Multiple mowing improves the yield and nutritional quality of Plantago lanceolata on the Loess Plateau

Plantago asiatica has a high feeding quality and can improve the protein utilization rate of ruminants. Therefore, a two-year field experiment was conducted with two utilization modes, multiple mowing (simulated rotational grazing) and once mowing (hay harvesting), to evaluate the dynamics of forage yield and nutrient quality of Plantago lanceolata in typical areas of the Loess Plateau. Compared with once mowing, multiple mowing led to a significant increase in dry matter, crude protein (CP), and ether extract (EE) yields (P < 0.05), and a significant decrease in neutral detergent fiber (NDF) and acid detergent fiber (ADF) content (P < 0.05). The dry matter increased with increasing growth time and accumulated temperature (≥ 0 ℃) by multiple mowing. However, there were significant negative linear relationships between CP, EE content, and growth time, and accumulated temperature (≥ 0 ℃; P < 0.05). Based on the growth time and accumulated temperature ≥ 0 ℃, the predictive models (linear and logistic models) showed that for forage yield and quality, the critical accumulated temperature (≥ 0 ℃) was 2 069～2 984 ℃, and the corresponding growth time in the study area was 102～161 d. This study provides a theoretical basis for the management and utilization of cultivated grasslands on the Loess Plateau.