Resumen

LOYA-RAMIREZ, José Guadalupe; GARCIA-HERNANDEZ, José Luis; ELLINGTON, John J.  y  THOMPSON, David V.. Impacto de la asociación de cultivos en la densidad de insectos hemípteros entomófagos. INCI [online]. 2003, vol.28, n.7, pp.415-420. ISSN 0378-1844.

The impact of interplanting crops with cotton (Gossypium hirsutum) on the density of predator hemipterans was evaluated. In addition, this work pretended to reach evidences of intraguild predation among the predators. The interplanting crops were canola (Brassica napus), alfalfa (Medicago sativa), hairy vetch (Vicia villosa) and sanfoin (Onobrychis viciifolia). Density values were given as average number of individuals in 30 linear meters (i/30m). Density was also evaluated in cotton plots under different treatments to control pink bollworm (Pectinophora gossypiela), which were applied in plots without interplanting crops. The interplanted crops promoted high densities of predators and a significant migration toward the intercropped cotton. Geocoris spp. showed its highest density in hairy vetch, with a gradual increment towards the final sampling date on both nymph and adult stages. Nabis spp. also showed its highest abundance in hairy vetch, as nymph at the beginning of the season, and as adult in the middle of the season, decreasing its density subsequently in all crops, but its density in the second half of the season was statistically higher in alfalfa and sanfoin. Orius spp. had its highest density in alfalfa during the whole season, except in the last sampling date, when it was higher in the intercropped cotton. A significant reduction of Orius spp. in relation to an increment of Geocoris spp., and other results, provide signs of intraguild predation from Geocoris spp. to Orius spp. and probably to Nabis spp. The treatment including chemical insecticide in cotton showed the lowest averages.

Palabras clave : Algodonero; Cultivos Intercalados; Depredadores; Hemíptera .