Study On Growth And Development Of Wheat-cotton Inttercroping In Xinjiang

The research on the wheat-cotton intercropping in Xinjiang province has conduct from many levels and angles , concerned cultivation,meteorology,plant nutrition . For affording theoretical support on the technical development of wheat-cotton intercropping of Xinjiang, these is the all-round first research on the wheat-cotton intercropping in the cotton area of north-west. The studies is on the biological characteristics and physiological characteristics of wheat-cotton intercropping system , on the effect of major ecological factors, on the nutrients uptake to allotment regulation. The contents are followed below:(1)The study on the growth and development on the wheat-cotton intercropping of Xinjiang province indicated that: the open boll stage in the wheat-cotton intercropping is later than monoculture cotton, and growing period is longer 4 days than monoculture cotton because the symbiosis period has 50 days. And the agronomic character such as high and cough are little than monoculture; but the growth rate is higher in the wheat-cotton intercropping than monoculture cotton after symbiosis period. At last, the width and stem thickness et. are surpasses finally the single plant cotton. The peak of leaf area index is 2.77 in wheat-cotton intercropping on the July 25th. From the ratio chlorophyll a/b of stem leaves, it's about 3.0 and little on the period stage and on the last stage. The output of ginned cotton in intercropping cotton is 1338.4 kg/hm2. .It's about 65% in the single planting. To the yield and components of yield, the fiber traits are not significant differences on fiber length, fiber strength and Mic. value.(2)The study on effect of the field environment in cotton-wheat intercropping plantation models in Xinjing indicated that it had a different level's reduction to light intensity, soil temperatures, and wind speed in cotton-wheat intercropping plantation models than that in monoculture cotton plantation models. Comparison with monoculture plantation model, the PAR is decrease 6.1%, the soil temperature decreased 2.9% and the wind speed decreased 0.3% in the cotton-wheat intercropping cotton field .the soil moisture content is more higher on the border row than that on the middle row both in the monoculture field and in intercropping field., and the natural moisture content more bigger along with more depth. There was little difference on the depth 20cm; the moisture content on the border is curve with one peak and the biggest is 10~15cm depth, and the moisture content of dry soil has not significant difference.(3)The results of study on wheat-cotton intercropping system for nutrients uptake to allotment regulation of crops in this article indicate that: During symbiotic time, the total uptake of nutrients in cotton intercropping are less than the total for cotton alone. After wheat harvest , the rate of nitrogen,calcium uptake of cotton intercropping have obviously faster than cotton alone ,the total nitrogen,kalium uptake have more than cotton alone ,and only for the total uptake of phosphorus essentially the same as cotton alone, but the peak of nutrients uptake in cotton intercropping is later than cotton alone. With reproductive process, the nutrients concentration of the organ in both cotton intercropping and cotton alone gradually decline. The ratio of N,P,K in leaves gradually reduced ,while the proportion of bud bell gradually rise, the proportion of nitrogen assigned to nutrients organ in cotton intercropping is higher than cotton alone ,the proportion of those assigned to reproductive organ is lower than cotton alone, the allotment regulation of P,K is opposite to nitrogen.