Encoding a Neutral Trehalase of Is Required for Growth and Virulence of the Pathogen.

is a soil-borne phytopathogenic fungus causing destructive Verticillium wilt disease. We previously found a trehalase-encoding gene () in being significantly up-regulated after sensing root exudates from a susceptible cotton variety. In this study, we characterized the function of in the growth and virulence of using its deletion-mutant strains. The deletion mutants () displayed slow colony expansion and mycelial growth, reduced conidial production and germination rate, and decreased mycelial penetration ability and virulence on cotton, but exhibited enhanced stress resistance, suggesting that is involved in the growth, pathogenesis, and stress resistance of . Host-induced silencing of in cotton reduced fungal biomass and enhanced cotton resistance against . Comparative transcriptome analysis between wild-type and mutant identified 1480 up-regulated and 1650 down-regulated genes in the strain. Several down-regulated genes encode plant cell wall-degrading enzymes required for full virulence of to cotton, and down-regulated genes related to carbon metabolism, DNA replication, and amino acid biosynthesis seemed to be responsible for the decreased growth of the strain. In contrast, up-regulation of several genes related to glycerophospholipid metabolism in the strain enhanced the stress resistance of the mutated strain.