花瓣形态建成关系到观赏花卉的品质形成，而花瓣的生长是花瓣形态建成的基础，植物激素通过互作网络参与花瓣的生长毋容置疑。本项目组前期研究发现，赤霉素（GA）与脱落酸（ABA）拮抗调控非洲菊花瓣生长；GA和ABA处理后2小时有9个拮抗调控的差异表达转录因子。在此基础上，本研究将首先检测两种激素处理后这些转录因子基因的时空表达并进行拟南芥的异源转化，初步筛选出参与两种激素拮抗调控细胞伸展的重要候选转录因子1-2个；进一步采用VIGS技术，在非洲菊舌花花瓣中瞬时沉默候选转录因子基因以及超表达获得非洲菊转基因植株(突变体)，进行与花瓣以及细胞伸展相关的表型分析，最终结合表达谱的分析以及突变体中下游生长相关基因的表达分析，初步勾画出GA和ABA拮抗调控非洲菊花瓣伸展的分子信号网络。本研究为最终阐明花瓣形态建成的分子调控网络奠定基础，同时为花卉分子育种提供理论依据和基因资源。

Petal is one of the most important characters in quality formation of ornamental flowers. Petal growth is pivotal in petal morphogenesis but its molecular regulation mechanism is still unclear. It is undoubtedly that plant hormones are involved in the regulation of petal growth. Our preliminary works show that gibberellic acid (GA) and abscisic acid (ABA) antagonistic regulated petal growth in Gerbera hybrida. Nine transcrition factors (tfs) of differential expression have been obtained and they were up-regulated or down-regulated 2h after ABA or GA treatments, respectively. In this study, the screening of transcrition factor candidates (one to two) will be carried out firstly among 9 tfs by the detection of gene expression patterns temporally and spatially and by the ectopic transformation of the candidate genes in Arabidopsis. Functional characterization then will be further verified via overexpression of the candidate genes in Gerbera and virus-induced gene silencing (VIGS) will be emplyed for the loss-of-functional genetic evidences in Gebera petal. Finally,by the combination of the phenotypic analysis and expression profile analysis of the putative downstream structure genes in transgenic mutants,the prilimitary molecular mechanisms involved in petal expansion and particularly the antagonism between GA and ABA will be propased in Gerbera hybrida. This research will contribute to the molecular regulation network of petal morphogenesis and provide the theoretical basis and gene resources for the flower molecular breeding.