| Eggplant (Solatium melongena L.) originated in southeast Asia and Indian, which had been cultivated for a long time in China. As it grows in warm climrte, it is usually subject to chilling and cold damage. With the increase in cultivated areas of protective cultivation year after year, eggplant cultivars resistant to chilling are badly need, but breeding materials with chilling resistance have to be provided for obtaining. Likewise, screening breading materials for chilling resistance need chilling resistance indices correspondly. Owing to the strict region of eggplant, the studies of eggplant chilling resistance were less advanced than tomato and pepper. So using simple, fast and correct methods and indices of chilling resistance can enhance the efficiency of identifying and screening materials and cultivars.Eight different biochemical and physiological indices of chilling resistance and their correlations were studied using eight different eggplant cultivars, as a result of which three simple, fast and useful indices had been screened, chilling resistance of which thirty-four eggplant materials was then used to investigate. The main results were as follows:1. Effect of different temperature on seed germination was studied. The chilling resistance appraisal of eggplant seed could be used germination index and hypocotyls length at 18 , but the vigor index at 18掳C was more correct and reliable, whereas germination percentage could not be used to identify chilling resistance of seed.2. From the chilling index of controlled low temperature conditions, significant negative correlation was observed between chilling index and chilling resistance of cultivars, and there was different in different cultivars. As the method was simple and easy to operate, the method could be used to fast method of appraising chilling resistance of eggplant at seedlings stage.3. Electric conductivity percentage of eggplant leaves was determined using electric conductivity. Significant negative correlation was observedbetween chilling resistance and electric conductivity percentage, and the difference was obvious among them. So the electric conductivity percentage at 5 could appraise the chilling resistance of eggplant at seedlings stage.4. The effect of different low temperatures on soluble sugar content of eggplant seedlings was studied, significant positive correlation was observed between the content of soluble sugar and chilling resistance of cultivars, and there was certain different among them. The content of soluble sugar in the cultivars more resistant to chilling was higher than the less ones. The effect was not obvious to induce the soluble sugar at 15 . So the chilling resistance of cultivars could be represented by the content of soluble sugar in eggplant leaves at 5 .5. The effect of different low temperatures on the content of Pro in eggplant seedlings was studied. There was different Pro content in different eggplant cultivars at normal temperature, and the difference had significant positive correlation with the chilling resistance of cultivars, but it was not obvious among cultivars. The cultivars with strong resistance to chilling were easily induced by low temperature. The Pro content and its change of cultivars could represent the chilling resistance under 5掳C treatment.6. The effect of low temperature on membrane lipid peroxidation and protective enzyme system of eggplant was studied. With the decrease in temperature, the POD activity and MDA content were increased, while CAT activity was decreased and then increased again. The change of POD activity and MDA contents had significant negative correlation with chilling resistance of cultivars, and the difference was obvious among them. The cultivars with strong resistance to chilling had higher activities, less MDA content and less activities change. So it was feasible to appraise chilling resistance of different cultivars using the changes of POD activities and MDA contents.7. The correlations of eight chilling resistance indices...
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