2013 Annual Report
1a.Objectives (from AD-416):
Increase collaboration with the Dipartimento Biotecnologie Agrarie in developing a program to better characterize the biology and physiology of sea beet, which is the most important genetic resource for enhancing beet production. Sea beet grows wild along the Adriatic Coast and has been studied by the Dipartimento Biotecnologie Agrarie in collaboration with Stazione Sperimentale di Bieticoltura di Rovigo (Sugar beet Experimental Station, Rovigo) for several years. We will.
1)identify populations to phenotype,.
2)enumerate traits selected for through domestication, and.
3)discover the genetic and genomic basis for these traits.
1b.Approach (from AD-416):
The USDA-ARS NPGS has an extensive collection of germplasm collected from the coast of Italy. Collaborative efforts with Dr. Enrico Biancardi, Prof. Massimo Saccomani, and Dr. Piergiorgio Stevanato, the foremost world experts in the life history of sea beet (Beta vulgaris subspecies maritima), have been initiated. We would work together to identify areas where NPGS collectors have collected sea beet germplasm, and measure population traits. These traits in sea beet would be compared with cultivated sugar beet and other domestic beets (table, fodder, Swiss chard) by both ARS and Italian researchers. Once phenotypic changes through domestication have been identified sea beet and domestic beet would be crossed to provide populations for genetic and genomic analyses. The gene and genomic changes brought about by the domestication process will be examined.
We have been working with collaborators in Italy to characterize germplasm for resistance to rhizomania (caused by Beet Necrotic Yellow Vein Virus – BNYVV), and using their SNP markers to estimate genetic distance within cultivated sugar beet and its crop wild relatives. Using the sea beet present in the Po Delta of Italy, our collaborators have developed SNP markers, which allow us to genotype the alleles present at two different disease resistance loci (Rz1 and Rz2) in our germplasm. These are the two major single gene resistance loci deployed in commercial germplasm. The resistance gene Rz1 has been used for close to 20 years and has been overcome by strains BNYVV in some growing areas. This has caused the Rz2 resistance gene to be deployed more frequently in commercial germplasm, either alone or stacked with Rz1. This collaboration is leading to the development of germplasm for resistance this disease carrying both resistance genes, as well as genetic stocks to allow genetic analyses of the effect of resistant and susceptible alleles at both loci.