Response of Cucubita pepo Seedlings to Low Temperature and Weak Light and Evaluation Index Screening

In this experiment,the zucchini inbred lines tolerant ‘Saiyu Female Parent’‘Xianyibai 12’‘Jinghu 33’ and intolerant ‘Hou 5 Male Parent’‘08-13 Male Parent’‘Jinghu No.1’ to low temperature and weak light were used as test materials.In order to screen the evaluation index of low temperature and weak light of zucchini,the effects of low temperature and weak light on the growth index,physiological index and coefficient of cold damage of zucchini were studied by using four different combinations of low temperature and weak light.The results showed that the variation of hypocotyl length and leaf area decreased,dry and fresh weight above ground decreased,the content of proline increased and then decreased,the content of soluble protein decreased,the activities of root became weaker,the activity of SOD and CAT decreased,the activity of POD and content of MDA increased,and the coefficient of cold damage index increased.The variation of hypocotyl length,dry and fresh weight above ground,and cold injury index of zucchini seedlings could be used as the evaluation index of low temperature and weak light tolerance in the seedling stage of zucchini.