Avocado thrips, Scirtothrips perseae (Thysanoptera: Thripidae), is the most serious pest attacking avocados in California, USA. Laboratory work has indicated that up to 77% of second instar S. perseae larvae fall or jump from branches to pupate beneath host trees. One potential control strategy for reducing S. perseae densities could be to adversely affect pupation rates beneath trees by creating an environment hostile to thrips propupae and pupae thereby reducing adult thrips emergence rates. We have been investigating the efficacy of composted organic yard waste which is used for the biological control of Phytophthora cinnamomi in avocado orchards for control of S. perseae. Results from one years field trials indicates that peak emergence rates of S. perseae can be reduced by approximately 50% under trees that are mulched in comparison to non-mulched control trees. Furthermore, the pupation rates of Franklinothrips orizabensis (Thysanoptera: Aeolothripidae), the key natural enemy of S. perseae, are not adversely affected even though >90% of larvae of this species pupate beneath host trees. Companion studies are investigating potential suppressive mechanisms which may include antagonistic microarthropods, and entomopathogeic fungi and nematodes that colonize composted mulch but could be absent from naturally occurring avocado leaf duff.
Species 1: Thysanoptera Thripidae Scirtothrips perseae (avocado thrips)
Species 2: Thysanoptera Aeolothripidae Franklinothrips orizabensis
Species 3: Laurales Lauraceae Persea americana (avocado)
Keywords: cultural control
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA