Antagonistic interactions between maize seeds microbiome species and the late wilt disease agent, .

is a maize pathogen that causes severe damage to commercial corn fields in the late growth stages. Late wilt disease (LWD) has spread since its discovery in the 1960s in Egypt and is now reported in about 10 countries. The pathogen has a hidden endophytic lifecycle in resistant corn plants and secondary hosts such as green foxtail, watermelon lupin and cotton. At the same time, it could be an opportunist and hinder the host development under the right conditions. This study uncovered interactions with newly identified maize endophytes. To this end, six fungi were isolated from the seeds of three sweet corn cultivars having varying susceptibility to LWD. These isolates were identified using colony morphology and microscopic characterization, universal internal transcribed spacer (ITS) molecular targeting and phylogenetic analysis. Most of them belonged to pathogenic species. Compared to three previously identified bioprotective microorganisms, the new species were tested for their ability to secrete metabolites that repress and to antagonize it in a solid media confront test and a seedlings pathogenicity assay. The opportunistic fungal species (ME1), (PE3) and the reference biocontrol bacteria (R2) achieved the highest inhibition degree in the plates tests (74-100% inhibition). The seedlings' pathogenicity assay that predicts the seeds' microflora resistance to highlighted the bio-shielding potential of most species (23% or more epicotyl elongation over the infected control) sp. (ME2) was the leading species in this measure (43% enhancement), and gave the best protection in terms of seeds' germination (50%) and sprouts' biomass (34%). The results of this study could enhance our understanding of the pathobiome's role in the context of LWD and represent a first step in using the seeds' natural protective microflora to develop novel management strategies.