Different Effects And Mechanisms Of Potassium On Varied Cotton Genotypes

Cotton is one of important cash-crops. There is great influence to cotton yields and fiber traits under K deficiency. However, K resources are very shortage in China. It is one of a way to resolve there problems to screen high K-efficiency (HKE) genotypes. 86 cotton cultivars had been collected from varied cotton inheritance lines, and studied the different physiological mechanisms of HKE and LKE (low K-efficiency) through different experiments. The main results were as follows:1. Solution culture was the first select method to screen varied cotton genotypes, by which the cotton genotypes had much difference under K-deficiency within a month.2. The suitable K concentration for cotton growth was 20 mg/L at seeding stage selection: and the critical K concentration for K efficiency determining was 1.0 mg/L.3. Fractionated, stepped selection and Identification, one HKE cotton genotype 103 and one LKE cotton genotype 122 had been got.4. Primary study had been done on physiology mechanism of varied cotton genotypes at seeding stage, and results as follows:4. 1 K-deficiency symptoms appeared after sowing a week among different cottongenotypes, but HKE cotton symptoms were weak.4. 2 K accumulations of LKE cotton was sensitive to different K level, but HKE cottonwas not at the same K levle4.3 Shoot / root ratio of HKE cotton genotype was big, and the ability of absorption andtransportation K was higher for HKE than that of LKE cotton genotype.4. 5 Chlorophyll of up leaves was higher than down leaves at -K treatment for HKEcotton, but that of the LKE cotton was the antithesis.4. 6 The activities of SOD and POD increased at -K treatment, but the increased rang of activities of POD were smaller than SOD, and HKE cotton genotype SOD activities were higher than LKE cotton genotype.5. Cotton yield and fiber traits of different cotton genotypes and their different mechanism had been studied, and results as follows:5.1 The root of 103 developed better than 122, its root areas were big, and the root had more root hairs.5.2 103 grew much better than 122, the yield of 103 was 2.57 times and 1.83 times of 122 at -K and +K treatment5.3 K content of different organs of 103 was lower than that 122, which showed that 103 could sustain its normal physical function with low K content.5.4 there were more nutrtion matter distributed to propagation organ for 103, and the rate of K economic utilization of 103 was about 2 times to 122.5.5 The result showed that K fertilizer could make much better for fiber traits, potassium could increase fiber Length, Uniformity,Strength and Micronaire, but Fiber elongation...