F.S. Okelola, I.T. Lawal, M. A. Adebisi Variability, rice, vigour, seed yield, seed improvement 82-91 6 (3) 2022 July 2022 Twenty-two rice varieties were evaluated in a field trial under rain-fed conditions at the National Agricultural Seeds Council, Sheda, Abuja in 2017 and 2018 cropping years to provide a comparative measure for effects of genotype by year interaction on physiological performance of selected Nigerian rice. The experimental field was laid out using Randomized Complete Block Design in three replicates. Significant variation were detected among varieties during and across the cropping years evaluated for all the eight seed quality attributes. Higher values of rate of germination, seedling vigour, 100 seed weight, seedling shoot length, coleoptile length and number of roots were observed in 2017 cropping season compared to 2018 cropping year with superiority advantage of 18.39, 12.49, 9.37, 20.00, 31.07, 14.09 and 45.71, respectively. FARO 41 had consistent and highest performance for most of seed quality attributes (rate of germination (83.50%) seedling vigour (13.25%), seed germination (89.53%) and number of roots (3.25). Seed germination was strongly related to seedling vigour, seedling root length, 100 seed weight and number of roots (r=0.21-0.86**). The study concluded that FARO 41 as well as FARO 31 with superior performance in seed quality attributes are thus recommended for seed improvement programme.