Nutrient Dynamics and Partitioning for Sustaining Sugarcane Productivity Through Integrated Use of Biochar, Solid Digestate, Ash with Variable Dose of Fertilizers, Under Trans Indo-Gangetic Plain

A field experiment was conducted to evaluate the effects of integrated use of various organic sources with different doses of synthetic fertilizer on soil nutrient dynamics, nutrient partitioning in sugarcane plants, and its impact on sugarcane productivity. The experiment comprised 16 treatment combinations, replicated thrice in a Randomized Complete Block Design. The results revealed that the significantly higher leaf-stem ratio (0.29), dry matter accumulation (735.8 g/cane at harvest), millable cane (157,900/ha), cane length (240.6 cm), cane girth (7.05 cm), cane weight (1735.5 g), and cane yield (91.2 t/ha) of sugarcane were obtained with the integration of 100% synthetic fertilizers along with 4 t/ha solid digestate (T₄). In contrast, the lowest values for these parameters were observed under 100% N through solid digestate. Soil nutrients dynamics after harvest indicated that available soil N, P, and K were highest under the 100% synthetic fertilizers along with 4 t/ha solid digestate treatment. Further, this treatment observed the highest positive apparent balance of N, P, and K in soil and zinc partitioning. Soil microbial biomass carbon was highest under the 100% N through solid digestate treatment. The integration of synthetic fertilizers with organic sources, particularly solid digestate, resulted in improved nutrient availability and sugarcane productivity, highlighting the effectiveness of nutrient management strategies for maximizing sugarcane yield and sustainability.