IDENTIFICATION OF MOLECULAR MARKERS LINKED TO EARLY FLOWERING IN Eucalyptus grandis

Flowering time is an important trait for tree breeding because it determines the speed of generation turnover and therefore the rapidity of genetic gains, and it is of particular interest in Eucalyptus species. In this work, we used simple sequence repeats (SSRs), random amplified polymorphic DNA (RAPD) analysis and specific markers for flowering to evaluate early flowering segregation in a full-sibling family of Eucalyptus grandis and to identify molecular markers associated with the control of flowering time. A cross between a normal flowering tree (wild-type) and early flowering tree resulted in 118 progeny with a 1:1 Mendelian segregation ratio for flowering time (χ2 = 0.5424, P > 0.05), which suggested the action of one main gene in a locus named Early flowering in Eucalyptus grandis (PFEg). The SSR marker EMBRA 02 was related to the QTL PFEg, and identified this region as a candidate for trait control. These maps may be used as the basis for a study in which can be inserted new markers in an attempt to find more loci related to early flowering characteristic on eucalyptus.