|Lindsey, Raymond -|
|MCGRATH, J MITCHELL|
Submitted to: American Society of Sugarbeet Technologists
Publication Type: Proceedings
Publication Acceptance Date: May 20, 2011
Publication Date: N/A
Technical Abstract: Emergence and stand establishment through the first 10 weeks after planting continue to be primary concerns of sugar beet growers worldwide. Our goal is to understand the genes and genetics of seedling vigor, with vigor defined here as the ability of seedlings to tolerate adverse environments. Ongoing work shows an apparent induction of vigor via hydrogen peroxide that results in mobilization of stored lipid reserves for heterotrophic growth in good emergers, and that exogenous hydrogen peroxide can rescue the adverse effects of NaCl stress on germination percentages. We used this method to screen a series of adapted and unadapted germplasm to identify for tolerance to NaCl during germination, and selected and enhanced a number of germplasms that perform reasonably well under ion toxicity stress, notably progeny derived from Ames 3051. Characterization of Ames 3051 progeny showed that germination was retarded in 75 mM or 150 mM NaCl relative to water or hydrogen peroxide, but final germination was not significantly affected. Candidate genes were identified from the literature that were shown to be involved in response(s) to salt stress, and their cognate genes were identified from sugar beet nucleotide sequence collections. These will have been used to examine differential gene expression during salt stress germination. Accumulation of small molecule metabolites (proline, glycine betaine) quantified via mass spectroscopy will help to characterize the mechanisms of salt stress tolerance in sugar beet.