Research On Chilling-resistance And Its Control In Eggplant (Solanum Melongena L.)

The research was first done on the chilling-resistance of eggplant at germination stage and seedling stage. The chemical regulating of chilling-resistance was also studied in detail. Then these physiological and biochemical indexes were analyzed. The main results were as follows.The chilling-germination of 28 cultivars was screened in this experiment. Three cultivars of the different chilling-resistance were selected according to germination percentage, germination viability, germination index and comprehensive index. High, medium and low chilling-resistant cultivars were Lanzhou-long-eggplant, Hebao-long-eggplant, Meiguo- red-eggplant 0The optimal testing temperature and appraisal indexes were 18 and germination index and comprehensive index through the low temperature testing at germination stage, respectively. At the seedling stage, the optimal test temperature,chilling-duration and physiological and biochemical appraisal indexes were 5, 24h and the activity of superoside dismutase (SOD), perosidase (POD), catalase (CAT), the content of malondialdehyde (MDA), the relative conductant rate, the content of protein (Pr) and proline (Pro), respectively. The relation between the chilling-resistance and these indexes was that the lower the relative conductant rate and MDA or the higher the activity of SOD, POD, CAT and the content of Pr and Pro, the higher the chilling-resistance would be. In addition, the comprehensive index was found to be more accurate to the appraising of chilling-resistance of eggplant than the single index.The application of CaCl2 could raise the activity of SOD, POD, CAT and the content of Pr. It decreased the content of MDA and the peroxidation of the membrane fat,so it increased the chilling-resistance. The concentration of 10mmol/L CaCl2 was suitable to enhance the chilling-resistance of eggplant.Salicylic acid (S A) could increase the activity of protective enzymes of cell membrane and decrease the content of MDA and Pr. Therefore, it increased the chilling-resistance of eggplant. In the range of the experimental concentrations, with the increasing of S A concentration, the effect of improving the chilling-resistance was more and more significant. The concentration of 7.5mmol/L SA was the best.