Studies On The Effects Of The Cultural Factors On The Fiber Quality Of Different Fruiting Position In Cotton

By using non-Linear regression orthogonal combination design ( the optimum mix design), the effects of cultural factors on fiber quality were analyzed; the space and time distribution regulation of fiber quality was analyzed on fruiting positions. The best model to acquire the superior quality and high yield under the condition of special ecosystem and cultivation in Hunan was discussed. Main results were as follows; 1 The regression model between cultivation factors and fiber quality was established. The regression model between fiber quality (Y), sowing date (Xi), planting density (Xz), N application rate (Xs) was as below: Y=3. 9295+0. 21708X1+0. 056394X2-0. 3954X,-0. 20319XVO. 27002X22-K). 212949X2,-0. 27276Xi X2-0. 1787 X, X3-0. 0508 X2X3, simulation precision was higher, the value of x2=0. 421217, no significant difference and the equation was effective. Through calculation, The model that highest fiber quality can be obtained is sowing at April 23th, 1600 plants/667, m2, dressing N 22kg/667mi . N application rate is one of significant cultural factors that affects the fiber length and strength; Sowing time is a significant cultural factor that affects the micronaire; The density is a significant cultural factors that affects elongation rate.2 By clustering analysis , the 65 fruiting position of cotton plant can be divided into 6 types, and the fruiting position of II梀type possesses higher fiber quality, but I type VI type is the worst, and IV is the best type which located on the middle part fruiting branches. 3 The contribution of bolls on 2nd sympodial node to the fiber quality is biggest, contribution rate reached to 38. 31%; as for 1st sympodial node , 31.81%; and 3rd sympodial node , 29. 88%04 The research showed that the fiber quality of pre-summer bolls is the worst, its contribution rate to fiber quality was 16.38%, the fiber quality of summer bolls is best, its contribution rate to fiberquality was 35.36%, the fiber quality of early autumn bolls of contribution rate was 28. 54%, the fiber quality of late autumn bolls of contribution rate was 19. 72%.5 The results showed that the environment and cultivation had biggest effects on micronaire, but no significant effect on the fiber length and uniformation.