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.
Zusammenfassung: Das Ziel der vorliegenden Arbeit war die Entwicklung, Reproduktion und Prädationsleistung zweier Raubthrips‐Arten Aeolothrips intermedius Bagnall (Thys., Aeolothripidae) und Franklinothrips vespiformis Crawford (Thys., Aeolothripidae) mit Ernährung zweier natürlicher Beutearten, dem Kalifornischen Blütenthrips Frankliniella occidentalis (Pergande) (Thys., Thripidae) und der Gemeinen Spinnmilbe Tetranychus urticae Koch (Acari: Tetranychidae) zu untersuchen. Die Arbeiten fanden unter standardisierten Klimabedingungen in modifizierten Gefäßeinheiten statt. Die Ergebnisse haben gezeigt, dass A. intermedius weder in der Lage war sich mit F. occidentalis‐Larven bzw. T. urticae‐Stadien zu entwickeln noch die Weibchen Eier ablegen konnten. Dagegen war F. vespiformis imstande sich in 23,6 Tagen mit F. occidentalis‐Larven und in 23,0 Tagen mit T. urticae‐Stadien als Beute vollständig zu entwickeln. Die durchschnittliche tägliche Eiablage lag bei F. vespiformis mit beiden Beutearten bei 0,67 Eiern. Im 18‐tägigen Versuchszeitraum legte ein Raubthrips‐Weibchen durchschnittlich 10,92 Eier mit F. occidentalis‐Larven und 10,58 Eier mit T. urticae‐Stadien als Beute. In der Prädationsleistung der beiden Raubthrips‐Arten zeigten sich signifikante Unterschiede mit F. occidentalis‐Larven als Beute. A. intermedius erbeutete täglich durchschnittlich 2,26 Schadthrips‐Larven, F. vespiformis dagegen 4,71. Im 18‐tägigen Versuchzeitraum verzehrte A. intermedius 20,83 Thripslarven und F. vespiformis mit 66,50. Mit T. urticae als Beute konnten keine signifikanten Unterschiede in der Prädationsleistung beider Raubthrips‐Arten beobachtet werden. Der Einsatz des Raubthrips F. vespiformis in einer Euphorbia milii‐Kultur unter praxisnahen Kulturbedingungen führte zu einer Reduktion der F. occidentalis‐Larven im Vergleich zur Kontrolle. Während der siebenwöchigen Versuchsdauer nach der Freilassung wurde in der Freilassungsvariante durchschnittlich eine F. occidentalis‐Larve/Blüte beobachtet, in der Kontrolle waren es dagegen 14 Larven/Blüte.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.