Testa Giorgio, Ciaramella Barbara Rachele, Fernando Ana Luisa, Kotoula Danai, Scordia Danilo, Gomes Leandro Augusto, Cosentino Salvatore Luciano, Alexopoulou Efthymia, Papazoglou Eleni G
Dipartimento di Agricoltura, Alimentazione e Ambiente (Di3A), University of Catania, Via Santa Sofia 100, 95123 Catania, Italy.
MEtRICs, CubicB, Chemistry Department (DQ), NOVA School of Science and Technology|NOVA FCT, Universidade Nova de Lisboa, Campus de Caparica, 2829-516 Caparica, Portugal.
Plants (Basel). 2024 Sep 24;13(19):2671. doi: 10.3390/plants13192671.
The dwindling availability of agricultural land, caused by factors such as rapid population growth, urban expansion, and soil contamination, has significantly increased the pressure on food production. To address this challenge, cultivating non-food crops on contaminated land has emerged as a promising solution. This approach not only frees up fertile soil for food production but also mitigates human exposure to contaminants. This work aimed to examine the impact of soil contamination with Cd, Pb, Ni, and Zn on the growth, productivity, metal accumulation, and the tolerance of five lignocellulosic non-food crops: switchgrass ( L.), biomass sorghum ( L. Moench), giant reed ( L.), African fodder cane ( L. spp. Willd. Hackel), and miscanthus ( × Greef et Deu.). A two-year pot experiment was conducted in Greece, Italy, and Portugal, following the same protocols and applying various levels of metals: Cd (0, 4, 8 mg kg), Pb and Zn (0, 450, 900 mg kg), and Ni (0, 110, 220 mg kg). The experimental design was completely randomized, with three replicates for each treatment. The results showed that switchgrass and sorghum generally maintained their height and productivity under Cd and Pb stress but were adversely affected by high Zn and Ni concentrations. Giant reed and African fodder cane showed reduced height and productivity at higher Ni and Zn levels. Miscanthus exhibited resilience in height but experienced productivity reductions only at the highest Zn concentration. Heavy metal uptake varied among crops, with switchgrass and sorghum showing high Cd and Pb uptake, while giant reed accumulated the most Cd and Zn. Miscanthus had the highest Ni accumulation. The tolerance indices indicated that switchgrass and sorghum were more tolerant to Cd and Zn at lower concentrations, whereas miscanthus had lower tolerance to Cd but a higher tolerance to Zn at higher concentrations. Giant reed and African fodder cane demonstrated stable tolerance across most heavy metals. Accumulation indices highlighted the effectiveness of switchgrass and sorghum in Cd and Pb uptake, while miscanthus excelled in Ni and Zn accumulation. The cluster analysis revealed similar responses to heavy metal stress between African fodder cane and giant reed, as well as between sorghum and miscanthus, with switchgrass displaying distinct behavior. Overall, the study highlights the differential tolerance and accumulation capacities of these crops, indicating the potential for phytoremediation applications and biomass production in heavy metal-contaminated soils.
由于人口快速增长、城市扩张和土壤污染等因素导致农业用地日益减少，这显著增加了粮食生产的压力。为应对这一挑战，在受污染土地上种植非粮食作物已成为一种有前景的解决方案。这种方法不仅为粮食生产腾出了肥沃土壤，还减少了人类接触污染物的机会。本研究旨在考察镉、铅、镍和锌污染土壤对5种木质纤维素非粮食作物生长、生产力、金属积累及耐受性的影响，这5种作物分别为柳枝稷（Panicum virgatum L.）、生物质高粱（Sorghum bicolor L. Moench）、巨菌草（Arundo donax L.）、非洲饲料甘蔗（Saccharum officinarum L. spp. Willd. Hackel）和芒草（Miscanthus × giganteus Greef et Deu.）。在希腊、意大利和葡萄牙开展了一项为期两年的盆栽试验，试验遵循相同的方案并施加不同水平的金属：镉（0、4、8毫克/千克）、铅和锌（0、450、900毫克/千克）以及镍（0、110、220毫克/千克）。试验设计为完全随机，每个处理设置3次重复。结果表明，在镉和铅胁迫下，柳枝稷和高粱的株高和生产力总体上保持稳定，但高浓度的锌和镍对其产生了不利影响。在较高的镍和锌水平下，巨菌草和非洲饲料甘蔗的株高和生产力降低。芒草的株高表现出一定的恢复能力，但仅在最高锌浓度下生产力有所下降。不同作物对重金属的吸收情况各异，柳枝稷和高粱对镉和铅的吸收量较高，而巨菌草积累镉和锌的量最多。芒草积累镍的量最高。耐受性指数表明，在较低浓度下，柳枝稷和高粱对镉和锌的耐受性更强，而在较高浓度下，芒草对镉的耐受性较低，但对锌的耐受性较高。巨菌草和非洲饲料甘蔗对大多数重金属表现出稳定的耐受性。积累指数突出了柳枝稷和高粱在镉和铅吸收方面的有效性，而芒草在镍和锌积累方面表现出色。聚类分析表明，非洲饲料甘蔗和巨菌草对重金属胁迫的反应相似，高粱和芒草也相似，而柳枝稷表现出独特的行为。总体而言，该研究突出了这些作物不同的耐受性和积累能力，表明它们在重金属污染土壤中具有植物修复应用和生物质生产的潜力。
