选用解磷菌剂改善缺磷土壤磷素的有效性

Improving the availability of soil phosphate by phosphate liberation bacteria

山西省大部分土壤为石灰性土壤,耕地土壤缺磷较严重,施入土壤的化学磷肥极易被固定,为了提高缺磷土壤磷素的有效性,分离筛选的B2和B67菌株研制的解磷菌剂(后称菌剂),首先接种到以磷酸三钙为唯一磷源的培养基中,液体速效磷含量比CK提高12.92倍和9.18倍,然后又接种到其它典型缺磷土壤中,可使土壤速效磷含量较CK增加1.35～3.04倍,且发现其溶磷效果和液体的pH值有关,也与土壤磷酸酶活性和有效活菌数相关,而且菌剂在提高土壤速效磷含量的同时,也提高了土壤速效钾的含量。另外菌剂在缺磷的盆栽和大田试验中取得相同效果,除显著提高土壤速效磷含量,培肥土壤外,同时还有改善作物农艺性状,提高作物产量的功效。

In Shanxi Province, the majority soil is calcareous. And available phosphate content is less in soil. Phosphate fertilizer applied to soil is fixed by soil and cannot be used by plant. In order to increase phosphorus availability, B2 and B67 phosphate liberation bacteria have been successfully isolated to enhance phosphate availability. Culture medium in which tricalcium phosphate was the only phosphorus source, was inoculated with bacteria B2 and B67, soluble phosphorus contents the cultured media with B2 and B67 were 12.92 and 9.18 times higher than that found in control, respectively. When bacteria B2 and B67 were incubated to Shanxi typical soil types, available phosphorus was enhanced and was roughly 1.35-3.04 times higher than that in control soil sample. Phosphate liberation effectiveness was related to solution pH value. Also it was found that phosphate lyolysis was positively related to available number of bacteria and phosphatase activity in soil. Phosphate liberation bacteria could improve both available phosphorus and available potassium in soil. Both field and pot trials demonstrated that phosphate liberation bacteria can increase yield and soil fertility.