Arbuscular mycorrhizal fungi enhance drought resistance in by regulating SOD family genes.

The physiological activity facilitated by arbuscular mycorrhizal fungi (AMF) contributes to plants' ability to tolerate drought. Nevertheless, it is unclear if AMF colonization affects the expression of genes in the host plant that encode antioxidant enzymes in the superoxide dismutase (SOD) family, which help alleviate drought stress in plants. Here, we conducted a pot trial to determine whether colonization by the AMF improves drought resistance in . We comprehensively analyzed the gene family and evaluated genome-wide expression patterns of and SOD activity in AMF-colonized and non-mycorrhizal plants under simulated drought. We identified a total of 13 SODs in the genome of , including three (), three (), and seven (). Phylogenetic analysis based on binding domain revealed that genes from and various other plant species can be divided into three separate groups, showing significant bootstrap values. Our examination of gene composition and patterns suggests that most genes in these three subgroups are significantly conserved. Additionally, it was noted that hormones and stress-responsive cis-regulatory elements were found in all promoters. Expression profiling by qRT-PCR demonstrated that AMF increased relative expression levels of in both roots and shoots under drought stress, except for in roots. Furthermore, AMF colonization increased the relative expression of and in roots, augmenting SOD activities and increasing ROS scavenging during drought. In general, this work offers molecular evidence in support of the beneficial effect of AMF colonization on drought tolerance in . It also elucidates the expression patterns of genes, which will support efforts to optimize mycorrhizal seedling cultivation under stressful conditions.