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Characterization of South American exotic maize (Zea mays L.) populations with opaque phenotype

Cláudia T. Guimarães^I; Everaldo Gonçalves de Barros^I; Maria J. V. Vasconcelos^II; Edilson Paiva^II

^INúcleo de Biotecnologia Aplicada à Agropecuária (BIOAGRO), Universidade Federal de Viçosa (UFV), 36570-000 Viçosa, MG, Brasil. Send correspondence to E.G.B.
^IICentro Nacional de Pesquisa de Milho e Sorgo (CNPMS/EMBRAPA), 35701-970 Sete Lagoas, MG, Brasil

ABSTRACT

Eleven exotic populations of opaque maize from Brazil, Bolivia and Chile were characterized. Kernel density, lysine and tryptophan contents, total zeins and non-zeins, zcin individual fractions, and soluble sugars were analyzed. Although these populations bear soft endosperm, their zein profiles by gel electrophoresis, the nutritional quality of their proteins as well as the densities of their grains do not follow the patterns present in other opaque maize genotypes. We concluded that these exotic populations are not included in any class of endosperm mutant described so far.

Keywords: South American; exotic maize; Zea mays ; opaque phenotype.

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