Investigating the potential use of virus technology to further our understanding of floral induction and its application in plant breeding programmes

• Main Author: Akande, Femi David
• Published: University of Warwick 2014
• Subjects: 570; SB Plant culture
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.632910

Flowering Locus T (FT ) plays a pivotal role in floral induction. It integrates the inputs from a complex network of flowering signalling pathways. Flowering is an efficiently orchestrated event that occurs in a plant at a particular time to ensure maximum reproductive success. It has been suggested that the FT protein is a long- distance mobile floral stimulus. In this report studies with a mutant version of FT (mFT) which had the start codon replaced with a stop codon to generate a non-translatable FT indicated that the mRNA was also capable of long distance movement although its physiological function as a floral stimulus was inhibited. Gene function study of FT and FT orthologues on brassica, tobacco, tomato and potato using the plant virus expression vector Potato Virus X (PVX) generated some interesting findings. In Short day Maryland Mammoth tobacco plants the overexpression of the Arabidopsis FT under non-inductive Long day condition induced early flowering while the mFT and mock control remained in the vegetative stage. In short day potato, it did not seem to have an effect on tuberization as only one from five of the inoculated plants tuberized. In brassica (broccoli) the effect on flowering time was inhibited due to Virus-induced Gene Silencing (VIGS) but the tomato FT (SP6A) had an effect on flowering time. In tomato, the overexpression of the Arabidopsis FT and FT- orthologues from tomato induced early flowering but the difference in flowering time in comparison to the controls was only a few days. Phenotypical and morphological changes such as seed production and lateral side shoot development were caused by expression of the target genes. The exact mechanism of action of these genes in the control of seed production and lateral side shoot development is unclear.