Early selection for oil quality components in olive breeding progenies

Abstract

Olive oil is highly valued for its nutritional quality mainly determined by its fatty acid composition together with the presence of several biologically active minor components. In olive breeding programs, these oil quality components are normally evaluated in the later stages of selection because oil extraction is not suitable for being performed in large seedling progenies with initial low yield. In the present work, we evaluate the ability of open pollinated progenies of 17 olive cultivars located in a large germplasm bank as a means of generate genetic variability for oil quality components directly measured in fruit. High degree of variability was found for most of the oil quality components analyzed, including some cases of transgressive segregation. Narrow‐sense heritability greatly varies among traits, being particularly high for sterol content. Lack of correlation among fruit traits previously reported and oil quality traits suggest the possibility of simultaneous breeding for most of them. In summary, open pollination of cultivars from a germplasm bank together with early evaluation directly in fruit seems to be a convenient strategy for breeding for oil quality traits on olive.Practical application: The evaluation of oil quality parameters directly on fruits here presented could be a convenient strategy to speed up olive breeding programs aimed at obtaining new olive varieties with olive oil of enhanced quality.Box and whisker plots for oil quality components evaluated in progenies from open pollination. Female genitors’ names are abbreviated: “Arbequina” (Arb), “Blanqueta” (Bla), “Canetera” (Can), “Changlot Real” (ChR), “Chorrúo Castro del Río” (CCR), “Empeltre” (Emp), “Hojiblanca” (Hoj), “Lechín de Granada” (LGr), “Lechín de Sevilla” (LSe), “Manzanilla del Piquito” (MPi), “Manzanilla de Sevilla” (MSe), “Morona” (Mor), “Ocal” (Oca), “Picudo” (Pdo), “Picual” (Pic), and two previous selection of our breeding program (Sel1 and Sel2). Progenies are shown in ascending order regarding the values of the Spanish cultivars used as parents (represented by stars).