蒙脱石负载溶磷菌联合磷肥对茶园土壤磷的调控

Regulation of phosphorus in tea garden soil with montmorillonite supported phosphate-solubilizing bacteria combined with phosphate fertilizer

我国南方土壤磷素低、单施磷肥效果差,采用以溶磷菌为基础的调控手段能有效缓解上述问题。以庐山云雾茶园土壤为研究对象,探究溶磷菌(PSB)、磷肥(过磷酸钙P1、钙镁磷肥P2)、负载材料(Mt@PSB)及其组配剂对土壤速效磷含量的调控效果与作用机制。结果表明:茶树为喜酸植物,钙镁磷肥(P2)及其组配剂碱性强,不适于茶园土壤调控。溶磷菌(PSB)、磷肥(P1)、负载材料(Mt@PSB)及其组配剂(PSB+P1、Mt@PSB+P1)调控后,茶园土壤pH均处于适宜茶树生长的范围(4.5~6.5),处理后土壤速效磷含量和酸性磷酸酶活性均显著高于对照,培养45 d后速效磷含量分别增加21%、30%、18%、41%和63%,酸性磷酸酶活性分别增加14%、104%、10%、47%和107%。极差分析结果表明,上述3个因子对土壤磷的改善效果依次为Mt@PSB、PSB和P1,且Mt@PSB+P1的效果最佳。磷形态分析结果表明,PSB、Mt@PSB、P1主要通过将有机磷矿化为无机磷提高其有效性。PSB+P1和Mt@PSB+P1组配下,土壤速效磷含量的增加主要表现为Ca-P和Fe-P含量的增加。

Low phosphorus content and inefficient phosphorus fertilizer are the soil problems in the southern China.The control methods based on phosphate-solubilizing bacteria(PSB)will effectively alleviate these prob-lems.Taken Lushan tea garden soil as test sample to explore the regulation effects and mechanism of PSB,phos-phate fertilizer(superphosphate P1,calcium magnesium phosphate P2),supported materials(Mt@PSB)and their combinations on soil available phosphorus(AP)content.The results showed that P2 was not suitable for tea gar-den,because P2 and its compounds were alkaline,but tea plants were acidophilic plants.After the application of PSB,P1,Mt@PSB and their combinations(PSB+P1、Mt@PSB+P1),the soil pH of tea garden was just in the suitable range for tea tree growth(4.5-6.5).The content of AP and acid phosphatase activity of soil after the treat-ments were significantly higher than control.After 45 days’incubation,the content of AP increased by 21%,30%,18%,41%and 63%,respectively,the acid phosphatase activity increased by 14%,104%,10%,47%and 107%,respectively.The range analysis results showed that the improvement effects of the three factors on soil AP were Mt@PSB,PSB and P1 in turn,and Mt@PSB+P1 performed the best.The result of phosphorus fractions analysis showed that PSB,Mt@PSB and P1 improved the content of AP mainly by mineralizing organic phosphorus into inorganic phosphorus.Under the regulation of PSB+P1 and Mt@PSB+P1,the increase of AP content was mainly reflected by the increase of Ca-P and Fe-P content.