【作者】 任利利；

【导师】 骆有庆； 石娟；

【作者基本信息】 北京林业大学 ， 森林保护， 2014， 博士

【摘要】 松材线虫病又称松树萎蔫病,在我国是松树的毁灭性病害,其病原松材线虫(Bursaphelenchus xylophilus)借助松墨天牛(Monochamus alternatus)等媒介昆虫通过补充营养和取食在松树间传播。松墨天牛成虫羽化后取食松嫩枝补充营养,雌虫性成熟后多选择衰弱木或新伐木产卵。花绒寄甲(Dastarcus helophoroides)属鞘翅目寄甲科(Coleoptera:Bothrideridae),莱氏猛叩甲(Tetrigus lewisi)属鞘翅目叩甲科(Coleoptera:Elateridae),分别是松墨天牛重要的寄生性天敌和捕食性天敌。本文主要从以下方面开展了研究：松墨天牛的寄主树种马尾松(Pinus massoniana)和黑松(P. thunbergii)不同发病阶段的挥发物变化,松林群落中主要6种阔叶乔木(香樟Cinnamomum camphora、枫香Liquidambar formosanat、构树Broussonetia papyrifera、黄檀Dalbergia hupeana、合欢Albizia julibrissin和檫木Sassafras tzumu)的挥发性物质组分；并测定了松墨天牛和天敌花绒寄甲对上述植物挥发物的电生理和行为学反应,主要结果如下：1、明确了松材线虫侵染后各发病阶段马尾松与黑松上松墨天牛及天敌的株虫口密度和生态位：处于健康期的松树上无松墨天牛；发病初期的马尾松和黑松上分布有松墨天牛当年刻槽,但这一时期内其幼虫的生态位较窄；发病早期至后期松树上松墨天牛的当年刻槽多,幼虫生态位宽度显著高于其它时期,且株虫口密度高。同时,松墨天牛捕食性天敌莱氏猛叩甲的分布、株虫口密度与松墨天牛的生态位、株虫口密度显著相关,说明其对松墨天牛有跟随作用；在所调查的30棵发病松树上,均未发现花绒寄甲。2、揭示了各发病阶段马尾松和黑松挥发物质成分与挥发量的变化规律：随着发病程度加深,松树挥发性物质的总量逐渐减少,在发病后期和末期最少。发病初期或早期的马尾松树干、枝叶及黑枝叶、树干挥发物中limonene和3-carene的挥发量呈上升趋势,黑松树干挥发的α-pinene有同样趋势。发病中期,黑松和马尾松树干的主要挥发物质成分为α-pinene, β-pinene, limonene和3-carene,同时期枝叶主要挥发性物质除上述4种外还包括β-phellandrene。从健康期到发病中期,黑松和马尾松树干挥发物中α-pinene所占比例上升,β-pinene的比例下降,limonene,3-carene的比例先上升后下降；黑松和马尾松枝叶挥发物中3-carene和β-pinene的比例均上升,a-pinene的比例下降。3、测定了松墨天牛对发病初期至后期的黑松和松林群落中6种阔叶乔木挥发性物质的触角电位和行为反应：天牛雌雄成虫在EAG试验中反应敏感且在行为试验中具有趋向反应的物质包括3-carene,(R)-(+)-a-pinene,(S)-(-)-a-pinene, camphene,(R)-(+)-limonene,(S)-(-)-limonene, β-phellandrene,β-myrcene(发病黑松与阔叶树均挥发),linalool, cis-3-hexene-l-ol和methyl salicylate(仅阔叶树挥发)；行为测定中仅雌虫趋向的化学物质为α-terpinene,(-)-α-cedrene(仅发病黑松挥发)和(-)-β-caryophyllene(发病黑松与阔叶树均挥发)；雌雄虫均趋避的物质包括camphor, octanal,ocimene以及α-farnesene(仅阔叶树挥发)；衰弱寄主植物的挥发物对松墨天牛具有吸引作用,而非寄主植物的挥发物会干扰松墨天牛的寄主找寻。4、测定了花绒寄甲对发病黑松和阔叶乔木挥发性物质的触角电位与行为反应：雌雄花绒寄甲的EAG反应随着待测物质浓度的加大而增大；引起花绒寄甲产生较强反应的物质为nonanal和octanal(仅阔叶树挥发),其次为cis-3-hexen-l-ol(仅阔叶树挥发),3-carene,(R)-(+)-α-pinene,(S)-(-)-α-pinene,(R)-(+)-limonene以及(S)-(-)-limonene(发病黑松与阔叶树均挥发)。行为测定中,花绒寄甲被(R)-(+)-α-pinene和(S)-(-)-α-pinene在高浓度下吸引；被3-carene,cis-3-hexen-l-ol,nonanal和octanal低浓度下所吸引；可被(R)-(+)-limonene在所有浓度下吸引。5、明确了松墨天牛求偶识别和产卵探测行为中主要功能感器的形态和超微结构：松墨天牛雄虫的触角,下颚须和下唇须均参与求偶识别；雌虫的触角、下颚须、下唇须、第8腹节和产卵器参与了产卵位置的找寻和探测。松墨天牛触角上总共有7种感器,下颚须和下唇须上分别着生有相同的6种感器,腹部末节和产卵器上共有5种感器；观察并记录了感器基座、基座下神经结构、感器壁开口的结构(顶孔、壁孔、辐射状通道)、外树突节的多种树突结构和部分神经细胞结构等重要感器特征；分析感器的超微神经结构显示着生于不同位置的感器具有不同的功能,总体包括机械感受、嗅觉化学感受、接触性化学感受(味觉感受)以及温湿度感受。6、观察明确了寄生性天敌花绒寄甲和捕食性天敌莱氏猛叩甲触角上感器的形态和超微结构：花绒寄甲雌雄虫触角上的感器数量少、种类简单；感器的超微结构显示毛形感器和锥形感器淋巴腔中具有树突,具有化学感受的功能。莱氏猛叩甲触角具有明显的雌雄二型现象；感器种类有刺形感器、锥形感器、毛形感器、耳形感器、腔锥形感器、钟形感器和Bohm’s鬃毛,分析这些感器的超微神经结构显示其功能包括机械感受、嗅觉化学感受、接触性化学感受(味觉感受)以及温湿度感受。综上所述,本文研究了混交林内复杂化学信息中植物-植食性昆虫-天敌三者之间的关系：(1)松墨天牛与寄生性天敌花绒寄甲可同时被发病后衰弱黑松的挥发性物质3-carene,limonene,α-pinene所吸引,并同时被阔叶树所挥发的cis-3-hexen-l-ol所吸引；松墨天牛被吸引产卵的同时,花绒寄甲也可被吸引前往寻找寄主天牛。(2)花绒寄甲可被广谱植物挥发物nonanal和octanal所吸引,增加了其找到除松墨天牛外其他合适寄主的几率。(3)松墨天牛对6种阔叶树的挥发物即有趋避反应也有趋向反应；这些树种的挥发物可以在一定程度上干扰松墨天牛的寄主找寻行为,说明混交松林内的化学信息多样性可以提高其对松墨天牛的抵御性。更多还原

【Abstract】 Pine wood wilt is a devastating epidemic disease in China that infests pine trees in coniferous forests caused by the pine wood nematode (Bursaphelenchus xylophilus). Short-distance natural diffusion of pine wood nematode disease primarily depends on the flight and feeding of its vectors, the Japanese pine sawyer beetle (Monochamus alternatus Hope)(Coleoptera:Cerambycidae). Adult M. alternatus beetles emerge in early summer. They feed on fresh branches of healthy trees until they are sexually mature. The beetles copulate repeatedly and then females lay their eggs under the bark of weak or stressed host trees. The parasitoid beetle Dastarcus helophoroides (Fairmaire)(Coleoptera:Bothrideridae) is an important parasite of longicorn beetles (Cerambycidae). Tetrigus lewisi Candezeis is a predatory click beetle that can feed on M. alternatus. In this research we focused on the volatiles released by pines in different infection stages, volatiles released by other broad-leaf trees (Cinnamomum camphora, Liquidambar formosanat, Broussonetia papyrifera, Dalbergia hupeana, Albizia julibrissin and Sassafras tzumu) in the same plant community; ecological niche of larvae M. alternatus and its nature enemies on pines in different infection stages; as well as electroantennogram and behavior responses of M. alternatus and D. helophoroides to the above volatiles. Main conclusions are as follow:1. The ecological niche and the population distribution of larvae M. alternatus and its nature enemies on P. massoniana and P. thunbergii in different infection stages were investigated:no sign of M. alternatus was observed on pines in the HW stage. The current year oviposition scars were observed on pines in the IP stage, while ecological niche of the current year larvae was low. A great number of the current year oviposition scars were observed on pines in the EP till the PP stages, and ecological niche of the larvae reached maximum within those stages. The ecological niche of M. alternatus was significantly related with the ecological niche of T. lewisi. No D. helophoroides was found on the30infection pines that were investigated.2. Volatiles released by P. massoniana and P. thunbergii in different infection stages were collected and measured:total mass of the volatile decreased as the pines became weaker, it was extremely few at the stages of PP and TP. At the stages of IP and EP, the mass of limonene and3-carene released by the masson pines and leaves of the black pines showed increasing trend, same with a-pinene released by stem of the black pines. After infection with PWN, the major volatile compounds of stems of P. massoniana and P. thunbergii included α-pinene, β-pinene, limonene and3-carene, the major volatile compounds of leaves and branches were a-pinene, β-pinene, limonene,3-carene and β-phellandrene. Within the volatiles released by stems of the pines in HW to MP stage, the percentage of α-pinene increased, the percentage of β-pinene decreased, the percentage of limonene,3-carene increased then decreased; while within the volatiles released by leaves and branches of pines from the HW to MP stage, the percentage of3-carene and β-pinene increased, the percentage of a-pinene decreased, the percentage β-pinene remained.3. EAG responses and behaviour orientation of M. alternatus towards volatiles released by host and non-host trees were tested:the following compounds elicited positive responses in both EAG and behaviour responses,3-carene,(R)-(+)-a-pinene,(S)-(-)-a-pinene, camphene,(R)-(+)-limonene,(S)-(-)-limonene, β-phellandrene, β-myrcene (released by both infection black pine and broad-leaf trees), linalool, cis-3-hexene-l-ol and methyl salicylate (released by broad-leaf trees). Female beetles showed positive responses to α-terpinene,(-)-α-cedrene (released by infection black pine) and (-)-β-caryophyllene (released by both) in behaviour tests. Both genders showed repellent action towards camphor, octanal, ocimene and α-farnesene (released by broad-leaf trees). Results indicted that volatiles from both host and non-host tress could affect the behaviours and actions of M. alternatus.4. The electroantennogram (EAG) technique and a dynamic two choices olfactometer were used to measure the responses of male and female D. helophoroides to the selected synthetic host-related plants volatiles. Significant dose-dependent EAG responses were elicited by nonanal, octanal cis-3-hexen-l-ol (released by broad-leaf trees),3-carene,(R)-(+)-α-pinene,(S)-(-)-α-pinene,(R)-(+)-limonene and (S)-(-)-limonene released by both infection black pine and broad-leaf trees) in both genders. D. helophoroides were attracted by nonanal, octanal cis-3-hexen-l-ol,3-carene,(R)-(+)-α-pinene,(S)-(-)-α-pinene,(R)-(+)-limonene and (S)-(-)-limonene at certain concentration, and repelled to cis-3-hexen-l-ol at the concentration of10-1mg/mg in the behavior bioassay. The results of this study have represented an initial attempt to demonstrate the electrophysiological sensitivities and orientation behaviors of D. helophoroides to the selected host-related plant volatiles.5. Mate recognization and oviposition site detection of M. alternatus were observed and focused on the major functional sensilla involved:antenna, maxillary and labial palps played key roles in mate recognization; while antenna, maxillary and labial palps, the8th abdomen together with the ovipositor all involved with the oviposition site detection behaviors. The morphology, typology and fine structures of sensilla located on antenna, maxillary palp, labial palp and ovipositor were observed systematically by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Seven types of sensilla were identified on the antenna, six types were found on the maxillary and labial palps, and five types were found on the8th abdomen and ovipositor. Important sensillar characters such as forms of the socket, connections with the antenna cuticle, openings of the sensillar cuticle (pores, spoke channels or uniporous tip) and varied dendrite structures in the outer dendritic segment were observed. The putative functions including mechanoreception, chemoreception and hygro-or thermo reception of those sensilla were compared and discussed.6. The antennal morphology and sensillar ultrastructure of D. helophoroides and T. lewis were observed:four types of antennal sensilla were found on D. helophoroides; ultrastructural studies revealed porous structures on the cuticle wall and dendritic branches in the inner lumen of Tr.l, Tr.2, Ba.l, and Ba.2, thereby suggesting chemoreception function. Eight types of sensilla were observed on the antennae of T. lewisi, including sensilla chaetica, sensilla basiconica, sensilla trichodea, as well as sensilla auricillica, sensilla coeloconica, sensilla campaniformia, sensilla styloconica and Bohm’s bristles; the chemoreception, mechanoreception and thermo-/hygro-reception functions were deduced from fine structures on the cuticular walls and the dendrites of different sensilla types.The relationship among plants, herbivorous insects, and its natural enemies in the aspect of semiochemical communication in mingled forest have been studies in this thesis.(1) M. alternatus and its parasitoid beetle D. helophoroides could both be attracted by volatiles released by infected black pines (3-carene, limonene, a-pinene), and a common green leaf volatile-cis-3-hexen-l-ol, thus D. helophoroides could locate M. alternatus by approaching the above chemicals.(2) D. helophoroides could also be attracted by nonanal and octanal which released by lots of plants, that increased the possibility of successful parasitism on other hosts.(3) M. alternatus could recognize and response as attracting or repellenting towards different compounds released by6species of non-host broad-leaf trees; those volatiles would interfere the host location of M.alternatus; the mingled pine forest with complex semiochemical information would possess higher resistance to possible damage from M.alternatus.更多还原