胺鲜酯(DA-6)浸种对盐胁迫下白三叶种子萌发及抗盐性的影响

以白三叶(Trifolium repens L.‘Haifa’)为研究对象，研究了0.8 mmol·L^-1胺鲜酯(DA-6)浸种处理对白三叶种子在盐胁迫条件下萌发的影响，并对DA-6诱导的耐盐机理进行初步研究，为白三叶的栽培管理提供参考。结果表明，DA-6浸种显著提高了盐胁迫下种子的发芽势、发芽率、活力指数、发芽指数、茎长和鲜干重(P<0.05)。盐胁迫显著诱导了游离脯氨酸和可溶性糖的积累，降低了细胞渗透势(P<0.05)。此外，盐胁迫导致了萌发种子中活性氧(超氧阴离子和过氧化氢)和膜脂过氧化产物丙二醛含量显著增加，电导率显著升高(P<0.05)。DA-6浸种前处理显著提高了胁迫下抗氧化酶(SOD、POD和APX)的活性，增幅分别为33.0%、31.9%和49.1%,这有效地缓解了由盐胁迫引起的氧化损伤，有利于幼苗稳定细胞膜(P<0.05)。本研究表明DA-6浸种处理通过增强抗氧化防御并降低细胞氧化伤害，从而提高盐胁迫下白三叶种子的萌发特性和胁迫耐受性。

Effects of the Seed Soaking with DA-6 on Germination Characteristics and Stress Tolerance of White Clover under Salt Stress

Effects of 0.8 mmol·L^-1 diethyl aminoethyl hexanote (DA-6) treatment on seeds germination of white clover (Trifolium repens L. 'Haifa’) were investigated under salt stress. One hundred mmol·L^-1 NaCl was used as a salt stress treatment to provide a reference for the cultivation and management of turfgrass in urban greenery. Seeds soaking with DA-6 significantly increased the germination vigor,germination percentage,germination index,vitality index,stem length and fresh/dry weight of seedlings (P<0.05). Salt stress significantly induced the accumulation of free proline and soluble sugar,followed by a significantly lower cellular osmotic potential (P<0.05). However,pretreatment with DA-6 immersion under salt stress had no significant effect on the accumulation of free proline and soluble sugar in seedlings (P>0.05). In addition,salt stress led to a significant increase in the content of reactive oxygen species (superoxide anion and hydrogen peroxide),a membrane lipid peroxidation product malondialdehyde,and electrolyte leakage in seedlings (P<0.05). Our current study indicated that DA-6 soaking improved germination characteristics and stress tolerance of white clover seeds by enhancing antioxidant defense and reducing cellular oxidative damage under salt stress.