Diffusive And Reproductive Abilities Of Cold Region Entomopathogenic Nematodes And Holotrichiadiomphalia Bates

Entomopathogenic nematode (EPN) is one of international research focuses as abiological agent. Reproductive capacity and applied environment are always theproblems hindering application and control efficiency of EPN. Steinernemacarpocapsa-All（Sc-All）and Heterorhabditis bacteriophora-Hrbb（Hb-Hrbb）, twonematode stains applied mainly at present, were used to study the effect of productivetechnology, storage method and environment on diffusivity of EPN. An easy andefficient storage condition and manageable environment were expected. Thisresearch will provide basic information for EPN application, and has significantacademic and practical value on biological and ecological research of EPN.Lepidopterous larvae Noctuidae and Galleria mellonella were infected by Sc-Alland Hb-Hrbb to study reproductive capacity of EPN in different hosts. Both Sc-Alland Hb-Hrbb reproduced in the two hosts, and Sc-All presented higher reproductivecapacity than Hb-Hrbb. The daily output of Sc-All and Hb-Hrbb was lower inProdenia litura than in Galleria mellonella, but collective time was longer inLepidoptera noctuid and Galleria mellonella. The total output of nematode was notsignificant different inLepidoptera noctuid and Galleria mellonella. Hb-Hrbb wasstored in mine soil, sponge and water to study the optimum storage agent andcondition at three temperatures. Hb-Hrbb had longest storage time and highestactivity when it with1.0×105IJs/ml was stored in mine soil at10℃, and Hb-Hrbbsurvived two months and still maintained high activity. The diffusivity of EPN wasstudied in sandy pillar with4moisture contents,3temperatures and5values of pH,and soybean, radish and chive were planted in sandy pillar as different planttreatments. EPN diffused freely at vertical and horizontal directions in the conditionwith15%moisture content and neutral soil at25℃. EPN distributed around plant roots, and EPN was affected by plant roots, but the effect was not significant amongthree plants. Juveniles2and3of grub were infected by Hb–Hrbb, Heterorhabditisbacteriophora-06（H06）and Steinernema glasei（Sg）to study the pathogenicity ofEPN. The results showed that Sg had best control efficiency among three nematodestrains, and the control efficiency was not significant on Juveniles2and3ofHolotrichiadiomphalia Bates. EPN showed best control efficiency in the soil with17%moisture content at25℃.