Caracterización molecular de líneas tropicales de maíz (Zea mays L.) y su relación con los patrones heteróticos

the germplasma diversity is important for the breeding programs. thirty five lines of white corn, belonging to danac foundation and three tester lines (cml-144, cml-254, and l20-2#1) of the tropical heterotic pattern eto x tuxpe？o were evaluated. thirteen ssr primer pairs distributed in ten chromosomes were used. the amplification of products allowed the construction of a data matrix of information to determine the genetic distance (gd=1-sg) using the jaccard's coefficient of genetics similarity (gs), to fulfill a dendrogram under the criterion of unweighted pair-group method with arithmetical averages (upgma) and perform a principal components analysis (pca). the heterosis (h=sab-0.5 (la+lb)) was determined using yield information of the lines and hybrids. the polymorphic ssr amplified 25 bands in the lines, with an average of 2.08 alleles per ssr and a range from 2 to 3. the lines were located in three groups: group a represented by the tester l20-2#1 together with cml-254, group b represented by cml-144, and a third group that did not group with any of the former two. a correlation analysis was performed between the estimated gd′s and the yield, or the heterosis, and significant correlation was obtained by the latter (r = 0.09 ns vs. r = 0.36 **, respectively). when the distance was correlated between the lines of the opposite group and the tester separately, significant and high values were found only in the comparison cml-144 versus the lines grouped as a with r = 0.55**.