Augmented Designs for International Yield Trials

Abstract

The international yield trial program at ICARDA involves screening a large number of new varieties at a large number of locations around the world. In the past, these trials consisted of a single rows of the new varieties along with rows of a check, or standard, variety placed systematically throughout the trial. The new varieties were evaluated, subjectively, by comparing their yield to that of a nearby check. Since the new varieties were not replaced no valid means of statistical analysis was available. In an effort to put yield evaluation on a sounder statistical basis the Food Legume Improvement Program and the Cereals Improvement Program have adopted “augmented designs” for some of their yield screening trials. These designs were developed by W.T. Federer (“Augmented designs”., Hawaiian Planters” Record 55, 191-208, 1956) for the purpose of the evaluation, including statistical analysis of a large number of varieties.