Liming and phosphorus fertilization increase cassava root yield without affecting its cooking time

Abstract

Acidity and low P availability in tropical soils constrain cassava (Manihot esculenta Crantz) yield. Liming increases soil Ca and P availability, but Ca can increase the storage root cooking time, and its effects vary with soil P availability. The effects of liming and P fertilization on cassava yield and their relationship with storage root cooking need to be better understood. A 2-yr field experiment was conducted to evaluate the effect of liming at 0, 1.5, 3.1, and 4.8 Mg ha−1 with 0 or 70 kg P ha−1 on plant nutritional status and growth, yield, and cooking of fresh storage roots of the cassava cultivar IAC 576-70. Foliar concentrations were increased for N, P, and Mg and reduced for Mn and Zn with lime application. Maximum cassava fresh storage root yield (26.4 Mg ha−1) was obtained with an optimal lime rate of 3.0 Mg ha−1 and a base saturation of 50%. Liming promoted a 6.5% increase (1.7 min) in the cooking time of storage roots. Application of P fertilizer increased shoot biomass in acidic soil and the diameter and mean weight of the storage roots in the amended soil. Phosphorus fertilization increased the yield (22% or 4.7 Mg ha−1) and P concentration of the storage roots without changing their P/Ca ratio or cooking time. Liming and P fertilization can be managed to improve cassava storage root yield without affecting storage root cooking.