Effects of Rhizosphere Dissolved Oxygen Content and Nitrogen Form on Root Traits and Nitrogen Accumulation in Rice

作     者：ZHAO Feng XU Chun-mei ZHANG Wei-jian ZHANG Xiu-fu LI Feng-bo CHEN Jian-ping WANG Dan-ying ZHAO Feng1,2,3,#,XU Chun-mei1,#,ZHANG Wei-jian2,ZHANG Xiu-fu1,LI Feng-bo1,CHEN Jian-ping3,WANG Dan-ying1(1China National Rice Research Institute,Hangzhou 310006,China;2Institute of Applied Ecology,Nanjing Agricultural University,Nanjing 210095,China;3Institute of Food Crops,Hubei Academy of Agricultural Sciences,Wuhan 430064,China;#These authors contributed equally to this paper)

作者机构：China Nationa l Rice Resea rch InstituteHangzhou 310006China Institute of Applied EcologyNanjing Agricultura l Univer sityNanjing 210095China Institute of Food CropsHubei Academy of Agricultura l SciencesWuhan 430064China 

出 版 物：《Rice science》 (水稻科学(英文版))

年 卷 期：2011年第18卷第4期

页      面：304-310页

学科分类：0710[理学-生物学] 0831[工学-生物医学工程（可授工学、理学、医学学位）] 09[农学] 0901[农学-作物学] 0836[工学-生物工程] 0902[农学-园艺学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.30571102) the Key Projects in the National Science & Technology Pillar Program of China(Grant No.2006BAD02A13) the Provincial Natural Science Foundation of Zhejiang(Grant No.Y3100270) 

主　　题：nitrogen form dissolved oxygen rice root nitrogen accumulation 

摘      要：Dissolved oxygen and nitrogen form have important effects on rice root growth and nitrogen availability. An indica hybrid rice, Guodao 1, and a conventional japonica rice, Xiushui 09, were cultured in hypoxic nutrient solution with NH 4 NO 3 or (NH 4 ) 2 SO 4 as the nitrogen source for six weeks in pools. A portion of the Guodao 1 seedlings after treatment in the pools for four weeks were transferred to a split-root system at different dissolved oxygen contents and cultured for an additional two weeks. Biomass, root morphological traits and nitrogen accumulation were recorded. Under the low rhizosphere dissolved oxygen content (0–1.0 mg/L), plant biomass was significantly increased under NH 4 NO 3 -N supply by about 69% in Guodao 1 and 41% in Xiushui 09 compared with those under NH 4 + -N alone. Similar results were observed for root number, maximum root length, root dry weight and root activity. Nitrogen accumulations in roots and shoots were increased by 60% and 52% for Guodao 1, and by 41% and 33% for Xiushui 09, respectively, in the NH 4 NO 3 -N treatment. In the split-root system, the high rhizosphere dissolved oxygen content (8.0–9.0 mg/L) promoted root growth and development. Root biomass was increased by 21.6%, root number by 27%, maximum root length by 14%, and root volume by 10%. Moreover, nitrogen accumulation in roots was increased by 11% under high rhizosphere oxygen conditions. In conclusion, enhanced dissolved oxygen content and combined ammonium-nitrate nitrogen source have positive effects on root growth and nitrogen accumulation of rice plants.