MICROBIAL ECOLOGY OF AGRICULTURAL SYSTEMS

Health and Food Safety Implications of Organic vs. Conventional Management of Fruit Trees: Impact on Phyllosphere Microflora
Andrea R. Ottesen, James R. White, Chris Walsh, Jocelyne DiRuggiero, Michael Newell, Demetra Skaltsas, Kim Kroll


Using a statistically-significant, randomized complete block orchard planting at the Wye Research and Education Center, (a sustainable agriculture project supported by Agroecology and SARE), we study biological principles underlying the agricultural sustainability and health and food safety implications of Organic vs. Conventional crop management.

Our work focuses on streamlining logistics involved in managing “certified organic” crops while simultaneously investigating the impact of organic vs. conventional chemical applications on fruit and leaf surface bacterial microflora. Primary work has focused on Gram negative bacterial species because of their important role in human health issues (Enterobacteriaceae: E. coli, Salmonella, etc.) as well as the destructive impact of the Gram negative plant pathogen (Erwinia amylovora, "Fireblight") on apple and pear crops .

Detecting Contamination of Herbal Products Using  DNA “Barcoding” Regions: A Case Study with Star Anise (Illicium verum)
George C. Ziobro, (FDA), Andrea Ottesen, Huiling Zhou*, Demetra Skaltsas, Chris Walsh, (UMD)
*Department of Horitculture, Northwest Agriculture and Forestry University, Yangling, 712100, Shannxi,China

Seedpods of Illicium verum Hook f., (Star Anise), are used in the preparation of teas, herbal remedies, and culinary dishes. Adulteration by seedpods of other Illicium species poses a health risk due to elevated levels of neurotoxic compounds (veranisatins), such as anisatin and neoanisatin present in other Illicium species - specifically Illicium anisatum. Similarities in seedpod morphological characters preclude their use to definitively speciate individual seedpods. Our work reports on the analysis of multiple proposed "barcoding" /"biocoding" regions from plastid and nuclear DNA, to identify regions of significant difference that could be used as definitve markers to identify and distinguish between species.          

AMAZONIAN MEDICINAL PLANT RESEARCH
Andrea Ottesen, Jim Duke, Guierllmo Rodriguez Gomez

Toxic and medicinal properties of Amazonian and tropical medicinal plants.