EVALUATION OF THE GENERAL AND SPECIFIC COMBINATORY FITNESS OF THE BASIC LINES OF EL BAJIO IN ITS DIFFERENT INCREMENTS FOR THEIR MAINTENANCE

Abstract

From a study of the characteristics of specific and general combining ability for yield, as well as for some morphological and physiological ones from difíerent sources of multiplication of twelve inbred lines of corn for El Bajío region, the following conclusions were reached: 1) There are statistically significant differences for the characteristic of combining ability between sources of soml' of the lines studied; 2) There is nor a defined tendency towards defini­te changes, only small fluctuations that can be interpreted either as due to sample size during the formation of the test crosses or to the multiplication of seed and its effect in the fluctuations of the genic" and genotypic frecuencies; 3) Changes in variation observed in the morphological and physiological characteristics can be due human selection; and in the particular case of two lines in which there were notable changes in earliness and coloration, it could also be and effect of the gametic selection operating in the differente environments where the lines were increased.