Response of the enzymes to nitrogen applications in cotton fiber (Gossypium hirsutum L.) and their relationships with fiber strength  

作　　者：WANG YouHua1, FENG Ying1, XU NaiYin1,2, CHEN BingLin1, MA RongHui1 & ZHOU ZhiGuo1 1 Key Laboratory of Crop Growth Regulation of the Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China 2 Institute of Industrial Crops, Jiangsu Academy of Agricultural Science, Nanjing 210014, China 

出　　处：《Science China(Life Sciences)》2009年第11期1065-1072,共8页中国科学（生命科学英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos 30771277 and 30771279);Research Fund for the Doctoral Program of Higher Edu-cation of China (Grant No 20060400944);the State Key Laboratory Fund (Grant No PPB08011)

摘　　要：To investigate the response of key enzymes to nitrogen (N) rates in cotton fiber and its relationship with fiber strength, experiments were conducted in 2005 and 2006 with cotton cultivars in Nanjing. Three N rates 0, 240 and 480 kgN/hm2, signifying optimum and excessive nitrogen application levels were applied.The activities and the gene expressions of the key enzymes were affected by N, and the characteristics of cellulose accumulation and fiber strength changed as the N rate varied. Beta-1,3-glucanase activity in cotton fiber declined from 9 DPA till boll opening, and the beta-1, 3-glucanase coding gene expression also followed a unimodal curve in 12—24 DPA. In 240 kgN/hm2 condition, the characteristics of enzyme activity and gene expression manner for sucrose synthase and beta-1,3-glucanase in developing cotton fiber were more favorable for forming a longer and more steady cellulose accumulation process, and for high strength fiber development.To investigate the response of key enzymes to nitrogen (N) rates in cotton fiber and its relationship with fiber strength, experiments were conducted in 2005 and 2006 with cotton cultivars in Nanjing. Three N rates 0, 240 and 480 kgN/hm2, signifying optimum and excessive nitrogen application levels were applied.The activities and the gene expressions of the key enzymes were affected by N, and the characteristics of cellulose accumulation and fiber strength changed as the N rate varied. Beta-1,3-glucanase activity in cotton fiber declined from 9 DPA till boll opening, and the beta-1, 3-glucanase coding gene expression also followed a unimodal curve in 12—24 DPA. In 240 kgN/hm2 condition, the characteristics of enzyme activity and gene expression manner for sucrose synthase and beta-1,3-glucanase in developing cotton fiber were more favorable for forming a longer and more steady cellulose accumulation process, and for high strength fiber development.

关 键 词：cotton (Gossypium hirsutum L.) nitrogen FIBER development ENZYME activity gene expression FIBER strength 

分 类 号：S562[农业科学—作物学]