Intercropping dedicated grass and legume crops for advanced biofuel production

Intercropping dedicated annual summer grass and legume crops could provide local lignocellulosic biomass feedstocks, increase the land resources use efficiency, crop diversification, tolerance and resilience to biotic and abiotic stresses, and the overall sustainability of the system over time. This study aims at evaluating: i) the residual effects of precedent crop (legume or cereal) on the performance of a subsequent biomass sorghum-sunn hemp (Bs x Sh) and pearl millet-sunn hemp (Pm x Sh) intercropping system with and without the application of N-fertilizer; ii) the feasibility and the biomass yield for biofuel conversion of the mentioned intercropping systems, in comparison to the sole crops. The N fertilization had a negligible effect on yields when compared to the effect of the precedent legume (Sh). A similar amount of dry biomass yield (DBY) was observed both in cereal monocropping and intercropping ranging from 19 to 24 Mg ha^-1, whereas the sole sunn hemp reached 14 Mg ha^-1. Pm x Sh outperformed Bs x Sh in terms of evenness with 0.9 and 0.6, respectively, albeit their overall LER is similar and slightly higher than 1. In summary, all cropping systems yielded acceptable amounts of biomass. Among these, the Pm x Sh intercropping system seems more feasible for sustainable lignocellulosic feedstock production.