Flowering Without Vernalization in Winter Canola (Brassica napus): use of Virus-Induced Gene Silencing (VIGS) to accelerate genetic gain

Shorter breeding cycles and the opportunity for enhanced genetic gains, together with the study of the molecular basis of vernalization, are essential areas of research in plant biology. Several approaches have been employed to achieve gene silencing in plants, but none so far reported in canola (Brassica napus), and particularly to induce flowering without vernalization in true winter lines by using sense DNA sequences in virus-induced gene silencing (VIGS) vectors. The present research provides the methods to transiently down-regulate, by VIGS technology, vernalization genes in winter annuals, specifically the family of Flowering Locus C (FLC) genes in winter canola (BnFLC1 to BnFLC5). Down-regulation of the BnFLC genes allows winter annuals to flower without vernalization and consequently provides the means for enhanced genetic gains. The proposed silencing system can be used to down-regulate gene families, to determine gene function, and to induce flowering without vernalization in winter Brassica lines as well as in many important winter crops.