玉米不同品种接种MDMV后叶片内过氧化物酶及其同工酶的变化

The changes of PO and its isoenzymes in leaves of different maize varieties after inoculation with MDMV

对4个感病程度不同的玉米品种接种玉米矮化花叶病毒（MDMV）7d后植株叶片内过氧化物酶（PO）活性经研究表明：玉米接种病毒后PO活性均有提高，但提高幅度不同且酶活变化波形差异大。抗病品种接毒前酶活低且波形变化平稳，接毒后第2天酶活急剧增高且波形变化大，而感病品种接毒后酶活变化不大且波形一致。玉米PO同工酶酶谱简单，与对照比较，接毒后抗、感品种带纹数目变化不大，但带纹浓重而重叠。抗病品种接毒后第2天带纹突然加重，且持续增加，而感病品种有持续减弱趋势。

The PO activities in the leaves of four baize varieties with different susceptibility to maize dwarf mosaic virus (MDMV) were tested within one week after the plants were inoculated with the virus. Results showed that peroxide (PO) activities in the leaves of all varieties were increased after virus inoculation, but raised quite different. Before inoculation the enzyme activities in the resistant varieties were low and the changeS in activities of PO were stable. In addition, the enzyme activities increased rapidly and there were no significant changes in the second day after inoculation. However, the activities in susceptible varieties both before and after inoculation were showed little difference and the changes in the enzyme activities were not great. The isoenzyme bands of PO in maize were simple. The variation of numbers in bends of resistant and susceptible varieties after inoculation was small, but the patterns were stronger than those in control. On the second day after inoculation the colors of the bands in resistant varieties were deepened suddenly and increased continuously, but decreased in the susceptible ones.