Effects Of High Temperature Stress Responses Under CO₂ Enrichment Of Greenhouse Eggplant

This experiment take eggplant as test material, and the changes of CO2 concentration and temperature simulated in the experiment, study of the effect on photosynthesis, making use of nitrogen, protective enzyme activity, osmotic accumulation and microstructure under the conduction of elevated atmospheric CO2, high temperature and both of them. The main results were as follows:1,The eggplant still maintain the high photosynthesis rate and the content of chlorophyll under the treatment of elevated CO2, and the highest photosynthetic rate is higher than CK under the treatment of high temperature and elevated CO2. The results indicate that elevated CO2 could enrich the content of chlorophyll and speed the growth of eggplant.2,The ability of absorption of nitrogen is decreased under elevated CO2, and the activity of nitrate reductase also decreased, but the absorption of nitrogen were promoted and nitrate reductase increased earlier and decreased later under high temperature. The content of nitrogen was decreased and the change of nitrate reductase was unobvious under complex stress.3,The activity of protective enzymes (SOD,POD,CAT) and the content of non-enzymatic antioxidants (ASA and GSH) were increased under the treatment of elevated CO2, and the content of MDA and relative conductivity were decreased along with the processing time, the content of Proline, soluble protein and HSP were increased, the production rate of superoxide anion was slower, so the increase of protective enzymes can clean up the accumulate of overdose active oxygen, thereby it can keeping normal growing development and reduce the damage of the accumulation of overdose active oxygen. However, the damage caused by high temperature was relief under complex stress, it showed that the activity of protective enzymes and the content of non-enzymatic antioxidants were increased, but the effect did not significantly than the treatment of elevated CO2.4,The mainly effect on leaf were incrassation of palisade parenchyma, the dyeing of starch grain were deepen. The effect was aggravated under complex stress. The effect of high temperature on palisade parenchyma and spongy parenchyma were arrange loose, and there had some irregular lipidic sphere, plasmolysis was serious in spongy parenchyma.