ÃÞ »¨ ѧ ±¨      Cotton Science        2009£¬21(6)£º508-514

 

 

Effects of Water and Nitrogen on Cotton Root Architecture under Film Drip Irrigation
XIE Zhi-liang1£¬2£¬3£¬TIAN Chang-yan1£¬3*£¬BIAN Wei-guo1£¬3
(1.Xinjiang Institute of Ecology and Geography£¬Chinese Academy of Science£¬Urumqi,Xinjiang 830011£¬China£»2. Graduate University of Chinese Academy of Science£¬Beijing 100049£¬China£»3.Key Laboratory of Oasis Ecology and Desert Environment, Xinjiang Institute of Ecology and Geography,Chinese Academy of Science, Urumqi 830011£¬ China)

Abstract£ºResponses of nitrogen and water on root architecture were investigated by layered digging. The results indicated that: with the increasing of irrigation amount, root dry weight increased, root length and root surface area reduced. Root dry weight and root length decreased in top soil layers and increased in deep soil layers. Root surface area decreased in whole soil layers. High nitrogen supply had obvious inhibitory effects, manifested as the decreasing of root dry weight and root length and root surface. Water and nitrogen interaction had significant influences on root dry weight, average root length density, root dry weight of subsurface layers,root length and root surface area of top soil layers and deep soil layers. When irrigation amount was 300 mm, root dry weight and the distribution of root dry weight in subsurface layers reached the maximum at 276 kg¡¤hm-2 nitrogen supply. Nitrogen supply had no effect on average root length density. Low nitrogen and high nitrogen had promoting effect on the increasing of root length and root surface area. When irrigation amount was 600 mm , root length of deep soil layers reached the maximum at 276kg¡¤hm-2 nitrogen supply. With nitrogen supply increased, root surface area of whole soil layers increased. Water is the main factor of effect yield. Water stress weakened the yield increasing effect of nitrogen. Nitrogen promoted the yield increasing effect of water, but too much nitrogen supply decreased this effect.
Key words£ºwater and nitrogen interaction; root architecture; cotton     [Full Text, 3309KB]