Susceptibility of selected stored product insects to a combination treatment of pyriproxyfen and novaluron

There are many published studies of either insect growth regulators (IGR) or chitinase inhibitors applied directly to larvae of stored product insects or incorporated into their diets, but few studies evaluating efficacy of IGRs or chitinase inhibitors applied alone or in combination with a surface for residual control. Tests were conducted to evaluate susceptibility of Tribolium castaneum (Herbst), the red flour beetle, Trogoderma variabile (Ballion), the warehouse beetle, and Dermestes maculatus (DeGeer), the hide beetle, to Tekko^® Pro which contained the IGR pyriproxyfen and the chitinase inhibitor novaluron as active ingredients. Efficacy was assessed by adult emergence of exposed immatures, an index based on development of those exposed immatures, and progeny production of exposed adults. Concrete arenas were treated with the label rate of the insecticide applied to a surface, and bioassays were conducted at 0–16 weeks post-treatment. No exposed T. castaneum eggs or larvae reached the adult stage and index values for exposed eggs and larvae remained near the minimum. Adult emergence of T. variable from eggs or larvae did not exceed 25% for the first 8 weeks of the test, but at the end of the test at 16 weeks adult emergence was 44 and 71%, respectively, for eggs and larvae. No eggs or larvae of D. maculatus emerged as adults, but excessive cannibalization in untreated controls occurred throughout the test. Results show that Tekko^® Pro will give residual control of T. castaneum and T. variabile, and could replace older conventional neurotoxic insecticides for management of stored product insects.     

An invasive insect herbivore disrupts plant volatile-mediated tritrophic signalling

Plants respond to insect attack by emission of volatile organic compounds, which recruit natural enemies of the attacking herbivore, constituting an indirect plant defence strategy. In this context, the egg parasitoid Trissolcus basalis is attracted by oviposition-induced plant volatiles emitted by Vicia faba plants as a consequence of feeding and oviposition by the pentatomid host Nezara viridula. However, this local tritrophic web could be affected by the recent invasion by the alien pentatomid bug Halyomorpha halys, an herbivore that shares the same environments as native pentatomid pests. Therefore, we investigated in laboratory conditions the possible impact of H. halys on the plant volatile-mediated signalling in the local tritrophic web V. faba–N. viridula–T. basalis. We found that T. basalis wasps were not attracted by volatiles induced in the plants by feeding and oviposition activities of H. halys, indicating specificity in the wasps’ response. However, the parasitoid attraction towards plant volatiles emitted as a consequence of feeding and oviposition by the associated host was disrupted when host, N. viridula, and non-associated host, H. halys, were concurrently present on the same plant, indicating that invasion by the alien herbivore interferes with established semiochemical webs. These outcomes are discussed in a context of multiple herbivory by evaluating the possible influences of alien insects on local parasitoid foraging behaviour.     

Behavioral responses of predaceous minute pirate bugs to tridecane,a volatile emitted by the brown marmorated stink bug

Since its introduction from Asia, the brown marmorated stink bug, Halyomorpha halys (Stål), has become a pest of many agricultural crops in the USA. Insect predators utilize H. halys as prey; however, the chemical cues used by them in prey location are largely unknown. Here, we hypothesized that tridecane, an H. halys-associated volatile, acts as a kairomone for the predaceous minute pirate bug, Orius insidiosus (Say). We conducted laboratory, greenhouse, and field experiments to: (1) assess the attraction of adult O. insidiosus to H. halys-damaged bean pods and tridecane in cage studies, and its effect on egg predation; (2) video record the behavioral response of O. insidiosus males and females to tridecane in a four-arm olfactometer; and (3) test whether Orius spp. are attracted to tridecane-baited sticky traps in peach, blueberry, and sunflower fields, and its effect on egg predation. In the greenhouse, O. insidiosus was attracted to H. halys-damaged pods and artificial plants baited with tridecane in the presence of prey (sentinel eggs); however, this attraction rarely led to increased egg predation. Although both O. insidiosus males and females spent more time in the arm of the olfactometer with tridecane, males were more responsive at a lower concentration than females. Similarly, Orius spp. were more attracted to tridecane-baited than unbaited traps in the field; however, there was no effect on egg predation. Altogether, while O. insidiosus is attracted to tridecane, this attraction did not always lead to higher predation, suggesting that this kairomone likely acts as an arrestant.     

Diversity of Ophiostomatales species associated with conifer-infesting beetles in the Western Carpathians

Bark beetles (Coleoptera: Curculionidae, Scolytinae) are commonly recognised as important agents of tree mortality in coniferous forests of the Western Carpathians. They, together with weevils, are consistently associated with ophiostomatoid fungi. Information regarding conifer beetle-associated fungi in the Western Carpathians remains incomplete and unreliable, particularly with respect to fir-infesting bark beetles. This study aims to clarify associations between fungi in the genera Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in Norway spruce (Picea abies), European larch (Larix decidua) and silver fir (Abies alba). Samples associated with 20 bark beetle species and weevils were collected from nine stands in Poland and the Czech Republic. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for four gene regions (ITS, LSU, ß-tubulin, TEF 1-α) and phylogenetic analyses. In total, 46 distinct taxa were identified, including 25 known and 21 currently unknown species. Several associations between fungi and subcortical insects were recorded for the first time. In addition, O. borealis and O. quercus were detected from A. alba for the first time. The composition of the fungal communities varied among the studied tree species and to a lesser degree among the beetle species. The spruce-infesting bark beetles were commonly associated with species of Leptographium s. l. and Ophiostoma s. str.; the larch-infesting bark beetles were often associated with Ophiostoma s. str. and Sporothrix, while the fir-infesting bark beetles were commonly associated with Ophiostoma s. str. and Graphilbum. The most commonly encountered fungal associates of the examined insects were (a) Grosmannia cucullata, G. piceiperda, Grosmannia sp. 1, Ophiostoma macroclavatum and O. piceae with the spruce-infesting bark beetles; (b) O. pseudocatenulatum and Sporothrix sp. 1 with the larch-infesting bark beetles; and (c) O. piceae, Ophiostoma sp. 2 and Graphilbum sp. 2 with the fir-infesting bark beetles. The differences in fungal associates among the bark beetle species occurring on P. abies, L. decidua and A. alba could be linked to the different habitats that these beetles occupy.     

The effects of non-host plant extracts on electroantennogram responses,behavior and egg hatching of codling moth, <Emphasis Type="Italic">Cydia pomonella</Emphasis>

The codling moth (Cydia pomonella L.) is a significant pest of pome fruit throughout the world. Behavioral and ovicidal activities of five non-host plant extracts (Arctium lappa, Bifora radians, Humulus lupulus, Verbascum songaricum, Xanthium strumarium), synthetic sex pheromone, (E,E)-8,10-dodecadienol (codlemone), and the plant volatile lure, (2E,4Z)-2,4-decadienoate (pear ester) were evaluated against the codling moth, C. pomonella L. Codlemone elicited the greatest electroantennogram (EAG) response (6.2 ± 1.2 mV) of the compounds tested from male C. pomonella while pear ester elicited 1.7 ± 0.1 mV EAG response in female moths. Codlemone attracted 34.5% of male C. pomonella in olfactometer studies, and it was followed by the X. strumarium extract with 24.8%. There was a significant difference between the behavior of unmated and mated females. V. songaricum extract was the most active extract, attracting 25.4% of unmated females. However, mated C. pomonella females exhibited greatest attraction to pear ester. In a wind tunnel bioassay, combining X. strumarium with codlemone significantly increased the response of male upwind flight and source contact as compared with codlemone alone. All plant extracts, except for V. songaricum, significantly reduced the number of eggs laid. The plant extracts exhibited some toxic effects to eggs, and hatching rate of eggs was reduced as compared with the control. Our results indicate that some of the plant extracts tested are potential candidates for practical use after elucidation and characterization of active compound(s).     

Direct and admixture toxicity of diatomaceous earth and monoterpenoids against the storage pests <Emphasis Type="Italic">Callosobruchus</Emphasis><Emphasis Type="Italic">maculatus</Emphasis> (F.) and <Emphasis Type="Italic">Sitophilus oryzae</Emphasis> (L.)

We investigated the effects of two commercial diatomaceous earth based insecticides (DE), Protect-It^® and SilicoSec^®, the nano-structured silica product AL06, developed by the section for Urban Plant Ecophysiology at Humboldt University Berlin, and the monoterpenoids, eugenol, and cinnamaldehyde on two stored product pests, Callosobruchus maculatus and Sitophilus oryzae. Protect-It^® was more effective than SilicoSec^® against C. maculatus while the reverse was true for S. oryzae. Generally C. maculatus was more sensitive towards DE and silica treatment than S. oryzae. Mortality rate of both pest species increased when DE’s were applied to food commodities previously treated with a monoterpenoid. In admixture experiments, the toxicity of SilicoSec^® + cinnamaldehyde (LD₅₀ = 42.73 ppm), SilicoSec^® + eugenol (LD₅₀ = 24.30 ppm), and Protect-It^® + eugenol (LD₅₀ = 2.60 ppm) was increased over DE alone against S. oryzae. Both substances showed a synergistic effect considering their co-toxicity coefficient relative to the LD₅₀-value. In contrast, we could not find any synergistic effects in experiments with C. maculatus. Here only Protect-It^® + cinnamaldehyde (LD₅₀ = 20.84 ppm) showed an additive effect while all other combinations of monoterpenoid and DE indicated antagonistic effects. In addition to contact insecticidal effects both monoterpenoids showed a strong fumigant action. The presented results indicate that the natural product DE has great potential to replace synthetic pesticides commonly used in stored product pest management. Efficacy of DE can be improved by adding certain monoterpenoids against certain insect pests.     

Foraging wireworms are attracted to root-produced volatile aldehydes

Soil-dwelling insects are known to react to chemical cues they encounter in the rhizosphere. Whether wireworms (Coleoptera, Elateridae) use root-emitted volatile organic chemicals to localize their host plant remains, however, poorly understood. Here, we aimed at identifying chemical cues released by barley roots that attract Agriotes sordidus. In a first behavioral experiment, we assessed the ability of wireworms to orient towards live barley roots, using dual-choice olfactometers suitable for belowground insects. Then, we collected the volatile organic compounds (VOC) produced by barley roots using a dynamic head-space sampling approach. VOC were quantified and identified using gas chromatography—mass spectrometry (GC–MS). The odorant blend is composed of four aldehydes, namely hexanal, (E)-hex-2-enal, (E)-non-2-enal, and (E,Z)-nona-2,6-dienal. In a second set of dual-choice bioassays, wireworms were attracted towards a synthetic blend of these four major compounds. However, the synthetic blend was not as attractive as live roots, which is partially explained by the absence of CO₂, commonly known as a strong attractant for soil-dwelling insects. While CO₂ indicates the presence of living material in the vicinity, we hypothesize that additional VOC inform about the plant suitability. A better understanding of these belowground signals would contribute to the development of new integrated control strategies against wireworms.     

Behavioral responses of the egg parasitoid <Emphasis Type="Italic">Trissolcus japonicus</Emphasis> to volatiles from adults of its stink bug host, <Emphasis Type="Italic">Halyomorpha halys</Emphasis>

Halyomorpha halys, originating from East Asia, has become an important agricultural pest in northern temperate regions since its accidental introduction into North America in the mid-1990s and Europe in 2007. Trissolcus japonicus is the predominant egg parasitoid of this pest in its native range. Here, we tested the hypothesis that T. japonicus uses volatiles associated with H. halys adults during host location. The effects of these volatile compounds on H. halys adults were also assessed. Chemical analysis with GC-MS and electrophysiological analysis with GC-EAD revealed the presence of two bioactive volatile compounds from H. halys adults, n-tridecane and (E)-2-decenal. In the Y-tube assays, female T. japonicus were attracted by n-tridecane but strongly repelled by (E)-2-decenal. Furthermore, host searching time of female T. japonicus was significantly reduced when an H. halys egg mass was treated with n-tridecane and prolonged when treated with (E)-2-decenal or a mixture of (E)-2-decenal and n-tridecane. Male H. halys were significantly attracted by n-tridecane, whereas females had no response to this compound in the Y-tube assays. (E)-2-Decenal strongly repelled male and female H. halys in the Y-tube assays. We discuss the multifunctional kairomonal and other possible roles of these semiochemicals at different trophic levels in the context of intra- and inter-specific chemical communication, in the H. halys–T. japonicus system.     

Occurrence of <Emphasis Type="Italic">Bursaphelenchus mucronatus</Emphasis> (Nematoda; Aphelenchoididae) in France and association with <Emphasis Type="Italic">Monochamus galloprovincialis</Emphasis> (Coleoptera: Cerambycidae)

As a consequence of the recent introduction of the pine wood nematode Bursaphelenchus xylophilus in Portugal, nematodes of the genus Bursaphelenchus were looked for in various French pine forests, in trees attacked by Monochamus galloprovincialis, the vector insect of B. xylophilus, and in the insects themselves. Trap trees were felled in 12 localities distributed all over the country. Nematodes were extracted from transversal stem discs; insects emerging from the trap trees were studied. B. hellenicus, B. leoni, B. mucronatus and B. sexdentati were isolated, but not B. xylophilus. The presence of B. mucronatus and the absence of B. xylophilus were confirmed by molecular markers. B. mucronatus was isolated from several regions with an average prevalence of 19%. The infestation of M. galloprovincialis by B. mucronatus reached 26.7%. The wide distribution of B. mucronatus in France could have an effect on the extension of B. xylophilus in a case of an introduction.     

<Emphasis Type="Italic">Orius laevigatus</Emphasis> strengthens its role as a biological control agent by inducing plant defenses

Orius laevigatus is a generalist predator that is widely used in augmentative strategies against the key pest of sweet pepper, Frankliniella occidentalis. Despite being a zoophytophagous predator, the phytophagous behavior of O. laevigatus has not been previously explored in depth nor has the impact of phytophagy on plant physiology. Here, the hierarchical significance of O. laevigatus feeding on sweet pepper is compared with other behaviors. O. laevigatus spends the majority of its time (38%) feeding on apical meristems and apical fresh leaves, which were also preferred residence locations. Here, the phytophagous feeding behavior of O. laevigatus on sweet pepper is shown to trigger defensive responses in the plant. These O. laevigatus plant-induced defenses are then shown to contribute to the repellence or attraction of pests or natural enemies, respectively. Specifically, O. laevigatus-punctured sweet pepper plants induce repellency for the whitefly Bemisia tabaci and the thrips species F. occidentalis. In contrast, the whitefly parasitoid Encarsia formosa was significantly attracted to O. laevigatus-punctured plants. The plant responses to O. laevigatus punctures include the release of an altered blend of volatiles and activation of the jasmonic acid and salicylic acid signalling pathways. These results highlight an interesting facet to the biology of O. laevigatus, in which the ability of the predator to induce defensive responses in sweet pepper plants may serve to improve the biological control of both thrips and whiteflies.     

Pentatomid host suitability and the discovery of introduced populations of <Emphasis Type="Italic">Trissolcus japonicus</Emphasis> in Oregon

Trissolcus japonicus is an egg parasitoid of Halyomorpha halys, brown marmorated stink bug, a severe agricultural pest in the USA. T. japonicus is being evaluated in quarantine as a classical biological control agent to manage H. halys populations in the USA. To determine T. japonicus’ potential for successful management of the pest, we performed a series of no-choice and paired-host-range tests, evaluating parasitism and host recognition in ten nontarget insects. In laboratory no-choice tests, T. japonicus successfully parasitized egg masses of seven Pentatomidae native to Oregon in addition to H. halys. Mean parasitism proportions of egg masses were greater than 40% in two species, B. dimidiata and H. abbreviatus, and were statistically similar to parasitism of H. halys. However, paired-host tests identified higher proportions of parasitized H. halys egg masses compared to four other pentatomids. T. japonicus was equally attracted to volatiles produced by H. halys and other pentatomids but demonstrated significantly longer arrestment response time on surfaces with H. halys contact kairomones. Although host acceptance patterns were similar between stink bug species, our results suggest a greater potential for parasitoid development in H. halys eggs compared to the native pentatomids. During host-range testing, we detected field populations of T. japonicus at 11 sites in Portland, OR, indicating an unintentional introduction and establishment. Further work is needed to characterize its nontarget activity and dispersal patterns in areas where H. halys causes economic damage in Oregon.     

Electrophysiological responses of <Emphasis Type="Italic">Thaumetopoea pityocampa</Emphasis> females to host volatiles: implications for host selection of active and inactive terpenes

Volatiles from newly cut branches with needles of Pinus sylvestris L. were collected with headspace sampling technique, and then identified and quantified by combined gas chromatographic-mass spectrometry (GC-MS). The response of antennae of the female pine processionary moth, Thaumetopoea pityocampa, to these volatiles was recorded by coupled gas chromatographic-electroantennographic detection (GC-EAD). Surprisingly, the most common and major monoterpene hydrocarbons (MT), α-pinene, 3-carene, and β-pinene were antennally inactive. Female antennae responded strongly only to four minor MT components, myrcene, β-phellandrene, trans-β-ocimene, and terpinolene. Weaker, but repeatable responses were also found to limonene, cis-β-ocimene, and γ-terpinene. Further EAD recordings with two synthetic MT mixtures supported our findings from the natural material. When separating the two enantiomers of limonene by running different synthetic MT mixtures, the EAD response was found only to the(?)-enantiomer, but not to the opposite (+)-enantiomer. EAD-responses were also found to some less volatile compounds, such as sesquiterpenes (SqT), active at ng-levels. The sensitivity and specificity of the antenna to a select number of active host MTs and SqTs suggest that these play a role in the host selection process of T. pityocampa females.     

Occurrence of pathogens in associated living bark beetles (Col., Scolytidae) from different spruce stands in Austria

Pathogen occurrence was studied in 16?099 adult specimens of 10 different bark beetle species, which live associated on Norway spruce (Picea abies (L.) Karst.). Beetles (mainly Ips typographus L. and Pityogenes chalcographus L.) were collected from 6 different localities in Austria (4 secondary spruce stands and 2 natural forest type stands, 9 sampling plots in total) in elevations between 400?m and 1600?m. Various viral, protozoan, and fungal pathogens could be diagnosed with a light microscope in the examined beetles. Numerous pathogen species were known from former studies, some pathogens were totally new or could be found in a new host species beside their type host. The most dominant pathogen species were Protozoa, Gregarina cf. typographi, Malamoeba cf. scolyti, and Chytridiopsis cf. typographi. Over the whole investigation period, the highest pathogen diversity with eight pathogen species was found in I. typographus. Differences were observed in the pathogen complex of each beetle species from the different collection sites and in different years of investigation. Several species showed an overlapping in their host range and infected various bark beetle species. Furthermore, pathogen occurrence and prevalence differed in bark beetles from 4 different sampling plots in an area (one locality) within a distance of a few kilometres.     

Studies on diets and population dynamics of the cigarette beetle <Emphasis Type="Italic">Lasioderma serricorne</Emphasis> F. (Col., Anobiidae)

Aromatic spice crops such as coriander, Coriandrum sativum L., and fennel, Foeniculum vulgare L., are among the major seeds exported to the international market. Observations on the stores of these crops revealed differences in their susceptibility to the cigarette beetle, Lasioderma serricorne (F.) (Col., Anobiidae). Coriander seeds proved to be the most appropriate diet for the beetle. The population dynamics of L. serricorne (F.) was determined, showing 3 generations during the period from May to October.     

Identification of pests and assessment of their damage on <Emphasis Type="Italic">Carapa procera</Emphasis> and <Emphasis Type="Italic">Lophira lanceolata</Emphasis> in Burkina Faso,West Africa

Nontimber forest products are a source of income for women in rural African communities. However, these products are frequently damaged by insect pests. The present study investigates the diversity and damage rates of insect pests that attack Carapa procera seeds and Lophira lanceolata fruits. The experiment was set up in western Burkina Faso and, for C. carapa, consisted of pests collected from seeds that had fallen to the ground and from stockpiled seeds. For L. lanceolata, pests were collected from fruits on the trees, and on the ground. The collected samples were sent to the laboratory to estimate the proportion of damaged seeds/fruits and rear the insects. The results showed that Ephestia spp., Tribolium castaneum, Oryzeaphilus spp., and Tenebroides mauritanicus were the pests of Carapa procera seeds and Lophira lanceolata fruits. Ephestia spp. was recorded as the main pest of both C. procera and L. lanceolata, whereas T. castaneum was only detected from seeds of L. lanceolata. For C. procera, the stocks were the most infested (29 %) by Ephestia spp. The infestation rate of fruits of L. lanceolata by Ephestia spp. on trees (31.42 ± 3.75 %) was less than the rate of fruits by T. castaneum on the ground (44.00 ± 3.5 %). The different body sizes of Ephestia spp. may indicate the occurrence of two putative species, one from C. procera and another one from L. lanceolata. This work provides important information that could contribute to the setting up of a local-scale sustainable management framework for oil tree pests in Burkina Faso and surrounding countries.     

Insecticidal activity of thiamethoxam against the bamboo powder post beetle <Emphasis Type="Italic">Dinoderus minutus</Emphasis> Fabr. (Coleoptera: Bostrichidae)

Thiamethoxam (ACTARA^® 25WG) was evaluated for its insecticidal activities against the bamboo powder post beetle Dinoderus minutus Fabricius (Coleoptera: Bostrichidae). The study showed that thiamethoxam had contact toxicity against D. minutus. Based on dose-mortality responses, LC₅₀ values for thiamethoxam against D. minutus ranged from 1.74 to 7.94 μg ml^?1. Laboratory and field exposure tests showed that thiamethoxam at concentration of atleast 10 μg ml^?1 may have anti-oviposition or anti-feeding effects on D. minutus and can protect post harvest Bambusa vulgaris Schrad. culms against the infestation of this bamboo boring beetle.     

Profiling of volatile compounds from five interior decoration timbers in Taiwan using TD/GC–MS/FID

Volatile organic compounds (VOCs) released from Chamaecyparis formosensis, Cryptomeria japonica, Cunninghamia lanceolata, Chamaecyparis obtusa var. formosana, and Taiwania cryptomerioides five major building and interior decoration timbers and their essential oil components were analyzed using GC–MS and TD/GC–MS/FID. Results showed that C. obtusa var. formosana had the highest yield of essential oil (3.42%), followed by C. formosensis (3.14%), while C. japonica had the lowest yield (0.95%). Moreover, oxygenated sesquiterpene was the highest relative content in all five essential oils and their main constituents were trans-myrtanol (18.04%), 1-epi-cubenol (15.99%), cedrol (62.26%), α-cadinol (26.42%), and α-cadinol (27.98%), respectively. In terms of emission quantity of top VOC, the results showed the decreasing order of C. formosensis (myrtenal, 74.21 mg/m²)?>?T. cryptomerioides (thujopsene, 12.00 mg/m²)?>?C. lanceolata (α-cedrene, 10.27 mg/m²)?>?C. obtusa var. formosana (α-pinene, 8.05 mg/m²)?>?C. japonica (α-cedrene, 4.25 mg/m²). C. formosensis had a greater amount of VOCs emitted and hence gave off more fragrance than C. obtusa var. formosana initially. However, after indoor exposure of 24 weeks, the VOC emission quantity of C. obtusa var. formosana exceeded that of C. formosensis. α-Cedrene and thujopsene were the top two major VOCs of both C. lanceolata and T. cryptomerioides. However, they both showed a trend of decrease in emission with prolonged exposure. All five plantation timbers showed good antifungal, antimicrobial, antibacterial, and antitermitic properties, making them ideal materials for interior decoration. Not only do they have strong bioactivities, they can also provide a fragrant and healthy living environment.     

Chemical ecology of <Emphasis Type="Italic">Halyomorpha halys</Emphasis>: discoveries and applications

There have been notable and significant advances in elucidating the chemical ecology of the invasive Halyomorpha halys (Hemiptera: Pentatomidae), brown marmorated stink bug. This highly destructive and polyphagous pest is originally from Korea, China, and Japan, but was accidentally introduced into North America and Europe. Prior to its invasion into these regions, little was known about its chemical ecology. However, since then, researchers have identified and synthesized its aggregation pheromone, documented its synergism with the pheromone of another Asian stink bug, Plautia stali, developed monitoring traps of various designs, and lures with reliable attractants have become commercially available. Furthermore, plant volatiles have been shown to have attractive, neutral, and repellent effects on attraction and retention of H. halys, and H. halys-derived volatiles have been shown to play a role in recruiting natural enemies. Finally, management strategies based on pheromone-based technology have been evaluated, including insecticide applications based on a cumulative threshold of adult captures in pheromone-baited traps, and the use of intensively baited trees in an attract-and-kill strategy to manage this pest. This review summarizes the available literature on the chemical ecology of H. halys and concludes with several research areas that should be explored in future research.     

Symptoms and fungi associated with elm trees decline in Iran

Elm (Ulmus, Ulmaceae) is one of the most popular and important trees in urban and landscape areas in Iran. A severe decline of elm trees has recently been observed in some areas of Kerman and Shiraz cities. However, the identity of the causal agents has not yet been investigated. The purpose of this study, carried out in the years 2012–2014, was to isolate and identify fungal trunk pathogens associated with decline symptoms observed in elm trees. Samples were collected from trunks and branches of trees showing various disease symptoms and internal wood lesions. Fungal isolations were made from discolored or decayed wood tissue. In Kerman some elm trees were attacked by the beetle Aeolesthes sarta; therefore, samples were also collected from larvae and adults of beetles associated with trees showing wood damage. Fungal isolates were identified by morphological, cultural and molecular characteristics. Thirteen fungal species, Phaeoacremonium (P.) minimum, P. parasiticum, P. sicilianum, P. alvesii, P. fraxinopennsylvanicum, Spencermartinsia viticola, Dothiorella (Do.) sarmentorum, Neoscytalidium hyalinum, Diatrype (Di.) whitmanensis, Cosmospora viridescens, Phoma (Pho.) herbarum, Phellinus (Phe.) tuberculosus and Inonotus levis were identified. Phaeoacremonium parasiticum was the only species isolated from both larvae and adult beetles. Pathogenicity trials were performed on detached shoots of elm under greenhouse conditions. Dothiorella sarmentorum was the most virulent species based on the length of wood necrosis. This study is the first report of P. sicilianum, C. viridescens and Phe. tuberculosus in Iran. In addition, most of the isolated species are reported for the first time on elm trees in the world.     

Heterotrophic components of biofilms on wood artefacts

Heterotrophic components of biofilms on wood artefacts were studied at the Conservation Laboratory for Wood Artefacts of the University Suor Orsola Benincasa of Naples, Italy. The aim of the study was to add new information on the micro-habitats represented by biofilms formed by wood-dwelling organisms. Light and electron microscopy of histological features of woods used to make the artefacts showed that the woods belonged to species of lime (Tilia sp.), poplar (Populus sp.) and pear (Pyrus sp.). A Denaturing Gradient Gel Electrophoresis analysis performed on heterotrophic microorganisms colonizing the artefacts led to identify four species of bacteria, namely Bacillus cereus, B. mycoides, B. subtilis and Microbacterium oleivorans, and seven species of fungi, namely Alternaria alternata, Aspergillus fumigans, A. versicolor, Cladosporium cladosporioides, C. oxysporum, Fusarium oxysporum and Penicillium chrysogenum. Based on its morphological features, an insect found on some artefacts was identified as the xylophagous beetle Nicobium castaneum (Anobiidae). The influence of wood type and environmental conditions on the diversity of microorganisms was discussed.