Assessment of Combining Ability Effects for several Yield and Quality Traits in a Complete Diallel Cross of Strawberry (Fragaria × ananassa Duch.)

Abstract

Information on the inheritance of yield and quality traits is important for the selection of parents and breeding approaches to be adopted for the improvement of strawberry. The present study aimed to estimate the combining ability and gene effects for plant yield, fruits number/plant, fruit weight, pulp firmness and sugar content of strawberries in order to identify the best genitors and promising crosses, in 30 hybrids of six parents. The additive and non-additive gene action as well as the maternal effects was involved in the inheritance of the studied traits. For all traits, especially for fruit weight and plant yield, the additive gene action was more important than the non-additive one. The parents ‘A1’ and ‘Alba’ showed a higher concentration of favourable alleles for plant yield and fruits number, and they will allow the increase of plant yield when used as a donor of pollen and the increase of fruit number when used as a recipient of pollen. The variety ‘Marmolada’ was a good general combiner for sugar content, pulp firmness and fruit weight, especially when used as a female genitor. These parents could be used in hybridization in order to accelerate the genetic improvement of some yield and quality traits in strawberries. The cross ‘Mira’ × ‘Onda’ expressed desirable specific combining ability effects for yield traits and can be successfully use in strawberries breeding programs. In the case of ‘Alba’ × ‘Clery’ there is a high probability to select progenies with valuable yield traits associated with sweet fruits.