Bio-Control of Erwinia Soft Rot of Solanum Tuberosum in Pakistan : Evaluation of Plant Growth Promoting Rhizobacteria (PGPR)antagonistic Potential Against Potato Soft Rot Disease Pathogen

Potato (Solanum tuberosum L.) is an herbaceous, dicotyledonous, starchy, tuberous and annual vegetable crop. It is most cultivated vegetable crop of temperate and tropical and sub-tropical regions of the world. Potatoes stand fourth as world's most abundant food crop after rice, maize, and wheat.Potato soft rot caused by Erwinia carotovora has been reported to be most destructive and widely distributed disease. Samples were collected on basis of symptoms from different areas of Rawalpindi, Islamabad, Taxila and Gujranwala and the pathogen was isolated. Rhizobacteria were isolated from the rhizosphere of potato plant and evaluated for their ability to antagonize the rot pathogen in vitro using zone inhibition technique and by using whole potato assay along with pot experment. By inbibiton zone technique it was observed that out of 20 isolates, 3 isolates were efficient and had considerable antagonistic effect on the pathogen. Antagonistic rhizobacterial isolates were applied individually and in consortium and results revealed that treatments were effective variably while Best results were observed when isolates were applied in consortium as compare to individual isolates.