赤霉素对紫斑牡丹种子下胚轴萌发及其种皮和胚乳结构的影响  

Effect of Gibberellic Acid on Seed Hypocotyl Germination and Cell Structure of Seed Coat and Endosperm of Paeonia rockii

作　　者：张双羽 唐红[1] 何丽霞 ZHANG Shuangyu;TANG Hong;HE Lixia(College of Forestry,Gansu Agriculture University,Lanzhou 730070,China;Gansu Engineering Research of Peony,Lanzhou 730046,China)

机构地区：[1]甘肃农业大学林学院,兰州730070 [2]甘肃省牡丹工程研究中心,兰州730046

出　　处：《西北植物学报》2019年第12期2187-2196,共10页Acta Botanica Boreali-Occidentalia Sinica

基　　金：甘肃省牡丹工程研究中心项目(XZ20181120);甘肃省科技厅“甘肃省科技支撑计划项目”(1604NKCA053)

摘　　要：以紫斑牡丹种子为试验材料,考察不同浓度赤霉素(GA3)处理下种子生根情况,同时对其种皮纹饰进行了扫描电镜(SEM)观察,并对胚乳结构进行了荧光倒置显微镜、透射电镜(TEM)观察,以揭示GA3对紫斑牡丹种子下胚轴解除休眠过程中种子种皮、胚乳结构变化和生根的影响。结果表明:(1)GA3处理能够促进紫斑牡丹种子生根,以300 mg/L GA3处理的种子生根效果最好,与对照相比可提前14.66 d生根,生根率可达62.33%。(2)扫描电镜观察发现,紫斑牡丹种皮表面含有蜡质,种子萌发进程中蜡质明显不断增加,种皮表面网眼逐渐消失,种皮皱缩明显。(3)光学显微镜观察发现,GA3处理的紫斑牡丹种子胚乳细胞中含有较多淀粉体和蛋白体,并随着种子萌发进程逐渐积累,可为种子萌发提供足够的养分。(4)透射电镜观察发现,GA3处理的紫斑牡丹种子胚乳细胞内大分子营养物质不断降解,线粒体、内质网、高尔基体等细胞器相继出现,种子下胚轴休眠解除,细胞壁较薄后期消融,利于营养物质传送。研究认为,适宜浓度GA3处理可有效加快紫斑牡丹种皮结构的改变和胚乳细胞内物质代谢进程,促进种子萌发,且300 mg/L GA3处理紫斑牡丹种子24 h可以获得最好的生根效果。The study used seeds of Paeonia rockii treated with different concentrations of gibberellic acid(GA3) to investigate the effects of rooting. Meanwhile, the seed coat surface decoration of P. rockii was observed by scanning electron microscopy(SEM) and endosperm structure by fluorescence inversion microscopy and transmission electron microscopy(TEM). Our purpose is to investigate the effect of GA3 on the hypoderm of P. rockii seeds, the changes of seed coat and endosperm structure and effect of rooting during axle dormancy release.(1) GA3 treatment could effectively promote the rooting of P. rockii seeds. 300 mg/L GA3 treatment was the best to promote rooting with the highest rooting rates of 62.33% and made the first seed rooting time shorter 14.66 days than that of control treatment.(2) Scanning electron microscopy(SEM) showed that the seed coat of P. rockii contained wax. During seed maturation, the wax content increased obviously, the mesh on the seed coat surface disappeared gradually, and the seed coat shrank obviously.(3) The results of optical microscopy showed that the endosperm cells of P. rockii seeds with GA3 treatment contained more amyloid and proteasome, which accumulated gradually during seed germination and provided enough nutrients for seed germination.(4) Transmission electron microscopy(TEM) showed that seeds with GA3 treatment macromolecule nutrients in the endosperm gradually decomposed, mitochondria, endoplasmic reticulum, golgi apparatus appeared, and its hypocotyl dormancy was broken and cell wall was thinner and ablated later, which was conducive to nutrient transport. It can be seen that GA3 treatment can effectively accelerate the change of seed coat structure and endosperm cell metabolism, and promote seed germination. 300 mg/L GA3 treatment for 24 hours can perform the best rooting efficiency.

关 键 词：紫斑牡丹 赤霉素 种子生根 种皮纹饰 胚乳细胞结构 

分 类 号：Q944.59[生物学—植物学] Q248