U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Spurgeon, Daleitem
                                            Sappington, Thomasitem
                                            RUMMEL, D. - RETIRED TEXAS A&M
  Submitted to: Southwestern Entomologist
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 4/28/2008
                                    Publication  Date: 7/23/2008
                                    Citation: Spurgeon, D.W., Sappington, T.W., and Rummel, D.R. 2008. Host-free Survival of Boll Weevils (Coleoptera: Curculionidae) from Two Regions of Texas. Southwest Entomol. 33:151-152.Interpretive Summary: The boll weevil overwinters in most U.S. cotton production areas in a state of dormancy called diapause. This diapause state permits the weevils to survive the non-cropping season without feeding on cotton. New information regarding diapause could be useful to efforts to improve the efficiency of ongoing eradication programs. Some reports have suggested that diapause is controlled differently in weevil populations from different geographical areas. However, more recent reports for two widely-separated weevil populations in Texas do not support these conclusions. In laboratory studies we stimulated weevils from the Lower Rio Grande Valley (LRGV) and High Plains of Texas to enter diapause by manipulating their food supply, and then compared their survival in the absence of food. Examinations of weevils at the beginning of the survival period indicated about 90% were in diapause.  Average (4 to 6 weeks) and maximum (12 to 16 weeks) survival was similar for the two weevil populations, and statistical tests did not indicate differences in their respective patterns of survival. Therefore, our results did not provide any evidence to suggest the diapause state differs between these two weevil populations. Our results also suggest that efforts to understand apparent differences in boll weevil overwintering between temperate and subtropical regions should focus on influences of the overwintering environment, such as weather, rather than on differences in diapause.
                                Technical Abstract: New information regarding boll weevil (Anthonomus grandis Boheman) overwintering, and especially diapause, is important to efforts to improve the efficiency of eradication programs. Some published reports suggest the diapause response differs among geographically separated populations of the boll weevil. However, recent experimental evidence failed to indicate such differences between two populations in Texas. We used dietary methods to induce diapause in weevils from the Lower Rio Grande Valley (LRGV) and High Plains of Texas, and compared their subsequent host-free survival under controlled conditions (23.9 +/- 1 degree C). Dissections confirmed high levels of diapause at the initiation of the host-free period (females, 91-98%; males, 84-93%). Survival analyses indicated median longevities of about 4 wk for High Plains weevils, and nearly 6 wk for weevils from the LRGV. Maximum longevities were 12 and 16 wks (LRGV and High Plains, respectively). No statistical differences were detected between survival curves for the two populations. Therefore, our results did not indicate fundamentally different responses to our experimental conditions by weevils from the Texas High Plains and LRGV. These results suggest that efforts to interpret apparent differences in the dynamics of boll weevil overwintering between temperate and subtropical regions should focus on influences of the overwintering environment rather than on differences in the diapause response.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov