Mapeamento de QTL para produção de grãos e caracters de planta em milho tropical utilizando marcadores microssatelites / Mapping QTL for grain yield and plant traits using microsatellite markers in a tropical maize population

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

Most of important agricultural and economical traits in maize are under the control of several gene loci, named quantitative trait loci (QTL). The possibility of using molecular markers and the statistic-genetic models made possible the mapping of these gene loci that affect such traits. Little focus has been given to QTL mapping study in populations derived from tropical maize germplasm, which has a broad genetic base with greater variability than temperate maize germplasm. Also, not much is known about the interaction of QTL in various environments (QTL X E). Two-hundred and fifty-six F2:3 progenies, derived from a crossing between two tropical maize inbred lines, were evaluated in five environments. The genetic map was developed with 139 microsatellite markers, using the software MAPMAKER/EXP version 3.0b. The analyses of QTL mapping and the detection of QTL X E interaction were performed using the Windows QTL-Cartographer version 2.5, JZmapQTL procedure, which is based on multiple-environment joint analysis (mCIM). The genetic map spanned 1,858.61 cM in length with an internal average of 13.47 cM between markers. Sixteen QTL were mapped for grain yield, eight for ears per plant, six for plant lodging, six for plant height, nine for ear height and two for number of leaves. The genetic effects of the mapped QTL presented varied signal and magnitude, displaying that each QTL contributes in a particular way for trait expression. Most of these QTL displayed gene action overdominance, many of them with significant QTL X E interaction detected. These results provide data for a better comprehension of genetic architecture on tropical maize genome. This information can be used in the marker-breeding selection of this species, leading more efficiency to Brazilian breeding programs

ASSUNTO(S)

microssatelites (genetica) microsatellites (genetics) mapeamento de qtl corn milho qtl analysis genetica vegetal plant genetics

ACESSO AO ARTIGO

Documentos Relacionados