Identification of flowering genes in strawberry, a perennial SD plantReportar como inadecuado

Identification of flowering genes in strawberry, a perennial SD plant - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

BMC Plant Biology

, 9:122

First Online: 28 September 2009Received: 10 December 2008Accepted: 28 September 2009


BackgroundWe are studying the regulation of flowering in perennial plants by using diploid wild strawberry Fragaria vesca L. as a model. Wild strawberry is a facultative short-day plant with an obligatory short-day requirement at temperatures above 15°C. At lower temperatures, however, flowering induction occurs irrespective of photoperiod. In addition to short-day genotypes, everbearing forms of wild strawberry are known. In -Baron Solemacher- recessive alleles of an unknown repressor, SEASONAL FLOWERING LOCUS SFL, are responsible for continuous flowering habit. Although flower induction has a central effect on the cropping potential, the molecular control of flowering in strawberries has not been studied and the genetic flowering pathways are still poorly understood. The comparison of everbearing and short-day genotypes of wild strawberry could facilitate our understanding of fundamental molecular mechanisms regulating perennial growth cycle in plants.

ResultsWe have searched homologs for 118 Arabidopsis flowering time genes from Fragaria by EST sequencing and bioinformatics analysis and identified 66 gene homologs that by sequence similarity, putatively correspond to genes of all known genetic flowering pathways. The expression analysis of 25 selected genes representing various flowering pathways did not reveal large differences between the everbearing and the short-day genotypes. However, putative floral identity and floral integrator genes AP1 and LFY were co-regulated during early floral development. AP1 mRNA was specifically accumulating in the shoot apices of the everbearing genotype, indicating its usability as a marker for floral initiation. Moreover, we showed that flowering induction in everbearing -Baron Solemacher- and -Hawaii-4- was inhibited by short-day and low temperature, in contrast to short-day genotypes.

ConclusionWe have shown that many central genetic components of the flowering pathways in Arabidopsis can be identified from strawberry. However, novel regulatory mechanisms exist, like SFL that functions as a switch between short-day-low temperature and long-day-high temperature flowering responses between the short-day genotype and the everbearing -Baron Solemacher-. The identification of putative flowering gene homologs and AP1 as potential marker gene for floral initiation will strongly facilitate the exploration of strawberry flowering pathways.

Electronic supplementary materialThe online version of this article doi:10.1186-1471-2229-9-122 contains supplementary material, which is available to authorized users.

Katriina Mouhu, Timo Hytönen contributed equally to this work.

Download fulltext PDF

Autor: Katriina Mouhu - Timo Hytönen - Kevin Folta - Marja Rantanen - Lars Paulin - Petri Auvinen - Paula Elomaa


Documentos relacionados