|SOORIYAPATHIRANA, SUNETH - University Of Peradeniya|
|MOOKERJEE, SONALI - Michigan State University|
|WEEBADDE, CHOLANI - Michigan State University|
|LUBY, JAMES - University Of Minnesota|
|STEWART, PHILIP - Driscoll'S|
|NEILS, STUART - Michigan State University|
|HANCOCK, JAMES - Michigan State University|
Submitted to: Journal of Berry Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/27/2015
Publication Date: 9/15/2015
Publication URL: http://handle.nal.usda.gov/10113/62432
Citation: Sooriyapathirana, S., Mookerjee, S., Weebadde, C.K., Finn, C.E., Lewers, K.S., Bushakra, J., Luby, J.J., Stewart, P., Neils, S., Hancock, J.F. 2015. Identification of QTL associated with flower and runner production in octoploid strawberry (Fragaria × ananassa). Journal of Berry Research. 5:107-116. doi: 10.3233/JBR-150095.
Interpretive Summary: Breeding of strawberries, a fruit which has many valuable nutritional properties, is slow in part because seedlings derived from breeders’ crosses must be grown to maturity for evaluation of many traits, including whether the plant will produce fruit all spring and summer or just a condensed crop under favorable temperature conditions in the spring. The breeding process would be greatly accelerated, and would be much more efficient, if a breeder could test a small seedling and know with confidence what traits that seedling will have if grown to maturity. A DNA based method, called “marker assisted selection” is available to accomplish this, but requires DNA “markers” that can be used to identify the seedlings the breeder should “select”. This research reports the discovery of markers that can be used to select seedlings that produce strawberry fruit in hot summer temperatures. Strawberry breeders and geneticists worldwide will use these markers to breed improved strawberries.
Technical Abstract: Seasonal flowering of strawberry is described as remontant and non-remontant. The genetic basis of this trait is important for breeding. This study was conducted to validate the existence of a major QTL for remontancy and weeks of flowering in F. × ananassa on LG IV, to determine if the level of floral heat tolerance co-segregates with a QTL determining remontancy and weeks of flowering, and to determine whether the QTL for remontancy also regulates runner production as in other related studies. Previously collected phenotypic data from two remontant ‘Tribute’ × non-remontant ‘Honeoye’ strawberry populations and SSR markers were used to search for QTL associated with repeat flowering, weeks of flowering and runner production, as well as the ability to produce flowers and runners at 17, 20 and 23 ºC. As discovered in other studies, we found a major QTL that regulated remontancy and weeks of flowering on Homeologous Group IV of ‘Tribute’. This QTL also had a negative effect on runner production and a positive influence on flower production under high temperatures. A number of additional QTL were discovered that influenced flower and runner production. In summary, remontancy/non-remontancy is controlled by one genomic region with a major effect and several minor modifying ones.