盐胁迫下产多胺细菌ccx5对大豆萌发及幼苗生长的影响

Effects of Polyamine-produced Bacteria ccx5 on the Growth of Soybean Seedlings Under Salt Stress

以大豆为实验材料,探究盐胁迫下产多胺细菌ccx5对大豆萌发及幼苗生长的影响。用营养液沙培的方法,研究了6种盐胁迫(浓度分别为0,30,60,90,120,150 mmol·L^(-1))对大豆种子吉育47(JY47)萌发的影响。结果表明低浓度盐胁迫(30,60,90 mmol·L^(-1))促进大豆JY47萌发,而高浓度盐胁迫(120,150 mmol·L^(-1))抑制大豆JY47的萌发。加入产多胺菌后在无盐胁迫及低盐胁迫下对大豆JY47的萌发影响不明显,而在高盐胁迫下有促进作用。采用营养液沙培法在高盐(120mmol·L^(-1))胁迫下进行幼苗生长实验,结果表明:在高盐胁迫下,大豆JY47幼苗的生长发育受到了明显的抑制,且MDA的含量和SOD活性都显著提高,叶绿素含量减少。接种多胺细菌ccx5的实验组大豆幼苗的生长抑制得到了缓解,MDA的含量有所下降,叶片中的叶绿素含量和SOD活性高于盐胁迫组。实验表明:在氯化钠胁迫下,多胺细菌ccx5参与大豆JY47幼苗的生长代谢过程,提高了大豆幼苗对盐分胁迫的抗性。

Soybean was used as experiment material to explore the effects of polyamine-generated bacteria named ccx5 on growth of soybean seedlings under salt(NaCl)stress.The effects of 6 different concentrations(0,30,60,90,120,150 mmol·L-1)of salt on soybean(JY47)seed germination were researched by the method of sand culture added with nutrient solution.The results showed that the low concentrations of salt(30,60,90 mmol·L-1)prompted soybean germination and high concentrations of salt(120,150 mmol·L-1)inhibited it.Polyamine-generated bacteria had no significant effects on the condition of no salt and low salt concentrations(30,60,90 mmol·L-1),however,it promoted the growth of seedlings on the condition of high salt concentrations(120,150 mmol·L-1).The seedling growth experiments were carried out under the condition of high salt stress(120 mmol·L-1)by the method of sand culture added with nutrient solution.The results showed that under this salt stress,the growth and development of soybean JY47 seedlings were significantly inhibited,and the content of MDA and SOD activity were significantly increased,whereas the chlorophyll content decreased.In addition,compared with the salt stress group,the growth inhibition of soybean JY47 seedlings incubated with bacteria ccx5 was alleviated,content of MDA was decreased,and content of chlorophyll and SOD activity in leaves were higher in the ccx5 treatment group.The results showed that under NaCl stress,polyamine-generated ccx5 was involved in the growth and metabolism of soybean JY47 seedlings,and increased the resistance of soybean seedlings to salt stress.