Investigation of Pea (Pisum sativum L.) Seed Mycoflora and its Control

Abstract

The study aims to isolate the seed mycoflora of Pea (Pisum sativum L.) and control the pathogens. Seed sample of pea were collected from local markets of Kathmandu valley and randomly mixed. Three standard methods recommended by the International Seed Testing Association, 1950 were performed, viz. the standard blotter technique, the agar plate method and the moist sand method. Total 11 fungal pathogens were isolated by all the three methods. The agar plate method was comparatively the most suitable method for the isolation purpose because large number of fungal species was isolated adopting this method. Aspergillus clavatus, Penicillium sp., Rhizopus sp., Cladosporium sp. etc. were isolated only in unsterilized seed so they are labelled as surface contaminants. Rest of the species like Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Fusarium sp. were proved as truly seed borne species because they are found in both sterilized and unsterilized seeds.

Effect of some fungicides like Bavistin, Derosal and Dithane M-45 against the control of test pathogens, Aspergillus niger and Aspergillus flavus were studied by the sand and the thread method. The sand method showed Derosal was effective in controlling Aspergillus niger while Bavistin was effective in controlling Aspergillus flavus. In thread method, Bavistin and Derosal prevented the growth of pathogens. In conclusion, Derosal was found most effective against both test pathogens.