| The cotton was tested through field plot experiments at the Water-saving Irrigation Station of Xinjiang Academy of Agricultural and Reclamation Science in 2014. A total of fifteen treatments was set, that three water levels(W160%ETc, W280%ETc, W3100%ETc, where ETc was the crop evapotranspiration.) and five fertilizer levels(N, P2O5, K2O)(F0.6:150、60、30;F0.8:200、80、40;F1.0:250、100、50;F1.2:300、120、60;F1.4:350、140、70). Effect of water and fertilizer coupling on cotton growth, yield, water use efficiency and soil moisture change rule, soil NO3-Ntransport rule and nutrient absorption under the condition of drip fertilization was studied. The main conclusions were made as following:(1) Irrigation water had significant effect on the plant height, branch number and effective number of fluid, the fluid quality and seed cotton yield, and it had a significant effect the stem diameter and leaf area index. They were increases with the increase of irrigation water. Fertilization had significant effect on plant height, stem diameter, branch number, leaf area index, effective number of fluid, fluid quality and seed cotton yield. The effect of the coupling of water and fertilization on effective number of fluid, fluid quality and seed cotton yield reached an extremely significant leve. The cotton, whose Irrigation water was 60% ETc, suffered the severe water stress. The indicators had a trend of increases first and then reduce with the increase of fertilizer rate presents and reach maximum at the fertilization treatment of F1.2 under the same water level. Showing a phenomenon that F1.2 > F1.4 > F1.0 > F0.8 > F0.6. The phenomenon showed that high fertilization had certain inhibitory effect on crop growth. Seed cotton yield had a quadratic parabola relationship with aboveground dry matter and water use efficiency. Aboveground dry matter also had a quadratic parabola relationship with water use efficiency. With the increase of water efficiency, yield and aboveground dry matter increase first then reduce. To seek the optimal relationship between them needs to be studied further.(2) The conventional water 100% ETc and conventional fertilization 250-100-50 kg/hm2(N, P2O5, K2O) can obtain higher seed cotton yield, effective number of fluid above 11.5 / plant and water use efficiency was 1.50 kg/m3; But the treament’s water use efficiency can reach 1.57 kg/m3,which irrigation water was 100% ETc, fertilizer rate was 300-120-60 kg/hm2(N, P2O5, K2O).And compared with conventional fertilization 250-100-50 kg/hm2(N, P2O5, K2O), its seed cotton yield can be increased by 5.7%, though more than 50-20-10 kg/hm2(N, P2O5, K2O) fertilizer were used with drip fertigation, under the film in ShiHezi of XinJiang(3) 100 kg lint per production, N P K nutrient uptake averaged N 11.27 kg, 2.78 kg P2O5 and K2 O 13.3 kg. Fertilization could significantly increase the N P K accumulation amount of cotton plant. The N P K accumulation amount increased with the fertilizer rate increases, but after the 300 kg/hm2, the change of N accumulation amount was not obvious. Irrigation has significant effect on plant N P K accumulation amount, show that W3 > W2 > W1. Because this testbed soil k content was higher, the K affected K accumulation amount wass limited, the K accumulation amount of cotton plant difference is mainly due to differences in the quality of dry matter. Along with the advancement of growth period, leaf aging off gradually, the bolls start open, leaf nutrient absorption proportion gradually reduce, bolls gradually increase. Under the different water levels, the highest fertilizer use efficiency could be obtained by low fat, but its production was serious, it does not conform to the requirements of the production. Above average level of fertilizer use was more advantageous to both yield and fertilizer use efficiency. Irrigation water 60% ETc, fertilizer rate 300-120-60 kg/hm2(N, P2O5, K2O) can obtain the highest N P K utilization efficiency, and the irrigation water 100% ETc, fertilizer rate 150-60-30 kg/hm2(N, P2O5, K2O) treatment’s N P K recovery rate was the highest.(4) NO3- N mainly vertical distribution in the 0 to 40 cm soil layer and gradually reduce with the deepness of soil deepen. Beside it mainly concentrated in less than 15 cm in horizontal direction and downward migration with the increase of irrigation water. In a horizontal distance hole 0 cm, in the vertical depth more than 60 cm, there was no significant difference between soil moisture content of W1 and W2, but they significantly lower than the W3. The cotton main root in vertical depth 60 cm, the moisture content of W3 were mainly distributed in vertical depth 50 cm- 80 cm, so in this range was better for cotton root system to absorb moisture and fertilizer, thus further to improve the production. In a horizontal distance hole 15 cm, 30 cm, the soil moisture of W1, W2 and W3 was mainly distributed in the vertical depth more than 60 cm. |
PDF Full Text Request