一株溶磷真菌的筛选及相关促生特性初探

Screening and identification of a high-efficient phosphate-solubilizing fungus Penicillium decumbens and analysis of its phosphate-solubilizing characteristics

磷是植物生长发育不可缺少的营养元素之一,由于土壤的固定化作用而含量极低,成为限制作物产量的主要因素.溶磷菌能够帮助植物从土壤中将难溶性磷转变为可溶性有效磷.笔者从胡枝子根际土壤中分离筛选出一株高效的溶磷真菌X1,对其菌种进行鉴定,同时对其溶磷能力及其他促生能力进行了测定.结果表明:该株高效溶磷真菌X1经鉴定为斜卧青霉菌属(Penicillium decumbens);对不同难溶性磷酸盐均具有溶解能力,对磷酸钙的溶磷量可达2 003.95 mg·L^(-1);具有分泌IAA、ACC脱氨酶及产氨的能力,且具有一定的固氮和降解纤维素的能力,纤维素酶活力为34.41 U·mL^(-1).该株高效溶磷真菌斜卧青霉X1具有作为溶磷微生物菌剂的开发潜力.

Phosphorus is one of the essential nutrient elements for plant growth and development,which is the main limited factor for cropproduction.However,due to the immobilization of soil,the content of available phosphorus in soil is extremely low.Phosphorus-solubilizing bacteria can help plants transform insoluble phosphorus into soluble phosphorus from soil.In this study,a highly efficient phosphorus-solubilizing fungus was screened from soil,and its phosphorus-solubilizing ability and other growth-promoting ability were determined.The results showed that a high-efficient phosphorus-dissolving fungus X1 was isolated and screened from the rhizosphere soil of Lespedeza bicolor and identified as Penicillium decumbens;Penicillium decumbens X1 had the capability of dissolving different insoluble phosphates,and the phosphorus dissolving amount for calcium phosphate could reach 2003.95 mg·L^(-1);meanwhile Penicillium decumbens X1 had the ability to secrete IAA,ACC deaminase and ammonia production,and a certain ability of nitrogen fixation and cellulose degradation,(the cellulase activity was 34.41 U·mL^(-1)).In brief,the Penicillium decumbens X1 has the potentials as the microbial inoculum to improve available phosphorus resources.