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ARS Home » Plains Area » Fargo, North Dakota » Edward T. Schafer Agricultural Research Center » Insect Genetics and Biochemistry Research » Research » Publications at this Location » Publication #130340
Title: DNA BASED SPECIES IDENTIFICATION TEST FOR PARASITIC WASPS OF THE WHITEFLY

Author
item HEILMANN, LARRY - NORTH DAKOTA STATE UNIV
item ZHANG, JIANZHONG - NORTH DAKOTA STATE UNIV
item ANDRESS, EARL - USDA-APHIS, BRAWLEY, CA
item OLESON, ARLAND - NORTH DAKOTA STATE UNIV
item Nelson, Dennis
item GOULD, JULI - USDA-APHIS, PHOENIX, AZ
item CIOMPERLIK, MATTHEW - USDA-APHIS, MISSION, TX
item GOOLSBY, JOHN - USDA-APHIS, MISSION, TX
item VACEK, DON - USDA-APHIS, MISSION, TX

Submitted to: National Research and Action Plan for Silver Leaf Whitefly
Publication Type: Abstract Only
Publication Acceptance Date: 1/10/2002
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: A significant problem in using parasitic wasp species in biological control of the whitefly is identification of the individual wasp species parasi- tizing the nymph. This is particularly important in areas where imported foreign species are released. It is necessary to follow these releases to determine which species establish and reproduce, if they effectively parasitize local whitefly populations, and if they displace native parasi- toids. Current taxonomic tests for species identification are time consum- ing and require experienced and trained personnel. We have developed a simple and relatively quick DNA-based species identification test that can be applied to squashes of adult, pupal, and larval stage Eretmocerus and Encarsia wasps parasitizing whiteflies. The test utilizes highly repetitive but species-specific DNA sequences to identify the parasitizing wasp in one to two days. We currently have cloned DNA probes for Eretmocerus mundus (Spain), E.sp. (Ethiopia), E. hyati, and E. eremicus as well as Encarsia formosa and Encarsia sophia (transvena). The probes range from highly species-specific to only being selective for old world vs new world species. Each of the cloned probe DNAs has been sequenced and their dis- tribution in relevant parasitoid species quantified. In a major field test of the procedure, over 26,000 whitefly larvae from the Imperial Valley of California were squashed on filters and hybridized with the probes. These larvae were from multiple locations, multiple crops and different times of the year. Approximately 20% of these larvae were parasitized by the native California species, E. eremicus, with field variations ranging from 0 to 77%. Other imported species from Europe, Africa and Asia parasitized only 3-4% of the larvae. Results on this field test will be presented.