Effect of vegetation cover on the biodiversity of arthropods associated with almond trees

Abstract

Almond production is an economically important activity in Portugal where both surface and production have shown a significant increase in the last decade. The almond tree is affected by several diseases and pests that can contribute to the quantitative and qualitative reduction of almond production. Biting-sucking pests (Hemiptera) such as monosteira, aphids, cicadelids, lepidopterans such as anarsia, grapholite, or coleopterans borers, such as capnode can cause, in some cases, significant damage. The aim of this study was to compare the abundance and functional diversity of arthropod communities in almond orchards using different weed management methods (displaced soil and presence of destroyed vegetation cover) in the Trás-os-Montes region. Cover crops had a significant effect on arthropod abundance and diversity. The orchard covered with vegetation (CCV) had the highest number of Araneae, Hemiptera and Neuroptera, while the orchard without vegetation cover (SCV) had the highest number of Coleoptera and Hymenoptera. Regarding the functional groups, the CCV orchard had a higher number of phytophagous and predatory arthropods, while no difference was observed between pollinators and fungivores. The diversity index was significantly higher in the presence of cover vegetation, which also showed greater dominance of hemipterans, namely the pest Monosteira unicostata.