Abstract

Field experiments were conducted during rabi 1995-96 and 1996-97 to study the effect of organic and inorganic nitrogen with zinc on growth and yield of rice. The study revealed that application of either green manure (Sesbania aculeata at 6.25 t ha-1 or FYM 12.5 t ha-1 combined with Azospirillum (2 kg ha-1) significantly increased the growth attributes than the combined application of Azolla (I t ha-1). Among the levels of N (112.5, 150 and 187.5 kg ha) with or without 25 kg ZnSO4 ha, combined application of 187.5 kg N ha-1+ 25 kg ZnSO4 ha though recorded significantly the higher growth attributes it was comparable with 150 kg N ha-1+25 kg ZnSO, ha-1. Application of GM with Azospirillum recorded significantly shorter period for 50 per cent flowering, highest number of productive tillers m², filled grains per panicle, panicle length and grain yield (5282 and 5218 kg ha-1) in both the years. Eventhough the highest level of N (187.5 kg har-1) along with Zn application recorded significantly higher yield attributes and yield (5516 and 5376 kg ha-1) it was comparable with 150 kg N ha-1 with Zn.

Keywords: Rice, Organic manures. Biofertiliser, Nitrogen, Zinc, Yield