High Temperature And High CO₂Concentration Response Mechanism Of Grafting Cucumber In Greenhouse

By using the seed pumpkin root stock and "tianjin spring4" cucumber varieties JiaJieMiao as test materials, through the high temperature, high concentration of CO2greenhouse grafting cucumber growth, photosynthetic characteristics, photosynthesis product, Rubisco carboxylase (Rubisco) activity, enzyme defense system and grafting yield and quality of cucumber, draw the following conclusion:(1) the cucumber greenhouse grafting through high temperature and increased CO2concentration; processing, make the photosynthetic available radiation, the intercellular CO2concentrations, and stomatal conductance and YeWen improve, transpiration rate, chlorophyll content increases, starch synthesis increase, starch convert sugar increase, to make the cucumber greenhouse grafting the increase plant height, leaf area and photosynthesis of leaf thickness increase.(2) greenhouse grafting through high temperature and the cucumber was CO2concentration processing, make the Rubisco carboxylase (Rubisco) activity improved, so as to increase the CO2fixation; Grafting cucumbers plasma membrane permeability, Pro, MDA content are below normal management, enzyme defense system (of SOD and POD and CAT) activities were higher than normal management. Effectively weaken the high temperature on grafting cucumber seedlings leaves the damage caused, improve the cucumber plant defense of high temperature grafting ability, to the greenhouse grafting cucumber heat resistance has stimulative effect. From the above two aspects show that high temperature, high CO2concentration decreases in greenhouse grafting of cucumber in photosynthetic "nap" phenomenon, improve the cucumber greenhouse grafting yield and quality.