Analysis Of MtDNA Sequences Of Gypsy Moth In Different Areas Of China And Breeding Technology Optimization

The gypsy moth,Lymantria dispar(Linnaeus,1758)(Insecta:Lepidoptera:Erebidae:Lymantriinae),is one of the most important agricultural and forest insect pests.The species is divided into two subtypes:European gypsy moth and Asian gypsy moth.Among them,the Asian gypsy moth has long been thought to pose a greater threat to the world due to its larger host species and greater female flight ability.In order to better understand the genetic structure of AGM,especially the population structure of Chinese gypsy moth,this paper makes an in-depth analysis on the mitochondrial DNA sequence fragments of gypsy moth in different regions.Then,the artificial feeding technology of gypsy moth was optimized.The main results are as follows:1.Based on the barcoding study of mitochondrial COI gene of gypsy moth,we constructed a molecular phylogenetic tree that showed that the samples of Chinese gypsy moth were divided into three groups:the first group(Guizhou,Xifeng)was separated from Asian and European gypsy moths and formed a independent group.The second group contains most of China's geographic populations and converges on the first cluster of Asian gypsy moths in the phylogenetic tree of the world's gypsy moth.Samples from Zunyi,Guizhou and Chengdu,Sichuan formed a third group and aggregated to the second cluster containing the United States and European populations.The clustering study of geographical populations of the same gypsy moth is consistent with the previous results of the research group.The above results showed that the Chinese gypsy moth population has a wide range of genetic variation characteristics.2.We sampled five mitochondrial protein-coding genes(ND2,ND6,ATP6 and ATP8)extracted from 38 populations worldwide and reconstructed a matrilineal genealogy of gypsy moths using bayesian method.The results showed that the Chinese gypsy moth populations are separated into three different genetic clusters:China I represents common AGM closely related to moths from other Eastern Asian countries;China II forms a sister group of the common AGM clade;China III,IV is nested within the clade of Western Europe and North America.In addition,our study confirmed that the recently discovered Iranian genotype consist of an independent of genetic lineage.3.The effects of different artificial feeding methods on biological indicators were studied with Asian gypsy moths and European gypsy moths.It demonstrates that feeds boiled by Steam Kettle significantly reduced the larvae's susceptibility,increased larval rate and weight.The treatment of newly hatched larvae with gauze can increase the survival rate of early-larvae and reduce the incidence of infection.The results showed that the larvae growth in the drilled jelly cup is best,and the pupation rate are significantly higher than that of the square petri dish and the air window jelly cup.