多功能植物根际促生菌对东北黑土区玉米的促生效果

应用微生物肥料改良土壤是提高土壤及化肥养分利用率的重要途径之一,但微生物肥料的效果受作物及生态条件的影响较大,目前适合东北地区玉米生产的微生物肥料应用研究较少。本研究针对我国东北黑土类型及气候特点,从当地玉米根际土中筛选分离出5株具有不同程度的合成生长素(IAA)、溶磷、解钾、产铁载体等多功能的植物根际促生菌MZ1、MZ2、MZ3、MZ4和MZ5;生态适应性研究发现5株菌均有不同程度的耐盐、耐干旱、耐酸碱以及耐农药等特性;16S rRNA基因序列分析鉴定出它们分别属于鞘氨醇单胞菌、肠杆菌、假单胞菌、芽孢杆菌和根瘤菌;玉米田间试验结果显示,在减施50%氮肥的条件下, 与不接种对照相比,接种MZ1、MZ3和MZ5可增产19.9%~25.0%。因此,MZ1、MZ3和MZ5具有发展为适合东北地区土壤和气候环境的玉米微生物肥料的潜力。

Effects of multifunctional plant rhizosphere promoting bacteria on maize growth in black soil areas in Northeast China

The application of microbial fertilizer plays an important role in improving soil restoration and fertilizer utilization. The effects of microbial fertilizer are greatly affected by crop genotypes and ecological conditions. Little is known about the effects of microbial fertilizers on maize production in Northeast China. To develop microbial fertilizer specific to the black soil and the climate characteristics of Northeast China, we isolated five plant rhizosphere-promoting bacteria (PGPR), named as MZ1, MZ2, MZ3, MZ4 and MZ5, with different degrees of biological functions such as IAA synthesis, phosphate-solubilizing, potassium-solubilizing and siderophore-releasing, from the rhizosphere of maize field. The analysis of ecological adaptability showed that those five strains differed in salt resistance, drought tolerance, acid and alkali resistance, pesticide resistance. The 16S rRNA gene sequences analysis showed that the strains MZ1, MZ2, MZ3, MZ4 and MZ5 belonged to the genus of Sphingomonas, Enterobacter, Pseudomonas, Bacillus and Rhizobium, respectively. In maize field experiment with 50% nitrogen fertilizer reduction, the inoculation with MZ1, MZ3 and MZ5 increased grain yield by 19.9%-25.0%. MZ1, MZ3, and MZ5 could be used as microbial fertilizers for maize in Northeast China.