Study on Exogenous Ethylene Induced Rice Resistance to Rhizoctonia solani

Rice sheath blight is one of the main diseases in rice production in China, which can make rice unable to absorb and utilize nutrients, and has a serious impact on rice yield and quality. In this study, exogenous ethylene was used to induce rice resistance against rice sheath blight, aiming at exploring a new environment-friendly control method of rice sheath blight. The results showed that within a range of certain concentrations, ethylene had no significant effects on mycelium growth, but it could induce resistance to sheath blight in rice. The optimum concentration was 0.2 mmol · L-1 and the relative control was 86.17％. It was found that ethylene could effectively increase the activities of peroxidase (POD), phenylalanine ammonia-lyase (PAL), β-1, 3-glucanase and reduce the contents of malondialdehyde (MDA), which could enhance the resistance of rice against Rhizoctonia solani. In addition, qRT-PCR detected the expressions of rice defense genes, which indicated that the expressions of the POX, PAL and OsPR1b genes were up-regulated.