Population Dynamics And Community Characteristics Of The Main Insect Pests And Their Natural Enemies On Salvia Miltiorrhiza In Liaocheng City

Salvia miltiorrhiza is traditional Chinese herbal medicine with high medicinal and economic value in China.During recent years,the planting of Chinese medicinal herbs were attached to great importance in Liaocheng City,Shandong province and the planting areas of Salvia miltiorrhiza were getting more and more.The population dynamics of major insect pests and their natural enemies on Salvia miltiorrhiza were investigated systemically.Based on the investigation,the community structure of major insect pests and their natural enemies on Salvia miltiorrhiza was analyzed.The carrying loads of major insect pests and their natural enemies on Salvia miltiorrhiza and the corelationship between them were analyzed by the multivariate statistical analysis methods,i.e.the principal componengt analysis,the canonical correlation analysis.Meanwhile the temporal patterns of communities of major insect pests and their natural enemies were analyzed by optimal sorting method.All the research results provided scientific theoretical basis for carrying out green control tactics for the insect pests on Salvia miltiorrhiza to ensure the sustainable production of Salvia miltiorrhiza.The main research results were as follows:1.The population dynamics of major insect pests（aphids,phytophagous bugs,Helicoverpa armigera,Bemisia tabacci,orthopterous insects）and their natural enemies（aphidiids,lacewings,ladybird beetles,predatory bugs,Campoletis chlorideae and spiders）on Salvia miltiorrhiza were investigated and analyzed systemically.The main natural enemies had followed the occurrence of the main insect pests well.2.According to the investigaton statistics,53 species of major insect pests and natural enemies on S.miltiorrhiza were found,which contained 22 species of insect pests and 31species of natural enemies,accounting for 41.5%and 58.5%of 53 species,respectively.The relative abundances of major insect pests and natural enemies on S.miltiorrhiza were analyzed.Among the major insect pests,the relative abundances of aphids,Bemisia tabacci,Helicoverpa armigera and orthopterous insects were higher,accounting for 25.57%,41.03%,4.83%and 3.63%,repectively;the relative abundances of lacewings,ladybird beetles,predatory bugs and spiders among the predatory natural enemies were higher,accounting for5.83%,3.61%,1.27%and 1.26%,repectively;the relative abundances of aphidiids（important parasitoid of aphids）and Campoletis chlorideae（one species of important parasitoids of Helicoverpa armigera）among the parasitic natural enemies were higher,accounting for1.52%and 0.54%,repectively.3.The population dominance of the major insect pests and natural enemies on S.miltiorrhiza were analyzed,The dominant species of insect pests on S.miltiorrhiza were one species of brown aphid（an unidentified species）,Tetranychus truncates,Helicoverpa armigera,Bemisia tabacci,Halticus minutus,Pyrausta phoenicealis and Nysius ericae,respectively;the dominant species of natural enemies of aphids were aphidiids,Harmonia axyridis,Chrysopa pallens,Chrysoperla sinica,Geocoris pallidipennis,respectively;the dominant species of natural enemies of Helicoverpa armigera were Campoletis chlorideae and spiders,respectively;the dominant species of natural enemies of phytophagous bugs and orthopterous insects were many spiders,respectively.4.Community characteristics indices such as species richness,ecological dominance,diversity and evenness in the main insect pest and natural enemy communities on S.miltiorrhiza were analyzed.The richness and diversity of the insect community were higher during the most time of the growing stages of S.miltiorrhiza in the field.The degrees of community diversity were affected by the growth stages of S.miltiorrhiza,surrounding habitat and climate factors and the interactons between the main insect pests and their natural enemies.5.The main insect pests and their natural enemies and the corelationship between them were analyzed by the principal component analysis and the canonical correlation analysis.Among the main insect pests and their natural enemies,the corelationship degrees between aphids and aphidiids,between Bemisia tabacci and predatory bugs,between Helicoverpa armigera and Campoletis chlorideae,between orthopterous insects and spiders,were higher.6.The temporal patterns of the main insect pest and natural enemy communities on S.miltiorrhiza were divided into four consecutive temporal periods by using the optimal sorting method,i.e.from May 9^thh to June 11^th,from June 19^thh to July 5^th,from July 15^thh to July 31^st,from August 9^thh to October 12^th).The species and the occurrence characteristics of insect pests and their natural enemies on S.miltiorrhiza during the four periods were analyzed.