铅胁迫对扁豆种子萌发及幼苗生长的影响

Effects of Lead Stress on Seed Germination and Seedling Growth of Lablab purpureus

用浓度为0、20、50、100、200 mg/L的铅溶液分别处理3个扁豆品种种子(紫边眉豆、猪耳朵扁豆、红月紫扁豆),研究梯度浓度铅胁迫对扁豆种子萌发和幼苗生长的影响。结果表明,20~50 mg/L铅处理对3个扁豆品种种子萌发有促进作用,铅浓度高于100 mg/L时有抑制作用;铅浓度越高,3个扁豆品种种子的根长度和芽长度越短、根鲜重和芽鲜重越低,其中对根长度抑制作用显著、对芽长度的影响很小。随铅浓度的提高,猪耳朵扁豆幼苗的可溶性蛋白质含量和丙二醛(MDA)含量缓慢增加,可溶性糖含量却先升后降;紫边眉豆幼苗的可溶性蛋白质含量和丙二醛(MDA)含量逐步增加,可溶性糖含量先升后降;红月紫扁豆幼苗的丙二醛含量逐渐增加,可溶性蛋白质和可溶性糖含量先上浮后下滑。

In this study,three varieties of Lablab purpureus(Linn.)Sweet seed(‘purple side’,‘porcine sear’and‘red moon purple’)were treated with 0,20,50,100 and 200 mg/L lead solutions respectively.The effects of concentration gradient lead stress on the seed germination and the seedling growth of three varieties were determined.The results showed that 20-50 mg/L lead treatment promoted seed germination of three varieties,and>100 mg/L lead treatment had an inhibitory effect.With the increase of lead concentration,the root length,shoot length,root fresh weight and fresh weight of three varieties showed a downward trend.Lead stress significantly inhibited the root length,and had less effect on shoot length.With the increase of lead concentration,the soluble protein content and malondialdehyde(MDA)content of‘porcine sear’increased gradually,while the soluble sugar content increased first and then decreased;the content of soluble protein and MDA of‘purple side’increased gradually,while the soluble sugar content increased first and then decreased;the MDA content of‘red moon purple’gradually increased,while the content of soluble protein and MDA sincreased first and then decreased.