Influence of nitrogen and calcium on cooking quality and mineral content of Xanthosoma sagittaefolium

Abstract

Studies were made on the effect of 4 calcium and 4 nitrogen levels on cooking quality and mineral content of Xanthosoma sagittaefolium. Three factors were associated with cooking quality, namely cooking time, toughness and crude fiber content of the leaves. Leaves of plants grown at the 4 calcium and 4 nitrogen levels were tested for 16 minerals. Two separate experiments were conducted in the greenhouse, one for calcium and one for nitrogen. Plants were grown in fine gravel and watered daily with the respective nutrient solutions. The 4 calcium levels were 40, 80, 150 and 250 ppm. Nitrogen was tested at levels of 56, 100, 200 and 300 ppm. Results indicated no effect of either calcium or nitrogen on cooking time. Calcium had a small effect on the toughness of Xanthsoma sagittaefolium leaves. Nitrogen had no measurable effect on toughness of the leaves. Both calcium and nitrogen had a significant effect on crude fiber content. The percentage of crude fiber in the leaves was increased with increasing amounts of calcium and nitrogen in the nutrient solution. No relation could be established between the amount of crude fiber, toughness and cooking time. Calcium levels in the nutrient solution had a significant effect on the amount of nitrogen, potassium, barium, strontium, and manganese in the leaves. Nitrogen levels in the nutrient solution significantly affected the concentration of nitrogen, potassium, magnesium, silicon, iron, strontium, boron and zinc in the leaves.