棕壤中长期低剂量铜胁迫对苹果幼树的毒性效应  

Toxic Effects of Long-term Low-dose Copper(Cu) Stress on Apple Trees in Brown Soils

作　　者：阚世红[1] 孙百晔[2] 刘春生[3] 

机构地区：[1]潍坊学院生物工程学院,山东潍坊261061 [2]四川农业大学资源环境学院农业环境工程四川省重点实验室,四川雅安625014 [3]山东农业大学资源环境学院,山东泰安271018

出　　处：《农业环境科学学报》2010年第1期38-42,共5页Journal of Agro-Environment Science

基　　金：四川省教育厅重点项目(08ZA073);潍坊学院自然科学理论研究项目青年项目(2008Z021)

摘　　要：通过600d的土培试验,研究了棕壤中土壤环境质量二级标准附近的低剂量Cu长期胁迫对苹果幼树(藤木一号/八棱海棠)生长的毒害效应,并利用PAGE同工酶电泳研究了植株的保护性反应。结果表明,苹果树通过增强4条过氧化物酶(peroxidases,POD)同工酶的表达,弥补了6条POD同工酶活性的降低,使POD总活性显著增强(P<0.05),叶片细胞膜透性未出现显著变化(P>0.05),在一定程度上保护了机体免于长期胁迫致死;但是长期低剂量铜胁迫(160～320mg·kg-1)仍导致苹果树生长迟缓,春梢快速生长期推迟17～37d,土壤施加铜160和240mg·kg-1的苹果树生物量比对照分别降低25.87%和29.84%(P<0.01),而且胁迫600d后所有铜处理植株根系均伴有感染真菌病害(白纹羽病)的间接毒害效应。表明长期的、即使是低剂量的铜胁迫仍会对苹果树生长造成显著的毒害效应,土壤铜含量在土壤环境质量标准(果园二级标准为150～200mg·kg-1)附近的果园重金属铜污染问题仍需引起进一步重视。To study the toxic effects of long-term （600 d ） low-dose （around the second level of soil environmental quality standard ） copper （Cu）stress on the growth of young apple trees[Malus pumila Mill（ OBIR-2T-47 ）/M. micromalus Makino] in brown soils, 600 d soil culture experiments were done. And the protective reaction of the plants was analyzed using polyacrylamide gel electrophoresis（PAGE ）. Results showed that, the reactivity of six bands of peroxidase （POD）isoenzyme were lowered, and the expression of four bands of POD isoenzyme were enhanced, which lead to the significant enhanced total activity of POD in young apple trees（P〈0.05 ）; And non-significant change of elec- trolyte leakage of leaf was observed. These protective reactions helped the young apple tree to survive under the long-term Cu stress. Howev- er, long-term Cu stress do have adverse effect on the growth of the apple trees：the starting time of branch rapid growth was delayed for 17-37 d with long-term Cu treatments （160-320 mg. kg-1 ）; Meanwhile, the amount of biomass production significantly decreased （P〈0.01） by 25.87% and 29.84% with 160 mg. kg-1 and 240 mg.kg-1 Cu treatments, respectively. Also, indirect toxic symptoms were observed that trees （roots）were all infected by the fungi disease-rosellinia trunk rot after 600 d Cu stress. All of these results indicated that long term low-dose Cu tress had significant adverse effect on the growth of apple trees, so more attention should be paid to Cu contamination in orchard soils with Cu concentration around environmental quality standard（ 150-200 mg.kg-1 for orchard soils ）.

关 键 词：棕壤 苹果树 低剂量长期胁迫 铜毒害 POD同工酶 真菌病害 

分 类 号：X503.235[环境科学与工程—环境工程]