Sauteri Poppius Research Articles

Is Orius sauteri Poppius a Promising Biological Control Agent for Walnut Aphids? An Assessment from the Laboratory to Field.

Walnut aphids are major pests of walnut production with few commercially available natural enemies. We conducted laboratory and field experiments to evaluate the potential of Orius sauteri Poppius (Anthocoridae), a predatory bug, as a biological control agent against two walnut aphid species: the dusky-veined aphid (Panaphis juglandis Goeze) and the walnut aphid (Chromaphis juglandicola Kaltenbach). Both species co-occur on walnut trees; P. juglandis is distributed on the upper surface (adaxial) of leaves while C. juglandicola is found on the lower surface (abaxial) of leaves. Based on functional response experiments, O sauteri had a strong capacity for consuming both aphid species. Biocontrol efficacy of O. sauteri for each species in the laboratory and field experiments was high, 77% for P. juglandis and 80% for C. juglandicola, regardless if one or two predators being present. However, biocontrol efficacy declined 15-25% for C. juglandicola and 20-50% for P. juglandis when both aphid species were present on the same leaf. The efficacy of O. sauteri under (semi)-field conditions gave similar findings based on the percentage reduction of aphids and change in population growth rates of aphids. The reduced biocontrol efficacy of the predatory bug against mixed species populations of aphids can be explained by competition between the aphid species and differences in their preferred location on leaves. Our experiments showed that O. sauteri is a promising biocontrol agent, but biocontrol efficacy may decline when both aphid species are present on walnut trees. This should be considered in the commercial release of O. sauteri in walnut orchards to promote economic and environmental benefits of walnuts production.

Annotated checklist of the plant bug tribe Mirini (Heteroptera: Miridae: Mirinae) recorded on the Korean Peninsula, with descriptions of three new species

An annotated checklist of the tribe Mirini (Miridae: Mirinae) recorded on the Korean peninsula is presented. A total of 113 species, including newly described and newly recorded species are recognized. Three new species, Apolygus hwasoonanus Oh, Yasunaga & Lee, sp. n., A. seonheulensis Oh, Yasunaga & Lee, sp. n. and Stenotus penniseticola Oh, Yasunaga & Lee, sp. n., are described. Eight species, Apolygus adustus (Jakovlev, 1876), Charagochilus (Charagochilus) longicornis Reuter, 1885, C. (C.) pallidicollis Zheng, 1990, Pinalitopsis rhodopotnia Yasunaga, Schwartz & ChĂŠrot, 2002, Philostephanus tibialis (Lu & Zheng, 1998), Rhabdomiris striatellus (Fabricius, 1794), Yamatolygus insulanus Yasunaga, 1992 and Y. pilosus Yasunaga, 1992 are reported for the first time from the Korean peninsula. Korean specimens previously identified as Eurystylus luteus Hsaio, 1941 are correctly recognized as E. sauteri Poppius, 1915. Three new synonyms are proposed: Apolygus atriclavus Kim & Jung, 2016 syn. n. of A. xanthomelas Yasunaga & Yasunaga, 2000, A. josifovi Kim & Jung, 2016 syn. n. of A. subpulchellus (Kerzhner, 1988) and Capsus koreanus Kim & Jung, 2015 syn. n. of C. wagneri Remane, 1950. Dorsal habitus photographs of the newly described or recorded species are presented along with figures of the genitalia of the new species. Keys to Korean genera and to species of Apolygus and Stenotus are provided. Zoogeography of the East Asian Mirini fauna is also discussed.

Review of the mirine plant bug genus Eurystylus Stål from Japan and Taiwan (Hemiptera: Heteroptera: Miridae: Mirinae), with descriptions of two new species, a new synonymy and a new combination.

Species of the Old World mirine plant bug genus Eurystylus Stål (the Head Bugs) in Japan and Taiwan are reviewed. Four species are currently recognized. Two new species are diagnosed and described: E. ryukyus n. sp. (from SW Japan and Taiwan) and E. jingfui n. sp. (Taiwan). Two known species, E. coelestialium (Kirkaldy) and E. sauteri Poppius, are diagnosed; new distributional records are added for the latter. Two keys are provided to aid the identifications of (1) Eurystylus and four related genera and (2) the species of Eurystylus known from Japan and Taiwan. The phylogenetic relationships of Eurystylus with the assumed related genera are discussed. Eurystylomorpha Poppius is synonymized with Eurystylopsis Poppius, and a new combination, Eurystylopsis crassicornis (Poppius), is accordingly proposed.

Effects of arbuscular mycorrhizal fungi on the abundance of foliar-feeding insects and their natural enemy

We investigated the effects of symbiotic association between a plant and an arbuscular mycorrhizal fungus (AMF) on the abundance of aboveground foliar-feeding insects that differed in feeding mode and their predator. We examined effects on insect abundance as the result of AMF-related changes in the quality and quantity of plants in the field. The numbers of three insects with different foliar-feeding mode (phloem feeder, chewer, and cell-content feeder) and their generalist predator Orius sauteri Poppius on soybean Glycine max (L.) Merrill with and without the AMF Gigaspora margarita Becker & Hall were compared over time. Symbiotic association between the AMF and the soybean increased shoot biomass, the concentration of phosphorus in the soybean, and the abundance of the phloem feeder Aulacorthum solani Kaltenbach, but did not affect the abundance of generalist chewers. In addition, the effects of the symbiotic association on the abundance of cell-content feeding Thrips spp. and the generalist predator O. sauteri differed between sample dates. These results indicated that the effects of the symbiotic association on the number of foliar-feeding insects depended on feeding mode and the number of predators.

The potential use of different predatory bug species in the biological control of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)

In the present study, the suitability of different predatory bug species, such as Dicyphus tamaninii Wagner, Macrolophus pygmaeus (Rambur), Orius albidipennis Reuter, Orius majusculus Reuter and Orius sauteri Poppius, for the biological control of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), were investigated. Development of the predatory bug species, their reproduction as well as their daily and total prey consumption over a 18-day period with F. occidentalis larvae or various stages of Tetranychus urticae Koch (Acari: Tetranychidae) individuals as prey species were studied during the experiments in the laboratory. In further experiments, the efficiency of D. tamaninii, M. pygmaeus, O. albidipennis and O. majusculus in controlling F. occidentalis under glasshouse conditions was investigated. Results showed that all the predators could develop under the experimental conditions with either F. occidentalis larvae or different stages of T. urticae as prey. When F. occidentalis larvae were offered as prey, the shortest duration of development was observed for O. albidipennis with a mean of 17.7 days, while D. tamaninii took the longest to develop with a mean of 36.3 days. With different stages of T. urticae as prey, the duration of development ranged from 19.3 days in O. albidipennis to 42.9 days in M. pygmaeus. Mean daily fecundity ranged from 0.8 eggs/female for O. majusculus to 2.2 eggs/female for O. sauteri with F. occidentalis larvae as prey and from 0.6, O. majusculus, to 2.3 eggs/female/day, O. sauteri, when different stages of T. urticae were offered as prey. Over the 18-day reproduction period, O. sauteri was the most fecund predatory species, laying a mean total of 31.6 and 31.3 eggs/female with F. occidentalis and T. urticae as prey, respectively. Daily consumption from F. occidentalis larvae ranged between 5.5 individuals consumed per day by O. majusculus and 29.1, by O. sauteri. When different stages of T. urticae were offered as prey, maximal consumption was observed in D. tamaninii with a mean of 29.0 individuals/day, while O. albidipennis consumed the least with an average of 8.1 preys/day. Over the 18-day prey consumption period, D. tamaninii consumed the highest mean number of 422.8 F. occidentalis larvae, while O. majusculus only consumed 98.8 larvae. Also, D. tamaninii had the maximum consumption of different stages of T. urticae with a mean of 522.4, while M. pygmaeus and O. albidipennis consumed the least, with an average of 146.1 and 146.0, respectively. The predatory bugs D. tamaninii, M. pygmaeus, O. albidipennis and O. majusculus significantly reduced the density of F. occidentalis on hybrids of Euphorbia milii, Serissa foetida and Saintpaulia ionantha in the glasshouse, which confirms their efficiency against this pest on different hosts under controlled climatic conditions.