【作者】 杨慧；

【导师】 严善春；

【作者基本信息】 东北林业大学 ， 森林保护学， 2008， 硕士

【摘要】 兴安落叶松鞘蛾[Coleophora obducta（Meyrick）]在落叶松叶部潜叶危害,在我国东北林区的落叶松林内常爆发成灾,危害严重时,林分似火烧状,甚至会导致大量林木枯死,造成很大的经济损失,目前尚没有有效的方法从根本上控制其猖獗危害。植物挥发物大多具有一定的“气味”,作为影响昆虫行为的化学信号物质,在植物之间以及植物与昆虫之间起着重要作用,而无公害防治作为一种绿色的、环境友好的防治手段,在实际应用中也越来越受到重视。本文首次研究了兴安落叶松鞘蛾对落叶松挥发物和无公害药剂的反应,首次观察了鞘蛾触角感器的超微结构,为探索昆虫与植物化学信息联系以及开展林间无公害防治提供理论依据。应用触角电位仪测试了鞘蛾对落叶松9种挥发物,即R-α-蒎烯、S-α-蒎烯、β-蒎烯、罗勒烯、水芹烯、3-蒈烯、月桂烯、莰烯和叶醇的触角电位（EAG）反应。结果表明,在0.4mol L^-1浓度下,雌蛾除了对R-α-蒎烯、雄蛾除了对R-α-蒎烯和水芹烯没有明显EAG反应外,对其余挥发物的EAG反应与对照相比差异均达到显著水平（P＜0.05）,并且,鞘蛾对不同挥发物的EAG反应在雌、雄间也存在一定差异。应用“Y”型嗅觉仪测定鞘蛾对上述9种挥发物在0.0004、0.004、0.04、0.4、0.8mol L^-1这5个浓度梯度下的行为反应。雌蛾对S-α-蒎烯0.004mol L^-1,S-β-蒎烯0.0004mol L^-1,水芹烯、叶醇0.04mol L^-1,3-蒈烯0.0004、0.04mol L^-1有诱引反应（P＜0.05）;对S-α-蒎烯0.04mol L^-1,水芹烯0.0004mol L^-1,月桂烯0.004、0.8mol L^-1有驱避反应（P＜0.05）。雄蛾对罗勒烯、月桂烯0.0004mol L^-1,叶醇0.004mol L^-1有诱引反应（P＜0.05）;对莰烯0.004、0.0004mol L^-1有驱避反应（P＜0.05）。根据上述嗅觉反应结果筛选对雌虫有活性的挥发物成分和浓度,喷施到健康落叶松笛上,观察成虫的嗅觉和产卵行为以及幼虫的取食行为。结果表明,S-α-蒎烯0.004molL^-1、S-β-蒎烯0.0004mol L^-1和3-蒈烯0.04mol L^-1对雌成虫有诱引作用（P＜0.05）,S-α-蒎烯0.04mol L^-1和月桂烯0.8mol L^-1对雌成虫有驱避作用（P＜0.01）;喷施挥发物的样枝上,月桂烯0.004mol L^-1造成幼虫的死亡虫数最少,与对照差异不显著（P＞0.05）,其他样枝上幼虫死亡率较对照差异极显著（P＜0.01）,其中,S-α-蒎烯0.04mol L^-1造成幼虫的死亡率最高,达86.67%;喷施挥发物均能够显著降低鞘蛾在落叶松苗上的产卵量,与对照的平均每雌产卵量15.79枚相比差异显著（P＜0.05）,其中,鞘蛾在喷施水芹烯0.0004mol L^-1和月桂烯0.8mol L^-1的落叶松苗上的平均每雌产卵量最少,分别为5.63枚和5.21枚,但二者间差异不显著（P＞0.05）。为探索无公害药剂对鞘蛾行为的影响和防治效果,利用7种无公害药剂测试了鞘蛾雌虫的行为趋向和产卵反应。结果表明,仅有吡虫啉3000倍液和甲胺基阿维菌素苯甲酸盐微乳剂2000倍液表现出对鞘蛾的驱避作用。鞘蛾在喷施无公害药剂的落叶松枝条上的产卵量与对照及喷施挥发物相比显著减少（P＜0.05）,其中,在喷施阿维菌素和吡虫啉枝条上的产卵量最少,平均每雌产卵量分别为3.13枚和3.33枚,但二者间差异不显著（P＞0.05）。应用扫描电镜对鞘蛾触角及其感器进行了观察和研究。兴安落叶松鞘蛾触角为丝状,其上共有8种感器:板形感器、锥形感器、腔锥形感器、栓锥形感器、毛形感器、鳞形感器、叉形感器和B（o|¨）hm氏鬃毛。对各种感器的形态、分布特点进行了描述,推测其可能具有的功能。板形感器在雌、雄蛾触角上数量最多,毛形感器次之;鳞形感器为雌、雄蛾末节鞭亚节特有;首次发现叉形感器,数量少,仅在雌蛾触角上零星分布,该感器功能尚不清楚。雌、雄蛾触角有明显的性二型现象,表现为雌、雄触角大小不同,触角感器类型、大小、数量、分布不同。透射电镜观察到板形感器、锥形感器和毛形感器受神经元支配,推测具有化学感受功能;栓锥形感器的神经元终止于类似管状体的结构,推测具有味觉/机械感受功能。此外,发现触角顶端分布有感觉栓,推测具有机械感受功能。综上所述,寄主植物落叶松挥发物能够对兴安落叶松鞘蛾嗅觉、取食、产卵等行为产生不同程度的影响,无公害药剂也能一定程度地影响鞘蛾行为趋向和产卵反应,因此,可将外源植物挥发物和无公害农药用于落叶松鞘蛾的综合治理,达到生态安全地控制鞘蛾危害的目的;昆虫感器研究也为进一步探讨昆虫与植物信息联系奠定理论基础。更多还原

【Abstract】 Coleophora obducta（Meyrick）（Lepidoptera:Coleophoridae）,a kind of larch defoliators exclusively latent in leaves,frequently break out in larch forest of northeast China,which appeared burned and resulted in dried up when severely harmed,causing prodigious economic losses,and had no effective methods to control the rampant damage yet.Plant volatiles served as a sort of behavior-implict chemical signals played important roles between plants and insects,moreover,environmental safe insecticides accepted as green and friendly control method had been increasely paid much attention to on practical use.This article studied the responses of C.obducta to host plant volatiles and environmental safe insecticides,observed the ulstructuer of antennal sensilla for the first time,which provided theoretical basises for exploring chemical communications between plants and insects,and developing environmental safe control in field.This article tested the EAG responses of C.obducta to nine kinds of larch volatiles, namely R-α-pinene,S-α-pinene,β-pinene,ocimene,phellandrene,3-carene,myrcene, camphene and phytol.The results showed that,in concentration of 0.4mol L^-1,most volatiles had significant EAG responses compared with the blank（P＜<0.05）,except females to R-α-pinene, males to R-α-pinene and phellandrene;Besides,EAG responses between males and females also existed differences.Observations of behavioral responses of C.obducta to the above nine kinds of volatiles in a series of concentrations of 0.0004,0.004,0.04,0.4,0.8mol L.（-1） had been carried out with the application of Y-tube olfactometer.Females were attracted by S-α-pinene 0.004mol L^-1,S-β-pinene 0.0004mol L^-1,phellandrene,phytol 0.04mol L^-1,3-carene 0.0004 and 0.04mol L^-1 （P＜0.05）,whereas repelled by S-α-pinene 0.04mol L^-1,phellandrene 0.0004mol L^-1,myrcene 0.004 and 0.8mol L^-1;Males were lured by ocimene,myrcene 0.0004mol L^-1 and phytol 0.004mol L^-1,whereas repulsed by camphene 0.004 and 0.0004mol L^-1（P＜0.05）.We adopted volatiles that activated to females,then sprayed them singly to healthy larch seedlings,the results indicated that S-α-pinene 0.004mol L.（-1）,S-β-pinene 0.0004mol L.（-1）,and 3-carene 0.04mol L^-1 attracted the females（P＜0.05）;Whereas,S-α-pinene 0.04mol L.（-1） and myrcene 0.8mol L^-1 repelled the females（P＜0.01）;Most larvae that feeding on twigs spyayed with volatiles were dead compared to the blank（P＜0.01） with exception of myrcene 0.004mol L^-1 which had no significance（P＞0.05）,the phenomenon suggested that volatiles may be harmful to larvae,thereinto,S-α-pinene 0.04mol L.（-1） caused the most larvae dead,which accounted for 86.677%of total number.Otherwise,sprayed with volatiles could reduce eggs that laid on larch seedlings compared with the blank of mean eggs of 15.79 per female,and among which sprayed with phellandrene 0.0004mol L^-1 and myrcene 0.8mol L^-1 had the least oviposition with mean eggs per female 5.63 and 5.21 respectively,and the two had no significant differences（P＞0.05）.In order to expolre the influencese of environmental safe insecticides to C.obducta and effect of control,we tested the tendency and oviposition responses of female C.obducta to seven kinds of environmental safe insecticides,found that,imidacloprid EC 3000 times solution and emamectin benzoate microemulsion 2000 times solution rejected the C.obducta, with repellent rate 75.00%and 68.75%respectively.Eggs that laid on larch seedlings sprayed with environmental safe insecticides were notably depressed in contrast to both the blank and seedlings that sprayed with volatiles（P＜0.05）,and among which sprayed with avermectin and imidaclopridhad the least oviposition with mean eggs per female 3.13 and 3.33 respectively, and the two had no significant differences（P＞0.05）.Antennae and their sensilla of C.obducta were observed using scanning electron microscopy.Both sexes of antennae were threadlike,and totally,there were eight types of sensilla found:sensilla placodea,sensilla basiconica,sensilla coeloconica,sensilla styloconica, sensilla trichodea,sensilla squamiformia,sensilla furcatea and B6hm bristles,respectively.The shapes,distributions and putative functions of sensilla were described and discussed.Thereinto, sensilla placodea accounted for the most of both moths’ antennal sensilla,and sensilla trichodea took second place;Sensilla squamiformia exclusively scattered on the last segment of male and female flagella.Sensilla furcatea were found for the first time,sporadic distributed on female antenna,and the function of this type was not clear yet.Moreover,there were obviously sex dimorphisms,including different antenna sizes,different sensilla shapes,sizes, numbers and distributions.Using transmission electron microscopy（TEM） to illustrate the ultrastructures and possible functions of antennal sensilla of C.obducta.Sensilla placodea,basiconica and trichodea were found to be innervated by sensory neurons,we inferred from their ultrastmctures as chemoreceptors;Besides,the neuron of sensilla styloconica terminated in a tubular body-like structure typified gustatory/mecheanosensory function,and the terminal sensory pegs may function as contact-chemoreceptors because of their location.In a word,larch volatiles and environmental safe insecticides could influence the behaviors of C.obducta such as olfaction,feeding and oviposition to some extent,which providing a new thought to pest control,otherwise,studies on antennal sensilla would also establish a theoretical foundation on further research of insect-plant communication.更多还原