Effect of ethylicin on prevention and control of sugarcane leaf scald and its promoting effect on growth
In order to explore whether the biomimetic and endogenous chemical agent ethylicin can be used to prevent and control sugarcane disease and whether it can promote the growth of sugarcane,the in-door antibacterial tests,toxicity tests,and barrel planting application tests were carried out to evaluate the prevention and control effect of ethylicin on sugarcane leaf scald caused by Xanthomonas albilineans(Ash-by)Dawson.At the same time,the agronomic traits,biomass,and other phenotypes of sugarcane treated with different concentrations of ethylicin were determined by pot planting experiments,and the growth pro-moting effects were evaluated by combining the physiological characteristics such as photosynthesis,root system,and stress resistance.The results of toxicity test showed that the toxicity regression equation of ethylicin was y=26.29x-30.29,the correlation coefficient R2 was 0.948 9,and the effective middle mass concentration EC50 was 1 132.43 μg/mL.The results of disease prevention and control and growth promo-tion experiments showed that the 1 000-fold dilution of 80%ethylicin was the best.Under this treatment,no sugarcane leaf scald positive plant was detected after 42 days of application,while the positive rate of the control(CK)was 100%.Moreover,compared with CK,the chlorophyll content in sugarcane leaves increased by 24.93%,the net photosynthetic rate increased by 64.97%,and the root activity increased by 62.44%,indicating a significant growth promoting effect.In addition,compared with CK,the antioxidant enzyme activities such as SOD,POD,and CAT under this treatment increased by 21.32%,44.32%,and 54.32%respectively.The content of soluble sugar,soluble protein,proline and other osmotic regulating substances in leaves increased by 17.40%,17.39%,and 17.78%,respectively,while the content of MDA decreased by 22.74%,alleviating membrane lipid peroxidation,maintaining cell membrane stability and enhancing the stress resistance of sugarcane.In summary,the 1 000-fold dilution of 80%ethylicin has a good control effect on sugarcane leaf scald and has a promoting effect on sugarcane growth.