Variabilidade de genótipos de milho quanto à composição de carotenoides nos grãos

Abstract

The objective of this work was to characterize 134 maize (Zea mays) genotypes, for carotenoids content and build a genetic profile to facilitate future breeding to increase grain nutritional value (biofortification). Seeds came from experimental fields and from the Banco Ativo de Germoplasma of Embrapa Milho e Sorgo, Sete Lagoas, MG, Brazil. The genotypes were co mmercial hybrids, varieties, and inbred lines developed by the Embrapa biofortification program and other accessions, chosen for their yellow-orange endosperm color. Total grain carotenoids, carotenes, xanthophylls (monohydroxylates and dihydroxylates) were determined by chromatographic-spectrophotometric methods. The detected averages were: 22.34μ gg-1 for total carotenoids, 2.55μ gg-1 for carotenes, 3.86μ gg-1 for monohydroxylated xanthophylls, and 15.93μ gg-1 for dihydroxylated xanthophylls. The genotypes variability was divided into 18 groups by the method of Tocher. The Embrapa germplasm has variability and potential for development of maize lines biofortified for total of provitamin A carotenoids. © 2009 Embrapa Informação Tecnológica.