低温胁迫下甘蓝型冬油菜抗寒性与叶片激素含量的关联性

Association between cold resistance and leaf hormone content of Brassica napus L.under low temperature stress

为探究不同抗寒性甘蓝型冬油菜在应对低温胁迫时内源激素含量的变化,并阐明其抗寒性与叶片激素含量的关联性,选用感温性差异较大的4个甘蓝型冬油菜品种(品系),分别于4℃及0℃处理不同时间后测定植株叶片内玉米素(Zeatin,ZT)、赤霉素(Gibberellin A_(3),GA_(3))、水杨酸(Salicylic acid,SA)、生长素(Indole-3-acetic acid,IAA)和脱落酸(Abscisic acid,ABA)5种内源激素的含量,并联系抗寒性评价指标进行相关性分析。结果表明,与对照(24℃)相比,低温处理后甘蓝型冬油菜叶片中IAA、ZT、GA_(3)含量显著降低,ABA含量较对照(24℃)上升2~3倍,不同品种(品系)SA含量增幅差异较大。相关性分析结果表明,ABA、IAA、GA_(3)、SA含量的耐寒系数与抗寒性呈显著负相关。总之,内源激素含量会随外界温度变化而变化,且强抗寒性甘蓝型冬油菜品种(品系)叶片中激素含量的变化(上升或下降)幅度小于弱抗寒性品种(品系)。

To study the changes of endogenous plant hormone content in Brassica napus L.varieties(strains)with different cold resistance under low temperature stress,and to clarify the correlation between their cold resistance and leaf hormone content,four B.napus L.varieties(strains)with great difference in temperature sensitivity were selected and were treated at 4℃,0℃for different times,respectively.Then contents of five endogenous hormones in the leaves of the plants were detected,such as zeatin(ZT),gibberellin A_(3)(GA_(3)),salicylic acid(SA),indole-3-acetic acid(IAA)and abscisic acid(ABA),and correlation analysis was made with evaluation indexes of cold resistance.The results showed that,compared with the control(24℃),contents of IAA,ZT and GA_(3)in leaves of B.napus L.decreased significantly after low temperature treatment,and content of ABA increased by two to three times.The increase amplitude of SA content in different varieties(strains)of B.napus L.was different.Results of correlation analysis showed that,the cold resistance coefficients of ABA,IAA,GA_(3)and SA contents were significantly negatively correlated with cold resistance.In conclusion,the endogenous hormone content changes with the change of external temperature,and the change(increase or decrease)of hormone content in leaves of B.napus L.varieties(strains)with strong cold resistance was less than that of varieties(strains)with weak cold resistance.