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I here review the potential effects of climate change on aphidophagous ladybirds and their future diversity. Aphidophagous ladybirds face challenges arising directly from climatic change and indirect challenges due to the effect of climate on their aphid prey and other organisms with which they interact. Ladybirds show at least some potential to respond to changes of climate through genetic change or phenotypic plasticity, notably through changes in colour pattern, dormancy and voltinism but also through thermal physiology and microhabitat or habitat plasticity. Phenological changes will likely occur in many aphidophagous species arising from relations with their prey. Changes in aphid abundance may lead to changes in ladybird prey associations over the season. The tendency to prey on multiple aphid species will insulate many ladybird predators from decline resulting from changes in the abundance of particular aphids. Like other insects, the geographic ranges of aphidophagous ladybird species will change as they track the climate. This is evidenced by the fossil record of ladybirds and by recent changes in ladybird biogeography. Such changes may be accompanied by a degree of thermal or phenological adaptation. It is likely that cold-adapted ladybirds and some island species will go extinct. Specialised species may also be threatened. A problem in assessing the threat to the latter is the minimal amount of research carried out on specialised species. In summary, aphidophagous ladybirds exhibit some potential resilience against climate change, but future climatic effects on their overall biodiversity are not fully clear.

Establishment and spread of invasive species can be facilitated by lack of natural enemies in the invaded area. Host-range evolution of natural enemies augments their ability to reduce the impact of the invader and could enhance their value for biological control. We assessed the potential of the Drosophila parasitoid, Leptopilina heterotoma (Hymenoptera: Figitidae), to exploit the invasive pest Drosophila suzukii by focusing on three performance indices: (i) attack rate; (ii) host killing, consisting of killing rate and lethal attack rate (killing efficiency); and (iii) successful offspring development (reproductive success). We found significant intraspecific variation in attack rate and killing rate and lethal attack rate among seven European populations, but offspring generally failed to successfully develop from the D. suzukii host. We crossed these European lines to create a genetically variable source population and performed a half-sib analysis to quantify genetic variation. Using a Bayesian animal model, we found that attack rate and killing rate had a heritability of h(2)=0.2, lethal attack rate h(2)=0.4, and offspring development h(2)=0. We then artificially selected wasps with the highest killing rate of D. suzukii for seven generations to test whether host-killing could be improved. There was a small and inconsistent response to selection in the three selection lines. Realized heritability (hr(2)) after four generations of selection was 0.17 but near zero after seven generations of selection. The genetic response might have been masked by an increased D. suzukii fitness resulting from adaptation to laboratory conditions. Our study reveals that native, European, L. heterotoma can attack the invasive pest, D. suzukii and significantly reduce fly survival and that different steps of the parasitization process need to be considered in the evolution of host-range. It highlights how evolutionary principles can be applied to optimize performance of native species for biological control.

Aim: The present study aimed to investigate the antifungal effects of fenhexamid, cyprodinil+fludioxanil, Bacillus subtilis QST 713, Trichoderma secondary metabolites (EGE-K-38 and EGE-K-71) on 6 isolates of necrotrophic fungi (Botrytis cinerea) under in- vitro conditions. Methodology: A dual culture technique was used to evaluate the effects of volatile compounds produced by Trichoderma in culture media against Botrytis cinerea isolates. For non-volatile and volatile metabolites, measurements for growth inhibition were made with the mixture of filter sterilized liquid medium of Trichoderma and potato dextrose agar. The fungicidal effects of these non-volatile metabolites and fungicides were first evaluated according to the effective concentration (EC50) data of growing mycelium inhibition of disease agents. Results: According to the results obtained, the drug/agent with the lowest fungicidal activity was determined as fenhexamide, which seems to have the lowest EC50 value of 0.05 ug m l-1. Both non-volatile metabolites and volatile metabolites of Trichoderma strains showed strong inhibition against B. cinerea isolates under experimental conditions. The highest growth inhibition percentage was determined with volatile metabolites of Trihoderma atroviride EGE-K-71 strain as 71.8%. Interpretation: The study suggest that filtrates that contain secondary metabolites and volatile compounds of Trichoderma strains produced in both liquid culture and dual culture conditions can be used as an effective fungal control agents against pre and postharvest contamination of grapes with Botrytis cinerea.

Mycoviruses are viruses that infect fungi, and hypovirulence-associated mycoviruses have the potential to control fungal diseases. However, it is unclear how mycovirus-mediated hypovirulent strains live and survive in the field, and no mycovirus has been applied for field crop protection. In this study, we found that a previously identified small DNA mycovirus (SsHADV-1) can convert its host, Sclerotinia sclerotiorum, from a typical necrotrophic pathogen to a beneficial endophytic fungus. SsHADV-1 downregulates the expression of key pathogenicity factor genes in S. sclerotiorum during infection. When growing in rapeseed, the SsHADV-1-infected strain DT-8 significantly regulates the expression of rapeseed genes involved in defense, hormone signaling, and circadian rhythm pathways. As a result, plant growth is promoted and disease resistance is enhanced. Field experiments showed that spraying DT-8 at the early flowering stage can reduce the disease severity of rapeseed stem rot by 67.6% and improve yield by 14.9%. Moreover, we discovered that SsHADV-1 could also infect other S. sclerotiorum strains on DT-8-inoculated plants and that DT-8 could be recovered from dead plants. These findings suggest that the mycoviruses may have the ability to shape the origin of endophytism. Our discoveries suggest that mycoviruses may influence the origin of endophytism and may also offer a novel strategy for disease control in which mycovirus-infected strains are used to improve crop health and release mycoviruses into the field.

Insects have been on the menu of humans for centuries, but only recently we have begun to mass produce them for human food and animal feed. This introduction first paints a synopsis of mass cultured insects and their application. The new insect production industry raises many interesting fundamental and applied questions about insect biology and fitness. The second part of the introduction to this special issue addresses the 13 articles dealing with the improvement of mass-rearing efforts for a range of insects. The various studies focus on the effects of diet and microorganisms on relevant life-history traits and economic value of the insects. They reflect the current rapid developments in the insect production industry.

Area-wide integrated pest management strategies against tephritid fruit flies include the release of fruit fly parasitic wasps in the target area. Mass rearing of parasitic wasps is essential for the efficient application of biological control strategies. Enhancement of fruit fly host fitness through manipulation of their gut-associated symbionts might also enhance the fitness of the produced parasitic wasps and improve the parasitoid rearing system. In the current study, we added three gut bacterial isolates originating from Ceratitis capitata (Wiedemann) and four originating from Bactrocera oleae (Rossi) (both Diptera: Tephritidae) to the larval diet of C. capitata and used the bacteria-fed larvae as hosts for the development of the parasitic wasp Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae). We evaluated the effect of the bacteria on wasp life-history traits and assessed their potential use for the improvement of D. longicaudata rearing. Enterobactersp. AA26 increased fecundity and parasitism rate and accelerated parasitoid emergence. Providencia sp. AA31 led to faster emergence of both male and female parasitoids, whereas Providencia sp. 22 increased the production of female progeny. Bacillus sp. 139 increased parasitoid fecundity, parasitism rate, and production of female progeny. Serratia sp. 49 accelerated parasitoid emergence for both males and females and increased production of female progeny. Klebsiella oxytoca delayed parasitoid emergence and Enterobacter sp. 23 decreased parasitoid fecundity and parasitism rate. Our findings demonstrate a wide range of effects of fruit fly gut symbionts on parasitoid production and reveal a great potential of bacteria use towards enhancement of parasitic wasp rearing.

Disease suppressive soils are important for managing soil-borne diseases that cannot be controlled with chemicals. One such disease is the potato common scab caused by Streptomyces species. Suppressiveness against common scab can develop spontaneously in fields where potato is grown for years without interruption, and this has been attributed to non-pathogenic Streptomyces strains. Streptomyces spp. have been used as inoculants in biological control, but their long-term effects have gained less attention. In our previous studies, a nonpathogenic Streptomyces strain (Str272) isolated from a potato common scab lesion suppressed common scab in field trials lasting over 5 years. In this study, bacterial communities in the tuberosphere i.e. in the soil adjacent to potato tubers, were analysed by next generation sequencing (NGS). The aim was to compare bacterial communities in untreated control plots to those in which seed tubers were treated with Str272 in one or several growing seasons. Str272 applications increased soil bacterial diversity and affected the bacterial composition in the potato tuberosphere. The most pronounced differences were observed between the untreated control and the treatments in which the antagonist had been applied in three or four consecutive years. The differences remained similar until the following growing season. Bacterial composition after repeated antagonist applications was associated with lower common scab severity. The antagonist applications had no or only slight effect on the number or abundance of OTUs belonging to Actinobacteria or Streptomyces, and no differences in quantities of pathogenic Streptomyces populations were detected by qPCR. This indicates that suppression of common scab by Str272 may not be based on direct effect on the common scab pathogens but is more likely to be associated with the alterations of the soil bacterial community. The most abundant bacteria phyla in the potato tuberosphere were Actinobacteria, Proteobacteria and Acidobacteria. However, the OTUs responding greatest to the antagonist treatments belonged to Bacterioidetes and Gemmatimonadetes. Results indicate that repeated applications of Str272 can change the bacterial community in the potato tuberosphere and lead to development of soil that is suppressive against potato common scab for several growing seasons after the last application.

Corn earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), has emerged as an injurious insect pest to hemp, Cannabis sativa L., a crop newly reintroduced to the United States. Growing hemp presents a potential alternative economic opportunity for farmers but can be challenging with a market that is unstable and just developing. One of the most notable production challenges is managing corn earworm, an insect pest that is particularly damaging when it feeds on flower buds produced in cannabinoid varieties, creating extensive bud tunneling and wounds that allow entry of pathogens that can aid development and presence of bud rot. Damage to seeds is of lesser concern in hemp cultivars grown for grain and minimal risk is associated with hemp grown for fiber. Our ability to research hemp has only recently been allowed as production was largely suspended following World War II and, as such, there has been limited opportunity to develop information for empirically-based pest management recommendations. Further complicating development of integrated pest management (IPM) strategies are regulatory challenges associated with providing registration support to add hemp to pesticide labels, as it was not formally recognized as a crop by U.S. regulatory agencies until late 2019. Research needs and challenges to develop effective IPM programs for corn earworm on hemp are discussed here.

Trihoderma citrinoviride protects plants from diseases by functioning as antagonists of many pathogenic fungi or by triggering the antioxidant defense system in plants. In the present study, to uncover the possible alleviative role of Trichoderma against salinity and Rhizoctonia solani infection, strawberry plants were pretreated Trichoderma citrinoviride and then subjected to salinity, R. solani and combined salinity and R. solani. The effect of T. citrinoviride on the alleviation of the effects of salt stress and Rhizoctonia solani infection was investigated by analysing leaf dry weight, PSII efficiency, and the activity of some antioxidant enzymes in the leaves of strawberry plants. T. citrinoviride improved competitive capability against salinity and R. solani infection. It showed 79% inhibition of the growth of pathogen R. solani. T. citrinoviride reduced 63% of the severity of disease in the leaves. Trichoderma pretreatment maximized plant dry weight. The T. citrinoviride-pretreated plants showed higher levels of PSII efficiency (Fv/Fm). Decreased lipid peroxidation and H2O2 accumulation compared to untreated seedlings under salt stress and R. solani infection was observed. Trichoderma-pretreated and –untreated plants respond differently to salt stress and R. solani infection by means of antioxidant defense. As compared to untreated seedlings, treated seedlings showed significantly lower activities of antioxidant enzymes, superoxide dismutase (SOD), peroxidase (POX), cell wall peroxidase (CWPOX) under salt stress and R. solani infection, indicating that treated seedlings might sense lower stress as compared to untreated seedlings. The study reports the effective adaptive strategy and potential of T. citrinoviride in alleviating the negative impact of salt stress and R. solani infection in strawberry.

There is growing evidence about the role of insectivorous bats against agricultural pests in various crops. Nevertheless, little research addressed the aggregational and functional responses of bat assemblages to changes in pest availability across a spatio-temporal scale. Therefore, we examined the activity and diet habits of different bat species using DNA metabarcoding by simultaneously monitoring the relative abundance of two major pests (the European grapevine moth, Lobesia botrana, and the leaf rolling tortrix, Sparganothis pilleriana) through the grape growing season, in a vineyard region of the Iberian Peninsula. During pest major irruptions, we found the highest bat activity levels and frequencies of grape pests in the diet of bats, although not all bat species contributed equally to pest suppression. Bats of different foraging guilds positively responded to pest abundances, indicating distinct bat species may synergistically play a role at suppressing agricultural pests at broad scales of the aerospace. For instance, narrow space foragers exploiting major irruptions in grape interior, edge space foragers hampering pest dispersion at local scale, and open space foragers preventing infestations of new grapevine patches at broader scales. Yet, our study exposed the current methodological constraints regarding pest dispersion dynamics, acoustic monitoring of bats? foraging activity or the unfeasibility of metabarcoding to reliably quantify prey abundance in bats diet, and thus further improvement in these issues is required in order to gain insight on the agroecological interactions between bats and pests. We are grateful to owners of the winery cellars (Artadi, Berarte, Laukote, Puelles, Ramon Saenz, Granja Nuestra Senora de Remelluri and R. Lopez de Heredia Vina Tondonia) for facilitating the collection of faeces and for allowing us to conduct the experiments on their estates. We also thank Ana Maria Diez Navajas and NEIKER-Tecnalia workers for sending data on the phenology of L. botrana during the sampling period. Special gratitude to Gonzalo Garcia Baquero for his valuable help with statistical analysis and Vanessa A. Mata for her priceless advice on modeling and the Sequencing and Genotyping Unit-Genomic Facilities-SGIker (UPV/EHU/ERDF, EU) for the technical support provided. This project was funded by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund (CGL-2015-69069P), as well as the Government of the Basque Country (IT75413 and IT1163-19). The Basque Government granted UB (PRE_2019_2_0186).

The antagonistic activities of native Debaryomyces hansenii strains isolated from Danish cheese brines were evaluated against contaminating molds in the dairy industry. Determination of chromosome polymorphism by use of pulsed-field gel electrophoresis (PFGE) revealed a huge genetic heterogeneity among the D. hansenii strains, which was reflected in intra-species variation at the phenotypic level. 11 D. hansenii strains were tested for their ability to inhibit germination and growth of contaminating molds, frequently occurring at Danish dairies, i.e., Cladosporium inversicolor, Cladosporium sinuosum, Fusarium avenaceum, Mucor racemosus, and Penicillium roqueforti. Especially the germination of C. inversicolor and P. roqueforti was significantly inhibited by cell-free supernatants of all D. hansenii strains. The underlying factors behind the inhibitory effects of the D. hansenii cell-free supernatants were investigated. Based on dynamic headspace sampling followed by gas chromatography-mass spectrometry (DHS-GC-MS), 71 volatile compounds (VOCs) produced by the D. hansenii strains were identified, including 6 acids, 22 alcohols, 15 aldehydes, 3 benzene derivatives, 8 esters, 3 heterocyclic compounds, 12 ketones, and 2 phenols. Among the 71 identified VOCs, inhibition of germination of C. inversicolor correlated strongly with three VOCs, i.e., 3-methylbutanoic acid, 2-pentanone as well as acetic acid. For P. roqueforti, two VOCs correlated with inhibition of germination, i.e., acetone and 2-phenylethanol, of which the latter also correlated strongly with inhibition of mycelium growth. Low half-maximal inhibitory concentrations (IC50) were especially observed for 3-methylbutanoic acid, i.e., 6.32–9.53 × 10–5 and 2.00–2.67 × 10–4 mol/L for C. inversicolor and P. roqueforti, respectively. For 2-phenylethanol, a well-known quorum sensing molecule, the IC50 was 1.99–7.49 × 10–3 and 1.73–3.45 × 10–3 mol/L for C. inversicolor and P. roqueforti, respectively. For acetic acid, the IC50 was 1.35–2.47 × 10–3 and 1.19–2.80 × 10–3 mol/L for C. inversicolor and P. roqueforti, respectively. Finally, relative weak inhibition was observed for 2-pentanone and acetone. The current study shows that native strains of D. hansenii isolated from Danish brines have antagonistic effects against specific contaminating molds and points to the development of D. hansenii strains as bioprotective cultures, targeting cheese brines and cheese surfaces.

The pine bark adelgid, Pineus strobi (Hartig) (Hemiptera: Adelgidae), is an herbivore native to eastern North America that specialises on eastern white pine, Pinus strobus Linnaeus (Pinaceae). Little is known about P. strobi, especially in its southern range in the Appalachian Mountains, United States of America, and the composition of its predator complex has not yet been documented in this region. The current study identifies arthropod predators associated with P. strobi in Appalachian forests of Virginia based on a two-year survey. Predators were identified using morphology and DNA barcoding. Predator species include: Laricobius rubidus LeConte (Coleoptera: Derodontidae), Leucopis piniperda Malloch (Diptera: Chamaemyiidae), and Leucopis argenticollis Zetterstedt (Diptera: Chamaemyiidae), that are known adelgid specialists. Also found were predators from the families Cecidomyiidae (Diptera), Coccinellidae (Coleoptera), Chrysopidae (Neuroptera), Hemerobiidae (Neuroptera), and Syrphidae (Diptera). The Cecidomyiidae were especially diverse, with 14 different species inferred from their DNA barcodes. Knowledge of this predator complex is particularly valuable for anticipation and detection of potential interactions between native predator species and those that are being considered for the introduction for biological control of invasive adelgid pests within the southern Appalachian ecosystem.

Fusarium basal rot (FBR) is a soil-borne disease that affects Allium species worldwide. Although FBR has long been recognized as a major constraint to the production of economically important Allium species, information that could support disease management remains scattered. In this review, the current knowledge on the causal agents, symptomology and epidemiology, impact, and management strategies of FBR is synthesized. We highlight that FPR is associated with different complexes of several Fusarium species, of which Fusarium oxysporum and F. proliferatum are the most prevalent. These pathogenic complexes vary in composition and virulence, depending on sites and hosts, which can be challenging for disease management. Research to improve disease management using chemical pesticides, resistance cultivars, biocontrol agents, and cultural practices has achieved both promising results and limitations. Finally, research needs and future directions are proposed for the development of effective FBR management strategies.

Biochar has been reported to play a positive role in disease suppression against airborne pathogens in plants. The mechanisms behind this positive trait are not well-understood. In this study, we hypothesized that the attraction of plant growth-promoting rhizobacteria (PGPR) or fungi (PGPF) underlies the mechanism of biochar in plant protection. The attraction of PGPR and PGPF may either activate the innate immune system of plants or help the plants with nutrient uptake. We studied the effect of biochar in peat substrate (PS) on the susceptibility of strawberry, both on leaves and fruits, against the airborne fungal pathogen Botrytis cinerea. Biochar had a positive impact on the resistance of strawberry fruits but not the plant leaves. On leaves, the infection was more severe compared with plants without biochar in the PS. The different effects on fruits and plant leaves may indicate a trade-off between plant parts. Future studies should focus on monitoring gene expression and metabolites of strawberry fruits to investigate this potential trade-off effect. A change in the microbial community in the rhizosphere was also observed, with increased fungal diversity and higher abundances of amplicon sequence variants classified into Granulicella, Mucilaginibacter, and Byssochlamys surrounding the plant root, where the latter two were reported as biocontrol agents. The change in the microbial community was not correlated with a change in nutrient uptake by the plant in either the leaves or the fruits. A decrease in the defense gene expression in the leaves was observed. In conclusion, the decreased infection of B. cinerea in strawberry fruits mediated by the addition of biochar in the PS is most likely regulated by the changes in the microbial community.

In this study, which was conducted to determine predation potential of Typhlodromus recki Wainstein, 1958 (Acari: Phytoseiidae) at Ege University, Faculty of Agriculture, Department of Plant Protection in 2018-2019. Functional response and egg production of the predatory mite, T. recki fed on different biological stages (egg, larva, protonymph, deutonymph and adult male) of the two-spotted spider mite (green form), Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) were studied under laboratory conditions (25 +/- 1 degrees C, 60 +/- 10% RH and 16:8 h L:D photoperiod). In the experiments, seven prey densities (2, 4, 8, 16, 32, 64 and 128) for each biological stage of the prey were offered daily to the predatory mite. The results of logistic regression analysis indicated that T. recki had a Type II functional response on each developmental stage of its prey according to Holling's models. The attack rate (alpha) and the handling time (T-h) varied based on the biological stages of the prey. The highest alpha and the lowest T-h values were determined as 1.035 and 0.001 when the predator fed on larvae and eggs of its prey, respectively. The highest average daily mean number of the eggs consumed by T. recki was 111 at 128 prey densities. The highest average daily mean number of eggs deposited by the predator were found to be 1.05 when it fed on the eight-prey density of T. urticae protonymphs. In addition, the lowest average daily mean number of eggs deposited by the predator was 0.15 when fed on the two-prey density with T. urticae adult males. The study indicates that T. recki could be effective and promising biological control agent for T. urticae., Scientific and Technological Research Council of Turkey [118O666], This study was supported by the Scientific and Technological Research Council of Turkey (TUBITAK-Project Number: 118O666) . I am grateful to Dr. Ibrahim Cakmak (Aydn Adnan Menderes University, Faculty of Agriculture, Department of Plant Protection, Aydn, Turkey) and Dr. smail Doker (Cukurova University, Faculty of Agriculture, Department of Plant Protection, Adana, Turkey) for data analyses and editing the manuscript.

An infective prey has the potential to infect, kill and consume its predator. Such a prey-predator relationship fundamentally differs from the predator-prey interaction because the prey can directly profit from the predator as a growth resource. Here we present a population dynamics model of partial role reversal in the predator-prey interaction of two species, the bottom dwelling marine deposit feeder sea cucumber Apostichopus japonicus and an important food source for the sea cucumber but potentially infective bacterium Vibrio splendidus. We analyse the effects of different parameters, e.g. infectivity and grazing rate, on the population sizes. We show that relative population sizes of the sea cucumber and V. Splendidus may switch with increasing infectivity. We also show that in the partial role reversal interaction the infective prey may benefit from the presence of the predator such that the population size may exceed the value of the carrying capacity of the prey in the absence of the predator. We also analysed the conditions for species extinction. The extinction of the prey, V. splendidus, may occur when its growth rate is low, or in the absence of infectivity. The extinction of the predator, A. japonicus, may follow if either the infectivity of the prey is high or a moderately infective prey is abundant. We conclude that partial role reversal is an undervalued subject in predator-prey studies.

Feeding a rising population of currently 7.8 billion people globally requires efficient agriculture, which is preferably sustainable. Today, farmers are largely dependent on synthetic fungicides to avoid food losses caused by fungal diseases. However, the extensive use of these has resulted in the emergence of fungicide-resistant pathogens and concerns have been raised over the residual effects on the environment and human health. In this regard, biocontrol agents (BCAs) have been proposed as an alternative to standard fungicides but their disease management capacity is usually incomplete and heavily relies on uncontrollable environmental conditions. An integrated approach combining BCAs with fungicides, which is the focus of this review, is put forward as a way to reduce the fungicide doses to manage plant diseases and thereby their residue on harvested crops. In addition, such a strategy of combining antifungal treatments with different modes of action reduces the selection pressure on pathogens and thereby the chances of resistance development. However, to allow its large-scale implementation, further knowledge is needed, comprising timing, number and interval of repeated BCA applications and their compatibility with fungicides. The compatibility of BCAs with fungicides might differ when applied in a mixture or when used in alternation. ispartof: MICROORGANISMS vol:8 issue:12 ispartof: location:Switzerland status: published

Harmonia axyridis is an invasive alien ladybird in North America and Europe. Studies show that multiple natural enemies are using Ha. axyridis as a new host. However, thus far, no research has been undertaken to study the effects of simultaneous infections of multiple natural enemies on Ha. axyridis. We hypothesized that high thallus densities of the ectoparasitic fungus Hesperomyces virescens on a ladybird weaken the host’s defenses, thereby making it more susceptible to infection by other natural enemies. We examined mortality of the North American-native Olla v-nigrum and Ha. axyridis co-infected with He. virescens and an entomopathogenic fungus—either Beauveria bassiana or Metarhizium anisopliae. Laboratory assays revealed that He. virescens-infected O. v-nigrum individuals are more susceptible to entomopathogenic fungi, but Ha. axyridis does not suffer the same effects. This is in line with the enemy release hypothesis, which predicts that invasive alien species in new geographic areas experience reduced regulatory effects from natural enemies compared to native species. Considering our results, we can ask how He. virescens affects survival when confronted by other pathogens that previously had little impact on Ha. axyridis.

We studied the food quality of the aphid Rhopalosiphum padi to the pirate bug Orius majusculus using Ephestia eggs as high-quality comparison prey. Several performance parameters were tested on individuals that had been reared and maintained on each of the two single-prey diets or on a mixed diet. All fitness parameters were lower in individuals fed aphids only, indicating poor food quality of this prey. Compared with the pure Ephestia egg diet, the mixed diet enhanced teneral mass, while adult survival and female starvation tolerance were negatively affected and all other traits were unaffected. Body protein proportions were constant across diets, whereas lipid proportion was low in the aphid treatment. Preference for aphids was lower following a monotypic aphid diet than when reared on Ephestia eggs or a mixed diet. The results confirm that R. padi is low-quality food for O. majusculus as it is for other generalist predators, even though O. majusculus may contribute significantly to population suppression of the aphid.

Sphecophaga vesparum often parasitizes nests of vespid wasps such as Vespula vulgaris and Vespula germanica. Inside the colonies, the ectoparasitic larvae feed on the immature forms of the wasps. There are two adult forms of S. vesparum. The large, winged adults emerge from either rigid yellow cocoons or the orange cocoons used for overwintering. The small, brachypterous females emerge from soft, white cocoons. The species is facultative deuterotokous, producing mostly parthenogenic females and infrequently producing males. Here, we describe the production of chemical compounds related to the different developmental forms of the parasitoid S. vesparum (larvae, pupae and adults). We also compare the chemical profiles of the parasitoid wasp adults to those of their two main host species, Vespula vulgaris and Vespula germanica. The results show differences in hydrocarbon composition of larvae, pupae and adults of S. vesparum. Our results also suggest a partial mimicry of each of the two host species, mostly relating to linear alkanes present in both parasitoids and the host vespid wasp species. This matching is likely due to the recycling of the prey&rsquo, s hydrocarbons, as has been found in other species of parasitoids.

Rhizocephalans are abundant members of marine ecosystems and are important regulators of crustacean host populations. Morphological and ecological variation makes them an attractive system for evolutionary studies of advanced parasitism. Such studies have been impeded by a largely formalistic taxonomy, because rhizocephalan morphology offers no characters for a robust phylogenetic analysis. We use DNA sequence data to estimate a new phylogeny for 43 species and use this to develop a revised taxonomy for all Rhizocephala. Our taxonomy accepts 13 new or redefined monophyletic families. The traditional subdivision into the suborders Kentrogonida and Akentrogonida is abandoned, because both are polyphyletic. The three ‘classical’ kentrogonid families are also polyphyletic, including the species-rich Sacculinidae, which is split into a redefined and a new family. Most species of large families remain to be studied based on molecular evidence and are therefore still assigned to their current genus and family by default. We caution against undue generalizations from studies on model species until a more stable species-level taxonomy is also available, which requires more extensive genus- and species-level sampling with molecular tools. We briefly discuss the most promising future studies that will be facilitated by this new phylogeny-based taxonomy.

Alfalfa weevil (Hypera postica Gyllenhal, 1813) samples were collected from different locations in Kirsehir, Turkey, during May-August in 2014. They were immediately transferred to the research laboratory and dissected under aseptic conditions. Then serial dilutions were prepared from digestive tract samples and the spread plate technique was used for obtaining pure cultures. The conventional and molecular methods that include morphological and physiological examinations, biochemical tests, 16S rDNA sequencing, and the basic local alignment search tool (BLAST) were used for identification of the bacterial isolates. According to the findings of the present study, the YHH-2 isolate was found as the main pathogenic bacterium that dominates the digestive tract microflora of the alfalfa weevil. 16S rDNA sequencing and the BLAST data revealed that YHH-2 showed 100% similarity to Bacillus pumilus, recently described as an entomopathogenic strain. In conclusion, the results of the present study are important due to showing for the first time the presence of Bacillus pumilus Y HH-2 in the digestive tract of the alfalfa weevil and it may be used as a potential biocontrol agent against the harmful effects of this insect species., Ahi Evran University Research Fund [4003/2.13.002, 201, 2013], This work was supported by the Ahi Evran University Research Fund (Project Number: 4003/2.13.002, 201, 2013).

New genetic control methods for mosquitoes may reduce vector species without direct effects on other species or the physical environment common with insecticides or drainage. Effects on predators and competitors could, however, be a concern as Anopheles gambiae s.l. is preyed upon in all life stages. We overview the literature and assess the strength of the ecological interactions identified. Most predators identified consume many other insect species and there is no evidence that any species preys exclusively on any anopheline mosquito. There is one predatory species with a specialisation on blood‐fed mosquitoes including An. gambiae s.l.. Evarcha culicivora is a jumping spider, known as the vampire spider, found around Lake Victoria. There is no evidence that these salticids require Anopheles mosquitoes and will readily consume blood‐fed Culex. Interspecific competition studies focus on other mosquitoes of larval habitats. Many of these take place in artificial cosms and give contrasting results to semi‐field studies. This may limit their extrapolation regarding the potential impact of reduced An. gambiae numbers. Previous mosquito control interventions are informative and identify competitive release and niche opportunism; so while the identity and relative abundance of the species present may change, the biomass available to predators may not.

Endophytic bacteria (EB) are ubiquitous in most plant species and they colonize plant tissues actively and systemically. Their colonization and persistence in the plant may be crucial to plant growth, yield and suppressing diseases. In this study, the long-term population dynamics of the two EB, namely Ochrobactrum spp. strain CB36/1 and Pantoea agglomerans strain CC37/2 in cucumber plants (Cucumis sativus L. cv. Gordion F1), were monitored. Also, the potential effects of these EB on plant growth, fruit quality, and yield, as well as the influences on Angular leaf spot disease of cucumber (ALS) and the yield under the disease pressure, were investigated. Plants were grown using the soilless cultivation technique in the greenhouse. Inoculation of the EB took place twice, and their population in plant tissues were monitored periodically for 62 days. Both EB isolates survived in plant organs until the end of the growing season, but over time, population densities dropped from 105 to 103 CFU g. plant?1 with the age of the plant. The EB applications had significant effects on fruit length, color and firmness. Total yield increased by 22% with CB36/1 and 21% with CC37/2 without disease pressure. Only CC37 / 2 significantly reduced the severity of ALS disease by 41% and increased yield by 22% compared to pathogen treatment alone. In this study, it was observed that the EB strain CC37/2 might contribute to reducing the chemical input and prevent the yield losses in soilless growing systems within the integrated agricultural concept. © 2021 Elsevier B.V., FA1103 Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, TÜBITAK: TUBITAK-COST 111 O 505, The present study was sponsored by national grants from the Scientific and Technological Research Council of Turkey (TUBITAK-COST 111 O 505) and Ege University Science-Technology Research and Application Center (EBILTEM). The authors express their gratitude for the contribution of the participants in EU-COST Action FA1103., The present study was sponsored by national grants from the Scientific and Technological Research Council of Turkey ( TUBITAK-COST 111 O 505 ) and Ege University Science-Technology Research and Application Center ( EBILTEM ). The authors express their gratitude for the contribution of the participants in EU-COST Action FA1103.

Plant root secreted compounds alter the gene expression of associated microorganisms by acting as signal molecules that either stimulate or repel the interaction with beneficial or harmful species, respectively. However, it is still unclear whether two distinct groups of beneficial bacteria, non-plant-associated (soil) strains and plant-associated (endophytic) strains, respond uniformly or variably to the exposure with root exudates. Therefore, Bacillus mycoides, a potential biocontrol agent and plant growth-promoting bacterium, was isolated from the endosphere of potatoes and from soil of the same geographical region. Confocal fluorescence microscopy of plants inoculated with GFP-tagged B. mycoides strains showed that the endosphere isolate EC18 had a stronger plant colonization ability and competed more successfully for the colonization sites than the soil isolate SB8. To dissect these phenotypic differences, the genomes of the two strains were sequenced and the transcriptome response to potato root exudates was compared. The global transcriptome profiles evidenced that the endophytic isolate responded more pronounced than the soil-derived isolate and a higher number of significant differentially expressed genes were detected. Both isolates responded with the alteration of expression of an overlapping set of genes, which had previously been reported to be involved in plant-microbe interactions; including organic substance metabolism, oxidative reduction, and transmembrane transport. Notably, several genes were specifically upregulated in the endosphere isolate EC18, while being oppositely downregulated in the soil isolate SB8. These genes mainly encoded membrane proteins, transcriptional regulators or were involved in amino acid metabolism and biosynthesis. By contrast, several genes upregulated in the soil isolate SB8 and downregulated in the endosphere isolate EC18 were related to sugar transport, which might coincide with the different nutrient availability in the two environments. Altogether, the presented transcriptome profiles provide highly improved insights into the life strategies of plant-associated endophytes and soil isolates of B. mycoides.

Fusarium root rot is a major cryptogamic disease in olive trees caused by the soil-borne fungus Fusarium solani. Controlling this disease requires the extensive use of chemicals. However, using BCAs such as some Trichoderma strains may be an opportune alternative to fungicides in protecting olive plantations. A new isolate (Fso14) was isolated from young olive trees showing severe dieback symptoms. The objective of this work was to analyze the biocontrol behavior of a Tunisian strain of T. harzianum (Ths97) on olive trees against Fso14 by assessing both mycoparasitic activity (in planta and in vitro) and ability to locally modulate different gene-related defenses of the plant. Ths97 was found to inhibit Fso14 growth in vitro. Optical microscopic analysis at the confrontation zone between hyphae showed that Ths97 grew alongside Fso14 with numerous contact points suggesting parasitic activity. On olive trees, Ths97 developed a strong protective role against root infestation by Fso14, whether inoculated before or after the pathogenic agent. When inoculated alone, Fso14 and Ths97 did not modulate (or only slightly with inhibitions or inductions, respectively) the expression of genes involved in plant immunity (oxidative stress, phenylpropanoid pathway, PR-proteins and JA/Et-SA hormonal status). However, when Ths97 was inoculated in combination with Fso14, several defense-related genes were highly up-regulated, indicating probable primed-plant events. These promising results provided valuable information on using Ths97 as a beneficial agent to control fusarium root rot disease caused by F. solani in olive trees.

The entomopathogenic fungus Beauveria bassiana is able to colonize and establish a symbiotic relationship with plants as an endophyte, naturally as well as through artificial inoculation. This study aims at implementing a reliable and efficient method to establish endophytic B. bassiana in maize plants. The level of the endophytic establishment was evaluated and the survival and fecundity of the English grain aphid (Sitobion avenae) was investigated. Eight-days-old maize plants were sprayed with a fungal spore suspension, while control plants were treated only with a Tween solution. Two weeks after inoculation, seven clip cages per plant, each containing an adult aphid, were attached to different leaves and left for seven days. All inoculated plants contained endophytic B. bassiana as confirmed by plating surface disinfected leaf pieces on selective plates. None of the control plants showed growth of B. bassiana. The highest colonization levels were 61% in older inoculated leaves and 19% in younger non-inoculated leaves. The survival of S. avenae on inoculated plants was reduced up to 49% as compared to control plants. Dead aphids did not show any signs of mycosis. The number of nymphs produced by a single aphid was reduced up to 70% and 74% on inoculated and non-inoculated leaves, respectively. Presence of endophytic B. bassiana in non-inoculated younger leaves implies the movement of the endophyte inside plants. The negative effect on aphid fecundity appears to be systemic as implied by the almost equal reduction of mean numbers of nymphs produced on older and younger leaves on the inoculated plants, irrespective of the level of colonization by endophytic B. bassiana.

Beneficial Pseudomonas spp. produce an array of antimicrobial secondary metabolites such as cyclic lipopeptides (CLPs). We investigated the capacity of CLP-producing Pseudomonas strains and their crude CLP extracts to control rice blast caused by Magnaporthe oryzae, both in a direct manner and via induced systemic resistance (ISR). In planta biocontrol assays showed that lokisin-, white line inducing principle (WLIP)-, entolysin- and N3-producing strains successfully induced resistance to M. oryzae VT5M1. Furthermore, crude extracts of lokisin, WLIP and entolysin gave similar ISR results when tested in planta. In contrast, a xantholysin-producing strain and crude extracts of N3, xantholysin and orfamide did not induce resistance against the rice blast disease. The role of WLIP in triggering ISR was further confirmed by using WLIP-deficient mutants. The severity of rice blast disease was significantly reduced when M. oryzae spores were pre-treated with crude extracts of N3, lokisin, WLIP, entolysin or orfamide prior to inoculation. In vitro microscopic assays further revealed the capacity of crude N3, lokisin, WLIP, entolysin, xantholysin and orfamide to significantly inhibit appressoria formation by M. oryzae. In addition, the lokisin and WLIP biosynthetic gene clusters in the producing strains are described. In short, our study demonstrates the biological activity of structurally diverse CLPs in the control of the rice blast disease caused by M. oryzae. Furthermore, we provide insight into the non-ribosomal peptide synthetase genes encoding the WLIP and lokisin biosynthetic machineries. ispartof: FRONTIERS IN PLANT SCIENCE vol:10 ispartof: location:Switzerland status: published

Globally, Anastatus species (Hymenoptera: Eupelmidae) are associated with the invasive agricultural pest Halyomorpha halys (Stal) (Hemiptera: Pentatomidae). In Europe, the polyphagous Anastatus bifasciatus (Geoffroy) is the most prevalent native egg parasitoid on H. halys eggs and is currently being tested as a candidate for augmentative biological control. Anastatus bifasciatus frequently displays behavior without oviposition, and induces additional host mortality through oviposition damage and host feeding that is not measured with offspring emergence. This exacerbates accurate assessment of parasitism and host impact, which is crucial for efficacy evaluation as well as for pre- and post-release risk assessment. To address this, a general Anastatus primer set amplifying a 318-bp fragment within the barcoding region of the cytochrome oxidase I (COI) gene was developed. When challenged with DNA of three Anastatus species -A. bifasciatus, Anastatus japonicus Ashmead, and Anastatus sp.-, five scelionid parasitoid species that might be encountered in the same host environments and 11 pentatomid host species, only Anastatus DNA was successfully amplified. When applied to eggs of the target host, H. halys, and an exemplary non-target host, Dendrolimus pini L. (Lepidoptera: Lasiocampidae), subjected to host feeding, no Anastatus amplicons were produced. Eggs of the two host species containing A. bifasciatus parasitoid stages, from 1-h-old eggs to pupae, and emerged eggs yielded Anastatus fragments. Confirmation of parasitoid presence with dissections and subsequent PCRs with the developed primer pair resulted in 95% success for 1-h-old parasitoid eggs. For both host species, field-exposed sentinel emerged eggs stored dry for 6 months, 100% of the specimens produced Anastatus amplicons. This DNA-based screening method can be used in combination with conventional methods to better interpret host-parasitoid and parasitoid-parasitoid interactions. It will help address ecological questions related to an environmentally friendly approach for the control of H. halys in invaded areas.

In this study, molecular (ribosomal sequence data), morphological and cross-hybridization properties were used to identify a newSteinernemasp. from Florida, USA. Molecular and morphological data provided evidence for placing the novel species into Clade V, or the ‘glaseri-group’ ofSteinernemaspp. Within this clade, analysis of sequence data of the rDNA genes, 28S and internal transcribed spacer (ITS), depicted the novel species as a distinctive entity and closely related toS. glaseriandS. cubanum.Additionally, cross-hybridization assays showed that the new species is unable to interbreed with either of the latter two species, reinforcing its uniqueness from a biological species concept standpoint. Key morphological diagnostic characters forS. khuongin. sp. include the mean morphometric features of the third-stage infective juveniles: total body length (average: 1066 μm), tail length (average: 65 μm), location of the excretory pore (average: 80.5 μm) and the values ofc(average: 16.4),D% (average: 60.5),E% (average: 126) andH% (average: 46.6). Additionally, males can be differentiated fromS. glaseriandS. cubanumby the values of several ratios:D% (average: 68),E% (average: 323) and SW% (average: 120). The natural distribution of this species in Florida encompasses both natural areas and citrus groves, primarily in shallow groundwater ecoregions designated as ‘flatwoods’. The morphological, molecular, phylogenetic and ecological data associated with this nematode support its identity as a new species in theS. glaseri-group.

In hymenopterans, males are normally haploid (1n) and females diploid (2n), but individuals with divergent ploidy levels are frequently found. In species with ‘complementary sex determination’ (CSD), increasing numbers of diploid males that are often infertile or unviable arise from inbreeding, presenting a major impediment to biocontrol breeding. Non‐CSD species, which are common in some parasitoid wasp taxa, do not produce polyploids through inbreeding. Nevertheless, polyploidy also occurs in non‐CSD Hymenoptera. As a first survey on the impacts of inbreeding and polyploidy of non‐CSD species, we investigate life‐history traits of a long‐term laboratory line of the parasitoid Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae) (‘Whiting polyploid line’) in which polyploids of both sexes (diploid males, triploid females) are viable and fertile. Diploid males produce diploid sperm and virgin triploid females produce haploid and diploid eggs. We found that diploid males did not differ from haploid males with respect to body size, progeny size, mate competition, or lifespan. When diploid males were mated to many females (without accounting for mating order), the females produced a relatively high proportion of male offspring, possibly indicating that these males produce less sperm and/or have reduced sperm functionality. In triploid females, parasitization rate and fecundity were reduced and body size was slightly increased, but there was no effect on lifespan. After one generation of outbreeding, lifespan as well as parasitization rate were increased, and a body size difference was no longer apparent. This suggests that outbreeding has an effect on traits observed in an inbred polyploidy background. Overall, these results indicate some phenotypic detriments of non‐CSD polyploids that must be taken into account in breeding.

Temperature influences biological processes of ectotherms including ecological interactions, but interaction strengths may depend on species-specific traits. Furthermore, ectotherms acclimate to prevailing thermal conditions by adjusting physiological parameters, which often implies costs to other fitness-related parameters. Both predators and prey may therefore pay thermal acclimation costs following exposure to suboptimal temperatures. However, these costs may be asymmetrical between predator and prey, and between the predator and different species of concurrent prey. We investigated whether thermal pre-exposure affected subsequent kill rate and predator fitness when foraging on prey that differ in ease of capture, and whether changes were primarily caused by predator or by prey pre-exposure effects. Specifically, we were interested in whether there were interactions between predator pre-exposed temperature and specific prey. Using the mesostigmatid mite Gaeolaelaps aculeifer as a generalist predator and the collembolans Folsomia candida and Protaphorura fimata as prey, we measured the impact of present temperature, predator pre-exposure temperature, prey pre-exposure temperature (all 10 or 20°C), prey species, and all interactions on prey numbers killed, predator eggs produced, and exploitation of killed prey in a full factorial design. Mites killed P. fimata in equal numbers independent of the presence of F. candida, but killed F. candida when P. fimata was absent. Mite kill rate and reproduction were significantly affected by mite pre-exposure temperature and test temperature, but not by prey pre-exposure temperature. Significantly more of the slower prey was killed than of the quicker prey. Importantly, we found significant synergistic negative interaction effects between predator cold pre-exposure and hunting prey of higher agility on predator kill rate and reproduction. Our findings show that the negative effects of cold and cold pre-exposure on kill rate and reproduction may be more severe when predators forage on quick prey. The study implies that predator cold exposure has consequences for specific prey survival following cold due to altered predation pressures, which in nature should influence the specific prey population dynamics and apparent competition outcomes. The findings exemplify how not only current but also preceding conditions affect ecological interactions, and that effect strength depends on the species involved.

International audience; Cocoyam (Xanthosoma sagittifolium (L.)), an important tuber crop in the tropics, is severely affected by the cocoyam root rot disease (CRRD) caused by Pythium myriotylum. The white cocoyam genotype is very susceptible while the red cocoyam has some field tolerance to CRRD. Fluorescent Pseudomonas isolates obtained from the rhizosphere of healthy red and white cocoyams from three different fields in Cameroon were taxonomically characterized. The cocoyam rhizosphere was enriched with P. fluorescens complex and P. putida isolates independent of the plant genotype. LC–MS and NMR analyses revealed that 50% of the Pseudomonas isolates produced cyclic lipopeptides (CLPs) including entolysin, lokisin, WLIP, putisolvin and xantholysin together with eight novel CLPs. In general, CLP types were linked to specific taxonomic groups within the fluorescent pseudomonads. Representative CLP‐producing bacteria showed effective control against CRRD while purified CLPs caused hyphal branching or hyphal leakage in P. myriotylum. The structure of cocoyamide A, a CLP which is predominantly produced by P. koreensis group isolates within the P. fluorescens complex is described. Compared with the white cocoyam, the red cocoyam rhizosphere appeared to support a more diverse CLP spectrum. It remains to be investigated whether this contributes to the field tolerance displayed by the red cocoyam.

Generalist predators potentially have access to a wide array of prey, but it is little studied how experience with specific prey affects preference for this prey. In particular, it is unknown how experience with pest prey affects predator foraging decisions in cases where the pest is nutritious but protected by a repelling, potentially deadly defence. We investigated preference of the soil predatory mite Gaeolaelaps aculeifer Canestrini for the risky pest springtail Protaphorura fimata Gisin relative to the safe non-pest springtail Folsomia candida Willem. Egg production under foraging on live or dead individuals of either prey showed that the two species had equal nutritional quality for G. aculeifer, but indicated that live F. candida were more difficult to catch than live P. fimata. Importantly, some G. aculeifer were killed by P. fimata defence secretions, demonstrating that live P. fimata are risky prey. Preference for P. fimata was generally high when mites were given a choice between a live individual of either prey, but this preference was reduced following exposure to live individuals of P. fimata. Furthermore, fewer G. aculeifer killed a prey and time until kill was longer after experience with live P. fimata. These findings indicate that live P. fimata induced a partial aversion on G. aculeifer during exposure. Our study shows that generalist predators can reduce their preference for risky prey following exposure. This indicates that generalist predators used in biological control against risky prey are most efficient against this prey if not exposed to it prior to release.

Agricultural practices often involve tank-mixing and co-application of insecticides with fungicides to control crop pests. However, natural methods relying on biological control agents such as hymenopteran parasitoids have been shown to be highly effective in suppressing crop pest populations. The current body of insecticide risk assessment data accounting for fungicide co-application is very small, the present study being the first to examine this in a parasitoid wasp. Through low-dose exposure to dry residues of the neonicotinoid insecticide thiacloprid, we examined its mortal and knockdown effect on Aphelinus abdominalis when co-applied with increasing doses of the fungicide tebuconazole. Both of these acute effects of thiacloprid were synergised (toxicity increased to a greater-than-additive effect) by tebuconazole, resulting in significant mortality from low-dose co-applications of tebuconazole, and significant knockdown even without co-applied tebuconazole, the effect increasing as tebuconazole concentration increased. We show the highly toxic effect that a low dose of thiacloprid imposes on A. abdominalis populations, and a synergistic toxicity when co-applied with low doses of tebuconazole. Our work suggests a need for updating pesticide risk assessment methods, accounting for pesticide mixtures, in order to make these risk assessments more field relevant.

Fusarium graminearum can cause Giberella Ear Rot (GER) and seedling blight in maize, resulting in major yield losses. Besides GER, the infected grains are consequently contaminated with multiple mycotoxins of F. graminearum. Zearalenone and trichothecenes, such as deoxynivalenol and its acetylated forms, are among the major mycotoxins associated with F. graminearum infection in maize. In the current work, we explored the effect of the endophytic fungal genera of Epicoccum and Sordaria, to control F. graminearum infection in comparative trials with Piriformospora spp., an elusive endophytic genus. Furthermore, we investigated the effect of these endophytes on zearalenone, deoxynivalenol, and 15-acetyldeoxynivalenol levels using in vitro and in planta assays. As plants are endowed with several detoxification mechanisms comprising e.g., glucosylation of trichothecenes, the effect of the isolated fungal endophytes on the deoxynivalenol-3-glucoside level was also assessed. In general, results showed a considerable variability in the antifungal activity, both among species and among isolates within one species. Additionally, the effect on mycotoxin levels was variable, and not necessarily related to the antifungal activity except for zearalenone levels which were consistently reduced by the endophytes. These results highlight the great potential of certain endophytic fungal strains as new biocontrol agents in agricultural science.

Powdery mildew (Blumeria graminis f.sp. tritici, f.sp. hordei, f.sp. avenae) is an important disease in cereal crops causing significant yield reductions, if not effectively controlled. The biofungicide Bacillus amyloliquefaciens (former subtilis) strain QST 713 suspension concentrate (Serenade®ASO) was investigated for its potential as a control agent against powdery mildew in winter wheat, spring barley, oats and triticale. Serenade®ASO reduced the severity of powdery mildew, providing moderate control in the range of 20–65%. The efficacy was highest at the earlier assessments and less pronounced at later assessments. With a few exceptions, no clear dose-response was seen between using 1, 2, 4, 6 or 8 L/ha Serenade®ASO applied four times at 8–10-day intervals. The efficacy was more variable compared with chemical references. Yield responses were positive following treatments. However, the yield increase by Serenade®ASO was insignificant and significantly inferior to that of prothioconazole. In a few cases, the use of Serenade®ASO in combination with the adjuvant Silwet®Gold improved the efficacy, but the results were inconsistent. The preventive and curative application of Serenade®ASO was tested at three dose rates in an artificially inoculated wheat and barley greenhouse pot trial. These trials confirmed the lack of a clear dose-response but confirmed that timing has a major impact on control, with the best control obtained when application took place on the day of inoculation in wheat and 0–2 days after inoculation in barley. This study revealed that powdery mildew challenges Serenade®ASO as a stand-alone control measure. The results show that further research is needed for the promotion of biofungicides as part of an integrated disease management approach in cereal diseases.

The relative importance of bottom‐up versus top‐down control of population dynamics has been the focus of much debate. In infectious disease biology, research is typically focused on the bottom‐up process of host resistance, wherein the direction of control flows from the lower to the higher trophic level to impact on pathogen population size and epidemiology. However, the importance of top‐down control by a pathogen's natural enemies has been mostly overlooked.Here, we explore the effects of, and interaction between, host genotype (i.e., genetic susceptibility to pathogen infection) and infection by a hyperparasitic fungus, Ampelomyces spp., on the establishment and early epidemic growth and transmission of a powdery mildew plant pathogen (Podosphaera plantaginis). We used a semi‐natural field experiment to contrast the impacts of hyperparasite infection, host‐plant resistance and spatial structure to reveal the key factors that determine pathogen spread. We then used a laboratory‐based inoculation approach to test whether the field experiment results hold across multiple pathogen–host genetic combinations and to explore hyperparasite effects on the pathogen's later life‐history stages.We found that hyperparasite infection had a negligible effect on within‐host infection development and between‐host spread of the pathogen during the onset of epidemics. In contrast, host‐plant resistance was the major determinant of whether plants became infected, and host genotype and proximity to an infection source determined infection severity.Our laboratory study showed that, while the interaction between host and pathogen genotypes was the key determinant of infection outcome, hyperparasitism did, on average, reduce the severity of infection. Moreover, hyperparasite infection negatively influenced the production of the pathogen's overwintering structures. Synthesis and applications. Our results suggest that bottom‐up host resistance affects pathogen spread, but top‐down control of powdery mildew pathogens is likely more effective against later life‐history stages. Further, while hyperparasitism in this system can reduce early pathogen growth under stable laboratory conditions, this effect is not detectable in a semi‐natural environment. Considering the effects of hyperparasites at multiple points in pathogen's life history will be important when considering hyperparasite‐derived biocontrol measures in other natural and agricultural systems., Our results suggest that bottom‐up host resistance affects pathogen spread, but top‐down control of powdery mildew pathogens is likely more effective against later life‐history stages. Further, while hyperparasitism in this system can reduce early pathogen growth under stable laboratory conditions, this effect is not detectable in a semi‐natural environment. Considering the effects of hyperparasites at multiple points in pathogen's life history will be important when considering hyperparasite‐derived biocontrol measures in other natural and agricultural systems.

Peat based growing media are not ecologically sustainable and often fail to support biological control. Miscanthus straw was (1) tested to partially replace peat; and (2) pre-colonized with a Trichoderma strain to increase the biological control capacity of the growing media. In two strawberry pot trials (denoted as experiment I & II), extruded and non-extruded miscanthus straw, with or without pre-colonization with T. harzianum T22, was used to partially (20% v/v) replace peat. We tested the performance of each mixture by monitoring strawberry plant development, nutrient content in the leaves and growing media, sensitivity of the fruit to the fungal pathogen Botrytis cinerea, rhizosphere community and strawberry defense responses. N immobilization by miscanthus straw reduced strawberry growth and yield in experiment II but not in I. The pre-colonization of the straw with Trichoderma increased the post-harvest disease suppressiveness against B. cinerea and changed the rhizosphere fungal microbiome in both experiments. In addition, defense-related genes were induced in experiment II. The use of miscanthus straw in growing media will reduce the demand for peat and close resource loops. Successful pre-colonization of this straw with biological control fungi will optimize crop cultivation, requiring fewer pesticide applications, which will benefit the environment and human health.

Ectotherms respond to their thermal environments by physiological acclimation, which increases tolerance to thermal extremes and may increase field performance. However, acclimation often has costs, and increased performance in some traits may be associated with reduced performance in other traits due to trade-offs. We investigated effects of thermal acclimation on predation, reproduction, starvation tolerance, and locomotor activity in the predatory mite Gaeolaelaps aculeifer Canestrini at 10, 15, and 20 degrees C after seven days of exposure to either of the same three temperatures, following rearing at 20 degrees C. To test for effects of cold acclimation on cold tolerance, another set of mites were acclimated at each of the three temperatures over four days including an additional group at 5 degrees C, and survival was assayed following a 24 h exposure to -2 degrees C. Our results showed highest cold-and starvation tolerance but lowest predation and reproduction across test temperatures in mites acclimated to 10 degrees C. These relationships were intermediate after 15 degrees C acclimation and opposite after 20 degrees C acclimation. Locomotor activity was unaffected by acclimation temperature. Since predation and reproduction of G. aculeifer are lowered across temperatures after cold acclimation, we recommend keeping cultures at 20 degrees C without cold exposure until release in the field when used against heavy pest infestations. However, if using G. aculeifer to keep small infestations minimized, we recommend using cold acclimated mites that better tolerate low temperature and low prey availability. Such thermal and metabolic robustness could be advantageous if predatory control agents are introduced in agroecosystems in early spring to prevent establishment of pest populations.

The Asian weaver ant Oecophylla smaragdina is of importance to Southeast Asian livelihoods as a source of human food and animal feed and as biological control agent in tree crops including mango and citrus. The introduction of weaver ants in plantations requires the inclusion of the reproductive queen. We report on locating the gravid queen in a mature O. smaragdina colony in Laos. The queen tree could be identified by considering tree height and number of nests in the tree: no tree was taller and housed more nests than the queen tree. The queen nest was a small nest, located near the tree top and near the trunk, and with more workers patrolling its exterior than at other small nests in the queen tree. The queen nest can be highly inconspicuous in dense tree crowns. Queen nest identification was ascertained by tapping and shaking nests, supporting branches, or entire trees, which elicits queen evacuation with retinue.

Pink ear rot of maize caused by Fusarium verticillioides, Fusariumproliferatum and Fusariumgraminearum can lead to severe yield losses and contamination of grain with a range of mycotoxins. Maize stalks colonized by Fusarium spp. are the main primary inoculum source for Fusarium incited epidemics in maize or other susceptible crops grown in rotation. The colonization of individual maize stalks originating from fields in The Netherlands, Italy and Nigeria by Fusarium spp. was quantified using specific TaqMan-PCR assays. Highest values were found for F. graminearum and Fusariumavenaceum in Dutch samples, for F. graminearum and FUM producing species (F. verticillioides and F. proliferatum) in Italian samples and FUM producing Fusarium spp. in Nigerian samples. The increase in Fusarium spp. colonization under field conditions during a period of 3-6 months after harvest of the maize crops varied considerably between individual stalks. The fungal and bacterial diversity was analyzed for sub-sets of stalks with high versus low increase of Fusarium colonization. Bacterial taxonomic groups such as Bacillus, Curtobacterium, Erwinia, Flavobacterium, Novosphingobium, Pantoea, Sphingomonas, Rahnella and Staphylococcus and fungal taxonomic groups such as Acremomium sp., Cryptococcus flavescens, Cryptococcus zeae, Leptosphaeria sp. and Microdochium bolleyi were more abundant in the stalks with lower increase in pathogen colonization. Such fungal and bacterial groups associated with 'suppressive stalks' may be antagonistic to Fusarium spp. and a source of candidate strains for the selection of new biological control agents.

There is limited understanding about how insect movement patterns are influenced by landscape features, and how landscapes can be managed to suppress pest phytophage populations in crops. Theory suggests that the relative timing of pest and natural enemy arrival in crops may influence pest suppression. However, there is a lack of data to substantiate this claim. We investigate the movement patterns of insects from native vegetation (NV) and discuss the implications of these patterns for pest control services. Using bi-directional interception traps we quantified the number of insects crossing an NV/crop ecotone relative to a control crop/crop interface in two agricultural regions early in the growing season. We used these data to infer patterns of movement and net flux. At the community-level, insect movement patterns were influenced by ecotone in two out of three years by region combinations. At the functional-group level, pests and parasitoids showed similar movement patterns from NV very soon after crop emergence. However, movement across the control interface increased towards the end of the early-season sampling period. Predators consistently moved more often from NV into crops than vice versa, even after crop emergence. Not all species showed a significant response to ecotone, however when a response was detected, these species showed similar patterns between the two regions. Our results highlight the importance of NV for the recruitment of natural enemies for early season crop immigration that may be potentially important for pest suppression. However, NV was also associated with crop immigration by some pest species. Hence, NV offers both opportunities and risks for pest management. The development of targeted NV management may reduce the risk of crop immigration by pests, but not of natural enemies.

There is considerable evidence that both plant diversity and plant identity can influence the level of predation and predator abundance aboveground. However, how the level of predation in the soil and the abundance of predatory soil fauna are related to plant diversity and identity remains largely unknown. In a biodiversity field experiment, we examined the effects of plant diversity and identity on the infectivity of entomopathogenic nematodes (EPNs, Heterorhabditis and Steinernema spp.), which prey on soil arthropods, and abundance of carnivorous non-EPNs, which are predators of other nematode groups. To obtain a comprehensive view of the potential prey/food availability, we also quantified the abundance of soil insects and nonpredatory nematodes and the root biomass in the experimental plots. We used structural equation modeling (SEM) to investigate possible pathways by which plant diversity and identity may affect EPN infectivity and the abundance of carnivorous non-EPNs. Heterorhabditis spp. infectivity and the abundance of carnivorous non-EPNs were not directly related to plant diversity or the proportion of legumes, grasses and forbs in the plant community. However, Steinernema spp. infectivity was higher in monocultures of Festuca rubra and Trifolium pratense than in monocultures of the other six plant species. SEM revealed that legumes positively affected Steinernema infectivity, whereas plant diversity indirectly affected the infectivity of Heterorhabditis EPNs via effects on the abundance of soil insects. The abundance of prey (soil insects and root-feeding, bacterivorous, and fungivorous nematodes) increased with higher plant diversity. The abundance of prey nematodes was also positively affected by legumes. These plant community effects could not be explained by changes in root biomass. Our results show that plant diversity and identity effects on belowground biota (particularly soil nematode community) can differ between organisms that belong to the same feeding guild and that generalizations about plant diversity effects on soil organisms should be made with great caution.

Plant-associated bacteria are known for their high functional trait diversity, from which many are likely to play a role in primary and secondary succession, facilitating plant establishment in suboptimal soils conditions. Here we used an undisturbed salt marsh chronosequence that represents over 100 years of soil development to assess how the functional traits of plant associated bacteria respond to soil type, plant species and plant compartment. We isolated and characterized 808 bacterial colonies from the rhizosphere soil and root endosphere of two salt marsh plants, Limonium vulgare and Artemisia maritima, along the chronosequence. From these, a set of 59 strains (with unique BOX-PCR patterns, 16S rRNA sequence and unique to one of the treatments) were further screened for their plant growth promoting traits (siderophore production, IAA production, exoprotease production and biofilm formation), traits associated with bacterial fitness (antibiotic and abiotic stress resistance - pH, osmotic and oxidative stress, and salinity) and metabolic potential. An overall view of functional diversity (multivariate analysis) indicated that the distributional pattern of bacterial functional traits was driven by soil type. Samples from the late succession (Stage 105 year) showed the most restricted distribution, harboring strains with relatively low functionalities, whereas the isolates from intermediate stage (35 year) showed a broad functional profiles. However, strains with high trait performance were largely from stage 65 year. Grouping the traits according to category revealed that the functionality of plant endophytes did not vary along the succession, thus being driven by plant rather than soil type. In opposition, the functionality of rhizosphere isolates responded strongly to variations in soil type as observed for antibiotic resistance (P = 0.014). Specifically, certain Pseudomonas sp. and Serratia sp. strains revealed high resistance against abiotic stress and antibiotics and produce more siderophores, confirming the high plant-growth promoting activity of these two genera. Overall, this study contributes to a better understanding of the functional diversity and adaptation of the microbiome at typical salt marsh plant species across soil types. Specifically, soil type was influential only in the rhizosphere but not on the endosphere, indicating a strong plant-driven effect on the functionality of endophytes.

Tracking of fluorescent protein (FP)-labelled rhizobacteria is a key prerequisite to gain insights into plant-bacteria interaction mechanisms. However, the performance of FPs mostly has to be optimized for the bacterial host and for the environment of intended application. We report on the construction of mutational libraries of the superfolder green fluorescent protein sfGFP and the red fluorescent protein mKate2 in the bacterium B. mycoides, which next to its potential as plant-biocontrol agent occasionally enters an endophytic lifestyle. By fluorescence-activated cell sorting and comparison of signal intensities at the colony and single-cell level, the variants sfGFP(SPS6) and mKate (KPS12) with significantly increased brightness were isolated. Their high applicability for plant-bacteria interaction studies was shown by confocal laser scanning microscopy tracking of FP-tagged B. mycoides strains after inoculation to Chinese cabbage plants in a hydroponic system. During the process of colonization, strain EC18 rapidly attached to plant roots and formed a multicellular matrix, especially at the branching regions of the root hair, which probably constitute entrance sites to establish an endophytic lifestyle. The universal applicability of the novels FPs was proven by expression from a weak promoter, dual-labelling of B. mycoides, and by excellent expression and detectability in additional soil- and rhizosphere-associated Bacillus species.

The mutualistic relationship that the garden ant Lasius niger (L.) establishes with trophobiotic homopterans makes this ant an unwelcome host in commercial crops, as ants improve the survival of homopteran pests from which they collect honeydew as a source of carbohydrates. Because the offering of alternative sugar sources can be used to disrupt this relationship, the present study explored L. niger's preference towards sugar and amino acid components that may be used in sugar solutions to increase their attractiveness. We tested the ant's preference between basic sugars (mono- and disaccharides) used as main ingredients and attractants (trisaccharides and amino acid (AA) sources) added to basic sugar in small amounts. Results showed that ants preferred disaccharides over monosaccharides, and that trisaccharides increased the attractiveness of sucrose solutions, albeit not when a protein source was added to the mix. In the case of AA sources, ants preferred components with a more diverse composition. In conclusion, trisaccharides and AA sources can be used to increase the attractiveness of sugar solutions, leading to the development of solutions that when supplied in artificial feeders can out-compete honeydew and disrupt harmful ant-homopteran mutualisms in agriculture.

This study was conducted to determine whether various food resources enhanced the longevity and fecundity of the egg parasitoid Trichogramma brassicae Bezdenko, 1968 (Hymenoptera: Trichogrammatidae) under laboratory conditions (25°C, 65% RH, 16L:8D h photoperiod) at Laboratory of Biological Control, Department of Plant Protection, Agriculture Faculty, Namık Kemal University in 2014. Newly hatched female wasps were fed on Ephestia kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) eggs with either honey, grape molasses and royal jelly as a main food, alone or double combination of this main foods or supplemented with resin (derived from plants), acacia nectar, Paulownia nectar, red tulip nectar, yellow asphodel nectar, apple syrup, liquid of E. kuehniella eggs or mashed E. kuehniella larvae. Trichogramma brassicae, females that were fed on honey and acacia nectar (17.47 d), honey + apple syrup (17.20 d), honey (16.93 d) and honey + Paulownia nectar (16.60 d) lived significantly longer than females that fed on other floral nectars and artificial diets. Females were fed on royal jelly + mashed E. kuehniella larvae (1.40 d) had the shortest longevity. Trichogramma brassicae females that were fed on honey (106.8 eggs), honey + acacia nectar (105.4 eggs), Paulownia nectar (103.13 eggs) parasitized significantly more hosts than females that fed on other floral nectars and artificial diets. Females fed on royal jelly were had the lowest parasitizing ability (3.33 eggs). These results showed that providing T. brassicae with honey, honey + acacia nectar, honey + apple syrup resulted in greater longevity and total fecundity than other food resources., Bu çalışma, çeşitli besin kaynaklarının yumurta parazitoiti Trichogramma brassicae Bezdenko, 1968 (Hymenoptera: Trichogrammatidae)’e etkilerinin araştırılması amacıyla Namık Kemal Üniversitesi, Ziraat Fakültesi, Bitki Koruma Bölümü, Biyolojik Mücadele Laboratuvarı’nda laboratuvar koşullarında (25°C sıcaklık, %65 nem, 16:8 saat (aydınlık: karanlık) aydınlanma periyodu) 2014 yılında yürütülmüştür. Ergin dişi bireyler, değirmen güvesi Ephestia kuehniella Zeller, 1879 (Lepidoptera: Pyralidae) yumurtaları üzerinde ana besin (bal, üzüm pekmezi ve arı sütü) ve ara besin (reçine (bitkilerden salgılanan), akasya nektarı, çin kavağı nektarı, kırmızı lale nektarı, sarızambak nektarı, elma şurubu, E. kuehniella yumurta sıvısı ve ezilmiş E. kuehniella larvası) ve bu ana besinlerin ikili kombinasyonları ile beslenmiştir. Bal + akasya nektarı (17.47 gün), bal + elma şurubu (17.20 gün), bal + çin kavağı nektarı (16.60 gün) ile beslenen bireylerin diğer besin ve nektar ile beslenen bireylere göre daha uzun yaşadığı belirlenmiştir. En kısa ömür ise arı sütü + ezilmiş E. kuehniella larvası (1.40 gün) ile beslenen bireylerde görülmüştür. Çalışma sonucunda toplam parazitlenen yumurta sayısı, bal (106.8 yumurta), bal + akasya nektarı (105.4 yumurta), çin kavağı nektarı (103.13 yumurta) ile beslenen bireylerde ve belirgin olarak diğer besin ile beslenen bireylerin parazitledikleri yumurta sayılarından fazla bulunmuştur. Arı sütü ile beslenen bireylerin parazitledikleri yumurta sayısı (3.33 yumurta) en düşük olarak belirlenmiştir. Bu sonuçlar, T. brassicae'ye bal, bal + akasya nektarı, bal + elma şurubu verilmesinin diğer gıda kaynaklarına göre daha uzun ömür ve toplam doğurganlık sağladığını göstermiştir.

Immobilized preys are routinely used in agro-ecological exposure studies to quantify predation of pests under field conditions, but this method has not been validated. Our purpose was to determine the validity of using immobilized adults of the major rice pest Nilaparvata lugens, brown plant hopper (BPH), as sentinels. We used direct observation by video recording to determine the causal agents of removal of field exposed BPH sentinels with two experiments: 1) we recorded removal events of dead, immobilized BPH; and 2) we compared removal of (i) dead, immobilized BPH, (ii) live, immobilized BPH, and (iii) live, mobile BPH. Long-horned grasshoppers were responsible for most removals of dead, immobilized BPH, in both experiments. Predatory ground beetles removed most of the live, immobilized BPH, whereas frogs were the major predators of live, mobile BPH. Overall, we showed that removal of immobilized sentinel prey is not representative for predation of live, mobile prey, stressing the need for a critical assessment of commonly used sentinel methods. In addition, we found that frogs played the major role in predation of BPH in rice. As current strategies to enhance biocontrol of planthoppers in rice focus on arthropod natural enemies, this finding could have major implications.

Chitin and its derivatives are natural biopolymers that are often used as compounds for the control of soilborne plant pathogens. In spite of recent advances in agricultural practices involving chitin amendments, the microbial communities in chitin-amended soils remain poorly known. The objectives of this study were (1) to investigate the bacterial diversity and abundance in an agricultural soil supplemented with chitin that turned disease-suppressive and (2) to assess the emergence of chitinolytic bacteria under conditions of raised soil pH. Amplicon pyrosequencing of soil-extracted DNA based on the 168 rRNA genes was used to characterize the structures of bacterial communities in soil, chitin-amended or not, with native versus raised pH (5.7 vs 8.7), in microcosms and the field. As a result of chitin addition, changes in the relative abundances of Actinobacteria, Proteobacteria and Bacteroidetes were observed in the field soil. A large and significant increase of the relative abundance of Oxalobacteraceae (Betaproteobacteria, Burkholderiales) was found. Within the Oxalobacteraceae, the genera Duganella and Massilia showed large increases. Moreover, responses of the Alpha- and Gammaproteobacteria appeared shortly after the alteration of the soil pH in the microcosms. A significant decrease in the abundance of Actinobacteria was observed in the chitin-amended field soil and in the microcosm at high pH. Overall, the bacterial abundance in soil tended to decrease with the addition of chitin. Two groups, Actinobacteria and Oxalobacteraceae, were found to be most responsive to the amendment. These results enhance the understanding of responses to chitin and possible interactions within bacterial communities in soil that can be correlated to soil disease suppressiveness. (C) 2014 Elsevier Ltd. All rights reserved.