Comparative Effect of Pseudomonas aeruginosa, Pseudomonas fluorescens and Pseudomonas putida on the Growth of Replanted Apple

Fluorescent Pseudomonas species have a number of traits like antifungal, siderophores, phosphate solubilization, lytic enzymes, HCN, ammonia and plant growth regulators that allow them to act as plant growth promoting and biocontrol agents. They competitively colonize plant roots, play important role in enhancing the growth of plants and in plant disease control. These may be used for soil improvement and to increase soil fertility hence for management of replant problem of apple in Himachal Pradesh. To ensure the sustained availability of PGP and biocontrol agent’s in soil formulation development protocol has to be standardized. On the basis of different PGPR activities three indigenous strains viz., Pseudomonas aeruginosa C, Pseudomonas fluorescens M and Pseudomonas putida L were selected for field studies. In all the treatments with individual (L, M and C) and consortia strains (L+M, L+C, M+C, L+M+C) there was an 8.0 to 86.5 per cent increase in plant height as compared to control. The performance of replanted apple was much better in terms of root colonization capacity, plant establishment and increase in plant growth in terms of plant height, number of nodes and branches over their respective control after fifteen months of plantation.