|CASTRO, PATRICIA - University Of Cordoba|
|HANCOCK, JAMES - Michigan State University|
|WEEBADDE, CHOLANI - Michigan State University|
|DIE, JOSÉ - University Of Cordoba|
Submitted to: BMC Plant Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/23/2019
Publication Date: 9/5/2019
Citation: Lewers, K.S., Castro, P.R., Hancock, J.F., Weebadde, C.K., Die, J.V., Rowland, L.J. 2019. Evidence of epistatic suppression of repeat fruiting in cultivated strawberry. Biomed Central (BMC) Plant Biology. https://doi.org/10.1186/s12870-019-1984-7.
Interpretive Summary: Consumers want strawberries all year long. Strawberry breeders are developing new kinds of repeat-fruiting strawberry plants that will produce fruit from spring through fall. An improved understanding of the inheritance of repeat-fruiting is needed to develop the new strawberries. Strawberry breeding parents and their seedlings were analyzed with DNA technology to see which had a gene for repeat-fruiting. The results showed that inheritance of repeat-fruiting is controlled by more than the one gene already known to strawberry breeders, and that breeding new repeat-fruiting strawberries will be more complicated than previously thought. This insight will be important to strawberry breeders and geneticists world-wide.
Technical Abstract: Consumers want fresh strawberries all year long. Extending the fruiting season for new strawberry cultivars is a common breeding goal. Understanding the inheritance of repeat fruiting is key to improving breeding efficiency. Several independent research groups using multiple genotypes and analytic approaches have all identified a single genomic region in strawberry associated with repeat fruiting. Markers mapped to this region were used to evaluate breeding parents and progeny from the USDA-ARS strawberry breeding program at Beltsville, Maryland. Markers mapped to repeat fruiting identified once-fruiting genotypes but not repeat-fruiting genotypes. Family segregation ratios could not reliably be predicted by the combined use of parental phenotypes and marker profiles. Around half breeding parents with repeat-fruiting marker profiles were once-fruiting, indicating at least one additional locus acting epistatically to suppress repeat fruiting. Expected segregation ratios were calculated for all phenotypic and marker-profile combinations possible from the mapped locus combined with a hypothetical dominant or recessive suppressor locus. Although many of the observed ratios could be explained by one model or the other, many could not, and when multiple families with a parent in common were compared, there was no predicted genotype for the common parent that would lead to all the observed segregation ratios. Therefore, the possibility that multiple suppressor loci, some dominant, some recessive, and perhaps some acting together to control the action of the single mapped locus must be considered.