LAUSR

Abstract In this study, the (1→3)-β-D-glucan was isolated from yeast cell wall for investigating its effect on reducing the postharvest decay of pear fruit caused by Penicillium expansum and the underlying mechanisms. The results demonstrated that (1→3)-β-D-glucan could significantly induce disease resistance against P. expansum in pear wounds. (1→3)-β-D-glucan did not directly affect the growth of P. expansum in vitro and in vivo, whereas the spore germination of the pathogen was obviously inhibited in pear wounds when the induction time increased to 24 h by (1→3)-β-D-glucan. Furthermore, a large variety of defense-related genes, including PR1, GLU, endoGLU9, CHI4, endoCHI, PR4, PR5, CHI3 and PAL, were markedly up-regulated by (1→3)-β-D-glucan treatment. To the best of our knowledge, this is the first report that (1→3)-β-D-glucan can induce the disease resistance in the postharvest fruit. These findings suggest that application of (1→3)-β-D-glucan may be an effective strategy to reduce the fungal rot of the postharvest fruit.