Effect of SA on prevention of powdery mildew in the greenhouse muskmelon

YAO Jun; GEN Xinli; ZHANG Cuihuan; ZAITUNA Maimaiti; ZHENG Heyun; LIAO Xinfu

doi:10.3969/j.issn.1673-2871.2017.10.009

Abstract：The growth of muskmelon in Xinjiang was influenced by kinds of diseases,especially powdery mildew.Considering the negative effects of the traditional insecticide on the environment,health of people and livestock,a new type biological pesticide (SA),which is a plant resistance inducer can stimulate plant defense system to achieve the effects of disease prevention.Different concentrations SA were used to treat the different stages (a week before flowering,10 days after male flower blossoming,and 10 days before harvest) in muskmelon plants.Changes of enzyme activity of PAL,PPO and POD of muskmelon leaves that were treated for 3 days,6 days and 9 days were determined,disease indexes after treated for 6 days were investigated,yield,fruit weight,soluble solids content,fruit hardness and Vitamin C content were measured after harvest.The results showed that the activity of PAL,PPO and POD were enhanced by SA,the effect of 100 μg· mL-1 SA was the best,with the increase of the treatment time,the activity of PPO and POD decreased firstly and increased subsequently,the activity of PAL exhibited a gradually decreasing process.The differences analysis had shown that the activity of POD reached significant level after treated for 6 days,and the activity of PAL and PPO reached significant level after treated for 3 days.According to the analysis of yield,fruit weight,soluble solids content,fruit hardness and Vitamin C content after harvest,the influences of powdery mildew upon the yield and quality of muskmelon were reduced effectively by 100 μg·mL-1 SA.