ChileanJAR

Yield and nutritional characteristics of a total of 16 maize hybrids, one maize cultivar and 3 sorghum per sudan grass hybrids were evaluated at the Exp. Sta. La Platina, during three seasons. A randomized complete blocks design with 4 replicates was used, and the results were analysed through analysis of variance, and by hierarchical clustering, including: (a) dry matter (D.M.) yield/ha and ear percentage; (b) total fibre components; and (c) yield of digestible organic matter (O.M.) and of crude protein (C.P.)/ha. The maize hybrids resulted in markedly higher D.M. productivities, qualitative characteristics, and nutrient yields/ha, than those of the sorghum per sudan grass hybrids. Sudan Cross 3 was of better quality within the sorghums. The maize variety Eureka and the hybid for silage LH Rinconada produced less nutrients/ha in relation to the hybrids commonly used for grain and forage. In general, the yield of digestible O.M. was associated directly with yield of C.P. in the three seasons. With the genotypes evaluated consecutively during the first two seasons, the higher yields of energy and protein were obtained with the maize hybrids G 4507, P 3183, and INIA 150, and these had also the greatest D.M. productivities and ear percentages, and a low fibre contento The comparison among the genotypes evaluated consecutively during the three seasons, clustered the hybrids G 4507, P 3183, and INIA 150 with the highest yields of nutrients/ha, and showed lower values for P 3147, PX 788 and, in the last place, Prays 620; the latter three had in common high fibre contents. The genetical stability in time was high for the three best hybrids indicated above, and conversely, P 3186 and INIA 160 showed variability between years. The hybrids commercially recommended for grain production were superior as silage crops than those promoted for silage or grain and silage.