柳枝稷体外诱导花器官逆转与非逆转穗芽生理特性差异研究  

Physiological Characteristic Diversity in Reversed and Non-Reversed Spike Buds of Switchgrass

作　　者：王勇锋[1] 李毛[1] 崔桂宾[1] 徐开杰 孙风丽[1] 张超[1] 刘曙东[1] 奚亚军[1] 

机构地区：[1]西北农林科技大学农学院,陕西杨凌712100 [2]中国农业科学院棉花研究所,河南安阳455000

出　　处：《草地学报》2017年第4期768-776,共9页Acta Agrestia Sinica

基　　金：国家自然科学基金(31171607;31371690)资助

摘　　要：柳枝稷(Panicum virgatum L.)是一种短日照开花作物,具有适应性广和生物质产量高等特点,在国际上被广泛认定为模式能源植物。前期研究发现带有1~2cm长幼穗的柳枝稷茎端组织在穗芽诱导培养基上培养能够通过花器官逆向发育(生殖生长转向营养生长)形成大量再生芽,称为逆转穗芽,而在MS基本培养基上只能通过腋芽形成少量再生芽,称为非逆转穗芽。为探索柳枝稷逆转穗芽形成机制,对逆转穗芽和非逆转穗芽进行了生理学差异研究。结果发现:柳枝稷逆转穗芽具有更高的总糖含量和更高的氮利用效率,但叶绿素含量却较低;逆转穗芽具有更强的抗氧化酶系统(SOD,POD,CAT,PPO);外源施加细胞分裂素对柳枝稷内源玉米素的合成无显著影响,但对内源吲哚乙酸的合成起到一定的抑制作用,而低水平的吲哚乙酸可能是逆转穗芽诱导起始的关键;脱落酸在逆转穗芽发育的后期阶段起到重要的作用,而赤霉素在其发育的整个时期都行使重要的功能。Swithchgrass（Panicum virgatum L.）is a short-day plant.Due to its wide adaptability and high biomass yield,switchgrass was regarded as the model biofuel plant world widely.Previous study on switchgrass showed that the shoot apexes of tillers at elongation stage 4,which harboring a spike 1~2 cm long,incubated on shoot induction medium would induce flower reversion and finally formed massive regeneration buds,named as reversed spike buds.Correspondingly,shoot apexes incubated on the MS basal medium showed no flower reverse and finally formed little buds,named non-reversed spike buds.To discover the underlying mechanism of the reversed spike bud formation,some physiological indexes of the reversed spike buds and non-reversed spike buds were compared.The results showed that the reversed spike buds had higher sugar content but lower chlorophyll content,and they were more effective in nitrogen utilization;the activity of antioxidant enzyme system（SOD,POD,CAT,PPO）were higher;the exogenous supplementary of cytokinin exhibited little effect on endogenous cytokinin zeatin,however it suppressed the endogenous indoleacetic acid to some extent,which might play an important role in spike buds initiation.Abscisic acid affected spike buds development at the late stage while gibberellin affected spike buds development throughout the whole process.

关 键 词：柳枝稷 花逆转 生殖生长 营养生长 激素 生理特性 

分 类 号：Q945.45[生物学—植物学] S578[农业科学—作物学]