Department of Soil and Land Resources, Faculty of Agriculture The University of Papua.
Department of Agronomy Faculty of Agriculture The University of Papua.
Microbes Environ. 2022;37(1). doi: 10.1264/jsme2.ME21041.
Phosphorus (P) is an essential macronutrient for plant growth and is mainly present in agricultural soil in unavailable forms. Phosphate-solubilizing microorganisms (PSMs) increase soil P availability. The objective of the present study was to assess the population and type of PSMs and their relationships with soil characteristics in the agricultural soil of Manokwari. Twenty-one composite soil samples (0-20 cm) were collected at the rhizospheres of plants in the Prafi and Masni Districts. A dilution technique and plate count method on Pikovskayas agar medium were used to examine the PSM population, phosphate-solubilizing index (PSI), and various soil properties. The results obtained showed that the total population of phosphate-solubilizing bacteria ranged between 25×10 and 550×10 CFU g of soil, while that of phosphate-solubilizing fungi was between 2.0×10 and 5.0×10 CFU g of soil at all locations. The PSI of the isolates ranged between 1.1 to 3.6 mm, with the most efficient and highest PSI being obtained for Bacillus sp. (strain 8) and the lowest for Pseudomonas sp. (strain 15). Six isolates found at all locations were identified at the genus level: Chromobacterium sp., Pseudomonas sp., Bacillus sp., Micrococcus sp., Caulobacter sp., and Aspergillus sp. A correlation was observed between the number of PSMs and the level of soil P availability and moisture content, indicating an increase in soil P availability with a greater abundance of PSMs in soil.
磷（P）是植物生长的必需大量营养素，主要以农业土壤中不可用的形式存在。解磷微生物（PSM）增加了土壤中 P 的有效性。本研究的目的是评估 PSB 在马诺夸里农业土壤中的种群和类型及其与土壤特性的关系。在 Prafi 和 Masni 区的植物根际采集了 21 个复合土壤样本（0-20cm）。使用稀释技术和 Pikovskayas 琼脂培养基平板计数法检查了 PSM 种群、溶磷指数（PSI）和各种土壤特性。结果表明，溶磷细菌的总种群范围为 25×10 至 550×10 CFU g 土壤，而溶磷真菌的种群范围为 2.0×10 至 5.0×10 CFU g 土壤。分离株的 PSI 范围在 1.1 到 3.6mm 之间，其中芽孢杆菌（菌株 8）的效率最高，PSI 最高，假单胞菌（菌株 15）的效率最低。在所有地点发现的 6 个分离株在属水平上得到鉴定：Chromobacterium sp.、Pseudomonas sp.、Bacillus sp.、Micrococcus sp.、Caulobacter sp. 和 Aspergillus sp.。PSM 的数量与土壤 P 有效性和含水量之间存在相关性，表明土壤 P 有效性随土壤 PSM 丰度的增加而增加。
