Floral and Faunal Species Diversity and Abundance of Aphid Predators in Ecological Apple Orchards

Abstract

ABSTRACT Faunistic and floristic characters of organic orchards with extensive and intensive vegetation management (mulching) were investigated. In the extensively mulched orchard more floral species were observed. Generally, in summer, flowering nectar-providing plants occurred only occasionally. Effects on species diversity and composition of the arthropod fauna on the trees was shown. In spring, diversity was higher in the extensive orchards, but this switched in July, when, in the intensive orchards, arthropods migrated on the trees. Aphid predators followed aphid population density. This may be due to the late occurrence of predators after a period of low temperatures in spring. Extensive mulching seems also to increase the abundance of Typhlocyba frogatti Baker (Cicadellidae).