Sweet Potato Response to Boron Application on an Alfisols in the Subhumid Tropical Climate of India
ABSTRACT Splitting of sweet potato tubers because of boron (B) deficiency is a major cause of reduction in marketable tuber yield in India. Soil and plant tests are employed in this study to determine the fertilizer B requirement (FBR). Fertilizer B requirement of sweet potatos grown on an Alfisols under rainfed conditions was evaluated by two simple methods. In the first method, the relationship between B uptake and sweet potato tuber yield was utilized to find the B uptake at a given sweet potato tuber yield. This relationship was then used to find the amount of B applied for that particular uptake to set the targeted yield. In the second method, FBR was determined using the equation: FBR=(UB−U0)/BRF, where UB is B uptake at a given yield, U0 is B uptake from unfertilized soil, and BRF is the recovery of applied B. All of these parameters were determined in a field experiment with sweet potatos grown on Alfisols under rainfed conditions. The results of the study indicated a very good relation between observed value of FBR and predicted values determined by both the methodologies. Results of the study suggest that the simple models developed based on B uptake can be utilized for determining the B requirements of sweet potato.