Warren A. Dick

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The dynamics of soil organic carbon (SOC) play an important role in long-term ecosystem productivity and the global C cycle. We used extended laboratory incubation and acid hydrolysis to analytically determine SOC pool sizes and ̄uxes in US Corn Belt soils derived from both forest and prairie vegetation. Measurement of the natural abundance of C made it(More)
ABSTRACT A biocontrol agent-fortified compost mix, suppressive to several diseases caused by soilborne plant pathogens, induced systemic acquired resistance (SAR) in cucumber against anthracnose caused by Colletotrichum orbiculare and in Arabidopsis against bacterial speck caused by Pseudomonas syringae pv. maculicola KD4326. A peat mix conducive to(More)
Rhodococcus strains were screened for their ability to degrade the herbicide atrazine. Only rhodococci that degrade the herbicide EPTC (s-ethyl-dipropylthiocarbamate) metabolized atrazine. Rhodococcus strain TE1 metabolized atrazine under aerobic conditions to produce deethyl- and deisopropylatrazine, which were not degraded further and which accumulated in(More)
Flue gas desulfurization (FGD) by-products are created when coal is burned and SO2 is removed from the flue gases. These FGD by-products are often alkaline and contain many nutrients including S. Agricultural application of FGD by-products is encouraged but little information is available related to plant responses and environmental impacts concerning such(More)
The genetic studies of metabolically diverse Rhodococcus spp. have been hampered by the lack of a system of introducing exogenous DNA. The authors improved an existing Escherichia coli-Rhodococcus shuttle vector (pMVS301) by removing much of the DNA not needed for replication and adding a multicloning site. This improved vector (pBS305) is 7.9 kb in length.(More)
Sterol acquisition by soilborne plant pathogens of the genus Phytophthora is presumed to involve extracellular proteins belonging to class-I elicitins. However, little is known about the relationship between sterol availability and elicitin secretion. The objective of this study was to determine the expression of class-I elicitin genes in Phytophthora sojae(More)
A thorough understanding of how conservation tillage in ̄uences water quality is predicated on knowledge of how tillage affects water movement. This paper summarizes the effects of conservation tillage on water movement and quality mainly based on long-term experiments on Luvisols at the North Appalachian Experimental Watershed near Coshocton, OH, USA.(More)
Microorganisms are an integral part of the biogeochemical processes in wetlands, yet microbial communities in sediments within constructed wetlands receiving acid mine drainage (AMD) are only poorly understood. The purpose of this study was to characterize the microbial diversity and abundance in a wetland receiving AMD using fluorescence in situ(More)
Most waterborne outbreaks of cryptosporidiosis have been attributed to agricultural sources due to the high prevalence of Cryptosporidium oocysts in animal wastes and manure spreading on farmlands. No-till, an effective conservation practice, often results in soil having higher water infiltration and percolation rates than conventional tillage. We treated(More)
Nitrate (NO3±N) commonly accumulates in soils because of fertilizer additions or when crop demand is much less than the rate of NO3±N production. Water table management (WTM) has been proposed to stimulate denitrifying bacteria, thus removing the accumulated NO3±N by converting it to N2O (a greenhouse gas) and N2. We studied the emission of N2O and N2 as(More)