Evaluation of fungicides against angular leaf spot of French bean caused by Phaeoisariopsis griseola

Angular leaf spot of bean caused by Phaeoisariopsis griseola is a serious foliar disease of French bean in northern India. The relative efficacies of different fungicides including six systemic and nonsystemic fungicides and four combi-products were evaluated against P griseola under in vitro and in vivo conditions. The in vitro evaluation studies indicated that fenamidone (10%) + mancozeb (50%) (Sectin WG), pyraclostrobin (5%) + metiram (55%) (Cabrio Top WG), azoxystrobin (20%) + difenoconazole (12.5%) (Amistar Top SC), trifloxystrobin (25%) + tebuconazole (50%) (Nativo WG) and azoxystrobin (25%) (Amistar SC) alone were potent growth inhibitors of P griseola. Field evaluation for two consecutive years (2011 and 2012) revealed that four periodic sprays of Sectin at 15 days interval were most effective in controlling the disease and enhancing the green pod yield.