The Research About The Diversity And Community Composition Of Insects In Sweet Potato In Fuzhou Mountain

Sweet potato is a kind of food crops and main economic crops with high nutritional value in Fuzhou region.The amounts of crops is increased year by year.But in recent years,continuous cropping in Fuzhou north mountain fields,the decreasing varieties and the ill management of sweet potatoes which results in the sweet potatoes makes an bad influence on the production of sweet potatoes year by year.In this article,it mainly makes a research on the the diversity and community composition of insects in sweet potato in Fuzhou mountain in 2016.The results shows that during the growth period from May to November after the sweet potato seedlings,there are 2 classes,8 orders,34 families,38 species and 3252 quantities in the insect community of the sample field.The sweet potato pests account for 73.68%of the total species and 96.16%of the total individuals number.The natural enemy insect account for 21.05%of the total species and 5.63%of the total individuals number.The other kinds of insects account for 5.27%of the total of the species and 0.09%of the total individuals number.The number of the pests is much beyond the natural enemy insect among the insect community.The pests has dramatic impact on the insect community while the natural enemy is not.It cannot control the growth of pests in the community.Sweet potato pests mainly feed on leaves and the body of potatoes underground.The Braehmia macroscopa Meyrick and Anophia leucomelas(Linnaeus)are increasingly produced from July and August in defoliators.The cylas formicarius(Fabricius)and Holottichia sauteri Moser generate great growth among the underground drilling pests.The production of cylas formicarius(Fabricius)reaches a peak from August to September.Holottichia sauteri Moser grow rapidly from July to August.The natural enemy species mainly include Coccinellidae,Pheidole megacephala(Fabricius)and Araneida.According to sorting out the farmland data deliminator and using the analyzing of the DPS data,there are two kinds of dominant species in August,the number of varieties and individuals of insect community reaches the peak between August and September.And the insect community diversity index,evenness index and Simpson index are not high.The community stability is poor.It shows that August and September are the main seasons of pests growing.It is necessary to intensify the pest control during this period for the sweet potato growing.It also needs to take effective measures to prevent and control the growth of pests and pay attention to the introduce the natural enemy species.By promoting the richness and diversity of insect community,it can improve the stability of insect community.Furthermore,it can effectively control pest populations and promote the growth of potato.