Simulation of cotton dry matter accumulation and distribution and nutrient absorption in apricot-cotton intercropping system

With the aim of providing a theoretical basis for high efficiency fertilization of cotton in the fruit-cotton intercropping system, the influences of apricot-cotton intercropping cultivation models on the dry matter and nutrient accumulation of cotton were studied under natural ecological conditions in South Xinjiang. The dry matter and nutrient accumulation were fitted by using the Logistic equation. The results show that the fastest accumulation rate of total dry matter of the intercropped cotton is from 73 to 99 days after the emergence, and the rapid growth period of total dry matter accumulation is from 35 to 59 days. The maximum average accumulation rate is about 278.79 kg/d. The fastest accumulation rates of N, P2O5 and K2O nutrients are 56 to 59d, 48 to 62d and 48 to 52d after the emergence, the rapid accumulation periods are 3638, 2932and 3958d, respectively, and the average accumulation rates of largest absorption intensity are 3.51 kg/d, 1.47 kg/d and 2.64 kg/d. The intercropped cotton transports part of the photosynthetic products and nutrients to stems and leaves, and then reduces the distribution to the buds and bolls, thus affecting the improvement of yield and quality.