铝胁迫条件下镧对百喜草幼苗根系生长的影响

摘要

Lanthanum (La) is one of the most vital and active rare earth elements.It can promote seed germination,increase crop output,and enhance plant resistance to environmental stresses.Paspalum notatum,a warm season turfgrass commonly used for conserving soil and water in Guangzhou,was selected to study the effect of La on root growth.Seven-day-old seedlings of P.notatum were grown in hydroponic conditions in an acid solution containing 0.9 μmol/L AP+ with and without 0.3 μmol/L La3+.Root morphology,the root dry weight/fresh weight ratio,and root activity were evaluated after 2,4,and 6 d of treatment.The addition of La3+ to the acidic Al3+ solution resulted in increased axial root length,root surface area,number of root tips,root volume,and root activity of P.notatum seedlings.These findings indicated that La can promote the root growth of P.notatum seedlings under Al3+ stress.%镧是稀土元素中最重要和最活泼的元素,具有促进种子萌发、提高作物产量和增强抵御逆境胁迫等作用.研究以华南地区水土保持常用的百喜草幼苗为材料,通过水培实验探究在酸性铝胁迫条件下镧对百喜草幼苗根生长的影响.实验在0.9 μmol/L Al3+的酸性铝胁迫水培条件下,以添加0.3 μ.mol/L的La3+作为处理,在水培的第2,4,6天,分别测定根系形态、根干鲜比、根茎比、根系活力.结果表明,在酸性铝胁迫水溶液中添加La3+,可提高幼苗的主根长、根表面积、根尖数、根体积、根干鲜比、根茎比、根系活力,说明在酸性铝胁迫条件下,镧元素可以促进百喜草幼苗根系的生长.