Oral Session 14—Fruit Breeding 28 July 2006, 4:15–5:15 p.m. Bayside A Moderator: David Byrne
Les Padley Jr. and Paul Lyrene
Jeffrey G. Williamson and William O. Cline
following topics are discussed: 1) use of sparkleberry ( V. arboreum ) in breeding to improve traits of southern highbush blueberry for mechanical harvesting; 2) effects of mechanical harvesting on postharvest quality of southern highbush blueberry; 3
W.A. Erb, A.D. Draper, and H.J. Swartz
Progenies and clones of interspecific hybrid blueberries were evaluated for annual fraction of canopy volume (FCYV) and for difference in fraction of canopy volume between control and stressed plants [FCYV(C) - FCYV(S)] in a moderate water-deficit environment. The FCYV(C) - FCYV(S) data were used to determine combining ability effects. In addition, physiological processes of attached leaves of the clones were monitored with a portable photosynthesis apparatus. Specific combining ability (SCA) effects were significant for FCYV(C) - FCYV(S). The clone with the lowest mean for FCYV(C) - FCYV(S) was US75, a hybrid of Vaccinium darrowi Camp × V. corymbosum L. Clone JU64 (V. myrsinites Lamark × V. angustifolium Aiton) also had a low FCYV(C) - FCYV(S) mean, and its two progenies (JU64 × JU11 and G362 × JU64) had low progeny means. Stomatal conductance was lowered when blueberries were exposed to atmospheric and/or soil moisture stress that resulted in lower transpiration and photosynthesis and increased or equal water-use efficiencies (WUE). Blueberry plants adjusted to moisture stress as the season progressed by lowering stomatal conductance and increasing WUE. In particular, stressed plants of US75 and JU64 had equal or higher WUE values than control plants. US226 was the most drought-susceptible clone in the study, and its stomata did not appear to be as responsive to moisture stress as the other clones. Breeding for higher WUE in a dry environment appears possible with the germplasm used in this study.
S.L. Noffsinger, A.D. Draper, and C.L. Gupton
Although southern highbush (Vaccinium sp.) is replacing rabbiteye (Vaccinium ashei L.) blueberry, rabbiteye will continue to be grown on marginal soils of the southeastern United States. Dwarfism or short, compact growth habit is a trait that could be used to reduce labor costs in rabbiteye blueberry production. Parental backgrounds, and flowering and fruit traits were studied in seven Mississippi (MS) and five Georgia (T) selections. Six of the MS selections are available for propagation and bloom late enough that cold damage should not be a problem. Four (MS63, MS454, MS546, MS891) of the six have acceptable fruit quality and will be used in breeding. Ethel and MS134 were the only known dwarf ancestors, with Ethel, Myers, Black Giant, and Tifblue (Ethel × Clara) dominating the parental background. Based on the variation in growth habit and ancestries, it would appear that Ethel has several genes for dwarfism and multiple allelic interactions are involved, similar to what Garvey and Lyrene found (1987). Future breeding will include crosses of MS63, MS454, MS546, and MS891 with germplasm outside of the common ancestors, to broaden the genetic base of the dwarf rabbiteyes.
Mark K. Ehlenfeldt, Filmore I. Meredith, and James R. Ballington
The fruit of six highbush (Vaccinium corymbosum L.) cultivars and eight rabbiteye (V. ashei Reade) cultivars and selections were evaluated by high-performance liquid chromatography for levels of the commonly found organic acids, citric, malic, succinic, and quinic. The two cultivar groups possessed distinctive patterns of relative organic acid proportions that could unambiguously separate pure rabbiteye and highbush clones in a principal component analysis. Highbush clones were characterized by high citric acid content, with percentages averaging 75% (range 38% to 90%). Succinic acid was the second most plentiful acid, averaging 17%. In contrast, rabbiteye cultivars and selections contained 10% citric acid, and no clone had >22%. Succinic acid and malic acid were found in greater quantities than in highbush, averaging 50% and 34%, respectively. Analysis of the fruit of seven albino-fruited highbush selections exhibited a profile similar to standard highbush cultivars, but with a citric acid average of <50%, and proportionally greater amounts of succinic and quinic acids. Given the differences in sensory quality of these four acids, it is likely that acid partitioning patterns can largely account for some of the perceived flavor differences between rabbiteye and highbush blueberries. Because several current breeding efforts involve hybridization between highbush and rabbiteye blueberries, a consideration of acid composition of breeding parents maybe worthwhile.
Chad E. Finn, Bernadine C. Strik, Theodore A. Mackey, Kim E. Hummer, and Robert R. Martin
-ARS) breeding program in Corvallis, OR, released in cooperation with Oregon State University’s Agricultural Experiment Station ( Finn, 2014 ). ‘Perpetua’ is the first strongly repeat fruiting (remontant, off-season, perpetual flowering) blueberry developed from
D. Scott NeSmith
). Vaccinium darrowii is typically compact in the wild and is often evergreen, whereas rabbiteye blueberries are typically deciduous and highly vigorous. Both V. darrowii and V. virgatum have been used for many years in breeding programs to develop hybrids
Andrew Raymond Jamieson
The expansion of the highbush blueberry (principally Vaccinium corymbosum L.) industry worldwide is supported by several successful breeding programs that have created cultivars with improvements in fruit size and firmness while retaining a
Ebrahiem Babiker, Stephen J. Stringer, Hamidou F. Sakhanokho, John J. Adamczyk Jr., and Arlen D. Draper
research and breeding purposes. Literature Cited Austin, M.E. Draper, A.D. 1983 ‘Brightwell’ rabbiteye blueberry HortScience 18 252 Ehlenfeldt, M.K. Finn, C.E. 2007 G-435 and ARS 96-138, pink-fruited blueberry selections HortScience 42 172 173 Ehlenfeldt, M
J.R. Ballington, C.M. Mainland, S.D. Duke, A.D. Draper, and G.J. Galletta
1 Professor. 2 Blueberry Breeding Researcher. 3 Research Geneticist, retired. 4 Research Geneticist. Paper no. 12206 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, NC 276967643. We express appreciation to