Effect of different variety and cutting time on yield and quality of forage oat in central and southern Heilongjiang Province

To explore the suitable forage oat varieties and optimal harvest period in Harbin, the capital of Heilongjiang, China, we have comprehensively evaluated the anti-lodging ability, yield, and nutritional indices of 4 oat varieties (i.e., ‘Souris’ ‘Haymaker’ ‘Meida’ ‘Qinghai444’) at different growth stages using principal component analysis. The yield and nutritional qualities were significantly affected by the variety, harvest period, and their interaction (P < 0.05). The results showed that the lodging rates of ‘Souris’ ‘Haymaker’ ‘Meida’ ‘Qinghai444’ were 31.25%, 6.25%, 81.25%, and 87.50% at milking stage, respectively. The fresh matter yield of each variety first increased and then decreased with the delay in harvesting time. The fresh matter yield of ‘Souris’ (crop yield 50.56 t·ha⁻¹), ‘Haymaker’ (crop yield 50.33 t·ha⁻¹), and ‘Meida’ (crop yield 49.33 t·ha⁻¹) were the highest when they were mowed at the filling stage; with no significant differences were noted amongst the yields of these crops. The fresh matter yield of ‘Qinghai444’ (crop yield 36.58 t·ha⁻¹) was the highest when mowed at the milking stage. The dry matter yield of ‘Qinghai444’ gradually increased with the delay in harvesting period, reaching the maximum at the milking stage, when the yield was 11.19 t·ha⁻¹. With the delay in harvesting, the content of water soluble carbohydrate (WSC) also gradually increased. Compared with the jointing stage, the WSC content at the filling stage increased by 38.18%. In summary, ‘Souris’ and ‘Haymaker’ were found suitable for spring sowing in the study area, and could be harvested at the filling stage when both yield and quality were balanced. This would ensure quality and quantity, as well as provide scope for two-season cultivation annually.