Comparative Nutritional and Organic Matter of Leaves and Pods from Herbaceous Papilionaceae Ecotype

Crotalaria mucronata and Crotalaria retusa are leguminous plants with potential in their leaves, pods, and seeds. However, this potential remains largely underutilized. This study aimed to assess the nutritional content, organic matter, and antinutritional factors in the leaves and pods (including seeds) of C. mucronata and C. retusa from various ecotypes in Burkina Faso. The organic matter content was determined from the organic carbon content. Na was determined with a flame photometer. N, Cu, P, Mg, Mn, and Zn with the atomic absorption spectrophotometer. Alkaloids were determined by gravimetry. Tannins were determined using the AOAC method. Significant variations in nutrient and element content were observed across ecotypes, especially for nitrogen (for leaves, p = 0.021 and pods, p = 0.0001), phosphorus (for leaves p = 0.0001 and pods p = 0.0001), sodium (for leaves, p = 0.001 and pods, p = 0.002), manganese (for leaves, p = 0.006 and pods, p = 0.001) and magnesium (for leaves, p = 0.049). High organic matter content was found in both leaves (91 ± 1 mg/kg) and pods (96.67 ± 7.05 mg/kg). Nitrogen content was highest in leaves from Gonsé (27 ± 3 g/kg) and pods from Arbollé (29.83 ± 1.00 g/kg). Phosphorus levels ranged from 1.72 to 2.79 g/kg in leaves and 1.82 to 3.34 g/kg in pods. Sodium content was relatively low compared to some other legumes. Magnesium levels were highest in pods (up to 1701 ± 12.6 mg/kg) and lower in leaves. The pods and leaves can be used as organic matter or as potential forage.