2007 Annual Report
1a.Objectives (from AD-416)
Test and release Diorhabda beetles from the Old World for biological control of saltcedar in Texas and monitor beetle reproduction, mortality and dispersal in the field. Measure the impact of feeding by Diorhabda beetles on growth and survival of saltcedar and the impact of biological control of saltcedar on native plant and animal communities. Investigate the use of additional exotic insects from the Old World for biological control of saltcedar in Texas. Obtain approval by FWS and USDA-APHIS and make multiple releases of the Diorhabda beetles throughout approved watersheds of Texas.
1b.Approach (from AD-416)
A combination of field and laboratory studies will be used to assess the population dynamics of newly released natural enemies of saltcedar. Estimates of population growth and dispersal will be assessed in combination with assessments of impact on the target plant population. Standard protocols of insect and plant monitoring will be followed as developed by the saltcedar consortium. GPS and GIS technologies will be used to help assess landscape level effects on the affected ecoystems.
3.Progress Report
This report documents research under a Specific Cooperative Agreement Number 58-6206-6-0014 between ARS and Texas A&M University, Texas Agricultural Extension Service, Dallas, Texas. Additional details of research can be found in the report for the parent project 6206-22000-006-00D, Biological Control of Saltcedar, Russian Olive, and Other Invasive Weeds in the Western USA. This Specific Cooperative Agreement was established to facilitate joint research between ARS Temple, TX, and Texas Agricultural Experiment Station, Dallas, on biological control of saltcedar. Funds expended during 2007 were used to support reserach in the Big Spring/Sweetwater, TX, area to develop optimal methodologies for releasing the Diorhabda beetles into the open environment. Factors influencing establishment after release appear to be site selection (simple ecosystem of saltcedar and light cover of grass or other vegetation, areas unlikely to flood, and areas unlikely to attract public notice appear best), time of year (earlier releases from April through first half of July), numbers to release (minimum of 500, or more), stage to release (young adults), and cage type or no cage (large cages until beetle population only moderately defoliates the enclosed saltcedar tree and reaches 500 adults). ADODR monitors this agreement through frequent e-mail, telephone and personal contact with the cooperator at the field sites and at workshops and planning meetings.
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