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BROWN marmorated stink bug, PREDATION, HEMIPTERA, STINKBUGS, PARASITISM, and LAURACEAE

The invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a polyphagous pest that disperses from non-crop host plants into crops in search of food. Sassafras trees (Sassafras albidum (Nutt.) Nees; Lauraceae) are found commonly in woodland habitats in the southeastern US and may therefore be a potential host. The main objective of this 2-yr study was to determine if sassafras serves as a host plant for this pest in woodland habitats adjacent to crops in Prattville, Alabama, and Byron, Georgia, USA. Each yr pheromone-baited traps were deployed in the canopy of sassafras trees to capture H. halys. We also evaluated parasitism and predation of H. halys sentinel egg masses by native parasitoids and predators in sassafras. Halyomorpha halys adult males and females as well as second through fifth instars were captured in traps and observed in sassafras trees over the season at both locations each yr of the study. Trissolcus euschisti Ashmead (Hymenoptera: Scelionidae) (67.7%) and Anastatus reduvii (Howard) (Hymenoptera: Eupelmidae) (18.3%) were the primary parasitoid species that emerged from H. halys sentinel egg masses. Stylet sucking (62.3%) and chewing (32.0%) were the primary types of predation on H. halys eggs. We conclude that sassafras is a reproductive host plant for H. halys, and native natural enemies prey on and parasitize H. halys egg masses in this host plant. La chinche hedionda invasora marrón marmolada, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), es una plaga polífaga que se dispersa de plantas hospedantes no cultivadas a los cultivos en busca de alimento. Se les encuentran en los árboles de sasafrás (Sassafras albidum [Nutt.] Nees; Lauraceae) comúnmente en hábitats boscosos del sureste de los EE. UU. y por lo tanto este puede ser un hospedero potencial. El objetivo principal de este estudio de 2 años fue determinar si el sasafrás sirve como planta hospedera para esta plaga en hábitats boscosos adyacentes a cultivos en Prattville, Alabama, y Byron, Georgia, EE. UU. Cada año, se colocaron trampas cebadas con feromonas en el dosel de los árboles de sasafrás para capturar H. halys. También evaluamos el parasitismo y la depredación de masas de huevos centinela de H. halys por parasitoides nativos y depredadores en sasafrás. Se capturaron machos y hembras adultos así como ninfas del segundo al quinto estadio de Halyomorpha halys en las trampas, y se observaron en árboles de sasafrás durante la temporada en ambos lugares cada año del estudio. Trissolcus euschisti Ashmead (Hymenoptera: Scelionidae) (67,7%) y Anastatus reduvii (Howard) (Hymenoptera: Eupelmidae) (18,3%) fueron las principales especies de parasitoides que emergieron de las masas de huevos centinela de H. halys. La succión por los estiletes (62,3%) y la masticación (32,0%) fueron las principales clases de depredación sobre los huevos de H. halys. Concluimos que el sasafrás es una planta hospedera reproductiva para H. halys, y los enemigos naturales nativos se alimentan y parasitan las masas de huevos de H. halys en esta planta hospedera. [ABSTRACT FROM AUTHOR]

BROWN marmorated stink bug, STINKBUGS, PARASITISM, PREDATION, and HEMIPTERA

Stink bugs, including Halyomorpha halys (Stål) and Nezara viridula (L.), are agricultural pests that feed on fruit in a variety of crops. Monitoring predation and parasitism of stink bug egg masses furthers our understanding of potential biological control tactics. However, best practices for laboratory and field assessments of parasitism and predation of egg masses require further attention. We carried out a series of laboratory and field experiments to test whether parasitism and predation for three types of sentinel H. halys egg masses, fresh, frozen, and refrigerated, varied in agricultural commodities. In addition, we asked if predation and parasitism differed between sentinel and naturally occurring H. halys and N. viridula egg masses in soybean. In the laboratory, more H. halys eggs were parasitized by Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) if they were frozen or refrigerated compared to fresh eggs. Similarly, in the field, parasitism was higher for frozen egg masses than fresh. In 2018 and 2019, H. halys natural egg masses had higher parasitism and lower predation compared to sentinel egg masses in soybean. In a paired field test during 2020 and 2021, there was no difference in parasitism between H. halys natural and sentinel eggs, but much higher incidence of parasitism was detected in natural N. viridula egg masses than sentinel eggs. Collecting natural egg masses is the best methodology for field assessment of parasitism of stink bug egg masses; however, if natural egg masses are not easily available, deploying refrigerated sentinel egg masses is a good alternative. [ABSTRACT FROM AUTHOR]

MISSENSE mutation, GENETIC variation, LIGAND-gated ion channels, NEUROTRANSMITTER receptors, AMPA receptors, and NEURAL development

GRIA1 encodes the GluA1 subunit of α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors, which are ligand-gated ion channels that act as excitatory receptors for the neurotransmitter L -glutamate (Glu). AMPA receptors (AMPARs) are homo- or heteromeric protein complexes with four subunits, each encoded by different genes, GRIA1 to GRIA4. Although GluA1-containing AMPARs have a crucial role in brain function, the human phenotype associated with deleterious GRIA1 sequence variants has not been established. Subjects with de novo missense and nonsense GRIA1 variants were identified through international collaboration. Detailed phenotypic and genetic assessments of the subjects were carried out and the pathogenicity of the variants was evaluated in vitro to characterize changes in AMPAR function and expression. In addition, two Xenopus gria1 CRISPR-Cas9 F 0 models were established to characterize the in vivo consequences. Seven unrelated individuals with rare GRIA1 variants were identified. One individual carried a homozygous nonsense variant (p.Arg377Ter), and six had heterozygous missense variations (p.Arg345Gln, p.Ala636Thr, p.Ile627Thr, and p.Gly745Asp), of which the p.Ala636Thr variant was recurrent in three individuals. The cohort revealed subjects to have a recurrent neurodevelopmental disorder mostly affecting cognition and speech. Functional evaluation of major GluA1-containing AMPAR subtypes carrying the GRIA1 variant mutations showed that three of the four missense variants profoundly perturb receptor function. The homozygous stop-gain variant completely destroys the expression of GluA1-containing AMPARs. The Xenopus gria1 models show transient motor deficits, an intermittent seizure phenotype, and a significant impairment to working memory in mutants. These data support a developmental disorder caused by both heterozygous and homozygous variants in GRIA1 affecting AMPAR function. [ABSTRACT FROM AUTHOR]

STINKBUGS, BROWN marmorated stink bug, HYMENOPTERA, OVIPARITY, BIOLOGICAL pest control agents, GREENBUG, and HOSTS of parasitoids

• We tested the physiological host ranges of an introduced biocontrol agent (T. basalis) and native parasitoid (T. oenone). • T. basalis attacks and develops in all nine pentatomid taxa we tested. • The native T. oenone attacks and develops in seven out of eight pentatomid species we tested. • Parasitism efficiencies were high for all treatments (>60%). Retrospective host range testing is essential for understanding the physiological host range of introduced biological control agents (BCAs) and updating forecasts of non-target risks. It is especially important to conduct this work if there was no host range testing prior to release of the agent. Trissolcus basalis Wollaston was released in New Zealand in 1949 against green vegetable bug (Nezara viridula [L.]), but host range testing was never undertaken, and subsequent work in the 1960s was only of a qualitative nature and remains incomplete. The host-parasitoid complex between New Zealand pentatomids, T. basalis , and the native pentatomid parasitoid Trissolcus oenone Dodd, is therefore poorly understood. We conducted no-choice oviposition tests between the two resident Trissolcus species and all available New Zealand pentatomid species to characterise the physiological (=fundamental) host ranges of these parasitoids. We present the results of the first retrospective host-specificity study on T. basalis in New Zealand. Our results show T. basalis attacks and develops in all nine pentatomid taxa we exposed it to (including the endemic alpine species Hypsithocus hudsonae Bergroth), while T. oenone attacks and develops in seven out of eight pentatomid species we tested it against (and its capacity to attack H. hudsonae remains unknown). Parasitism efficiencies for all treatments exceeded 60%, while development times were similar for both parasitoids regardless of host. We discuss the importance of physiological host range testing for understanding potential non-target effects. Trissolcus japonicus Ashmead (Hymenoptera: Scelionidae) was recently approved for release in New Zealand against brown marmorated stink bug Halyomorpha halys Stål (Hemiptera: Pentatomidae), subject to its potential establishment, and we examine our results in the context of potential competition between introduced parasitoids for non-target species. [ABSTRACT FROM AUTHOR]

MEDICAL personnel, BLOOD testing, COVID-19 testing, SICK leave, and HOSPITALS

Background: COVID-19 is an ongoing pandemic leading to exhaustion of the hospital care system. Our health care system has to deal with a high level of sick leave of health care workers (HCWs) with COVID-19 related complaints, in whom an infection with SARS-CoV-2 has to be ruled out before they can return back to work. The aim of the present study is to investigate if the recently described CoLab-algorithm can be used to exclude COVID-19 in a screening setting of HCWs. Methods: In the period from January 2021 till March 2021, HCWs with COVID-19-related complaints were prospectively collected and included in this study. Next to the routinely performed SARS-CoV-2 RT-PCR, using a set of naso- and oropharyngeal swab samples, two blood tubes (one EDTA- and one heparin-tube) were drawn for analysing the 10 laboratory parameters required for running the CoLab-algorithm. Results: In total, 726 HCWs with a complete CoLab-laboratory panel were included in this study. In this group, 684 HCWs were tested SARS-CoV-2 RT-PCR negative and 42 cases RT-PCR positive. ROC curve analysis showed an area under the curve (AUC) of 0.853 (95% CI: 0.801–0.904). At a safe cut-off value for excluding COVID-19 of -6.525, the sensitivity was 100% with a specificity of 34% (95% CI: 21 to 49%). No SARS-CoV-2 RT-PCR cases were missed with this cut-off and COVID-19 could be safely ruled out in more than one third of HCWs. Conclusion: The CoLab-score is an easy and reliable algorithm that can be used for screening HCWs with COVID-19 related complaints. A major advantage of this approach is that the results of the score are available within 1 hour after collecting the samples. This results in a faster return to labour process of a large part of the COVID-19 negative HCWs (34%), next to a reduction in RT-PCR tests (reagents and labour costs) that can be saved. [ABSTRACT FROM AUTHOR]

STINKBUGS, OLIVE fly, OLIVE, FRUIT development, BROWN marmorated stink bug, INTRODUCED organisms, and LEAFHOPPERS

Olives, Olea europaea L. (Oleaceae), are an emerging commercial crop in Florida; however, potential arthropod threats during olive tree establishment and fruit development remain uncharacterized. Two potential pests that may threaten olive fruit production directly are native and invasive pentatomid stink bugs, which are important pest species of many crops in the southeast, and the invasive olive fruit fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae),which is not known to be established in Florida. Monitoring for stink bugs during fruit maturation was done using dual funnel tube traps baited with stink bug lures. Yellow sticky card traps baited with food and pheromone lures were used to monitor for the olive fruit fly. Both trap types were placed in tree canopies in 4 North Central Florida olive groves during the anticipated fruit development period for 2 growing seasons. Whereas neither of the invasive species targeted (Halyomorpha halys Stål [Hemiptera: Pentatomidae] or B. oleae) were detected, several other potential pests were identified including brown stink bugs (Euschistus spp.; Hemiptera: Pentatomidae), glassy winged sharpshooters, Homalodisca vitripennis Germar (Hemiptera: Cicadellidae), and grasshoppers. No fruit damage attributable to arthropod pests was detected although fruit production was very low with limited samples. These results contribute to awareness of potential pests that may jeopardize olive fruit production and aid in the future studies to develop effective monitoring activities for Florida growers. [ABSTRACT FROM AUTHOR]

STINKBUGS, BROWN marmorated stink bug, CYTOCHROME oxidase, GENETIC variation, and HEMIPTERA

The arrival, establishment and pest status of Halyomorpha halys in Europe and non-native countries in Asia have been well-documented, with thorough characterisation of the genetic diversity and occurrence of cytochrome oxidase I (COI) haplotypes in Switzerland, France, Hungary, Italy and Greece. However, a number of gaps exist in terms of the characterisation of the haplotype diversity and occurrence of H. halys along the invasion front that covers eastern Europe, western and central Asia. To contribute towards filling this gap, the COI haplotype diversity and distribution were investigated for H. halys collected in Serbia, Ukraine, Russia, Georgia and Kazakhstan. A total of 646 specimens were analysed and five haplotypes were found (H1, H3, H8, H33 and H80). Haplotype H1 was present in all five countries investigated and was the only haplotype detected amongst > 500 specimens collected from Ukraine, Russia and Georgia. H1 (82%) was the dominant haplotype found in Kazakhstan, alongside H3 (18%). In contrast to the low or no diversity observed in these four countries, Serbia had higher haplotype diversity and was represented by five haplotypes. Although H3 was dominant (47%) in Serbia, H1 was also prevalent (40%); the remaining haplotypes (H8, H33 and H80) were minor contributors (1-11%) to the haplotype composition. The results are discussed in context with other known populations in neighbouring countries and patterns of haplotype diversity indicate the movement of successful invasive populations in Europe to generate secondary invasions along the eastern front of the invasion in Eurasia. Possible scenarios regarding the spread of particular haplotypes in these regions are discussed, along with suggestions for future research to fill existing gaps. [ABSTRACT FROM AUTHOR]

BROWN marmorated stink bug, PREDATORY insects, ORCHARDS, ANTS, HYMENOPTERA, and PREDATORY animals

In recent years, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae, Cappaeini) has become an invasive pest in North America and Europe, where it caused extensive damage to agriculture, resulting in great economic losses. Evaluating the potential of native predators in the invaded areas, ants might represent good candidates thanks to their biology, ecology, and behavior. In Italy, H. halys proved to be the top key pest in pear orchards, where the black garden ant, Lasius niger (L.) (Hymenoptera: Formicidae, Lasiini), is the most abundant ant species. The aim of this study was to evaluate the predatory ability of L. niger on the eggs and on all the juvenile instars of H. halys under laboratory conditions. The results indicate that L. niger significantly reduces the survival of the second and third nymphal instars by 56 and 58%, respectively, but it is unable to reduce the egg hatching and the survival of the first, fourth, and fifth instars. Our preliminary results obtained in laboratory conditions suggest a possible role of the ant L. niger in controlling H. halys invasion mainly acting on the smaller and more mobile nymphal stages. The effective role of this species as potential biocontrol agents of H. halys in fruit orchards in association with other ant species as well as with other predatory insects is discussed. [ABSTRACT FROM AUTHOR]

STINKBUGS, BROWN marmorated stink bug, CYTOCHROME oxidase, GENETIC variation, and HEMIPTERA

The arrival, establishment and pest status of Halyomorpha halys in Europe and non-native countries in Asia have been well-documented, with thorough characterisation of the genetic diversity and occurrence of cytochrome oxidase I (COI) haplotypes in Switzerland, France, Hungary, Italy and Greece. However, a number of gaps exist in terms of the characterisation of the haplotype diversity and occurrence of H. halys along the invasion front that covers eastern Europe, western and central Asia. To contribute towards filling this gap, the COI haplotype diversity and distribution were investigated for H. halys collected in Serbia, Ukraine, Russia, Georgia and Kazakhstan. A total of 646 specimens were analysed and five haplotypes were found (H1, H3, H8, H33 and H80). Haplotype H1 was present in all five countries investigated and was the only haplotype detected amongst > 500 specimens collected from Ukraine, Russia and Georgia. H1 (82%) was the dominant haplotype found in Kazakhstan, alongside H3 (18%). In contrast to the low or no diversity observed in these four countries, Serbia had higher haplotype diversity and was represented by five haplotypes. Although H3 was dominant (47%) in Serbia, H1 was also prevalent (40%); the remaining haplotypes (H8, H33 and H80) were minor contributors (1-11%) to the haplotype composition. The results are discussed in context with other known populations in neighbouring countries and patterns of haplotype diversity indicate the movement of successful invasive populations in Europe to generate secondary invasions along the eastern front of the invasion in Eurasia. Possible scenarios regarding the spread of particular haplotypes in these regions are discussed, along with suggestions for future research to fill existing gaps. [ABSTRACT FROM AUTHOR]

STINKBUGS, BROWN marmorated stink bug, BIOLOGICAL control of insects, HEMIPTERA, BIOLOGICAL pest control agents, BIOLOGICAL pest control, and INTEGRATED pest control

Invasive stink bugs (Hemiptera: Pentatomidae) are responsible for high economic losses to agriculture on a global scale. The most important species, dating from recent to old invasions, include Bagrada hilaris (Burmeister), Halyomorpha halys (Stål), Piezodorus guildinii (Westwood), Nezara viridula (L.), and Murgantia histrionica (Hahn). Bagrada hilaris, H. halys, and N. viridula are now almost globally distributed. Biological control of these pests faces a complex set of challenges that must be addressed to maintain pest populations below the economic injury level. Several case studies of classical and conservation biological control of invasive stink bugs are reported here. The most common parasitoids in their geographical area of origin are egg parasitoids (Hymenoptera: Scelionidae, Encyrtidae, and Eupelmidae). Additionally, native parasitoids of adult stink bugs (Diptera: Tachinidae) have in some cases adapted to the novel hosts in the invaded area and native predators are known to prey on the various instars. Improving the efficacy of biocontrol agents is possible through conservation biological control techniques and exploitation of their chemical ecology. Moreover, integration of biological control with other techniques, such as behavioural manipulation of adult stink bugs and plant resistance, may be a sustainable pest control method within organic farming and integrated pest management programs. However, additional field studies are needed to verify the efficacy of these novel methods and transfer them from research to application. [ABSTRACT FROM AUTHOR]

BIOLOGICAL weed control, BIOLOGICAL pest control agents, CHRYSOMELIDAE, BEETLES, HYMENOPTERA, and EUCALYPTUS

The solitary larval endoparasitoid Eadya daenerys Ridenbaugh (Hymenoptera: Braconidae) is a proposed biocontrol agent of Paropsis charybdis Stål (Coleoptera: Chrysomelidae, Chrysomelinae), a pest of eucalypts in New Zealand. Eadya daenerys oviposition behaviour was examined in two assay types during host range testing, with the aim of improving ecological host range prediction. No‐choice sequential and two‐choice behavioural observations were undertaken against nine closely related species of New Zealand non‐target beetle larvae, including a native beetle, introduced weed biocontrol agents, and invasive paropsine beetles. No behavioural measure was significantly different between no‐choice and two‐choice tests. In sequential no‐choice assays the order of first presentation (target–non‐target) had no significant effect on the median number of attacks or the attack rate while on the plant. Beetle species was the most important factor. Parasitoids expressed significantly lower on‐plant attack rates against non‐targets compared to target P. charybdis larvae. The median number of attacks was always higher towards target larvae than towards non‐target larvae, except for the phylogenetically closest related non‐target Trachymela sloanei (Blackburn) (Coleoptera: Chrysomelidae, Chrysomelinae). Most non‐target larvae were disregarded upon contact, which suggests that the infrequent attack behaviour observed by two individual E. daenerys against Allocharis nr. tarsalis larvae in two‐choice tests and the frass of Chrysolina abchasica (Weise) was probably abnormal host selection behaviour. Results indicate that E. daenerys is unlikely to attack non‐target species apart from Eucalyptus‐feeding invasive paropsines (Chrysomelinae). Non‐lethal negative impacts upon less preferred non‐target larvae are possible if E. daenerys does attack them in the field; however, this is likely to be rare. [ABSTRACT FROM AUTHOR]

HYMENOPTERA, CURCULIONIDAE, HOMOPTERA, PEST control, INSECT collection & preservation, BEETLES, and HEMIPTERA

The knowledge of the entomological fauna in productive systems is important for the agroecological management since beneficial insects are a key resource for pest management in horticultural systems. Scientific information on the biodiversity present in a given area is essential as well as the ecological function and/or feeding habits of the insects. In Alto Valle de Río Negro and Neuquén, horticultural production systems can be described as highly dependent on chemical inputs for pest management and fertilization. The aim of this study is to carry out an inventory of the biodiversity of some families of Hemiptera, Coleoptera (Curculionidae) and Hymenoptera present in peri-urban and rural farms located in Neuquén and Río Negro, respectively. Insects were collected through pitfall and sweeping net on tomato and pepper crops and the surrounding non-cultivated areas. Idiosystatus Berg (Auchenorrhyncha) was cited for the first time from Argentina. Species cited for the first time from Neuquén: Hemiptera: Auchenorrhyncha: Acanalonia chloris (Berg), Syncharina punctatissima (Signoret), Amplicephalus dubius Linnavuori, Exitianus obscurinervis (Stål), Agalliana ensigera Oman and Bergallia signata (Stål); Hemiptera: Heteroptera: Harmostes (Harmostes) prolixus Stål and Atrachelus (Atrachelus) cinereus (Fabricius); Coleoptera: Curculionidae: Hypurus bertrandi (Perris), Naupactus leucoloma Boheman, Otiorhynchus rugosostriatus (Goeze) and Sitona discoideus Gyllenhal and Hymenoptera: Xylocopa (Neoxylocopa) augusti Lepeletier and Pseudagapostemon (Neagapostemon) singularis Jörgensen. Species cited for the first time from Río Negro: Hemiptera: Auchenorrhyncha: Amplicephalus dubius Linnavuori, Amplicephalus marginellanus Linnavuori, Circulifer tenellus (Baker) and Xerophloea viridis (Fabricius); Hemiptera: Heteroptera: Tupiocoris cucurbitaceus (Spinola), Atrachelus (Atrachelus) cinereus (Fabricius), Dichelops furcatus (Fabricius) and Harmostes (Harmostes) prolixus Stål; Coleptera: Curculionidae: Naupactus xanthographus (Germar) and Hymenoptera: Diadasia pereyrae (Holmberg) and Dialictus autranellus (Vachal). [ABSTRACT FROM AUTHOR]

TAMARISKS, ASSASSIN bugs, LIFE history theory, PREDATORY animals, BODY size, and NATURAL history

The harpactorine assassin bug, Zelus tetracanthus (Stål) (Hemiptera: Reduviidae), is an insect predator frequently found in surveys of saltcedar (Tamarix spp.) in Oklahoma. Previous studies in a laboratory showed it could prey on Diorhabda carinulata (Desbrochers) (Coleoptera: Chrysomelidae), a recently introduced biological control agent for Tamarix. An F2 cohort of Z. tetracanthus was reared from egg to adult to measure stage-specific development rates and describe immature stages at 22 ± 1.0°C and 16:8 light:dark hours. The mean times for development of the five instars were 6.96 ± 0.13, 5.18 ± 0.13, 6.94 ± 0.29, 10.92 ± 0.43, and 17.93 ± 0.76 days, respectively. Several anatomical characters to distinguish instars, including body size, body color, and select morphological characters were described. Data from museum collections of Z. tetracanthus suggested the insect has a univoltine life cycle. The development data contrast with a previous description of Z. socius (= Z. tetracanthus) and illustrate the need to further study the variable morphology, natural history, and genetic makeup of the species. [ABSTRACT FROM AUTHOR]

BIOLOGICAL pest control agents, BIOLOGICAL pest control, PEST control, PESTS, TOMATOES, and SPECIES pools

Tuta absoluta (Meyrick), a key pest of tomato, is quickly spreading over the world and biological control is considered as one of the control options. Worldwide more than 160 species of natural enemies are associated with this pest, and an important challenge is to quickly find an effective biocontrol agent from this pool of candidate species. Evaluation criteria for control agents are presented, with the advantages they offer for separating potentially useful natural enemies from less promising ones. Next, an aggregate parameter for ranking agents is proposed: the pest kill rate k m. We explain why the predator's intrinsic rate of increase cannot be used for comparing the control potential of predators or parasitoids, while k m can be used to compare both types of natural enemies. As an example, kill rates for males, females and both sexes combined of three Neotropical mirid species (Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (Stål)) were determined, taking all life-history data (developmental times, survival rates, total nymphal and adult predation, sex ratios and adult lifespan) into account. Based on the value for the intrinsic rate of increase (r m) for T. absoluta and for the kill rate k m of the predators, we predict that all three predators are potentially able to control the pest, because their k m values are all higher than the r m of the pest. Using only k m values, we conclude that E. varians is the best candidate for control of T. absoluta on tomato, with C. infumatus ranking second and M. basicornis last. [ABSTRACT FROM AUTHOR]

NILAPARVATA lugens, RICE, INSECT pests, SINGLE nucleotide polymorphisms, FOOD crops, and IDENTIFICATION

Rice is the most important staple food crop, and it feeds more than half of the world population. Brown planthopper (BPH) is a major insect pest of rice that causes 20–80% yield loss through direct and indirect damage. The identification and use of BPH resistance genes can efficiently manage BPH. A molecular marker-based genetic analysis of BPH resistance was carried out using 101 BC1F5 mapping population derived from a cross between a BPH-resistant indica variety Khazar and an elite BPH-susceptible line Huang–Huan–Zhan. The genetic analysis indicated the existence of Mendelian segregation for BPH resistance. A total of 702 high-quality polymorphic single nucleotide polymorphism (SNP) markers, genotypic data, and precisely estimated BPH scores were used for molecular mapping, which resulted in the identification of the BPH38(t) locus on the long arm of chromosome 1 between SNP markers 693,369 and id 10,112,165 of 496.2 kb in size with LOD of 20.53 and phenotypic variation explained of 35.91%. A total of 71 candidate genes were predicted in the detected locus. Among these candidate genes, LOC_Os01g37260 was found to belong to the FBXL class of F-box protein possessing the LRR domain, which is reported to be involved in biotic stress resistance. Furthermore, background analysis and phenotypic selection resulted in the identification of introgression lines (ILs) possessing at least 90% recurrent parent genome recovery and showing superior performance for several agro-morphological traits. The BPH resistance locus and ILs identified in the present study will be useful in marker-assisted BPH resistance breeding programs. [ABSTRACT FROM AUTHOR]

NILAPARVATA lugens, SINGLE nucleotide polymorphisms, LOCUS (Genetics), GENOTYPES, INSECT pests, and RICE

Rice is the most important staple food crop, and it feeds more than half of the world population. Brown planthopper (BPH) is a major insect pest of rice that causes 20–80% yield loss through direct and indirect damage. The identification and use of BPH resistance genes can efficiently manage BPH. A molecular marker-based genetic analysis of BPH resistance was carried out using 101 BC1F5 mapping population derived from a cross between a BPH-resistant indica variety Khazar and an elite BPH-susceptible line Huang–Huan–Zhan. The genetic analysis indicated the existence of Mendelian segregation for BPH resistance. A total of 702 high-quality polymorphic single nucleotide polymorphism (SNP) markers, genotypic data, and precisely estimated BPH scores were used for molecular mapping, which resulted in the identification of the BPH38(t) locus on the long arm of chromosome 1 between SNP markers 693,369 and id 10,112,165 of 496.2 kb in size with LOD of 20.53 and phenotypic variation explained of 35.91%. A total of 71 candidate genes were predicted in the detected locus. Among these candidate genes, LOC_Os01g37260 was found to belong to the FBXL class of F-box protein possessing the LRR domain, which is reported to be involved in biotic stress resistance. Furthermore, background analysis and phenotypic selection resulted in the identification of introgression lines (ILs) possessing at least 90% recurrent parent genome recovery and showing superior performance for several agro-morphological traits. The BPH resistance locus and ILs identified in the present study will be useful in marker-assisted BPH resistance breeding programs. [ABSTRACT FROM AUTHOR]

BROWN marmorated stink bug, STINKBUGS, HEMIPTERA, BIOLOGICAL control of insects, and BIOLOGICAL pest control

The Florida predatory stink bug, Euthyrhynchus floridanus L. (Hemiptera: Pentatomidae), is a generalist predator native to North America that feeds on a broad range of lepidopterous and heteropterous key pests in a great diversity of crops and non-crop situations. Feeding tests conducted in the laboratory to determine the most susceptible stage of the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), to third nymphal instar, and male and female E. floridanus, indicated that this predator has great potential for biological control of H. halys nymphs and adult stages. [ABSTRACT FROM AUTHOR]

MELIACEAE, HOST plants, HEMIPTERA, STINKBUGS, and INSECT antifeedants

Currently, the invasive brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is considered an agricultural and nuisance pest in Georgia. The invasive chinaberry tree, Melia azedarach L. (Meliaceae), commonly grows in dense thickets along roadsides, and in woodlands adjacent to agricultural crops across the southeastern USA. Thus, the objective of this study was to determine the potential of M. azedarach to serve as a host plant of H. halys by examining mortality and feeding of first and second instars on M. azedarach leaves vs. carrot (i.e., a control diet), and documenting presence of H. halys on M. azedarach in woodlands at 2 locations in Georgia where this stink bug has become established. Over all sampling dates and locations, the number of H. halys in chinaberry was very low (0.1 per tree), and only 3 late instars and 1 adult were observed feeding on M. azedarach at 1 field site late in the season. Percentage feeding by second instars of H. halys was lower for individuals given M. azedarach leaves vs. those provided with carrot, most likely indicating that compounds in M. azedarach have an antifeeding effect. In fact, mortality for second instars on M. azedarach leaves was very high, and thus we conclude that M. azedarach is an unsuitable host plant for H. halys. [ABSTRACT FROM AUTHOR]

STINKBUGS, INSECT rearing, HOSTS (Biology), AGRICULTURAL pests, BIOLOGICAL pest control agents, and ENCYRTIDAE

The species Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae) is currently being considered as a candidate for augmentative biological control agent (BCA) against several pests, including Halyomorpha halys (Stål) (Heteroptera: Pentatomidae). Protocols for mass production of a BCA need fundamental information on its biological attributes. Here we tested a possible laboratory host for the rearing of O. telenomicida: the common bug Graphosoma lineatum L. (Heteroptera: Pentatomidae). At tested conditions, O. telenomicida biological parameters were: rm 0.154, offspring production 84.07 specimens/female, sex ratio (% females) 71%, juvenile development time about 16 days, population doubling time 4.52 days, emergence rate about 90%. [ABSTRACT FROM AUTHOR]

FOSFOMYCIN, INFECTION, ESCHERICHIA coli, EPIDEMIOLOGY, and TEST methods

Objectives Fosfomycin susceptibility testing is complicated and prone to error. Before using fosfomycin widely in patients with serious infections, acquisition of WT distribution data and reliable susceptibility testing methods are crucial. In this study, the performance of five methods for fosfomycin testing in the routine laboratory against the reference method was evaluated. Methods Ten laboratories collected up to 100 ESBL-producing isolates each (80 Escherichia coli and 20 Klebsiella pneumoniae). Isolates were tested using Etest, MIC test strip (MTS), Vitek2, Phoenix and disc diffusion. Agar dilution was performed as the reference method in a central laboratory. Epidemiological cut-off values (ECOFFs) were determined for each species and susceptibility and error rates were calculated. Results In total, 775 E. coli and 201  K. pneumoniae isolates were tested by agar dilution. The ECOFF was 2 mg/L for E. coli and 64 mg/L for K. pneumoniae. Susceptibility rates based on the EUCAST breakpoint of ≤32 mg/L were 95.9% for E. coli and 87.6% for K. pneumoniae. Despite high categorical agreement rates for all methods, notably in E. coli, none of the alternative antimicrobial susceptibility testing methods performed satisfactorily. Due to poor detection of resistant isolates, very high error rates of 23.3% (Etest), 18.5% (MTS), 18.8% (Vitek2), 12.5% (Phoenix) and 12.9% (disc diffusion) for E. coli and 22.7% (Etest and MTS), 16.0% (Vitek2) and 12% (Phoenix) for K. pneumoniae were found. None of the methods adequately differentiated between WT and non-WT populations. Conclusions Overall, it was concluded that none of the test methods is suitable as an alternative to agar dilution in the routine laboratory. [ABSTRACT FROM AUTHOR]