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Over the last decade, the sown area of quinoa (Chenopodium quinoa Willd.) has been increasingly expanding in Peru, and new production fields have emerged, stretching from the Andes to coastal areas. The fields at low altitudes have the potential to produce higher yields than those in the highlands. This study investigated the occurrence of insect pests and the natural enemies of quinoa in a traditional production zone, San Lorenzo (in the Andes), and in two new zones at lower altitudes, La Molina (on the coast) and Majes (in the &ldquo, Maritime Yunga&rdquo, ecoregion), by plant sampling and pitfall trapping. Our data indicated that the pest pressure in quinoa was higher at lower elevations than in the highlands. The major insect pest infesting quinoa at high densities in San Lorenzo was Eurysacca melanocampta, in La Molina, the major pests were E. melanocampta, Macrosiphum euphorbiae and Liriomyza huidobrensis, and in Majes, Frankliniella occidentalis was the most abundant pest. The natural enemy complex played an important role in controlling M. euphorbiae and L. huidobrensis by preventing pest resurgence. The findings of this study may assist quinoa producers (from the Andes and from regions at lower altitudes) in establishing better farming practices in the framework of integrated pest management.

International audience; Seasonal population dynamics of Brevicoryne brassicae (L.) and Diaeretiella rapae (McIntosh) were studied in two canola (Brassica napus) fields with two different irrigation methods (flooding and sprinkler irrigations) from April to June 2010. Aphid and parasitoid (mummies) populations were sampled once a week. The highest aphid density was recorded on May 12th (792.5 +/- 55.5) and on May 18th (1701.1 +/- 195) in the sprinkler and flood irrigated fields, respectively. Parasitism rate recorded ranged from 0.4 to 19.5% and from 1.0 to 11.9% in sprinkler and flood irrigated fields, respectively. During the course of the study, there was no significant relationship between the weather values recorded and aphid populations observed in the field. However relationship with weather values was found in the case of D. rapae populations. Secondary parasitism was higher at the end of growing season and two hyperparasitoid species were dominant: Pachyneuron aphidis (Bouche) and Alloxysta fuscicomis (Ashmead). We discuss role of seasonal parasitism and irrigation systems for management of B. brassicae.