Hussain Tabassum, Asrar Hina, Zhang Wensheng, Liu Xiaojing
CAS Engineering Laboratory for Efficient Utilization of Saline Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang, China.
Dr. M. Ajmal Khan Institute of Sustainable Halophyte Utilization, University of Karachi, Karachi, Pakistan.
Front Plant Sci. 2023 Apr 21;14:1091292. doi: 10.3389/fpls.2023.1091292. eCollection 2023.
Soil salinity and water deficit often occur concurrently, but understanding their combined effects on plants' ion regulation is limited. With aim to identify if introducing drought with salinity alleviates salt stress's ionic effects, - a halophytic grass- was grown in the presence of single and combined stressors, i.e., drought and salt (low and high). Regulation of cations and anions along with the antioxidant capacity and modifications in leaf anatomy were investigated. Results showed a combination of low salt and drought minimally affected plant (dry) mass by improving the selective ions absorption and nutrient use efficiencies. The lowest ratio for efficiency of photosystem II and carbon assimilation (ΦPSII/ΦCO) suggested less generation of reactive oxygen species, which were probably detoxified with constitutively performing antioxidant enzymes. In contrast, the combination of high salinity and drought escalated the adverse effects caused due to individual stressors. The selective ion absorption increased, but the non-selective ions transport caused an ionic imbalance indicating the highest ratio of Na/K. Although the area of mesophyll increased, a reduction in epidermis (cell number and area) predicted a mechanical injury prone to water loss in these plants. The compromised activity of antioxidant enzymes also suggested treatment-induced oxidative damage. Yet, the synergistic interaction between high salinity and drought was not detrimental to the survival of Therefore, we suggest planting this grass in habitats with harsh environmental conditions to meet the increasing fodder demands without compromising agricultural lands' productivity.
土壤盐渍化和水分亏缺常常同时发生,但对它们对植物离子调节的综合影响的了解有限。为了确定在盐分环境中引入干旱是否能减轻盐胁迫的离子效应,一种盐生草在单一和复合胁迫因素(即干旱和盐分,包括低盐和高盐)存在的情况下生长。研究了阳离子和阴离子的调节以及抗氧化能力和叶片解剖结构的变化。结果表明,低盐和干旱的组合通过提高选择性离子吸收和养分利用效率,对植物(干)质量的影响最小。光系统II和碳同化效率(ΦPSII/ΦCO)的最低比率表明活性氧的产生较少,这些活性氧可能通过持续发挥作用的抗氧化酶被解毒。相比之下,高盐度和干旱的组合加剧了由单一胁迫因素引起 的不利影响。选择性离子吸收增加,但非选择性离子运输导致离子失衡,表明Na/K比率最高。尽管叶肉面积增加,但表皮(细胞数量和面积)的减少预示着这些植物容易因水分流失而受到机械损伤。抗氧化酶活性的受损也表明处理诱导了氧化损伤。然而,高盐度和干旱之间的协同相互作用对该盐生草的存活并无不利影响。因此,我们建议在恶劣环境条件的栖息地种植这种草,以满足不断增长的饲料需求,同时不影响农田的生产力。