫双、杀螟丹抗性近等基因系分别是敏感品系的１．６２、１．８３、１．５６和１．９７倍,因此,多功能氧化酶环氧化活性提高与小菜蛾对杀虫双和杀螟丹抗性有关     

Pheromone binding and inactivation by moth antennae

The antennae of male silk moths are extremely sensitive to the female sex pheromone such that a male moth can find a female up to 4.5 km away. This remarkable sensitivity is due to both the morphological and biochemical design of these antennae. Along the branches of the plumose antennae are the sensilla trichodea, each consisting of a hollow cuticular hair containing two unbranched dendrites bathed in a fluid, the receptor lymph ,3. The dendrites and receptor lymph are isolated from the haemolymph by a barrier of epidermal cells which secreted the cuticular hair. Pheromone molecules are thought to diffuse down 100 A-wide pore tubules through the cuticular wall and across the receptor lymph space to receptors located in the dendritic membrane. To prevent the accumulation of residual stimulant and hence sensory adaptation, the pheromone molecules are subsequently inactivated in an apparent two-step process of rapid 'early inactivation' followed by much slower enzymatic degradation. The biochemistry involved in this sequence of events is largely unknown. We report here the identification of three proteins which interact with the pheromone of the wild silk moth Antheraea polyphemus: a pheromone-binding protein and a pheromone-degrading esterase, both uniquely located in the pheromone-sensitive sensilla; and a second esterase common to all cuticular tissues except the sensilla.