Exploring the Impact of Organic-inorganic Coupling on Nutrient Use Efficiency and Cane Yield in Calcareous Soils of the Indo-gangetic Plains of India

Improving nutrient use efficiency beyond its typical ceiling of 50% is imperative for enhancing sugarcane production and juice quality, while concurrently reducing reliance on synthetic fertilizers and mitigating environmental impact. To address this challenge, a field experiment was conducted during the year 2021–2022 at the Kalyanpur research farm of Dr. Rajendra Prasad Central Agricultural University, Pusa, Bihar. The study aimed to evaluate the effects of integrated nutrient management on sugarcane yield and nutrient utilization efficiency in spring-planted crops like sugarcane. Employing the randomized block design with three replications, the experiment utilized the sugarcane variety CoP-112. Although various treatments exhibited no significant influence on parameters such as germination percentage, plant height, cane length, diameter and individual cane weight, the combination of the recommended dose of fertilizers (RDF) with vermicompost and biofertilizer (Azotobacter + PSB) at a rate of 4 kg/ha resulted in the highest millable cane (125.4×103/ha) and cane yield (94.0 t/ha). This combination led to an increase of 78% and 24% over the sole prescribed dose of fertilizer and the absolute control, respectively. No substantial differences were observed in juice quality among treatments. The maximum agronomic use efficiency was achieved in plots treated with RDF + vermicompost + Azotobacter + PSB, exhibiting a 75% improvement over plots receiving only the recommended dose of fertilizer. The findings underscore the efficacy of integrated nutrient management as the optimal approach for fostering sustainable sugarcane production.