Efectos de aptitud combinatoria para vigor de plántula bajo estrés hídrico en maíz

early vigor is an essential component of crop plant development under most environmental conditions. nevertheless, little is known about the genetic control of characters in relation to seedling vigor in maize. the objective of this work was to estimate combining ability effects for characters in relation to seedling vigor in maize under water stress. six maize inbred lines under drought stress, three with high germination percentage, and three with low germination percentage, were crossed to obtain 15 single crosses. crosses were evaluated under controlled laboratory conditions in polyethylene glycol 8000 solution (1.4 mpa). data of the following characters were recorded: germination percentage under drought, coleoptile length, root length, root number and root radius. the general combining ability (gca) and specific combining ability (sca) information on crosses were obtained by using the method 4, griffing's model i analysis. inbred lines 31b and p004 showed the highest gca estimates for the variables evaluated. the characters related to seedling vigor under drought stress were mainly controlled by additive gene effects, although non-additive effects have also shown to be important, especially for coleoptile length.