Abstract

Little work has been done to evaluate the progress made in potato improvement in Ethiopia during the past three decades and information about traits most contributing to progress in yield is scarce. Hence, this experiment was conducted to estimate rate of genetic improvement made over time in yield and to determine traits most contributing to progress in tuber yield. Twenty varieties of potato released in Ethiopia between 1987 and 2013 and one farmers` cultivar were evaluated at Holetta and Adaberga, central highlands of Ethiopia in 2017 main cropping season. The experiment was arranged in a randomized complete block design with three replications. Analysis of variance for tuber yield and tuber related traits showed the existence of highly significant (P < 0.01) differences between varieties for all traits. There was a total tuber yield increment of 137.39 and 0.851% over farmers` cultivar and the oldest variety, respectively. The relative rate of gain was 1.15 and 1.42% year-1 for total tuber yield and marketable tuber yield, respectively. The annual rate of genetic progress was found to be 0.3177 and 0.3401 ton year-1 for total tuber yield and marketable tuber yield, respectively.

Key words: Genetic progress, tuber yield, yields related traits, Solanum tuberosum L., regression.