Abstract：
Drought and salt stress negatively influence the growth and development of various plant species. Thus, it is crucial to overcome these stresses for sustainable agricultural production and the global food chain. Therefore, the present study investigated the potential effects of exogenous silicon nanoparticles (SiNPs) on the physiological and biochemical parameters, and endogenous phytohormone contents of Elymus sibiricus under drought and salt stress. Drought stress was given as 45% water holding capacity, and salt stress was given as 120 mM NaCl. The seed priming was done with different SiNP concentrations: SiNP1 (50 mg L-1), SiNP2 (100 mg L-1), SiNP3 (150 mg L-1), SiNP4 (200 mg L-1), and SiNP5 (250 mg L-1). Both stresses imposed harmful impacts on the analyzed parameters of plants. However, SiNP5 increased the chlorophylls and osmolyte accumulation such as total proteins by 96% and 110% under drought and salt stress, respectively. The SiNP5 significantly decreased the oxidative damage and improved the activities of SOD, CAT, POD, and APX by 10%, 54%, 104%, and 211% under drought and 42%, 75%, 72%, and 215% under salt stress, respectively. The SiNPs at all concentrations considerably improved the level of different phytohormones to respond to drought and salt stress and increased the tolerance of Elymus plants. Moreover, SiNPs decreased the Na+ and increased K+ concentrations in Elymus suggesting the reduction in salt ion accumulation under salinity stress. Overall, exogenous application (seed priming/dipping) of SiNPs considerably enhanced the physio-biochemical and metabolic responses, resulting in an increased tolerance to drought and salt stresses. Therefore, this study could be used as a reference to further explore the impacts of SiNPs at molecular and genetic level to mitigate abiotic stresses in forages and related plant species.
摘要：
干旱和盐胁迫对各种植物的生长发育产生负面影响。因此，克服这些压力对于可持续农业生产和全球食物链至关重要。因此,本研究调查了外源硅纳米颗粒（SiNPs）对生理和生化参数的潜在影响，干旱和盐胁迫下黄艾草的内源激素含量。干旱胁迫为45%持水量，盐胁迫以120mMNaCl给出。用不同的SiNP浓度进行种子引发：SiNP1（50mgL-1），SiNP2（100mgL-1），SiNP3（150mgL-1），SiNP4（200mgL-1），和SiNP5(250mgL-1)。两种应力都会对植物的分析参数产生有害影响。然而,在干旱和盐胁迫下，SiNP5使叶绿素和渗透压物质的积累增加了96％和110％，例如总蛋白。分别。SiNP5显著降低了氧化损伤，提高了SOD活性，CAT,POD,和APX10%，54%,104%,干旱和42%，75%,72%,和215%在盐胁迫下，分别。所有浓度的SiNPs都大大提高了不同植物激素对干旱和盐胁迫的反应水平，并增加了披碱草植物的耐受性。此外，SiNPs降低了披碱草中的Na并增加了K浓度，表明在盐度胁迫下盐离子积累的减少。总的来说,SiNPs的外源施用（种子引发/浸渍）大大增强了生理生化和代谢反应，导致对干旱和盐胁迫的耐受性增加。因此,这项研究可作为进一步探索SiNPs在分子和遗传水平上减轻牧草和相关植物非生物胁迫的影响的参考。
