Comportamiento de compuestos F7 de maiz con relacion al rendimiento y otros caracteres de sus variedades componentes.

Español; castellano. Se evaluaron 24 variedades de maiz de la raza Chalqueno y nueve compuestos formados con ellas. Las 24 variedades se aleatorizaron para formar tres compuestos de cuatro, tres de seis y tres de ocho variedades, los cuales se recombinaron siete ciclos. El estudio se realizo en cinco ambientes usando un diseno experimental de bloques completos al azar con cinco repeticiones. Los resultados indicaron que: 1.-El comportamiento de un compuesto depende de las caracteristicas de sus variedades componentes, 2.-los compuestos superaron en rendimiento y en la mayoria de los caracteres estudiados al promedio de sus variedades componentes, 3.-los compuestos, respecto a su mejor variedad componente, resultaron de igual rendimiento; mayor precocidad, longitud de mazorca y numero de granos por hilera; pero, de menor diametro de mazorca, numero de hileras por mazorca, altura de planta y altura de planta y mazorca, 4.-la varianza fenotipica de los compuestos fue igual al promedio de las varianzas de sus variedades componentes y a la de su mejor variedad componente, y 5.-el mejoramiento genetico debiera basarse en compuesto en generaciones avanzadas, integrados con variedades sobresalientes.

Inglés. The goals of this research were to study the performance of composites with respect to their component varieties and determine if a composite or its best component variety is a better choice to develop a breeding program through selection. Twenty four open-pollinated varieties of maize from the Chalqueno race and nine composites made with them were evaluated. The twenty four varieties were randomized to construct three composites of four, three composites of six, and three composites of eight varieties, which were recombined through seven cycles. The varieties and the composites were planted for agronomic evaluation in a randomized complete blocks design with five replicates, in five environments. Results indicate that: 1.-The performance of a composite depends upon its component varieties; 2.-the composites were better than the average of their component varieties for grain yield and most of the traits, studied; 3.-each composite, as compared to its best component variety, resulted with equal yield; earlyness, ear lenght and row kernel number, were higher; ear diameter, rows per ear, plant and ear height were lower; 4.-the phenotypic variance of a composite was equal to the average phenotypic variance of its respective component varieties and equal also to that one of its best component variety; and 5.-a breeding program should be based upon composites in advanced generations, integrated with standing varieties.