解淀粉芽孢杆菌HM618对镉胁迫下小麦幼苗生长的影响

Effects of Bacillus amyloliquefaciens HM618 on the growth of wheat seedlings under cadmium stress

为了探究根际促生菌解淀粉芽孢杆菌HM618对重金属镉胁迫下小麦幼苗生长的影响,采用不同体积的解淀粉芽孢杆菌HM618发酵液处理不同程度镉胁迫下的小麦幼苗,测定根长、株高、叶绿素、可溶性蛋白、可溶性糖、脯氨酸和丙二醛含量等生长和生理指标.结果表明:不同施加量的解淀粉芽孢杆菌HM618发酵液对小麦幼苗均有一定的促生作用,尤其是对根部的促生作用显著.镉胁迫会导致小麦幼苗的叶绿素和可溶性蛋白含量下降,可溶性糖、脯氨酸和丙二醛含量增加,在解淀粉芽孢杆菌的作用下,小麦幼苗的叶绿素和可溶性蛋白含量均显著增加,而可溶性糖、脯氨酸和丙二醛的含量均减少.总的来看,解淀粉芽孢杆菌HM618对小麦幼苗遭受的镉胁迫具有缓解作用,且发酵液的使用量越大,缓解效果越显著;小麦幼苗遭受的镉胁迫程度越严重,解淀粉芽孢杆菌的缓解效应越显著.

In order to explore the influence of Bacillus amyloliquefaciens HM618 on the wheat seedlings under heavy metal cadmium stress,the seedlings under different degrees of Cd stress were treated with different volumes of B. amyloliquefa-ciens HM618 fermentation broth. The growth and physiological indexes,including root length,plant height,chlorophyll content,soluble protein content,soluble sugar content,proline content and malondialdehyde content,were measured. The results showed that all the fermentation broth of B. amyloliquefaciens HM618 with different volumes had growth-promoting effect on the wheat seedlings,especially on the roots. Cd stress can decrease the contents of chlorophyll and soluble protein of seedlings,and enhance the contents of soluble sugar,proline and malondialdehyde. Under the effects of B. amyloliquefaciens HM618,the contents of chlorophyll and soluble protein increased significantly,and the contents of soluble sugar,proline and malondialdehyde decreased. Overall,B. amyloliquefaciens HM618 can relieve the Cd stress of wheat seedlings,and the effect increased with the increase of fermentation broth dosage;the more severity the seedlings sustained,the more significant the mitigation effect of B. amyloliquefaciens HM618.