Effects of controlled loss fertilizer on cotton leaf senescence, yield and fiber quality.

A two-year(2010-2011) field experiment was conducted to study the effects of cotton-special controlled loss fertilizer(CLF) on cotton leaf senescence,yield and fiber quality,using conventional cotton variety Guoxinmian3 and hybrid cotton variety Guoxinmian8 as materials.Compared with the control(applying nitrogen and potassium fertilizers while sowing and top-dressed at full-flowering stage,and applying phosphate fertilizer equivalent while sowing),CLF could utilize the molecular interactions between lose control agent and fertilizers,trap and reduce the loss of fertilizer significantly,increase leaf potassium(K) content by16.7% ～ 37.7% during boll-filling and early boll-opening period therefore raise the net photosynthetic rate and leaf soluble protein content,enhance the activities of SOD and CAT,as well as reduce the reactive oxygen and MDA contents.The yellow leaves rate of Guoxinmian8 at the late boll-opening stage was obviously decreased by 33.7%,thus its fiber length and strength was improved.However,CLF did not impact total seed cotton yield of both varieties.CLF had no obvious influence on leaf senescence of Guoxinmian3.Considering its just one time application,CLF could be a simplified fertilization in Huang-Huai-Hai cotton production region.