干旱胁迫下茉莉酸甲酯对水稻叶片质膜透性及无机离子含量的影响

茉莉酸甲酯(MeJA)是植物体内一种具有应答外界刺激,传导逆境信号及启动抗逆基因的天然生理活性物质,提高作物的抗旱性是MeJA的重要生理功能之一。研究了干旱胁迫下施用不同浓度(250,2.5,0.25μmol/L)MeJA对水稻幼苗的生理调控作用。结果表明,干旱处理后水稻叶片水势和叶绿素含量显著下降,叶片MDA含量、电导率及无机离子(K+,Ca2+,Mg2+)含量均显著上升,而喷施不同浓度的MeJA则显著提高叶片水势和叶绿素含量,降低质膜透性和叶片无机离子含量,从而增强水稻幼苗的抗旱性。以0.25μmol/L MeJA处理抗旱效果最好,2.5μmol/L次之,然后是250μmol/L。

Effects of Methyl Jasmonate on Membrane Permeability and Inorganic Ions Content in Rice Leaves under Drought Stress

Methyl Jasmonate(MeJA)is an important naturally physiological substance that regulates the expression of plant defense genes in response to various environmental stress including drought.Different concentration of MeJA treatment(0 25,2 5 and 250 μmol/L) under drought stress were chosen to study its effect on physiological traits of rice seedlings.Under drought stress condition,leaf water potential and chlorophyll content were significantly decreased,whereas conductivity,the content of MDA and inorganic ions(K~+,Ca~(2+),Mg~(2+)) in rice leaves were significantly increased,these effects could be restrained after spraying various concentration of MeJA(250,2.5,0.25 μmol/L),which meant MeJA could increase drought resistance.There existed concentration effect,0.25 μmol/L MeJA had the best effect,2.5 μmol/L took second place,the third was 250 μmol/L.