title: Toward positional cloning of Vgt1, a QTL controlling the transition from the vegetative to the reproductive phase in maize.
abstract: Vgt1 (Vegetative to generative transition 1) is a quantitative trait locus (QTL) for flowering time in maize (Zea mays L.). Vgt1 was initially mapped in a ca. 5-cM interval on chromosome bin 8.05, using a set of near-isogenic lines (NILs) in the genetic background of the late dent line N28, with the earliness allele introgressed from the early variety Gaspé Flint. A new large mapping population was produced by crossing N28 and one early NIL with a ca. 6-cM long Gaspé Flint introgression at the Vgt1 region. Using PCR-based assays at markers flanking Vgt1, 69 segmental NILs homozygous for independent crossovers near the QTL were developed. When the NILs were tested in replicated field trials for days to pollen shed (DPS) and plant node number (ND), the QTL followed a Mendelian segregation. Using bulk segregant analysis and AFLP profiling, 17 AFLP markers linked to the QTL region were identified. Statistical analysis indicated a substantial coincidence of the effects of Vgt1 on both DPS and ND. Vgt1 was mapped at ca. 0.3 cM from an AFLP marker. As compared to DPS, the higher heritability of ND allowed for a more accurate assessment of the effects of Vgt1. The feasibility of the positional cloning of Vgt1 is discussed.
authors: Department of Agroenvironmental Science and Technology, University of Bologna, Italy.
authors: Silvio
authors: S
authors: Salvi
authors: Roberto
authors: R
authors: Tuberosa
authors: Elena
authors: E
authors: Chiapparino
authors: Marco
authors: M
authors: Maccaferri
authors: Stanislas
authors: S
authors: Veillet
authors: Leon
authors: L
authors: van Beuningen
authors: Peter
authors: P
authors: Isaac
authors: Keith
authors: K
authors: Edwards
authors: Ronald L
authors: RL
authors: Phillips
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular / Q000379:methods*; D018744:DNA, Plant / Q000235:genetics; D017343:Genes, Plant / Q000235:genetics; D005819:Genetic Markers; D005838:Genotype; D006720:Homozygote; D008969:Molecular Sequence Data; D010641:Phenotype; D011110:Polymorphism, Genetic; D019655:Quantitative Trait, Heritable; D012098:Reproduction / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D003313:Zea mays / Q000235:genetics* / Q000254:growth & development
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers