河西内陆灌区不同灌水施氮水平对棉花产量构成的影响

Effect of different water and nitrogen supply on yield and its components of cotton in inland irrigation district of Hexi in Gansu

研究了河西内陆灌区不同灌水量和氮肥施用量对棉花产量构成因素及产量的影响;设置了3个灌水水平和5个氮肥水平,供试棉花品种为陇棉2号。结果表明,灌水量和氮素都会影响棉花的单株结铃数、单铃重和衣分,最终影响棉花的产量。其中灌水量主要影响棉花的单株结铃数和产量,随着灌水量的增加,棉花的单株结铃数相应增多,但棉花的生育期相对延长,因而降低棉花的霜前花率。氮肥对棉花的单株结铃数、单铃重、衣分和产量影响都很大,与对照不施氮肥(N0)相比,试验各处理施用氮肥后,棉花的单株结铃数、单铃重、衣分和产量差异达到极显著水平。要使氮肥发挥最好的肥效,必须严格控制灌水量,在本试验土壤全氮0.71 mg/kg、速效氮含量为61.37 mg/kg的沙壤土条件下,灌水总量控制在3 000 m3/hm2,氮素施用量为350.0 kg/hm2时,可以使棉花的产量达到最高。

In order to detemine the impact of irrigation and nitrogen supply on yield and its components of cotton, 3 treatments of irrigation and 5 treatments of nitrogen supply levels were used. The test variety is Longmian No. 2. The re- sults showed that irrigation and nitrogen supply affected the boll number per plant, boll weight and lint percentage, and ultimately the yield of cotton. Irrigation mainly affected the boll number per plant of cotton. With the increase of irrigation, the number of bolls increased correspondingly, but the period of fertility extended, thereby reducing the flowering rate before frost. Nitrogen supply mainly affected the number of bolls per plant, boll weight and lint percentage of cotton plant. Of all treatments, the application of nitrogen and no nitrogen, the yield difference reached a very significant level. However, to play the best nitrogen supply efficiency, we must strictly control irrigation. In the conditions of 61.37 mg/kg N content in the soil and normal application of P, K fertilizer,an irrigation rate of 3 600 m3/hm2 and a N application rate of 350.0 kg/hm2 could make the highest yield of cotton.