Genetic Gain in Yield and Yield Related Traits of Groundnut [Arachis hypogea (L.)] in Central Rift Valley of Ethiopia

Abstract

The progress made to improve groundnut varieties through breeding in Ethiopia has not been yet assessed. Therefore, in this study genetic gain in grain yield and yield related traits of 14 groundnut varieties developed by the Ethiopian Lowland Oil Crops Research Program (now Ethiopian Lowland Oil Crops Research Project) from 1976 to 2009 was assessed. The varieties were evaluated in RCBD design with three replications in the 2010 main cropping season at Melka Werer Agricultural Research Center and Miesso experimental fields. The analysis of variance indicated significant  differences among the varieties for all traits except days from sowing to emergence. Positive genetic gains were observed for the yield traits (grain yield and yield components), while negative genetic gains were obtained for the phenological traits (50% flowering and pod filling periods). Grain yield was increased from 1.52 to 2.74 tons ha-1 during the last 33 years and the overall increase in seed yield of the latest variety Fetene over the oldest variety Shulamith was estimated to be 1.142 tons ha-1 or 71.4%. Based on the regression analysis, the estimated average annual rate of increase in grain yield potential was 0.03 tons ha-1 year -1 with an annual relative genetic gain of 1.89%. These results demonstrated the efficiency of the adopted breeding strategies in developing varieties with higher grain yields and earlier maturity. This suggests that groundnut breeders can use similar breeding strategies to exploit the genetic potential of the crop for enhanced production.

Keywords: Arachis hypogea; Genetic Gain; Groundnut; Yield Plateau