【作者】 李凯；

【导师】 陈建明； 陈列忠；

【作者基本信息】 杭州师范大学 ， 生态学， 2012， 硕士

【摘要】 本文主要研究了褐飞虱对同类昆虫遇险时释放的挥发物的行为反应,分离测定了这种挥发物的主要成分,并以这种挥发物的溶剂萃取物来检测其对褐飞虱的行为影响。其研究结果如下：(1)褐飞虱对同类昆虫遇险释放挥发性物质的行为反应：利用“Y”型嗅觉仪测定了褐飞虱对同类昆虫被草间小黑蛛捕食时产生的化学物质的行为反应,以此验证褐飞虱在遭遇危险时是否产生向同类报警的化学信号。结果表明,褐飞虱若虫对草间小黑蛛释放的挥发性化学物质无逃避反应,而对同类昆虫遭遇草间小黑蛛捕食时释放的挥发性物质则表现出明显的逃避行为,其中1龄褐飞虱若虫有显著的逃避反应,2-3龄若虫有极显著的逃避反应,4-5龄若虫无明显反应。说明褐飞虱低龄若虫在遭遇天敌捕食时会释放挥发性化学物质,产生报警行为,给同类昆虫一个危险警示信号,但褐飞虱高龄若虫的报警行为不明显,推测其原因可能是草间小黑蛛对褐飞虱高龄若虫的捕食能力较弱或者是褐飞虱高龄若虫被捕食时不产生报警信号。(2)褐飞虱遇险释放的挥发性物质的分离与鉴定：利用PDMS、CAR/PDMS柱材料的固相微萃取法分别萃取褐飞虱自身释放的挥发性物质和褐飞虱遭遇草间小黑蛛捕食时释放的挥发性物质,并用GC-MS进行分析。结果表明,褐飞虱在遭遇草间小黑蛛捕食时产生了一种新的挥发物,通过与已知化合物的质谱图比对,发现与(E)-2-已烯醛相似,推测这种化合物具有与(E)-2-已烯醛相似的化学结构,而且能够在分子之间发生反应,生成分子量较高但不稳定的化合物。已知(E)-2-已烯醛化合物在蝽象、蟑螂等昆虫的报警信息素都有发现过,因此这种化合物很可能对褐飞虱也有报警作用,其实际结构还需要进一步的研究。(3)褐飞虱遇险产生报警信息素的验证：比较研究了褐飞虱报警信息素的提取条件,明确了乙酸乙酯对褐飞虱遇险释放的挥发性物质有较好的提取效果,在500mL味源瓶中放入300头褐飞虱2-3龄若虫比较适宜,提取时间连续提取3小时以上,提取温度在15-25℃左右。用“Y”型嗅觉仪检测这类萃取物对褐飞虱2、3龄若虫的行为影响。结果表明,该乙酸乙酯提取物能引起褐飞虱2-3若虫有显著的逃避行为,这验证了褐飞虱遭遇天敌如草间小黑蛛捕食时能释放向同类昆虫报警的化学信息素,而且这类化合物易溶于乙酸乙酯,其挥发性也比乙酸乙酯小。更多还原

【Abstract】 This paper was aimed to study alarm behavior and alarm pheromone of BPH。 Y-tube olfactometer was used to examine whether volatiles released by BPH being preyed on by dwarf spider could elicited escape behavior of colonymates; Then, the volatiles were isolated and analysed. At last, solvent extract of the volatiles was examined with Y-tube olfactometer for its effect on BPH. The results were as follows:(1) Behavioral response of the brown planthopper, Nilaparvata lugens, to the volatile substance of the same kind of insects attacked by dwarf spider, Erigonidium graminicolumBehavioral response of the brown planthopper (BPH), Nilaparvata lugens, to the same kind of insects attacked by dwarf spider, Erigonidium graminicolum, was studied with Y-tube olfactometer in order to verify whether the alarm signal was released to the same kind of insects when BPH attacked by their natural enemies. The results showed that no escape response of BPH nymphs to the chemicals of E. graminicolum, significant escape response of the1st instar nymphs, very significant escape response of the2nd to3rd instar nymphs and no obvious response of the4th to5th to the volatile substance released by the same kind of insects when attacked by E. graminicolum. It was conjectured that E. graminicolum may has weak predatory ability on older nymphs of BPH, or older nymphs may not release alarm signal when they were attacked by E. graminicolum.(2) Isolation and analysis of the volatile substance released by BPH indangrousVolatile substances released by BPH only and BPH attacked by E. graminicolum were extracted with SPME material included PDMS and CAR/PDMS. Empty odor source and BPH only was used as control. Extract was analyzed with GC-MS. The result showed that new substance was released by BPH coexisting with E. graminicolum. The new substance was presumed to be a seven-carbon acyclic compound with an alkenyl and a carbonyl group, according to the mass-spectrogram. In addition, some components were both detected in volatiles of BPH only and BPH coexisting with the spider. They may be contaminant, or alarm pheromone produced as a result of the transmission from plant to odor source, or other pheromones of BPH. Their origin and function should be still determined by further study. (3) Verification of alarm pheromone released by BPH in dangrousBy studying the extract condition of alarm pheromones of BPH, we found a good extract effect of the volatiles extracted with ethyl acetate solvent, a reasonable number of2nd to3th instar nymphs of BPH (300BPH in500mL taste source bottle), suitable extract time for continuous three hours, and extract temperature is15-25℃. Effect of this extract to2nd to3th instar nymphs of BPH was tested with Y-tube olfactometer. The result showed that ethyl acetate extract induce significantly the escape behavior of2nd to3th instar nymphs of BPH. Ethyl acetate solvent was proved to be most effective to extract the volatiles released by BPH, and it was verified that BPH could release alarm pheromones to the same kind of insects when they attacked by E. graminicolum. This compound dissolved in ethyl acetate solvent easily, and its volatile was less than ethyl acetate.更多还原