Al Resistance Mechanisms in Lespedeza Bicolor
This study aimed to assess the possible Al resistance mechanisms of Lespedeza bicolor by investigating the roles of organic acids secretion and phosphorus ( P) on amelioration of Al toxicity. The roots of L. bicolor (Al-resistant) secreted both malate and citrate after exposure to Al, but roots of Lespedeza cuneata ( Al-sensitive) did not. Neither P starvation nor 30 μM lanthanum induced the secretion of these organic acid anions. When the Al-induced secretion of organic acids was inhibited by 9-anthracene carboxylic acid (an anion-channel inhibitor) , root elongation in L. bicolor was more severely inhibited by Al. Phosphorus application could alleviate the toxic effect of Al on roots growth in the L. bicolor, while no obvious effects were observed in the L. cuneata. Much more Al was accumulated in L. cuneata roots than in L. bicolor roots, the P content in both roots and shoots was increased much more in L. bicolor than in L. cuneata after P application. The amount of Al-induced organic acids secretion of L. bicolor roots precultured with P was much less than that without P application. All results indicated that the secretion of malate and citrate is a specialized mechanism responsible for Al resistance in L. bicolor, P enhances Al resistance in L. bicolor but not in L. cuneata by accumulating higher P and lower Al in roots of L. bicolor than in that of L. cuneata.
Renfang Shen Xiaoying Dong Qingbin Sun Rongfu Chen Jianfeng Ma
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy Research Institute for Bioresources, Okayama University, Chuo 2-20-1, Kurashiki 710-0046, Japan
国际会议
The 7th International Symposium on Plant-Soil Interactions at Low pH(第七届低pH条件下植物-土壤交互作用国际研讨会)
广州
英文
132-133
2009-05-17（万方平台首次上网日期，不代表论文的发表时间）