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Article is Editor's Choice in Journal of Freshwater Ecology

May 13, 2013

An article entitled, " Influences of light intensity variations on growth characteristics of Myriophyllum aquaticum" was recently chosen as the Editor's Choice article in the lastest issue of Journal of Freshwater Ecology (Volume 28, Issue 2, 2013). The article was written by Drs. John Madsen and Ryan Wersal.

Dr. Madsen is Associate Extension/Research Professor in the Geosystems Research Institute (GRI) and the Department of Plant and Soil Sciences at Mississippi State University. Dr. Wersal is a former GRI researcher and Postdoctoral Associate and is now an Aquatic Plant Scientist at Lonza Microbial Control in Alpharetta, GA.

Below is the Abstract regarding their research and findings: DOI: 10.1080/02705060.2012.722067

Myriophyllum aquaticum is a heterophyllous plant that is native to South America and has been introduced to the United States. The reallocation of resources to emergent or submersed growth forms likely allows M. aquaticum to overcome changes in light availability and to invade different habitats. Our objective was to determine the effects of light availability on plant length, biomass allocation, and relative growth rate through replicated mesocosm experiments.

Myriophyllum aquaticum
was grown in full sunlight, 30%, 50%, and 70% shade in replicated treatments. Total plant length, emergent shoot length, submersed shoot length, and the total of number of emergent and submersed shoots were recorded. Plants were harvested and sorted into emergent shoots, submersed shoots, roots, and stolons, then dried and weighed to assess biomass allocation. After 12 weeks, biomass was different among shade treatments. Differences in plant mass were a result of greater plant growth in the 30% shade treatment. Total plant length was greatest in the 50% shade treatment with a reduction in plant length observed in full sunlight. Emergent shoot length was reduced in full sunlight, while an increase in submersed shoot length occurred in 70% shade. Our data suggest that intermediate light availability is optimal for M. aquaticum growth and that the growth of two leaf forms is a physiological response to changes in environmental conditions.