A Green Solution to Maize Late Wilt Disease

Late wilt disease of maize, caused by Magnaporthiopsis maydis, is considered a major threat to commercial fields in Israel, Egypt and other countries. Today’s control methods include chemical and agronomical intervention, but they rely almost solely on resistant maize cultivars. Global disease research is focusing on eco-friendly biological approaches to restrain the pathogen. To this end, we tested nine isolates of Trichoderma spp. known for their high mycoparasitic potential as biocontrol agents against M. maydis in the lab. High-potential biocontrol agents were selected and evaluated in growth room sprouts, in full-season greenhouse plants and in a commercial field. In addition, we isolated and identified the Trichoderma asperellum-secreted metabolite, 6-pentyl-α-pyrone, exhibiting strong M. maydis antifungal activity. This pure ingredient was tested against the pathogen in plants over a full growth period. Finally, manipulating the plant’s endophytes and soil mycorrhiza (by selected crops in rotation with maize and minimal tillage) has a high potential to reduce late wilt disease. The results of these studies suggest a biological-based protective approach that may have significant value in late wilt integrated prevention.