Moisture Source and Diet affect Development and Reproduction ofOrius thripoborusandOrius naivashae, two Predatory Anthocorids from Southern Africa

Abstract

The effect of moisture source and diet on the development and reproduction of the pirate bugs, Orius thripoborus (Hesse) and Orius naivashae (Poppius) (Hemiptera: Anthocoridae) was examined in the laboratory. Both species had been collected in and around sugarcane fields in South Africa. Supplementing eggs of the flour moth Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae) with a green bean pod as a moisture source yielded better nymphal survival and faster development, as compared with free water encapsulated in Parafilm, suggesting that the predators may extract extra nutrients from the bean pod. The impact of two factitious foods and moist honey bee pollen on developmental and reproductive parameters of both predators was also investigated. The overall performance of both Orius species on E. kuehniella eggs and cysts of brine shrimp, Artemia franciscana Kellogg (Crustacea: Artemiidae) was better than on pollen. Nonetheless, a pollen diet alone allowed 66 and 78% of the nymphs of O. thripoborus and O. naivashae, respectively, to reach adulthood. Overall, developmental and reproductive performance of O. thripoborus on the tested diets was superior to that of O. naivashae. The implications of these findings for the mass production of these predators and their potential role in biological control programs in southern Africa are discussed.

Thermal Biology of the Predatory BugsOrius thripoborusandO. naivashae(Hemiptera: Anthocoridae)

“…Although for O. thripoborus sex ratios at all temperatures were essentially 1:1, skewed sex ratios in O. naivashae observed by Bonte et al (2012) were conÞrmed in the current study. In the latter species, sex ratios were female biased, except at 23ЊC.…”

“…So far, it is not clear which mechanisms are involved in the female biased sex ratios observed in our O. naivashae population. Bonte et al (2012) reported a better lifetime oviposition of O. thripoborus at 23ЊC compared with that of O. naivashae. In the current study, fecundities and egg hatch rates were superior at 25ЊC for both species, and again, O. thripoborus produced more eggs than O. naivashae.…”

“…However, little information is available on the biology and ecology of Orius spp., which are native to the African continent. To optimize the mass production of O. thripoborus and O. naivashae for release in biological control programs, aspects of their nutritional ecology were investigated by Bonte et al (2012).…”

Eggs of Ephestia kuehniella and Ceratitis capitata, and motile stages of the astigmatid mites Tyrophagus putrescentiae and Carpoglyphus lactis as factitious foods for Orius spp.

“…This may be due to the different nutritional requirements of the immature versus adult stages of O. thripoborus , or to differences in their capacity to handle the astigmatid prey. Previous studies (Bonte et al ., , 2015) demonstrated a higher level of nutritional plasticity in O. thripoborus as compared with O. naivashae . This difference was confirmed on all tested foods in the present study, and was more pronounced on a less optimal prey, like the astigmatid mites.…”

Continuous rearing of the predatory anthocorid Orius laevigatus without plant materials

“…(Bonte and De Clercq , ; Bonte et al. ). The plants and artificial oviposition substrates were examined for eggs daily to determine the pre‐oviposition period.…”