[Effects of copper on rhizobia-Acacia auriculaeformis symbiotic association].
The effects of different levels of Cu2+ were studied individually on the growth of two Rhizobium strains and host plant growth, nodulation(%) and nitrogen fixation activity in A. auriculaeformis under solution culture conditions so as to explore a probability of utilization of the genus Acacia in revegetation of Cu(2+)-contaminated land. The results shows that Rhizobium sp. (Acacia auriculaeformis) had more stronger tolerance to Cu2+ iron than Rhizobium sp(Lespedeza formosa). The values of EC50 respectively achieved 0.129 mmol for Rhizobium sp. and 0.151 mmol for the N2-fixation activity. When the concentration of Cu2+ was over 0.50 mmol, N2-fixation activity had been inhabited thoroughly. Although the formation of nodules of Acacia auriculaeformis could continued, the growth of host plant had been inhibited with the appearance such as stunting, chlorosis. Between the noinodulating but adding nitrogen treat group and the inodulating without any nitrogen resource treat group, when Cu2+ < 0.125 mmol, the latter group showed better growth for A. auriculaeformis. There were higher contents of Cu in the underground tissues than in aboveground tissues.
Nie
Xiangping
X
School of Life Sciences, Zhongshan University, Guangzhou 510275.
Lan
Chongyu
C
Zhang
Zhiquan
Z
Shu
Wensheng
W
Huang
Minghong
M
D000045:Acacia / Q000187:drug effects*; D003300:Copper / Q000494:pharmacology*; D012231:Rhizobium / Q000187:drug effects*; D013559:Symbiosis / Q000187:drug effects*
D003300:Copper