Effect of microalgae and bacillus on purple blotch (Alternaria porri) of onion (Allium cepa L.)

Onion (Allium cepa L.) is a biennial bulb crop, produced all over the world. It is attacked by many diseases, out of which Purple blotch of onion caused by Alternaria porri (Ellis) Neerg causing heavy yield loss in both bulb production and seed production. Native Bacillus were isolated from the rhizosphere of vegetables and ornamental crops of the SHUATS campus and were identified through bio-chemical tests.