The use of ultraviolet-blocking films in insect pest management in the UK; effects on naturally occurring arthropod pest and natural enemy populations in a protected cucumber crop

Studies in polytunnels were conducted to investigate the effects of ultraviolet (UV)-blocking films on naturally occurring insect pests and their arthropod natural enemies on a cucumber crop. Within tunnels clad with Antibotrytis (blocks light < 400 nm) and UVI/EVA (UV transmitting), 5.8 and 23.4 times more aphids, respectively, were recorded on traps compared with those on traps within tunnels clad with XL 385 (blocks light < 385 nm). When all plants within the UVI/EVA tunnels had become heavily infested with aphids, half of the plants in XL 385 tunnels were uninfested. More Coleoptera and thrips (approximately two times) were recorded under the UVI/EVA film than under the UV-blocking films, but for other arthropod pests (e. g. whitefly, leafhoppers), clear conclusions could not be drawn as low numbers were recorded. Substantial numbers of chalcid parasitoids and syrphids were found under the UV-blocking films, but further research is needed to evaluate fully the effect of such films on biological control of aphids. Higher syrphid numbers and more aphid mummies were recorded under the UVI/EVA film, probably because of the higher numbers of aphids present in tunnels clad with this film. The potential that UV-blocking films have as an effective component of commercial Integrated Pest Management (IPM) systems, for protected horticultural crops, is discussed

Development and survival of Orius albidipennis and O. laevigatus (Het.: Anthocoridae) on various diets

The effect of various diets on nymphal development and survival of two predaceous anthocorid bugs, Orius albidipennis (Reuter) and O. laevigatus (Fieber) was investigated in the laboratory. Five different diets were Compared: eggs of Ephestia kuehniella Zeller; eggs of E. kuehniella plus mixed flower pollen; only mixed flower pollen; pollen from sweet pepper (Capsicum annuum L. cv. Mazurka) flowers; and sweet pepper plants. A high percentage of predators successfully completed nymphal development on those diets containing lepidopterous eggs. When fed on sweet pepper pollen, the survival percentages were 65% for O. laevigatus and 38% for O. albidipennis. No nymphs of either species completed the nymphal stage on mixed flower pollen or on sweet pepper plants. Development was significantly faster on diets containing eggs of E. kuehniella. Results are discussed in relation to the capability of the bugs to survive periods of prey scarcity and to the optimization of release strategies for these predators in the greenhouse