Dr. Ernest Bernard, Professor
Research
The Great Smoky Mountains National Park All-Taxa Biodiversity Inventory (ATBI); taxonomy and ecology of Collembola, Protura, and nematodes; biological control of root-knot and cyst nematodes.
TITLE: All-Taxa Biodiversity Inventories (ATBIs) in Great Smoky Mountains National Park and other protected areas: Soil Arthropods and Nematodes.
Objectives: The goal of the ATBI is to document all known forms of life in Great Smoky Mountains National Park (GSMNP) and relate them ecologically to each other and their environments. This inventory is unprecedented in size and scope, with nearly 200 scientists and thousands of volunteers involved in documenting life in the Park. The Smokies constitute one of the most biodiverse temperate regions on earth. The best estimate is that 100,000 species of living organisms exist in the Park, but only a small fraction of these (vertebrates, butterflies, vascular plants) are well known. Most of these 100,000 species have not yet been recorded from GSMNP, and it is anticipated that many species new to science will be discovered. I serve as the taxonomic working group (TWIG) leader for the apterygote-myriapod TWIG (includes Collembola, Protura, Diplura, Thysanura, Microcoryphia, Pauropoda, Symphyla, Chilopoda, Diplopoda) and the nematode TWIG (includes free-living, plant-parasitic, and invertebrate-parasitic nematodes).
Currently, springtails (Collembola) are a major focus of this inventory work. Application of molecular techniques along with classic morphological studies is demonstrating that many species are in fact species complexes, comprised of several very similar but separate species with different niche requirements and distributions. Dr. Kevin Moulton of this department, former graduate student Kelly Felderhoff, and I have demonstrated that the very abundant and conspicuous genus Pogonognathellus is far more diverse than previously imagined. Before 2005, six species were listed for all of North America, but we have detected at least 13 species, most of them undescribed, in the southern Appalachians alone. Accurate determination of species is vital for understanding the ecology of these important members of the detrital food web.
Title: Biological Control of Root-Knot and Cyst Nematodes.
Objectives: Root-knot and cyst nematodes cause many millions of dollars worth of crop losses every year. For various reasons, means of control are quite limited. Biological control of these pests is an exciting possibility. Many kinds of soilborne fungi can attach these nematodes. The challenge is in finding and developing fungi that will attack nematodes at their most vulnerable stages and when they will have the most impact. Another approach is to use organic soil amendments or antagonistic plants to reduce nematode numbers. For instance, wheat planted in the winter reduces cyst nematode numbers so that the following soybean crop is less damaged. Also, plant residues (leaves, mulch) or their extracts (e.g., essential oils) mixed into soil can reduce nematode populations. (Essential oils are intensely aromatic, biologically active compounds found in a wide range of plants; one of the most familiar is peppermint.) As chemical management of nematodes fades into history, alternative approaches will become more important.
Essential oils are an exciting new approach to nematode management, indeed to many plant pathogens. I have been working with Dr. Kimberly Gwinn to quantify the effects of essential oils and the plants that make them on root-knot nematode survival. The plants we are studying include monarda (beebalm), epazote (a Chenopodium species used in traditional Mexican food preservation), and purple nutsedge, which appears to have an antagonistic effect on root-knot nematodes.
Check out the All-Taxa Biodiversity Inventory Dr. Bernard is working on in The Great Smoky Mountains National Park.
Read more about Dr. Bernard's research (USDA research reports) on the CRIS database at http://cwf.uvm.edu/cris/. Just choose CRIS Search and then enter Bernard, E. C. in the box marked Investigator.
Eastern Band of Cherokee Indians soil invertebrate survey.
Hemlock Wooly Adelgid, A Mortal Threat to Appalachian Hemlock Forests
The Hemlock Woolly Adelgid: A Threat to Hemlock in Tennessee (SP503-G)
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