Abstract

This study was carried out to evaluate Cu uptake, mobility, and accumulation in Cyperus rotundus and define the physiological strategy it employs under copper stress conditions. The experiment was performed at concentration levels from 12, 100, 150, 200, 250, and 300 mg Cu/kg in pod soil. The metal concentrations in roots, tubers, and root organs and the translocation factor (TF), total soluble sugars (TSS), and biomass production were evaluated. The results showed that the changes in TF and Cu concentrations had good fitness (p_value < 0.01; R² > 0.87) with the quadratic models. These models have indicated C. rotundus has limited Cu translocation from the roots to the shoots (0.009 < TF < 0.05). The results also showed that TSS significantly (p_value < 0.05) increased under Cu stress and changes in both the shoot and tuber tissues had good fitness with the quadratic model (R² > 0.98). In summary, C. rotundus is a hyper tolerant plant with a high ability to take up Cu from the soil, accumulate it in its underground tissues and prevent Cu translocate in above ground tissues. Therefore C. rotundus can be considered as a hyper phytostabilizer with the ability to hold Cu concentration in its shoot at a lower level than the maximum allowable concentrations in animal food and so can be recommend as safe forage in the copper contaminated environment.

• Novelty statement

• This paper reported for the first that Cyperus rotundus can be hyper Phytostabilizer if tubers and roots are considered as an unharvestable part.

• Cyperus rotundus can be suggested as a safe palatable plant due to the following three indices: (1) the maximum Cu concentration observed in the shoots is less than the maximum authorized concentration (MAC) in animal food, (2) the Translocation Factor of Cu (TF < 0.05) is very low, and (3) the physiological strategy of “excluders sensu Baker” used for copper phytostabilizing prevent more translocation and accumulation of Cu under more sever contaminated conditions, so this species could be used for grazing and forage production in copper contaminated environments.

• Safety forage assessment under a metal-contaminated environment using the three main indices described above is a novel idea.

摘要

本研究旨在评估香附中铜的吸收、流动性和积累，并确定其在铜胁迫条件下采用的生理策略。该实验在豆荚土壤中以 12、100、150、200、250 和 300 mg Cu/kg 的浓度水平进行。评估了根、块茎和根器官中的金属浓度以及易位因子 (TF)、总可溶性糖 (TSS) 和生物量产量。结果表明，TF和Cu浓度的变化与二次模型具有良好的适应性（p_值<0.01；R ² > 0.87）。这些模型表明C. rotundus从根到芽的铜易位有限 (0.009 < TF < 0.05)。结果还表明，在Cu胁迫下TSS显着增加（p_值<0.05），并且地上部和块茎组织的变化与二次模型具有良好的适应性（R ² > 0.98）。综上所述，C. rotundus是一种超耐受植物，具有从土壤中吸收铜、将其积累在地下组织中并防止铜在地上组织中易位的能力。因此C. rotundus 可以被认为是一种超级植物稳定剂，能够将其枝条中的铜浓度保持在低于动物食品中最大允许浓度的水平，因此可以推荐为铜污染环境中的安全饲料。

• 新颖性声明

• 该论文首次报道了如果将块茎和根视为不可收获的部分，香附可以是超植物稳定剂。

• 由于以下三个指标，香附可以被认为是一种安全的可口植物：（1）在芽中观察到的最大铜浓度低于动物食品中的最大授权浓度（MAC），（2）铜的易位因子( TF < 0.05) 非常低，并且 (3) 用于铜植物稳定的“excluders sensu Baker”生理策略防止在更严重的污染条件下更多的铜易位和积累，因此该物种可用于放牧和牧草生产在铜污染的环境中。

• 使用上述三个主要指标评估金属污染环境下的安全饲草是一个新颖的想法。