Survey of the Trematode Parasites of Two Pulmonate Snails, Micromenetus dilatatus and Physa gyrina, From a Retention Pond in Gwinnett County, Georgia
We surveyed the trematode parasites of two pulmonate snails, Micromenetus dilatatus and Physa gyrina, from a retention pond adjacent Georgia Gwinnett College. Snails were collected from February to October 2013, and isolated in 5 ml wells of aged tap water. Within 48 hrs, snails were checked for shedding cercariae, which were identified to morphotype. Data showed prevalence greater in M. dilatatus (44%)than P. gyrina (5%). We recovered 7 cercariae and 2 metacercariae morphotypes. Micromenetus dilatatus was the most abundant snail during winter and early spring, but its abundance declined sharply in late spring and summer and none were collected in fall. Trematode prevalence was high in winter and early spring and peaked in April (75%). We collected 5 cercariae morphotypes and 1 metacercaria. Physa gyrina was collected throughout the survey, most commonly in February and October. This snail was host to 6 cercariae morphotypes and 1 metacercaria. Snails were not infected in winter, and although trematode prevalence peaked in May (10.5%), in October snails harbored a more species rich trematode community. Most common cercaria overall, and in M. dilatatus, was an ArmateXiphidiocercaria. This morphotype belongs to trematodes in the families: Telorchiidae, Plagiochiidae, Auridistomidae, Ochetosomatidae, and Cephalogonimidae and, as adults, they infect amphibians and reptiles. A Brevifurcate-Apharyngeate Furcocercous cercaria was the most common parasite in P. gyrina and belongs to trematodes in families: SpirorchiidaeandSchistosomatidaewhich as adults infect reptiles, and birds/mammals, respectively.
School of Science and Technology, Georgia Gwinnett College, Lawrenceville, GA 30043
P180 • Elliot J. Boerman, Melba Horton
Carbon Dioxide Uptake of Various Brassica oleraceae Cultivars
Cultivars of the Brassica oleraceae species form an important part of the human food crop since ancient time. Brussels sprouts, broccoli, and kale are members of the Acephala, Italica, and Gemmifera groups, respectively that have been shown to provide essential nutrients that are linked to reduce the risk of human cancers. The primary objective of this study is to determine if there is a significant difference between these cultivars in their carbon dioxide utilization. It is hypothesized that the different cultivars don’t vary in their CO2 uptake. To test this hypothesis, an experiment was conducted. Each plant cultivar (~6 week old seedling) was placed in a sealed container with a CO2 meter used to measure the changes in CO2 at 10 minute interval for an hour. This was repeated 3x with a new plant used each time to serve as replicates. The CO2 content of the sealed container without plants was also measured to serve as control. Using analysis of variance (ANOVA), results of the experiment indicated that Brussels sprouts consumed the highest amount of CO2 within an hour, followed by broccoli, and the least uptake by kale (p<0.05). This rejected the null hypothesis indicating that the three cultivars from the same parent population of wild mustard vary in their CO2 uptake. This implies that the cultivars are manifesting physiological variability and whether this is an adaptation that has some evolutionary implications needs further investigation.
Biology, University of North Georgia, Dahlonega, GA
P181 • Megan F. Brinkerhoff, Melba Horton
Effect of Varying Light Exposure on House Mice (Mus musculus) Food Consumption
The common house mice, Mus musculus, are nocturnal animals which exhibit sensitivity to light. Mice infestations and the damage they bring to properties and more importantly to human health had been widely reported. This experiment was conducted to determine the effect of varying light exposure on house mice to their food consumption. It is hypothesized that the amount of light exposure has no effect on the amount of food consumed by house mice. To test this hypothesis, three mice of approximately the same size were placed in each of three cages. One cage was exposed for 8 hours, and the other 2 for 12 and 20 hours of light a day for two days. After each exposure period, the cages were covered with black cloth to ensure total darkness. Each cage was provided 24 grams of commercially purchased mice food. At the end of the 2-day light exposure period, the remaining food was weighed and the difference was used as the total food consumed. Results of the T-test showed that mice exposed for 20 hours of light consumed significantly the least amount of food (p<0.05) while those in 8 and 12 hours did not show a significant difference (p>0.05). It is therefore concluded that the food consumption of house mice is significantly affected by light exposure which ultimately rejects the null hypothesis. This implies that lighted areas will probably have lesser likelihood of damage caused by mice infestation than darker environments.
University of North Georgia
P182 • Miranda N. Dey, Caleb W. Phillips, Benjamin R. Montgomery
Petals Abscise Earlier Under Hot, Dry Conditions for Linum rigidum , a Dry Prairie Species
Linum rigidum (stiff flax) is a small plant which grows in moisture limited habitats, but it has large petals that may substantially increase water loss. Perhaps, as a consequence, the corolla typically abscises in the afternoon, a few hours after opening. Three studies were conducted in order to examine the effect of weather conditions on time of petal abscission. First, we used a fan in a screen-house with little natural breeze to test the effect of wind speed (0, 3, or 6 m/s) on the time of petal abscission. The study did not show a significant influence of wind speed but did suggest an effect of humidity. Next, we found that in a humidity-controlled growth chamber, petals abscised earlier at low humidity (40%) than high humidity (80%). The third study investigated the relationship between petal abscission and natural variation in weather conditions including our wind study and two earlier studies in 2012 and 2013. Time of petal abscission was compared to several weather-related variables including temperature, relative humidity, and wind speed. We found that petals abscised earlier on hotter days, and there was some trend for petals to abscise earlier on dry days with high evaporative potential. Our data indicate that Linum rigidum petals abscise earlier under dry hot conditions, which suggests that early petal abscission functions to reduce water loss.
Division of Natural Sciences and Engineering, University of South Carolina Upstate, Spartanburg, South Carolina
