Effect Of High Temperature And CO₂ Enrichment On Microstructure And Physiological Basis Of Cucumber In Greenhouse

Taking Jin Chun No.4 cucumber as test materials, Microstructure of cucumber leave,stem and root tip and content of starch and soluble sugar were studied in order to ascertain the effect of high temperature and CO₂ enrichment on microstructure and physiological basis of cucumber in greenhouse. The main results are as follows:1. The Microstructure of leaves of cucumber with high temperature and CO₂ enrichment were investigated. It showed that, the thickness of epidermis, palisade tissue and leaf increased simultaneously in CO₂ enriched leaves, and the ratio of palisade tissue to spongy tissue went up slightly. The number of palisade cells and spongy cells increased as a result of CO₂ enrichment . Both longer and more tightly arranged palisade cells were observed in leaves with CO₂ enrichment . The length of lower epidermis cell increased obviously in CO₂ enriched leaves, but the degrees increased in width of lower epidermis cell is different at different treatments.2. The number of epidermal cells and stomal increased, at the same time leaf area increased significantly, But leaf area of T2 and T3 was less than leaf area of CK and T1.3. The starch grain of leaf and root tip increased at the high temperature and CO₂ enrichment conditions, but it was less than the starch grain of CK and T1 .The change of starch content was the same.4. CO₂ enrichment made the pigment content of leaves of cucumber increased , compared with the leaves in high temperature situation chlorophyll added obviously.5. The photosynthetic rate of leaf of greenhouse cucumber with CO₂ enrichment was higher than that of the condition of high temperature. It showed that, the cucumber still maintain higher photosynthesis rate under high temperature and CO₂ enrichment.