Corn-Palisadegrass Intercropping Effects on Nitrogen (N) Budget.

Corn-palisadegrass intercropping can present differential nitrogen (N) budget as compared to the same crops when grown in monocultures. Following this rationale, field experiments were conducted over two years to measure fertilizer N requirement and N budget for the corn-palisadegrass intercropping system. Four cropping systems were used: (i) corn monoculture, (ii) palisadegrass monoculture, (iii) corn and palisadegrass intercropping under no-tillage and (iv) crop-livestock integration. At early growth, 150 kg N per hectare were applied to all treatments; while 120 kg N per hectare were added at a later growth stage. After corn harvest (off-season), the palisadegrass monoculture accumulated not only the maximum dry matter, but also superior N derived from fertilizer (NDFF) and total plant N. The corn-palisadegrass intercropping system achieved higher total plant biomass and N relative to the monoculture corn system, but NDFF were similar. The intercropping system did not affect N dynamics in soil, but presented superior plant biomass and N early during the growing season as relative to the other cropping systems evaluated. In overall, N fertilizer use efficiency was not affected in both growing seasons. Concluding, corn-palisadegrass intercropping system is a promising option to produce plant biomass and capture N during the off-season in early growth systems to tropical agriculture.