Effect of Oxathiapiproline-Famoxadone fungicide and Trichoderma sp. on Control of Downy Mildew and the Growth of Maize

Downy mildew caused by Peronosclerospora spp. is a major limiting factor in maize production in Indonesia. Susceptible varieties can have yield losses of around 90 to 100%. The continuous use of metalaxyl has triggered resistance to downy mildew. Therefore, it is necessary to have other fungicides that can replace the use of metalaxyl. In this study, the oxathiapiproline- famoxadone was tested in combination with the fungus Trichoderma sp. as an alternative to metalaxyl. This study used a randomized complete block design. The treatments were arranged in a factorial with 2 factors. The first factor was fungicide (without/F0 and with fungicide/F1). The second factor was Trichoderma sp., i.e. T0 (without Trichoderma sp), T1 (Trichoderma sp. 106 spores/ml), T2 (Trichoderma sp. 107 spores/ ml), and T3 (Trichoderma sp. 108 spores/ml). The results showed that oxathiapiproline-famoxadone was able to suppress downy mildew, while the application of Trichoderma sp. did not affect the control of downy mildew and maize plant growth. Fungicide application and Trichoderma sp. 107 spores/ml suppressed disease severity at 7 days after inoculation with Peronosclerospora sp.