Faculty of Animal Science and Technology, Yunnan Agricultural University, 650201, Kunming, China.
College of Resources and Environment, Yunnan Agricultural University, 650201, Kunming, China.
BMC Plant Biol. 2022 Mar 25;22(1):145. doi: 10.1186/s12870-022-03475-2.
Cadmium (Cd) and arsenic (As) exist simultaneously in soil environment, which poses a serious threat to the safety of agricultural products and forage production. Four Perennial Ryegrass (Lolium perenne L.) cultivars with different accumulation characteristics ('Nicaragua', 'Venus', 'Excellent' and 'Monro') were selected as the material for pot experiment. The coupled responses of key components and related enzyme activities under combined stresses of Cd and As were investigated. key components contents include Non protein sulfhydryl (NPT), glutathione (GSH) and phytochelatins (PCs). The related enzyme includes (superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), γ-glutamylcysteine synthetase (γ-ECS), glutathione synthetase (GSS), phytochelatin synthetases (PCSase) and arsenate reductase (AR). The results showed that Cd contents of perennial ryegrass were higher than those of As contents with TF < 1. Cd and As contents in roots were in the higher proportion than those in shoots. Compared to control, POD activities increased by 2.72 folds under 120 mg kg As treatment. The contents of PCs increased by 5.68 folds under 120 mg kg As treatment. Under combined Cd and As stress, the MDA contents and antioxidant enzyme activities of 'Venus' were higher than those of 'Nicaragua'. 'Nicaragua', a high accumulation cultivar. Under the combined stresses of Cd and As, the enzyme activities and the key components were significantly correlated (P < 0.05) with the contents of Cd and As. The tolerance to Cd and As was improved with increase in GSH and PCs contents and γ-ECS, GSS, PCSase and AR activities. In conclusion, the antioxidant enzyme system and key resistant substances of perennial ryegrass have important and antagonistic effects on Cd and As stresses.
镉（Cd）和砷（As）同时存在于土壤环境中，对农产品和饲料生产的安全构成严重威胁。选用具有不同积累特性的多年生黑麦草（Lolium perenne L.）4 个品种（‘尼加拉瓜’、‘金星’、‘优秀’和‘门罗’）为材料进行盆栽试验。研究了 Cd 和 As 联合胁迫下关键组分及其相关酶活性的耦合响应。关键组分含量包括非蛋白巯基（NPT）、谷胱甘肽（GSH）和植物螯合肽（PCs）。相关酶包括（超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、γ-谷氨酰半胱氨酸合成酶（γ-ECS）、谷胱甘肽合成酶（GSS）、植物螯合肽合成酶（PCSase）和砷酸盐还原酶（AR）。结果表明，多年生黑麦草中 Cd 含量高于 As 含量，转移系数（TF）<1。根中的 Cd 和 As 含量比例高于地上部分。与对照相比，120mgkg As 处理下 POD 活性增加了 2.72 倍。120mgkg As 处理下 PCs 含量增加了 5.68 倍。在 Cd 和 As 联合胁迫下，‘金星’的 MDA 含量和抗氧化酶活性高于‘尼加拉瓜’。‘尼加拉瓜’是一个高积累品种。在 Cd 和 As 联合胁迫下，酶活性和关键组分与 Cd 和 As 含量呈显著相关（P<0.05）。随着 GSH 和 PCs 含量以及 γ-ECS、GSS、PCSase 和 AR 活性的增加，Cd 和 As 的耐受性得到提高。综上所述，多年生黑麦草的抗氧化酶系统和关键抗性物质对 Cd 和 As 胁迫具有重要的拮抗作用。
