AUTHOR=Wang Yanli , Severing Edouard I. , Koornneef Maarten , Aarts Mark G. M. 

TITLE=FLC and SVP Are Key Regulators of Flowering Time in the Biennial/Perennial Species Noccaea caerulescens

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.582577

DOI=10.3389/fpls.2020.582577

ISSN=1664-462X

ABSTRACT=<p>The appropriate timing of flowering is crucial for plant reproductive success. Studies of the molecular mechanism of flower induction in the model plant <italic>Arabidopsis thaliana</italic> showed long days and vernalization as major environmental promotive factors. <italic>Noccaea caerulescens</italic> has an obligate vernalization requirement that has not been studied at the molecular genetics level. Here, we characterize the vernalization requirement and response of four geographically diverse biennial/perennial <italic>N. caerulescens</italic> accessions: Ganges (GA), Lellingen (LE), La Calamine (LC), and St. Felix de Pallières (SF). Differences in vernalization responsiveness among accessions suggest that natural variation for this trait exists within <italic>N. caerulescens</italic>. Mutants which fully abolish the vernalization requirement were identified and were shown to contain mutations in the <italic>FLOWERING LOCUS C</italic> (<italic>NcFLC)</italic> and <italic>SHORT VEGETATIVE PHASE</italic> (<italic>NcSVP)</italic> genes, two key floral repressors in this species. At high temperatures, the non-vernalization requiring <italic>flc-1</italic> mutant reverts from flowering to vegetative growth, which is accompanied with a reduced expression of <italic>LFY</italic> and <italic>AP1</italic>. This suggested there is “crosstalk” between vernalization and ambient temperature, which might be a strategy to cope with fluctuations in temperature or adopt a more perennial flowering attitude and thus facilitate a flexible evolutionary response to the changing environment across the species range.</p>