Abstract

Common rust incited by Puccinia sorghi Schw. is the most destructive fungal foliar disease of maize worldwide. It is reported that common rust diseases can greatly reduce grain yield of maize in susceptible genotypes by 40% on an average. Foliar disease management in maize often involves indiscriminate use of chemicals or total reliance on host plant resistance (HPR). Integrated disease management (IDM) have clearly demonstrated that when moderate levels of HPR are combined with field treatment and affordable levels of chemical control, expected yields and economic returns are higher than obtained with chemical control of susceptible genotypes. Local agronomic practices were followed during the same period of investigation. Foliar application of Tebuconazole @ 0.1% at 35 and 50 DAS, that is, T₁ was significantly superior and highly effective in reducing the disease severity (19.74%) and gave maximum grain yield (66.87 q/ha). The next best treatment was foliar application of Hexaconazole @ 0.1% at 35 and 50 DAS (28.23%) followed by foliar application of Tebuconazole @ 0.1% at 35 DAS and Neemazole F 5% at 50 DAS. The study suggests that any technology developed for maize should offer a clear yield and foliar disease resistance advantage over farmers’ current practices.

Key words: Botanicals, common rust, field evaluation, fungicides, integrated disease   management, Puccinia sorghi, Zea mays.