Effect of the Chilling Tolerance on Antioxidant Enzymes Activity during Maize Seed Germination

In order to explore the regulation mechanism of cold resistance at the maize seed germination stage,taking the difference maize hybrids(Zhengdan 958,Jidan 415,Tiedan 18 and Liaodan 632) as experimental materials,the changes of antioxidant enzymes activity at maize seed germination stage were studied under 10℃ and 27℃.The results showed that the changes of antioxidant enzymes showed dramatically fluctuant trend under not only low but also suitable temperature.The activities of SOD were increased continuously since the treatments of chilling-resistance(Zhengdan 958 and Jidan 415),and both higher than Liaodan 632 and Tiedan 18.The activity of POD was decreased at first and then increased of a single peak curve,peak appeared earlier and higher of Zhengdan 958 and Jidan 415 than Tiedan 18 and Liaodan 632 under10℃ and 27℃.The activity of CAT was 0 before maize seed germination,the chilling-resistance cultivars showed high increased trend than chilling-sensitive cultivars.