A field study was conducted in 2005 and 2006 to evaluate the impact and interaction of the herbivores <i>Cyrtobagous salviniae</i> Calder and Sands and <i>Samea multiplicalis</i> Guenee on common salvinia, <i>Salvinia minima</i> Baker in south Louisiana. It was a completely randomized experimental design in which treatments consisted of <i>C. salviniae</i> and <i>S. multiplicalis</i> feeding on common salvinia both independently and together along with a control.
Our study revealed that treatments consisting of <i>C. salviniae</i> and <i>S .multiplicalis</i> feeding both independently and together had a significant impact on the biomass of common salvinia. Sampling done in October of both 2005 and 2006 showed that the lowest biomass was recorded for the treatment with both <i>C. salviniae</i> and <i>S. multiplicalis</i>. There was also a significant treatment by month interaction with a linear decrease in biomass for the treatment consisting of feeding by both <i>C. salviniae</i> and <i>S. multiplicalis</i> in 2005. Also, biomass showed a quadratic trend for the treatment with only <i>S. multiplicalis</i> in 2005. Percentage terminal damage (PTD) and percentage mat green (PMG) showed a significant treatment effect and a significant treatment by month interaction in 2005. Also, PTD showed a significant treatment effect and a significant treatment by month interaction in 2006.
A field study was conducted in May of 2007 to document the foraging behavior of red imported fire ants (RIFA), <i>Solenopsis invicta</i> Buren, on common salvinia mats in flooded woodlands and dredged canals. RIFA mounds were found in flooded woodlands at the base of live trees and on dead tree stumps. The recruitment of RIFA to the bait stations was not uniform up to 100 m into the flooded woodlands and in most instances there was no linear relationship between distance from the levee and number of ants. Also, the recruitment at different times of the day was not the same. Results of this study provide evidence that RIFA forage extensively on common salvinia in both flooded woodlands and dredged canals, and could possibly have an adverse impact on the populations of native <i>S. multiplicalis</i> and also on the survival and establishment of <i>C. salviniae</i>.
| Identifer | oai:union.ndltd.org:LSU/oai:etd.lsu.edu:etd-07032007-112751 |
| Date | 03 July 2007 |
| Creators | Tewari, Sunil |
| Contributors | Seth J. Johnson, Michael J. Stout, Linda M. Hooper-Bui |
| Publisher | LSU |
| Source Sets | Louisiana State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lsu.edu/docs/available/etd-07032007-112751/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached herein a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to LSU or its agents the non-exclusive license to archive and make accessible, under the conditions specified below and in appropriate University policies, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
Page generated in 0.0015 seconds