为筛选优良的玉米根内促生菌,以大庆市苏打盐碱地玉米根系为材料,以组织研磨法、平板划线法共分离纯化207株根内细菌,通过促生能力测定,筛选出3株能力较强的菌株,验证其对玉米幼苗和盆栽的促生效果。结果表明,筛选出具有解磷、固氮、产铁载体功能、产植物激素IAA、耐受苏打盐碱(200~250 mmoL·L-1 NaHCO3和Na2CO3,摩尔比为9:1；pH值9.1)的能力的三株内生细菌鉴定为暹罗芽孢杆菌(Bacillus siamensis YM87)、维氏芽孢杆菌(Bacillus wiedmannii YM107)、贝莱斯芽孢杆菌(Bacillus velezensis YM114)。发芽实验发现三株根内生细菌均对玉米有促生效果,YM114浸种处理后种子根尖数、根长、根表面积、体积和幼苗长分别提高26.8%、42.1%、34.6%、12.6%、9.1%,具有促生功能,盆栽实验发现三株根内生细菌在盆栽前期均可显著促生,但YM114处理组的穗长、穗粗、轴长、轴重、百粒重分别增加了14.4%、15.7%、17.3%、27.9%、9.1%,促生增产效果明显。三株根内生细菌均具有明显促生增产潜力。

In order to screen excellent growth-promoting bacteria in maize roots, 207 strains of bacteria in roots were isolated and purified by tissue grinding method and plate streaking method from maize roots in soda saline-alkali land of Daqing City.Three strains with strong growth-promoting ability were screened by growth-promoting ability determination, and their growth-promoting effects on maize seedlings and pots were verified. The results showed that it had the functions of phosphate solubilization, nitrogen fixation, siderophore production, plant hormone IAA production, tolerance to soda saline-alkali ( 200 ~ 250 mmoL · L-1 NaHCO3 and Na2CO3, molar ratio of 9 : 1 ). The three endophytic bacteria with the ability of pH 9.1 were identified as Bacillus siamensis YM87, Bacillus wiedmannii YM107 and Bacillus velezensis YM114. In the germination experiment, it was found that all three root endophytic bacteria had a growth-promoting effect on maize. After YM114 soaking treatment, the number of root tips, root length, root surface area, volume and seedling length of seeds increased by 26.8 %, 42.1 %, 34.6 %, 12.6 % and 9.1 %, respectively, which had a growth-promoting function. In the pot experiment, it was found that all three root endophytic bacteria could significantly promote growth in the early stage of pot experiment, but the ear length, ear diameter, axis length, axis weight and 100-grain weight of YM114 treatment group increased by 14.4 %, 15.7 %, 17.3 %, 27.9 % and 9.1 %, respectively, and the growth-promoting and yield-increasing effect was obvious. The three root endophytic bacteria have obvious potential for promoting growth and increasing yield.

国家重点研发项目（2022YFD1500202）黑龙江八一农垦大学三纵（基础培育）项目（ZRCPY202218）