Insect occurrence and losses due to phytophagous species in the amaranth Amaranthus hypocondriacus L. crop in Puebla, Mexico,

Abstract

A field survey for insects associated with amaranth Amaranthus hypocondriacus L. (Amaranthaceae) was conducted in the semiarid Region Mixteca of Puebla State in Mexico. Also, the losses to the crop caused by the phytophagous species were assessed. Samples were collected every fifteen days during one year in five plots to obtain a representation of the phytophagous and beneficial insects, and of the percentages of plants infested with the principal phytophagous insects. The species that were observed causing considerable damage to the crop were Hypolixus truncatulus Fab. (Coleoptera: Curculionidae), Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), Pholisora catullus (Fab.) (Lepidoptera: Hesperiidae) and Phyllophaga ilhuicaminai Morón (Coleoptera: Melolonthidae). Borers infested 92% of the crop, while the white grubs group 45%. Yield losses by general insects without pest control program were 65.5%. Foliage and soil insects reduced the yield to 44.2 and 39.1%, respectively. This is the first report of quantification of losses due to pest insects in the amaranth crop.