矿区生态型和非矿区生态型蜈蚣草对铅胁迫的生理响应

探讨不同矿区生态型蜈蚣草对铅的耐性及其耐铅机理,为进一步研究蜈蚣草植物修复射击场土壤的铅污染提供理论依据。在水培铅胁迫的环境条件,对矿区生态型和非矿区生态型蜈蚣草生长过程中的生物量、色素含量、MDA质量摩尔浓度和CAT,POD,SOD活性等进行了研究。研究发现,营养液中铅的加入抑制了蜈蚣草的生长,降低了羽叶中的色素含量,大幅度提高了MDA质量摩尔浓度和CAT,POD,SOD活性。结果表明,蜈蚣草对铅有一定的耐性,并且矿区生态型蜈蚣草的耐性明显高于非矿区生态型。主要表现为矿区生态型蜈蚣草的抗氧化酶活性高于非矿区生态型,生物量和色素含量受铅胁迫影响的程度相对较小。当铅质量浓度达到300 mg/L,铅胁迫15 d后,非矿区生态型蜈蚣草抗氧化酶系统紊乱,植株接近枯死状态,而矿区生态型蜈蚣草的耐性表现相对较好。

Physiological Reaction to Lead Stress of Metallicolous and Nonmetallicolous Populations of Pteris Vittata L.

In this paper, the tolerance of metallicolous and nonmetallicolous populations of Pteris vittata L. to lead stress was explored in order to provide theoretical basis for phytoremediation of lead pollution in shooting range soil in further research. The biomass, activities of SOD, POD, CAT and content of pigment, MDA of metallieolous and nonmetallicolous populations of Pteris vittata L. in lead stress were resear, ehed through water culture method. In research it is found that the adding of lead in nutrient solu- tion inhibited the growth of Pteris vittata L., lowered the content of pigment, the content of MDA and the activities of CAT, POD, SOD went obviously up. The restlh showed that, Pteris vittata L. had a certain tolerance to lead, and the tolerance of metallicolous populations of Pteris vittata L. was significantly higher than nonmetallieolous populations of Pteris vittata L.. Mainly behaviors in- eluding activities of antioxidant enzyme of metallicolous was higher than nonmetallicolous, and small effect of lead stress on bio- mass and content of pigment of metallieolous. After lead stress for 15 days, the antioxidant system of nonmetallicolous was in disor- der when the lead content reached 300 mg/L in nutrient solution, and the plant went near to dead, but the metallicolous population of Pteris vittata L. showed a better tolerance in contrast.