Effect of integrated nutrient management on growth, yield, quality and soil health of spring planted sugarcane (Saccharum officinarum) in West Bengal

An experiment was carried out during 3 consecutive cropping seasons of 2013–14, 2014–15, and 2015–16 at Bethuadahari, Nadia, West Bengal to evaluate the effect of organic manure and biofertilizers in combination with inorganic fertilizer as the source of nitrogen (N) on growth, yield attributes, cane yield, juice quality, leaf nutrient and chlorophyll content, and soil health after harvesting of sugarcane (Saccharum spp. Hybrid complex) (cv. CoB 94164). The experiment consist of 7 treatments, viz. T₁, control; T₂, 100% recommended dose of N through inorganic; T₃, 75% recommended dose of N through inorganic + 25% recommended dose of N through FYM; T₄, 50% recommended dose of N through inorganic + 50% recommended dose of N through FYM; T₅, T₃ + Azotobacter; T₆, T₃ + Azospirillum; T₇, T₃ + Azotobacter + Azospirillum, respectively in a randomized block design (RBD) with 3 replications. The results revealed that, application of N through organic manure and biofertilizer along with chemical fertilizer increased growth characters, viz. leaf-area index (LAI), total dry matter (TDM), chlorophyll content and N, P, K and S concentration in leaf tissues as compared to inorganic fertilizer alone. The maximum cane yield (86.10 t/ha) and sucrose content (17.52%) were recorded under the treatment T₇ (75% recommended dose of N through inorganic + 25% recommended dose of N through FYM + Azotobacter + Azospirillum). Cane yield exhibited significant positive correlation with different growth and yield attributes as well as with juice quality and vice-versa. The organic carbon, available N, P₂O₅ and K₂O contents of soil increased slightly after harvest of the crop due to the incorporation of organic manures and biofertilizers in soils initially. Thus, 25% of the recommended dose of nitrogen through inorganic sources could be replaced by FYM and biofertilizers for obtaining higher sugarcane yield along with improvement of soil health status.