Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2001
Publication Date: 7/3/2001
Citation: Interpretive Summary:
Technical Abstract: Commercial use of metal hyperaccumulator plants requires domestication or creation of new crops which combine high biomass yield and high accumulation of soil metals in harvestable biomass. We have summarized the scientific aspects of this process, which include 1) selection of hyperaccumulating species likely to successful, 2) collection of diverse germplasm, 3) evaluation of the germplasm under valid conditions relevant to areas to be remediated, 4) breeding improved cultivars, and 5) development of agronomic practices needed to achieve effective phytoextraction. The latter includes determination of planting and harvest dates; methods for planting and harvest; fertilizer requirement for combined high biomass yield and metal phytoextraction; weed and pest control; density of plants for optimum yield; determination of annual vs. perennial management and other aspects of effective regrowth of harvested plants; and biomass processing requirements. The potential for the plant to become an invasive weed needs to be considered during selection of species for development. Methods to recover, or to safely dispose of, the metals in the harvested biomass must be demonstrated; some elements may have little economic value (e.g., Pb, As, Cd) at the concentrations achieved in biomass or even in ash of biomass, while phytomining other elements will become an alternative form of mining for some elements (Ni, Co). Genetic collections are critical to full understanding of these traits and their wise use.