Abstract Selected maize hybrids were analyzed according to the in vivo digestibility of the silage. Eight tested hybrids were grown, harvested, and ensiled under identical conditions. The effect of earliness (early maturity group FAO 230–260 vs moderately early maturity group FAO 290–340) significantly (P < 0.05) affected the chemical composition, fermentation quality, and digestibility of neutral and acid detergent fibre. Type of kernel endosperm (dent vs flint) differed by digestibility of nutrients. Digestibility of dry matter, organic matter, and neutral detergent fibre was the highest for silage of the dent hybrid FAO 250 (73.7, 75.7, and 67.6%, respectively) and these digestibility values were significantly (P < 0.05) lower for silage of the dent hybrid FAO 320 (61.1, 63.4, and 51.4%, respectively). It was concluded that the digestibility differs mainly in dent-type hybrids. All correlation coefficients between the digestibility values were significantly (P < 0.05) high.

Abstract Maize genotype selection represents a practical tool influencing forage yield and quality. The main objective was to investigate the contribution of genotype, site, and year to variability of maize yield and quality in the environment of Central Europe. Totally 63 maize genotypes at 11 sites over a 7-year period were evaluated for dry matter yield (DMY), dry matter content (DM), starch, cob, neutral detergent fibre (NDF), in situ digestibility of stover NDF (NDFD), and organic matter (OMD). The genotype showed the highest variability from all factors where stover NDFD varied from 261 to 529 g kg-1 and stover OMD from 376 to 609 g kg-1. In contrast to the whole-plant, variability of stover traits was more closely related to NDF than the DM content. Under standardized plant DM, all tested factors were significant and allowed interpretation of 70 and 60% of total variation of yield and quality for stover and whole plant, respectively. The average contributions of genotype, site, and year were 30, 7, and 5%, respectively. For variability in plant productivity and nutritive value, the importance of maize genotype selection was more than two times higher than the contribution of environment.

The objective of the experiments was to compare types of maize hybrids harvested at the similar stage of maturity, between one and two thirds of the milk line stage of grain. The study involved 9 hybrids with different parameters that were grown during a period of three subsequent years in two locations with different level of precipitation. Differences in terms of the content of dry matter between the hybrids at different timing of harvests were small (323 ± 22 g/kg), showing no statistical significance (P = 0.34). Comparing the early maturity hybrids with the medium early hybrids (P < 0.05), the former showed a lower content of starch (299 g/kg dry matter (DM)), and the latter showed a slightly higher value (312 g/kg DM) - while the measured proportion of neutral detergent fibre (NDF) among these two hybrids was 453 vs. 428 g/kg DM. Comparing the measured value of the normally ripening hybrids against the stay-green hybrids, the starch was 314 vs. 294 g/kg DM, and NDF was 434 vs. 451 g/kg DM, respectively. As for the comparison between the flint (vitreous) type of grain endosperm vs. dent (floury), measured value of the starch was 298 vs. 323 g/kg DM, and NDF was 451 vs. 427 g/kg DM, respectively.