Preliminary Study On Sex Pheromone And Plant Volatiles Of Diaphania Angustalis Snellen(Lepidoptera: Pyralidae)

Diaphania angustalis Snellen is one of the important pests attacking Alstonia scholaris in southern of C hina.Alstonia schalaris is a famous street tree,which plays a very important role in city afforestation.Besides,there are many alkaloids in A.schalaris plant leaves and it has a good effect on the treatment of cancer.The D.angustalis larvaes eat mesophyll,which can cause the canopy of branches bare even death.The reproductive biological characteristics of D.angustalis was observed,and two compounds of the sex pheromone in crude extract get by gas chromatography-electroantennographic detection(GC-EAD)and gas chromatography-mass spectrometry(GC-MS)in this paper.In addition,the volatiles of four different A.schalaris plants were collected by headspace volatiles collection method,then the collected volatile extracts were analyzed to identify volatile compounds attractive to D.angustalis moths by using GC-EAD and GC-MS.The main research results were as follows:The adults emergence,calling and mating behavior of D.angustalis were observed under laboratory conditions of 25-28 °C,12 L : 12 D photoperiod and 75-80% RH.Result revealed that D.angustalis moths emerged all day.Peak emergence of males and females were recorded on 22:00 to 1:00 hr.The virgin females calling behavior was characteristic with extension of the ovipositor to expose the pheromone glands and only observed during the scotophaphase.The peak of greatest calling activity occurred on the 3-d-old at 5 h into the scotophase.Most of the moths started mating from 2-d-old after emergence.Moths mating behavior varied by age,with an increasing proportion of copulation from 2 to 3-d-old and gradually decreasing from 4 to 5-d-old.And the number of mating moths increased from 3hr to 5 hr after lights-off and then decreased.The female sex pheromone crude extract of D.angustalis were examined by gas chromatography-electroantennographic detection(GC-EAD)and gas chromatography-mass spectrometry(GC-MS),there were E10E12-16:Ald and E11-13:Ac.The electroantennogram(EAG)analysis of D.angustalis moths to young leaves of resistant plants A.schalaris,old leaves of resistant plants A.schalaris,young leaves of ordinary plants A.schalaris and old leaves of ordinary plants A.schalaris,we found that the antennae reaction is strong to ordinary plants A.schalaris.There is no difference with the male and virgin female insects.In this study,headspace volatiles from six plants including young leaves of resistant plants A.schalaris,old leaves of resistant plants A.schalaris,young leaves of ordinary plants A.schalaris,old leaves of ordinary plants A.schalaris,the pest plant,the volatiles of D.angustalis larvae were analysed by GC-MS technique.At last,we identified 18 compounds,20 compounds,19 compounds,20 compounds,23 compounds and 13 compounds.Besides,there are a variety of compounds as a common component of several plant volatiles,and the terpenoids volatiles in insect pests increased obviously.The sensitive reaction of D.angustalis moths antenna to the methylene dichloride extracts from kinds of plant volatiles was analyzed by GC-EAD.Five compounds were identified in inducing GC-EAD responses of young leaves of ordinary plants A.schalaris,containing 1R-alpha-Pinene,Benzaldehyde,2-ethyl-,longifolene,methyl laurate,triethyl citrate.GC-EAD responses of young leaves of resistant plants A.schalaris.Seven compounds were identified in inducing 1R-alpha-Pinene,Z-3-Hexenyl acetate,Limonene,terpilenol,Ethanone,1-(4-ethylphenyl),Methyl tetradecanoate,Hexadecanoic acid methyl ester.GC-EAD responses of pest plants A.schalaris.four compounds were identified in inducing 1R-alpha-Pinene,cis-3-Hexen-1-ol,1,3,6-Octatriene,3,7-dimethyl,1-caryophyllene.GC-EAD responses of Mirini Ashmead to the volatiles of D.angustalis larvae.two compounds were identified in inducing 1R-alpha-Pinene and Hexadecane.These data provided a basic information for semiochemical based D.angustalis pest monitoring and management,and they could provide a reference for further studies of moths behavioral rhythms.