3株耐盐碱促生菌对绿豆根际微生态的影响

Effects of three saline-alkali tolerant growth-promoting bacteria on the rhizosphere microecology of mung bean

利用前期从大庆地区盐碱土中分离得到的3株耐盐碱促生菌(Zobellella、Serratia和Bacillus)进行盆栽试验,研究单株菌和复合菌在盐碱胁迫下对绿豆植株生长的影响,并通过Biolog-Eco板和高通量测序技术检测施用耐盐碱促生菌后绿豆根际土壤细菌代谢功能和细菌多样性变化。结果表明,菌株S29处理后,绿豆根系鲜重较对照增加了19.27%,菌株KM1、NM8和复合菌处理下绿豆的根系鲜重及干重分别增加了25.85%和25.00%,22.93%和22.73%,31.22%和29.55%;接种促生菌能够提高绿豆根际土壤酶活性和土壤细菌的代谢能力,且复合菌处理下的土壤蔗糖酶和脲酶活性最高,分别是对照的1.35倍和1.16倍,绿豆根际土壤细菌在培养240 h时的每孔颜色变化率(AWCD)为:KM1>复合菌>S29>NM8>CK。高通量测序表明,耐盐碱促生菌能够提高绿豆根际土壤细菌多样性和物种丰富度并促进变形菌门、芽单胞菌门和蓝细菌门有益菌的生长。耐盐碱促生菌能够在盐碱胁迫下促进绿豆根系发育,改善根际微生态,缓解了盐碱胁迫对绿豆的伤害,复合菌的促生效果更好。

This pot experiment used 3 saline-alkali tolerant growth-promoting bacteria(Zobellella,Serratia and Bacillus)isolated from the saline-alkali soil in Daqing area to examine the effects of single and compound bacteria on the growth of mung bean plants under saline-alkali stress.The Biolog-Eco board and high-throughput sequencing technology was employed to detect the bacterial metabolic function and bacterial diversity changes in the rhizosphere soil of mung bean after the application of saline-alkali tolerant growth-promoting bacteria.The results showed that compared with the control,the fresh root weight of mung bean root system increased by 19.27%under the treatment of the strain S29.The fresh weight and dry weight of mung bean root system increased by 25.85%and 25.00%,22.93%and 22.73%,31.22%and 29.55%under the treatment of strains KM1,NM8 and compound bacteria,respectively.Inoculation of growth-promoting bacteria improved the soil enzyme activity of mung bean rhizosphere and the metabolic ability of soil bacteria.The soil invertase and urease activities under the compound bacteria treatment were the highest,which were 1.35 times and 1.16 times higher than under the control,respectively.The order of average well color development(AWCD)of mung bean rhizosphere soil bacteria when cultured for 240 h was:KM1>compound bacteria>S29>NM8>CK.High-throughput sequencing showed that saline-alkali tolerant growth-promoting bacteria increased the bacterial diversity and species richness of mung bean rhizosphere soil and promoted the growth of beneficial Proteobacteria,Gemmatimonadetes and Cyanobacteria.Therefore,saline-alkali tolerant growth-promoting bacteria promoted the growth of mung bean roots under saline-alkali stress,improved rhizosphere micro-ecology,and alleviated the damage of saline-alkali stress to mung bean.The compound bacteria had better growth-promoting effects.