Nutrient Uptake by Taniers as Related to Stage of Growth and Effect of Age on Yields of the Morada Variety

Abstract

Nutrient uptake by well fertilized taniers of the Morada variety was maximum near harvest time, averaging 125, 15, 156, 48 and 25 kg/ha for N, P, K, Mg and Ca, respectively. Uptake of N and K increased rapidly, but that of P slowly, from planting to harvest. Uptake of Mg and Ca increased steadily up to 5-6 months, after which it fluctuated considerably. Leaf weight increased rapidly during the first 6 months, then decreased and then remained fairly constant until harvest. Leaf lamina of well fertilized taniers contained about 3.2% N, 0.25% P₂O₅, 2.3% K and 1.3% Ca. In two other experiments yields increased from an average of 11,450 kg of tubers/ha 12 months after planting, when taniers are usually harvested, to 28,235 kg/ha 12 months later. Yield of corms, which can be used as pig feed, increased from 9,660 to 45,000 kg/ha over the same period.