Interactive Effects of Poultry Manure and Zinc on Growth, Productivity, and Nutrient Uptake of Rice under Indo-Gangetic Plain of West Bengal, India

A field experiment was conducted during the rabi season of 2024 at Ghetugachi, Nadia, West Bengal, to evaluate the combined effects of poultry manure (PM) and zinc (Zn) application methods on rice growth, yield and nutrient uptake. The experiment followed a factorial randomised block design with three replications and 16 treatment combinations comprising four PM rates (0, 150, 250 and 500 g m⁻²) and four Zn treatments (no Zn, basal zinc sulphate, foliar zinc sulphate and seedling root dipping in zinc oxide). Plant growth, yield attributes, grain and straw yields, and nutrient uptake were evaluated. Relationships among measured traits were examined using correlation analysis and principal component analysis (PCA). Poultry manure combined with Zn generally improved crop performance relative to the control. The highest grain yield (6.59 t ha⁻¹) occurred with 500 g m⁻² PM and basal Zn application, representing an increase of 70.28% over the control. The same PM rate combined with foliar Zn produced the highest straw yield (6.18 t ha⁻¹; 59.68% increase) and Zn uptake (294.62 g ha⁻¹; 261.44% increase). Nitrogen, phosphorus and potassium uptake also improved under combinations involving higher PM rates and basal or foliar Zn application. The first two principal components explained 86.38% of the observed variation, with nutrient uptake and grain yield contributing strongly to the first component. These findings indicate that integrating PM with basal or foliar Zn application may improve rice productivity and nutrient uptake under the conditions evaluated.