Postdoc Research Associate Virgina State University Petersburg, Virginia
Body of Abstract: With the increasing demands of locally grown produce and health perspective, urban agriculture (UA) is rapidly adopted across the United States. UA offers many benefits, however, it also presents its own concerns. One of the major concerns is the potential soil contaminations by heavy metals. Heavy metals, such as arsenic, become significant environmental pollutants, especially in urban areas. Removal of these polluted heavy metals from urban soils will not only reduce potential health risks due to direct exposures, but also benefit human health by bringing more clean arable lands to agriculture production. Purslane, P. oleracea, is a unique species that survives most severe abiotic stresses. In current study, we examined genetic variations among purslane accessions in response to arsenic. Significant genetic variation of shoot arsenic accumulation was observed among 9 accessions. While most accessions accumulated arsenic in their shoots between 50 to 150 mg/kg, accession Turkey accumulated more than 250mg/kg in its shoots. On the contrary, accessions TB and EG only accumulated less than 30 mg/kg arsenic. Further analysis indicated that arsenic transportation from roots to shoots was partially impaired in TB and EG. ABCC2, a known arsenic transporter gene in Arabidopsis, was cloned from Purslane. In consistent with phenotypic observations, the expression of PoABCC2 showed that it was highly induced in roots of arsenic susceptible accessions, but less induced in arsenic tolerance accessions. The results suggest a key role of PoABCC2 in arsenic root-to-shoot transportation in purslane and such function is different from its homologous gene in Arabidopsis (AtABCC2).