【摘要】 利用褐土和红富士苹果嫁接苗为供试材料 ,研究外源铜对土壤—苹果树系统中酶活性的影响。结果表明 ,低量的外源铜能使果树叶片的过氧化氢酶、多酚氧化酶、抗坏血酸氧化酶及根系过氧化氢酶的活性加强 ,而高量铜使活性大幅度降低 ,加入钙铁后在一定程度上使抑制缓解。土壤过氧化氢酶的活性与外源铜量具显着的曲线相关性 ,(y =x ( - 1 1 .2 6+ 0 .75x) ,r=0 .995 5 ) ,蔗糖酶活性与土壤施铜量呈Logistic函数关系 (y =2 .95 ( 1 + 0 .5 7exp( - 5 .0 2× 1 0 - 5x) ,r=- 0 .982 0 )。脲酶对铜过量非常敏感 ,大于 1 0 0mgkg- 1的各处理均未测出其活性更多还原

【Abstract】 Effect of external copper on enzyme activity in a soil and apple tree system was studied by using cinnamon soil and ’Fuji’ apple young tree. The results showed that perioxidase, PPO and ascorbic acid oxidase activity in the leaves and perioxidase activity in the roots were reinforced at low external copper levels and reduced at high. Adding Ca of Fe at high copper levels could mitigate copper toxicity in some degree. A significant curuilinear correlation was observed between soil perioxidase activity and the external copper concentration (?y=x/(-11.26+0.75x), r=a(c)0.9955a?a(c)** ). ? Soil sucrase activity was logistically correlated with the external copper level (?y=a(c)2.95 /(1+0.57?exp(-5.02?á10a?a(c)-5 ?x)),r=-0.9820a?a(c)** ?). Urease was very sensitive to copper and it lost activity at levels>Cu100.更多还原