BACKGROUND The planthopper Pentastiridius leporinus (Hemiptera: Cixiidae) is the main vector of the γ‐3 proteobacterium ‘Candidatus Arsenophonus phytopathogenicus’ which causes the syndrome ‘basses richesses’ (SBR) in sugar beet. SBR is a new and fast‐spreading disease in Central Europe that leads to high yield losses. To date, the development of management strategies has been hampered by insufficient knowledge about general life history traits of the planthopper and, most importantly, the year‐round availability of insects reared under controlled conditions. Rearing of P. leporinus has been considered challenging and to date no protocol exists. RESULTS Here we describe a method for mass rearing P. leporinus on sugar beet from egg to adult that has produced five generations and over 20 000 individuals between June 2020 and March 2022. An alternative host such as wheat is not necessary for completing the life cycle. No‐choice experiments showed that P. leporinus lays 139.1 ± 132.9 eggs on sugar beet, whereas no oviposition was observed on its nymphal host wheat. Head capsule width was identified as a trait that unequivocally distinguished the five nymphal instars. Developmental time from first instar to adult was 193.6 ± 35.8 days for males and 193.5 ± 59.2 days for females. Infection rates of adults were tested with a nested polymerase chain reaction. The results demonstrated that 70%–80% of reared planthoppers across all generations carried the SBR proteobacterium. CONCLUSION The mass‐rearing protocol and life history data will help overcome an important bottleneck in SBR research and enhance efforts in developing integrated pest management tools. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

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On the occurrence of predatory flies of the family Hypotidae (Dipt., Empidoidea) in greenhouses and on the predatory efficiency of two species of the genus Platypalpus Marquart This study provides an overview of the natural occurrence of predatory flies of the family Hypotidae in greenhouses using a reduced amount of pesticides. Five Platypalpus‐species, as well as T. arrogans L. and S. nubila Coll. completed their life cycle under glass. S. nubila was found to be a predator of Thysanoptera larvae. The predatory efficiency of two of the most common flies, P. minutus Meig. and P. annulatus Fall., was estimated as 2.4 individuals per day predator. Aphids and wasps were not killed. The activity during daytime increased continuously and reached a peak in late afternoon or early evening. The role of Hypotidae in the regulation of pests in greenhouses is discussed. Zusammenfassung Die Arbeit weist auf das natürliche Auftreten räuberischer Fliegen aus der Familie der Hypotidae in Glashäusern mit weitestgehendem Verzicht auf Pflanzenschutzmittel hin und gibt einen ersten Überblick über das vorgefundene Artenspektrum. Fünf Platypalpus‐Arten, T. arrogans und S. nubila etablierten sich über längere Zeiträume im Gewächshaus. Stilpon nubila konnte als Prädator von Thysanopteren nachgewiesen werden. Für die mit am häufigsten aufgetretenen Arten P. minutus und P. annulatus wurde eine prädatorische Leistung von 2,4 Individuen pro Räuber und Tag ermittelt. Blattläuse und Schlupfwespen wurden von P. annulatus nicht erbeutet. Die Beutefangaktivität stieg im Tagesverlauf kontinuierlich an und erreichte in den späten Nachmittags‐ und frühen Abendstunden ihren Höhepunkt. Die Bedeutung der Hypotiden für die Regulation von Schaderregern im Gewächshaus wird diskutiert.

“Syndrome des basses richesses” (SBR) is a sugar beet disease, which primarily leads to the reduction of sugar content and yield and thus to large economic losses. Two non culturable and vector transmitted pathogens, a proteobacterium („Candidatus Arsenophonus phytopathogenicus“) as well as a phytoplasma (“Candidatus Phytoplasma solani“) can cause SBR. SBR symptoms include chlorosis and necrosis of older leaves, necrosis of the vascular tissues of the beet and asymmetries of younger leaves. In 2018, it was shown that in addition to France Pentastiridius leporinus (L., 1761) it is the most important vector in Baden-Württemberg. This species has adapted from its natural host (reed) to the agricultural crop rotation of sugar beet and winter wheat. In 2018, P.leporinus was the most commonly caught Auchenorrhyncha species in sugar beet and 44% were loaded with the proteobacterium. The longest flight pattern of P. leporinus in sugar beet (from May 25th to September 5th) was detected. The first proof of a second generation led to the long flight pattern of this species. This article presents the development of the area of infestation and the proof of the two pathogens until 2018. In addition, previous findings as well as own results for the dissemination and control of SBR at Baden-Württemberg in 2018 are presented. Differences in susceptibility of sugar beet varieties were shown for the first time. One specific genotype showed no reduction in sugar content despite SBR infection. Variety selection could thus be a promising approach to control SBR in sugar beet.

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