INRA d'Angers Nantes, IFR 149 Quasav, UMR 1259 GenHort, Beaucouzé, France.
Theor Appl Genet. 2011 Mar;122(4):661-75. doi: 10.1007/s00122-010-1476-5. Epub 2010 Nov 3.
The pattern of development of the inflorescence is an important characteristic in ornamental plants, where the economic value is in the flower. The genetic determinism of inflorescence architecture is poorly understood, especially in woody perennial plants with long life cycles. Our objective was to study the genetic determinism of this characteristic in rose. The genetic architectures of 10 traits associated with the developmental timing and architecture of the inflorescence, and with flower production were investigated in a F(1) diploid garden rose population, based on intensive measurements of phenological and morphological traits in a field. There were substantial genetic variations in inflorescence development traits, with broad-sense heritabilities ranging from 0.82 to 0.93. Genotypic correlations were significant for most (87%) pairs of traits, suggesting either pleiotropy or tight linkage among loci. However, non-significant and low correlations between some pairs of traits revealed two independent developmental pathways controlling inflorescence architecture: (1) the production of inflorescence nodes increased the number of branches and the production of flowers; (2) internode elongation connected with frequent branching increased the number of branches and the production of flowers. QTL mapping identified six common QTL regions (cQTL) for inflorescence developmental traits. A QTL for flowering time and many inflorescence traits were mapped to the same cQTL. Several candidate genes that are known to control inflorescence developmental traits and gibberellin signaling in Arabidopsis thaliana were mapped in rose. Rose orthologues of FLOWERING LOCUS T (RoFT), TERMINAL FLOWER 1 (RoKSN), SPINDLY (RoSPINDLY), DELLA (RoDELLA), and SLEEPY (RoSLEEPY) co-localized with cQTL for relevant traits. This is the first report on the genetic basis of complex inflorescence developmental traits in rose.
花序的发育模式是观赏植物的一个重要特征，其经济价值在于花朵。然而，人们对花序结构的遗传决定因素知之甚少，特别是在具有长生命周期的木本多年生植物中。我们的目标是研究玫瑰中这一特征的遗传决定因素。在一个基于田间表型和形态特征的密集测量的 F1 二倍体花园玫瑰群体中，研究了与花序发育时间和结构以及花产量相关的 10 个性状的遗传结构。在花序发育性状方面存在显著的遗传变异，广义遗传力范围为 0.82 到 0.93。大多数（87%）性状对的基因型相关性显著，这表明在基因座之间存在多效性或紧密连锁。然而，一些性状对之间的非显著和低相关性表明，控制花序结构的有两个独立的发育途径：（1）花序节点的产生增加了分支的数量和花的产量；（2）与频繁分枝相关的节间伸长增加了分支的数量和花的产量。QTL 作图鉴定了 6 个花序发育性状的共同 QTL 区域（cQTL）。一个与开花时间和许多花序性状相关的 QTL 被定位到相同的 cQTL 上。在拟南芥中控制花序发育性状和赤霉素信号的几个候选基因被定位在玫瑰中。与相关性状的 cQTL 共定位的有控制开花时间的 RoFT、TERMINAL FLOWER 1 (RoKSN)、SPINDLY (RoSPINDLY)、DELLA (RoDELLA) 和 SLEEPY (RoSLEEPY) 的玫瑰同源物。这是关于玫瑰中复杂花序发育性状遗传基础的首次报道。
