Significance of Groundnut Inoculation and NP Fertilizer Application on Yield, Nitrogen Uptake, Fixation and Soil N Balance Sheet under Rainfed Conditions

Abstract

A study was carried out at two different locations in northern Punjab-Pakistan to elucidate the effect of inoculum and fertilizer application on growth and nitrogen fixation of two varieties (BARI 2000 & Golden) of groundnut (Arachis hypogea) under rainfed conditions. The treatments comprised of different combinations of two levels of nitrogen (0 and 20 kg ha^-1) and two levels of phosphorus (0 and 80 kg P₂O₅ ha^-1) with and with out inoculation. Application of fertilizer and inoculum resulted in significantly higher dry matter yield as compared to control at both the locations, however effect was not significant on pod yield. The percent nitrogen derived from atmosphere was in range of 32 to 49 and was not significantly affected by either fertilizer or inoculum application. Amount of nitrogen fixed increased by 40% at Chakwal and by 11% at Talagang due to fertilizer combination of 20 kg nitrogen and 80 kg phosphorus ha^-1.

Keywords: Arachis hypogeal, Inoculation, Pod yield, N fixation, N balance