Soil test based nutrient management for short-duration cassava (Manihot esculenta): Analysis of growth, biomass, yield, quality, nutrient uptake and soil nutrient status

Abstract

Short-duration (6-7 months) cassava ( Manihot esculenta Crantz) enables better utilization of resources and crop diversification than the normal duration crop (9-10 months). Field experiments were conducted for three years (2004-2007) at Thiruvananthapuram, Kerala, in a lowland situation akin to rice fallow to standardise nutrient management practices for short-duration cassava. Five short-duration cassava lines (Vellayani Hraswa, Kalpaka, Sree Jaya, Sree Vijaya and triploid 2-18) were evaluated under 4 levels of fertility (12.5 t FYM (100%)+ NPK, 75% FYM + NPK, 50% FYM + NPK and NPK fertilization based on soil test data) in split plot design with 3 replications. Triploid 2-18 yielded significantly higher fresh tubers (28.45 t/ha) than other four cultivars. The high yielders pro- duced appreciably taller plants and more leaves, higher total and tuber biomass. Nutrient management based on soil test data for organic C, available P and K status along with 12.5 t/FYM, which resulted in the saving of full P, 10% N and 15% K by the third year, promoted plant height, leaf production and nutrient uptake, produced higher tuber yield (24.18 t/ha), tuber and total biomass, dry matter and starch content of tubers besides maintaining or- ganic C, available N, P and K status of the soil, leading to positive nutrient balance.