Studies on Basal Bulb Rot of Onion Caused by fusarium Oxysporum F.sp. cepae

Basal bulb rot of onion causes considerable damage. In recent years Fusarium basal rot of onion has assumed a serious problem and hence the studies were undertaken on this disease with the objectives viz., isolation of the causal organism, its identification, pathogenicity, morphological and cultural characters. The causal organism was isolated from infected bulbs of onion. The pathogenicity of onion basal bulb rot pathogen was proved by soil inoculation method. The fungus culture was identical as Fusarium oxysporum f.sp. cepae. on the basis of morphological characters of the pathogen. Among the various cultural media used an, excellent mycelial growth and sporulation were observed on PDA, Richards agar and were followed by Czapeck's dox agar, host leaf extract, coon's agar and A. and H. medium.