关键词:
机采棉, 磷肥效率, 养分吸收, 干物质积累

Abstract: This paper studied the effects of different phosphates fertilizer application rates on nutrient uptake and phosphorus use efficiency of cotton under machine harvest mode (10 cm + 66 cm + 10 cm + 66 cm + 10 cm) in Xinjiang, so as to provide theoretical basis for rational operation of phosphate fertilizer in cotton harvested by machine. Taking ‘Xinluzao 57’ as research object, the paper studied the 5 different P fertilizer (P2O5) treatments (0, 75 kg/hm2, 150 kg/hm2, 300 kg/hm2, 450 kg/hm2) on dry matter accumulation and N, P, K absorption of each growing period, P use efficiency and yield. The results indicated that  moderately increasing P fertilizer was favorable for dry matter accumulation, yield and N, P, K accumulation increase. All these items reached the highest level especially under 75~150 kg/hm2 treatment. The dry matter accumulation, yield and N, P, K accumulation of various organ were 9.85%, 24.2%, 6.24%, 27.1% and 51.6% higher than those of the control, respectively. Under 75 kg/hm2 treatment, the phosphorus use efficiency, agronomic efficiency, and partial productivity were reduced along with the increase of P application rate. All these items were the highest under 75 kg/hm2 treatment as 2.4%, 13.50 kg/hm2 and 67.39 kg/hm2, respectively. Rational P application promoted the yield increase of mechanical harvest cotton, and under 75 kg/hm2 and 150 kg/hm2 treatments, the yield increased 25.05% and 38.53%, respectively, significantly higher than that of the control. Thus, the application of P2O5 for 75~150 kg/hm2 was the optimal under the conditions of this experiment.

Key words: machine picking cotton, P fertilizer efficiency, nutrient uptake, dry matter accumulation