The Occurrence Characteristics Of Rice Stem Borer In Xianyou County

The rice borer is one of the important insect pests of rice. In recent years, because the climate and the farming system changes, rice stem borer appeared many new characteristics. In this paper, according to the quantity of the rice stem borer trapped under the light, wintering characteristics, eclosion progress, recent field survey, discusses characteristic of rice stem borer in xianyou country, and analysis its reason. The research results on rice stem borer forecasting and prevention has important theoretical and guiding significance.1. Three community of the borer’s composition in xianyou conutry:in xianyou country, the Tryporyza incertulas is counted for66.98%of the insect quantity. Chilo suppressalis is the next closest sector at30.87%.then Sesamia inferens is counted for2.15%of the insect quantity from1996to2013.From2000to2010, Chilo suppressalis has obvious rise. Judging from the average amount of trapped, Chilo suppressalis be trapped from30.87%of the average annual to46.88%in2013. Look from rice pile wintering borer proportion, Tryporyza incertul as accounts for76.34%to55.43%, Chilo suppressalis increased from22.37%to22.37%. In terms of the structure of different years borer insect, Chilo suppressalis proportion rising number is proportional to the diversity of crop planting structure, Lepidoptera insect proportion changes have close relationship with rice varieties layout and early rice seeding time.2. Three stem Lepidoptera larvae overwintering period: from2006to2013, in the ove r-wintering stage, Lepidoptera is given priority to with Tryporyza incertulas, followed by Chilo suppressalis, Sesamia inferens accounts for only a few, they are in proportio n to the total amount of insect were75.5%,22.3%and2.19%. Seen from the differe nt overwintering places, three borers mainly larvae in rice pile, followed by rice straw and winter crop,accounts for98.9%,0.18%and0.91%. A large amount of residual ri ce field pile is an important factor of Lepidoptera harm happen next year.3. Lepidoptera insect growth in xianyou country: months light trap quantity growth dynamic into unimodal type, most light moth amount in July, the second is in august and June. To the second generation of moth, the largest amount of harm is the most serious, the third generation times, the first generation is less. The first generation of moth occurred roughly march to may, the height for the mid to late april; The second generation of moth occurred roughly June to August, the height for mid to late July. The third generation of Lepidoptera for august and september, the height in the middle of september.4. Lepidoptera sex ratio:From the light trap quantity, Chilo suppressalis females than the highest for the1-0.48. Tryporyza incertulas females than the highest for the1-0.2. Looked from the overall, Chilo suppressalis male ratio is higher, Sesamia inferens times, Tryporyza incertulas is the lowest moth. But the moth’s first generation of adult eclosion male and female proportion is1-0.52.5. Lepidoptera wintering features in xianyou country:Chilo suppressalis and Sesamia inferens wintering in aboveground rice pile is given priority to, mainly Tryporyza incertulas mainly in rice pile of wintering underground part of the organization. There have5.59Lepidoptera in plexus, overwintering mortality1.53%on average. Chilo suppressalis in the age of3to4and5-6age overwintering,6.85%and93.15%respectively, mainly in the near-surface wintering in about10cm rice pile stem; Tryporyza incertulas by only the old and adult larvae overwintered by winter, mainly in the underground part of rice pile wintering in the organizations. Have a small amount of Chilo suppressalis wintering in the straw.6. Lepidoptera over-wintering stage:the beginning period of wintering Lepidoptera (average daily temperature stability under19℃) on November30, the end of the winter average time (more than average daily temperature stability in11℃) for March11. Overwintering generation moth beginning see period on April1, on average, the earliest on March15, April15the latest.7. The first generation of Chilo suppressalis occurrence period and harm:between mid-may and early June, the larvae incubation period and high degree of rice tillering stage anastomosis. Moth to harm caused by the dry sheath on the late tillering to young ear differentiation phase1. First generation2the moth instar larvae in the late rice tillers, pupa in young ear differentiation.4. The first generation of the vided borer mouth there is a certain correlation between density and low heart rate, available regression equation y=0.2938In (x) to1.6902(R=0.9045)...