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Strain An-F was isolated from the rhizosphere soil of replant site of apple orchard at Shimla district H.P. and identiûed as Pseudomonas aeruginosa on the basis of biochemical tests and by 16S rRNA sequences. This bacterium exhibits a broad-spectrum antifungal activity towards phytopathogenic fungi. The antifungal metabolite by An-F was extracted and characterized using TLC and HPLC (High pressure liquid chromatography). Production of siderophores, phosphatase, HCN, ammonia, indole-3-acetic acid (IAA), gibberellins and cytokinins in An-F were determined. The antifungal metabolite produced by An-F has been identiûed as 2, 4-diacetylphloroglucinol on the basis of TLC and HPLC data. Present study reports the production of 2,4-diacetylphloroglucinol as well as IAA, gibberellins and cytokinins for the ûrst time by a saprophytic P. aeruginosa strain An-F isolated from the replant site of apple. Because of the production of siderophore, growth hormone, protease and phosphatase and its innate fungicidal potential, this strain can be used as biofertilizer and antagonist against a range of phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Molecular markers have been found useful in assessing the genetic diversity in a precise manner, which is based on naturally occurring DNA polymorphism. Random Amplified Polymorphic DNA analysis was performed using four arbitary decamer primers to observe genetic homogeneity/ polymorphism among 10 isolates of fluorescent Pseudomonas spp. isolated from apple and pear rhizosphere from different locations of Mandi and Chamba districts. Out of 52 bands generated with 4 RAPD primers, 13.46% were monomorphic bands, while 86.33% were polymorphic bands. The result showed that the isolates of fluorescent Pseudomonas sp. were divided into 2 clusters by RAPD primers. Among all the combinations maximum similarity (90.48%) was found between PN-7-Cha and PN-2-San isolates of Chamba and Mandi districts. However, minimum similarity (36.7%) was observed in PN-11-San and PN- 7-Cha isolates of Mandi and Chamba districts. This technique is highly beneficial for testing similarity analysis among fluorescent Pseudomonas spp. isolated from different locations. [ABSTRACT FROM AUTHOR]