水分胁迫对燥红土和变性土上生长的玉米叶片几种酶活性的影响

采用盆栽控制试验，研究了不同处理条件下，水分胁迫对金沙江干热河谷典型土壤(燥红土和变性土)生长的玉米(Zea mays L.)叶片中几种酶活性的影响．结果表明：(1)在一定的水分胁迫范围内，玉米叶片的过氧化物酶(POD)、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(ASP)和多酚氧化酶(PPO)活性均随着土壤含水量的降低而升高，但过度胁迫时，酶活性降低；(2)随着土壤含水量降低，玉米叶片中保护酶活性的变化规律略有差异，这与二者的土壤物理性质有关；(3)施肥处理和栽培方式对玉米叶片的酶活性有影响，增施有机肥和Zn肥可提高适度水分亏缺条件下玉米叶片中POD、CAT、ASP和PPO活性．图4参35

EFFECTS OF WATER STRESS ON ACTVITIES OF PROTECTIVE ENZYMES IN LEAVES OF MAIZE (ZEA MAYS L.) GROWN IN DRY-RED SOIL AND VERTISOL

The soil water contents including 25%,20%,15% and 10% control by weighing method,and pot control experiments were adopted to investigate the effects of soil water stress on several enzyme activities in leaves of maize growing in the typical soils (dry-red soil and vertisol) in the Jinsha River hot-dry valley,where maize monoculture or mixed cropping with maize and tamarind ( Tamarindus indica ) tree was carried out under different treatments. After 30 days for soil water control in the experiment,the activities of peroxidase (POD),catalase (CAT),ascorbic acid peroxidase (ASP) and polyphenol oxidase (PPO) in the second maize leaves from the top were analyzed. The results indicated: (1) within a certain range of soil water content,the activities of POD,CAT,ASP and PPO in maize leaves increased with the decrease of soil water content,but decreased when reached the over-stress level; (2) changes of the enzyme activities were slightly different with the decrease of soil water content depending on soil physical features; (3) fertilization and culture type played a certain role in protective enzyme activities in maize leaves,and supplement of organic fertilizer and Zn could improve the activities of POD,CAT,ASP and PPO in maize leaves under certain water deficit. Fig 4,Ref 35