西藏飞蝗虫粪粗提物的成分分析及其活性测定

Abstract

Locusta migratoria tibetensis(Chen),a unique subspecies of migratory locust in Tibetan Plateau,has caused serious damage in recent years,and the study of its aggregation mechanism can be the basis for its ecological management.In this paper,we investigated the components of the fecal extract of this pest by gas chromatography-mass spectroscopy(GC-MS) and evaluated its bioactivity by a self-made Y olfactometer as well as electroantennograms.The results showed that the fecal extract bioactivities of different extract methods to solitary and gregarious fourth-instar nymphs differed,and that ethyl alcohol extraction was the best method for extracting fecal extracts of L.migratoria tibetensis.The bioactivity of fecal extracts increased with instars,and the gregarious adult locusts had the strongest bioactivity.The taxis ratio of solitary locusts to the fecal extracts of solitary and gregarious nymphs was more than that of gregarious locusts to the fecal extract of nymphs.In detail,we detected 35 components in the fecal extract of L.migratoria tibetensis by GC-MS,where we found that the main constituents were cyclohexanol,2,5-dimethyl pyrazine,2,6,6-trimethyl-2-cyclohexene-1,4-dione,nonanal,benzyl alcohol,(E)-3,7,11,15-tetramethyl-2-hexadedcen-1-ol,3-phenylbutan-2-ol,and 2,2′-methylenebis(6-tert-butyl-4-methylphenol).The components and their relative contents differed among the different developmental stages of fecal extracts.Adult female feces contained the most components,while that of solitary nymphs had the fewest.Some of the components of L.migratoria tibetensis were the same as the components of aggregation pheromone of Locusta magratoria manilemsis(Meyen).The electrophysiological responses of L.migratoria tibetensis to single artificially synthesized chemical compounds(concentration range 0—4 μL/mL) can be divided into three types.For the first type,the electrophysiological responses got the maximum value with the content of 2 μL/mL.For the second one,the electrophysiological responses to the same chemical compound differed among the developmental stages.And for the last type,the electrophysiological responses increased with the concentration of the compound.This paper reported the first study of the fecal extracts of L.migratoria tibetensis,however,further research is also needed to clarify the aggregation mechanism of this economically-important pest.