MANGROVES M. MASILAMANI SELVAM1 AND K. KATHIRESAN
Abstract
A study was made on the rhizosphere-residing bacterial strains of azotobacters and phosphatesolubilizing bacteria from the soil around the roots of two mangrove zones (Rhizophora and Avicennia). Besides microbes, the levels of available nitrogen, available phosphorus, potassium and total organic carbon were also analyzed in the rhizosphere soil samples at a monthly interval for one year. The counts of azotobacters were higher in the rhizosphere of Avicennia than Rhizophora. A reverse of this trend was found with the counts of phosphate-solubilizing bacteria. Besides nitrogen-fixing azotobacters, the levels of N and P were significantly higher in the Avicennia zone than in the Rhizophora zone, but not the levels of K and total organic carbon.