Effect of zinc and nitrogen fertilization on yield and nutrient uptake of summer rice (Oryza sativa)

A field experiment was conducted during summer 1991 and 1992 with 2 sources of zinc (ZnSO4 and Zn-EDTA), 2 methods of application (soil and foliar) and 4 levels of nitrogen (0, 30, 60, 90 kg/ha) along with 4 levels of sole nitrogen in shallow lowlands with suboptimal (0.84 ppm) zinc level at Bhubaneshwar. Rice (Oryza sativa L.) variety 'Sarathi' (120 days) was used in the experiment. Combined application of zinc and nitrogen recorded grain anti straw yields of 40.1 and 51.5 q/ha respectively compared with 37.4 and 45.6 q/ha obtained from nitrogen alone, giving an additional income of Rs 619/ha. The uptake of nitrogen and zinc increased progressively with increased levels of nitrogen. Among the methods of application, soil application of zinc was superior to foliar spray.