Balancing grain and forage production in dual-purpose cereals: physiological basis, yield variation, and economic evaluation

Dual-purpose crops have become an indispensable part of crop-livestock systems. However, selecting suitable crops and implementing dual-purpose management pose unpredictable challenges to achieving suitable yields and economic returns. This study analyzed the effects of two treatments (grain and grain + forage) on the yield and photosynthetic and antioxidant properties of four crops (barley, triticale, oat, and wheat) over three growing seasons (2021–2022, season 1; 2022–2023, season 2; and 2023–2024, season 3) and assessed the yield and economic benefits. Compared to oat, barley, and triticale, grain + forage reduced (P < 0.05) the fresh matter and dry matter yields of wheat in the post-cutting growth period and grain yield at harvest. The fresh matter and dry matter yields at harvest of grain + forage were reduced (P < 0.05) by 31.7% and 21.5% compared with those of grain only, respectively. The factor analysis model constructed based on photosynthetic and antioxidant indicators (13 indicators) was ordered season 1 > season 2 > season 3 based on season, oat > wheat > triticale > barley based on crop, and grain only > grain + forage based on cropping system. Dual-purpose cropping demonstrated economic viability and sustainability by improving the harvest index despite reduced grain yield. However, the instability of rainfall has become the most critical natural factor limiting the promotion of dual-purpose crop management. When considering dual-purpose or grain-only cropping systems, oat emerged as the optimal choice, whereas for forage production, barley was the ideal singular crop.