The Main Plant Diseases And Insect Pests Of Ningxia Corn Happen The Regular Pattern Reaching To Provide Prevention And Cure The Technical Research Against To Spread

The irrigated area wheat interplanting maize in Ningxia is 90,000 hectares, receive the influence that climatic conditions and variety upgrade, it is very serious that the plant diseases and insect pests of maize are endangered, especially maize leaf mite Tetranychus urticae Koch, the maize is big Leonard & Suggs, etc. of spot disease Exserohilum turcicum (Pass) exert a tremendous influence to losses of output of the maize. The thesis defends the peaceful plain and Yinchuan plain irrigated area in order to study the base with Ningxia, adopt and introduced, absorbed and already had advanced technology and cooperated with regional experimental study to combine together, have carried on test research to the rule of development of emergence of the maize and big spot disease, maize leaf mite, etc. and technology of preventing and curing, and the popularization launching the integrated control technology of the large area in step is demonstrated. Have made the following achievement:①Find out the rules of development of emergence of two spot leaf mites of maize and big spot disease , maize and relation with environmental factor, method to adopt life table work out maize two spot host, leaf of mite choose , nutrition effect and field spread the law of shifting.②Systematic surveys in field and laboratory were carried out to explore the dispersion pattern of two spotted spider mite, Tetranychus urticae Koch, and its selection of host plants in the irrigation region and the new reclamation region in Ningxia. The results showed that there are 88 species of host plants, including 59 species of wild plants and 29 species of cultivated plants. The plants good for the spider mite were found in the desert and semidesert areas of proreclamation. Nutritive function of 20 plant species to net productive rate (R0) of the spider mite was studied using the methods of life table. The result showed that the nutritive value of different host plants varies with different seasons. The dispersion pattern of two spotted spider mite among its host plants showed that some main wild weeds in farm land, such as, Capsella bursa pastoris, Calystegia hederacea, Cephalanoplos segetumji, Sonchus brachyotus and Plantago asiatica, and several cultivated crops, such as,Vicia faba, Glycine max and Zea mays, made up a host plant system, which was suitable for seasonal dispersion of the spider mite. Analysis indicates that one of the important reasons for the occurrence of the spider mite is the cultivation mode, that is, interplantimg maize with wheat or maize with soybeans. Fig 4, Tab 2, Ref 7.③ Go on 32 variety , 57 product maize variety disease resistance of time test relatively , screen the 7th , the 8th such as Dongdan, Central Plains form 32 grade 10 over is it able to bear heavy , small spot maize variety of disease to resist, go on by a large scale popularizing in every demonstration area.④ Is it carry on maize leaf mite take place according to temperature terms issue predict and carry on maize old spot disease take place degree in advance with prediction to prevent and cure period according to variety and climatic conditions to propose Examine and predict technology and method . On the basis of testing, have proposed the maize leaf mite, the prevention and cure indexes of the maize and big spot disease, especially by mite leading, dead leaf rate, danger index prevent and cure the putting forward of the index for the maize leaf mite of the basising, overcome forefathers is it prevent and cure what index cause hurt heavy is it investigate contradictory to unfavorable toing by mistake to regard worm's quantity once as.⑤ Screen the test after carrying on 15 each , chemical drug of time of 58 medicines, has put forward the security, a batch of new drug and integrated control technology and method of effective , economic prevention and cure maize and big spot disease , maize leaf mite ,etc.⑥ Propose preventing and curing the technology system in main plant diseases and insect pests of maize, popularize 2 totally in three years. 50,000ha2, demonstration area disease worm person who endanger in under 8%, than contrast district drop 78%. the increasing production rate is up to 12 equally. 85%, has made obvious economy, society, ecological benefits.