茉莉酸甲酯浸种对盐胁迫下谷子萌发的影响

Effects of Jasmonic Acid Seed Soaking on Millet Germination under Salt Stress

茉莉酸甲酯是一种能提高植物对逆境胁迫适应能力的植物生长调节剂,通过研究茉莉酸甲酯浸种对盐胁迫下谷子萌发的影响,探究其在谷子抗盐胁迫初期的作用及生理机制,可为盐胁迫提高谷子幼苗存活率提供理论依据。现选取现代品种晋谷21号为供试材料,用0.1μmol/L茉莉酸甲酯和150 mmol/L氯化钠处理种子,设置4个处理:水(CK),茉莉酸甲酯(MeJA),茉莉酸甲酯+氯化钠(MeJA+NaCl)和氯化钠(NaCl)。在培养第3天和第6天分别测定发芽率、芽长和根长,发芽结束后(第6天)测定脯氨酸、淀粉和可溶性糖的含量。结果表明:茉莉酸甲酯浸种可以提高盐胁迫下谷子的抗逆能力。盐胁迫显著降低了谷子发芽率(P<0.05),用0.1μmol/L茉莉酸甲酯浸种处理后,可以有效缓解盐胁迫导致的发芽率下降现象。同时,茉莉酸甲酯浸种后能有效提高盐胁迫下种子的可溶性糖含量和脯氨酸含量,提升盐胁迫下谷子的发芽率、根长和芽长。综上所述,外源茉莉酸甲酯通过提高萌发期谷子可溶性糖和脯氨酸的含量从而提高其抗盐能力。

Jasmonic acid is a plant growth regulator that can improve the ability of plants to adapt to adversity and stress.The effect of methyl jasmonate on millet germination under salt stress was studied to explore jasmonic acid’s role and physiological mechanism in the early stage of millet salt stress resistance,which would provide a theoretical basis for improving the survival rate of millet seedlings under salt stress.Jingu 21,a modern cultivar,was selected as the test material,and its seeds were treated with 0.1μmol/L of methyl jasmonate(MeJA)and 150 mmol/L of sodium chloride(NaCl),and four treatments were set,water(CK),MeJA,MeJA+NaCl,and NaCl.The germination rate,shoot length,and root length were measured on the 3 rd and 6 th day of culture.The contents of proline,starch,and soluble sugar were measured on the 6 th day after germination.The results showed that soaking seeds with exogenous jasmonic acid could improve the stress resistance of millet under salt stress.Salt stress significantly reduced the germination rate of millet(P<0.05).Seed soaking with 0.1μmol/L of methyl jasmonate could effectively alleviate the decline of germination rate caused by salt stress.Methyl jasmonate could effectively improve the soluble sugar and proline content of millet seeds under salt stress and improve the germination rate,root length,and bud length of millet under salt stress.In conclusion,exogenous methyl jasmonate could increase the soluble sugar and proline content to improve the salt tolerance of foxtail millet.