Genetic variability, treatability in the broad-sense and expected genetic advance under selection for nine physiological traits were studied in 22 rainfed upland rice genotypes during wet seasons of 1988 and 1989. The maximum genetic variability was observed for RGR in 1988 and CGR in 1989. The CGR, RGR, NAR, and SLW had consistently high (>75%) heritability values associated with high genetic advance indicating the predominance of additive gene effects in the inheritance of these traits. Thus effectiveness of the selection for improving these characters has been emphasised.
