Seleção visual para endospermas de milho (Zea mays L) opaco-2 de diferentes fenótipos
Palavras-chave:
gene opaco-2, endosperma opaco, selecao visual, teores lisina, peso sementesResumo
Three phenotypic classes of seed were selected from the single cross hybrid AG 501 opaco-2' of maize with respect to the extent of the opaque and vitreous portions of the endosperm: (a) completely opaque, (b) ca. 75% opaque and 25% vitreous, and (c) ca. 50% opaque and 50% vitreous (modified opaque). A fourth class of seed, unselected, was used as control. The objective was to determine the effects of two cycles of selection on protein and lysine content, and on volume and weight of the progeny seed.
The results indicate that selection for modified opaque endosperm decreases lysine percent in the whole seed without affecting protein percent. Selecion for modified opaque endosperm does not substantially affect seed volume but increases seed weight.
Referências
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