The purpose of this study was to determine in the maize (Zea mays L.) the existence of some combinations with combining ability, higher than the crossing Reid x Lancaster with high feeding value. For this reason a diallel crossing among seven Spanish and two American populations has been analysed, using II and III analyses proposed by GARDNER y EBERHART (1966).
The variaton sources for entries, populations and general combining ability (GCA) were highly significant for grain yield and protein and fiber content. For oil content, significant for entries was observed. The crossing BS‑13 x Lancaster, which represents the Reid x Lancaster heterotic pattern, provides the highest productions. The BS‑13 x Andaluz crossing, whose difference is not significant, follows the previous one. Besides, the BS‑13 x Andaluz crossing provides higher protein content than the established heterotic pattern. The crossing of two Spanish populations (Rastrojo x Blanco), both with good GCA, provided the highest protein production.