Distribución y fluctuaciones de las poblaciones de Liriomyza huidobrensis Blanchard (Díptera: Agromyzidae) y sus parasitoides en la Puna jujeña (NO argentino) Distribution and f luctuations of the populations of Liriomyza huidobrensis Blanchard (Díptera:

ORTIZ FELIX

Agraria

UNJu

Lugar: Jujuy; Año: 2006 vol. III p. 9 - 14

ABSTRACTLiriomyza huidobrensis Blanchard is a leafminer, polyphagous fly species thatdamages numerous vegetable and ornamental species.This species is widely distributed along the entire Quebrada de Humahuaca upto a 2940 m altitude. At higher altitudes ¡ts presence was only recorded in Abra Pampa.The purpose of this work was to expand knowledge on L. huidobrensis distribution inPuna and to evalúate its population fluctuations and the effects of its parasitoids on bean(Vicia faba L.) and pea (Pisum sativum L.), both very important crops as food sources forhuman populations of this área.The study was made on two plots sown with bean and pea free from chemicaltreatments, in Yavi Chico (659 25' W and 22- 05' S), at 3400 m.a.s.l. Two random monthlysamplings were made with the purpose of assessing adult and immature populations: a)10 plañís were shaken on tray containing 709 alcohol, and b) 30 folióles were extracted. L.huidobrensis and its parasitoids were recovered and quantified from the total number ofinsects obtained.L. huidobrensis occurs in the locality of Yavi Chico on bean and pea crops,especially on the first ones.The activity carried out by this Díptera is discernible from the plantule stage, inboth crops, with the appearance of feeding and reproduction punctures. Populationfluctuations remain below the economic relevance level.The parasitoid complex consists of microhymenoptera: Diglyphus sp. (Eulophidae),is the dominant species, while Chrysocharis flacilla (Walker) (Eulophidae), Halticopteraarduine (Walker) (Pteromalidae), and Opius scabriventris Nixon (Braconidae) were alsofound.The combined action of parasitoids and entomopathogens, where no chemicalproducís are being used, would account for Ihe fact that L. huidobrensis does not becomea pesl.