Three S,-recurrent se ection programs (designated HG, HP, and HGP) for increasing protein yie d of oat (Avena sativa L .) were conducted for five cyc es of se ection . The se ection criteria in each program ( ine of descent) emphasized different components of protein yie d ; high grain yie d in HG, both high protein concentration of the groats (caryopsis) and high grain yie d in HP, and high protein yie d per se in HGP Heading date and height were restricted to no net change . The objectives of this study were to eva uate the agronomic performance of these three ines of descent and the corre ated responses in agronomic traits due to se ection . Thirty to sixty random S oderived ines from each cyc e and ten check ines were grown in hi -p ot experiments at two ocations in 1989 . Grain yie d increased in a three ines of descent ; HG showed the greatest rate of gain fo owed by HGP and then HP (0 .20, 0 .10, and 0 .07 Mg ha' per cyc e, respective y) . Test weight decreased in HGP by 2.6 kg m3 per cyc e and in HP by 4.0 kg m3 per cyc e, but remained constant in HG . Cyc e 5 (C5) means for straw yie d, height, and seed weight were not significant y different from the C o means for any ine of descent . Groat percent remained unchanged in HGP, increased from 70 .1 to 71 .7% in HG, and decreased from 69.9 to 67 .6% in HP. Heading date decreased by 3 d in HG and HGP, but remained unchanged in HP HG compares most favorab y with commercia cu tivars because of its high yie d and acceptab e agronomic traits, whi e HP tends to be ow in test weight, seed weight, and groat percent .