Studies On Succession Law And Divisions Of Maize Plant Diseases And Insect Pests Of The Major Corn Producing Areas In Anhui Province

Through the statistical analysis method, the paper studied the kinds and level of maizeplant disease and insect pests in Xiaoxian, Yingdong, Fengyang, Nanqiao, Feidong, Juchao,which were the the major corn producing areas in Anhui province. The law of evolutionwas studied, through the collating of materials for1911-2011.1.There were65kinds of maize plant diseases and insect pests in An hui Province.The diseases including17pasturage fungal diseases,2bacteria diseases and3viraldiseases, a total of22. And the pests including40insect,1mite,2mollusks, totally43.According to the period of pest damage,there are3diseases,17pests at seeding stage ofmaize;3diseases,6pests at the ear stage;10diseases,11pests at anthesis and kernelstage.2.The maize plant disease and insect pests that occurred in An hui Province weredivided into Huaibei Area, Anhui Eastern Area, the are along Huaihe River of Anhui, thearea around the Yangtze River in Anhui. The clustering results were highly consistent withthe geographic location of basic counties.3.When using clustering analysis method, choose the area of maize, the areaproportion of the total area of the main diseases and insect pests (small speck diseases ofmaize, the corn borer the underground pests), and of the total area of pest over the years asthe feature data. When the distance λ=4.5036, it can be divided into three categories. Onetype was from1991to1994, the second one was1995to2005,and the last one was2006to2011.And use that to stand for the occurrence and development of the main diseases andinsect pests over two decades. The diseases and pests had an aggravating tendency since1991. The first stage (1991-1994) was light, the proportion of the occurrence area wasbelow3%;The second stage was a period of smooth growth, the diseases reached theirpeak during2005and the pests in2002, the percentage respectively was10.01%and28.88%.And the third was a diseases rapid growth and diseases and insect pests seriousdamage stage, the percentage of the diseases was24.38%and reached their peak in2011and the pests was41.29%during2009.