COMBINING ABILITY AND MATERNAL EFFECTS IN MEXICAN RACES OF MAIZE THROUGH GRIFFING MODEL I

Abstract

The objective of this research was to determine the genetic components of agronomic traits and yield in diallel crosses between ten races of maize from Mexico, using the Griffing I model. The crosses and races were evaluated in the experimental field of the Instituto Tecnológico Roque in Celaya, Guanajuato, in 2011. The traits evaluated were grain yield, days to tasseling and silking, plant height, leaf number, prolificacy, 1000-grain weight, number of rows per ear, number of grain per row, ear length and diameter. The ANOVA showed significant differences for genotypes and traits evaluated for most variables. The additive genetic effects were more important and contribute more that non-additive effects. Reciprocal effects were observed for all traits except for plant height and prolificacy, which is mainly attributed to maternal effects (general reciprocal effects). The Bolita and Tabloncillo races showed the lowest estimators for flowering, while Tuxpeño and Jala exhibited the highest one. Rergarding yield, the races with the highest estimators were Tuxpeño and Celaya; for ear length Jala had higher values compared with the other races, while the highest estimator of 1000-grain weight corresponded to the Ancho Pozolero. Direct and reciprocal cross of Tabloncillo by Pepitilla showed negative effects for days to silking, while Tabloncillo by Bolita and Tabloncillo by
Dulce showed negative effects to tasseling. Crosses with the highest yield were Tepecintle by Dulce and Celaya by Tuxpeño. For cob length the crosses Dulce by Jala and Jala by Bolita presented the highest values.