Jiri Skuhrovec

Crop Research Institute · Function of Invertebrate and Plant Biodiversity in Agro-Ecosystems

We envisage a future research environment where digital data on species interactions are easily accessible and comprehensively cover all species, life stages and habitats. To achieve this goal, we need data from many sources, including the largely untapped potential of citizen science for mobilising and utilising existing information on species int...

Drought affects both crops and their pests, but the effect of the interaction between drought and pests on crops has not been sufficiently understood. The aim of this work is to determine (i) the response of spring wheat (Triticum aestivum) to three watering regimes (soil water capacity of 70, 50 and 40%) and aphid (Metopolophium dirhodum) infestat...

In the field, plants usually have to face the combined effects of abiotic and biotic stresses. In our study, two spring wheat cultivars—Septima and Quintus—were subjected to three water regimes [70%, 50%, and 40% soil water capacity (SWC)], aphid ( Metopolophium dirhodum ) infestation, or the combination of both stresses, i.e., water deficit (50%,...

This paper follows the first part of the annotated checklist of weevils (Coleoptera: Curculionoidea excepting Scolytinae and Platypodinae; ‘exSP’ below) of the Czech Republic and Slovakia, published by Benedikt et al. in 2010. The introductory chapter presents a new checklist following the current system and nomenclature of Curculionoidea (Alonso-Z...

The present catalogue is an improved and updated edition of the one published in November 2017.It contains 1627 valid genera, 681 valid subgenera, 15,531 valid species, 1,013 valid subspecies and9,098 names of invalid or nomenclaturally unavailable species-group taxa belonging to the sevenfamilies of Coleoptera Curculionoidea recognised in the Pala...

Ladybirds (Coleoptera: Coccinellidae) are an important beneficial group that, as other insects, are negatively affected by many human-mediated threats, including climate change, agricultural intensification, habitat loss, pollution, and biological invasions. Ecological impacts from these threats have altered the richness, abundance, and distributio...

The gregarious parasitoid strategy allows multiple larvae to complete development in a single host due to their tolerance and/or lower mobility, and thus flexibly adjust their reproductive potential. Reproductive potential is traditionally measured as the number of each mother’s offspring. In our previous study we showed the benefits of an intergen...

Cílem metodiky je popsat způsob stanovení zón v polní pěstitelské praxi pomocí různých přístupů založených na pozemních, bezpilotních a satelitních senzorových platformách pro popis heterogenity porostu jako základního východiska pro cílenou aplikaci přípravků na ochranu rostlin (POR). Metodika je určena pro zemědělskou praxi, zejména pak s tím spo...

Specializovaná mapa (Nmap) „Výskyt kněžice mramorované (Halyomorpha halys) v České republice“ poprvé dokumentuje výskyt tohoto invazního organismu v České republice od roku 2018 až po současnost. Naším záměrem je zaznamenat výskyt tohoto významného škůdce na území ČR.

Specializovaná mapa (Nmap) „Rozšíření vrtule ořechové (Rhagoletis completa) v České republice v letech 2017–2022“ zaznamenává změny ve výskytu invazního škůdce v České republice od roku 2017 až po současnost. Svým obsahem doplňuje a nahrazuje dvě předchozí Nmap „Rozšíření vrtule ořechové v České republice v letech 2017–2020“ a „Rozšíření vrtule oře...

Specializovaná mapa (Nmap) „Výskyt vrtule rakytníkové (Rhagoletis batava) v České republice“ poprvé dokumentuje výskyt tohoto invazního organismu v České republice od roku 2017 až po současnost. Naším záměrem je zaznamenat výskyt tohoto významného škůdce na území ČR.

Obnovení přednáškových cyklů České společnosti entomologické (ČSE) v roce 2018 se setkalo se značným ohlasem nejen posluchačů, ale i potencionálních autorů přednášek. Již na podzim roku 2020 však musel být cyklus, z obecně známých příčin, přerušen. Nekonaly se ani pravidelné Výměnné dny ČSE. Na začátku roku 2021 bylo zjevné, že ani jarní Výměnný de...

From 2014 to 2022, we investigated the length of hibernation in a population of the invasive ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Central Europe. Adults were collected during the autumn immigration to overwintering sites and placed in an artificial hibernaculum held in an unheated closed shelter. The following spring,...

The northern yellow sac spider Cheiracanthium mildei L. Koch, is expanding its range to Central Europe, especially to synanthropic habitats. The spiders become unwanted companions because of the unreasonable fear – arachnophobia, and estetic reason – silk retreats in corners, capturing dust. The most commonly used substances against spiders are pes...

Parasitoids, as important natural enemies, occur in high numbers and help maintain balance in natural ecosystems. Their fitness is traditionally studied as fertility based on the number of offspring in the F1 generation. Here, using gregarious parasitoids as models, we show that this traditional approach omits one important parameter: the clutch si...

The immature stages of the following five Palaearctic Gymnetron species are described for the first time: G. tibiellum Desbrochers des Loges, 1900, G. veronicae (Germar, 1821), G. rotundicolle Gyllenhal, 1838, G. melanarium (Germar, 1821), and G. villosulum Gyllenhal, 1838. These species belong to four different groups previously established accord...

Trehala manna is the edible and trehalose-rich cocoons of a few Larinus species (Coleoptera: Curculionidae: Lixinae: Lixini), and manufactured by the feeding activity of larvae on the Echinops plants. Knowledge on the morphological and molecular properties of immature stages of Larinus species, especially trehala-constructing ones, is still very li...

Carabids are important biological control agents of weeds and other pests in agricultural fields. The carabid community is built upon direct and indirect ecological effects of landscape complexity, field management intensity and biotic components that in interaction make any prediction of community size and composition challenging. We analyse a lar...

The capability of a non-native species to withstand adverse weather is indicative of its establishment in a novel area. An unusually cold winter of 2016/2017 that occurred in the West Carpathians of Slovakia and other regions within Europe provided an opportunity to indirectly assess survival of the invasive ambrosia beetle Xylosandrus germanus (Co...

Metodika shrnuje především nové výsledky a zkušenosti autorského kolektivu, který dlouhodobě studuje biologii některých škůdců obilnin a jejich přirozených nepřátel. Cílem je seznámit čtenáře s nově získanými výsledky, dosud v populární literatuře nepřístupnými (poslední metodická příručka vyšla v roce 2017). Metodika má upozornit na vybrané druhy...

Specializovaná mapa (Nmap) „Rozšíření vrtule ořechové v České republice v roce 2021“ dokumentuje změny ve výskytu invazního škůdce v České republice od roku 2017 až po současnost. Svým obsahem doplňuje a nahrazuje Nmap „Rozšíření vrtule ořechové v České republice v letech 2017–2020“. Hlavním našim cílem je monitorovat změny výskytu v roce 2021, kdy...

Specializovaná mapa (Nmap) „Výskyt zavíječe zimostrázového (Cydalima perspectalis) v České republice“ poprvé dokumentuje výskyt tohoto invazního organismu v České republice od roku 2011 až po současnost. Naším záměrem je zaznamenat výskyt tohoto významného škůdce na území ČR.

We evaluated the differences in frequency (percentage of sampling sessions where the species was recorded) and abundance (mean number of individuals per 100 sweeps) of native species of ladybirds (Coleoptera: Coccinellidae) in the center of Prague, Central Europe, and in its outskirts. Between 2016 and 2019, coccinellids were sampled on Tilia stand...

Wildlife observations submitted by volunteers through citizen science initiatives are increasingly used within research and policy. Ladybirds are popular and charismatic insects, with most species being relatively easy to identify from photographs. Therefore, they are considered an appropriate taxonomic group for engaging people through citizen sci...

Herbivorous insects can escape the strong pressure of parasitoids by switching to feeding on new host plants. Parasitoids can adapt to this change but at the cost of changing their preferences and performance. For gregarious parasitoids, fitness changes are not always observable in the F1 generation but only in the F2 generation. Here, with the mod...

In 2016–2019, seasonal changes in the abundance of the harlequin ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) were established in the city center of Prague, Central Europe, and in its outskirts. Adults were sampled from lime trees ( Tilia spp.) at regular intervals throughout the growing season. The abundance of H. axyridis paral...

Boj proti plevelům představuje jeden z ekonomicky nejnáročnějších aspektů rostlinné produkce. Plevele nejvíce snižují potenciální výnos, a to v průměru až o 10 %. Ke snižování výnosů plevely dochází především následkem konkurence plevelů s plodinou o prostor, živiny, světlo a další faktory potřebné k růstu. Kromě snížení výnosu také plevele znehodn...

Ve zdravé zemědělské krajině nenacházíme jen pěstovanou plodinu a její škůdce, ale mnohem více organismů. Zdravou krajinou myslíme prostředí, které obsahuje minimum reziduí pesticidů, neobsahuje nadbytek průmyslových hnojiv, její půda je zdravá, plná humusu a bohatá na půdní život. Zdravá krajina má bohatou diverzitu i nad povrchem země. Nachází se...

Mature larvae and pupae of Lachnaeus crinitus Schoenherr, 1826 and Rhinocyllus alpinus Gültekin, Diotti and Caldara, 2019 and pupae of R. conicus Frölich, 1792, belonging to the Lixini (Curculionidae: Lixinae), are morphologically described for the first time. They possess all the characters considered distinctive in the immature stages of this tri...

The alfalfa weevil Hypera postica, native to the Western Palearctic, is an invasive legume pest with two divergent mitochondrial clades in its invading regions, the Western clade and the Eastern/Egyptian clade. However, knowledge regarding the native populations is limited. The Western clade is infected with the endosymbiotic bacteria Wolbachia tha...

The intrinsic rate of increase, denoted as r or rm, describes the rate of population growth. Simplified formulas for estimating r have been developed to reduce labour and avoid complicated computations. The aim of this paper was to demonstrate and quantify the systematic bias in estimates of the intrinsic rate of increase provided by the simplified...

To ascertain the direct effects of water stress upon wheat plants (Triticum aestivum L.) and how these effects, in turn, influence the population growth of the bird cherry-oat aphid (Rhopalosiphum padi L.), we conducted a physiological analysis of wheat seedlings grown under three different watering regimes and subsequently determined the populatio...

The gregarious parasitoid strategy allows multiple larvae to complete development in a single host due to their tolerance and/or lower mobility and thus flexibly adjust their reproductive potential amidst changing environmental conditions. Reproductive success is generally measured as the number of each mothers offspring. We propose that with scarc...

Drought represents one of the most severe constraints to agricultural production; therefore, resistance to drought has the highest priority in the development of new cultivars. How insect pests respond to drought-resistant cultivars is poorly under-stood. In this study, by using the rose-grain aphid, Metopolophium dirhodum (Walker), in controlled l...

Téma invazních druhů živočichů je aktuální a živé a diskutují o něm nejen vědci ale už i laická veřejnost. Na webu www.najdije.cz vyzýváme všechny aktivní lidi se zájmem o přírodu a vědu, aby se zapojili do sběru dat přímo v terénu. V místě jejich bydliště, případně všude, kde se pohybují, mohou některý z invazních druhů zaznamenat a po-té jednoduš...

The population density of animals is generally measured as the number of individuals. Here, by using gregarious parasitoids as models, we show that this traditional approach omits one important parameter: the clutch size - body size - fertility correlation. Using this correlation, female gregarious parasitoids deliberately adjust the number of offs...

Both theoretical and empirical work suggests that offspring sex ratio has important consequences on fitness. Within insects, gregarious parasitoids with haplodiploid sex determination represent an ideal model for studying the decision-making process behind the assignment of offspring sex. To gain insight into the offspring sex ratio of gregarious p...

Hmyz poskytuje člověku nenahraditelné přirozené služby, například opyluje zemědělské plodiny, přirozeně přispívá k regulaci škůdců či plevelů, podílí se na rozkládání mrtvé organické hmoty a koloběhu živin v ekosystémech, tvoří potravu např. pro ptáky. V posledních letech přibývá vědecky podložených důkazů o úbytku hmyzu, je tedy nezbytně nutné se...

Cílem této publikace je přiblížit zemědělské praxi povahu a význam ekosystémových služeb, jež jsou poskytovány zemědělství biodiverzitou zemědělské krajiny se zvláštním zřetelem na opylování a regulaci škodlivých činitelů (predace a parazitoidismus škůdců a regulace plevelů). Tyto služby jsou v praxi intenzivního konvenčního zemědělství nedoceněny...

Specializovaná mapa (Nmap) „Rozšíření vrtule ořechové v České republice v letech 2017-2020“ poprvé dokumentuje výskyt tohoto škodlivého organismu v České republice od roku 2017 až po současnost. Naším záměrem je zaznamenat výskyt a rychlost šíření vrtule ořechové na území ČR. Vrtule ořechová (Rhagoletis completa) je invazní dvoukřídlí hmyz z čeled...

Data on plant herbivore damage as well as on herbivore performance have been previously used to identify key plant traits driving plant-herbivore interactions. The extent to which the two approaches lead to similar conclusions remains to be explored. We determined the effect of a free-living leaf-chewing generalist caterpillar, Spodoptera littorali...

Many plant species protect themselves against herbivores through mechanical or chemical so‐called inducible defences (ID). These are regulated via a hormonal cascade which may be under epigenetic control and in which jasmonic acid (JA) plays a prominent role. In this study, we indirectly tested the role of DNA methylation in the production of ID an...

The paper summarizes data concerning biology, ecology, monitoring, and protection against the sugar beet weevil (Asproparthenis punctiventris) which has recently increased in abundance. In Poland, Austria, Hungary and some Eastern European countries, it is in a stage of gradation and causes economically significant damage. The reason for the increa...

Carabids are generalist predators that contribute to the agricultural ecosystem service of seedbank regulation via weed seed predation. To facilitate adoption of this ecosystem services by farmers, knowledge of weed seed predation and the resilience of seedbank regulation with co-varying availability of alternative prey is crucial. Using assessment...

Understanding of habitat favourability has wide relevance to the invasion biology of alien species. We studied the seasonal dynamics of the alien ladybird Harmonia axyridis (Coleoptera: Coccinellidae) in monoculture Scots pine forest stands in southwest Slovakia, Central Europe, from April 2013 to March 2015. Adult H. axyridis were collected monthl...

The mature larva of Cionus olivieri Rosenschoeld, 1838 is described and illustrated in detail for the first time. It is compared with those known from the same genus and other genera in the tribe Cionini and with those of the hypothesized sister tribe Mecinini in the Curculioninae. The larvae of Cionus have three distinctive diagnostic features: th...

Yield losses caused by pests, including aphids, can be substantial in cereals. Breeding for resistance against aphids is therefore desirable for enhancing the economic and environmental sustainability of cereal production. The aim of our study was to reveal the degree of antibiosis against Metopolophium dirhodum (Walker) (Homoptera: Aphididae), in...

The box tree moth Cydalima perspectalis (Walker, 1859) (Lepidoptera: Crambidae) is an invasive species in Europe and a serious pest of box trees (Buxus spp.). In Slovakia, Central Europe, it was first reported in 2012 within the low elevation region with a warm climate. We hypothesize that the cold mountain region of Slovakia would provide less sui...

An invasive alfalfa pest, the alfalfa weevil, has two divergent mitochondrial clades, one of which is infected with Wolbachia that causes unidirectional cytoplasmic incompatibility (CI) in host weevils. The CI is known to be imperfect in interclade hybrids in this weevil. The genetic diversity and geographic distribution of the weevil has not been...

The immature stages of ten Mecinus species are described for the first time and those of two other species are redescribed, adding important chaetotaxy characters that were missing from previous descriptions. These species belong to six of the nine assemblages of Mecinus species previously established according to a phylogenetic analysis. All these...

The Harlequin ladybird Harmonia axyridis Pallas, native to eastern Asia, is an invasive, non-native species that has recently achieved an almost worldwide distribution. A conspicuous feature of this species is colour polymorphism of the elytra. In its native area, the populations consist of a recessive non-melanic morph, several dominant melanic mo...

A new genus and species of the subfamily Cossoninae, Omanocossonus sabulosus gen. et sp. nov. is described from Oman. All specimens including larvae were found on sand dunes on the seashore in roots of Calotropis procera (Aiton) W.T. Aiton. The crucial features, including male and female terminalia, are illustrated, and the taxonomic position of th...

The parasitic wasp Anaphes flavipes (Förster, 1841) (Hymenoptera: Mymaridae) is an important egg parasitoid of cereal leaf beetles. Some species of cereal leaf beetle co-occur in the same localities, but the host specificity of the wasp to these crop pests has not yet been examined in detail. A lack of knowledge of host specificity can have a negat...

The Colorado potato beetle ranks as one of the most important potato pests, mainly due to its high feeding rate during all developmental stages, particularly third and fourth larval instar, and high fecundity. The effect of essential oil (EO) from anise (Pimpinella anisum L. [Apiales: Apiaceae]) prepared as conventional and encapsulated (EN) formul...

Extended abstract: Recording of ladybirds by volunteers has a long history in a number of countries in Europe and other continents (Losey et al., 2007; Brown et al., 2008; Saethre et al., 2010; Gardiner et al., 2012; Grez and Zaviezo, 2015; Pocock et al., 2015; Roy and Brown, 2015; Roy et al., 2015). However, there are inherent spatial, temporal an...

The parasitoid Anaphes flavipes (Foerster) (Hymenoptera: Mymaridae) is a gregarious egg parasitoid which is widely used in biological control against important crop pest beetles of the genus Oulema (Coleoptera: Chrysomelidae). Here, we present the first experimental examination of the influence of adult feeding and timing of host exposure on the lo...

Two new genera, Barclayanthus Borovec & Skuhrovec, gen. nov. and Janakius Borovec & Skuhrovec, gen. nov., assigned to the tribe Trachyphloeini Lacordaire, 1863, are described for three South African species of weevil: Barclayanthus micros Borovec & Skuhrovec, sp. nov., B. cooteri Borovec & Skuhrovec, sp. nov. and Janakius sylvaticus Borovec & Skuhr...

Mature larvae and pupae of Cleonis pigra (Scopoli, 1763) (Curculionidae: Lixinae: Cleonini) are morphologically described in detail for the first time and compared with known larvae and pupae of other Cleonini species. The results of measurements and characteristics most typical for larvae and pupae of Cleonini are newly extracted and critically di...

1. Although studies on plant–herbivore interactions comparing different plant species are common, little is known about the importance of environmental conditions in determining variation in herbivory within single plant species. 2. This study assessed the effects of experimentally manipulated nutrient and water availability on plant palatability,...

Aim Landscape simplification and the spread of invasive species are considered beyond the main threats to global biodiversity. It is well recognized that non‐crop habitats bring complexity to farmland and provide refuge for a wide range of organisms, including arthropods. However, knowledge about the effects of invasive trees on arthropods in non‐c...

The generally known “adult size‐fitness hypothesis” (ASFH) is applied to the gregarious parasitic wasp Anaphes flavipes (Foerster, 1841) (Hymenoptera: Mymaridae). ASFH is dependent on the reproductive strategy of the mother, which means the larger females have more offspring compared to smaller females. Two main factors, the mother's body size and...

The number of parasitoids developed per host is one of the major factors that influences future adult body size and reproductive success. Here, we examined four external factors (host species, heritability, host population density, and presence of predators) that can affect the number of the gregarious parasitoid Anaphes flavipes (Förster, 1841) (H...

To determine the causes of the variation in the seasonal dynamics of Harmonia axyridis (Pallas) in Central Europe, numbers of adults and larvae of this invasive species were recorded on trees (Acer, Betula, Tilia) throughout the growing seasons from 2011 to 2016. Each year beetles were collected every two weeks, using a standardized sweeping method...

The genus Pentatrachyphloeus Voss, 1974, with two known species, is redefined and compared with related genera. An additional thirty seven new species are described here: P. andersoni sp. nov. (South Africa, Mpumalanga); P. baumi sp. nov. (South Africa, Gauteng); P. brevithorax sp. nov. (South Africa, KwaZulu-Natal); P. bufo sp. nov. (South Africa,...

The larva and the pupa of the Palaearctic weevil species Tychius subsulcatus Tournier, 1847 are described and illustrated for the first time. The characters of larva and pupa of T. subsulcatus completely fit the described differential diagnosis of the subtribe Tychiina, genus Tychius, and also Tychius intrusus group. Astragalus onobrychis Linnaeus...

Harmonia axyridis (Pallas), an invasive non-native species in central Europe, can outcompete other aphidophagous species. The distribution and abundance of H. axyridis vary depending on different host plants, and its effects on native coccinellid communities may change accordingly. The distribution and abundance of coccinellids in central Europe (5...