水培条件下不同磷水平对毛竹实生苗生长发育的影响

以毛竹(Phyllostachys edulis)实生苗为材料,采用Hoagland营养液水培方法,研究不同磷浓度下毛竹生长、根系发育、激素含量等的差异。结果表明:磷浓度较低时,可以促进毛竹实生苗根系长度及根系总表面积的增长。随着磷浓度的增加,实生苗生物量干重及根冠比呈先上升后下降趋势,磷浓度为1 mmol L-1时达到最大。无磷处理时,根中的IAA、ZR、GA3和ABA等4种内源激素含量随着处理时间的延长均先升高再降低;其他浓度磷处理根中IAA、ZR和GA3(0.5 mmol L-1磷除外)含量随着处理时间的延长大致呈先降低后升高的趋势,而ABA(0.5 mmol L-1磷除外)含量随着处理时间的延长变化不明显。不同浓度磷处理,叶片中IAA、GA3和ABA含量总体上呈下降趋势,ZR含量总体上呈上升趋势。以上结果表明不同浓度的磷处理对毛竹内源激素含量的变化有显著的影响,而内源激素含量变化与毛竹实生苗根系变化密切相关。

Effects of Different Phosphorus Concentration on Growth and Development of Moso Bamboo

The effects of different phosphorus concentration on growth of moso bamboo (Phyllostachys edulis) were studied under hydroponic condition. With the decreasing phosphorus concentration, root length and root surface area was increased. The dry biomass and root to shoot ratio of moso bamboo tended to rise at first and then fall as phosphorus concentration increased. When the concentration of phosphorus was 0 mmol L^-1, the contents of the four endogenous hormone in root rose firstly and fall later. The contents of IAA, ZR and GA₃ in root fall firstly and rose later in other concentrations. The content of ABA in roots did not change obviously (except for 0.5 mmol L^-1). The contents of IAA, GA₃ and ABA in leaves were decreased, while ZR increased. Therefore, phosphorus concentration had significant effect on the contents of endogenous hormones in moso bamboo, which influenced growth of roots of moso bamboo.