The effects of brown stink bug, Euschistus servus (Say), and southern green stink bug, Nezara viridula (L.), feeding on pre-flowering, flowering, and senescing cotton, Gossypium hirsutum L., plants were evaluated in field studies. Vegetative stage seedlings and flower buds (squares) were not significantly injured by adults or nymphs of either species in no-choice studies. Brown stink bug adults induced boll abscission, and reduced seedcotton yield and seed germination in bolls accumulating T 350, T 550, and 101 to T 600 heat units beyond anthesis, respectively. In free-choice tests, boll preference was evaluated during each of the initial five weeks of flowering. Boll density increased from 5.1 to 6.6-fold from week one to week five. There was a corresponding 4.6 to 6.2-fold increase in total bolls injured. Boll injury ranged from 10.7% (week 4) to 27.4% (week 2) and 9.2% (week 3) to 16.0% (week 2) in 2002 and 2003, respectively. The frequency of injured bolls was highest for bolls accumulating 165.2 through 672 heat units beyond anthesis (1.161 to 3.586 cm diameter). However, brown stink bug significantly reduced seedcotton yields during weeks four and five due to the inability of cotton plants to compensate for injured bolls. Infestations of southern green stink bug during boll maturation, in combination with persistent rainfall and humidity, increased the proportion of rotted (2.0-fold) and ¡§hard locked¡¨ (1.4-fold) bolls compared to a non-infested treatment. Although stink bug injury was observed in hard locked (35.8%) and harvestable (20.3%) bolls, other abiotic and/or biotic factors are contributing to late-season harvest losses. In laboratory and field studies, the order of susceptibility (least to most) of stink bug species and life stages to insecticides commonly used for management was adult Euschistus spp. < late-instar nymphs < southern green stink bug adults. These studies defined brown stink bug and southern green stink bug to be significant pests of cotton during boll development stages. Stink bug management strategies should consider species, life stages, and the characteristics of specific insecticides.
| Identifer | oai:union.ndltd.org:LSU/oai:etd.lsu.edu:etd-06072004-171156 |
| Date | 08 June 2004 |
| Creators | Willrich, Melissa Marie |
| Contributors | Billy R. Leonard, James L. Griffin, Richard N. Story, Guy B. Padgett, Paul W. Wilson |
| 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-06072004-171156/ |
| 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. |
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