Department of Microbiology, Acharya Nagarjuna University, Nagarjuna Nagar, 522 510 Andhra Pradesh, India.
Indian J Microbiol. 2009 Mar;49(1):98-102. doi: 10.1007/s12088-009-0005-1. Epub 2009 Apr 21.
Forty-six Rhizobium isolates from legume root and stem nodules were examined for their phosphate-solubilizing ability on Pikovskaya's agar medium. Rhizobium isolates from root nodules of Cassia absus, Vigna trilobata and three strains from Sesbania sesban showed zone of tricalcium phosphate (TCP) solubilization. The isolate from C. absus showed maximum solubilization (620 μg/ml) after 12 d of incubation, while the Rhizobium sp. strain 26 (from S. sesban) showed the least amount (150 μg/ml) of phosphate solubilization. Among the carbon sources tested for their ability to solubilize TCP, maximum solubilization (620 μg/ml) was observed in glucose by Rhizobium isolate from C. absus. Phosphate solubilization increased with increase in glucose concentration steeply up to 2% and slowly above this concentration in four isolates. Among the nitrogen sources tested, maximum solubilization (620 μg/ml) was observed in ammonium sulphate by Rhizobium isolate from C. absus.
从豆科植物的根和茎结瘤中分离得到 46 株根瘤菌，在 Pikovskaya 琼脂培养基上检测其溶磷能力。从Cassia absus、Vigna trilobata 的根瘤中分离到的根瘤菌以及来自 Sesbania sesban 的 3 株菌株显示出了磷酸三钙（TCP）的溶磷区。培养 12 天后，从 C. absus 分离得到的菌株显示出最大的溶磷量（620μg/ml），而 Rhizobium sp. 菌株 26（来自 S. sesban）显示出最少的溶磷量（150μg/ml）。在测试的碳源中，C. absus 分离得到的根瘤菌在葡萄糖中表现出最大的 TCP 溶磷能力（620μg/ml）。溶磷量随着葡萄糖浓度的增加而急剧增加，在 4 株菌中最高可达 2%，然后在这一浓度以上缓慢增加。在测试的氮源中，C. absus 分离得到的根瘤菌在硫酸铵中表现出最大的溶磷能力（620μg/ml）。
