Studies On Regularity Of Rice Two-speciifc Migration Pests In Donghai County Of Jiangsu Province

Cnaphalocrocis medinalis, BPH and WBPH is bigger harm two migratory pests in rice production.In recent years, serious occurrence frequency increased significantly, more and more serious harm, aserious threat to the grain yield and food safety of rice, rice diseases and insect pests in China hasbecome a difficult problem in prevention and control of. This paper studies the two move rule pests inDonghai County area, causes and prevention measures, the results are as follows:(1) Cnaphalocrocis medinalis migration time, peak time is moved, the harm heavy, difficult tocontrol leaf, in2010for the first time as early as July3rd rolls, rice, in2006rice leafroller beginningoccurrence stage of late, as of August2nd, the two year difference30days, generally in earlier yearshazards are heavier, main pests in rice field generation and consistent. Five (three) generation ofCnaphalocrocis medinalis damage investigation shows, the biggest harm process in2003, average mucatches peak period to3419.1head, there are records of the most serious one. Six (four) generation ofCnaphalocrocis Medinalis and five (three) generation compared to more serious hazards. For ten yearsthe six (four) generation of Cnaphalocrocis medinalis average mu catches the peak period for an averageof2177.6head, which in2003most serious outbreak, the daily average mu catches peak of5948, is arare since records,2005,2007,2008,2010more serious hazards, average mu catches peak to achieve2500above, this six years (four) generation of immigration peak times more, moved to larger dropvolume, peak period too long, ovum is high,2004,2006,2009,2011of low stress harm, average mucatches peak period to500above.(2) the occurrence characteristics of rice planthopper is moved into the early, peak time, difficult tocontrol.2002to2012Donghai County brown planthopper beginning period fluctuations, the overalltrend of the beginning of period was delayed, from the earliest in2002June17th, the latest in2011August13th, the two year is57days. Donghai County white backed planthopper was seen in the periodof2003to2012ten years (Figure3), basically appear in late June and early July, the beginning ofperiod is relatively stable, only the2011special appear in late July.2003-2012brown planthopperoccurrence is occurrence state in the years of2006and2007, in Donghai County appears to be movedinto the period of early, immigration peak time, moved down the amount is large, the occurrence,severity to Donghai County’s history, several other annual occurrence of lighter. The white backedplanthopper occurrence amount is moderate, the characteristics of the basic medium, local outbreak. In2011, the county of light, four (1), five (2) were light incidence degree is in recent years the most lightyear. The white backed planthopper occurrence in the earlier stage of the overall quantity, small tomedium.(3) rice "two moved" pest outbreak causes mainly include the climatic conditions are suitable, alieninsect source, migration, peak time, control methods, planting more improper several waydiversification etc..(4) there are three main types of Donghai County two migratory pests prevention measures: agricultural control, chemical control, biological control.