Bestrijding van Lyprauta cambria met ge-encapsuleerde insectparasitaire aaltjes

The aim of this project was to develop and test an ‘attract- and kill’ method for the larvae of Lyprauta cambria, a pest in Phalaenopsis orchids, on the basis of hydrocolloid-capsules with entomopathogenic nematodes. Capsules with 3 species of nematodes have been tested. Based on controlled laboratory experiments it has been shown that a) L. cambria larvae eat from Nema-Caps alginate-capsules, b) transfer of entomopathogenic nematodes from the Nema-Caps capsules to Lyprauta cambria could take place, and c) the effect of Nema-Caps hydrocolloid-capsules with entomopathogenic nematodes on L. cambria mortality was variable. Capsules with a high concentration of Steinernema carpocapsae nematodes seem to offer the best perspective. Moreover, is was found that at laboratory scale, at high RH and a temperature of 28°C, living nematodes emerged from the Nema- Caps for a period of at least 2 weeks (Heterorhabditis bacteriophora) or at least 3 weeks (Steinernema feltiae and S. carpocapsae). In a commercial greenhouse, Nema-Caps capsules that were spread over the surface of the bark remained on the surface after overhead irrigation, where they quickly dried out. Four days after overhead irrigation no living nematodes could be detected both at the surface and inside these capsules. Solving this problem is necessary before the capsules can be applied at greenhouse-scale.