The USDA blueberry breeding program was initiated in 1910 by Dr. F.V. Coville and has been continuous since that time. Plant breeders Drs. G.M. Darrow, D.H. Scott, J.N. Moore, and A.D. Draper have worked with SAES and private growers to develop the majority of cultivars presently grown for commercial production. In the South, major cooperators with the USDA include SAES in Arkansas, North Carolina, Georgia, and Texas. Recently the USDA Station at Poplarville MS, has been instrumental in blueberry cultivar development for the South. Rabbiteye blueberry cultivars make up the majority of blueberry acreage grown in the region. A new type of blueberry, the southern highbush (SHB), has been developed by interspecific hybridization with various Vaccinium species. Late-blooming SHB cultivars have been developed that offer better protection from spring frosts and ripen earlier than the earliest rabbiteye blueberry. Genes required to meet future needs reside within native Vaccinium species. Progress has been made in plant adaptation, disease resistance, fruit quality, and season of ripening. There remains a need for greater plant vigor, insect resistance, and consistent production.
Arlen D. Draper
Patricio A. Brevis, Nahla V. Bassil, James R. Ballington, and James F. Hancock
also improved fruit quality traits such as picking scar, firmness, color, and flavor ( Draper, 1997 ). Although highbush blueberry breeding has been reviewed multiple times, it has been difficult to assess the genetic contributions of wild germplasm to
James W. Olmstead and Chad E. Finn
blueberry breeding program might take to enable selection for MFF. Short-term strategy Because the development timeline for highbush blueberry cultivars can take 10–15 years, adoption of MFF in the near future will require the use of existing cultivars
Timothy F. Wenslaff and Paul M. Lyrene
Two clones of anthocyanin-deficient (AD) Vaccinium elliottii (2×, homozygous recessive, yy) were used as seed parents in experiments combining normal and AD pollen. AD gives a seedling marker to distinguish the pollen parent. In the first experiment, flowers were pollinated daily for one, two, three or four days. AD and normal V. elliottii pollen were applied on separate days. The last day of each treatment received the opposite genotype from the previous day(s). The first pollination gave as many, or more, seedlings as later applications but the number of seeds per fruit was higher with multiple pollen applications. The second experiment used pollen from normal V. corymbosum (4×) alone or mixed with AD pollen from the 2× clones. Results depended on the seed-parent genotype. There was no difference between treatments in the number of hybrids produced by W81-1, which tends to set fruit even with only one seed per berry. Only mixed pollen yielded hybrids from clone FL83-139, which was never observed to produce berries with only one seed; apparently the mentor AD pollen helps to set the fruit, thereby allowing the rare hybrid seeds to develop.
Elliot H. Norden, Paul M. Lyrene, and Jose X. Chaparro
. elliottii has been used to a limited extent in blueberry breeding programs in North Carolina and Florida. The intent has been to obtain cultivars that incorporate the ability of V. elliottii to grow on drought-prone upland soils that have low organic
Jessica L. Gilbert, James W. Olmstead, Thomas A. Colquhoun, Laura A. Levin, David G. Clark, and Howard R. Moskowitz
to accelerate ( Brazelton, 2013 ). Historically, many traits have been selected for in blueberry breeding programs with producers in mind, including climatic adaptation, yield, mechanical harvest potential, and disease resistance. Conversely, the
Sarah K. Taber and James W. Olmstead
a thumbnail, and contacting the pollen-loaded thumbnail to the stigma of the receiving flower. Hands were washed between pollinations. This methodology is routinely used within the University of Florida blueberry breeding program. For self
Jessica L. Gilbert, Michael L. Schwieterman, Thomas A. Colquhoun, David G. Clark, and James W. Olmstead
The University of Florida (UF) blueberry breeding program has been developing blueberry cultivars adapted to the subtropical Florida climate for over 60 years. During this time, many uncultivated Vaccinium species native to Florida were used as
Ann Marie Connor, James J. Luby, and Cindy B.S. Tong
Variation in antioxidant activity (AA), total phenolic content (TPH), and total anthocyanin content (ACY) was examined in 1998 and 1999 in fruit of 52 (49 blue-fruited and 3 pink-fruited) genotypes from a blueberry breeding population. The species ancestry included Vaccinium corymbosum L. (northern highbush blueberry), V. angustifolium Ait. (lowbush blueberry), V. constablaei Gray (mountain highbush blueberry), V. ashei Reade (rabbiteye blueberry), and V. myrtilloides Michx. (lowbush blueberry). Using a methyl linoleate oxidation assay (MeLO) on acidified methanolic extracts of the berries, a 5-fold variation was found in AA in 1998 and a 3-fold variation in 1999 among the blue-fruited genotypes. Analyses of variance (ANOVA) revealed variation among genotypes (P < 0.0001) in single and combined years, regardless of inclusion of pink-fruited selections and adjustment for berry size. While mean AA of all genotypes did not change between the 2 years, ranking of some genotypes for AA changed significantly between 1998 and 1999. Of the 10 genotypes that demonstrated the highest AA in 1998, four were among the 10 genotypes that demonstrated highest AA in 1999. Similarly, of the 15 genotypes with the highest AA, 10 were the same both years. As with AA, mean TPH of all genotypes did not change between years and ANOVA demonstrated genotypic variation regardless of adjustment for berry size/weight or exclusion of pink-fruited selections. Changes in genotype rank occurred between years. The difference in TPH between lowest- and highest-ranking blue-fruited genotypes was ≈2.6-fold in both 1998 and 1999. Seven of the 10 highest-ranking genotypes were the same both years and TPH correlated with AA (r = 0.92, P < 0.01) on a genotype mean basis for combined years. ACY correlated less well with AA (r = 0.73, P < 0.01 for combined years). When genotypes were categorized into six groups according to species ancestry, V. myrtilloides and V. constablaei × V. ashei crosses ranked highest and second highest, respectively, for AA in both years. The groups comprised of V. corymbosum genotypes, V. angustifolium genotypes, and those with both V. corymbosum and V. angustifolium in their lineage were indistinguishable from each other. Samples from some of the genotypes were analyzed for oxygen radical absorbance capacity and ferric-reducing antioxidant power, and these aqueous-based antioxidant assays correlated well with the lipid emulsion-based MeLO (all r ≥ 0.90, P < 0.01). The three antioxidant assays may be equally useful for screening in a blueberry breeding program and the choice of assay may depend on the goal of the program and the resources available.
James W. Olmstead, Hilda Patricia Rodríguez Armenta, and Paul M. Lyrene
a tool in blueberry breeding. The combination of a high level of similarity in chromosome morphology and frequent production of unreduced gametes has often been used to bridge ploidy barriers and introgress desirable traits from different species