Skip to main content
ARS Home » Research » Publications at this Location » Publication #214905
Title: Open-field host specificity test of Gratiana boliviana (Coleoptera:Chrysomelidae), a biological control agent of Tropical Soda Apple (Solanaceae) in the United States

Author
item GANDOLFO, DANIEL - USDA/ARS/SABCL
item MCKAY, FERNANDO - USDA/ARS/SABCL
item MEDAL, JULIO - UNIVERSITY OF FLORIDA
item CUDA, JIM - UNIVERSITY OF FLORIDA

Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/20/2007
Publication Date: 3/20/2007
Citation: Gandolfo, D.E., Mckay, F., Medal, J.C., Cuda, J.P. 2007. Open-field host specificity test of Gratiana boliviana (Coleoptera:Chrysomelidae), a biological control agent of Tropical Soda Apple (Solanaceae) in the United States. Florida Entomologist.V.90(1):223-228

Interpretive Summary: Tropical soda apple (TSA)is an invasive shrub native to southern South America (Argentina, Brazil, Paraguay and Uruguay), accidentally introduced into the USA at the beginning of the 1980s. Explorations conducted in South America for potential biological control agents of TSA, revealed the presence of a leaf feeding beetle. In the present study, we report the suitability of this South American leaf feeding beetle for biological control of Tropical Soda Apple (TSA) in the USA. One hundred adult beetles were released in two field plots, one containing TSA and the other containing eggplant. Forty additional beetles were released in the eggplant plot at the flowering stage. All the plants in each plot were checked twice a week and the number of adults, immatures, and eggs recorded. Results showed almost a complete rejection of eggplant by the leaf beetle. No noticeable feeding damage was ever recorded on eggplant. The results of this open-field experiment corroborate previous quarantine/laboratory studies indicating that the possibility of the leaf feeding beetle to include eggplant among its host plants is highly unlikely. The leaf feeding beetle was approved for field release in May 2003 in the USA. To date, no nontarget effects have been observed either on eggplant or native TSA related species.

Technical Abstract: An open-field experiment was conducted to asses the suitability of the South American leaf feeding beetle Gratiana boliviana Spaeth for biological control of Solanum viarum Dunal in the USA. An open-field test with eggplant, Solanum melongena L., was conducted on the campus of the University of Buenos Aires, Argentina, and a S. viarum control plot was estblished 40 km from the campus. One hundred adult beetles were released in each plot at the beginning of the experiment during the vegetative stage of the plants, and forty additional beetles were released in the S. melongena plot at the flowering stage. All the plants in each plot were checked twice a week and the number of adults, immatures, and eggs recorded. Results showed almost a complete rejection of eggplant by G. boliviana. No noticeable feeding damage was ever recorded on eggplant. The experiment was ended when the eggplants started to senesce or were severely damaged by whiteflies and spider mites. The results of this open-field experiment corroborate previous quarantine/laboratory host-specificity tests indicating that a host range expasnion of G. boliviana to include eggplant is highly unlikely. Gratiana boliviana was approved for field release in May 2003 in the USA. To date, no non target effects have been observed either on eggplant or native species of Solanum.