| This paper briefly analyzed pests control in Shanghai in which plant structure was becoming complicated and diversified such as increasing planted area of economic crops and special crops in new agricultural structure adjustment.So command forecast and prevention of pests were needed under the high demand of high quality,high production,free pollution, also decrease dosage of chemical pesticides,to make economic threshold suitable to agricultural production,and make sure urban agriculture safely produced and developed high-quality agricultural and sideline products.Pests control in Nanhui district was introduced too.Although rice pests control had formatted relatively perfect integrated control system,pests of economic crops aggravated and their occurrence regular had some changes as rice stem borers that inferior pests became major pests and new pest species occurred.At this basis,it was demonstrated that nowadays pests control could basically satisfy needed of present production,but facing new situations and conditions,agricultural plant protectors must keep up with need of development,adjust direction continually,learn new knowledge and strengthen new technique extension to insure steady development of agricultural production.The example of the study on integrated control technology and extension of rice stem borers showed the content of pests control and extension on the level of county in detail. Stem borers are important rice pests as called "southern stem borers and northern grasshoppers" historically.With change of rice farming system and culture way,The occurring extent of three species of stem borers Tryporyza incertulas,Chilo suppressalis and Sesamia inferens have changed a lot since 1950 to 2000.For example,stem borers broke out and caused great loss to peasants in Zhuqiao,Donghai,Laogang of Nanhui District.About stem borers control,according to IPM principles,making command of biology and occurrence disciplinarian of stem borers especial T.incertulas and C.suppressalis,use resistant variety,choose appropriate control through agricultural measures such as sowing and growing period and use appropriate pesticides,assort chemical control with biological control,decrease or avoid pesticides killing effect on natural enemies,bring their effect of control pest into play.In addition,use simple and convenient methods such as phenology and effective accumulated temperature together with investigation for overwintering cardinal number and instant collection of trap-lamps material for mid-term early and predication and forecasts,which can better keep loss of stem borers under economic threshold and get ideal economic income.Experimens results were summarized as follows:1.At the optimum temperature of 27℃,the survival rates of a generation of C. suppressalis,population increase indexes,net reproductive rates,innate increase capacity were 13.24%,9.65,7.687%and 0.049 respectively.At 30℃,these indexes were 15.3%, 15.11,16.076%and 0.068 respectively.The average life spans at two temperatures were 42.06 days and 40.97 days respectively,which showed that population grew by 10 to 15 times by 42 days or so.2.Occurrence and damage degree of T.incertulas first,second and third generations were influenced by rice sowing and growing period.Light harm degree of stem borers and little influence were caused if sowing and growing period was remitted to around May 23.In addition,it was demonstrated that insect source could decreased 81%if rice was sowed around May 23 by analyzing the relation between T.incertulas first and third generation strap-lamp and sowing and growing period.3.As conventional spray method,pesticides such as 40%Daokang EC(80 mL per mu), 20%triazophos EC(150 mL per mu ) and 40%Xinke EC(80 mL per mu) mixed with 60 kg water were used first time in the dominant hatching period of T.incertulas and second time after 7 to 9days,which could control T.incertulas in the ear stage.4.The spider communities of middle rice in Nanhui district was consisted of 22 species of 9 families.Erigonidum graminicolum,Ummeliata insecticeps,Pirata subpiraticus and Dyschiriognatha quadrimaculata were dominant species,which appeared number peak in the mid august and mid or last September.Among 7 insecticides,Minglinte,Shanrui,Sijile and regent had better control effect against T.incertulas and had less influence on spider communities,number and diverty.5.Numbers of T.incertulas overwintering generation related to rainfall in april and may closely.For example,the overwintering mortality in spring was over 90%because of large rainfall in April and May,2002.The main natural factors,which caused explosion of third generation T.incertulas were high temperature and drought,which were key factors of prediction and forecasts for overwintering generation moths.
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