Physiological studies on grafted plants of fruit vegetables

嫁接技术在果菜生产中被广泛接受，以避免土传病害或增强抗寒性。但在商业种植中，嫁接苗由于砧木植株吸收水分和矿质营养的能力强，因而生长旺盛。在弱光条件下，黄瓜嫁接体的干物质积累明显滞后于Shintosa（C.moschata × C.maxima）。嫁接植株在弱光下生长时，叶片组织中的氮含量高于非嫁接植株。新土佐上黄瓜叶片中NH_4-N和Mg含量较高。结果表明，在低温条件下，无花果嫁接黄瓜植株生长优于新土佐嫁接黄瓜，在高温条件下，新土佐嫁接黄瓜植株生长势强，叶片中NH_4-N和Mg含量显著高于无花果嫁接黄瓜，在低温条件下，嫁接黄瓜的光合速率、叶片中Mg含量、叶片中NH_4-N含量、叶片中Mg含量嫁接黄瓜对环境条件的反应主要取决于砧木植株的生理特性，不仅表现在水分和矿质营养的吸收上，而且在光合作用、转运和蒸腾作用中也起作用。

Grafting has been widely accepted in growing fruit vegetables in order to avoid the soil-born diseases or to encourage the chilling resistance. In the commercial growing, grafted plants, however, used to grow so vigorously as a result of higher ability of water and mineral nutrient uptakes of rootstock plant. The present studies were undertaken to elucidate the physiological characteristics of grafted plants when exposed to some different environmental conditions.Under lower light condition, cucumber plants grafted on C.ficifolia showed significant retardation in dry weight accumulation as compared with the plants on Shintosa( C.moschata x C.maxima ). Grafted plants contained more nitrogen in leaf tissue than in non-grafted plants when grown under low light. Cucumber plants on Shintosa had higher NH_4-N and Mg concentration in the leaf. Plants grafted on C.ficifolia showed superior growth under low temperature, and inferior growth under high temperature to the plants on Shintosa.Under higher light condition, cucumber plants grafted on Shintosa grew more vigorous, NH_4-N and Mg concentration in the leaf being considerably higher than the plants on C.ficifolia.Under lower temperatures, photosynthetic rate, translocation rate of assimilates and transpiration rate were higher in the plants on C.ficifolia.Grafted cucumber responded markedly to the environmental conditions exposed depending greatly on the physiological characteristics of rootstock plant, not only in water and mineral nutrient uptakes, but also in photosynthesis, translocation and transpiration.