| Cotton,as one of the most important economic crops in China,has been widely sown in recent decades.Xinjiang’s cotton planting area has reached 80 percent of the country’s total output has reached 87 percent.However,with the continuous sowing of cotton for many years,the phenomenon of "three insects and two diseases" of cotton is gradually prominent.It has become a serious problem in agricultural production practice that continuous cropping obstacles caused by allelochemicals lead to deterioration of soil properties,poor crop growth,disease occurrence and limited yield growth potential per unit area.The other sense and self sense under the category of allelopathy also have the above problems.In this study,allelopathy and continuous cropping disorders of Cotton in Xinjiang were comprehensively described and analyzed,and the main manifestations of continuous cropping disorders,main sources of allelopathy substances and release pathways were summarized.Cotton tissue is studied through indoor germination test,leaching solution of solanaceae,farmland weed striga cucurbitaceae crops in xinjiang melon broomrape of allelopathy,in order to use cotton and solanaceae,cucurbitaceae,crop rotation,so as to use cotton both sense(feeling)his advantage,the decrease of cotton continuous cropping and melon broomrape host crops,and to control weeds melon broomrape multiple role.The effects of different subduction measures on cotton yield formation and allelopathy were studied by field plot experiment,and a comprehensive evaluation method of allelopathy self-toxicity in cotton field was put forward.Main research results:(1)Cotton seedling tissue extract has a certain allelopathic inhibition effect on melon seed germination.According to this premise,the effects of different genotypes of cotton seedling extract on seed germination rate at different concentrations were studied.Effects of cotton seedlings of the same genotype on seed germination rate at different concentrations.(2)For xinjiang decades of unchanged cultivation model,resulting in a variety of prominent problems.The effects of different reduction measures on improving continuous cropping obstacles and reducing allelopathic self-toxicity of cotton were studied.In order to find a better reduction measures to change soil microbial flora and control the effects of cotton field nutrient utilization.(3)by alkaline hydrolysis nitrogen,available phosphorus and available potassium in 0 ～20 CM soil layer,the CRI(cotton | rape intercropping),RIM(intercropping + microbial fertilizer)and CC(cotton continuous cropping)and CM(continuous cropping cotton +microbial fertilizer)under different continuous cropping patterns are analyzed.The net changes of alkali-hydrolyzable nitrogen were negatively correlated with cotton seed cotton yield,while the net changes of available phosphorus and available potassium were negatively correlated with cotton seed cotton yield.(4)The allelopathic effects of soil extracts on cotton seeds were tested by different treatments of root zone soil extracts in cotton field,and whether the allelopathic self-toxicity of cotton field could be effectively reduced was studied.In order to get the best treatment method of soil extract in cotton root region to reduce allelogenous self-toxicity. |
