Study On Effect Of Using Strategy Of N Fertilizer On Growth Strategy Physiological Characteristic And Yield Component Of Land Cotton

The experiment in dafeng town of hutubu county, take the single factor area of experimental design, in2009-2010different level of nitrogen in cotton field experiment; In2011, on the basis of the optimum litrogen fertilizer for total in different period of the field experiment. The main experiment results are as follows:1. In the whole process of cotton fertility, the processing of cotton plant height, leaf number, main;tem really branch number and individual the boll number with nitrogen and presents the different "S" type rend, each branch between treatment beginning section of the difference was not significant.Different years were different treatment dry matter accumulation of dynamic change regulation can be used "S" curve equation fitting, and dry matter accumulation rate changes are in the single-peak curve, spikes in about105d or so after seedling; Among them, the medium of fertilizer N3processing, the total dry matter of cotton leaves, stems, and dry matter to the dry matter at the fastest growth period ahead, key period for long period, dry matter accumulation and accumulation rate increase.2. In the whole process of cotton family, each processing plant nutrient absorption rule are performing at seedling stage accumulation for less, bud period is increasing rapidly, flowering slow, the bell reached a peak period, bolls and reduced the development trend. One of cotton nitrogen, phosphorus and potassium were focused on keeping the absorption of the seeding24-108d,22-98d,14-54d between. The treatment,300kg·hm-2,450kg·hm-2nitrogen treatment of accumulated nitrogen of higher, nutrient keeping early, continues for a long time.3. Increased nitrogen application significantly increased the number and heavy weight principal, in2009and2010, the fertilizer treatments and the single boll Numbers are not than average nitrogen treatment increased0.80and0.73the bell; Principal grew by an average of0.36g weight and0.43g, and two years of lint yields1514.95kg·hm-2and1785.88kg·hm-2, are better than the same year not fertilizer treatments increased by16.23%and52.20%respectively, high rate than deal with increased by6.46%and19.33%respectively. Based on nitrogen fertilizer and cotton output of the relationship between a yuan quadratic equations, drawn332.4kg·hm-2, and obtain the highest seed cotton yield can reach5210kg·hm-2; According to2010market price calculation, economic best nitrogen is290.1kg·hm-2, econom best seed cotton yield of5200.5kg·hm-2.Medium N can significantly improve quality cotton, a major increase cotton fiber length uniformity, strength and elongation at break, but to micronaire and maturity index a little effect.4. Topdressing nitrogen period is different, the function of cotton leaf SPAD value, net photosynthetic rate and leaf area index have influence. Among them, the basal fertilizers and spend the bell of nitrogen topdressing period N3treatment improved the function of the blade SPAD value and net photosynthetic rate. At the same time as the passage of growth period different treatment function of cotton leaf and soluble protein content of soluble sugar on the same change trend, are first increases, then reduce, early in the flowering reaches maximum and minimum bolls, but the period of the fertilizer to has no significant effect on content.5. Topdressing nitrogen period is different, of cotton fall off at rate; three peach proportion and production have been affected. Among them, the basal fertilizers and spend the bell of nitrogen topdressing period N3processing significantly reduce the loss rate at, at the rate of N2, fall off, respectively, compared with the48.98%and44.44%lower N4interchange processing, significantly increase the yield per plant and the boll number and principal heavy, and respectively than N1, N2and N4interchange processing were increased by25.58%,7.40%,13.10%and5.73%,3.74%and1.76%, than N1N2and N4lint and improve the interchange processing respectively29.61%,14.30%and11.63%; Budding period and flowers; the period of nitrogen topdressing N4interchange processing production after N3processing.