Red clover for silage: management impacts on chemical composition in the season after sowing

摘要

Management impacts on the chemical composition of red clover (Trifolium pratense L.) crops for silage were examined in Ireland. The crops were two diploid cultivars of red clover (Merviot and Ruttinova), each as monocultures or with perennial ryegrass(Lolium perenne L. cv. Greengold). In the first season after sowing, crops received 0 or 50 kg inorganic N fertilizer ha~(-1) in March and the first harvest was on 2 June or 19 June. Subsequent harvests were taken 50, 94 and 191 days after 2 June or 44,86 and 174 days after 19 June. Herbage crude protein (CP) content and preservation indices for ensilage [dry matter (DM) and water-soluble carbohydrate (WSC) contents, buffering capacity (BC)] were measured at each harvest. Red clover mixed with perennial ryegrass resulted in a higher WSC content but a lower BC and CP content than when in monoculture. The early first harvest resulted in a higher WSC content and lower CP, DM and BC for the first-cut herbage compared to the later first harvest. Crops with Merviot tended to have a higher WSC but a lower CP than those with Ruttinova. Spring application of N fertilizer had little impact on herbage chemical composition.