Grain yield and agronomic traits of maize germplasm from Mexican highlands

The objective of this research was to identify high yielding maize (Zea mays L.) germplasm and to select the best crosses taking as a reference three commercial maize hybrids in the highland central valleys of Mexico. Eighteen crosses among lines and testers and 38 crosses among maize landraces and different testers were included, plus three corn hybrids added as controls. Field experiments were established during the Spring-Summer growing season at Santa Lucia de Prias, Texcoco, Edo. Mexico, in 2002 and 2003. The variables measured were: days to flowering, plant height, cob height, cob length, cob diameter, cob row number, grain yield, grain index and cob sanity. Traits were analyzed under a complete randomized block design with factorial arrangement and three replications. Ten crosses showed outstanding yields in each groups of crosses. In the first group, grain yield varied between 5.0 and 9.3 t ha(-1), while in the second it varied from 5.9 to 9.4 t ha(-1). Among of the outstanding germoplasm some crosses were similar to the control hybrids, in grain yield and other agronomic traits.