Abstract The lack of natural resources, especially good-quality cropland and renewable water resources is threatening food production potential in marginal agricultural ecosystems, which are already negatively affected by climate change. Since the world's major crops are proving inadequate to supply the calories and nutrients for people in these areas, new crops are sought that can withstand harsh ecological environmental conditions. In the current trial, we assessed the growth and productivity of Tetragonia tetragonioides (Pallas) Kuntz. in a floating hydroponic system supplied with different seawater proportions (i.e. 15% and 30% seawater, EC = 9.8 and 18.0 dS m−1). Moreover, the effects of different salinity levels on mineral elements accumulation, production of osmotic solutes and secondary metabolites were determined, along with the salt removal capacity of the crop. The results indicated that plant growth was not affected by either of the seawater treatments used in this study. The increased leaf succulence and the reduction of both leaf area and specific leaf area with increasing salinity might represent an essential feature of this salt-tolerant species associated to the plants need of limiting transpiration. Low seawater treated plants showed a significantly higher biomass yield per liter of (sea)water used (117%) than the control. Under these conditions plants accumulated the highest amount of Mg (+31% and 48% in medium and high seawater treated plants compared with the control) and Cu (+14% and 30%, respectively) along with increasing proline and decreasing nitrate concentrations. By contrast, we found that seawater supply resulted in a Na-enriched leaf biomass that may represent an issue for human health. We concluded that Tetragonia tetragonioides can be grown in saline agriculture up to a salinity level characterized by an EC of 18 dS m-1 but further investigation is required to address Na accumulation in leaves.

中文翻译：

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Tetragonia tetragonioides (Pallas) Kuntz。在盐碱地农业环境中作为有前途的耐盐作物

摘要 自然资源的缺乏，特别是优质农田和可再生水资源的缺乏正在威胁着边缘农业生态系统的粮食生产潜力，这些生态系统已经受到气候变化的负面影响。由于世界上的主要农作物已证明不足以为这些地区的人们提供热量和营养，因此需要寻找能够承受恶劣生态环境条件的新农作物。在当前的试验中，我们评估了 Tetragonia tetragonioides (Pallas) Kuntz 的生长和生产力。在提供不同海水比例（即 15% 和 30% 海水，EC = 9.8 和 18.0 dS m-1）的浮动水培系统中。此外，还确定了不同盐度水平对矿物元素积累、渗透溶质和次生代谢物产生的影响，以及作物的除盐能力。结果表明植物生长不受本研究中使用的任何一种海水处理的影响。随着盐度的增加，叶肉质增加以及叶面积和比叶面积的减少可能代表了这种与植物需要限制蒸腾作用相关的耐盐物种的基本特征。与对照相比，低海水处理植物每升使用的（海）水显示出显着更高的生物量产量（117%）。在这些条件下，随着脯氨酸浓度的增加和硝酸盐浓度的降低，植物积累了最高量的镁（与对照相比，中高海水处理植物中的镁含量分别为+31% 和 48%）和铜（分别为+14% 和 30%）。相比之下，我们发现海水供应导致富含钠的叶生物量可能代表人类健康问题。我们得出结论，Tetragonia tetragonioides 可以在含盐农业中生长，其盐度水平以 EC 为 18 dS m-1 为特征，但需要进一步研究以解决叶片中 Na 的积累问题。