Wadl P.A.,University of Tennessee at Knoxville |
Saxton A.M.,University of Tennessee at Knoxville |
Wang X.,Texas AgriLife Research Center |
Pantalone V.R.,University of Tennessee at Knoxville |
And 2 more authors.
Molecular Breeding | Year: 2011
The objective of our investigation was to acquire information on the association between molecular markers and foliage color in flowering dogwood in order to improve our understanding of the inheritance of this trait and to make possible early selection of red foliage genotypes in breeding programs. A segregating pseudo-F2 population of 94 individuals of flowering dogwood (Cornus florida L.), together with 255 simple sequence repeat markers, was used to identify putative quantitative trait loci (QTL) for foliage color. Foliage color segregated into green- and red-leaved phenotypes and was visually rated for color on five spring dates over 3 years (2007-2009). Repeated measures single-marker categorical analysis of variance (ANOVA) identified four putative QTL (CF309C, CF792A, CF367B, and CF367C) on three linkage groups. Single-marker categorical ANOVA was then used to determine stability of QTL across dates. We identified different QTL, found a low percentage of phenotypic variance explained by the QTL, and detected QTL instability over time, providing evidence of the complex genetics for red pigment expression in flowering dogwood. © 2011 Springer Science+Business Media B.V.(outside the USA).
Sampson B.J.,Thad Cochran Southern Horticultural Laboratory |
Marshall D.A.,Thad Cochran Southern Horticultural Laboratory |
Stringer S.J.,Thad Cochran Southern Horticultural Laboratory |
Sakhanokho H.F.,Thad Cochran Southern Horticultural Laboratory |
Werle C.T.,Thad Cochran Southern Horticultural Laboratory
Scientia Horticulturae | Year: 2014
Some rabbiteye blueberry cultivars (Vaccinium virgatum Aiton syn. ashei) lose ≤67% of their berries to a floral polymorphism (z1-5) that reduces male and female function by deforming corollas, stamens, and pistils. These deformities give flowers an asymmetric shape, and if severe enough, could cause sterility. Overcoming sterility and associated yield loss in 'Premier' flowers was possible with two applications of an exogenous plant growth regulator (PGR), 250ppm gibberellin-A3 (GA). Interestingly, the dual emulsifier and surfactant chosen for our GA dips, 0.5% coconut oil soap, behaved like a PGR by inducing adventitious embyony, possibly apomixis. Resulting berries were 20-25% heavier and matured 7-14 days earlier. Fruit sets as high as 80-90% stemmed from the emulsion's GA ingredient. Yet, the heaviest seed-rich berries either resulted from cross-pollinated flowers or from unpollinated ones treated with GA/coconut oil soap emulsion (hereafter known as the emulsion). A second greenhouse experiment incorporated chemical dips containing four concentrations of coconut oil soap, five component fatty acids with medium length to long-chain aliphatic tails (C10-C18), and three new cultivars. Again, these replicated trials achieved similar results. GA stimulated high fruit set, while coconut oil soap plus its component long-chained fatty acids produced heavier faster growing berries for unpollinated blooms of 'Austin', and 'Prince'. 'Tifblue' flowers however yielded seedless fruit, indicating genotypic sensitivities to exogenous GA. © 2014.