麦棉套作系统生理学特性研究

在大田条件下利用同位素示踪技术对麦棉套作系统的生理学特性进行了研究。结果表明，麦棉套作系统的生长发育表现出两头强（小麦抽穗前长势强，棉花吐絮期贪青晚熟），中间弱（共生期内小麦早衰、棉苗长势弱）的特点；小麦生育后期（抽穗后）特别是在灌浆后期群体根系活力明显降低，穗内３２Ｐ矿质分配比率减少，茎叶的代谢活力下降；套作棉花在蕾铃期群体根系活力降低，且根系活力高值期出现的时间后延１５～２５天，高值持续期明显缩短。生殖器官内３２Ｐ矿质分配比率，从蕾期一直到吐絮期也不同程度的相对降低。但麦棉套作经济效益比单作棉花增加１７８％以上，本文根据研究结果提出了栽培技术建议。

Study on the Physiological Characters of Wheat_Cotton Interplanting System

The physiological characters of wheat_cotton interplanting system were studied in the field by radiotracer.The results showed that the growth vigour of wheat_cotton interplanting system became stronger before head sprouting of wheat and during boll_opening stage of cotton,while during the symbiosis period it became weaker than that of CK.The population root activity, 32 P mineral distribution percentage of spike and metabolic activity of stem and leaf of interplanting wheat decreased significantly than that of CK.The population root activity of interplanting cotton decreased significantly at the square and boll stage,with the high value period delayed 15 to 25 days.The 32 P mineral distribution percentage in reproducing organ decreased from square to open boll stage as well.Economic benefits of wheat_cotton interplanting system increased over 17 8 percent than that of monoplanting cotton.