Induction of Maize Resistance to Downy Mildew Disease Peronosclerospora Spp. Using an Endophytic Consortium

Maize resistance to downy mildew is connected with the activation of multiple defense responses that slow or stop infection at specific stages of the host-pathogen interaction. The interaction between the pathogen and the host plant induces several changes in cell metabolism, especially phenolic content, activity of peroxidase enzyme (POD), and salicylic acid. In this study, an analysis was carried out on the effect of a consortium of endophytic microbes from the fungal group (isolates of AC-1, AC-2, AC-3, and DC-5) and bacterial group (isolates of II-D1, IV-B2, I-A1, III-A2, and I-D3) to control downy mildew in maize through seed treatment and watering of the isolate suspension around plant roots at 14 days after planting under screen house conditions. The results showed that DC[1]5+II-D1endophytic consortium significantly suppressed downy mildew disease up to 71 %, with the total phenolic content after inoculation 10.3 ppm. In comparison, the DC-5+I-A1 endophytic consortium treatment recorded the highest increase in salicylic acid concentration of 330 %. This treatment did not significantly affect the peroxidase enzyme activity. This study contributes to the understanding of potential mechanisms involved in the defense of maize against downy mildew, highlighting the role of POD and salicylic acid in plant susceptibility to pathogens.