Physiological Mechanism of Chilling Tolerance in Eggplant Seedling

6 materials which were different in tolerance of low temperature were carried on low-temperature treatments,15℃/10℃ in day/night for 2 days,10℃/7℃ in day/night for 10 days.Several characters such as the chilling tolerance,growth indexes(plant height,stalk diameter,fresh weight,dry weight),physiological indexes(POD activity,SOD activity,APX activity,proline content) were investigated to study the growth and physiological characteristics under low temperature stress.The results indicated that:(1)there was no big influence for others characters at normal temperature,the difference was extremely significant for all characters at low temperature.In comparison with CK's indexes plant height,stalk diameter,fresh weight,dry weight decreased and POD activity,SOD activity,APX activity,proline content increased after the low temperature treatment.(2)The relationship of chilling tolerance with uplift-descent scale of indexes ranging were osculation.The decrease range of growth indexes of high resisted materials were smaller,the increase range of physiological indexes were larger.While,the medium resisted materials revealed contrary trend.(3)Compared each indexes,chilling tolerance was significant positive correlation with plant height,stalk diameter,dry weight,POD activity,SOD activity,the correlation with others characters did not reach significant level.We can concluded that the growth of eggplant seedlings were negatively influenced by low temperature stress,but resistant materials could adjust themselves to avoid low temperature harms by regulating protective enzyme system,which led to some tolerant ability of eggplant to low temperature conditions.