椤木石楠种子萌发过程中营养物质及内源激素变化的研究

Study on Changes of Nutrients and Endogenous Hormones During Seed Germination of Photinia davidsoniae

以椤木石楠种子为研究对象,对椤木石楠种子萌发过程中不同阶段种子的淀粉、还原糖、可溶性糖和可溶性蛋白以及内源激素(ABA、GA_(3)、IAA、MEIAA)共8个指标进行测定分析,探索椤木石楠种子萌发过程的生理变化。结果表明,椤木石楠种子的萌发方式为子叶出土型,根据形态变化特征,将其分为未萌发期(0 d)、露白期(1~5 d)、胚根生长期(6~10 d)、子叶生长期(11~15 d)共4个时期。在种子萌发过程中,淀粉、可溶性糖、可溶性蛋白、ABA、GA_(3)、IAA和MEIAA含量总体呈下降趋势,还原糖、GA_(3)/ABA和IAA/ABA含量先升后降。种子的萌发天数与淀粉、还原糖、可溶性糖、可溶性蛋白、ABA、GA_(3)、IAA和MEIAA含量都呈显著负相关。椤木石楠种子萌发过程是一个动态耗能过程,受GA_(3)/ABA的正向调控和IAA、MEIAA的负向调控。

Taking the seeds of Photinia davidsoniae as the research object,8 indexes of starch,reducing sugar,soluble sugar,soluble protein and endogenous hormones(ABA,GA_(3),IAA,MEIAA)in different stages of Photinia davidsoniae seed germination were determined and analyzed to explore the physiological changes of Photinia davidsoniae seed germination.The results showed that the seed germination mode of Photinia davidsoniae was cotyledone-exfoliated type.According to the morphological characteristics,the seeds were divided into four stages:non-germination stage(0 days),dewing-white stage(1-5 days),radicle growth stage(6-10 days)and cotyledon growth stage(11-15 days).During seed germination,the contents of starch,soluble sugar,soluble protein,ABA,GA_(3),IAA and MEIAA generally decreased,while the contents of reducing sugar,GA_(3)/ABA and IAA/ABA first increased and then decreased.The germination days of seeds were negatively correlated with the contents of starch,reducing sugar,soluble sugar,soluble protein,ABA,GA_(3),IAA and MEIAA.The seed germination process of Photinia davidsoniae was a dynamic energy-consuming process,which was positively regulated by GA_(3)/ABA and negatively regulated by IAA and MEIAA.