Combining ability analysis of earliness and yield of potato (Solanum tuberosum L.) genotypes in Uganda

Combining Ability Analysis of Dry Matter Content, Reducing Sugars and Yield of Potato (Solanum tuberosum L.) Genotypes in Uganda

“…Both additive and none additive gene action was involved in the expression of average weight per tuber as both GCA and SCA mean squares were highly significant. These results conform with the study by Galarreta et al, [32], however there other studies that have reported additive gene action to be predominant for average weight per tuber [33,34,35]. Additionally in this study the none-additive gene action was more predominant than the additive gene action because of the high broad sense coefficient of genetic determination of 90.3% and low bakers ratio of 0.17.…”

“…This is in accordance with other studies that reported SCA effects as greater than GCA effects for yield [32,33,36]. However some other authors have observed additive genetic effects being more predominant for total tuber yield [34,35]. None the less there still some authors who have reported both additive and non additive genetic gene action to be important for yield [32,37].…”

“…None significant GCA and SCA mean squares for total tuber yield shows that there was little genetic diversity among the parents as far as total tuber yield was concerned [35]. But with a baker's ratio of 0.44 it was indicative of a predominance of none additive genetic effects controlling total tuber yield.…”

“…These variations in the significance of GCA and SCA effects for traits of this study as compared to other studies could be due to the differences in genetic material used. Additionally the tetrasomic inheritance nature of the potato makes combining ability effects specific to a particular set of genotypes that are used as parent to make a progeny population [20,35,36,38].…”

“…A parent to be qualified as good, in that it can pass on a desirable trait is described as that parent which has significant GCA effects in the desirable direction for that trait of interest [39]. The desirable direction for dry matter content and yield components is positive gene action while reducing sugars is negative gene action [19,35,37,40]. Both desirable and un-desirable GCA effects were passed on to the respective progenies in this study; parents 391046.14 (0.9), NAROPOT 3 (0.5) and 395096.2 (0.4) ( 17 x Rutuku of which both parents had undesirable GCA effects, but it had a significant SCA effect indicating a deviation in performance that was predicted on the basis of GCA of the parents.…”