Seed Priming with Desert Microalgal Biomass Enhances Vigor and Early Growth of Maize (Zea mays L.)

Desert ecosystems harbor microbial communities adapted to extreme environmental conditions, including water scarcity, elevated temperatures, and intense UV radiation. Among these microorganisms, microalgae represent promising resources for agricultural applications. In this study, microalgae isolated from desert soils in Mexico were characterized by molecular (rbcL) and phylogenetic analysis, and morphological observations. They were identified as Chlorella sp. (RAD3), Nannochloris-related isolate (RAD4), and Chlorella cf. variabilis (RAD5). The effects of microalgal biomass on maize (Zea mays L.) germination and early seedling development were evaluated using a seed-priming approach. Microalgal treatments significantly improved (p < 0.05) germination-related traits, seedling vigor, shoot height, root length, and fresh and dry biomass, as compared with the control. Chlorella cf. variabilis (RAD5) was associated with reduced germination time, whereas Nannochloris-related isolate (RAD4) consistently produced the strongest responses in vigor and growth parameters. Although some variables reached their highest numerical values at 108 cells/mL, similar responses were usually observed at 107 cells/mL. Overall, the evaluated desert-derived microalgal preparations were associated with improved early maize seedling performance, under the evaluated conditions.