Effects of different fertilizer application combined with different DPC quantities on photosynthesis property and yield of cotton directly seeded after wheat

Effects of three levels of N, P, K fertilizer application combined with two DPC spraying quantity on photosynthesis property and yield of cotton directly seeded after wheat were studied under a field condition. The results show that applying urea(225kg/hm²)，superphosphate(450kg/hm²),potassium chloride(150kg/hm²)and spraying DPC(90g/hm²)can improve the maximal PSⅡ light energy transformation efficiency (F_v/F_m)，PSⅡ activity(F_v/F_o),photosynthesis rate (Pn) and stomatal conductance (Gs) of leaves of cotton, and increase the canopy photosynthesis rate (CAP),bolls per plant, high-quality bolls and bolls weight of cotton. Compared with other treatments, lint yield is increased by 17.4%～33.9%.