Effect of Zn fertilizers and Zn solubilizing bacteria on yield, nutrient uptake and economics of rice (Oryza sativa L.)

A field experiment was performed to study the effect of Zn sources combined with Zn solubilising microorganisms-ZSM (Acinetobacter calcoaceticus + Pantoea agglomerans) on yield, nutrient uptake, phytic acid and economics of rice (Oryza sativa L.). The experiment was conducted for two consecutive years (2018 and 2019) at Banaras Hindu University, Varanasi. The experiment was designed in randomized block design with twelve treatments replicated thrice. The data indicated that 25 kg ZnSO4.7H2O ha-1 + ZSM significantly increased tillers over other treatments, but 9.8 kg ZnO ha-1 + ZSM improved panicle length, filled spikelet panicle 1 and test weight. The phytic acid content in rice was found superior in control treatment (6.5 g kg-1), whereas significantly reduced in 25 kg ZnSO4.7H2O ha-1+ ZSM treatment. Moreover, the maximum grain yield (5.01 t ha-1), straw yield (7.85 t ha-1), net return (Rs 58.94 ×103 ha-1) and benefit: cost ratio (1.88) was recorded with 9.8 kg ZnO ha-1 + ZSM. The higher uptake of nitrogen and potassium was recorded in 25 kg ZnSO4.7H2O ha-1+ ZSM treated plot. However, phosphorous uptake was maximum in control. The maximum total Zn uptake (1364.8 g ha-1) was documented with 9.8 kg ZnO ha-1 + ZSM + cow dung.