Reproductive compatibility studies between wild and cultivated strawberries ( Fragaria  ×  ananassa ) to obtain “bridge species” for breeding programmes

LUQUE, ANA CATALINA; DEBES, MARIO ALBERTO; PERERA, MARÍA FRANCISCA; CASTAGNARO, ATILIO PEDRO; ARIAS, MARTA EUGENIA

PLANT BREEDING

WILEY-BLACKWELL PUBLISHING, INC

Año: 2019 p. 1 - 10

0179-9541

The Fragaria genus has become relevant due to worldwide economic importance ofthe octoploid hybrid F. × ananassa. Interspecific hybridizations are widely employedin breeding programmes to introduce useful characteristics from wild species to cultivatedvarieties, although many reproductive barriers prevent gene flow betweenspecies. Hybrid genotypes that can act as a bridge between related wild species andcultivated strawberry could be useful to overcome those barriers. The aim of thiswork was to obtain interspecific hybrids of Fragaria and to analyse possible reproductivebarriers. In the Banco de Germoplasma de Frutilla‐UNT, crossings were carriedout among wild species of Fragaria with different ploidy levels and cultivatedstrawberry. To confirm hybrid condition of genotypes obtained, histological techniquesand microsatellite markers were used. When wild species were crossed withcultivated strawberry in both directions, there was low production of achenes, whilein crosses between wild species of Fragaria genus, achene production was very high.The percentage of germination of achenes was high when crossed species had thesame ploidy level, and very low or null when they presented different ploidy levels.Although pre‐zygotic incompatibility associated to the degree of domestication andpostzygotic barriers related to different ploidy levels of the progenitors weredetected, new hybrid genotypes of Fragaria were obtained. These new hybrids couldbe used as ?bridge species? in breeding programmes, since preliminary resultsshowed no incompatibility barriers when they were crossed with Duchesnea indica.