Study On The Causes Of Cotton Senilism And The Measure To Prevent Or Resist It In Alluvial Flat And Polder In Tongling

Cotton is a full important economic crop, but cotton premature senility is one ofproblem mainly to affect cotton yield and quality in Tongling, Anhui province. The purportof the paper is to discuss the cause of cotton premature senility and the measures areadopted for prevention and impedance it in entironment area alluvion flat and polder inTongling.The paper researchful conclusion to educe is that foundation on a pre-worthy personstudy fruit about it's concept, type, symptomatic represent, cause of cotton senilism anddifference with cotton prematurity where it was appeared on books and journal at present,after have did a mass of experimentation and investigation, make analysis prudent.The text consider that say about weather factor, abnormal climate, specialties isdroughty duration, is factor chiefly work Tongling's cotton senilism, next factor istemperature, rainfall not work effect of cotton senilism; say about environal pollution,cotton senilism acreage after it suffer injury related osculating to 2 index which highestvalue of consistency and exceed mark rate of soot daily equal value, but unrelation with letquantity of soot and powder dust.soil PH, cotton senilism acreage and reduction of outputquantity related osculating to acid rain frequency on alluvion flat area. say about soil,cotton senilism degree on sandy soil＞clunch＞soil, farming nature of Ash Sand Clay onalluvion flat area and Ash Sand Mud Farmland of Disentangle Latent Water on polder areaare stabile relativly, it is small to suffer effect of weather in different year; cotton senilismdegree are influenced for two factor which soil organic matter and soil PH; if siol droughtwill work cotton to languish during sensitive time of cotton require water, prematuresenility is severe in cotton bearing evening.say about plant diseases and insect pests, cottonsenilism acreage doesnot relation with take place acreage of plant diseases of necessity,cotton fields arises cotton Blight are not result in senilism of necessity, whereas insect peststhat bring on senilism, Tetranychus spp.and Aphis gossipii are severest, Lygus spp.,Helicoverpa armigera.Hǖbner, Helix graminum are lightest.say about planting mode, cotton is easy to arises senilism that intercrop or interplanting with corn, watermelon, potato,capsicum etc. crop, especially adopt the manner of growing in mantled farmland withmembrane.say about field care, trasplant is senilism severe compare with direct seeding; itis light with deep plough up compare with shallow; senilism that fertilize deep or socket islight compare with pour liquid fertilizer on cotton in alluvion fiat area, but it is not patentabout representation senilism one another in polder area; senilism to adopt balancefertilization with N15.5—P0—K13(in alluvion fiat area) and N11—P3.5—K16(in polder)are light compare with traditional; senilism is severe that cultivate after vigorous bloomperiod compare with do not; it is not patent to train to senilism representation.The text consider outside factor which weather, specialties is droughty duration,planting mode and field care measures etc.all should lead cotton senilism. But itsinfluencing manner and active degree are different to cotton senilism, it is complexmultiplicity, almost involve producing tache every, and under dynamic changing.