Jiří Nermuť

Biology Centre CAS · Institute of Entomology

Many species of slugs are considered serious pests in agriculture and horticulture around the world. In Europe, slugs of the genera Arion and Deroceras are the most harmful pests in agriculture. Therefore, the main goal of this study was to evaluate the effect of the whole-cell metabolites of 10 strains of five Xenorhabdus and three slug-parasitic...

Entomopathogenic nematodes and entomopathogenic fungi are soil organisms that cause epizootics in insect pests and are therefore important agents in pest management and biocontrol. Many studies focus on the effectiveness of either entomopathogenic nematodes or fungi for controlling pests, though it has been shown that a combination of the two entom...

Nematodes of the genus Phasmarhabditis are facultative parasites of molluscs with a world-wide distribution but, so far, only one species P. hermaphrodita has been thoroughly studied and developed as a biocontrol agent. Therefore, in the present study, we studied the ecology and biocontrol potential of three species (P. bohemica, P. bonaquaense and...

In the present study, we studied ecology of three species of mollusc-parasitic nematodes: Phasmarhabditis bohemica, P. bonaquaense and P. apuliae. We demonstrate that these facultative parasitic nematodes can grow in polyxenic and monoxenic combinations with bacteria Acinetobacter sp., Flavobacterium sp. and Pseudomonas sp. but some combinations do...

An insecticidal and acaricidal additive for a plant substrate. The essence of the technical solution is that the additive consists of a mixture of at least one strain of the entomopathogenic fungus of the genus Isaria (synonym Paecilomyces) at a concentration ranging from 10E5 to 10E7 infectious particles per 1 ml of carrier substrate and at least...

Molluscs, in Europe mainly slugs, are serious pests of many crops and ornamentals. The most harmful species are members of Deroceras and Arion genera. Currently, there are two ways of their control: chemical and biological. Conventional baiting pellets are based on methiocarb (banned in EU), metaldehyde (banned or will be banned soon in most of EU...

Entomopathogenic nematodes are almost ubiquitous soil dwelling organisms that play an important role in natural management of insect populations. Nematodes, especially plant-parasitic, are known to be able to spread and transmit plant-pathogenic viruses and fungi. Isaria fumosorosea (syn. Paecilomyces fumosoroseus) strain CCM 8367 was shown to be v...

Jak už jsme předestřeli na samém konci předchozího dílu, vrátíme se dnes na starý kontinent a budeme se zabývat entomopatogenními hlísticemi z čeledí Steinernematidae a Heterorhabditidae, kterým souhrnně česky říkáme hlístovky. Vůbec první hlístovku pro lidstvo objevil a popsal již v roce 1929 Dr. Gotthold Steiner. Byla to tehdy Neoaplectana carpoc...

Hmyz je napadán stovkami druhů parazitických hlístic, které patří do nejméně 24 různých čeledí. Druhů, které jsou schopné sterilizovat nebo zabít svého hostitele je však o poznání méně a těch které se díky těmto svým schopnostem dostali až do učebnic a praxe ochrany rostlin je poskrovnu. Právě o některých z nich bude náš třídílný seriál. Hned v prv...

Bulb crops are attacked by various soil-dwelling pests and pathogens. Entomopathogenic (EPFs) and mycoparasitic fungi (MPFs) which are distributed in natural and agricultural soils worldwide can play an important role as natural enemies of bulb pests. The species richness and density of these fungi in onion and garlic fields have not been investiga...

Colorado potato beetle Leptinotarsa decemlineata is among the most destructive pests of potatoes quickly developing resistance to traditional insecticides. In the present study, we tested the effect of various species and strains of entomopathogenic nematodes on CPB adults, and subsequently, the most effective nematodes were applied alone and in co...

The bulb mite, Rhizoglyphus robini, is a serious pest of garlic, onion and other crops. The mite is usually found in association with dangerous fungal pathogens such as Fusarium spp. Control of this pest has relied upon the use of synthetic acaricides but chemical control of the bulb mite is difficult because it is able to develop resistance quickl...

Roztoči rodu Rhizoglyphus, tedy kořenohubové, jsou celosvětově rozšíření škůdci cibule, česneku a mnoha okrasných a jiných rostlin, proti kterým prakticky neexistují dostupné metody cílené biologické ochrany. Jedním z cílů naší studie v plném rozsahu publikované v časopise Biological Control bylo zhodnotit, jaký vliv mají aplikace entomopatogenních...

Entomopatogenní hlístice čeledí Steienernematidae a Heterorhabditidae, stejně jako entomopatogenní houby řádu Hypocreales, jsou široce rozšířené půdní organismy, běžně užívané jako bioagens v ochraně rostlin. Nejedna studie již ukázala, že kombinace různých bioagens může vést ke zvýšení účinnosti proti cílovým organismům. V naší studii jsme se s oh...

The entomopathogenic nematode Steinernema siamkayai has been a subject of several detailed studies but its morphological, molecular and ecological characterisation is still incomplete. In the present study we studied morphology of several strains of S. siamkayai using morphometrics and light and scanning electron microscopy (SEM) and we aimed to co...

Entomopathogenic nematodes and fungi are globally distributed soil organisms that are frequently used as bioagents in biological control and integrated pest management. Many studies have demonstrated that the combination of biocontrol agents can increase their efficacy against target hosts. In our study, we focused on another potential benefit of t...

Biological control (biocontrol) as a component of pest management strategies reduces reliance on synthetic chemicals, and seemingly offers a natural approach that minimizes environmental impact. However, introducing a new organism to new environments as a classical biocontrol agent can have broad and unanticipated biodiversity effects and conservat...

A new species of entomopathogenic nematode, Steinernema riojaense n. sp., was isolated during a survey in La Rioja province of Spain. Morphological and morphometric traits place the new species in the glaseri -group, which is characterised by having the largest infective juvenile (IJ) with an average body length in excess of 1000 μ m. The IJ of S....

The bulb mite, Rhizoglyphus robini, is serious pest of garlic, onion and many other crops. Control of this pest has relied upon the use of synthetic acaricides and insecticides, but this option is now limited mainly due to withdrawal of some chemical pesticides. Thus, alternative control methods, e. g. biological control, need to be developed and i...

Alloionema appendiculatum Schneider, 1859 (Rhabditida: Alloionematidae) is a common parasite of terrestrial molluscs capable of causing high snail mortality in heliculture. It has also been described as a parasite of the invasive slug Arion vulgaris Moquin-Tandon, 1855 (Pulmonata: Arionidae), a serious pest in central Europe. Nontheless, our knowle...

The lateral field pattern of infective juveniles of the nematode family Steinernematidae is an important taxonomic character. Scanning electron microscopy (SEM) shows the number of ridges and lines or incisures clearly, but does not provide other details. In the present study, ten species from six clades of Steinernematidae have been studied for th...

Nematodes form various associations with terrestrial gastropods including obligatory parasitic, paratenic, phoretic or necromenic mode. There are over 80 gastropod parasitic nematode species from twelve families (Agfidae, Alaninematidae, Alloionematidae, Angiostomatidae, Araeolaimidae, Ascarididae, Cephalobidae, Cosmocercidae, Diplogasteridae, Merm...

Actually (March 2019) there are eleven described species belonging to the genus Phasmarhabditis. All of them are worldwide distributed soil-dwelling, facultative parasites of slug and snails that parasitize many mollusc families e.g. Limacidae, Agriolimacidae, Arionidae, Milacidae, Vaginulidae, Helicidae etc. But the only species that has been deve...

Recent studies revealed that facultative insect parasitic nematodes of the genus Oscheius often co-invade insect cadavers together with entomopathogenic nematodes. This raised a question whether these nematodes could negatively affect EPN populations especially in agroecosystems, where the EPN populations are less abundant. Studies focused on the c...

Gastropods comprise nearly 60,000 species of aquatic as well as terrestrial mollusks, primarily snails and slugs. The giant African land snail (Achatina fulica) is one of the most popular pet snails worldwide. This gastropod mollusk is known as the intermediate host of several parasites that cause severe diseases in pets, free-ranging vertebrates,...

Bulb mites of the genus Rhizoglyphus are cosmopolitan pests of onion, garlic and ornamental plants. Despite the growing awareness against the use of pesticides, growers continue to use insecticides as the main control method. Thus, the search for environmentally safe alternative control methods, such as effective biocontrol agents, is of paramount...

Terrestrial gastropod molluscs are widely distributed and are well known as pests of many types of plants that are notoriously difficult to control. Many species of nematodes are able to parasitize land snails and slugs, but few of them are lethal to their host. Species and/or populations of mollusc-parasitic nematodes (MPNs) that kill their hosts...

The mucron in male steinernematid nematodes may be missing or present either in the first or second generation, or missing in both generations, with variable shape. However, for many species, the information on mucron morphology is incomplete and its taxonomic significance and distribution remain unclear. The present study assessed mucron morpholog...

In the present study the screening of entomopathogenic nematodes in the fields of onion and garlic specialized farms in the Czech Republic and Israel was performed and more than thirty strains of Steinernema and Heterorhabditis nematodes were isolated. Selected strains were tested for infectivity and pathogenicity against garlic and onion pest mite...

The genus Alloionema (Rhabditida: Alloionematidae) currently includes three nominal species-the type species, Al-loionema appendiculatum, and two recently described species: A. similis and A. californicum. Comparison of morpholog-ical, molecular and ecological characters demonstrates that A. similis and A. californicum belong to the same species, p...

Ptilodactyla crenatostriata Redtenbacher, 1868 (Coleoptera: Byrrhoidea: Ptilodactylidae) described from Rio de Janeiro, Brazil, is transferred to the genus Phytocerum Costa, Vanin, Lawrence & Ide, 2003 (Coleoptera: Elateroidea: Cerophytidae). Based on the examination of the holotype, deposited in the Naturhistorisches Museum Wien, Austria, Phytocer...

This book contains chapters that capture the full breadth of the basic and applied information on entomopathogenic (EPNs) and slug parasitic nematodes (SPNs) that are used or have potential in the management of insect pests, molluscs and/or other researched targets such as plant parasitic nematodes. The information includes the remarkable developme...

During a survey of the biodiversity of entomopathogenic nematodes in Ukraine, a population of Steinernema arenarium, strainCh, was recovered in the sensitive Chornobyl Exclusion Zone. In the present work, this strain was morphologically and mole-cularly characterised using light microscopy and the sequences of the ITS and D2-D3 region of the 28S rD...

A new species of entomopathogenic nematode, Steinernema pwaniensis n. sp., belonging to the glaseri group, is described from Tanzania. The infective juveniles of S. pwaniensis n. sp. are characterized by a body length of 978 mm (808–1131), distance from anterior end to excretory pore of 86 mm (80–95) and a tail length of 87 mm (75–95). The ratios a...

Phasmarhabditis bohemica n. sp. is described and illustrated from the body of Deroceras reticulatum from the village of Chelčice, the Czech Republic. Morphological and molecular data showed that the new isolate is close to other species of Phasmarhabditis, particularly P. californica and P. papillosa. Females are characterised by a body length of 2...

As the mollusc pests cause more and more damages in agriculture and horticulture parasites of molluscs are getting much attention. Phasmarhabditis nematodes as one of the most common slug and snail parasites do not fall behind. Phasmarhabditis hermaphrodita is the best known mollusc-parasitic nematode of the family Rhabditidae (Nematoda). However d...

Bulb mites of the genus Rhizoglyphus are among the most serious pests of garlic and onion but also tulips, hyacinths and other plants. Females of these soil dwelling mites lay their eggs into the underground parts of many plants and their larvae altogether with the adult stages cause damage to plant tissues that are, consequently, more sensitive to...

A new species of the family Alloionematidae was isolated from a rotten winged gourd at White Crane Garden, San Francisco, USA, sampled by Christopher Nelson in November 2010, and a live culture is deposited in Félix Lab Strain Database (http://www.justbio.com/worms/index.php), IBENS, Paris, France. Specimens from the culture have been examined. Bot...

Phasmarhabditis bonaquaense n. sp. is described and illustrated from the body of Malacolimax tenellus, from the locality of České Švýcary near the village of Dobrá Voda, the Czech Republic. Females are characterized by a body length of 2349 (1878-2626) μm and a cupola shaped tail with a long hyaline hair-like tail tip. Extremely prominent papilla-l...

A new nematode species belonging to the family Rhabditidae, genus Phasmarhabditis, was isolated in the city of Bari (strain BAR) and near the village Gravina (strain GRA) in Apulia, Italy, and is described herein as Phasmarhabditis apuliae n. sp. The original hosts were Milax sowerbyi and M. gagates. Females are 2623 (2262-2848) μm long with a long...

A new species of entomopathogenic nematode (EPN), Steinernema biddulphi n. sp., was isolated from a maize field in Senekal, Free State Province of South Africa. Morphological and molecular studies indicated the distinctness of S. biddulphi n. sp. from other Steinernema species. Steinernema biddulphi n. sp. is characterized IJs with average body len...

Entomopathogenic and molluscoparasitic nematodes are important parasites of many insects and molluscs, respectively. Due to their infectivity, the possibility of mass production by industrial techniques and the relative safety to nontarget organisms and environment, these organisms represent an attractive agent for biological control of many pests....

A new nematode species belonging to the family Alloionematidae was originally isolated by Dr Marie Anne Félixon 16 December 2007 from a rotting coconut at the boat boarding point in Estuary island resort, Poovar, Kerala, India. Both morphologically and molecularly, the new isolate resembles Neoalloionema tricaudatum but, unlike N. tricaudatum this...

Steinernema beitlechemi n. sp. is a new species of entomopathogenic nematode isolated from soil samples collected in Bethlehem, Free State province, South Africa. The infective juveniles of S. beitlechemi n. sp. are characterised by a body length of 696 (606-768) μm, position of nerve ring of 96 (86-105) μm from the head and lateral fields with six...

Parazitické hlístice, které využívají měkkýše jako mezihostitele, paratenické nebo definitivní hostitele, tvoří skupinu více než stovky druhů. Další nové druhy jsou neustále popisovány, avšak jejich ekologie zůstává povětšinou zcela neznámá a nepovšimnutá. Pouze několik málo druhů bylo prozkoumáno blíže. Právě o nich a o tom kdy a jak vznikl jejich...

Several taxonomic studies of the entomopathogenic nematode family Steinernematidae have reported on the minute tail projections on the tail tips of females of the first generation; however, the occurrence and morphology of these traits in other steinernematid species and their taxonomic significance are still unclear. In the present study, the tail...

A nematode from the genus Steinernema was isolated in Zulia state (North-western, Venezuela). Morphological, morphometric and molecular studies indicated that this nematode belongs to the “bicornutum” group and is described herein as Steinernema goweni n. sp. Steinernema goweni n. sp. is characterised by morphometrics of its infective juveniles, w...

A study of nematodes associated with the large larch bark beetle Ips cembrae (Heer 1836) was carried out at three locations in the Czech Republic. The proportion of beetles infested by endoparasitic nematodes (representatives of genera Contortylenchus, Parasitylenchus, Cryptaphelenchus and Parasitorhabditis) ranged from 29.9 to 50.9%. Significant d...

Surveying the biodiversity of entomopathogenic nematodes in Zulia and Falcón states, north-western Venezuela, two populations of a new Steinernemaspecies were isolated from soil samples. Morphological, morphometric and molecular data indicate that the new species belong to the ‘ bicornutum-group’ of Steinernema. The new species can be separated fro...

Alloionema appendiculatum is a common juvenile parasite of many terrestrial molluscs. Its 3rd stage juveniles (dauers) invade the foot muscle of snails and slugs. Dauer juveniles develop into 4th stage juvenile, which then leave the host. Later they mature and reproduce in the soil. A population of A. appendiculatum was isolated from infected indiv...

The internal transcribed spacers of rDNA are among the most important molecular markers used in the taxonomy and phylogeny of entomopathogenic nematodes. However, their ease of use and the results they provide can be confounded by the presence of intra-individual variability. In the present study we screened 40 strains of S. feltiae and S. kraussei...

In the past 70 years, EPN research in the Czech Republic has contributed to the field with a number of important achievements, especially in the taxonomy of entomopathogenic nematodes (EPNs). Leading persons involved have been insect pathologist Dr. Jaroslav Weiser and his pupil Dr. Zdeněk Mráček. In this short overview, we will focus on the most i...

Ips duplicatus (Sahlberg) is an important forest pest in central Europe, but its nematode associates have seldom been studied. Therefore, nematodes associated with I. duplicatus were determined at three localities in the Czech Republic. The percentage of beetles with phoretic nematodes ranged from 18 to 65%. Micoletzkya buetschlii and other phoreti...

This group of parasitic nematodes consists of approximately 24 families, although obligate parasites can be found in eight of them. Some of these enigmatic nematodes adopted amazing life strategies and serve as bioagents to control populations of mosquitoes or woodwasps. In this article we review the biology, ecology and distribution of these organ...

The effect of different growing substrates on the development of the slug parasite Phasmarhabditis hermaphrodita has been studied in a series of laboratory experiments. Wild, laboratory and Nemaslug strains of P. hermaphrodita and their monoxenic counterparts with Moraxella osloensis (CCM 5605T) were reared on homogenised pig kidney, Deroceras reti...

A new entomopathogenic nematode, Steinernema huense sp. n., belonging to the carpocapsae group, was recovered in Bach Ma National Park (Thua Thien Hue province) Vietnam. Steinernema huense sp. n. infective juveniles are characterised by short body length of 527 (444-571) μm, distance from anterior end to excretory pore of 43 (38-46) μm, anterior en...

A new steinernematid nematode, herein described as Steinernema poinari sp. n., was recovered by baiting soil samples with the last instar wax moth larvae Galleria mellonella in three localities of southwest Bohemia, Czech Republic. Morphological and molecular data confirmed this nematode as a new species which belongs to the affine/intermedium grou...

In the light of current morphological knowledge, the Steinernema carpocapsae morphology is not satisfactorily described, some important characters of this species are missing and no thorough molecular characterisation of this species has been performed. Steinernema carpocapsae represents a type of the 'carpocapsae' group and thus a main objective o...

The effect of intraspecific competition on the development and reproduction of the slug parasitic nematode Phasmarhabditis hermaphrodita was studied in a series of laboratory experiments. Different inocula concentrations (1, 10, 25, 50, 100, 250, 500 and 1000) of P. hermaphrodita dauer juveniles (DJ) were applied to 0.02 g of homogenised slug Deroc...

A new heterorhabditid nematode was recovered in orchards in the Beijing area. Morphological and molecular dataconfirmed this nematode as a new species, which belongs to the bacteriophora-group with sister taxa Heterorhabditisbacteriophora and H. georgiana. The nematode was named H. beicherriana n. sp. and is characterized by males,hermaphrodites, f...

In the present study the response of Phasmarhabditis hermaphrodita to different cues of Deroceras reticulatum was examined on agar plates and in sand filled olfactometers. The entomopathogenic nematode (EPN) Steinernema feltiae and the cues of Galleria mellonella were used as a reference. The movement of P. hermaphrodita in both arenas was more int...

The effect of different substrates on persistence of the facultative slug parasitic nematode Phasmarhabditis hermaphrodita was studied. Four different substrates (sand, leaf compost, organic horticultural substrate and garden soil) were inoculated with P. hermaphrodita strain B1, isolated in central Bohemia, and the persistence of this nematode was...