Coleostephus myconis (L.) Rchb.f. role in conservation biological controlin an olive grove from Trás-os-Montes (Portugal)

Abstract: Currently, the management of agricultural habitats to optimize the action of naturalenemies is a form of conservation biological control. In this strategy, the reinforcement ofecological infrastructures can act as reservoirs for natural enemies, source of alternativefoods/hosts, and can provide shelter. In the olive grove, natural vegetation coverage istraditionally removed by tillage in order to avoid competition for water between olive trees andweeds. Nevertheless those plants could have an important role in natural control of crop pests. Inthis context, the objective of this work was to study the abundance of arthropods on arepresentative herbaceous plant, Coleostephus myconis (L.) Rchb.f., in two olive groves fromTrás-os-Montes (Northeast of Portugal). Fifty C. myconis specimens were weekly and randomlycollected during its flowering period. Afterwards, all arthropods found in the aerial part of theplant were sorted and identified under binocular microscopes to order or family level. Thirteenarthropod taxa were found on C. myconis. Abundance and diversity were higher in the Paradelagrove. The most abundant taxa were Aphididae and Thysanoptera. Coleoptera (larvae), Diptera(larvae) and Lepidoptera (larvae and pupae) orders were also found. Some of the recoveredgroups are important predators of olive pests which may have importance essentially during thedevelopment of the anthophagous generation of the olive moth, Prays oleae Bern.