Resumen de Combinig ability effects for seed vigour traits related to emergence at low temperature in maize and grain sorghum

P. Gracia, José Manuel Lasa Dolhagaray, A. Álvarez, A. García

• Seed vigour traits correlated with field emergence speed in cool conditions and with acceptable coefficients of variation were determined in hybrids and selfs from public inbred lines of maize and grain sorghum. Controlled tests showed less environmental variation than field measurements. In maize, there were significant parental effects in all traits except mean time to field emergence in cool conditions (FEI). Germination percentage after 12 days at 10 grades C. alone (LT) or related to a 25 grades C control (LTC), and FEI, showed hybrid vigour. In LT, LTC and FEI, EZ18o2 and CM105 were the lines with the highest general combining ability (GCA) effects. No trait showed significant mean heterosis in sorghum, where Ks22 was the line with highest GCA in LTC, LT and FEI. Maize gennination Lit at low temperatures was better than that of sorghum, and its field emergence in cool conditions was , so higher and faster.