Nutrient Efficient Genotypes and Nutrient Management Practices in the Carbon Sequestration Potential of Cassava: A Theoretical Approach

Abstract

Cassava, being considered as one of the food security crops for the present millennium and presumes as tolerant to weather vagaries especially drought, an attempt was initiated to assess the impact of nutrient efficient genotypes and nutrient management practices in the carbon sequestration ability of the crop to delineate it as a benign crop to combat climate change. For this, an experiment was conducted in a triplicated split plot design during 2011 under controlled condition with four genotypes (Ac. No. 766, Ac. No. 788, Ac. No. 130, H 1687) and four nutrient management practices. The nutrient management practices were POP (organic + major nutrients), soil test based fertilizer (STBF) recommendation (organic + major + secondary + micronutrients), POP (organic + major nutrients) + biofertilizers and low input management practice with green manuring in situ with cowpea as organic manure source, STBFR (major + secondary + micronutrients) and nutrient efficient biofertilizers. The parameters calculated theoretically were leaf dry matter production, carbon content in leaf dry matter, atmospheric CO2 absorbed for leaf dry matter production, reduction in atmospheric CO2 and soil organic carbon.The effect of genotypes was significant with Ac. No.130 having the maximum leaf dry matter production, leaf carbon, CO2 absorption and reduction in atmospheric CO2. However, H 1687 recorded the maximum C sequestration which was on par with Ac. No. 130 and Ac. No. 788. Though the nutrient management practices showed significant effect on all parameters, there was no significant effect on carbon sequestered, as the final soil organic carbon was not significantly different. The interaction effect was significantly highest for leaf dry matter production (0.84 t ha-1), leaf carbon content (0.38 t ha-1), CO2 absorption (13.86 ppm) and reduction (371.14 ppm) in the Ac.No.130 under STBF recommendation of organic manure and inorganic fertilizers including secondary and micronutrients.