干旱对玉米叶中超氧物岐化酶和过氧化氢酶活性的影响

在干旱胁迫下,玉米叶细胞中超氧物岐化酶(SOD)和过氧化氢酶(CAT)的活性下降,其失活程度随胁迫强度的增大而加重;膜脂过氧化产物丙二醛(MDA)含量上升及膜透性增加与SOD、CAT活性变化趋势相同;过度干旱对SOD活性的影响在复水10天时仍较明显;对不同强度干旱胁迫的生理反应最终表现在籽粒产量变化上,胁迫强度愈大,生理干扰愈重,产量愈低。

Effects of Drought on SOD, CAT Activities in leaves of Maize

The experiments in effects of drought on physiology and yield in maize (variety Danyu 13) were conducted in pots. Drought treatments at three levels--mild, moderate and servere stress were forced during female floret differentiation, flowering and filling stages. Water stress lasted 7 days. The experimental results indicated that SOD, CAT activities in leaves declined markedly under moderate and servere stress, but MDA contents changed in reverse direction. There was significant negative correlation between SOD, CAT activities and MDA contents; membrane permeability inereased with MDA contents; MDA contents dropped more rapidly than SOD activities increased 10 days after reirrigation; grain yield was reduced under drought conditions, and it decreased greatly as water deficit was servere; the variation tendency of grain yield was similar to that of SOD, CAT activities, which suggests that influence of drought on maize be associated with being out of balance between formation and elimination of active oxygen in plants.