PDF(Pubmed)
Abstract：
Polyethylene glycol can abrogate plant seed dormancy and alleviate salt-alkali stress damage to plants, but its role in embryonic dormancy abrogation and germination in Sorbus pohuashanensis is not yet clear. The mechanism by which polyethylene glycol promotes the release of embryonic dormancy may be related to the synthesis and metabolism of endogenous hormones, reactive oxygen species and reactive nitrogen. In this article, germination in indoor culture dishes was used, and the most suitable conditions for treating S. pohuashanensis embryos, with polyethylene glycol (PEG) and sodium carbonate (Na2CO3), were selected. Germination was observed and recorded, and related physiological indicators such as endogenous hormones, reactive oxygen species and reactive nitrogen were measured and analyzed to elucidate the mechanism of polyethylene glycol in alleviating salt-alkali stress in S. pohuashanensis embryos. The results showed that soaking seeds in 5% PEG for 5 days is the best condition to promote germination, which can increase the germination rate of embryos under salt-alkali stress by 1-2 times and improve indicators such as germination speed and the germination index. Polyethylene glycol led to an increase in gibberellin (GA), indole-3-acetic acid (IAA), ethylene (ETH), cytokinin (CTK), nitric oxide (NO), soluble protein and soluble sugar in the embryos under salt-alkali stress; increased activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), nitrate reductase (NR) and nitric oxide synthase (NOS) in the embryos; a reduction in the accumulation of abscisic acid (ABA), hydrogen peroxide (H2O2) and malondialdehyde (MDA). Therefore, it is suggested that the inhibitory effect of polyethylene glycol on the salt-alkali-stress-induced germination of S. pohuashanensis embryos is closely related to the response of endogenous hormones, reactive oxygen species and nitric oxide signalling.
摘要：
聚乙二醇可以消除植物种子休眠,缓解盐碱胁迫对植物的伤害,但其在花花草胚芽休眠和萌发中的作用尚不清楚。聚乙二醇促进胚胎休眠释放的机制可能与内源性激素的合成和代谢有关。活性氧和活性氮。在这篇文章中,在室内培养皿中使用发芽，和最适合的条件，处理斑潜鱼胚胎，与聚乙二醇（PEG）和碳酸钠（Na2CO3），被选中。观察并记录发芽情况,和相关的生理指标，如内源性激素，通过对活性氧和活性氮的测定和分析,阐明了聚乙二醇在减轻盐碱胁迫中的作用机制。结果表明,在5%PEG中浸种5天是促进种子萌发的最佳条件,可提高盐碱胁迫下胚的发芽率1-2倍,提高发芽速度和发芽指数等指标。聚乙二醇导致赤霉素（GA）的增加，吲哚-3-乙酸(IAA),乙烯（ETH），细胞分裂素(CTK),一氧化氮（NO），盐碱胁迫下胚胎的可溶性蛋白质和可溶性糖；超氧化物歧化酶（SOD）活性增加，过氧化物酶(POD),过氧化氢酶(CAT),胚胎中的硝酸还原酶（NR）和一氧化氮合酶（NOS）；降低脱落酸（ABA）的积累，过氧化氢(H2O2)和丙二醛(MDA)。因此,提示聚乙二醇对盐碱胁迫诱导的火药树胚萌发的抑制作用与内源激素的反应密切相关,活性氧和一氧化氮信号。
