Recurrent Selection in Oat: Stability of Yield and Changes in Unselected Traits

Abstract

Recurrent selection, primarily for grain yield in oat (Avena sativa L.), has been practiced at a single location for four cycles. Previous evaluations of this program had indicated that grain yield had been increased and that correlated changes, some undesirable, had also occurred. In some studies in other species, yield increases have come at the expense of stable productivity. The objectives of this study were to evaluate the stability of grain yield and to assess changes in nine unselected traits to determine the potential of lines from this program for cultivar development. Grain yield was measured in 23 trials during a 5‐yr period to evaluate gain from selection and compare the average yield stability of the 12 initial parents with that of the 21 fourth cycle parents (lines selected from the third cycle). Seven agronomic and seed quality traits (days to heading, plant height, resistance to lodging, test weight, groat percentage, percentage groat protein, and percentage groat oil) were evaluated in 12 trials to examine correlated response to yield selection. Barley yellow dwarf (BYD) and loose smut reactions were evaluated in inoculated disease nurseries. Gain from four cycles of yield selection ranged from ✕2.0 to 44.6% in the individual environments, and was usually significantly positive. Also, based on regression stability statistics, selection for grain yield increased the ability of the selected materials to respond to more favorable environments. Finally, there were significant correlated responses for all but two of the unselected traits, groat percent and BYD reaction; however, even though most of the changes were undesirable they were relatively small and should not detract from the potential of the fourth cycle parents in a cultivar development program.