外源GA3对葡萄花序伸长及赤霉素合成代谢相关基因表达的影响  

Effects of Exogenous GA3 on Inflorescence Elongation and Gibberellin Anabolism Related Gene Expression in Grapevine

作　　者：杨丽丽[1] 牛早柱 魏建国[1] 赵艳卓[1] 陈展[1] 宣立锋[1] 褚凤杰[1] Yang Lili;Niu Zaozhu;Wei Jianguo;Zhao Yanzhuo;Chen Zhan;Xuan Lifeng;Chu Fengjie(Shijiazhuang Institute of Fruit Trees Hebei Academy of Agricultural and Forestry,Shijiazhuang,050061)

机构地区：[1]河北省农林科学院石家庄果树研究所,石家庄050061

出　　处：《分子植物育种》2020年第17期5600-5606,共7页Molecular Plant Breeding

基　　金：国家重点研发计划(2018YFD0201307);河北省农林科学院创新工程项目共同资助。

摘　　要：本研究以阳光玫瑰葡萄为试材,盛花前1周使用外源GA3处理花序,发现10 mg/L、25 mg/L、50 mg/L、100 mg/L GA3均可显著促进花序的伸长,且花序伸长长度与赤霉素浓度正相关。试验进一步用液相色谱检测了不同时期穗轴中GA3的含量,发现外源GA3可以短时间内提高幼嫩穗轴中GA3水平,在处理24 h时GA3水平达到顶峰,且100 mg/L GA3处理峰值最大,2 d时GA3水平迅速回落。通过荧光定量PCR检测了编码赤霉素生物合成过程中第一阶段的关键酶CPS和第三阶段无活性赤霉素转化为活性赤霉素的关键酶GA20ox和GA3ox的基因,结果显示这三个关键酶的基因呈下调表达,且GA3处理浓度越高,基因表达水平越低。赤霉素代谢途径上编码负调控蛋白DELLA的基因与对照相比整体呈下调表达,且外源GA3浓度越高,DELLA基因表达量越低。说明外源活性赤霉素GA3严重抑制了内源赤霉素合成途径上关键基因的表达,间接抑制了内源赤霉素的合成;同时抑制了代谢通路上负调控DELLA基因的表达,促进花序的伸长。Seven days before flowering,the inflorescences of Shine Muscat grape were treated with different concentration of gibberellin(GA3)to understand the mechanism of inflorescence elongation.It was found that 10 mg/L,25 mg/L,50 mg/L and 100 mg/L GA3 could significantly promote the elongation of inflorescence,and the length was positively correlated with the concentration of GA3.The content of GA3 in inflorescence peels in different periods were detected by liquid chromatography.It was found that the content of GA3 of young inflorescence peels elevated during a short time,and reached the peak at 24 h after treatment,and quickly fell back at 2 d.Genes coding three key enzyme including CPS,GA20ox and GA3ox,were detected by qRT-PCR in gibberellin synthesis pathway.The results showed that the genes coding these three key enzymes were down-regulated,and the higher the treatment concentration,the lower the genes expression level.However,the negative regulatory protein DELLA gene in gibberellin metabolic pathway was down-regulated as a whole compared with the control group,and the higher the exogenous GA3 concentration was,the lower DELLA expression was.The DELLA expression was the lowest in the peduncle treated with 100 mg/L GA3.The results showed that exogenous GA3 inhibited the synthesis of endogenous gibberellin, regulated plant signal transduction of gibberellin, and promoted the elongation of inflorescence.

关 键 词：葡萄(Vitis vinifera) GA3 花序伸长 qRT-PCR 

分 类 号：S663.1[农业科学—果树学]