Triadimefon increases drought tolerance through the regulation of photosynthesis and carbohydrate metabolism in rapeseed at bolting stage

Drought is a major abiotic factor limiting agricultural crop production. The focus of this study was the effect of triadimefon (TDM) on rapeseed photosynthesis and carbohydrate metabolism in response to drought stress. Results showed that TDM increased plant dry mass per plant and reduced the damage to photosynthetic processes by regulating stomatal and nonstomatal factors, inducing photosynthetic pigment synthesis, and improving photosynthetic activity. Chloroplast degradation and senescence was reduced in rapeseed leaves with TDM under drought stress. TDM restored structural connections between chloroplasts and cell membranes and modified the chloroplasts - from slightly elongated ellipses to archetypical ellipses. TDM also regulated enzymatic activity of sugar metabolism. These results indicate that TDM improved drought tolerance through the regulation of photosynthesis and carbohydrate metabolic pathways in rapeseed at the bolting stage, thereby increasing biomass under drought stress.