Selection,Identification and Growth Promotion of Inorganic Phosphorus-dissolving Bacterial Strains in Rhizosphere of Trifolium repens

白三叶根际解无机磷菌株筛选、鉴定及促生效果研究(英文)

[Objective] The aim was to select and identify inorganic phosphorus-dissolving bacteria in rhizosphere of Trifolium repens,and to research related effects of growth promotion.[Method] Phosphate solubilizing bacteria in rhizosphere of Trifolium repens in Guizhou Province were separated and selected to determine its ability of phosphate solubilizing and IAA secretion,and growth promotion effect.[Result] Phosphate solubilizing bacteria were multiple and varied in rhizosphere of Trifolium repens;solubilizing quantities of phosphorus from calcium phosphate by RW2,RW6 and RW18 were 337.39,447.45 and 462.03 μg/ml;solubilizing quantity was none of linear relation with organic acid;RW2 proved the one secreted most IAA at 12.69 μg/ml,followed by RW18 at 12.34 μg/ml;the three strains were all of Leclercia sp.,but were of none pathogenicity for seedlings of Trifolium repens,instead,a kind of growth promotion was found.Detailedly,RW18 was most effective in growth promotion for Trifolium repens and plant height,root length and weight,and aboveground biomass increased by 110.98%,9.17%,46.17% and 2% respectively.Hence,RW18 is of great potential.[Conclusion] The research provides scientific references for developing phosphate solubilizing bacteria and compound inoculation and develops a novel way to relieve barren soils,save phosphorus resource,reduce environment pollution,and guarantee sustainable development of agriculture and animal husbandry.

[目的]对白三叶根际解无机磷菌株进行筛选、鉴定及促生效果研究,以期为收集优良溶磷菌菌种资源奠定基础。[方法]对贵州省种植的白三叶根际溶磷菌进行分离筛选,并测定其溶磷、分泌IAA能力及促生效果。[结果]白三叶根际存在数量多且溶磷能力各异的溶磷菌株,其中菌株RW2、RW6和RW18对磷酸钙中磷的溶解能力较强,溶磷量分别为337.39、447.45与462.03μg/ml;菌株溶磷量与分泌有机酸量之间无显著线性关系;分泌IAA量最高的是菌株RW2,为12.69μg/ml,其次为菌株RW18,为12.34μg/ml;16SrDNA序列分析将RW2、RW6和RW18菌株初步鉴定为勒克氏菌属(Leclerciasp.),菌株RW18对白三叶幼苗促生效果最好,与对照相比,其株高、根长、根重及地上生物量分别提高110.98%、89.17%、346.17%和242.22%,具有作为促生菌利用开发的潜力。[结论]该研究结果为研发溶磷菌和复合接种剂提供了菌种和科学依据,同时也为缓解贵州地区贫瘠土地磷素供给、节约磷矿等资源、降低环境污染、保护生态环境以及保障农牧业可持续发展开辟了新途径。