钙离子胁迫对薏米幼苗生长的影响

Effects of Calcium Stress on the Growth of of Coix lacryma-jobi L.var.ma-yuen Seedlings

为解析钙离子胁迫对薏米幼苗生长影响的生理机制,以薏米幼苗为研究对象,探索其在不同浓度钙离子胁迫下的生理变化。薏米在培养至大部分幼苗2片叶片展开时,分别浇施含有不同钙量的霍格兰德营养液,处理7 d,根据薏米幼苗叶片的形态变化确定处理浓度,同时对薏米幼苗的含水量、总可溶性糖含量、丙二醛(MDA)含量、过氧化氢酶(CAT)活性、过氧化酶(POD)活性、超氧化物歧化酶(SOD)活性进行测定。结果显示随着钙胁迫浓度增加,植株生长受到的抑制程度逐渐加强,植株高度逐渐降低,叶片的颜色变黄及叶片卷曲程度加深。同时,薏米幼苗的含水量逐渐降低,MDA含量和SOD活性逐渐升高,总可溶性糖含量、CAT活性、POD活性、均呈先升高后下降的趋势。表明钙离子对薏米幼苗主要产生渗透胁迫作用。

In order to analyze the physiological mechanism of the effect of calcium stress on the growth of Coix lacryma-jobi L.var.ma-yuen seedlings,the physiological changes of Coix lacryma-jobi L.var.ma-yuen seedlings under different concentrations of calcium ions stress were observed.When most of the seedlings were cultured until the two leaves spread out,Hoagland nutrient solution containing different amounts of calcium ions was poured and treated for 7 days.The treatment concentration was determined according to the morphological changes of the leaves of Coix lacryma-jobi L.var.ma-yuen seedlings.At the same time,the water content,total soluble sugar content,malondialdehyde(MDA)content,catalase(CAT)activity,peroxidase(POD)activity and superoxide dismutase(SOD)activity of Coix lacryma-jobi L.var.ma-yuen seedlings were measured.The results showed that with the increase of calcium stress concentration,the inhibition degree of plant growth gradually strengthened,the height of plant gradually decreased,and the color of leaves turned yellow and the curl degree of leaves deepened.At the same time,the water content in the Coix lacryma-jobi L.var.ma-yuen seedlings decreased gradually,while the MDA content and SOD activity increased gradually.The total soluble sugar content,CAT activity and POD activity all showed a trend of increasing at first and then decreasing.Calcium ions mainly exerted osmotic stress on Coix lacryma-jobi L.var.ma-yuen seedlings.