种植密度与留叶数对打顶后烤烟几种酶活性和MDA含量的影响

在不同种植密度和留叶数条件下，对烤烟不同生育期各部位叶片的超氧化物歧化酶（S0D）、过氧化物酶（POD）、多酚氧化酶（PPO）和淀粉酶及丙二醛（MDA）含量进行了研究，结果表明:1）随着种植密度的增加，上、中、下3个部位烟叶中的SOD和淀粉酶的活性总的趋势是上升的，MDA的含量上升，而POD和PPO的活性则表现为下降。2）随着留叶数减少，各部位叶片中SOD、POD、PPO和淀粉酶活性减弱，MDA含量增加。3）综合分析认为，1100株/667m2，留叶数24片/株的处理效果最好，其次是1300株/667m2与22片/株处理,1100株/667m2,留叶数18片/株处理的效果较差。 

Effects of plant density and leaf population on activities of several enzymes and MDA content of flue-cured tobacco

SOD, POD, PPO, amylase, and MDA content were studied during the growth of flue-cured tobacco in different plant density and leaf numbers. Results showed that with the increase of plant density, MDA content increased and the activities of SOD and amylase were improved while those of POD and PPO were reduced. With the decrease of leaf number, activities of SOD, POD, PPO and amylase were reduced and MDA content increased. According to the comprehensive analysis, the treatment of 1100 plants/667m2 and 24 leaves per plant was the best, the treatment of 1300 plants/667m2 and 22 leaves per plant took the second place, and the treatment of 1100 plants/667m2 and 18 leaves per plant was relatively low.