Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 11, 2002
Publication Date: June 23, 2002
Citation: Rowland, L.J., Ogden, E.L., Mehra, S. 2002. The search for molecular markers associated with cold tolerance in blueberry. Meeting Abstract. Technical Abstract: The blueberry industry in the United States suffers significant losses every year due to freezing stress. In fact, an increase in cold hardiness has been identified as one of the major needs of the blueberry industry. To address this need, our laboratory has been using two distinct but related approaches to identify molecular markers/genes associated with cold tolerance in blueberry. One approach has been to map QTLs controlling cold hardiness in the cold acclimated state. Progress toward mapping QTLs will be presented including: (1) construction of initial, low density genetic linkage maps for two diploid (V. darrowi x V. corymbosum-derived) blueberry populations segregating for cold hardiness; (2) use of PCR-based markers including RAPD and more recently EST markers for mapping purposes; (3) evaluation of the mapping populations for cold hardiness; and (4) genetic analyses of the cold hardiness data. The other approach has been to identify, isolate, and characterize cold-responsive genes from blueberry and to map these genes to determine if any map to QTLs that control cold hardiness. Levels of a group of dehydrin proteins (proteins induced by dehydration stress such as freezing and drought) of 65, 60, and 14 kDa increase during cold acclimation such that they become the most abundant proteins in blueberry floral buds during the winter. Progress using a systematic molecular genetic approach will be presented including: (1) characterization of expression of the dehydrins, (2) cloning members of the dehydrin gene family, (3) mapping members of the dehydrin gene family and (4) segregation of the dehydrin genes with the cold hardiness trait.