Abstract

AVILA-RODRIGUEZ, V et al. Identification, population dynamics and parasitism of aphids in pecan in the Comarca Lagunera, Mexico. Phyton (B. Aires) [online]. 2016, vol.85, n.2, pp.249-255. ISSN 1851-5657.

Pecan Carya illinoinensis (Wang.) K. Koch is one of the most important crops in northern Mexico. In the Comarca Lagunera, during 2013, the pecan acre age was 7075 ha, a nut production of 8648 ton, and a value of US$ 29.9 million (US$ 4230/ha). The aphids Monellia caryella Fitch., Monelliopsis pecanis Bissell and Melanocallis caryaefoliae Davis (Hemiptera: Aphididae) are among the most important insect pests associated with the pecan. The objectives of this study were to identify the species of aphids, determine their population dynamics and parasitism, in pecan orchards with different insect pest management programs, in the Comarca Lagunera. Leaf samplings and aphid specimen collections were carried out from April to September 2012 in three pecan orchards, one with organic production, another one with a biorrational and the third one with conventional pest management programs. The aphid species identified were M. caryella, M. pecanis and M. caryaefoliae (Hemiptera: Aphididae). Yellow aphids (M. caryellaand M. pecanis), showed two periods of peak population in May-June and September. Black aphids showed only one population peak in September to the end of the crop cycle. The lowest populations of yellow and black aphids occurred in the pecan orchard with organic management. Parasitism was null in the yellow aphid, very low in the black margined aphid (0.3%) and greater in the black aphid (25.9%). The higher level of parasitism was in the pecan orchard with a conventional management program. Aphid parasitoids belonged to Aphelinidae (genus Aphytis), Eulophidae (genus Quadrasticus), Encyrtidae and Torymidae families (superfamily Chalcidoidea) and the Braconidae family (superfamily Ichneumonoidea).

Keywords : Pecan; Aphids; Population dynamics; Parasitism; Comarca Lagunera.