K L Bowen | PubMed Health

PubMed2005

Effect of environmental characteristics on Pythium and Mesocriconema spp. in golf course greens in Alabama.

The role the environment has on populations of Pythium and Mesocriconema spp. was investigated at 5 golf course locations in east central Alabama. Every 4 to 5 weeks soil samples were collected from 3 golf greens on each of the 5 golf courses. Environmental data, including air and soil temperature, pH and relative humidity, were also collected. Dilution plating and a combined sieving and sugar flotation procedure were conducted to determine the populations of Pythium and Mesocriconema spp. for each month. Isolates of Pythium from 4 months were also identified. Pythium spp. populations increased as soil temperature and ambient air temperature prior to sampling decreased (P < 0.05). Pythium spp. populations were highest in the winter and lowest in the spring. At some locations, populations of Mesocriconema spp. increased as soil acidity and populations of Pythium spp. decreased (P < 0.05) and as ambient air temperature prior to sampling increased (P < 0.05). Eight species of Pythium were isolated from 4 months, with Pythium rostratum being the most commonly isolated. Results suggest that Pythium and Mesocriconema spp. prefer different soil environments.

Alabama↗

PubMed1999

Validation of highly polymorphic fluorescent multiplex short tandem repeat systems using two generations of DNA sequencers.

Validation studies are a crucial requirement before implementation of new genetic typing systems for clinical diagnostics or forensic identity. Two different fluorescence-based multiplex DNA profiling systems composed of amelogenin, HumD21S11 and HumFGA (referred to as multiplex 1A), and HumD3S1358, HumD21S11 and HumFGA (multiplex 1B) have been evaluated for use in forensic identification using the Applied Biosystems Model 373A and Prism 377 DNA Sequencers, respectively. Experiments were aimed at defining the limit of target DNA required for reliable profiling, the level of degradation that would still permit amplification of the short tandem repeat (STR) loci examined, and the robustness of each locus in the multiplexes after samples were exposed to environmental insults. In addition, the specificity of the multiplexes was demonstrated using nonhuman DNAs. Forensically relevant samples such as cigarette butts, chewing gum, fingernails and envelope flaps were processed using both an organic extraction procedure and a QIAamp protocol. DNAs and resultant multiplex STR profiles were compared. The validation of the triplex STR systems was extended to include over 140 nonprobative casework specimens and was followed with a close monitoring of initial casework (over 300 exhibits). Our results document the robustness of these multiplex STR profiling systems which, when combined with other multiplex systems, could provide a power of discrimination of approximately 0.9999.

Animals↗