Management of the Black Mould Disease of Onion

Samples of onion seeds were collected from farmer’s houses to manage the seed mycoflora of onion through fungicides, plant extracts and bioagent seed treatments. Amongst fungicides used as seed treatment, in vitro Bavistin (Carbendazim 50% WP, 2.0%) proved to be most effective against Aspergillus niger followed by Thiram (80% WP, 2.5%), Captan (50% WP, 2.5%), Indofil M-45 (50% WP, 2.5%) and Topsin M (75% WP, 2.5%) in improving seed germination and vigour index, by reducing pre- and post emergence mortality and number of seedlings showing symptoms. Similarly, among bioagents and plant leaf extract used, Trichoderma viride (5.0 ml (108 cfu/ml)/10 g seeds) followed by Trichoderma pseudokoningii (5.0 ml (108 cfu/ml)/10 g seeds) and Safeda (5.0 ml/10 g seeds) followed by neem leaf extracts (5.0 ml/10 g seeds) proved to be effective in improving seed germination and vigour index, by reducing pre- and post emergence mortality and number of seedlings showing symptoms