Forty‑five maize populations obtained by crossing between tropical and adapted materials were evaluated in two experiments to find out their suitability as a source to obtain forage maizes.
In experiment one, the chemical composition and the digestibility were studied in thirty‑six populations and com pared with two commercial hybrids. The stover protein content of semiexotic materials was higher than the hybrids' (7.8 % vs 6.8 %), whereas the hybrids exceeded the semiexotics in the cell wall content (73.1 % vs 68.8 %). In spite of this, the dry matter digestibility was 50.1 % and 51.7 % for the semiexotic materials and hybrids, respectively, as the hybrids cell wall digestibility was higher than the semiexotics cell wall digestibility.
In experiment two, another nine semiexotic populations were cultivated in three different places to study the environmental effect on chemical composition and digestibility. All the parameters were affected by the location effect except the cell wall content.