DIFFERENTIAL GROWTH, NODULATION AND NITROGEN-FIXATION EFFICIENCY OF GROUNDNUT CULTIVARS INOCULATED WITH DIFFERENT RHIZOBIUM STRAINS

Growth, nodulation and nitrogen (N) fixation efficiency of Banki (Loca l) and ICGS-44 (exotic) varieties of groundnut was significantly (P < 0.05) improved by their inoculation either with NC-92 or Rudy Patric ( R.P.) strains of rhizobium. Nodules did not form without inoculation i n plants growing in sterilized sand. Inoculation with R.P. strain of r hizobium resulted in greater shoot growth, N content in shoot and numb er and weight of nodules in groundnut varieties. The R.P. inoculant in creased agronomic efficiency by 112.5% in Banki and 100% in ICGS-44 va riety of groundnut. Improvement in N fixation efficiency by inoculatio n with R.P. inoculant was 334 and 286% in Banki and ICGS-44 variety, r espectively. However, Physiological efficiency was maximum in Banki va riety when inoculated with NC-92 strain of rhizobium.