Abstract:In order to understand the tolerance of cockscomb (Celosia cristata) seeds under short-term extreme high temperature for 30 min, the seed vigor and physiological indexes of early seedlings were studied by germination on paper. The results showed that the relative germination rate, germination energy and relative germination index of cockscomb seeds treated under 60℃ were 101.68%, 70%, 101.41%, respectively, and the relative harm rate was only-1.14%. The root length, lateral root number, root activity, chlorophyll content, SOD activity and MDA content of early seedlings had not significant difference with the control (P>0.05), but POD and CAT activities were significantly higher than the control (P<0.05). The seed vigor, CAT activity, root activity and chlorophyll content decreased with higher temperature. Therefore, the limiting temperature that cockscomb seeds could tolerant was 60℃, the CAT in cockscomb seeds was more sensitive than SOD and POD under high temperature, which could be used as an index to evaluate the reaction of plants to short-term high temperature.
