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
 Invasive Plant Research Laboratory: Fort Lauderdale, FL
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    Outreach
                        Volunteer
                                    Outreach Activities 2019
                                    Outreach Activities 2020
                                    Outreach Activities 2022
                    K.I.N.D. GardenSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Southeast Area Fort Lauderdale, Florida Invasive Plant Research Laboratory 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
                                            Wheeler, Gregoryitem
                                            Center, Ted
  Submitted to: Environmental Entomology
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 12/5/2006
                                    Publication  Date: 4/16/2007
                                    Citation: Wheeler, G.S., Center, T.D. 2007. Hydrilla stems and tubers as hosts for three Bagous species: two introduced biological control agents (Bagous hydrillae and B. affinis) and one native species (B. restrictus). Environmental Entomology. 36(2):409-415.Interpretive Summary: The species Hydrilla verticillata is an invasive weed that threatens waterbodies throughout the southern US.  We studied the biological control of this weed by two weevils, a hydrilla tuber weevil Bagous affinis and hydrilla stem weevil B. hydrillae imported from India and Australia, respectively. Additionally, a native species, B. restrictus was found feeding on hydrilla at biological control release sites. Larvae of the hydrilla stem weevil could feed and survive as well on tubers as on stems. However, the same could not be said of the tuber weevil as larvae of this species could complete development only on tubers. These findings indicated that feeding on tubers by the hydrilla stem weevil may benefit the species particularly when hydrilla stems are seasonably absent or unsuitable especially in more northern climates.  In terms of hydrilla control, damage to tubers by this species constitutes a reduction in future infestations of hydrilla propagated by tubers.  Finally, hydrilla is suitable to the native weevil, B. restrictus as larvae completed development in hydrilla stems.
                                Technical Abstract: Field observations suggested that the introduced Hydrilla verticillata (L.f.) Royle biological control agent, a stem weevil Bagous hydrillae O’Brien would feed on dioecious hydrilla tubers as well as stems and a native species, Bagous restrictus LeConte would feed on hydrilla stems.  In choice tests the stem weevil B. hydrillae readily oviposited in hydrilla tubers.  Larval development of this species B. hydrillae in hydrilla tubers was similar to that in stems; greater adult biomass was attained and less time was required to complete development when the larvae were fed tubers.  Larvae of the hydrilla tuber weevil, B. affinis Hustache, did not complete development in hydrilla stems.  Larvae of the hydrilla tuber weevil, B. affinis, completed development more rapidly when fed new- compared with old-hydrilla tubers.  The native, B. restrictus successfully completed development in hydrilla stems, although the larvae required slightly more time compared with the biocontrol agent, the hydrilla stem weevil B. hydrillae.  These findings indicated that feeding on tubers by the hydrilla stem weevil may benefit the species particularly when hydrilla stems are seasonably absent or unsuitable especially in more northern climates.  In terms of hydrilla control, damage to tubers by this species constitutes a reduction in future infestations of hydrilla propagated by tubers.  Finally, hydrilla is suitable to the native weevil, B. restrictus as larvae completed development in hydrilla stems.


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