Field application of beneficial microbes to ameliorate drought stress in maize

Abstract

Background and aims: Drought stress is a challenge to maize (Zea mays L.) production, especially in an era of unpredictable climate change and weather extremes. Maize is a source of calories for millions of people all over the world. It is a food security crop, and any yield loss has food security implications. This study examines the effects of soil microbes on maize growth and yield under drought conditions, focusing on field-based experiments. Methods: This review follows PRISMA guidelines to systematically evaluate studies on the field effects of soil microbes on maize growth and yield under drought stress. A comprehensive search across multiple scientific databases using specific keywords and Boolean operators identified 78 manuscripts published between 2010 and 2024. After applying inclusion and exclusion criteria, only 9 studies met the criteria for microbial application in maize fields under drought conditions. Results: Microbial Biofertilizer applications enhance maize performance compared to uninoculated plants. Complementary application of biofertilizer together with conventional fertilizers outperforms sole application of biofertilizer in ameliorating drought stress in maize under field conditions. This study highlights some mechanisms through which soil microbes contribute to drought tolerance, the influence of environmental factors and host plant characteristics on microbial inoculants' effectiveness. Conclusions: The diverse array of growth-promoting microbial species available and their application methods offer significant potential for improving agricultural resilience. By integrating microbial technologies into farming practices, the challenges posed by climate change to food security may be reduced, thus contributing to sustainable agricultural production.