Bouteraa Mohamed Taieb, Mishra Avinash, Romdhane Walid Ben, Hsouna Anis Ben, Siddique Kadambot H M, Saad Rania Ben
Biotechnology and Plant Improvement Laboratory, Centre of Biotechnology of Sfax, University of Sfax, B.P '1177', Sfax 3018, Tunisia.
CSIR-Central Salt and Marine Chemicals Research Institute, Bhavnagar 364002, India.
Plants (Basel). 2022 Jul 30;11(15):1991. doi: 10.3390/plants11151991.
Bioactivities of polysaccharides derived from halophyte plants have gained attention in recent years. The use of biostimulants in agriculture is an innovative method of dealing with environmental stressors affecting plant growth and development. Here, we investigated the use of natural polysaccharides derived from the halophyte plant (PSLm) as a biostimulant in durum wheat seedlings under salt stress. Treatment with polysaccharide extract (0.5, 1, and 2 mg/mL PSLm) stimulated in vitro wheat growth, including germination, shoot length, root length, and fresh weight. PSLm at 2 mg/mL provided tolerance to plants against NaCl stress with improved membrane stability and low electrolyte leakage, increased antioxidant activities (catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD)), enhanced leaf chlorophyll fluorescence, proline, and total sugar contents, decreased lipid peroxidation (MDA), and reactive oxygen species (HO) levels, and coordinated the efflux and compartmentation of intracellular ions. The expression profile analyses of ten stress-related genes (NHX1, HKT1.4, SOS1, SOD, CAT, GA20-ox1, GA3-ox1, NRT1.1, NRT2.1, and GS) using RT-qPCR revealed the induction of several key genes in durum wheat growing in media supplemented with PSLm extract, even in unstressed conditions that could be related to the observed tolerance. This study revealed that PSLm extract contributes to salt tolerance in durum wheat seedlings, thereby enhancing their reactive oxygen species scavenging ability, and provided evidence for exploring PSLm as a plant biostimulant for sustainable and organic agriculture.
近年来，盐生植物来源的多糖的生物活性受到了关注。在农业中使用生物刺激剂是应对影响植物生长发育的环境压力源的一种创新方法。在此，我们研究了盐生植物来源的天然多糖（PSLm）作为生物刺激剂在盐胁迫下硬粒小麦幼苗中的应用。用多糖提取物（0.5、1和2mg/mL PSLm）处理可刺激小麦体外生长，包括发芽、茎长、根长和鲜重。2mg/mL的PSLm使植物对NaCl胁迫具有耐受性，提高了膜稳定性并降低了电解质渗漏，增加了抗氧化活性（过氧化氢酶（CAT）、过氧化物酶（POD）和超氧化物歧化酶（SOD）），增强了叶片叶绿素荧光、脯氨酸和总糖含量，降低了脂质过氧化（MDA）和活性氧（HO）水平，并协调了细胞内离子的外流和区室化。使用RT-qPCR对十个胁迫相关基因（NHX1、HKT1.4、SOS1、SOD、CAT、GA20-ox1、GA3-ox1、NRT1.1、NRT2.1和GS）的表达谱分析显示，在添加PSLm提取物的培养基中生长的硬粒小麦中，即使在未受胁迫的条件下，几个关键基因也被诱导，这可能与观察到的耐受性有关。这项研究表明PSLm提取物有助于硬粒小麦幼苗的耐盐性，从而增强其活性氧清除能力，并为探索将PSLm作为可持续和有机农业的植物生物刺激剂提供了证据。
