巨柏根际多功能溶磷菌W13对植物生长的促生效果研究

Study on the Growth-Promoting Effect of the Multifunctional Phosphate-Solubilizing Bacterium W13 in the Rhizosphere of Cupressus Gigantean

从巨柏根际土壤中分离多功能溶磷促生菌株,为高原环境下多功能溶磷菌的收集和研究提供研究基础。本研究从西藏自治区林芝市朗县采集巨柏根际土壤样本,采用梯度稀释法筛选溶磷菌,并结合溶磷圈法和钼锑抗比色法测定溶磷能力,选出溶磷能力较好的菌株,并对IAA、固氮、解钾等多种促生特性进行测定,最终筛得具有多功能的溶磷菌,通过盆栽实验对溶磷菌的促生效果进行验证,并结合形态特征、革兰氏染色和16S rDNA基因序列对菌株进行鉴定。W13具有产IAA、铁载体、固氮、解钾等多种促生特性,为非脫羧勒克菌(Leclercia adecarboxylata)。经盆栽促生试验结果表明,W13对油菜和青稞具有不同程度的促生作用,与对照组相比W13有效提高了油菜植株的根长、株高、鲜重和干重,并分别增长了119%、55.30%、157%和50%。青稞株高效果显著增长了44.80%。多功能溶磷细菌W13对油菜和青稞都具有一定的促生作用,因此该菌具有作为生物肥料的潜力,用于植物生产。

The objective of this study was to isolate phosphorus-solubilizing bacterial strains with multiple growth-promoting functions from the rhizosphere soil of Cupressus gigantean,and to provide a basis for collection and investigation of multi-functional phosphorus-lytic bacteria in high-altitude environment.In this research,a soil sample was collected from the rhizosphere of Cupressus gigantean in Lang County,Nyingchi City,Tibet Autonomous Region.Phosphorus-dissolving bacteria were screened using the gradient dilution method.The phosphorus-soluble ability of the strains was determined using the phosphorus-soluble circle method and the molybdenum antimony anti-colorimetric method.Strains displaying notable phosphorus-solubilizing capacity were selected,and various growth-promoting traits,including IAA production,nitrogen fixation,and potassium solubilization,were assessed.Finally,a multifunctional phosphorus-solubilizing bacterium named W13 was identified as Leclercia adecarboxylata.W13 exhibited several growth-promoting characteristics,including IAA production,siderophore production,nitrogen fixation,and potassium solubilization.Pot experiments confirmed that W13 had a significant growth-promoting effect on both rapeseed and barley.In comparison to the control group,W13 led to a substantial increase in root length,plant height,fresh weight,and dry weight for rapeseed plants by 119%,55.30%,157%,and 50%,respectively.Moreover,the height of barley plants increased significantly by 44.80%.The multi-functional phosphorus-soluble bacterium,W13,demonstrated significant growthpromoting effects on rapeseed and barley,suggesting its potential use as a biofertilizer for plant production.