摘要
为探究长期镉胁迫对铁皮石斛抗氧化能力的影响,对铁皮石斛叶片超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性在不同浓度梯度镉胁迫中的响应关系进行研究,并建立基于logistic函数的镉胁迫SOD、CAT、POD活性变化动力学方程。结果表明:SOD、CAT、POD活性与镉浓度呈正相关,一定浓度的镉胁迫有利于提高铁皮石斛抗氧化酶活性。结合试验结果得到的模型参数表明,各胁迫水平下建立的12个模型拟合度好(R^2>0.9,P<0.05);镉胁迫浓度与铁皮石斛叶片抗氧化酶活性内禀增长率呈正相关,与环境容纳极限值和拐点时刻呈负相关;综合各模型拐点时刻及铁皮石斛生长周期,镉处理促进铁皮石斛抗氧化酶的极限浓度为2 mg·L^(-1)。因此,低浓度镉胁迫对铁皮石斛毒害较低,同时能一定程度上增加抗氧化酶的积累;logistic动力学模型可较好地反映镉胁迫下铁皮石斛叶片的动态生长过程。
In order to study the effects of cadmium（ Cd） stress on antioxidant capacity of Dendrobium officinale,experiments of response relationship between Cd stress and superoxide dismutase（ SOD）,catalase（ CAT）,and peroxidase（ POD） in D. officinale leaves were done,and dynamics equation of SOD,CAT,POD activities based on logistic function were established. The results showed that there was a positive correlation between the SOD,CAT,POD activities and Cd concentration,and the antioxidant capacity was increased when treated by certain Cd concentration. The model parameter calculation displayed that the fitting degree of 12 model under different stress level were fine（ R2 〉0. 9,P〈 0. 05）. The model parameter calculation indicated that Cd concentration was positively correlation with the intrinsic rates,while negatively correlated with the environmental capacity and inflection points. Comprehensive D. officinale growth period and all inflection points showed that the limit Cd concentration was 2 mg·L^（-1） which could improve antioxidant accumulation. Thus,low concentration of Cd stress not only had low toxicity to D.officinale,but also could increase the antioxidant accumulation to a certain extent. Dynamic model based on logistic function with Cd concentration could be a potential tool for predicting the dynamic process of D. officinale growth un-der Cd stress.
出处
《浙江农业学报》
CSCD
北大核心
2017年第9期1421-1429,共9页
Acta Agriculturae Zhejiangensis
基金
温州市公益性农业科技项目(N20150017)
浙江省农业科学院地方科技合作项目(WZ20130006
CA20150005)
浙江省农业技术推广中心中药材产业技术团队项目(浙农技[2016]54号)
关键词
铁皮石斛
镉胁迫
抗氧化酶
动力学模型
Dendrobium officinale
cadmium stress
antioxidant enzyme
dynamics model
