Combining ability analysis and correlation between breeding values in true potato seed

Abstract

True potato seed (TPS) requires the selection of appropriate parents for developing hybrid offspring. Parents for routine crossing schemes need to be selected according to their combining ability. Hierarchical and factorial mating designs provide a mean values to assess the general combining ability (GCA) of clones included in crossing schemes. Furthermore, specific combining ability (SCA) may be investigated using the factorial mating design. The aim of this research was to determine the combining ability of clones included in early and intermediate TPS breeding populations developed by the Centro Internacional de la Papa (CIP). Likewise, correlations between breeding values (or additive genetic correlation, q A ) were calculated. Two hierarchical mating designs (in both the early and intermediate populations) and one factorial mating design (in the intermediate population) were evaluated in two contrasting Peruvian locations (La Molina -coastal desert, and San Ramon, warm humid tropics). Plant and tuber characteristics were recorded in these experiments. Significant GCA was observed for tuber yield in all experiments. The male's q A between plant vigour after transplanting and tuber yield was significant, thereby suggesting that offspring with early vigorous growth are high yielding. Plant vigour was also correlated with tuber set, but only among the breeding value of female parents, which suggests that high tuber yield could be achieved because offspring with early, vigorous growth have many tubers. High tuber yielding hybrids can be obtained by choosing parents with significant GCA, whose tuber yield can also be further enhanced if the crosses have a significant SCA.

Combining ability of potato parents for tuber appearance and tuber yield component traits

“…The higher GCA values found in this study for yield-related traits agree with reports of some authors (Ortiz andGolmirzaie 2004, Silva et al 2013), but differ from others (Barbosa and Pinto 1998, Gopal 1998, Galarreta et al 2006. The second group reported the predominance of significance of SCA over GCA.…”

Combining ability analysis of yield and late blight [Phytophthora infestans (Mont.) de Bary] resistance of potato germplasm in Rwanda

“…Some authors found both GCA and SCA to be significant for potato yield with GCA being less important in magnitude than SCA (Bradshaw and Mackay, 1994;Gopal et al, 2008;Haydar et al, 2009;Ortiz and Golmirzaie, 2004;Ruiz de Galarreta et al, 2006); whereas other authors (Plaisted et al 1962;Tai, 1976;Killick, 1997;Gopal, 1998) reported GCA to be more important in magnitude than SCA in affecting potato yield. Some other authors reported GCA to be significantly greater than SCA for tuber yields and yield related traits in crosses between non-related parents (Neele et al, 1991;Ortiz and Golmirzaie, 2004). This would be the case found in this study since the clones evaluated were local landraces and CIP derived genetic materials.…”

Combining Ability Analysis for Yield and Its Attributing Traits over Environments in Tomato (Solanum lycopersicum L.)

“…Several studies of combining ability for yield components are available in many species. Some researchers found the predominancy of GCA to be more important than that of SCA reported by Khan et al (1991);Yaqoob et al (1997), while others suggested that SCA was more important reported by Ortiz and Golmirzaie (2004), Biswas et al (2005). The present investigation was carried out to analyze tomato cultivars to ascertain the relative performance regarding combining ability effects for yield and its components.…”