Summary of Research
Dr. Millner contributes 0.40 FTE to the Methyl Bromide Project (1265-21220-176) within SASL, and 0.40 FTE to the Animal Waste Pathogen Lab. Methyl Bromide Project: Compost quality and reliability of disease suppression is a current barrier for widespread commercial use of composts by growers. Increased reliability of plant disease suppressiveness among batches of composts is being sought through targeted microbial augmentation coupled with process control management during compost curing. Compost, produced at the BARC composting research facility from our standard farm feedstocks, is inoculated with test BCs during curing in a lab-scale reactor which will provide control of aeration, temperature, and moisture so BCs are not destroyed by these factors. Preliminary evidence indicates that several BCs (Gliocladium virens, Talaromyces flavus) tolerate compost well enough to increase their populations during relatively short incubation periods. One deliverable will be a step-by-step protocol for quality-driven production of disease suppressive compost via managed curing. In addition, various means of compost placement and delivery to the root zone, rather than broadcasting across a field, are being examined in the context of other systemic changes in the strawberry production system. The overall goal is to develop a system that uses reduced inputs, increases net farm revenues, while building soil quality and biological buffering against ingress by root and foliar pathogens, pests, and weeds. Trials integrating these crop rotations with commercially available, resistant cultivars, biological control agents targeted against M. incognita on tomato, pepper, and strawberry (applied as root dips or drenches at transplant or fall runnering (berries), and custom composts and compost teas will be evaluated for suppression of M. incognita and root rots in field trials at Ft. Pierce, FL where organic production and strawberry system studies are in progress. Farming Systems Project: Management of organic matter amendments and especially their textural and water holding/filtering capacity on plant/soil/microbial interactions and dynamics will be compared in several intensively managed ecosystems: agricultural, urban rain gardens, and vegetated landfill covers. Enhanced carbon sequestration, reduced greenhouse gas emissions, and protection of water quality are desirable system functions that organic matter amendments can influence. Determining good construction, operation, and management practices requires additional knowledge about these functions. Research will focus on development and testing of organic matter blends that can enhance the desirable functions in each system through microbiorhizal activities.
Douds, D.D. Jr. and P.D. Millner. 1999. Biodiversity of arbuscular mycorrhizal fungi in agroecosystems. Agric. Ecosys. Environ. 74: 77-93.
Millner, P. and L. McConnell. 2000. Odor and Other Air Quality Issues Associated with Organic and Inorganic By-Products. Soil Science Society Special Publication.
Millner, P., S. Hogan, and J. Walker. 2000. A Guide to Recommended Practices for Field Storage of Biosolids and Other Organic By-Products used in Agriculture and Soil Resource Management, U.S. EPA, Office of Water, Division of Wastewater, Guidance Document 150 pp.
Thompson, W., P. Leege, P. Millner, and M. Watson. 2001. Test Methods for the Examination of Compost and Composting. USDA, Conservation Research Report (in press).
Millner, P.D., W.W. Mulbry, and S.R. Reynolds. 2001. Taxon Specific Oligonucleotide Primers for Detection of Glomus etunicatum Mycorrhiza 10:259-265.
Millner, P.D., W.W. Mulbry, and S.F. Reynolds. 2001. Taxon Specific Oligonucleotide Primers for Detection of Two Ancient Endomycorrhizal Fungi, Glomus occultum and Glomus brasilianum. FEMS Microbiology Letters Mar 15;196(2):165-70.
Buyer J., D. Roberts, P. Millner, and E. Russek-Cohen. 2001. Analysis of Fungal Communities by Sole Carbon Source Utilization Profile. J. Microbiological Methods 45:53-60.
Hakk, H., P. Millner, and G. Larsen. 2001. Fate of the Endogenous Hormones 17ß-Estradiol and Testosterone in Composted Manure, Proc., 2nd International Conference on Pharmaceuticals and Endocrine Disrupting Chemicals in Water sponsored by the National Ground Water Association, October 9-11, 2001. Minneapolis, MN.
Millner P.D. and S.F. Wright. 2002. New Molecular Tools to Determine the Presence and Activity of Arbuscular Mycorrhizal Fungi. Symbiosis.
Vanotti, M., et al. 2002. Evaluation of Polymer Solids Separation, Nitrification-Denitrification and Soluble P. Monograph (Spain).