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PubMed1992

Combination of patch test and IgE for dust mite antigens differentiates 130 patients with atopic dermatitis into four groups.

BACKGROUND: Patients with atopic dermatitis sometimes have positive responses to patch testing (PT) with dust mite antigens, which is believed to correlate with the elevated levels of specific IgE for those antigens. OBJECTIVE: The purpose of this study is to identify the correlation between the PT and serum IgE concerning the mite antigens. METHODS: We studied 130 patients with atopic dermatitis by the PT reaction and the serum level of specific IgE for Dermatophagoides pteronyssinus antigens. RESULTS: Fifty-one of the 130 patients assessed as PT-positive had either high (32 of 130 patients; 24.6%) or low or no (19 of 130 patients; 14.6%) levels of mite-specific IgE; there was a significant difference between the groups with elevated and low IgE. Similarly, a total of 79 PT-negative patients also showed an elevated or low mite-specific IgE (42 of 130 patients [32.3%] or 37 of 130 patients [28.5%], respectively). It was noted that clinical morphologic findings were peculiar to three of the four groups; however, the patients who were PT-negative with a low IgE (37 of 130 patients) showed no particular clinical lesions. CONCLUSION: Comparing the results from our 130 patients, there was no correlation between the serum IgE level and the PT reaction for dust mite antigens. Conversely, the results of PT and mite-specific IgE could be used to divide these patients into four distinct groups, each with its own particular clinical morphology, suggesting the heterogeneity of this disease.

Adolescent↗
PubMed2005

Cat and dust mite sensitivity and tolerance in relation to wheezing among children raised with high exposure to both allergens.

BACKGROUND: Recent evidence has suggested that high exposure to cat allergens is associated with decreased prevalence of sensitization to cat and, in some studies, decreased asthma. OBJECTIVE: Our objective was to study antibodies to cat and mite allergens and their relationship to wheezing in a country with high exposure to both allergens. METHODS: Sera from 112 wheezing and 112 control children aged 10 to 11 years in a nested case-control study in New Zealand were assayed for specific IgE antibody, as well as IgG antibody and IgG4 antibody, to Der p 1 and Fel d 1. RESULTS: IgE antibody to both mite (99/224) and cat (41/224) were strongly associated with wheezing (odds ratios, 5.2 and 6.5, respectively). Children who had ever lived with a cat were less likely to have IgE antibody to cat (20/141 vs 21/83, P < .04); however, cat ownership had no effect on IgE antibody to mite (67/141 vs 32/83, P = .23). Among sensitized children, cat ownership was associated with a lower prevalence of IgE antibody to cat (28% vs 66%, P < .001), and this analysis remained significant after exclusion of children whose families had chosen not to own a cat. Among sensitized subjects, the mean titer of IgE antibody to cat (1.7 IU/mL) was 10-fold lower than for mite (22.1 IU/mL). A cat in the home had no significant effect on endotoxin or mite allergen in house dust, whereas cat allergen was much higher (40.8 vs 3.3 microg/g). CONCLUSION: The response to these 2 allergens was distinct on the basis of the prevalence of sensitization, the titer of IgE antibody, and the effect of cat ownership. The results suggest that induction of tolerance to cat allergen is an allergen-specific phenomenon that cannot be attributed to endotoxin or family choice. The strength of the IgE antibody response to dust mite in humid climates could contribute to the increased prevalence and severity of asthma.

Allergens↗
PubMed2005

First detection of Anaplasma phagocytophilum in quill mites (Acari: Syringophilidae) parasitizing passerine birds.

Forest passerine birds and their ectoparasites: Ixodes ricinus ticks and Syringophilidae quill mites were surveyed for infection with Anaplasma phagocytophilum in west-central Poland. Of 126 birds captured from May to June of 2002, 71 (56.3%) comprising eight species, hosted immature I. ricinus ticks. A total of 383 ticks and 71 blood samples collected from tick-infested birds were investigated by PCR. The pathogen was not detected in either bird-derived ticks or in blood samples. Among the captured birds, a total of 14 individuals representing four species hosted quill mites from the family Syringophilidae. Three of the 14 mite pools recovered from the 14 mite-infested birds harbored A. phagocytophilum DNA by amplifying both the epank1 and p44 gene. The PCR-positive pools originated from one blackbird and two starlings. The specific biology of syringophilid mites, which parasitize exclusively inside the quill of feathers, feeding on host subcutaneous fluids, implies that they must have acquired the pathogen from a bacteremic bird. These results provide the first indirect evidence that at least some passerine hosts are prone to develop systemic infection with A. phagocytophilum under natural conditions. Consequently, the infected quill mites may serve as a "biological marker" of past or current infection with the agent within birds.

Acari↗
PubMed1999

Grooming decisions by damselflies, age-specific colonisation by water mites, and the probability of successful parasitism.

We examined whether host damselflies (Ischnura verticalis) in different stages of development were differentially susceptible to parasitism by larval water mites (Arrenurus pseudosuperior). We found that mites were successful in reaching the parasitic phase more often if they colonised hosts closer to emergence. Thus, we predicted that more mites should colonise damselflies closer to emergence and damselflies closer to emergence should spend more time defending against mites. We found that mites colonised damselflies closer to emergence in one of two experiments, but that damselflies in different stages of development did not differ in time spent defending against mites.

Animals↗
PubMed1995

Sensitization to mite allergens is a risk factor for early and late onset of asthma and for persistence of asthmatic signs in children.

BACKGROUND: To describe the natural history of asthma between the ages of 7 and 10 years and to analyze risk factors for prevalences, as well as new onset of asthma-like symptoms, a longitudinal study of 1812 children was conducted. METHODS: In four surveys, each 1 year apart, four asthma-like symptoms and several hypothetical risk factors were ascertained through standardized questionnaires. Sensitization to seven common inhalant allergens was measured by skin prick testing. Exposure to mite allergens (Der p I, Der f I) was assessed by measuring the antigen concentrations in the dust of each child's mattress. Occurrence of more than one asthma-like symptom closely related to the practioner's diagnoses of bronchial asthma and recurrent wheezy bronchitis was used as the outcome variable. RESULTS: After an initial prevalence of 14.5%, new onset of symptoms in children unaffected at the beginning was reported in 7.2% during the 3 years. Of the factors explaining prevalence and persistence of asthma-like symptoms (sensitization to mite allergens and animal danders, history of hay fever and eczema, low gestational age, male gender, parental atopy), only sensitization to mite allergens (odds ratio = 2.3, 95% confidence interval = 1.1-4.7) and parental atopy (odds ratio = 2.1, 95% confidence interval = 1.2-3.7) were also significantly associated with new onset. In a relatively small number of sensitized subjects with new onset of symptoms (n = 31), mite antigen concentration did not appear to be associated with incidence of symptoms. CONCLUSION: Sensitization to mite allergens antedated the onset of asthma-like symptoms, and no strong effect of allergen exposure on clinical development could be found. Thus the primary focus should be on preventing sensitization to mite allergens by implementing avoidance measures in infancy or at early school age in order to reduce the onset of asthma at a later stage.

Allergens↗
PubMed1997

House dust mite avoidance measures improve peak flow and symptoms in patients with allergy but without asthma: a possible delay in the manifestation of clinical asthma?

BACKGROUND: Asthma caused by allergy to house dust mite is a growing problem. Patients with allergy who do not have asthma (yet) might develop asthma depending on exposure to precipitating factors. OBJECTIVE: We sought to determine whether house dust mite avoidance measures have an effect on the development of asthma. METHODS: Patients with allergy (n = 29) who had no diagnosis of asthma (FEV1 of 99.1% +/- 10.6% of predicted, peak flow variability of 5.21% +/- 3.41%, reversibility of FEV1 after 400 microg salbutamol of 3.92% +/- 3.75% according to the reference values) were randomly allocated (subjects blinded) to a treatment (n = 16) and a placebo group (n = 13). House dust mite avoidance treatment consisted of applying Acarosan (Allergopharma, J. Ganzer KG, Hamburg, Germany) (the placebo group used water) to the floors (living room, bedroom), and the use of covers for mattresses and bedding that were impermeable to house dust mite (the placebo group used cotton covers for mattresses only). We tested whether the intervention had an effect on peak flow parameters and asthma symptom scores during 6 weeks of treatment. RESULTS: Significant improvements were seen in the treatment group in symptom scores (Borg score) for disturbed sleep, breathlessness, wheeze, and overall symptom score. Slight but statistically significant improvements in peak flow (morning, evening, and variability) were seen in the treatment group also. No significant changes were seen in the placebo group. CONCLUSIONS: Although this study is not long enough to study the development of asthma, the results indicates that house dust mite avoidance measures had an effect on peak flow parameters and asthma symptoms in patients with allergy but without asthma. These findings might implicate that a shift in developing clinically manifest asthma could be achieved with house dust mite avoidance measures. To give a better answer to whether preventing the development of asthma is possible, larger studies with a longer follow-up period are necessary.

Adolescent↗
PubMed1998

Preventive effect of bedding encasement with microfine fibers on mite sensitization.

BACKGROUND: The indoor levels of mite allergens are known to determine the thresholds of sensitization and asthma exacerbation. However, the method for preventing mite sensitization by reducing the levels of house dust mites (HDMs) is not well established. OBJECTIVE: We investigated whether mite-blocking bedding encasing made from microfine fibers can prevent infants from being sensitized to HDMs. METHODS: Fifty-seven Japanese infants with atopic dermatitis who had high levels of IgE antibodies against either egg white, cow's milk, or soybean (but not against HDMs) were randomly chosen and divided into two groups. Thirty families of atopic infants (group A) were instructed to decrease HDMs by controlling the indoor environment, including bedding cleaning, whereas 27 families receiving the same instructions (group B) were further guided to use the Allerguard encasing for quilts and mattresses of all family members. We repeatedly examined Der p 1 + Der f 1 in the infants' mattresses and anti-Dermatophagoides farinae (Df) IgE in the infants' sera, and we performed skin prick tests with Df extract for 1 year. RESULTS: The mite-blocking encasing markedly reduced the levels of Der p 1 + Der f 1 (3.0 microg/g dust for group A vs 0.77 microg/g dust for B, p < 0.001). It also prevented the increase in serum levels of anti-Df IgE (2.5 U/ml for group A vs 0.7 U/ml for group B, p < 0.05) and positive reactions to skin prick testing with Df extract (63% for group A vs 31% for group B, p < 0.02) over 1 year. CONCLUSION: The bedding encasement with the mite-blocking fibers was effective for preventing atopic infants from being sensitized to HDMs, and it seems to be beneficial to modern busy housekeepers.

Allergens↗
PubMed1999

House dust mite avoidance for children with asthma in homes of low-income families.

BACKGROUND: Home exposure to high levels of house dust mite allergen has been shown to aggravate airways reactivity and asthma. OBJECTIVE: The purpose of this study was to determine whether specific house dust mite control measures could reduce exposure levels and asthma severity. METHODS: This double-blinded, randomized trial compared asthma progression over 1 year in children whose homes received standard environmental control intervention with those whose homes received aggressive intervention for dust mite elimination. The primary end point was doubling in PD20 methacholine. RESULTS: Symptom scores and quality-of-life scores were similar for the standard and aggressive intervention groups. PD20 methacholine doubling occurred in 9 members of the aggressive intervention group vs 4 control patients (P <.05). Dust mite levels decreased in the aggressive intervention homes compared with the standard intervention homes (P <.05). CONCLUSION: Aggressive dust mite intervention decreased dust mite levels and improved bronchial hyperresponsiveness.

Adolescent↗
PubMed1998

The epitope stability of group 1 and group 2 allergens in mite extracts.

BACKGROUND: Commercial mite allergenic extracts sold in the US are prepared with whole body mites in buffer solutions containing 50% glycerol. Mite extracts were reported to contain large number of proteolytic enzymes and their structural integrity in aqueous solutions have not been evaluated. OBJECTIVE: To evaluate the epitope stabilities of Group 1 and 2 allergens in two commercial mite extracts used by Center for Biologics Evaluation and Research (CBER) as reference extracts, E5-Dp (Dermatophagoides pteronyssinus) and E5-Df (D. farinae). METHODS: Epitope stability was determined by using monoclonal antibodies in a Sandwich ELISA. Samples were stored at four different temperatures and the amounts of Der p 1, Der p 2, Der f 1, and Der f 2 were determined at different time intervals. The overall stability of mite extracts was evaluated by immunoblot and competition ELISA. RESULTS: The epitope stability of these allergens varies: Der f 1 was stable for at least 3 years and Der f 2 for 1 year when stored at 4 degrees C; Der p 1 and 2 were less stable. None of the Group 1 and 2 allergens remained intact when stored at 50 degrees C. Immunoblot and competition ELISA data also showed similar trend of degradation as compared with extracts stored at 4 degrees C for same length of time. CONCLUSION: With the exception of Der f 1, the amount of detectable epitopes in Group 1 and 2 allergens reduce rapidly after 1 year, especially at elevated temperatures. The changes in allergen composition were also observed by immunoblotting and in relative potency by ELISA competition assay. These findings are highly relavent to the users of CBER's mite extracts as standards.

Allergens↗
PubMed1997

Dust mite allergen avoidance in the treatment of hospitalized children with asthma.

BACKGROUND: Asthma is a leading cause of hospital admission in children. The majority of children with asthma are sensitized and exposed to inhalant allergens that may contribute to chronic airway inflammation. OBJECTIVE: To evaluate the practicality and effects of dust mite (D. farinae and D. pteronyssinus) allergen avoidance in homes of children hospitalized with acute asthma. METHODS: Children 5 to 18 years of age who were admitted with asthma to a suburban Atlanta hospital were randomly assigned, without knowledge of allergen sensitization or exposure in their houses, to active (n = 13) or placebo (n = 10) treatment group. Active treatment included encasing mattress, box springs, and pillows in allergen impermeable covers; weekly hot water wash of bed linens; replacement of bedroom carpet with polished flooring; and 3% tannic acid spray to living room carpet. Placebo treatment included permeable encasing for bedding, cold water wash, and water spray for carpet. Dust samples were analyzed for dust mite, cockroach, and cat allergens, while serum samples were analyzed for IgE antibodies to the same allergens. Outcome measures included daily peak expiratory flow rates, spirometry, methacholine inhalation challenge, and hospital readmission. RESULTS: Children in both groups were similar by demographics, sensitization, and exposure to dust mite allergen. Allergen levels fell > 3-fold in many active and placebo homes. Children in the active group had improved PEFR at 3 and 6 months after intervention (P < .04, P < .05, respectively). Six of seven children in the study who were sensitized and exposed to dust mite allergen demonstrated improved PEFR at 3 months when allergen levels fell in both bedding and bedroom floor. There was no difference in FEV1 or methacholine challenge, although a few children in either group could tolerate methacholine because of bronchial hyperreactivity. Six children (four active and two placebo) were readmitted to hospital during the study. CONCLUSION: Increases in PEFR were recorded among children in the active treatment group and also among sensitized patients whose dust mite allergens fell. These results support the hypothesis that avoidance can be effective even among children admitted to hospital. The study was complicated by insufficient numbers of mite-allergic children and poor compliance with diaries and the protocol. Recruitment from the hospital resulted in participants with more severe asthma than anticipated. The results also suggest that many of the patients in this group will continue to have exacerbations triggered by upper or lower respiratory tract infections.

Adolescent↗
PubMed1990

Honey bee mortality due to tracheal mite parasitism.

We demonstrate, by truncating the expected negative binomial distribution, that the tracheal mite parasite, Acarapis woodi, causes mortality in the European honey bee, Apis mellifera, but, that this mortality can be documented only during periods of low mite densities (mites per bee). At high mite densities, this technique no longer reveals mite-induced mortality. We suggest that this paradox results from a reduction in the mortality threshold at high mite densities, concealing mortality from our truncation procedures. Longitudinal comparisons of hive and forager bee cohorts, nevertheless, suggests mortality at all levels of infestation. We propose that persistent parasitism overcomes a colony's ability to compensate for losses, leading to its sudden decline and death.

Animals↗
PubMed2000

Feeding life style of redlegged earth mite, Halotydeus destructor (Acari: Penthaleidae), in pastures and the role of broad-leafed weeds.

Redlegged earth mite, Halotydeus destructor, is a major pest of pastures and crops in Australia, and also feeds on lower plants on the soil surface. Feeding behaviour is reviewed, and the role of Arctotheca calendula, capeweed, in determining occurrence and abundance in pastures is investigated. Mites fed more and produced more progeny on Trifolium subterraneum (subclover) than on capeweed in non-choice experiments. In pastures with mixed species three times more mites were feeding on subclover than on capeweed foliage. However, twice as many mites were found on the soil surface under pasture patches consisting mainly of capeweed than of subclover. Patches were selected on the basis of pasture height, irrespective of plant composition. Twice as many mites were found in populations under patches of tall than short pasture. The daytime relative humidity was higher in tall than short patches, and the temperature slightly lower, making tall patches a more favourable niche for these mites. Ninety per cent of H. destructor were on the soil surface, while 10% were feeding on the upper canopy of pasture. The proportion of each population that was feeding was greater on subclover than capeweed, and subclover was a more suitable food. In Australia H. destructor occurs in regions with mixed pasture species, grown in rotation with grain crops. The ability of H. destructor to utilize foliage of a range of plant species of differing suitability for food, while living mostly on the soil surface in niches favourable for survival, has enabled it to become very abundant.

Animals↗
PubMed2001

How species-specific is the phoretic relationship between the broad mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), and its insect hosts?

Broad mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), is a serious plant pest in tropical and subtropical regions. Phoretic associations between broad mite and two genera of whiteflies (Insecta: Homoptera: Aleyrodidae). namely Bemisia and Trialeurodes, have been reported from different parts of the world. Our purpose was to determine the specificity of the association between the mite and its phoretic hosts. Two host plants, potatoes and cucumbers, were used to study these relationships in the laboratory. Insects frozen for 24 h were used as potential phoretic hosts in all experiments. Attachment levels were monitored by counting the number of mites attached to each insect. All tests were conducted for 4-6 h. as attachment to Bemisia tabaci on potato shoots leveled off after 4 h, increasing only marginally after 8 h. Attachment levels to thrips (the western flower thrips, Frankliniella occidentalis) and to allate aphids (Myzus persicae) was negligible relative to the attachment to B. tabaci. Broad mite also attached to the whiteflies Dialeurodes citri, Aleyrodes singularis and Trialeurodes lauri, the latter being the least attractive species (including B. tabaci). Washing B. tabaci with pentane greatly reduced attachment. Using cucumbers as hosts did not substantially change the general trend, but attachment levels were lower. The phoretic relationship between broad mite and its insect hosts appears to be specific to whiteflies, with some whiteflies having a higher potential as phoretic hosts.

Animals↗
PubMed2000

Contamination of passenger trains with Dermatophagoides (Acari: Pyroglyphidae) mite antigen in Japan.

Passenger trains were surveyed for contamination with Dermatophagoides farinae Hughes and Dermatophagoides pteronyssinus (Trouesart) mites in Japan. A total of 492 dust samples were collected from upholstered seats in six commuter trains, one long-distance express train and three night trains in October, 1996 and January, April, and July, 1997. Mite antigen levels contained in fine dust fractions of these samples were measured by an enzyme-linked immunosorbent assay. Most samples obtained from commuter trains showed relatively high mite antigen levels of > 10 microgm(-2) (corresponding to > 100 mites). Express and night trains showed lower antigen levels per square meter, but higher mite antigen levels per gram of fine dust than commuter trains, indicating relatively high mite antigen densities. Seasonal comparisons indicated that commuter trains showed the highest mean antigen level per square meter in winter (January), whereas the highest antigen level per gram of fine dust was observed in summer (July) in express and night trains.

Animals↗
PubMed2000

Phytophagous mite populations on Tahiti lime, Citrus latifolia, under induced drought conditions.

In the north-western region of Venezuela, Phyllocoptruta oleivora, Tetranychus mexicanus and Brevipalpus phoenicis are common plant-feeding mites on leaves, fruits and branches of Tahiti lime, Citrus latifolia. The population dynamics of these herbivores are affected by many factors, such as weekly treatments with wettable sulphur, particularly during the wet season, maintenance pruning of plants, irrigation with microsprinklers, induction of water stress by withholding irrigation and biotic and abiotic environmental factors. During October 1994-January 1995, 31 trees in a commercial orchard were sampled weekly in order to describe population fluctuations of plant-feeding mites (mean number of mites per leaf or fruit), before (4 weeks) and after (4 weeks) a period of 6 weeks of drought stress (no irrigation). The population density of P. oleivora increased progressively during the last 3 weeks of the irrigation period and reached a maximum of 24 mites per fruit. In contrast, the populations of the other two species, T. mexicanus and B. phoenicis, remained at the same low density as before the withholding-irrigation period. After 6 weeks without irrigation, only T. mexicanus increased, to a high mean value of 11 mites per leaf. The withholding-irrigation practice appears to affect the population size of P. oleivora towards the end of this period and that of T. mexicanus at the beginning of the re-establishment of the water supply. The highest proportion of trees (32%) was infested by T. mexicanus after the withholding-irrigation period, when irrigation was resumed, whereas the highest levels of infestation of trees by P. oleivora and B. phoenicis were 16 and 10%, respectively, during the last week of the water-stress period. Although factors affecting the dynamics of the mites in the orchard are likely to be complex, irrigation management apparently plays an important role.

Animals↗
PubMed2002

Detection of serine proteases in extracts of the domestic mite Blomia tropicalis.

Previous studies have shown that the domestic mites Dennatophagoides pteronyssinus and D. farinae contain allergens with serine protease activity. These proteolytic allergens include trypsin, chymotrypsin, elastase, kallikrein, and C3/C5 convertase. However, it is not known whether the domestic mite Blomia tropicalis shares with other mite species the serine protease activities. The enzymatic activity present in extracts obtained from food-free B. tropicalis was investigated using specific substrates and inhibitors. Based upon the concentration response and inhibition profiles, and the digestion of specific substrates our data demonstrate that extracts from B. tropicalis exhibit several serine-protease-like activities. The enzyme activities detected in the B. tropicalis extracts are trypsin, elastase, chymotrypsin, kallikrein, C3/C5 convertase, and mast cell protease. Our results also demonstrate that kallikrein and C3/C5 convertase-like activities were not significantly affected by the alpha1-antiprotease, a naturally occurring serine protease inhibitor which protects lung mucosa from the enzymatic action. These data strongly suggest that the Echymyopodidae mite B. tropicalis shares at least five serine proteases with members of other mite families, the Glycyphagidae and Pyroglyphidae. In addition, our data demonstrate the potential use of biochemical methods to detect serine proteases for evaluation of mite growth in viitro, or to detect environmental exposures to these enzymes.

Animals↗
PubMed2002

Soil oribatid mite communities under three species of legumes in an ultisol in Brazil.

Oribatid mite densities in the topsoil and their activity at the soil surface were monitored under three species of perennial legume cover crops namely, Arachis pintoi, Macroptilium atropupureum and Pueraria phaseoloides, grass (Panicum maximum) and bare plots on three occasions in 1998 and 1999 in a derived savanna zone in Brazil. Both densities and activity at the soil surface were higher in the early but cool dry season in April 1998 than in the early wet but warm season in November 1998 and 1999. Three taxonomic groups of macropyline oribatid mites, namely Nothrus, Archegozetes and Masthermannia as well as a brachypyline taxon, Scheloribates were suggested as possible indicators of effect of legumes on soil biota because their populations increased under the legumes and/or the irresidues. Nothrus in particular increased in abundance more than any other taxon in the presence of residues of A. pintoi. Each legume supported a unique oribatid mite community in terms of species composition and relative abundance. The large numbers of Archegozeres trapped from all the legume and grass plots in April and November 1998 were also attributed to highly conducive conditions provided by the vegetation cover and their residues. The results suggest that the oribatid mite community of the study area was numerically stable as the peak populations of different species were not synchronized. Many taxonomic groups of pycnonotic brachypyline mites were absent. Legume cover crops, especially A. pintoi, and their residues have potential in restoring oribatid mite populations to precultivation levels.

Animals↗
PubMed2003

Exudate from sporulating cultures of Hirsutella thompsonii inhibit oviposition by the two-spotted spider mite Tetranychus urticae.

The acaricidal mycopathogen Hirsutella thompsonii has been found to secrete metabolites that are active against female Tetranychus urticae. Specifically, the rose-colored exudate produced on sporulating cultures of Mexican HtM120I strain sterilized female spider mites in a dose-dependent fashion. Topical application of the exudate resulted in a 100% reduction in mite fecundity over the initial six days of experimentation. Depending upon the exudate dosage, mites partially recovered within 3 and 6 d post-treatment and produced a limited number of eggs. The spider mite active HtM120I exudate contained less detectable HtA toxin than the HtM120I broth filtrate, and it was innocuous when injected into the greater wax moth Galleria mellonella L. larvae. Broth filtrates of HtM120I cultures, although toxic to assayed G. mellonella larvae, did not inhibit mite oviposition to the degree or duration of the exudate preparations. These findings suggest that the factor responsible for suppressing oviposition in female spider mites is linked to the sporulation process and is distinct from the well-characterized HtA produced by vegetative cells.

Animals↗