PRSV对番木瓜叶片防御酶活性的影响

The effect of PRSV on defense enzymes activity in leaf of Papaya

对不同抗性番木瓜(Carica papayaL.)品种人工接种番木瓜环斑型花叶病毒病(Papaya ringspot virus,PRSV)Ys株系,分析其抗病性与叶片中POD、PPO及SOD等防御酶活性及POD同工酶变化的关系.结果表明,接种PRSV-Ys后,抗病突变体“岭抗1号”(暂名)的POD和PPO活性先升后降,上升幅度明显高于感病品种穗中红,后期POD和PPO活性则低于穗中红;SOD活性在初期升高,后期则恢复到正常水平.“岭抗1号”叶片POD同工酶增加1条谱带Rf 0.745.POD同工酶组成型表达及酶活性的变化与抗病相关,可作为评价抗病性的生理生化指标.

The changes of POD, PPO and SOD activities and POD isozyme in leaves were determined before and after infected with PRSV- Ys in a natural resistant mutant of papaya. The results showed that after infected the activities of POD and PPO in the natural resistant mutant were higher than those in susceptible cultivar Suizhonghong, and the POD and PPO increased at early stage and then decreased, and the changes in POD and PPO activities in the natural resistant mutant increased more than that of Suizhonghng. The SOD activities in Suizhonghng increased more than that of the natural resistant mutant. A POD isozyme band （Rf 0.745 ） appeared in the natural resistant mutant, which did not occurred in resistant variety. The changes in defense enzyme activity and POD isozyme showed much close relation to the resistance to PRSV in papaya.