Opiine and Eucoiline parasitoids (Hymenoptera: Braconidae, Figitidae) of Anastrepha fraterculus (Diptera: Tephritidae) in the citrus orchard areas in Corrientes, Argentina.

OVRUSKI, S. M. Y P., SCHLISERMAN

The Canadian Entomologist

National Research Council Canada – Research Press (Revista de la Entomological Society of Canadá).

Lugar: Ottawa, Ontario; Año: 2003 vol. 135 p. 863 - 865

0008 347X

  Anastrepha fraterculus (Wiedemann), the South American fruit fly, and Ceratitis capitata (Wiedemann), the Mediterranean fruit fly, are the only economically important tephritid species present in the citrus-growing areas in the province of Corrientes, northeastern Argentina. The aim of this note is to more fully report on the hymenopterous parasitoid species reared from A. fraterculus, and provide preliminary information on natural parasitism levels in the fruit sampled.        Between January and March 1994, fruit samples of wild guava (P. guajava), Surinam cherry (Eugenia uniflora L.), and feijoa (Feijoa sellowiana (O.Berg) O.Berg) (all Myrtaceae) were collected in patches of disturbed wild vegetation adjacent to citrus orchards throughout the counties of Santa Lucía, Bella Vista, San Luis del Palmar, and Corrientes city.        The fruit samples consisted of fallen ripe fruit and ripe fruit still on the tree. Both fruit types were collected in similar proportions in each sample. A. fraterculus and C. capitata pupae were recovered weekly and separated using pupal characters (White and Elson-Harris 1992). The parasitization rate was calculated as the total number of parasitoids divided by the summed number of parasitoids and host flies emerging from a particular fruit sample. The infestation rate of each fruit species was calculated as the number of fly pupae per kg of fruit.        A total of 94 Neotropical parasitoids representing five species [Doryctobracon brasiliensis (Szépligeti), D. areolatus (Szépligeti), Opius bellus Gahan, Utetes anastrephae (Viereck) (all Hymenoptera: Braconidae, Opiinae), and Aganaspis pelleranoi (Brèthes)] were recovered from 1,117 A. fraterculus pupae which were obtained from 677 host fruits [371 (13.4 kg) guavas, 209 (1.3 kg) Surinam cherries, and 97 (1.5 kg) feijoas]. New fruit fly parasitoid species records for Corrientes Province are D. brasiliensis, U. anastrephae and O. bellus. Only 27 C. capitata pupae were recovered from all fruit species sampled. No parasitoids of C. capitata were recorded.         D. areolatus, U. anastrephae, and A. pelleranoi  were recovered from all host plant species sampled and they accounted for 45, 28, and 14% of all parasitoids, respectively. D. brasiliensis was the fourth most abundant parasitoid species (12% of all parasitoids obtained) and it was recovered from P. guajava and F. sellowiana. O. bellus, representing 1% of all emerged parasitoids, was only found attacking A. fraterculus larvae in P. guajava.        Although the data provided here are preliminary, this study show that native parasitoids associated with A. fraterculus are abundant in wild, native host plants. Interestingly, both D. areolatus and A. pelleranoi have considerable potential for the control of Anastrepha spp. in Latin America (Aluja 1999). We suggest that future A. fraterculus biological control strategies in Corrientes should be focused on patches of wild vegetation adjacent to commercial citrus orchards.