Population Dynamics And Community Characteristics Of The Main Insect Pests And Their Natural Enemies On Four Medicinal Plants

Four traditional medicinal plants,Lonicera japonica,Chaenomeles sinensis,Dendranthema morifolium and Salvia miltiorrhiza in China,have high medicinal and economic value.The ecological principles and methods were used to analyze population dynamics and community characteristics of major insect pests and their natural enemies on four traditional medicinal plants.Meanwhile the temporal patterns of the sequential samples of the communities of major insect pests and their natural enemies were analyzed by optimal sorting.All the researches provided scientific theoretical basis for developing green control tactics for the insect pests on four traditional medicinal plants to ensure green and sustainable production of four traditional medicinal plants.The main research results were as follows:1.The correlations of the main insect pests to their natural enemies on four traditional medicinal plants were analyzed.The main insect pests on L.japonica included aphids?Semiaphis heraclei and Aphis gossypii?,Heterolocha jinyinhuaphaga,Arge similes and phytophagous true bugs,and their natural enemies contained ladybirds,lacewings and spiders.The main insect pests on C.sinensis included Myzus persicae,Ricania speculum,Grapholita molesta and Phalera flavescens,and their natural enemies contained spiders,ladybirds and lacewings.The main insect pests on D.morifolium included aphids?Macrosiphoniella sanborni and A.gossypii?,leafhoppers?Empoasca flavescens and Cicadella viridis?,Phytoeciarufiventris,Diarthronomyiachrysanthemi,Atractomorphasinensisand phytophagous true bugs,and their natural enemies contained ladybirds,spiders and lacewings.The main insect pests on S.miltiorrhiza included aphids?A.gossypii and one brown aphid?an unidentified species??,leafhoppers?E.flavescens and C.viridis?,Halticus minutus,Bemisia tabaci,A.sinensis and lepidopterous insect pests?Helicoverpa armigera,Pyrausta phoenicealis and Ascotis selenaria?,and their natural enemies contained ladybirds,spiders,lacewings and parasitic wasps.The results showed that there were time lags between the natural enemies and major insect pests on four medicinal plants,which showed some following phenomena and took combined control effect to insect pests.2.According to the survey statistics,there were 71 species?including Fruticicolidae?of major insect pests and natural enemies on L.japonica that belonged to 43 families,12 orders,3 classes and 2 phyla,which contained 42 species of insect pests and 29 species of natural enemies.There were 51 species?including Fruticicolidae?of major insect pests and natural enemies on C.sinensis that belonged to 34 families,11 orders,3 classes and 2 phyla,which contained 35 species of insect pests and 16 species of natural enemies.There were 70 species?including Fruticicolidae?of major insect pests and natural enemies on D.morifolium that belonged to 44 families,12 orders,3 classes and 2 phyla,which contained 40 species of insect pests and 30 species of natural enemies.There were 60 species of major insect pests and natural enemies on S.miltiorrhiza that belonged to 35 families,10 orders,2 classes and 1phyla,which contained 30 species of insect pests and 30 species of natural enemies.3.The relative abundances of major insect pests and natural enemies on four medicinal plants were analyzed.The results indicated that the insect pests on L.japonica were mainly lepidopterous larvae and aphids,and their natural enemies included ladybirds,spiders and lacewings.The insect pests on C.sinensis were mainly lepidopterous larvae and aphids,and their natural enemies contained spiders,ladybirds and lacewings.The insect pests on D.morifolium were mainly leafhoopers and aphids,and their natural enemies included ladybirds,spiders and lacewings.The insect pests on S.miltiorrhiza were mainly aphids and phytophagous true bugs,and their natural enemies contained ladybirds,lacewings,spiders and parasitic wasps.4.Based on the dominance index,the dominant species of insect pests and natural enemies on four medicinal plants were analyzed.The dominant species of insect pests on L.japonica were S.heracleid and H.jinyinhuaphaga;the dominant species of their natural enemies were Ebrechtella tricuspidata,jumping spiders,Harmonia axyridis and Propylaea japonica.The dominant species of insect pests on C.sinensis were M.persicae,G.molesta and P.flavescens;the dominant species of their natural enemies were H.axyridis,Chrysoperla nipponensis and jumping spiders.The dominant species of insect pests on D.morifolium were A.gossypii,E.flavescens and C.viridis;the dominant species of their natural enemies were E.tricuspidata and jumping spiders.The dominant species of insect pests on S.miltiorrhiza were A.gossypii and the brown aphid?an unidentified species?;the dominant species of their natural enemies were E.tricuspidata,Coccinella septempunctata,Apanteles sp.and aphidiid.5.Community characteristics indexes such as species abundance,ecological dominance,diversity and evenness in the main insect pest and natural enemy communities on four medicinal plants were analyzed.The results showed that the growth stages of four medicinal plants,environmental conditions and dominant pest populations on L.japonica,C.sinensis,D.morifolium and S.miltiorrhiza were the main factors affecting the changes of community structure characteristics.6.The temporal patterns of the main insect pest and natural enemy communities on L.japonica,C.sinensis,D.morifolium and S.miltiorrhiza were divided into four time periods by using the optimal sorting method(L.japonica:from April 22ⁿdd to July 1^st,from July 8^thh to August 26^th,from September 2ⁿdd to September 22^nd,from September 29^thh to October 28^th.C.sinensis:from April 22ⁿdd to May 13^th,May 20^th,from May 27^thh to June 10^th,from June 17^thh to October 7^th.D.morifolium:from April 22ⁿdd to May 27^th,June 3^rd,from June 10^thh to June 17^th,from June 24^thh to October 28^th.S.miltiorrhiza:from April 22ⁿdd to July 8^th,from July 15^thh to August 5^th,from August 12ⁿdd to September 22^nd,from September 29^thh to October 28^th).The occurrence characteristics of insect pests and natural enemies during the various time periods on L.japonica,C.sinensis,D.morifolium and S.miltiorrhiza were analyzed with the growth stages of medicinal plants and environmental conditions.