湖北省棉花磷肥效应及推荐用量研究

Study on Response to Phosphorus Application and Optimal P Recommended Rate for Cotton in Hubei Province

通过14个大田试验,研究了湖北省棉花P肥效应及适宜用量。结果表明,适量施用P肥对棉花具有明显的增产增收效果,14个试验施P处理比对照处理增产子棉100～896kg/hm2,平均增产347kg/hm2;施P处理增产率2.1%～25.2%,平均增产率为10.4%;施P处理纯利润平均为1764元/hm2,产投比平均为6.61;P肥偏生产力和农学利用率平均分别为P2O551.27kg/kg和P2O54.15kg/kg。根据肥料效应方程,在当前生产条件下,棉花生产的P肥经济用量平均为P2O5112.7kg/hm2,推荐幅度为P2O542.9～183.2kg/hm2。土壤有效P含量与棉花P肥经济推荐用量呈极显著负相关(r﹦﹣0.7628**,n﹦13),根据土壤有效P含量(x,单位为mg/kg)水平,湖北省目前棉花生产适宜用P量(y,单位为kg/hm2)可通过公式y﹦273.42﹣78.488ln(x)求得。

A study was carried out in Hubei Province to evaluate the effects of phosphorus （P） fertilization rates on yield, economic benefit, P use efficiency and optimal P recommendation rate of cotton at 14 tested sites. The results revealed that the yield and profit of cotton significantly increased when P supplied moderately. The main results were as follows： （1）Compared with the treatment without P fertilizer, the cotton yield of P application increased to 100 - 896 kg/hm^2 for all treatments with an average increase of 347 kg/hm^2. The increment rate ranged from 2.1% to 25.2% with the average rate of 10.4% for P application. （2）The average net profit of the P application was 1764 Yuan/hm^2and the value to cost ratio was 6.61.（3）The average partial factor productivity of applied P （PFPP） and agronomic P use efficiency （APUE） were P3O5 51.27 kg/kg and P2O54.15 kg/kg respectively. （4）According to fertilizer response equations, the economical P application rate ranged from 42.9 kg/hm^2 to 183.2 kg/hm^2, and the average rate was 112.7 kg/hm^2. It showed that the economical P application rate had a significantly negative correlation with soil available P level, and the economical P application rate of cotton could be gained through the equation y ffi 273.42 - 78.488 In（x） （here y means applied rate of P2O5, x means soil available P content） in Hubei Province.