2012 Annual Report
ARS scientists at Beltsville, Maryland continued to add DNA markers to the genetic map of blueberry and evaluated the entire mapping population for chilling requirement for the second year.
An ARS scientist at Beltsville, Maryland began studies to investigate gene flow (movement of pollen by bees) in lowbush blueberry as a possible explanation for yield differences among plants. One hypothesis is that honeybees may tend to move pollen short distances, thus they may be more likely to pollinate flowers from the same plant from which the pollen came or flowers from neighboring plants. If plants that are near each other are more likely to be closely related, then crossing these plants could result in seeds being too inbred to survive and yield fruit. Open-pollinated fruit from several plants were collected and the seed was germinated. The DNA from the seedlings, the mother plants, and the nearest 5 potential father plants were fingerprinted in an attempt to determine the most likely father for each seedling. This paternity analysis is ongoing and should establish whether bees are more likely to cross flowers in close proximity to one another or to flowers further away.
ARS scientists at Beltsville, Maryland, together with scientists at the University of Maryland and Towson University in Baltimore, Maryland have obtained about 500 million short sequences representing genes that are expressed in 4 different stages of diploid strawberry carpel development, about 250 million sequences from four stages of developing receptacle cortex, and about 100 million sequences from 3 early stages of embryo development. About 100 million sequences were also obtained from seedlings and leaves.
ARS scientists at Beltsville, Maryland determined that a recessive mutation in a single gene results in production of runners by a non-runnering diploid strawberry plant.
ARS scientists at Beltsville, Maryland, together with scientists at the University of Maryland have profiled the carotenoids present in leaves and reproductive structures of diploid strawberry.
ARS scientists at Beltsville, Maryland continued to add markers to genetic maps of strawberry. Repeat fruiting was associated with two different unrelated chromosomes in the strawberry genome.
ARS scientists at Beltsville, Maryland, and Corvallis, Oregon, together with scientists at Oregon State University used molecular markers to show that existing black raspberry cultivars are closely related to each other, and that wild black raspberries contain many genes not present in current cultivars. This information indicates that progress for black raspberry cultivar development may be dependent on including the wild black raspberries in cross pollinations.
Rowland, L.J., Bell, D.J., Alkharouf, N., Bassil, N.V., Drummond, F., Beers, L., Buck, E., Finn, C.E., Graham, J., Mccallum, S., Hancock, J., Olmstead, J., Main, D. 2012. Generating genomic tools for blueberry improvement. International Journal of Fruit Science. 12:276-287. Bell, D.J., Rowland, L.J., Drummond, F.A. 2012. Does pollen "neighborhood" affect yield in lowbush blueberry (Vaccinium angustifolium Ait.)? International Journal of Fruit Science. 12:65-74. Buck, E., C., W., Hurst, R., Mcghie, T., Scalzo, J., Allan, A., Rowland, L.J., Bassil, N.V. 2012. Progress in blueberry research in New Zealand. International Journal of Fruit Science. 12:304-315. Bell, D.J., Drummond, F.A., Rowland, L.J. 2012. Evidence of functional gender polymorphisms in a population of the hermaphroditic lowbush blueberry (Vaccinium angustifolium). Botany. 90:393-399. Arora, R., Rowland, L.J. 2011. Research on winter-hardiness: deacclimation resistance, reacclimation ability, photoprotection strategies, and a cold acclimation protocol design. HortScience. 46:1070-1078. Dossett, M., Bassil, N.V., Lewers, K.S., Finn, C.E. 2012. Genetic diversity in wild and cultivated black raspberry evaluated by simple sequence repeat markers. Genetic Resources and Crop Evolution. DOI:10.1007/s10722-012-9809-8. Hollender, C., Geretz, A., Slovin, J.P., Liu, Z. 2011. Flower and early fruit development in a diploid strawberry, Fragaria vesca. Planta. 235(6):1123-1139. Mccallum, S., Woodhead, M., Jorgensen, L., Gordon, S., Brennan, R., Graham, J., Hackett, C., Rowland, L.J., Hancock, J., Olmstead, J., Bassil, N.V. 2012. Developing tools for long-term breeding of blueberry germplasm for UK production. International Journal of Fruit Science. 12:294-303. Bushakra, J.M., Stephens, J., Atmadjaja, A.N., Lewers, K.S., Symonds, V.V., Udall, J.A., Chagne, D., Buck, E.J., Gardiner, S.E. 2012. Construction of black (Rubus occidentalis) and red (R. idaeus) raspberry linkage maps and their comparison to the genomes of strawberry, apple, and peach. Theoretical and Applied Genetics. 125(2):311-327.