Glucose Oxidase Activity Of Dioryctri Pryeri,Ragonot Larva Againinst To Defense Of Host

Pine coneworm, Dioryctria pryeri Ragonot (Lepidoptera:Pyalidae), is an important insect pest of coniferous cones and shoots in China. Research of the relationship of pests and host has an very important significance in effective control of the dangers of cones pest and realize the efficient production and natural forest regeneration. Because, Gravitarmata margarotana (Heinemann) first feeding host cones, which induce Dioryctria pryeri Ragonot to trend pest cones to lay eggs and feed, that is called induced negative defense or induced susceptibility. Dioryctria pryeri Ragonot against to defense of negative defense induced by Gravitarmata margarotana is also the main content. Because insect herbivores adapt or overcome to plant induced defense which means pests adapt to pests resistant transgenic plants, it has the vital significance and is also the basic of further discussed pest inducted negative defense phenomenon.The study use spectrophotometer method to test the salivary glucose oxidase activity of Dioryctria pryeri Ragonot Pests larva, The result show that salivary glucose oxidase activity increases very significantly from3to4to5instar; glucose oxidase activity reaches the highest the second day of5instar (taking active period); The old larve larvae before pupa (no longer taking) is Down to a minimum. Namely glucose oxidase activity and larvae feeding activity are closely related and will increase as insect age increase. To test feeding different parts of host larva to influence of glucose oxidase activity, we measure glucose oxidase activity of4process scenarios of branches, One larva in one cone, symbiosis with G.maigarotana and more larvae in one cone, found glucose oxidase activity of taking active period larvae of the same instar in different parts are different and all show that glucose oxidase activity of larva symbiosis with Gmaigarotana is the highest, glucose oxidase activity of larva in branches is the lowest, glucose oxidase activity of larva in cones is in the middle.GC-MS were used to determine the change of terpenoid compounds in the glucose oxidase trained cones and current year branches of Pinus tabulaeformis Carr. In the content of monoterpene, sesquiterpene and diterpene of the trained cone were higher than contrast. This suggests that the glucose oxidase can inhibit the host chemical defense material.To further validation Dioryctria pryeri Ragonot larve can overcome the host defense reactions, adopt microfluorometric method and the method of phosphate determinationusing ascorbic respectively to measure RNA and P content of the Dioryctria pryeri Ragonot larva which are the same instar but feed different host parts(cones and current year branches). Because Insects growth rate and RNA content of and P content of larvae body are highly coupled. The result display differences of the content are not statistical significant. That is taking different materials of the host has no significant influence on growth rate of Dioryctria pryeri Ragonot larva. The growth rate of Dioryctria pryeri Ragonot parasited on one cone with Gravitarmata margarotana has no significant difference with the Dioryctria pryeri Ragonot parasited on the cones without Gravitarmata margarotana. This testify Dioryctria pryeri Ragonot larva can through restraining the host defense reactions to overcome negative defense induced by Gravitarmata margarotana. The result display differences of the RNA and P content are not statistical significant. That is taking different materials of the host has no significant influence on growth rate of Dioryctria pryeri Ragonot larvae. This Further Illustrates Dioryctria pryeri Ragonot larva can adjust glucose oxidase activity to make sure that food quality can not affect the growth and development of the larva.