期刊
ENVIRONMENTAL AND EXPERIMENTAL BOTANY
卷 67, 期 1, 页码 228-234出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.envexpbot.2009.04.004
关键词
Cation-anion balance; N(2) fixation; Nitrate nutrition; Organic acids; Phosphorus deficiency; Proton release; Root exudates
资金
- Chinese Academy of Sciences [KSCX2-YW-N-002]
Little work has been done on root exudation in soybean under P deficiency. This study examined the effect of P supply on release of protons and carboxylates by roots of soybean (Glycine max Heinong 35), and to correlate the release with excess uptake of cations over anions. Plants were either reliant on N(2) fixation or supplied with nitrate and were grown in nutrient solution with 1-50 mu M P for 7 weeks. Release of protons and carboxylates from roots, and concentrations of Ca, Mg, K, Na, P, S, Cl and N in plants were measured weekly from week 4. Unlike in many other species, P deficiency decreased proton release per unit root biomass in N(2)-fixing plants and increased release of hydroxyl ions in nitrate-fed soybean. While P deficiency generally decreased uptake of K, Ca, Mg, S, Cl and P, it increased nitrate uptake per unit root biomass. Irrespective of P supply, amounts of protons released correlated well with excess uptake of cations over anions by the roots. Phosphorus deficiency increased release of carboxylates but the amounts released were small. The results suggest that soybean displays strategies of P acquisition through decreasing proton release which favors P mobilization in acid soils, and increasing root-to-shoot ratio and specific root length. (C) 2009 Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据