Butanediol induces brown blotch (Rhizoctonia solani) resistance in creeping bentgrass by enhancing the anti-oxidation of reactive oxygen species and sucrose metabolism

There is evidence that 2,3-butanediol (2,3-BD) can increase resistance to plant diseases via the induced systemic resistance (ISR) pathway. Brown blotch is caused by Rhizoctonia solani and is regarded as among the foremost diseases of Agrostis lawns. We sought to explore the effects of 2,3-BD treatments on the antioxidant metabolism and sucrose metabolism in brown blotch disease of creeping bentgrass ( Agrostis stolonifera cv. Penn A4). The results showed that when exogenous 2,3-BD was applied by soil injection before creeping bentgrass seedlings were inoculated with Rhizoctonia solani for nine days, such pretreatment could effectively reduce the disease index of turf brown blotch. However, we reported reduced accumulation of reactive oxygen species (ROS), including the H 2 O 2 content and O 2 •− generation rate, the OH • concentration, lipoxygenase activity, and the malondialdehyde content following pathogen infection. 2,3-BD induction amplified the activities of antioxidant enzymes (catalase, superoxide dismutase, catalase, glutathione peroxidase, and ascorbate peroxidase) while simultaneously increasing glutathione and ascorbate contents. These responses are approaches to scavenge ROS associated with pathogen infection. The pathogen also triggers a change in sugar contents and defense reactions in plants (including the redistribution of plant sugars). Of note, 2,3-BD pretreatment can regulate sucrose synthase-synthesis and sucrose synthase-cleavage and regulate the activity of sucrose phosphate synthase and sucrose phosphate phosphatase in plant sucrose metabolism. These events contribute to significant changes in the soluble sugar components and reduce the loss of sucrose. Collectively, these data strongly suggest that 2,3-BD can induce both antioxidant metabolism and sucrose metabolism in creeping bentgrass, thereby increasing its resistance to brown blotch ( Rhizoctonia solani ).