Effect of fertigation schedule on production potential, quality and nutrient uptake of elephant-foot yam (Amorphophallus paeoniifolius)

The field experiment was conducted to determine the effect of fertigation schedule on productivity and quality of elephant-foot yam (Amorphophallus paeoniifolius Dennst. Nicolson) at Bhubaneswar Regional Centre of CTCRI, Thiauvananthapuram, during 2013 and 2014. The experiment was laid out in split plot design with different fertigation intervals (T₁: 2, T₂: 3 and T₃: 4 days intervals) in the main plots. The recommended dose of fertilizers (soluble fertilizer N, P₂O₅, K₂O @ 120-60-120 kg/ha) were applied in splits (S₁: 30, S₂: 40 and S₃: 50) through drip irrigation in sub-plots. A check [surface irrigation with P₂O₅ 60 kg/ha as basal and N, K₂O @ 120–120 kg/ha during first (40%), second (30%) and third (30%) month after planting (MAP) applied to soil] and the control (surface irrigation without fertilizer) treatments were also included. All the treatments had three replications. The plant height, canopy spread and pseudostem (leaf petiole) girth at third and fifth MAP were maximum in treatments which received maximum nutrients. The treatments T₃S₂ (fertigation in 40 split doses at 4 days interval) and T₂S₃ (fertigation in 50 split doses at 3 days interval) resulted in more corm yield, dry matter and starch content, nutrient (N, P and K) uptake and use efficiency (agronomic efficiency, recovery efficiency and partial factor productivity) but difference between the two treatments were not statistically significant. The control (surface irrigation without fertilizer) resulted in lower calcium oxalate content in corm. Dilution effect of calcium oxalate content was recorded in treatments that resulted in maximum corm yield.