Cotton Science   2005£¬17(5)£º275-279

 

Effects of Controlled Release N Fertilizer on Photosynthesis Property
and Yield of Cotton

LI Ling-li1, MA Zong-bin1, TAN Jin-fang1, FANG Wei-ping2, XIE De-yi2, YANG Tie-gang2
(1.College of Agronomy£¬He¡änan Agricultural University£¬Zhengzhou 450002£¬China£»2.Cotton and Oil Crop Research Institute£¬He¡änan Academy of Agricultural Sciences£¬Zhengzhou 450002£¬China)ª¤ª¤

Abstract: Effects of controlled release N fertilizer that was applied by different quantity and methods vs. Urea £¨N 150 kg¡¤hm-2£©on photosynthesis property and yield of cotton had been studied in fields, so that the theoretical basis was provided for application and spread of controlled release N fertilizer expending in cotton production. The results showed that, the controlled release N treatment increased §¶PS¢òand Fv/Fo in cotton leaves at bolling and boll opening stage, and enhanced CAP, boll number plant-1 and boll weight. Compared with CK ,the seed cotton yield and fertilizer use efficiency of each treatment were as follow:(1) equal N (N 150 kg¡¤hm-2) used as base fertilizer increased seed cotton yield and N use efficiency by 10.3£¥ and 10.2 %,respectively; (2) equal N £¨N 150 kg¡¤hm-2£©used as base fertilizer and topdressing treatment(1¡Ã1) increased seed cotton yield and N use efficiency by 22.5£¥ and 22.4%, respectively; (3) N 120 kg¡¤hm-2 with 1¡Ã1 base fertilizer and topdressing increased seed cotton yield and N use efficiency by 12.3£¥and 40.3% , respectively; (4) N 120 kg¡¤hm-2 used as base fertilizer increased seed cotton yield and N use efficiency by 3.2£¥ and 29.0 %, respectively. In a word, cotton yield was increased in all the treatments of controlled release N fertilizer under this experimental conditions compared with CK, among which the highest yield was achieved by applying controlled release N fertilizer 150 kg¡¤hm-2 , half used as base fertilizer and half used as topdressing in early flowering stage.
Key words: cotton; controlled release N fertilizer; photosynthesis property; seed cotton yield; fertilizer use efficiency