|Publication Type:||Journal Article|
|Year of Publication:||2012|
|Authors:||LYNCH, JP, O’Kiely, P, Doyle, EM|
|Journal:||Grass and Forage Science|
|Keywords:||cob, harvest date, hybrid, maize, silage, stover|
The objective of the study was to determine the effects of maize hybrid and harvest date on the yield, quality and subsequent conservation characteristics of whole-crop, cob and stover silages. The experiment had a split-plot design, with three main plots (date of harvest) and six subplots (hybrid) in each of three replicate blocks. Four maize hybrids (Tassilo, Beethoven, Andante and Nescio) were conventional hybrids used in commercial livestock production in Ireland, and two were categorized as high-biomass hybrids (Atletico and KXA 7211). The three harvest dates – 16 September, 7 October and 28 October – represented early, normal and late harvests respectively. Averaged across hybrids, harvesting on 16 September reduced the DM yield (P < 0·05) and starch concentration (P < 0·01) of whole-crop and cob, and decreased the neutral detergent fibre (P < 0·05) and acid detergent fibre (P < 0·01) contents of stover. Later harvesting date generally resulted in a more restricted, heterolactic fermentation that was associated with increased dry-matter (DM) content at ensiling. Whole-crop and stover from Atletico and KXA 7211 generally had higher DM yields (P < 0·05) and a more extensive fermentation compared to Tassilo, Andante and Nescio. Despite the high-biomass hybrids having a higher DM yield than conventional hybrids, the high-biomass hybrids had a lower (P < 0·05) content of cob and a corresponding higher (P < 0·05) content of stover. The changes in proportions of cob and stover in whole-crop maize with later harvesting significantly influenced its silage digestibility and conservation characteristics.
|Short Title:||Grass and Forage Science|