Abstract

Potato is an important commercial crop of the world. It was reported to be affected by many biotic and abiotic factors. Among biotic factors is a blackleg, a bacterial disease of potato caused by Pectobacterium atrosepticum and is responsible for both quantitative and qualitative losses in the field and in the storage. This disease has been found to be more frequent in the districts of Chiniot. Therefore, a survey was conducted in field’s conditions of district Chiniot of Pakistan, as well as cold storages to assess the disease severity in the potato field. For isolation, samples were collected and identification, purification and mass culturing of the isolated of pathogen was also performed. The efficacy of different chemicals, plant extracts and bio-products were studied against isolated pathogen. During the screening trial of fifteen varieties, Cardinal was found immune while Faisalabad white was found to be highly susceptible. Other varieties like Accent, Harmony, Faisalabad Red and Lady Rosette were found resistant, while Desiree, SH70, Everest, Hermes, Orla and Paramount were found moderately resistant. Varietals response against this bacterium was evaluated under natural conditions in the field on weekly basis. Evaluation of different bio-products and plant extracts was carried out under laboratory conditions. Under the laboratory conditions, bio-products produced maximum inhibition zone. Plant extracts namely neem (Azadirachta indica), garlic (Allium sativum), datura (Datura alba) and onion (Allium sepa) also produced a little inhibition zone against the growth of Erwinia.

Key words: Potato, Pectobacterium atrosepticum, control, bio-products.