Higher Mite Densities Research Articles

Beyond the Surface: Understanding Demodex and Its Link to Blepharitis and Facial Dermatoses.

Demodex represents the most frequent ectoparasite found in humans. Although Demodex mites are considered commensals of human pilosebaceous units, an abnormally high mite density can cause several ocular and cutaneous symptoms and signs, sometimes to a severe degree. Both Demodex spp. (folliculorum and brevis) play a significant part in eye pathology and facial dermatoses. These mites have been related to blepharitis, ocular rosacea, meibomian gland dysfunction and various skin diseases, including rosacea, demodicosis and seborrheic dermatitis. Understanding the importance of Demodex in both eye and skin conditions is crucial for accurate diagnosis and appropriate management strategies, which may involve targeted treatments to control the mite population and reduce associated symptoms.

The mite Acarus farris inducing defensive behaviors and reducing fitness of termite Coptotermes formosanus: implications for phoresy as a precursor to parasitism

BackgroundThe ecology and evolution of phoretic mites and termites have not been well studied. In particular, it is unknown whether the specific relationship between mites and termites is commensal or parasitic. High phoretic mite densities have often been found to occur in weak termite colonies, suggesting that the relationship is closer to that of parasitism than commensalism.ResultsTo examine this, Coptotermes formosanus was used as a carrier, and Acarus farris as the phoretic mite. We used video recordings to observe termite social immunity behaviors and bioassay to examine termite fitness. Our results showed that the attachment of the mite on the termite can enhance termite social immunity behaviors like alarm vibration and grooming frequency while decreasing the duration of individual grooming episodes in phoretic mites. Further, A. farris phoresy led to a 22.91% reduction in termite abdomen volume and a 3.31-fold increase in termite mortality.ConclusionsWhen termites groom more frequently, the consequence is short duration of grooming bouts. This may be indicative of a trade-off which provides suggestive evidence that frequent social behaviors may cost termites energy. And this caused phoretic behavior hastened termites’ death, and helped propagate the population of mites feeding on dead termites. So, it provides a case for phoresy being a precursor to parasitism, and the specific relationship between A. farris and C. formosanus is closer to parasitism than to commensalism.

Assessment of the host-range and impact of the mite, Aculus crassulae, a potential biological control agent for Australian swamp stonecrop, Crassula helmsii

The non-native aquatic weed Crassula helmsii, or Australian swamp stonecrop, has become widespread and a major problem in aquatic habitats in the UK and North-West Europe, with negative impacts reported from ecologically important habitats. As very few effective traditional management tools are available to land managers, a biological control project was initiated in the UK. An Australian phytophagous mite, Aculus crassulae (Acari: Eriophyidae) was evaluated as a potential agent for C. helmsii under laboratory conditions in no-choice and choice host plant tests. These demonstrated that A. crassulae is host specific to C. helmsii, with only minor exploratory feeding observed on the native congener, C. aquatica, under no-choice tests, and no damage recorded in choice tests. The impact of A. crassulae on the growth of C. helmsii was also investigated by applying two different mite densities to plants. Both densities, especially the higher mite density, caused a significant reduction in plant growth by the end of the experimental period. Secondary shoot number and length, number of nodes and new leaf pairs were reduced by the mites during the course of the experiment, but the largest impact was on the reduction of plant height. The host specific nature of A. crassulae and the observed reduction in these significant growth parameters demonstrate the potential A. crassulae has as a biological control agent for C. helmsii in the UK and Europe.

Demodectic mange in threatened southern sea otters (Enhydralutrisnereis)

Southern sea otters (Enhydra lutris nereis) rely on intact pelage for thermoregulation, and thus clinically significant demodicosis and associated alopecia can cause morbidity and death. This study aimed to describe lesions associated with follicular Demodex sp. infestation, estimate the prevalence and intensity of infestation, describe mite distribution across key anatomical regions, and assess mite presence or absence in relation to lesions and host risk factors. Twenty necropsied, wild southern sea otters that stranded along the central California coast from 2005 to 2018. Grossly normal and abnormal integument from the head, perineum, genitals, mamillary papillae and limbs was assessed microscopically for mites and mite-associated pathological findings. Intrafollicular mites were observed in the integument of 55% of otters and 20% had clinical demodicosis. Demodicosis was considered to be contributory to death or euthanasia in two cases. Although Demodex sp. mites often were observed microscopically in grossly normal skin, the presence of multiple densely-packed intrafollicular mites generally was associated with pigmentary incontinence, ectatic follicles, lymphoplasmacytic perifolliculitis, and neutrophilic and lymphoplasmacytic, dermal inflammation. Other findings included epidermal hyperplasia, orthokeratotic hyperkeratosis of epidermis and follicular epithelium, concurrent pyoderma and cell necrosis. Perioral integument, especially of the chin, had the highest prevalence of mites and the highest mite density, suggesting facial contact as a means of mite transmission. Our research confirmed demodectic mange as a contributor to morbidity and mortality in sea otters, with important implications for clinical care, rehabilitation and conservation.

Seasonal population dynamics of Aceria oleae (Nalepa, 1900) (Acari: Eriophyidae) in generative organs of olives in Hatay Province, Turkey

Olive, Olea europaea L., is an evergreen tree native to areas with Mediterranean climates. Its fruit and oil are key ingredients in the Mediterranean cuisine. Olive gall mite, Aceria oleae (Nalepa, 1900) (Acari: Eriophyidae) is a mite species that feeds on olive leaves, buds or flowers. This study was conducted to determine the population dynamics of A. oleae in generative organs of olive in Altınözü, Antakya and Samandağ Districts of Hatay between in April and October 2017 and 2018. The highest mite density was detected in Altınözü during the flowering period in 2017 and the budding period in 2018; and a second peak was seen during fruiting period for both years. A peak occurred in samples collected from Antakya for both years (in fruit stage, June 2017, and in budding stage, April 2018) but no prominent peak was noted Samandağ samples. A high rate of flower and fruit dropping was observed and this concurred with noticeable decreases in A. oleae population in Altınözü and Antakya Districts in both years. Three phytoseiid species, Typhlodromus ( Anthoseius ) athenas Swirski & Ragusa, 1976 (44%), Typhlodromus ( Anthoseius ) rapidus Wainstein & Arutunjan, 1968 (29%) and Typhlodromus ( Typhlodromus ) athiasae Porath & Swirski, 1965 (26%) (Acari: Phytoseiidae) were detected in these orchards. It is thought they probably fed on A. oleae since their primary prey, tetranychid mites were unavailable. Correlation results showed that population sizes of A. oleae did not decrease significantly with temperature and humidity in 2017. In 2018, the population was negatively correlated with temperature, but no significant increase occurred as humidity rose.

Age-Dependent Functional and Numerical Responses of Neoseiulus cucumeris (Acari: Phytoseiidae) on Two-Spotted Spider Mite (Acari: Tetranychidae).

The age-specific functional and numerical responses of Neoseiulus cucumeris Oudemans (Mesostigmata: Phytoseiidae) on eggs of the two-spotted spider mite, Tetranychus urticae Koch (Prostigmata: Tetranychidae), were assessed in the laboratory using bean leaf discs. Densities of 2, 4, 8, 16, 32, 64, and 128 prey were provided to 4- (protonymph), 6- (deutonymph), 8-, 13-, 18-, 23-, 28-, 33-, and 40-d-old N. cucumeris individuals. The functional response of 28- and 40-d-old N. cucumeris fitted type II, whereas the other ages displayed a type III functional response. The longest handling time observed at the age of 4 d was 0.515 h, whereas the shortest handling time and highest value of maximum attack rate (T/Th) were associated with the age of the 28-d-old treatment (0.261 h and 91.95 prey/d, respectively). The numerical response of N. cucumeris showed a significant increase with increasing prey density, but its rate gradually decreased at higher densities. Therefore, the efficiency of conversion of ingested food was relatively higher at low two-spotted spider mite densities, whereas it was reduced at high two-spotted spider mite densities. The stronger functional response and predation capacity of N. cucumeris on two-spotted spider mite eggs indicated the high potential of this predatory mite as an effective biological control agent against two-spotted spider mite especially at its early and middle ages and also when higher prey densities are present.

House dust mites (Acari: Astigmata) from mattresses in Panama

The name “house dust mites” is commonly used to refer to species of mites belonging mainly to the Pyroglyphidae family (Astigmata) that are found in association with dust in the human dwellings. They represent the main source of allergens in the home and can cause allergic diseases. Mattresses often provide ideal conditions for mite colonization. In order to compare the diversity of house dust mites in the provinces of Panama and Panama Oeste in 2015, we collected dust from the surfaces of mattresses over an area of one square meter using the vacuum method. We obtained 50 samples using the vacuum method and recovered 10,225 mites. We found that the mites in our samples belonged to 15 families, 15 genera and 22 morphospecies. Relatively, high mean densities of mites per gram of dust on mattresses were obtained in the provinces of Panama (3,577 mites/g of dust) and Panama Oeste (6,273 mites/g of dust). The mite Blomia tropicalis was the most abundant species in mattresses in the Province of Panama and Dermatophagoides pteronyssinus was the most frequent one in Panama Oeste. Our results indicate that the mite community in mattresses is similar between PA and PO. However, our results differ significantly from those found in bedroom floors in a previous study. These differences correspond to a lower species richness, higher density and relative abundance of Astigmata mites in mattresses.

Temperature stress induces mites to help their carrion beetle hosts by eliminating rival blowflies.

Ecological conditions are known to change the expression of mutualisms though the causal agents driving such changes remain poorly understood. Here we show that temperature stress modulates the harm threatened by a common enemy, and thereby induces a phoretic mite to become a protective mutualist. Our experiments focus on the interactions between the burying beetle Nicrophorus vespilloides, an associated mite species Poecilochirus carabi and their common enemy, blowflies, when all three species reproduce on the same small vertebrate carrion. We show that mites compete with beetle larvae for food in the absence of blowflies, and reduce beetle reproductive success. However, when blowflies breed on the carrion too, mites enhance beetle reproductive success by eating blowfly eggs. High densities of mites are especially effective at promoting beetle reproductive success at higher and lower natural ranges in temperature, when blowfly larvae are more potent rivals for the limited resources on the carcass.

Resistance of some commercial walnut cultivars and genotypes to Aceria tristriata (Nalepa) (Acari: Eriophyidae) and its correlation with some plant features.

The walnut leaf gall mite (WLGM) (Aceria tristriata (Nalepa)) is one of the major pests of walnut in western Iran. The use of a resistant variety is an economical and environment-friendly method of pest control. The aim of the present study is to assess resistance of some walnut cultivars and genotypes in relation to WLGM. Also, the current research aimed to study a possible correlation between resistance with plant morphological and biochemical features. Based on the leaf damage index (number of galls per leaf and plant, the percentage of infested leaves and the percentage of leaf injury area) induced by WLGM, the studied cultivars and genotypes were classified into four groups from susceptible to approximately resistant. Free-choice experiments indicated that Jamal and Chandler cultivars were colonized by lower densities of WLGM, whereas Seedling, Hartly, Lara and Z60 hosted denser populations. In antibiosis assay, the highest mite density was created in the galls on the leaves of Seedling and Hartly, whereas lowest mite density was observed in galled leaves of Chandler and Jamal cultivars. Results from biochemical assays showed that nearly all evaluated biomarkers had negative correlation with number of galls per leaf and mite density. Generally, resistant cultivars (Chandler, Jamal and Pedro) significantly produced defensive compounds more than those of controls after mite infestation. Also, it is worth noting that, the content of photosynthetic pigments significantly reduced in susceptible cultivars after mite infestation. The obtained results from this study can be useful for provisional resistance screening. © 2019 Society of Chemical Industry.

Transcriptomic and proteomic response of Manihot esculenta to Tetranychus urticae infestation at different densities.

Tetranychus urticae (Acari: Tetranychidae) is an extremely serious cassava (Manihot esculenta) pest. Building a genomic resource to investigate the molecular mechanisms of cassava responses to T. urticae is vital for characterizing cassava resistance to mites. Based on the tolerance of cassava varieties to mite infestation (focusing on mite development rate, fecundity and physiology), cassava variety SC8 was selected to analyze transcriptomic and proteomic changes after 5days of T. urticae feeding. Transcriptomic analysis revealed 698 and 2140 genes with significant expression changes under low and high mite infestation, respectively. More defense-related genes were found in the enrichment pathways at high mite density than at low density. In addition, iTRAQ-labeled proteomic analysis revealed 191 proteins with significant expression changes under low mite infestation. Differentially expressed genes and proteins were mainly found in the following defense-related pathways: flavonoid biosynthesis, phenylpropanoid biosynthesis, and glutathione metabolism under low-density mite feeding and plant hormone signal transduction and plant-pathogen interaction pathways under high-density mite feeding. The plant hormone signal transduction network, involving ethylene, jasmonic acid, and salicylic acid transduction pathways, was explored in relation to the M. esculenta response to T. urticae. Correlation analysis of the transcriptome and proteome generated a Pearson correlation coefficients of R = 0.2953 (P < 0.01), which might have been due to post-transcriptional or post-translational regulation resulting in many genes being inconsistently expressed at both the transcript and protein levels. In summary, the M. esculenta transcriptome and proteome changed in response to T. urticae, providing insight into the general activation of plant defense pathways in response to mite infestation.

Wind speed predicts population dynamics of the eriophyid mite Floracarus perrepae on invasive Old World climbing fern (Lygodium microphyllum) in a shade house colony.

Lygodium microphyllum is one of the most noxious invasive plants in Florida, USA, smothering native vegetation in cypress swamps, pine flatwoods, and Everglades tree islands and altering fire regimes. The eriophyid mite Floracarus perrepae was introduced from Australia to help control L. microphyllum infestations. While F. perrepae exhibits high population growth rates in its native range, its population dynamics in Florida are unknown, particularly the dynamics that occur within the leaf roll galls the mite induces on the margins of leaves. Here, we monitored a shade house colony of F. perrepae in south Florida for 2years to identify seasonal patterns and potential climate drivers of within-gall mite density. Gall dissections of mite-infested colony plants were performed monthly. Mite density within galls exhibited two cycles per year: a strong cycle that boomed in spring and busted in summer, and a weak cycle that moderately increased mite density in fall and declined in winter. Climate variables, particularly those related to wind speed, were positively associated with higher mite density. Our study sheds light on the within-gall dynamics of F. perrepae and suggests that the highest within-gall mite densities occur in the spring and fall.

Impact of the erineum strain of Colomerus vitis (Acari: Eriophyidae) on the development of plants of grapevine cultivars of Iran.

The present experiment was aimed at determining the influence of the grape erineum strain of Colomerus vitis (GEM) (Acari: Eriophyidae) on responses of local grapevine cultivars. GEM was applied at five density levels to each of five cultivars, i.e. Shahani, Sahebi Uroomie, Khalili Bovanat, Rishbaba and Sezdang Ghalat (listed from early to late grape ripening). The experiment was performed in a full factorial design (12 replicates each) and effects of the mite on the relative content of leaf chlorophyll, internode and cane length, leaf area and weight, number and size of the erinea, and percentage of leaves with erinea were investigated. Also mite density on leaves and in buds was assessed. Data were analyzed with a two-way ANOVA followed by Tukey's test to separate means among treatment levels and cultivars. The relative content of chlorophyll (expressed in Spad units) in infested leaves was reduced along with an increase in mite density and it was shown to be highly significant at the two higher mite density levels for Khalili Bovanat, Rishbaba and Sezdang Ghalat; Shahani and Sahebi Uroomie leaves appeared to be less affected by mite infestation. The highest mite density treatment displayed a strong correlation with weight (positive correlation) and size (negative correlation) of the leaves of four cultivars; leaves of Sahebi Uroomie appeared to be less affected. The reduced internode length was weak in infested plants. Most infested plants produced shorter canes and their lengths appeared to have a strong negative correlation with the highest mite density in four cultivars; canes of Sahebi Uroomie did not appear affected. At the highest mite density, canes of Khalili Bovanat and Sahebi Uroomie displayed the most and the least shortening effects, respectively. The percentage of leaves with erinea, as well as the number of erinea per leaves and the diameter of erinea increased along with the mite population density. The mite densities in buds (April 2014) and on leaves with erinea (in November 2013) were higher at the highest treatment level in the medium-late (Rishbaba) and late ripening (Sezdang Ghalat) cultivars, than in the early and early-medium ripening ones. Almost all data collected in the current experiment allowed the conclusion that Sahebi Uroomie and Shahani were less affected than the other cultivars (Khalili Bovanat, Rishbaba and Sezdang Ghalat).

Varroa-specific hygienic behavior of Apis mellifera scutellata in Kenya

Varroa-specific hygienic behavior is a hereditary trait of honey bee (Apis mellifera), which supports resistance to Varroa destructor. This study investigated the response of Apis mellifera scutellata to Varroa-infested worker brood cells in Kenya, East Africa. Uncapping, removal of the brood, and disappearance of the introduced mite were recorded in a total of 690 cells into which live mites were introduced. We recorded a high proportion of untouched cells in controls (median, 80%) compared to manipulated cells in which mites had been introduced (median, 12.5%) with a significant difference (GLMM, p < 0.001). Mites were removed and cells were recapped in about 26% of the artificially infested brood cells. When ten, eight, and five mites were singly introduced in closely neighboring brood cells, hygienic bees were more responsive in the high mite density regime of eight and ten mites, an indication of a possibility that chemicals play a role in identification of Varroa-infested brood cells.

The influence of Tetranychus cinnabarinus-induced plant defense responses on Aphis gossypii development

Carmine spider mites (Tetranychus cinnabarinus) and cotton aphids (Aphis gossypii) are both serious pests of cotton, and cause reductions in yields of this key agricultural crop. In order to gain insights into how plant defense responses induced by one herbivore species affect the behavior and performance of another, we examined how infestation with T. cinnabarinus influences the development of A. gossypii using cotton as a model. In this study, we measured the activities of several important biochemical markers and secondary metabolites in the leaves of cotton seedlings responding to infestation by T. cinnabarinus. Furthermore, the influences of T. cinnabarinus infestation on the development of A. gossypii in cotton were also examined. Our data showed that the activities of several key defense enzymes, including phenylalanine ammonia-lyase (PAL), peroxidase (POD), lipoxygenase (LOX), and polyphenol oxidase (PPO), were substantially increased in cotton seedlings responding to spider mite infestation. Further, the contents of gossypol and condensed tannins, key defensive compounds, were significantly enhanced in leaves of cotton seedlings following T. cinnabarinus infestation. Moreover, the T. cinnabarinus-induced production of defense enzymes and secondary metabolites was correlated with infestation density. The developmental periods of A. gossypii on cotton seedling leaves infested with T. cinnabarinus at densities of 10 and 15 individuals cm−2 were 1.16 and 1.18 times that of control, respectively. Meanwhile, the mean relative growth rates of A. gossypii on cotton leaves infested with T. cinnabarinus at densities of 8, 10 and 15 individuals cm−2 were significantly reduced. Therefore, these data suggested that the developmental periods of A. gossypii were significantly lengthened and the mean relative growth rates were markedly reduced when cotton aphids were reared on plants infested with high densities of spider mites. This research sheds light on the role that inducible defense responses played in plant-mediated interspecific interactions between T. cinnabarinus and A. gossypii.

Minimal Pruning and Reduced Plant Protection Promote Predatory Mites in Grapevine.

Improving natural pest control by promoting high densities of predatory mites (Acari: Phytoseiidae) is an effective way to prevent damage by pest mites (e.g., Eriophyidae, Tetranychidae) and other arthropod taxa that can cause serious damage to vineyards. Here, we investigate the influence of innovative management on predatory mite densities. We compare (i) full versus reduced fungicide applications and (ii) minimal pruning versus a traditional trellis pruning system in four fungus-resistant grapevine varieties. As predatory mites also feed on fungus mycelium, we assessed fungal infection of grapevine leaves in the experimental vineyard. Predatory mites were significantly more abundant in both minimal pruning and under reduced plant protection. Increases in predatory mites appeared to be independent of fungal infection, suggesting mostly direct effects of reduced fungicides and minimal pruning. In contrast to predatory mites, pest mites did not increase under innovative management. Thus, conditions for natural pest control are improved in fungus-resistant grapevines and under minimal pruning, which adds to other advantages such as environmental safety and reduced production cost.

Interspecific Interactions and the Scope for Parent-Offspring Conflict: High Mite Density Temporarily Changes the Trade-Off between Offspring Size and Number in the Burying Beetle, Nicrophorus vespilloides.

Parents have a limited amount of resources to invest in reproduction and commonly trade-off how much they invest in offspring size (or quality) versus brood size. A negative relationship between offspring size and number has been shown in numerous taxa and it underpins evolutionary conflicts of interest between parents and their young. For example, previous work on vertebrates shows that selection favours mothers that produce more offspring, at the expense of individual offspring size, yet favours offspring that have relatively few siblings and therefore attain a greater size at independence. Here we analyse how this trade-off is temporarily affected by stochastic variation in the intensity of interspecific interactions. We examined the effect of the mite Poecilochirus carabi on the relationship between offspring size and number in the burying beetle, Nicrophorus vespilloides. We manipulated the initial number of mites in the reproductive event (by introducing either no mites, 4 mites, 10 mites, or 16 mites), and assessed the effect on the brood. We found a similar trade-off between offspring size and number in all treatments, except in the '16 mite' treatment where the correlation between offspring number and size flattened considerably. This effect arose because larvae in small broods failed to attain a high mass by dispersal. Our results show that variation in the intensity of interspecific interactions can temporarily change the strength of the trade-off between offspring size and number. In this study, high densities of mites prevented individual offspring from attaining their optimal weight, thus potentially temporarily biasing the outcome of parent-offspring conflict in favour of parents.

On the population biology of Sarcoptes scabiei infesting Iberian ibex (Capra pyrenaica)

ABSTRACTIn this study, we analysed the Sarcoptes scabiei infrapopulations of 315 Iberian ibex (Capra pyrenaica) by means of skin digestion and differential mite counts. Mean density reached 178.2 mites/cm2 (range: 0.71–4514.29). Although the most frequently affected zones were hosts’ extremities and withers, higher mite densities were obtained from lips and extremities, suggesting that indirect infection through the substrate could also play a role in the disease epidemiology, together with direct transmission. The sex ratio of mites was female-biased (mean: 5.18 ♀♀/♂, range: 0.5–17). Larvae were more frequently found (nearly 50% of specimens) than nymphs, adult females or adult males. Mite density varied significantly between years and decreased with host age. Most of the variance was explained by the year, host sex, weight and kidney fat index (KFI). Taking into account the catabolic nature of the disease, our results suggest that hosts in good body condition could evidence a certain degree of resistance to the disease, which presumably has a genetic basis.

Diversity and population dynamics of Ascidae, Blattisociidae and Melicharidae (Acari: Mesostigmata) in tropical flowers in Brazil.

Cultivation of tropical flowers has expanded considerably in Brazil, justifying efforts to determine the arthropods associated with it. Heliconia species are some of the most important tropical flowers in Brazil. Mites of the families Ascidae, Blattisociidae and Melicharidae are commonly found on those plants. They disperse from flower to flower on hummingbirds. The objective of this study was to identify the diversity of mites of this group in tropical flowers, with emphasis on Heliconia species, in Brazil and to determine the fluctuation of the population of these mites in Piracicaba, Sao Paulo state. Specimens from Amazonas, Bahia, Pernambuco, Minas Gerais, Rio de Janeiro, Santa Catarina and São Paulo States were examined. Mites of the genera Asca and Iphidozercon (Ascidae), Cheiroseius and Lasioseius (Blattisociidae), and Proctolaelaps and Tropicoseius (Melicharidae) were collected in flowers of four plant families, with Lasioseius being the most diverse genus. Overall, most specimens found belonged to Tropicoseius, especially Tropicoseius venezuelensis Baker & Yunker; this was the dominant species on five of 13 Heliconia species/hybrids considered in this study. Samples of panicles of Heliconia rostrata Ruiz & Pavón were collected every 2weeks, in Piracicaba. Six species of those mite families were found, among which Tropicoseius heliconiae Baker & Yunker and T. venezuelensis were the most numerous. The highest population levels of mites of those three families occurred at the beginning and at the end of the year, coinciding with the highest levels of rainfall, relative humidity and temperature, when plant flowers were most numerous and vigorous. Along each panicle, the highest mite densities were found in inflorescences of the three distal eighths of the panicles, where nectar and pollen were probably most abundant.

Anafilaxia oral por ingestión de alimentos contaminados con ácaros en Ciudad de Panamá, 2011-2014

Antecedentes: la anafilaxia oral por ácaros, o síndrome de las panquecas, ocurre cuando individuos atópicos ingieren alimentos elaborados con harina de trigo contaminada con ácaros, lo que induce reacciones alérgicas moderadas o severas, incluso fatales. Los reportes provienen de ambientes tropicales y subtropicales, donde las condiciones para la proliferación de ácaros domésticos son favorables. Se ha encontrado una asociación importante con la hipersensibilidad a ácido acetilsalicílico (AAS)-antiinflamatorios no esteroides (AINES) y el ejercicio físico. Objetivo: documentar el estudio clínico y descriptivo de casos de anafilaxia oral por ácaros atendidos en Ciudad de Panamá durante los años 2011 a 2014.Material y método: estudio clínico descriptivo y retrospectivo, que incluyó pruebas cutáneas de punción para cinco especies de ácaros domésticos. La identificación taxonómica de los ácaros se realizó bajo microscopio y se calculó la densidad de ácaros por gramo de alimento en tres casos.Resultados: se estudiaron 10 casos compatibles con anafilaxia oral por ácaros, la panqueca fue el alimento implicado con más frecuencia. Los primeros síntomas aparecieron entre 25 y 60 minutos después de la ingestión del alimento. Todos los pacientes fueron adultos jóvenes atópicos, cuatro con hipersensibilidad a AAS-AINES. Los pacientes resultaron positivos a las pruebas cutáneas de punción para los ácaros: Blomia tropicalis, Dermatophagoides pteronyssinus y Suidasia pontifica. Tres muestras de harina de trigo estudiadas motraron altas densidades de ácaros.Conclusiones: la panqueca fue el alimento implicado con más frecuencia en los casos de anafilaxia oral por ácaros. Suidasia pontifica y Blomia tropicalis parecen ser los ácaros más importantes relacionados con este síndrome en nuestro país.

Early establishment of the phytoseiid mite Amblyseius swirskii (Acari: Phytoseiidae) on pepper seedlings in a Predator-in-First approach.

The establishment of biocontrol agents is critical for success of biological control strategies. Predator-in-First (PIF) is a prophylactic control strategy that aims to establish predators before the appearance of pests in an agro-ecosystem. PIF uses the ability of generalist phytoseiid mites to survive, develop and reproduce on pollen and thus establish in the absence of prey. The early establishment of populations of natural enemies helps control the pests at their incipient stage of infestation. The current study was undertaken to screen pepper cultivars for their ability to support populations of the predatory mite Amblyseius swirskii Athias-Henriot in the absence of prey. Twenty-nine pepper cultivars (11 hot and 18 sweet) were tested through a series of experiments, and four cultivars (7141, 992-7141, FPP7039 and FPP9048) were found to sustain A. swirskii populations throughout the study period. The initial application of pollen was important for establishment and maintenance of the predatory mites within the greenhouse system. Among the three screening experiments, high densities of mites were obtained in the experiment where 20 mites were released per plant, even reaching densities of >100 mites/plant. Recovery of predatory mites was significantly higher (ca. 2-3 fold) on the four pepper cultivars when predatory mites were mass released using an indirect method (banker plants) than when they were released directly on the seedlings, suggesting an advantage of passive continuous release. Future work will evaluate the selected pepper cultivars with the PIF strategy under greenhouse and field production conditions.