Nitrate Nutrition But Not Rhizosphere pH Enhances Zinc Hyperaccumulation in Thlaspi caerulescens (Prayon)
The Zn phytoremediation potential can be improved by applying nitrate fertilizers to increase the biomass and Zn content of shoots. However, it is uncertain whether this is due to assimilation of the nitrate specifically or as a consequence of a pH increase in the rhizosphere induced by nitrate uptake. A solution culture experiment was conducted to understand the effect of nitrogen form and solution pH on Zn phytoextraction and element composition in roots and shoots of Thlaspi caerulescens (Prayon). The plants were grown with basal nutrients including 300 μmol·L-1 Zn and supplied with (NH4) 2SO4, NH4NO3 or Ca(NO3)2. The solutions were maintained at pH 4.5 or 6.5. The provision of NO3- rather than NH4+ was more effective at either pH 4.5 or 6.5 in maximizing Zn accumulation in the shoots. The effect of N form on Zn and Ca accumulation was confirmed to be similar. The lower concentration of N in NO3-fed shoots suggests that it is the N compounds within the plant, and not the quantity of N, which increased Zn tolerance and promoted hyperaccumulation in T. caerulescens.
Ammonium (NH4+) Nitrate (NO3-) Phytoeztraction Solution pH Thlaspi caerulescens Zinc (Zn)
Alison C Monsant Gaelle Ng Kam Chuen Yaodong Wang Caixian Tang
Department of Agricultural Science,La Trobe University,Bundoora,Australia School of Botany,University of Melbourne,Australia
国际会议
杭州
英文
127-129
2009-10-10（万方平台首次上网日期，不代表论文的发表时间）