For constructed treatment wetlands to effectively phytoremediate surface waters and wastewaters polluted with complex mixtures of recalcitrant and emerging organic pollutants, procedures for efficient enhancement in wetland plants are greatly needed. Tissue-culture induced variations provide a desirable alternative for plant enhancement; however, use of selective, tissue-culture induced variations for plant enhancement has not been explored in wetland plants. Therefore, the objective of this research is to determine the efficiency of tissue-culture induced variations in producing wetlands plants with enhanced phytoremediation capabilities utilizing Landoltia punctata (duckweed) and Typha latfolia (cattail) as model wetland plants.
The proposed research will evaluate the central hypothesis that inhibitory concentrations of organic pollutants during tissue culture of wetland plants will produce regenerated plants with enhanced phytoremediation capabilities. The rationale behind the proposed research is that development of wetland plants with enhanced phytoremediation capabilities will increase the capabilities of constructed treatment wetlands to reclaim polluted waters, improving ecosystem health while decreasing shortages of clean waters for human use.
The proposed research will evaluate the potential for tissue-culture induced variations to generate plants with enhanced phytoremediation capabilities, with the specific aims of:
(i) Evaluating the role of inhibition and pollutant exposure in producing L. punctata and T. latifolia tissue cultures with enhanced phytoremediation traits. (ii) Comparing enhancement of phytoremediation capabilities with regards to a model organic pollutant (3-trifluoromethylphenol) in tissue cultures and whole plants regenerated from tissue cultures on inhibitory and non-inhibitory media. (iii) Assessing phytotoxicity, uptake, and phytometabolism of halogenated phenols in plants with enhanced phytoremediation capabilities for 3-trifluoromethylphenol to evaluate whether enhanced plants possess enhanced phytoremediation capabilities for multiple pollutants.
The research will employ methods to evaluate decreased susceptibility to inhibition and increased rates of uptake and phytometabolism to assess phytoremediation capabilities of tissues cultures and whole plants resulting from tissue-culture induced variations under inhibitory and non-inhibitory conditions.
The proposed research is original by capitalizing on the link between detoxification and phytometabolism of organic pollutants to create a broadly-applicable method for enhancing wetland plants for phytoremediation that does not include genetic engineering, thereby increasing the potential applicability of the produced plants. Research is expected to yield the following outcomes: (i) L. punctata and T. latifolia plants with enhanced phytoremediation capabilities, (ii) protocols for enhancement of wetland plants via tissue-culture induced variations that can be expanded to include a broad range of organic pollutants and plant species, and (iii) valuable knowledge on effects of inhibition, pollutant exposure, and species on producing plants with enhanced phytoremediation capabilities.
Overall, the research is significant because it creates a new approach to enhance wetland plants for phytoremediation with implications for design of innovative wetland systems for treatment of organic pollutants.
The research will broadly impact society and science through integrating discovery and teaching, engaging underrepresented groups, broadly disseminating results, and addressing environmental and social challenges. The research will engage and train one graduate student and at least two undergraduate students in active research that transcends engineering and biology, while developing instructional materials on plant tissue culture for environmental engineers to promote interdisciplinary learning. This project will involve "undecided" female engineering students in research to encourage commitment to and development of engineering careers. Research and educational outcomes will be broadly disseminated through academic avenues, including journal publications and conferences, and public avenues, including networking with Michigan environmental consultants and publishing of educational outcomes through publicly-accessible services. Finally, by reducing barriers to adoption of enhanced wetland plants in constructed treatment wetlands, proposed research will attend to three eminent environmental and societal challenges ? shortages of clean water for society and ecosystems, increasing energy costs and greenhouse gases associated with wastewater treatment, and trace contamination of surface waters with emerging pollutants
