Fig. 6

Proposed model for the role of γ-PGA in maize under long-term drought. γ-PGA can improve the drought resistance of maize by regulating the expression of ABA biosynthesis-related genes, ABA signal transduction-related genes, photosynthesis-related genes and other stress-responsive genes (osmotic protection, stress response and protein folding genes) and enriching plant-promoting bacteria such as Actinobacteria, Chloroflexi, Firmicutes, Alphaproteobacteria and Deltaproteobacteria. In addition, the ABA content and urease activity in maize rhizosphere soil also increased