Biologie du Fruit et Pathologie, UMR 1332, Université Bordeaux, INRAE, Villenave d'Ornon, F-33140, France.
Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, 60131, Italy.
New Phytol. 2021 Oct;232(1):372-387. doi: 10.1111/nph.17557. Epub 2021 Jul 16.
Plant architecture is central in determining crop yield. In the short-day species strawberry, a crop vegetatively propagated by daughter-plants produced by stolons, fruit yield is further dependent on the trade-off between sexual reproduction (fruits) and asexual reproduction (daughter-plants). Both are largely dependent on meristem identity, which establishes the development of branches, stolons and inflorescences. Floral initiation and plant architecture are modulated by the balance between two related proteins, FLOWERING LOCUS T (FT) and TERMINAL FLOWER 1 (TFL1). We explored in woodland strawberry the role of the uncharacterised FveFT2 and FveFT3 genes and of the floral repressor FveTFL1 through gene expression analyses, grafting and genetic transformation (overexpression and gene editing). We demonstrate the unusual properties of these genes. FveFT2 is a nonphotoperiodic florigen permitting short-day (SD) flowering and FveTFL1 is the long-hypothesised long-day systemic antiflorigen that contributes, together with FveFT2, to the photoperiodic regulation of flowering. We additionally show that FveFT3 is not a florigen but promotes plant branching when overexpressed, that is likely to be through changing axillary meristem fate, therefore resulting in a 3.5-fold increase in fruit yield at the expense of stolons. We show that our findings can be translated into improvement of cultivated strawberry in which FveFT2 overexpression significantly accelerates flowering.
植物结构是决定作物产量的核心。在短日照草莓中,匍匐茎上产生的子株进行营养繁殖,其果实产量还取决于有性生殖(果实)和无性生殖(子株)之间的权衡。这两者在很大程度上取决于分生组织的身份,它决定了枝条、匍匐茎和花序的发育。花的起始和植物结构由两种相关蛋白,即开花位点 T(FT)和末端花 1(TFL1)之间的平衡来调节。我们通过基因表达分析、嫁接和遗传转化(过表达和基因编辑)研究了林地草莓中未鉴定的 FveFT2 和 FveFT3 基因以及花抑制因子 FveTFL1 的作用。我们证明了这些基因的不寻常特性。FveFT2 是一种非光周期成花素,允许短日照(SD)开花,而 FveTFL1 是长日假说中的长日系统抗花素,它与 FveFT2 一起参与开花的光周期调节。我们还表明,FveFT3 不是成花素,但当过表达时会促进植物分枝,这可能是通过改变腋芽分生组织的命运,从而导致果实产量增加 3.5 倍,而匍匐茎减少。我们的研究结果表明,我们的发现可以转化为栽培草莓的改良,其中 FveFT2 的过表达显著加速了开花。