干旱胁迫下外源冠菌素对玉米幼苗生长和内源激素含量的影响

Effect of Exogenous Coronatine on Contents of Endogenous Hormones in Maize Seedling under Drought Stress

采用PEG-6000模拟干旱研究植物生长调节物质冠菌素(COR)在干旱条件下对玉米幼苗生长及内源激素系统的影响,结果表明:干旱处理8d,与PEG处理相比,COR+PEG处理显著提高玉米幼苗的株高、根长、根条数和根冠比;在正常情况下,COR能诱导茉莉酸甲酯(MeJA)的增加;干旱条件下COR处理的幼苗叶片和根中ABA和MeJA的同时显著升高;COR处理的玉米幼苗叶片和根中GA3含量在干旱第2天和第3天与MeJA含量同时显著增加;干旱胁迫第2天,COR处理中的IAA和ZR含量在叶片同时降低,而在根中则同时升高,至干旱第3天,其ZR含量在叶中降低,而在根中则增加。初步认为,干旱胁迫下,冠菌素可通过调节玉米幼苗体内的激素系统平衡以诱导其形态改变,并增强其抵抗逆境的能力。

PEG-6000 was used to simulate drought stress to investigate effects of plant growth regulator coronatine on endogenous hormones system under drought stress. The results showed that coronatine improved significantly plant height, length of root, root number and root/shoot ratio during 8 days of drought. The content of ABA and MeJA in leaves and roots synchronously increased after coroantine application under drought stress. On the 2nd and the 3rd day after drought, GA3 and MeJA also simultaneously increased by coronatine. On the 2nd day after drought, the concent of IAA and ZR increased in leaves and decreased in roots after coronatine application. And on the 3rd day after drought, ZR also maintained the same trend as 2nd day. Our primary conclusion was that coronatine could induce maize seedlings to resist the stress by regulating the balance of endogenous hormones under drought stress and then leading to the changes of configuration.