Maize-associated Meyerozyma from the Brazilian semiarid region are effective plant growth-promoting yeasts

Yeasts are potential plant-growth-promoting microbes; however, this resource is underexploited, mainly in the semiarid regions worldwide. In the present study, we isolated potentially endophytic yeasts from roots of field-grown maize and characterized them at molecular, biochemical, and associative levels. Thirteen yeasts were retrieved, and the ITS1-5.8 S-ITS2 region sequences identified them within the Meyerozyma genus. The phylogenetic analyses showed that 12 out of 13 strains were closely related to M. guilliermondii CBS 2030T and ESA 35 to M. caribbica CBS 9966T. All yeasts synthesized indolic compounds and were favorable for siderophore production, and eleven proteolytic and seven amylolytic Mayerozyma spp. were identified. The principal component analysis positively correlated the in vitro characteristics and the maize growth promotion, highlighting six promising strains. Our results indicated that the maize-associated yeasts from the genus Meyerozyma are potential tools for inoculant production for plant growth promotion.