GENERAL AND SPECIFIC COMBINING ABILITY OF SUGAR CONTENT IN CORN LANDRACES

Abstract

Six open-pollinated corn (Zea mays L.) landraces outstanding for the quality of their sweet green ears, and their 15 direct crosses, were evaluated at two locations in Chiapas. General and specific combining ability for grain sugar content, measured in °Brix, as well as heterosis of their crosses was evaluated. It was found that only additive gene effects were significant (P ≤ 0.05). Thus this ear sweetness related trait could be improved in parental varieties having the largest general combining ability by using recurrent selec- tion methods that exploit the additive genetic variance. Parental varieties ‘Campechano’ and ‘Paloma’ had the highest values of GCA effects (0.781 and 0.581) and produced the sweetest green ears with 13.1 and 12.9 °Brix. All crosses showed low values of heterosis.