关键词: 猪链球菌Ⅱ型, 猪链球菌Ⅱ型

Abstract: In order to explore the activities of several enzymes and lipid peroxidation level of various growth stages of the functional leaves，and provide a reference for breeding of the early maturing potato varieties. In this paper, the early-maturing variety‘Dongnong 303’and late-maturing variety‘yanshu4th’as the test material, the enzyme activity of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and malondialdehyde (MDA) contents were tested in the potato functional leaves. The results indicated that the SOD of potato function leaves activity rising in the whole growth period; at the seedling stage MDA contents is highest and then a sharp decline in the tuber formation period the content increases slightly; at the seedling stage CAT activity is highest and then began to decrease, flowering and tuber formation change weakly .the POD activity is highest in the bud stage, after then decline tuber formation period of minimum activity. The results also show that‘Dongning 303’higher than the yanshu4 in the SOD, CAT and POD during the whole growth period, Although the growth period of the early-maturity variety is shorter，the physiological-chemical activities of its functional leaves are still rather high. This study has a certain significance of early maturing potato breeding.