Abstract: In order to investigate the growth promotion effects of 5 strains of azotobacter and 5 strains of phosphorus solubilizing bacteria on 3 kinds of cultivated forages in high cold area， 14 groups of single and compound inoculants were used to inoculate corn （Zea mays L.）， oat （Avena sativa L.） and alfalfa （Medicago Sativa L.）， and plant height， biomass and root morphology were determined in this study. The results showed that there were differences in the growth indices of corn， oat and alfalfa. Among them， compound inoculant A+B+F had significant growth promoting effects on aboveground biomass， underground biomass， root total length and root surface area of corn， which were significantly higher than those on other treatments （P<0.05）. Compound inoculants B+G+H and A+B+F had obvious growth-promoting effects on plant height， aboveground biomass， underground biomass， root length， root diameter， root volume and root surface area of oat. In the alfalfa inoculation experiment， the effects of compound inoculant A+F on plant height， aboveground biomass， underground biomass， root length， root diameter， root volume and root surface area of alfalfa were significantly higher than those on other treatments and controls （P<0.05）. In short， the compound inoculant had more potential to develop microbial fertilizer than the single strain， which could provide a new idea for applied agriculture.

Key words: Plant growth promoting rhizobacteria, Alpine area, Cultivated forage, Promoting effect

摘要： 为了探究5株固氮菌和5株溶磷菌对高寒区3种栽培饲草的促生效果，本研究以玉米（Zea mays L.）、燕麦（Avena sativaL.）和苜蓿（Medicago SativaL.）为研究对象，用14组单一接菌剂和复合接菌剂进行盆栽接种试验，测定植物的株高、生物量及根系形态。结果表明：各接菌剂对盆栽玉米、燕麦、苜蓿的生长指标测定结果存在差异，其中，复合接菌剂A+B+F对玉米植株的地上生物量、地下生物量、根系总长和根表面积的促生效果较为显著，显著高于其他处理和对照（P<0.05）；复合接菌剂B+G+H，A+B+F对燕麦的株高、地上生物量、地下生物量、根长、根直径、根体积、根表面积均产生明显的促生作用；在苜蓿接种试验中，复合接菌剂A+F对苜蓿的株高、地上生物量、地下生物量、根长、根直径、根体积、根表面积的影响较大，显著高于其他处理和对照（P<0.05）。因此，复合接菌剂比单一菌株具有研制微生物肥料的潜质，可为应用农业提供新思路。

关键词: 植物根际促生菌, 高寒区, 栽培饲草, 促生效果