Evaluation of the nitrogen uptake efficacy of daikon radish under greenhouse conditions on sandy soils

Cover crops can be a great addition to agricultural systems to improve soil health and nutrient cycling. One of the many qualities that cover crops possess is recovering residual nutrients. This study was established to estimate daikon radish (Raphanus sativus var. Longipinnatus) nitrogen (N) uptake, partitioning, and accumulation in a short time in Florida conditions. In greenhouse conditions, two Florida sandy soils were planted with daikon radish with three N rates (0, 50, and 101 kg N ha⁻¹ as urea) following a randomized complete block with four replications. The treatments were organized in a two-by-three full factorial arrangement with the three N fertilizer rates. Biomass accumulation, N uptake, and partitioning into shoots and roots were estimated, and residual soil N was calculated. Increasing the amount of N applied to daikon radish plants did not increase biomass production or N accumulation in the shoots and roots of the plants. Daikon radish plants grown without N fertilization were able to produce a similar amount of biomass as those with N applications in their early growth stage. This suggests that daikon radish has the potential to adapt to the sandy soils of Florida and could efficiently utilize the residual soil N. This study shows the potential use of daikon radish as a cover crop in the row middles of citrus groves. The findings suggest that daikon radish plants could thrive in these unfertilized areas and offer promising benefits to the citrus orchards in terms of providing ground cover and additional advantages.