Barley–field bean intercropping improves grain quality with reduced nitrogen inputs

The practice of growing two or more crops on the same land at the same time is called intercropping, a diversification strategy that enhances the sustainability of cropping systems. Its alignment with high‐input, mechanized feed production has not been thoroughly evaluated, and its impact on grain quality attributes beyond protein remains inadequately addressed. On a loam Xerofluvent soil in Italy, this 2‐year field study compared barley ( Hordeum vulgare L.) and field bean ( Vicia faba L. var. minor ) sole crops and their intercropping under five nitrogen (N) rates (0–200 kg N ha − 1 ) to assess grain quality and nutrient yield. Intercropped barley exhibited higher crude protein concentrations than sole‐cropped across N rates, whereas sole‐cropped barley required high nitrogen inputs to achieve similar protein content. Intercropping increased ether extract and fiber fractions but reduced nonfibrous carbohydrates and total digestible nutrients in barley grain. In field bean, intercropping increased fat and cellulose but reduced protein and digestible nutrient yields. The grain of barley–field bean intercropping resulted in higher protein and fiber concentration, but lower starch and digestibility compared with sole crops. Notably, increasing N fertilization had limited effects on grain quality and nutrient yield in intercropping, suggesting that farmers could use less nitrogen inputs while maintaining grain quality. These findings demonstrate that barley–field bean intercropping can improve grain nutritional balance for animal feeding while reducing dependence on N fertilizers, thereby supporting intercropping as a viable diversification strategy for improving nitrogen‐use efficiency in mechanized feed production systems that use mixed grains.