Studies Of Two Kinds Of Induced Reagent On Disease Resistance Of Cucumber

With the expanding of facility vegetable cultivation area,the corynespora leaf spot of cucumber is outbreak because of the low temperature,humidity and weak light in winter and spring seasons.There is no effective prevention and control measures.Biological induced reagents have the characteristics of compatibility with natural environment,purification of ecological environment and making pathogens resistant to insecticides,which can improve plant resistance to diseases and insect pests,reduce the use of pesticides and fertilizers,reduce environmental pollution,and promote the establishment of a virtuous cycle of vegetable production environment and sustainable agricultural development.Albit and Jingdusha are bioattractants used in production,but the control methods and mechanisms of the newly developed cucumber corynaria leaf spot are not clear.In this study,the best application techniques of Albit and Jingdusha were determined by pot inoculation,and the physiological and biochemical mechanism of their resistance to corynaria leaf spot were studied in order to provide theoretical basis for the application of production.The main results of this study were as follows:?1?The best application plans were as follows:Albit was used as 0.15 m L.L^-1,induced 2 times,5d interval,continuous 2d;and Jingdusha was used as 1.0mL.L^-1,induced 3 times,5d interval,continuous 5d..?2?After treatment with Albit,the plant height,stem diameter,root length and dry fresh weight of cucumber seedlings were increased,photosynthetic rate and soluble protein content were increased,but the intercellular CO₂ concentration,transpiration rate and soluble sugar content in leaves were decreased.The contents of soluble sugar and soluble protein increased after inoculated Corynespora cassiicola,the accumulation of O2^-·and H₂O₂ at 12h after inoculation,and the chlorophyll content of leaves increased at24h after inoculation.?3?After treatment with Jingdusha,the plant height,stem diameter,root length and dry fresh weight of cucumber seedlings were increased,the photosynthetic rate of leaves was increased,and the stomatal conductance and intercellular CO₂ concentration were increased at 12h after treatment.Leaf transpiration rate and chlorophyll content were increased at 24h,soluble protein content increased at 72-144 h,but soluble sugar content decreased.The contents of soluble sugar,soluble protein and chlorophyll in cucumber leaves were increased after inoculation of Corynespora cassiicola,and the content of O2^-·was accumulated at 12h.?4?Arbit and Jingdusha were directly induced the resistance of cucumber seedlings to corynespora leaf spot by increasing the contents of soluble sugar and soluble protein,and accumulation of O2^-·and H₂O₂.Meanwhile to increase the resistance indirectly by promoting the growth and development of cucumber plants and photosynthetic rate.