Han, Jun; Choi, Byeoung-Ryeol; Lee, Sang-Gyeu; Kim, Soon Il; Ahn, Young-Joon
The toxicity of 10 plant essential oils to adults of acaricide-susceptible, chlorfenapyr-resistant (CRT-53), fenpropathrin-resistant (FRT-53), pyridaben-resistant (PRT-53), and abamectin-resistant (ART-53) strains of Tetranychus urticae Koch (Acari: Tetranychidae) and to female Neoseiulus californicus McGregor (Acari: Phytoseiidae) was examined using spray or vapor-phase mortality bioassays. In bioassay with the susceptible adults, lemon eucalyptus (19.3 microg/cm3) was the most toxic oil, followed by peppermint, citronella Java, thyme red, caraway seed, clove leaf, and pennyroyal oils (LC50, 20.6-23.7 microg/cm3). The toxicity of these oils was almost identical against adults from either of the susceptible and resistant strains, even though CRT-53, FRT-53, PRT-53, and ART-53 adults exhibited high levels of resistance to chlorfenapyr (resistance ratio [RR], > 9,140), fenpropathrin (RR, 94), pyridaben (RR, > 390), and abamectin (RR, 85), respectively. Against female N. californicus, lemon eucalyptus (LC50, 21.4 microg/cm3) was the most toxic oil, whereas the LC50 values of the other nine oils ranged from 23.2 to 72.6 microg/cm3. N. californicus was 1-2 times more tolerant than T. urticae to the test essential oils. Thus, these essential oils merit further study as potential acaricides for the control of acaricide-resistant T. urticae populations as fumigants.
Costello, Michael J
Sulfur is the oldest and most widely used fungicide in the vineyards of California, where it is used for control of powdery mildew (Uncinula necator [Schw.] Burr). For decades, sulfur use has been associated with outbreaks of Tetranychus pacificus McGregor (Acari: Tetranychidae) on cultivated grapes in the San Joaquin Valley. I undertook large-scale field studies to test this association, to evaluate the impact of sulfur on Galendromus occidentalis (Nesbit) (Acari: Phytoseiidae), a major predator of T. pacificus, and to determine if timing of sulfur applications with respect to grape bloom has an impact on T. pacificus density. The studies took place in a 32 ha vineyard in Fresno County, and all fungicide applications were made with commercial-scale equipment. In 1998 a 'high sulfur' treatment, a combination of wettable sulfur and sulfur dust, was compared to 'low sulfur,' in which demethylation inhibitor (DMI) fungicides partially substituted for sulfur. In 1999 treatments were 'sulfur,' 'DMI,' 'sulfur pre-bloom' (here sulfur was applied prior to grape bloom, in late May, and then DMIs were applied until mid-season) and 'sulfur post-bloom' (the reverse of 'sulfur pre-bloom'). In each year, the T. pacificus population increase came after the end of fungicide applications, and results clearly show a relationship between sulfur use and T. pacificus density. In 1998, mean T. pacificus density was 2.7 times higher and mean G. occidentalis density 2.5 times higher in 'high sulfur' compared to 'low sulfur.' In 1999, the highest T. pacificus counts were in the 'sulfur' and 'sulfur pre-bloom' treatments, 4.8 times higher than 'sulfur post-bloom' and 2 times higher than 'DMIs.' Density of G. occidentalis was 2.3 times as high in 'sulfur' or 'sulfur pre-bloom' than 'DMIs.' The predator/prey ratio was not significantly different among treatments in 1998, but in 1999 it was highest in the 'sulfur pre-bloom' treatment. In 1999, density of Homeopronematus anconai (Baker) (Acari
Badii, Mohammad H; Hernández-Ortiz, Emilio; Flores, Adriana E; Landeros, Jerónimo
The aims of this study were: (a) determine the prey stage preference of female Euseius hibisci (Chant) (Phytoseiidae) at constant densities of different stages of Tetranychus urticae Koch (Tetranychidae), (b) assess the functional response of the predator females to the varying densities of eggs, larvae, or protonymphs of T. urticae, and (c) estimate the functional response of E. hibisci when pollen of Ligustrum ovalifolium was present as well. We conducted experiments on excised pieces of strawberry leaf arenas (Fragaria ananassa) under laboratory conditions of 25+/-2 degrees C, 60+/-5% RH and 12 h photophase. Our results indicated that the predator consumed significantly more prey eggs than other prey stages. Consumption of prey deutonymphs and adults was so low that they were excluded from the non-choice functional response experiments. The functional response on all food items was of type II. The two parameters of the functional response were estimated for each prey type by means of the adjusted non-linear regression model. The highest estimated value a' (instantaneous rate of discovery) and the lowest value of Th (handling time, including digestion) were found for the predator feeding on prey eggs, and a' was lowest and Th highest when fed protonymphs. Using the jack-knife method, the values for the functional response parameters were estimated. The values of a' and Th produced by the model were similar among all prey types except for the eggs, which were different. Using pollen simultaneously with prey larvae decreased the consumption of the latter over the full range of prey densities The suitability of this predator for biological control of T. urticae on strawberry is discussed.
Liburd, O.E.; White, J.C.; Rhodes, E.M.; Browdy, A.A.
The residual effects of several reduced-risk and conventional miticides were evaluated in strawberries (Fragaria z ananassa Duchesne) on the twospotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae) and on 2 predatory mites, Neoseiulus californicus McGregor and Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). Experiments were conducted in the laboratory and greenhouse. The greenhouse experiments also tested the direct effects of the miticides on TSSM. The efficacy of conventional and reduced-risk miticides was evaluated on strawberry leaf discs and on whole plants for control of TSSM. Furthermore, the residual effects of these miticides were evaluated on whole strawberry plants against selective predatory mites. For TSSM, 5 treatments were evaluated: a conventional miticide; fenbutatin-oxide (Vendex[reg]) and 3 reduced-risk miticides; binfenazate (Acramite 50WP[reg]), activated garlic extract (Repel[reg]), sesame seed and castor oil (Wipeout[reg]), and a water-treated control. For predatory mites, the residual effects of only Acramite[reg] and Vendex[reg] were evaluated. Acramite[reg] was the most effective acaricide in reducing TSSM populations in both the laboratory and greenhouse experiments. Vendex[reg] and Wipeout[reg] were also effective in the laboratory, but did not cause significant reduction of TSSM in the greenhouse. Repel[reg] was the least effective of the 4 pesticides evaluated. Neither Acramite[reg] nor Vendex[reg] had a significant effect on either predatory mite species. However, there appeared to be more predatory mites on the Vendex[reg]-treated plants than on the Acramite[reg]-treated plants. There were significantly more predatory mites of both species on the cue plants, which were inoculated with TSSM versus the non-cue plants, which were not inoculated. (author) [Spanish] Los efectos residuales en poblaciones de la 'arana roja', Tetranychus urticae Koch (Acari: Tetranichidae) y de los acaros predadores
Negm, Mohamed W.; Alatawi, Fahad J.; Aldryhim, Yousif N.
The old world date mite, Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) is a severe spider mite pest of date palm in most of the Middle East and North Africa. Considering that nothing is known about the performance of phytoseiid predators against O. afrasiaticus, biology, predation, and life table parameters of Cydnoseius negevi (Swirski and Amitai) and Neoseiulus barkeri Hughes (Acari: Phytoseiidae), collected from date palm orchards, were studied under laboratory conditions (25, 35°C and 35 ± 10% RH) as a first step to understand their effectiveness against all mobile life stages of O. afrasiaticus. For both predators, oviposition period was significantly shorter at 35°C than at 25°C. The following parameters were obtained for C. negevi and N. barkeri at 25 and 35°C, respectively: female longevity, 31.8, 20.1, 35.7, 27.4 d; fecundity, 21.6, 38.0, 18.8, 34.8 eggs per female; oviposition period, 23.9, 13.7, 25.9, 18.1 d. Total predation of C. negevi and N. barkeri female was 246.0, 270.0, 227.6, 205.3 prey at 25 and 35°C, respectively. Rectal plugs were observed attached to the opisthosoma of some adult females of N. barkeri, which often cause the mite to stick to the surface. Life table parameters were estimated as net reproductive rate (R0) 10.44, 17.35, 10.19, 13.84, intrinsic rate of increase (rm) 0.14, 0.19, 0.13, 0.16 d−1, finite rate of increase (λ) 1.15, 1.21, 1.12, 1.17 d−1, generation time (T) 17.03, 15.17, 17.83, 16.61 d, doubling time (DT) 04.95, 03.64, 05.33, 04.33 d for C. negevi and N. barkeri at 25 and 35°C, respectively. The values of intrinsic rate of increase and net reproductive rate were higher in C. negevi than N. barkeri at both temperature regimes. Therefore, it could be concluded that C. negevi performance was better than N. barkeri against O. afrasiaticus and can be considered as a valuable addition to the existing methods for spider mites control. PMID:25368087
Queiroz, Maria Cristina Vitelli; Sato, Mario Eidi
Phytoseiulus macropilis Banks (Acari: Phytoseiidae) is an effective predator of Tetranychus urticae Koch (Acari: Tetranychidae). The objectives of this research were to study the stability of fenpropathrin resistance and the cross-resistance relationships with different pyrethroids, and also to evaluate the effect of synergists [piperonyl butoxide (PBO), diethyl maleate (DEM) and S,S,S-tributyl phosphorotrithioate (DEF)] on fenpropathrin resistant and susceptible strains of this predaceous mite. The stability of fenpropathrin resistance was studied under laboratory conditions, using P. macropilis populations with initial frequencies of 75 and 50% of resistant mites. The percentages of fenpropathrin resistant mites were evaluated monthly for a period of up to 12 months. A trend toward decreased resistance frequencies was observed only during the first 3-4 months. After this initial decrease, the fenpropathrin resistance was shown to be stable, maintaining constant resistance frequencies (around 30%) until the end of the evaluation period. Toxicity tests carried out using fenpropathrin resistant and susceptible strains of P. macropilis indicated strong positive cross-resistance between fenpropathrin and the pyrethroids bifenthrin and deltamethrin. Bioassays with the synergists DEM, DEF and PBO were also performed. The maximum synergism ratio (SR = LC50 without synergist/LC50 with synergist) detected for the three evaluated synergists (PBO, DEM, DEF) was 5.86 (for DEF), indicating low influence of enzyme detoxification processes in fenpropathrin resistance.
Stavrinides, Menelaos C; Daane, Kent M; Lampinen, Bruce D; Mills, Nicholas J
We evaluated the relationships between plant water status and leaf temperature, and between leaf temperature and spider mite (Acari: Tetranychidae) and predatory mite (Acari: Phytoseiidae) populations in eight vineyards in California in 2006 and 2007. Temperature of south-facing leaves increased significantly by 0.8°C for every 1.0°C increase in ambient air temperature, and by 5.3°C for every one MPa drop in leaf water potential. Peak population densities of Pacific spider mite, Tetranychus pacificus McGregor, increased significantly with increasing frequency of leaf temperatures above 31°C. In contrast, peak population densities of Willamette spider mite, Eotetranychus willamettei (McGregor), showed no relationship with the frequency of leaf temperatures above 31°C. This differential relationship between the two mite species and high leaf temperatures is consistent with their upper thresholds for development, which are 40°C for T. pacificus and 31°C for E. willamettei, as identified in a previous study. Predatory mite population densities showed no relationship with peak population densities of either spider mite species during the analysis period, but decreased with the frequency of leaf temperatures above 31°C. In addition, predatory mite population densities were significantly higher on south-facing than interior leaves after adjusting for the effect of leaf temperature. These results help to explain why outbreaks of T. pacificus occur in warmer or water-stressed vineyards, whereas E. willamettei develops higher populations in cooler or well-irrigated vineyards. In addition, these results suggest that regulated deficit irrigation should be implemented with caution, especially in those vineyards with a high risk of T. pacificus outbreaks.
Marafeli, P P; Reis, P R; Silveira, E C da; Souza-Pimentel, G C; de Toledo, M A
The predatory mite, Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) is one of the principal natural enemies of tetranychid mites in several countries, promoting efficient control of those mites in several food and ornamental crops. Pest attacks such as that of the spider mite, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), is one of the problems faced by farmers, especially in the greenhouse, due to the difficulty of its control with the use of chemicals because of the development of fast resistance making it hard to control it. The objective of this work was to study the life history of the predatory mite N. californicus as a contribution to its mass laboratory rearing, having castor bean plant [Ricinus communis L. (Euphorbiaceae)] pollen as food, for its subsequent use as a natural enemy of T. urticae on a cultivation of greenhouse rosebushes. The studies were carried out in the laboratory, at 25 ± 2°C of temperature, 70 ± 10% RH and a 14 hour photophase. The biological aspects and the fertility life table were appraised. Longevity of 32.9 days was verified for adult females and 40.4 days for males. The intrinsic rate of increase (rm) was 0.2 and the mean generation time (T) was 17.2 days. The population doubled every 4.1 days. The results obtained were similar to those in which the predatory mite N. californicus fed on T. urticae.
Opit, George P; Perret, Jamis; Holt, Kiffnie; Nechols, James R; Margolies, David C; Williams, Kimberly A
Efficacy, costs, and impact on crop salability of various biological and chemical control strategies for Tetranychus urticae Koch (Acari: Tetranychidae) were evaluated on mixed plantings of impatiens, Impatiens wallerana Hook.f (Ericales: Balsaminaceae), and ivy geranium, Pelargonium peltatum (1.) L'Hér. Ex Aiton (Geraniales: Geraniaceae), cultivars in commercial greenhouses. Chemical control consisting of the miticide bifenazate (Floramite) was compared with two biological control strategies using the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). Treatments were 1) a single, early application of bifenazate; 2) a single, early release of predatory mites at a 1:4 predator:pest ratio based on leaf samples to estimate pest density; 3) a weekly release of predatory mites at numbers based on the area covered by the crop; and 4) an untreated control. T. urticae populations were monitored for 3 wk after the earliest treatment. When plants were ready for market, their salability was estimated. Bifenazate and density-based P. persimilis treatments effectively reduced T. urticae numbers starting 1 wk after plants had been treated, whereas the scheduled, area-based P. persimilis treatment had little or no effect. The percentage of flats that could be sold at the highest market wholesale price ranged from 15 to 33%, 44 to 86%, 84 to 95%, and 92 to 100%, in the control, weekly area-based P. persimilis, bifenazate, and single density-based P. persimilis treatments, respectively. We have shown that in commercial greenhouse production of herbaceous ornamental bedding plants, estimating pest density to determine the appropriate number of predators to release is as effective and offers nearly the same economic benefit as prophylactic use of pesticides.
Vassiliou, Vassilis A; Kitsis, Pavlos
Five field and greenhouse populations of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), were collected from five different districts across the island of Cyprus, both in field and greenhouse crops, and tested to determine levels of resistance. Standard leaf-disk spray application bioassay procedures were used to determine the LC50s for five chemicals: abamectin, acrinathrin, fenazaquin, pirimiphos methyl, and bifenazate. Selection of these compounds was based on the widespread use by farmers as well as on the frequent control failures against T. urticae reported in the past. Resistance of T. urticae was detected to abamectin, acrinathrin, fenazaquin, and pirimiphos methyl. The resistance ratios were calculated relative to the German susceptible reference strain. The highest resistance ratios at LC50 value were recorded for abamectin in a greenhouse rose population (RR = 3822), followed by a field bean (RR = 1356) and field tomato population (RR = 1320). Significantly high resistance levels were also found for acrinathrin where the highest resistance ratios at LC50 were recorded in a field bean T. urticae population (RR = 903). For fenazaquin, the highest resistance levels were recorded in a field tomato population (RR = 310). Lower resistance levels were found for pirimiphos methyl (13.3 < RR < 77.4) in all populations. Low susceptibility of T. urticae was observed for bifenazate (2.7 < RR < 24.4) in all populations. These results suggest that at least the use of abamectin and acrinathrin should be avoided or minimized for the control of T. urticae populations in indoor and outdoor environments.
Auger, Philippe; Bonafos, Romain; Kreiter, Serge; Delorme, Robert
A field population of Typhlodromus pyri (Acari: Phytoseiidae) tolerant to mancozeb was selected in the laboratory. After 10 mancozeb selections the LC50 value for mancozeb was 73 times higher in the selected-10 strain compared to the standard susceptible strain. A genetic analysis using reciprocal crosses and backcrosses of female F1 progeny found no maternal effect. Resistance in the selected-10 strain was codominant in expression, dominance value was about -0.1. Backcrosses between F1 females and the susceptible strain indicate that the resistance to mancozeb could be principally conferred by a predominant gene, but additional factors would also be involved.
Ferragut, Francisco; Navia, Denise
Predatory phytoseiid mites have been intensively studied and surveyed in the last decades because of their economic importance as biocontrol agents of agricultural pests. However, many regions of the world remain unexplored and the diversity of the family worldwide is still fragmentary. Up to date no phytoseiid species have been collected in the southernmost part of the Earth down to latitude 45º S. In this study Phytoseiidae were sampled from native vegetation in southern Argentina and Chile in the regions of Patagonia and Tierra del Fuego Island. Thirteen species were collected, five of which were previously described and eight, Chileseius australis n. sp., Neoseiulus mapuche n. sp., Typhlodromips valdivianus n. sp., T. fissuratus n. sp., Amblyseius grandiporus n. sp., A. caliginosus n. sp., Typhlodromus (Anthoseius) anomalos n. sp. and Metaseiulus parabrevicollis n. sp. are proposed as new to science and are described and diagnosed.
Zeity, Mahran; Srinivasa, N; Gowda, C Chinnamade
Two species of Tetranychidae (Acari), Oligonychus neotylus sp. nov. from Zea mays and Pennisetum purpureum (Poaceae) and Tetranychus hirsutus sp. nov. from Gymnema sylvestre R. Br. (Apocynaceae) are described from Karnataka state, south India. Tetranychus bambusae Wang and Ma is recorded for the first time from India and re-described. Four other species are reported for the first time from India viz., Oligonychus coniferarum (McGregor), Oligonychus duncombei Meyer, Tetranychus marianae McGregor and Tetranychus okinawanus Ehara from Cupressus sp., an undetermined grass, Centrosema pubescens and Adenium obesum, respectively.
Sato, Mário Eidi; Da Silva, Marcos Zatti; De Souza Filho, Miguel Francisco; Matioli, André Luís; Raga, Adalton
The purpose of this study was to evaluate the performance of Neoseiulus californicus (McGregor) for the control of Tetranychus urticae Koch in commercial strawberry fields, under greenhouse conditions, in association or not with the use of acaricides. The N. californicus strain used in this study was tolerant or resistant to several pesticides. Three experiments were carried out in the State of São Paulo, Brazil. For the first experiment, the initial infestation of T. urticae was 87.1 active stages per leaflet. Two applications of propargite were made on the first and the 14th day of the experiment. Approximately 2 h after each propargite application, N. californicus was released at a rate of 3.0 and 1.9 adult mites per plant, respectively, for each application. The population of T. urticae decreased from 87.1 to 2.8 mites per leaflet in the first three weeks. After this period, the population of T. urticae was maintained at low levels (
Takano-Lee, M; Hoddle, Mark
Predatory behaviors of Neosieulus californicus (McGregor) and Galendromus helveolus (Chant) attacking Oligonychus perseae Tuttle, Baker and Abbatiello on avocado leaves were videotaped and analyzed. Behaviors were recorded for "fresh" predators that were used < or = 48 hr post receipt from a commercial insectary and "cold stored" predators that were maintained at 12 degrees C for approximately 14 days. Fresh and cold stored G. helveolus were observed to attack O. perseae only after invading webbed nests. Conversely. fresh and cold stored N. californicus employed three different modes of predatory attack: (1) intercepting and attacking migrant O. perseae outside of web nests: (2) attacking prey through nest webbing; or (3) invading and attacking O. perseae inside nests. Predatory efficacy of both N. californicus and G. helveolus was reduced following cold storage. as both species engaged in certain predatory behaviors less frequently in comparison to predators that were not stored at low temperatures. Our observed results for N. californicus and G. helveolus attacking O. perseae are interpreted in relation to the chaetotaxy hypothesis, which proposes that phytoseiid invasion efficiency and propensity of webbed nests is facilitated by dorsal setal lengths.
Park, Hong-Hyun; Shipp, Les; Buitenhuis, Rosemarije
Predation, development, and oviposition experiments were conducted to evaluate Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) as a potential biological control agent for tomato russet mite, Aculops lycopersici (Massee) (Acari: Eriophyidae), which can be a serious pest of greenhouse tomatoes. Results showed that A. swirskii attacked all developmental stages of A. lycopersici and had a type II functional response at the prey densities tested. The attack rate and handling time estimates from the random predator equation were 0.1289/h and 0.2320 h, respectively, indicating that A. swirskii can consume 103.4 individuals per day. Predation rates of A. swirskii on A. lycopersici in the presence of alternative food sources such as pollen, first-instar thrips, or whitefly eggs were 74, 56, and 76%, respectively, compared with the predation rate on A. lycopersici alone. A. swirskii successfully completed their life cycle on either A. lycopersici or cattail (Typha latifolia L.) pollen. At 25 degrees C and 70% RH, developmental time of female A. swirskii fed on A. lycopersici or on cattail pollen was 4.97 and 6.16 d, respectively. For the first 10 d after molting to the adult stage, A. swirskii fed on A. lycopersici had higher daily oviposition rate (2.0 eggs per day) than on pollen (1.5 eggs per day). From this laboratory study, it can be concluded that A. swirskii has promising traits as a predator against A. lycopersici and that their populations can be maintained using alternative food sources such as cattail pollen. We suggest that the effectiveness of A. swirskii against A. lycopersici under field conditions needs next to be investigated.
Noronha, A C S; Ferreira, C T; Tavares, E J M; Lima, D B
Some species of spider mites belonging to the Tetranychidae family are known to associate with oil palm (Elaeis guineensis Jacq. - Arecaceae). The occurrence of Tetranychus palmarum Flechtmann & Noronha (Acari, Tetranychidae) was verified on oil palm seedlings under greenhouse conditions in the State of Pará in Northern Brazil. Plants with colonies of T. palmarum presented yellowish spots on leaflets and leaves with chlorosis. The objective of this study was to access the biology and fertility life table of T. palmarum in E. guineensis leaves. The experiment was conducted under four constant temperatures, 22, 25, 28, and 31°C, at 70 ± 10% RH under a 12:12 LD photoperiod. The duration of the egg-to-adult period was 18.4 and 9.8 days, at 22 and 31°C, respectively. The parameters of the fertility life table showed that 28°C is most suitable for the development and reproduction of T. palmarum, with higher values for reproductive parameters (R o , r m , and λ) and lower values for duplicating the population (TD). Therefore, it is apparent that the best temperature conditions for the development of T. palmarum are found in the warmer regions of Brazil, such as those observed in northern Brazil.
Alinejad, Marzieh; Kheradmand, Katayoon; Fathipour, Yaghoub
Knowledge of the impact of acaricides on predatory mites is crucial for integrated pest management programs. The present study evaluated the sublethal effect of fenazaquin (Pride(®) 20 % SC, Behavar, Iran) on life table parameters of the subsequent generation of the predatory mite, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), fed on Tetranychus urticae Koch under laboratory conditions [26 ± 1 °C, 70 ± 3 % RH and 16:8 (L:D) h]. The sublethal concentrations including LC10, LC20 and LC30 were determined using a dose-effect assay. The total development time of both sexes enhanced with an increase in concentration. The oviposition period and total fecundity decreased in dose-dependent manner. The intrinsic rate of increase (r) and finite rate of increase (λ) significantly descended with concentration enhancing from LC10 to LC30, compared with the control. The net reproductive rate (R 0) ranged between 2.76 and 7.37 offspring. Overall, the results indicated that fenazaquin had negative effects on development and life table parameters of the subsequent generation of A. swirskii. In conclusion, fenazaquin is not a compatible acaricide with A. swirskii and should not be used with this predatory mite in integrated management of T. urticae.
Szabó, Árpád; Pénzes, Béla; Sipos, Péter; Hegyi, Tamás; Hajdú, Zsuzsanna; Markó, Viktor
We examined the faunal composition and abundance of phytoseiid mites (Acari: Phytoseiidae) in apple orchards under different pest management systems in Hungary. A total of 30 apple orchards were surveyed, including abandoned and organic orchards and orchards where integrated pest management (IPM) or broad spectrum insecticides (conventional pest management) were applied. A total of 18 phytoseiid species were found in the canopy of apple trees. Species richness was greatest in the organic orchards (mean: 3.3 species/400 leaves) and the least in the conventional orchards (1.4), with IPM (2.1) and abandoned (2.7) orchards showing intermediate values. The phytoseiid community's Rényi diversity displayed a similar pattern. However, the total phytoseiid abundance in the orchards with different pest management systems did not differ, with abundance varying between 1.8 and 2.6 phytoseiids/10 leaves. Amblyseius andersoni, Euseius finlandicus, and Typhlodromus pyri were the three most common species. The relative abundance of A. andersoni increased with the pesticide load of the orchards whereas the relative abundance of E. finlandicus decreased. The abundance of T. pyri did not change in the apple orchards under different pest management strategies; regardless of the type of applied treatment, they only displayed greater abundance in five of the orchards. The remaining 15 phytoseiid species only occurred in small numbers, mostly from the abandoned and organic orchards. We identified a negative correlation between the abundance of T. pyri and the other phytoseiids in the abandoned and organic orchards. However, we did not find any similar link between the abundance of A. andersoni and E. finlandicus.
Twospotted spider mite, Tetranychus urticae Koch (Acari:Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera:Aphidiae), are the most important arthropod pests of hop (Humulus lupulus L.) in the Northern Hemisphere. A potential barrier for greater adoption of conservation biological c...
Evaluation of corn plant as potential banker plant for supporting predatory gall Midge, Feltiella acarisuga (Diptera: Cecidomyiidae) against Tetranychus urticae (Acari: Tetranychidae) in greenhouse vegetable production
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important and highly polyphagous pests of vegetables and other crops worldwide. In this study, several experiments were conducted under laboratory and greenhouse conditions to evaluate whether corn plant ...
da Silva, Marcos Zatti; Sato, Mário Eidi; de Oliveira, Carlos Amadeu Leite; Nicastro, Roberto Lomba
Brevipalpus phoenicis (Geijskes) is associated with the transmission of Citrus leprosis which is considered the main viral disease for the Brazilian citrus production. Mites of the families Stigmaeidae and Phytoseiidae coexist in various agricultural crops, often promoting the biological control of pest mites. The aim of this work was to study the interactions of Neoseiulus californicus (McGregor) (Phytoseiidae) and Agistemus brasiliensis Matioli, Ueckermann & Oliveira (Stigmaeidae), in the presence or absence of B. phoenicis. Two experiments were carried out. In the first, a N. californicus female was placed in each leaf disc arena, with eggs of B. phoenicis and A. brasiliensis as food sources. In the second, an A. brasiliensis female was placed in each arena, with eggs of B. phoenicis and N. californicus as food sources. Adults of both predators were able to consume both types of eggs available as food sources, but they fed on considerably higher proportions of B. phoenicis than on eggs of the predator. Eggs of A. brasiliensis were not a suitable food source for N. californicus, which produced only 0.1 egg per female per day when only eggs of that species were present in the experimental unit. The results suggest that eggs of N. californicus were a suitable food source for A. brasiliensis, which oviposited 1.12 eggs per day, when only eggs of N. californicus were provided to the stigmaeid mite. The possible interactions among N. californicus, A. brasiliensis and B. phoenicis in citrus orchards are discussed.
Yuan, Ming-Long; Wei, Dan-Dan; Wang, Bao-Jun; Dou, Wei; Wang, Jin-Jun
The family Tetranychidae (Chelicerata: Acari) includes ~1200 species, many of which are of agronomic importance. To date, mitochondrial genomes of only two Tetranychidae species have been sequenced, and it has been found that these two mitochondrial genomes are characterized by many unusual features in genome organization and structure such as gene order and nucleotide frequency. The scarcity of available sequence data has greatly impeded evolutionary studies in Acari (mites and ticks). Information on Tetranychidae mitochondrial genomes is quite important for phylogenetic evaluation and population genetics, as well as the molecular evolution of functional genes such as acaricide-resistance genes. In this study, we sequenced the complete mitochondrial genome of Panonychus citri (Family Tetranychidae), a worldwide citrus pest, and provide a comparison to other Acari. The mitochondrial genome of P. citri is a typical circular molecule of 13,077 bp, and contains the complete set of 37 genes that are usually found in metazoans. This is the smallest mitochondrial genome within all sequenced Acari and other Chelicerata, primarily due to the significant size reduction of protein coding genes (PCGs), a large rRNA gene, and the A + T-rich region. The mitochondrial gene order for P. citri is the same as those for P. ulmi and Tetranychus urticae, but distinctly different from other Acari by a series of gene translocations and/or inversions. The majority of the P. citri mitochondrial genome has a high A + T content (85.28%), which is also reflected by AT-rich codons being used more frequently, but exhibits a positive GC-skew (0.03). The Acari mitochondrial nad1 exhibits a faster amino acid substitution rate than other genes, and the variation of nucleotide substitution patterns of PCGs is significantly correlated with the G + C content. Most tRNA genes of P. citri are extremely truncated and atypical (44-65, 54.1 ± 4.1 bp), lacking either the T- or D-arm, as found in P. ulmi
Chueca, Patricia; Garcerá, Cruz; Moltó, Enrique; Jacas, Josep A; Urbaneja, Alberto; Pina, Tatiana
Petroleum-derived spray oils (PDSOs) offer an interesting alternative to acaricides to control the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), a key pest of clementine mandarins, Citrus reticulata Blanco. However, there is a lack of knowledge on how these products should be used. In this study, we evaluated the efficacy of four PDSOs (Sunspray Ultrafine, Volck Miscible, Texaco D-C-Tron Plus, and Agroaceite) at five concentrations (0.5, 1.0, 1.5, 2.0, and 3.0%) against eggs, protonymphs, and adults of T. urticae. We also characterized the PDSOs deposition pattern to find out the possible relationship between this factor and efficacy. In general, for all PDSO assayed, the higher the concentration, the higher the coverage, the mean area of impacts and efficacy on T. urticae. The biggest mean area of the impacts corresponded to Texaco D-C-Tron Plus. This PDSO was the most effective one and its efficacy was independent of concentration for concentrations higher than 1.0%. The same applied for concentrations higher than 1.5-2.0% for Agroaceite, Volck Miscible, and Sunspray Ultrafine, with high efficacies against eggs, protonymphs, and adults. PDSOs are highly effective against T. urticae, the use of these products should be encouraged in integrated citrus pest management programs in Spain. The next step will be to ascertain the efficacy under real field conditions.
Kim, Young-Joon; Park, Hyung-Man; Cho, Jum-Rae; Ahn, Young-Joon
A field colony of Tetranychus urticae (Koch) (Acari: Tetranychidae) resistant to pyridaben was selected with pyridaben successively for 20 generations to produce the PR-20 strain. Resistance and multiple resistance levels of the PR-20 strain to 15 acaricides were determined using a spray bioassay. The PR-20 strain was extremely resistant to pyridaben (resistance ratio [RR] = 240]. The strain exhibited extremely strong resistance to fenpyroximate (RR=373) and acrinathrin (RR=329) and strong resistance to benzoximate (RR=84). An RR = 10-40 was observed with abamectin, fenazaquin, fenbutatin oxide, fenpropathrin, and tebufenpyrad. The PR-20 strain showed low levels of resistance (RR <10) to azocyclotin, bromopropylate, chlorfenapyr, dicofol, milbemectin, and propargite. Synergist experiments with different metabolic inhibitors revealed that piperonyl butoxide (PBO), a mixed function oxidase (MFO) inhibitor, had the greatest effect on pyridaben resistance. PBO significantly caused pyridaben resistance in the PR-20 strain to drop to the full susceptibility level of the susceptible (S) strain. However, there was no significant difference in MFO activities measured using a model substrate between the S and PR-20 strains. These results suggest that use of certain acaricides with little multiple resistance or PBO will be useful for the management of pyridaben resistance in the field.
Ghazy, Noureldin Abuelfadl; Suzuki, Takeshi
We investigated the effects of changes in vapor pressure deficit (VPD) on the survival of diapausing (winter form) and non-diapausing (summer form) spider mites Tetranychus urticae Koch and Tetranychus kanzawai Kishida (Acari: Tetranychidae). Adult females of both species were kept without food at VPDs of 0.0, 0.4, 0.7, 1.5, 1.9, or 2.7 kPa for 3, 6, 9, 12, or 15 days at 25 °C. Diapausing females of both species kept at a VPD of ≥0.4 kPa for ≥6 days clearly tolerated desiccation. Under water-saturated conditions (VPD = 0.0 kPa), in which no desiccation occurred, diapausing females showed high starvation tolerance: 90 % survived for up to 15 days. No interspecific differences in tolerance to desiccation or starvation were observed under most conditions. These results indicate that diapause functions increase tolerance to desiccation and starvation. Such multiple tolerances to harsh environments might support winter survival in spider mites.
Efficacy of indigenous predatory mites (Acari: Phytoseiidae) against the citrus rust mite Phyllocoptruta oleivora (Acari: Eriophyidae): augmentation and conservation biological control in Israeli citrus orchards.
Maoz, Yonatan; Gal, Shira; Argov, Yael; Domeratzky, Sylvie; Melamed, Eti; Gan-Mor, Samuel; Coll, Moshe; Palevsky, Eric
The citrus rust mite (CRM), Phyllocoptruta oleivora (Acari: Eriophyidae) is a cosmopolitan key pest of citrus, inflicting severe economic damage if not controlled. In Israel, CRM damages all citrus cultivars. International regulation and increasing control failures of CRM led growers to seek sustainable biological control solutions such as acarine biological control agents. Laboratory studies conducted in Israel have indicated that the indigenous predator species Amblyseius swirskii, Iphiseius degenerans, Typhlodromus athiasae and Euseius scutalis (all Acari: Phytoseiidae) can potentially control CRM. Our general objective in the present study was to bridge the gap of knowledge between laboratory studies and the lack of control efficacy of these species in commercial orchards. Predator augmentation in the field showed that although predator populations increased immediately following releases they later decreased and did not affect CRM populations. When A. swirskii augmentation was combined with a series of maize pollen applications, A. swirskii populations were enhanced substantially and continuously but again CRM populations were not affected. Growth chamber studies with CRM-infested seedlings, with or without a maize pollen supplement, indicated that pollen provisioning led to population increase of E. scutalis and A. swirskii but only E. scutalis significantly lowered CRM populations. Control with E. scutalis was confirmed in the field on CRM infested seedlings with pollen provisioned by adjacent flowering Rhodes grass. While experiments in mature citrus orchard showed that pollen supplement usually increased predator populations they also indicated that other factors such as intraguild interactions and pesticide treatments should be taken into account when devising CRM biological control programs.
Lopez, L.; Smith, H. A.; Hoy, M. A.; Cave, R. D.
Amblyseius swirskiiAthias-Henriot (Acari: Phytoseiidae) is a predatory mite used to control thrips (Thysanoptera), whiteflies (Bemisia tabaci Genn., Hemiptera: Aleyrodidae), and broad mites (BMs) (Polyphagotarsonemus latus Banks, Acari: Tarsonemidae). Dispersal of A. swirskii, using the ornamental pepper “Explosive Ember” as a banker plant was evaluated for control of BMs in high-tunnel peppers. Open-canopy plants (5 weeks old) versus closed-canopy plants (10-weeks old) were used to evaluate the effect of plant connectedness in A. swirskii dispersal, in the presence (two females per plant) and absence of BMs. Plots consisted of a single central banker plant and four bell peppers extending linearly north and south. Sets of all treatments were destructively sampled 1, 4, and 7 days after releasing A. swirskii. Within 24 h, A. swirskii dispersed four plants away from the banker plants (1 m), regardless of the state of the canopy. Canopy connectedness did increase the presence of A. swirskii on the crop plants. Predatory mite numbers on closed-canopy treatments doubled within the 7-day sampling period, whereas no significant increase was observed on open-canopy treatments. The presence of BMs had no significant effect on the movement of A. swirskii. The results suggest further experiments with A. swirskii and banker plants for control of BMs is warranted. PMID:28025305
Carrillo, Daniel; Peña, Jorge E; Hoy, Marjorie A; Frank, J Howard
The red palm mite, Raoiella indica (Acari: Tenuipalpidae), is an important pest of palms (Arecaceae) and other species within the Zingiberaceae, Musaceae and Strelitziaceae families. Raoiella indica was discovered in the USA (Palm Beach and Broward counties, Florida) late in 2007, and it subsequently spread to other Florida counties. The predatory mite Amblyseius largoensis (Acari: Phytoseiidae) has been found associated with R. indica in Florida. In order to verify whether A. largoensis can develop and reproduce when feeding exclusively on R. indica, the biology of this predator was evaluated on various food sources, including R. indica. Five diets [R. indica, Tetranychus gloveri Aonidiella orientalis, Nipaecocus nipae, oak (Quercus virginiana) pollen] and a no-food control were tested to determine the predators' development, survivorship, oviposition rate, sex ratio and longevity at 26.5 +/- 1 degrees C, 70 +/- 5% RH and a 12:12 L:D photophase. Amblyseius largoensis was able to complete its life cycle and reproduce when fed exclusively on R. indica. The development of immature stages of A. largoensis was faster and fecundity and survivorship were higher when fed on R. indica or T. gloveri compared to the other food sources. The intrinsic rate of natural increase of A. largoensis was significantly higher when fed on R. indica than on other diets. These results suggest that, despite earlier assessments, A. largoensis can play a role in controlling R. indica.
Silva, E A; Reis, P R; Carvalho, T M B; Altoé, B F
Gerbera (Gerbera jamesonii Bolus and Hook,) is an ornamental Asteraceae of great commercial value, and pests can affect adversely its cultivation. More than 20 species of arthropods cause economic damage on gerbera, among them the two spotted mite, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), considered a key pest for this and other ornamental plants. In this work, some life-cycle aspects of T. urticae on gerbera, considered important for the knowledge of its population dynamics and for pest management programs, were studied. Mites were reared on 3-cm diameter arenas of gerbera leaf discs maintained on distilled water in Petri dishes, under laboratory conditions of 25 masculineC, 70 +/- 10% RU and 14-hour photophase, with only one egg left per arena, in a total of 262 arenas. Egg viability was 96.5% and 97.1% for unmated and mated females, respectively. Unmated females originated larvae which lived for 3.2 days and the stages of protonymph and deutonymph, 1.9 and 1.6 days, respectively; those from mated females lived 3.5 days and for protonymphs and deutonymphs, 2.0 and 1.6 days, respectively. Except for the duration of one generation (T), with similar values, 18.6 and 19.7 days, respectively for unmated and mated females, the net reproductive rate of increase (R masculine), the innate capacity to increase in number (r m) and the finite rate of growth (lambda) were different for mated and unmated females, respectively 11.5 and 24.6 for R0; 0.12 and 0.17 for r m and 1.13 and 1.19 for lambda.
Ben-David, Tselila; Gerson, Uri; Morin, Shai
Tetranychus turkestani Ugarov and Nikolskii and Tetranychus urticae Koch RF (red form) (Acari: Tetranychidae) are closely related species. Previously, the two species were found in separate agricultural habitats in Israel. Here, additional collections were undertaken and mixed populations of the two species were found. Manipulation experiments were conducted in order to test whether sexual interactions occur when T. turkestani and T. urticae RF share the same host. Interspecific crosses showed that the two species are capable of producing viable F(1) females, but that these females are sterile as their F(2) eggs failed to hatch. This indicates a post-zygotic reproductive barrier, supporting the current placement of T. turkestani as a separate taxon. Mating behavior parameters revealed that males of both species courted virgin conspecific and heterospecific females at the same rate and readily tried to copulate with them. Female mate recognition seemed to be more reliable in T. turkestani than in T. urticae RF as the number of copulations was significantly higher and their duration significantly shorter in the T. turkestani interspecific (T. turkestani female x T. urticae RF male) as compared to the intraspecific crosses, a phenomenon not observed in T. urticae RF. In mixed cultures, a significant reduction in female production was observed for T. urticae RF but not for T. turkestani, suggesting an asymmetric reproductive interference effect in favor of T. turkestani. The long term outcome of this effect is yet to be determined since additional reproductive factors such as oviposition rate and progeny survival to adulthood may reduce the probability of demographic displacement of one species by the other in overlapping niches.
Villanueva, Raul T; Childers, Carl C
Development and reproduction of Iphiseiodes quadripilis (Banks) were evaluated on single food diets of pollen (Malephora crocea Jacquin [ice plant] or Quercus sp. [oak]), spider mites, [Eutetranychus banksi (McGregor) or Panonychus citri (McGregor) (Acari: Tetranychidae)], or the citrus rust mite Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae). Experiments were conducted in an environmental chamber at 28 degrees +/- 1 degrees C, 14:10 (L:D) daylength, and 45% RH. I. quadripilis completed development and laid viable eggs that subsequently hatched on diets of either ice plant or oak pollen or eggs and motile stages of E. banksi. P. citri was acceptable as prey, but survival of larvae to adults was only 36%, whereas survival on E. banksi, ice plant pollen, and oak pollen was 48, 60, and 68%, respectively. The webbing produced by P. citri seemed to inhibit foraging behavior of I. quadripilis larvae and nymphs. Larvae of I. quadripilis developed only to the second nymphal instar on a diet of P. oleivora alone or water alone. Starved I. quadripilis females and deutonymphs were observed preying on the pink citrus rust mite, Aculops pelekassi (Keifer) (Eriophyidae). During 4-min observation trials, two series of I. quadripilis fed on 1.8 +/- 0.47 and 3.5 +/- 0.45 A. pelekassi motile stages after being starved for 6 and 24 h, respectively. I. quadripilis females did not prey on P. oleivora in arenas containing both rust mite species.
Rêgo, Adriano S; Teodoro, Adenir V; Maciel, Anilde G S; Sarmento, Renato A
The cassava green mite, Mononychellus tanajoa, is a key pest of cassava, Manihot esculenta Crantz (Euphorbiaceae), and it may be kept in check by naturally occurring predatory mites of the family Phytoseiidae. In addition to predatory mites, abiotic factors may also contribute to regulate pest mite populations in the field. Here, we evaluated the population densities of both M. tanajoa and the generalist predatory mite Euseius ho DeLeon (Acari: Phytoseiidae) over the cultivation cycle (11 months) of cassava in four study sites located around the city of Miranda do Norte, Maranhão, Brazil. The abiotic variables rainfall, temperature and relative humidity were also recorded throughout the cultivation cycle of cassava. We determined the relative importance of biotic (density of E. ho) and abiotic (rainfall, temperature and relative humidity) factors to the density of M. tanajoa. The density of M. tanajoa increased whereas the density of E. ho remained constant throughout time. A hierarchical partitioning analysis revealed that most of the variance for the density of M. tanajoa was explained by rainfall and relative humidity followed by E. ho density and temperature. We conclude that abiotic factors, especially rainfall, were the main mechanisms driving M. tanajoa densities.
Cargnus, Elena; Zandigiacomo, Pietro
The immature stages of four species of Kampimodromus Nesbitt (Acari: Phytoseiidae) from Italy and Croatia have been studied and identified both at stage and species level. Larval stages of Kampimodromus corylosus Kolodochka and all immature stages of Kampimodromus ericinus Ragusa di Chiara & Tsolakis and Kampimodromus langei Wainstein & Arutunjan are described for the first time. The relative length of the posterior dorsal setae Z4 make the larvae of Kampimodromus aberrans (Oudemans) easy to separate from those of the other three species. Nymphs of each species had similar diagnostics to the adults of the respective species. Ontogeny of the idiosomal and leg setation of the Kampimodromus immatures studied in comparison to the available data from immatures of other phytoseiid species is discussed. The length of seta Z4 in the K. aberrans larva, and the number of setae on leg IV of the deutonymphs of the four Kampimodromus species, are proposed as additional taxonomic traits for Phytoseiidae.
Costa, A F; Teodoro, P E; Bhering, L L; Fornazier, M J; Andrade, J S; Martins, D S; Zanuncio Junior, J S
Tetranychus urticae Koch (Acari: Tetranychidae) is considered the main pest of strawberry. Several factors can favor its development, among them the genotype susceptibility and cropping system. The aims of this study were to evaluate the agronomic performance of strawberry cultivars under different managements and to identify strawberry cultivars that meet tolerance to T. urticae and high fruit yield. Thirteen cultivars of strawberry ('Albion', 'Aleluia', 'Aromas', 'Camarosa', 'Camino Real', 'Campinas', 'Diamante', 'Dover', 'Festival', 'Seascape', 'Toyonoka', 'Tudla', and 'Ventana') under three managements (open field, low tunnel, and high tunnel) were evaluated. The T. urticae attack to different cultivars was influenced by managements, being low tunnel the one that provided higher infestations in the most evaluated cultivars. 'Camarosa' was the cultivar with the lower incidence of pest and 'Dover' had the higher infestation. The genotype most suitable for growing under different managements is the 'Festival' genotype, since it meets tolerance to T. urticae, high fruit yield, and phenotypic stability.
Pérez-Sayas, Consuelo; Aguilar-Fenollosa, Ernestina; Hurtado, Mónica A; Jaques, Josep A; Pina, Tatiana
Predatory mites of the Phytoseiidae family are considered one of the most important groups of natural enemies used in biological control. The behavioral patterns of arthropods can differ greatly daily and seasonally; however, there is a lack of literature related to Phytoseiidae diel and seasonal predation patterns. The predatory activity of three phytoseiid species (two Tetranychidae-specialists, Phytoseiulus persimilis and Neoseiulus californicus, and one omnivore, Euseius stipulatus) that occur naturally in Spanish citrus orchards was observed under laboratory conditions in winter and summer. The temperature and photoperiod of the climatic chamber where the mites were reared did not change during the experiment. Our study demonstrates that phytoseiids can exhibit diel and seasonal predatory patterns when feeding on Tetranychus urticae (Acari: Tetranychidae). Neoseiulus californicus was revealed to be a nocturnal predator in summer but diurnal in winter. In contrast, P. persimilis activity was maximal during the daytime, and E. stipulatus showed no clear daily predation patterns. The predatory patterns described in this study should be taken into account when designing laboratory studies and also in field samplings, especially when applying molecular techniques to unveil trophic relationships. © 2017 Institute of Zoology, Chinese Academy of Sciences.
Huang, Jian Hua; Freed, Shoaib; Wang, Li Si; Qin, Wen Jing; Chen, Hong Fan; Qin, Hou Guo
Thrips tabaci Lindeman (Thysanoptera: Thripidae) is one of the most important pests of asparagus in China. In this study the effects of five constant temperatures (15, 20, 25, 30 and 35 °C) on the growth, survivorship and reproduction of Proprioseiopsis asetus (Chant) (Acari: Phytoseiidae) fed on T. tabaci was examined under laboratory conditions. Development time of immatures decreased with increasing temperature. The lower egg-to-adult developmental threshold (T 0) and thermal constant (K) of P. asetus were estimated at 15.2 °C and 75.8 degree days by means of a linear model. Fertilized females fed on T. tabaci produced offspring of both sexes, whereas the offspring sex ratio [♀/(♀ + ♂)] of P. asetus at 20-35 °C was female-biased (0.68-0.78) and not significantly influenced by temperature. Survivorship during immature development was significantly influenced by temperature, and was especially low at 15 °C. Pre- and post-oviposition periods of fertilized females shortened with the increase in temperature. The longest oviposition period was 20.4 days, at 25 °C, whereas at 15 °C the mites did not reproduce. Maximum average life time fecundity and mean daily fecundity was recorded at 25 and 35 °C, respectively; the intrinsic rate of increase ranged from 0.05 (20 °C) to 0.17 (35 °C). The results indicate the capability of P. asetus to develop and reproduce at a broad range of temperatures, especially above 25 °C, which can be used for better management of T. tabaci in asparagus.
Melo, José W da S; Domingos, Cleiton A; Gondim, Manoel G C; Moraes, Gilberto J de
Mites of the genus Euseius are generally considered specialist as pollen feeders. Euseius alatus DeLeon is one of the six species of phytoseiid mites most commonly found on coconut plants in northeast Brazil associated with Aceria guerreronis Keifer. Although the morphology of E. alatus does not favor the exploitation of the meristematic area of the fruit inhabited by A. guerreronis, the predator may have some role in the control of this eriophyid during the dispersion process. The objective of this work was to evaluate the development and reproduction of E. alatus on the following diets: A. guerreronis, Ricinus communis pollen (Euphorbiaceae), and Tetranychus urticae Koch (Tetranychidae) + R. communis pollen + honey solution 10%. Euseius alatus developed slightly faster and had slightly higher oviposition rate when feeding on the diet composed of T. urticae + pollen + honey. However, life table parameters were very similar on all diets, suggesting that E. alatus may contribute in reducing the population of A. guerreronis in the field.
Bu, Chunya; Li, Jinling; Wang, Xiao-Qin; Shi, Guanglu; Peng, Bo; Han, Jingyu; Gao, Pin; Wang, Younian
Tetranychus cinnabarinus (Acari: Tetranychidae) is a worldwide polyphagous agricultural pest that has the title of resistance champion among arthropods. We reported previously the identification of the acaricidal compound β-sitosterol from Mentha piperita and Inula japonica. However, the acaricidal mechanism of β-sitosterol is unclear. Due to the limited genetic research carried out, we de novo assembled the transcriptome of T. cinnabarinus using Illumina sequencing and conducted a differential expression analysis of control and β-sitosterol-treated mites. In total, we obtained >5.4 G high-quality bases for each sample with unprecedented sequencing depth and assembled them into 22,941 unigenes. We identified 617 xenobiotic metabolism-related genes involved in detoxification, binding, and transporting of xenobiotics. A highly expanded xenobiotic metabolic system was found in mites. T. cinnabarinus detoxification genes—including carboxyl/cholinesterase and ABC transporter class C—were upregulated after β-sitosterol treatment. Defense-related proteins, such as Toll-like receptor, legumain, and serine proteases, were also activated. Furthermore, other important genes—such as the chloride channel protein, cytochrome b, carboxypeptidase, peritrophic membrane chitin binding protein, and calphostin—may also play important roles in mites' response to β-sitosterol. Our results demonstrate that high-throughput-omics tool facilitates identification of xenobiotic metabolism-related genes and illustration of the acaricidal mechanisms of β-sitosterol. PMID:26078964
Yin, Wan-Dong; Qiu, Gui-Sheng; Yan, Wen-Tao; Sun, Li-Na; Zhang, Huai-Jiang; Ma, Chun-Sen; Adaobi, Uzokwe Pauline
To understand the influence of different apple varieties on the development and reproduction of the European red mite, Panonychus ulmi (Koch) (Acari: Tetranychidae), age-stage two-sex life tables of P. ulmi on 'Fuji,' 'Starkrimson Delicious,' 'Golden Delicious,' and 'Granny Smith' varieties were constructed under laboratory conditions at 23 +/- 1 degrees C, 75 +/- 5% relative humidity, and a photoperiod of 16:8 (L:D) h. Results showed that total development time of immature females was shorter on Fuji than on the other varieties, and this was because of its shorter egg duration. Immature survival of P. ulmi was 74.51-78.00% among four apple varieties, and no significant differences were found. The total fecundity per female was significantly higher on Golden Delicious (34.12 eggs per female) than that on Fuji (27.15 eggs per female), Starkrimson Delicious (25.15 eggs per female), and Granny Smith (20.62 eggs per female). Based on the intrinsic rate of population increase, Fuji and Golden Delicious were more suitable than Starkrimson Delicious and Granny Smith.
White, Jeffrey C; Liburd, Oscar E
The effects of soil moisture and temperature on the reproduction of twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), were examined in laboratory and field tests in strawberries, Fragaria x ananassa Duchesne, in Florida. Different soil moisture levels (low, moderate, and high) were compared to determine how soil moisture affects the reproduction and development of twospotted spider mite. In addition to soil moisture, different irrigation techniques (drip versus drip/overhead) were compared to determine their effects on twospotted spider mite reproduction as well as the incidence of angular leaf spot, Xanthomonas fragaria Kennedy & King disease. Similar studies were conducted to determine how different temperatures (18, 27, and 35 degrees C) affect the reproduction and development of twospotted spider mites. In the laboratory, low soil moisture as well as temperatures >27 degrees C promoted twospotted spider mite development. A similar trend was observed in a field study with low soil moisture promoting twospotted spider mite reproduction during the early season (11 November--8 December). Irrespective of moisture levels, a significantly higher incidence of X. fragaria was recorded in treatments with drip/overhead irrigation systems compared with drip irrigation. Implications for management of soil moisture levels are discussed with respect to the abundance of twospotted spider mite and X. fragaria in strawberries.
Zhang, Yan-Kai; Chen, Ya-Ting; Yang, Kun; Qiao, Ge-Xia; Hong, Xiao-Yue
Reproductive endosymbionts have been shown to have wide-ranging effects on many aspects of their hosts’ biology. A first step to understanding how these endosymbionts interact with their hosts is to determine their incidences. Here, we screened for four reproductive endosymbionts (Wolbachia, Cardinium, Spiroplasma and Rickettsia) in 28 populations of spider mites (Acari: Tetranychidae) representing 12 species. Each of the four endosymbionts were identified in at least some of the tested specimens, and their infection patterns showed variations at the species-level and population-level, suggesting their distributions can be correlated with both the phylogeny and ecology of the hosts. Co-infections of unrelated bacteria, especially double infections of Wolbachia and Cardinium within the same individuals were common. Spiroplasma and Rickettsia infections were specific to particular host species, respectively. Further, the evolutionary histories of these endosymbionts were inferred by comparing the phylogenies of them and their hosts. These findings can help to clarify the interactions between endosymbionts and arthropods. PMID:27291078
Miresmailli, Saber; Isman, Murray B
Efficacy of rosemary, Rosmarinus officinalis L., essential oil was assessed against twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), as well as effects on the tomato, Lycopersicum esculatum Mill., host plant and biocontrol agents. Laboratory bioassay results indicated that pure rosemary oil and EcoTrol (a rosemary oil-based pesticide) caused complete mortality of spider mites at concentrations that are not phytotoxic to the host plant. The predatory mite Phytoseiulus persimilis Athias-Henriot is less susceptible to rosemary oil and EcoTrol than twospotted spider mite both in the laboratory and the greenhouse. Rosemary oil repels spider mites and can affect oviposition behavior. Moreover, rosemary oil and rosemary oil-based pesticides are nonpersistent in the environment, and their lethal and sublethal effects fade within 1 or 2 d. EcoTrol is safe to tomato foliage, flowers, and fruit even at double the recommended label rate. A greenhouse trial indicated that a single application of EcoTrol at its recommended label rate could reduce a twospotted spider mite population by 52%. At that rate, EcoTrol did not cause any mortality in P. persimilis nor did it affect their eggs. In general, EcoTrol was found to be a suitable option for small-scale integrated pest management programs for controlling twospotted spider mites on greenhouse tomato plants.
Bayoumy, Mohamed H; Osman, Mohamed A; Michaud, J P
Physical plant characteristics can influence predator foraging and their behavioral responses to each other. This study examined the searching efficiency and functional response of adult female Stethorus gilvifrons Mulsant foraging for Tetranychus urticae Koch (Acari: Tetranychidae) on castor bean, common bean, and cucumber leaves. Experiments conducted on leaf discs in arenas for 12 h revealed a type II functional response for S. gilvifrons on all host plants. Per capita searching efficiency and killing power decreased with increasing predator density on all plants, but most notably on common bean, the plant with the highest prey consumption rates, due to greater mutual interference. Attack rates were highest on common bean and lowest on castor bean, whereas handling times were shortest on common bean and longest on cucumber, such that the daily predation rate was maximal on common bean. Host plant interacted with predator and prey densities to affect searching efficiency and functional response, the differences in mite consumption among host plants increasing with predator and prey densities. The waxy layers of castor bean leaves and high trichome counts of cucumber leaves appeared to reduce predator foraging efficiency. Thus, the efficacy of S. gilvifrons against T. urticae is likely to be greatest on plants such as Phaeseolus vulgaris L. that have relatively smooth leaves.
de Souza, Izabel Vieira; Sá Argolo, Poliane; Júnior, Manoel Guedes Correa Gondim; de Moraes, Gilberto José; Bittencourt, Maria Aparecida Leão; Oliveira, Anibal Ramadan
Abstract The cultivation of tropical fruit trees has grown considerably in the state of Bahia, northeastern Brazil. Some of these have been severely attacked by phytophagous mites, which are usually controlled by the use of chemical pesticides. However, there is today a growing interest for the adoption of less aggressive measures of pest control, as for example the use of predatory mites. Most of the plant-inhabiting predatory mites belong to the family Phytoseiidae. The objective of this paper is to report the phytoseiid species found in an intensive survey conducted on cultivated tropical fruit trees in fifteen localities of the southern coast of Bahia. Measurements of relevant morphological characters are provided for each species, to complement the understanding of the morphological variation of these species. Twenty-nine species of sixteen genera were identified. A key was elaborated to assist in the separation of these species. Fifteen species are reported for the first time in the state, raising to sixty-six the number of species of this family now known from Bahia. Seventy-two percent of the species collected belong to Amblyseiinae, followed by Typhlodrominae (21%) and Phytoseiinae (7%). The most diverse genus was Amblyseius. Amblyseius operculatus De Leon was the most frequent and abundant species. Studies should be conducted to evaluate the possible role of the most common predators as control agents of the phytophagous mites co-occurring with them. PMID:26668542
Van Pottelberge, S; Van Leeuwen, T; Nauen, R; Tirry, L
A Belgian field strain (MR-VP) of Tetranychus urticae (Koch) (Acari: Tetranychidae) exhibits different levels of resistance to four frequently used METI (mitochondrial electron transport inhibitor)-acaricides, i.e. tebufenpyrad, fenpyroximate, pyridaben and fenazaquin. Resistance factors for these compounds were 184, 1547, 5971 and 35, respectively. A 23.5-fold increase in 7-ethoxy-4-trifluoromethylcoumarin O-deethylation activity suggested that metabolic resistance through elevated levels of cytochrome P450 dependent monooxygenase-activity is a possible resistance mechanism.However, synergism studies with different metabolic inhibitors revealed some contrasting resistance mechanisms between the METI-acaricides. Tebufenpyrad resistance could only be synergized after pre-treatment with the monooxygenase inhibitor piperonyl butoxide (PBO), whereas pyridaben resistance was strongly synergized both by PBO and the esterase inhibitor S,S,S-tributylphosphorotrithioate (DEF). Resistance levels to fenpyroximate could neither be suppressed by PBO nor by DEF. Although METI-acaricides are structurally related, these findings probably reflect a different role of esterases and mono-oxygenases in metabolic detoxification between these compounds. The overall lack of synergism by diethylmaleate (DEM) suggests that glutathione-S-transferases are not an important factor in resistance to METIs.Reciprocal crosses between susceptible females and resistant males showed no maternal effect, and resistance to METI-acaricides was inherited generally as a dominant trait. Backcrosses with F1 females revealed striking differences in the mode of inheritance. Although resistance to fenpyroximate and pyridaben was under monogenic control, resistance to tebufenpyrad was under control of more than one gene.
Ferragut, Francisco; Garzón-Luque, Eva; Pekas, Apostolos
The tomato spider mite Tetranychus evansi Baker and Pritchard (Acari: Tetranychidae), is a worldwide pest of solanaceous crops that has recently invaded many parts of the world. In the present study we examined the ecological impact of its arrival in the Mediterranean region. The spider mite and phytoseiid mite assemblages in various crop and non-crop plants in three areas of Valencia (Spain) were studied a few months before and 10 years after the invasion of T. evansi. According to rarefaction analyses, the invasion of T. evansi did not affect neither the total number of species in the mite community examined (spider mite and phytoseiid species) nor the number of species when the two communities were examined separately. However, after the invasion, the absolute and relative abundance of the native Tetranychus species was significantly reduced. Before the invasion, T. urticae and T. turkestani were the most abundant spider mites, accounting for 62.9 and 22.8 % of the specimens. After the invasion, T. evansi became the most abundant species, representing 60 % of the total spider mites recorded, whereas the abundance of T. urticae was significantly reduced (23 %). This reduction took place principally on non-crop plants, where native species were replaced by the invader. Null model analyses provided evidence for competition structuring the spider mite community on non-crop plants after the invasion of T. evansi. Resistance to acaricides, the absence of efficient native natural enemies, manipulation of the plant defenses and the web type produced by T. evansi are discussed as possible causes for the competitive displacement.
Xia, Bin; Zou, Zhiwen; Li, Pengxin; Lin, Peng
The effect of five constant temperatures (16, 20, 24, 28 and 32°C) on the development, survival and reproduction of Neoseiulus barkeri Hughes fed on Aleuroglyphus ovatus Toupeau (Acari: Acaridae) was examined in the laboratory at 85% relative humidity. Development time of different immature stages decreased with increasing temperature, total egg-to-adult development time varied from 5.0 ± 0.13 to 17.5 ± 0.29 days. The lower thermal threshold for development was 9.7 ± 2.48°C and the thermal constant from egg to adult was 111.1 ± 12.34 degree-days. Pre- and post-oviposition period and female longevity all shortened as temperature increased. The longest oviposition period was observed at 24°C with 20.4 ± 1.13 days. At 20, 24, 28 and 32°C, mated females laid on average 0.7 ± 0.08, 1.5 ± 0.04, 1.6 ± 0.11 and 1.5 ± 0.11 eggs per day, respectively, but no eggs were laid at 16°C. Both the maximum fecundity (30.9 eggs per female) and the highest intrinsic rate of increase (r (m) = 0.166) were obtained at 28°C. The results of this study indicated that a mass rearing of N. barkeri with A. ovatus as prey is feasible at the appropriate temperature.
Tixier, Marie-Stéphane; Baldassar, Andrea; Duso, Carlo; Kreiter, Serge
The family Phytoseiidae includes many species of predators involved in the control of mite pests of crops all over the world. In European vineyards, these natural enemies play a key role in plant protection as their presence usually makes the use of acaricides unnecessary. Each species has its specific biological features. It is thus of great interest to identify the species reported on grape, Vitis vinifera. The present paper, based on a world database of the family Phytoseiidae and on an analysis of more than 250 publications, presents the 54 species of Phytoseiidae belonging to 15 genera reported on V. vinifera in Europe, and identification keys to species. Online versions of the key (dichotomous and polytomous) with illustrations are available at http://wwwl.montpellier.inra.fr/CBGP/phytoseiidae/sitewebvineyards2/index.htm. An analysis of the biogeographic distribution of these species and their prey has also been carried out. Most species reported on V. vinifera in Europe are rare; only five species are frequently observed: Kampimodromus aberrans, Typhlodromus (Typhlodromus) pyri, Typhlodromus (Typhlodromus) exhilaratus, Euseius finlandicus and Phytoseius finitimus. The 12 countries where Phytoseiidae have been reported from grapes have been unevenly surveyed, the most well-known faunas being from Italy, Greece and France. These species are reported to prey upon the main species of mite pests of grapes.
Expression analysis of Drosophila doublesex, transformer-2, intersex, fruitless-like, and vitellogenin homologs in the parahaploid predator Metaseiulus occidentalis (Chelicerata: Acari: Phytoseiidae).
Pomerantz, Aaron F; Hoy, Marjorie A
Characterization and expression analyses are essential to gain insight into sex-determination pathways in members of the Acari. Little is known about sex determination at the molecular level in the western orchard predatory mite Metaseiulus occidentalis (Arthropoda: Chelicerata: Arachnida: Acari: Phytoseiidae), a parahaploid species. In this study, eight genes previously identified as putative homologs to genes involved in the sex-determination pathway in Drosophila melanogaster were evaluated for sex-specific alternative splicing and sex-biased expression using reverse-transcriptase PCR and quantitative real-time PCR techniques, respectively. The homologs evaluated in M. occidentalis included two doublesex-like genes (Moccdsx1 and Moccdsx2), transformer-2 (Mocctra-2), intersex (Moccix), two fruitless-like genes (MoccBTB1 and MoccBTB2), as well as two vitellogenin-like genes (Moccvg1 and Moccvg2). Single transcripts of equal size were detected in males and females for Moccdsx1, Moccdsx2, Mocctra-2, Moccix, and MoccBTB2, suggesting that their pre-mRNAs do not undergo alternative splicing in a sex-specific manner. Three genes, Moccdsx1, Moccdsx2 and MoccBTB2, displayed male-biased expression relative to females. One gene, Moccix, displayed female-biased expression relative to males. Two genes, Mocctra-2 and MoccBTB1, did not display detectable differences in transcript abundance in males and females. Expression of Moccvg1 and Moccvg2 were detected in females only, and transcript levels were up-regulated in mated females relative to unmated females. To our knowledge, this represents the first attempt to elucidate expression patterns of putative sex-determination genes in an acarine. This study is an initial step towards understanding the sex-determination pathway in the parahaploid M. occidentalis.
Nuvoloni, Felipe Micali; Lofego, Antonio Carlos; Castro, Elizeu Barbosa; Feres, Reinaldo José Fazzio
The current study describes the results of a survey of Phytoseiidae mites conducted on a rubber tree plantation in the State of Bahia, Brazil. We present 22 species, two of which are new to science, Amblydromalus insolitus n. sp. Nuvoloni & Lofego, and Typhlodromips paramilus n. sp. Nuvoloni & Lofego, and three new records for this host are presented. The species composition was more related with the records of the northern Brazilian Region, than with that of Southeastern and Midwestern.
Typhlodromus pyri and Euseius finlandicus (Acari: Phytoseiidae) as potential biocontrol agents against spider mites (Acari: Tetranychidae) inhabiting willows: laboratory studies on predator development and reproduction on four diets.
Puchalska, Ewa K; Kozak, Marcin
Typhlodromus pyri Scheuten and Euseius finlandicus (Oudemans) are important predators of phytophagous mites. The present laboratory study aimed to determine whether both species can develop and reach maturity feeding on spider mites occurring on willows, i.e., Schizotetranychus schizopus (Zacher), Schizotetranychus garmani Pritchard & Baker, and Tetranychus urticae Koch, and on Brassica napus L. pollen. The predators' development, reproduction and demographic parameters were significantly affected by diet. The data suggest that rape pollen can be useful in mass rearing of E. finlandicus but is completely unsuitable as alternative food for T. pyri. Short development time and high values of population parameters achieved by T. pyri feeding on larvae and protonymphs of S. schizopus and by E. finlandicus feeding on juvenile stages of S. garmani indicate great suitability of these preys as food for the phytoseiids, and make both predatory species promising biocontrol agents in spider mite control on willows.
Greco, Nancy M; Sánchez, Norma E; Liljesthröm, Gerardo G
Neoseiulus californicus (McGregor) is a promising agent for successful Tetranychus urticae Koch control through conservation techniques, in strawberry crops in La Plata (Buenos Aires, Argentina). In prey-predator interaction, initial relative densities have an important effect on system dynamics. The economic threshold level (ETL) used for this pest in the present study was 50 active mites per leaflet. In our laboratory experiments, initial T. urticae to N. californicus ratio had a significant effect on the population abundance of T. urticae at a 7-day period. When pest/predator ratio was 5/1 (at initial pest densities from 5 to 15 females/leaflet) the final number of active T. urticae/leaflet was significantly lower than the ETL, while at 20 females/leaflet this number did not differ from the ETL. At 7.5/1 ratio, the final number of active T. urticae/leaflet, at initial pest densities from 5 to 15 females/leaflet, reached the ETL without surpassing it. At 10/1 and 15/1 ratios, pest densities exceeded the ETL only at 15 initial T. urticae/leaflet. Most greenhouse and field observations were consistent with the predictions of a graphical model based on experimental results. This predator was very effective in limiting pest densities at a 7-day period and within the range of pest-predator ratios and absolute densities used in this study. Conservation of N. californicus promoting favorable pest/predator ratios may result in early control of T. urticae.
Devine, G J; Barber, M; Denholm, I
A strain of Tetranychus urticae (Koch; Acari: Tetranychidae), collected from hops (Humulus humuli L; Cannabaceae) in England with a short history of tebufenpyrad use, exhibited resistance to four METI (mitochondrial electron transport inhibitor)-acaricides; tebufenpyrad, pyridaben, fenazaquin and fenpyroximate. Resistance factors for these compounds in a microimmersion assay were 46, 346, 168 and 77 respectively, and corresponded to those exhibited by a Japanese METI-acaricide-resistant reference strain. Levels of resistance remained stable without further selection, and selection with tebufenpyrad did not increase them. The UK strain was also resistant (c 6-fold) to bifenthrin. Crosses of homozygous, diploid females with hemizygous, haploid males showed that, in the UK strain, METI-acaricide resistance was paternally and maternally inherited, and was an incompletely dominant trait. Another tebufenpyrad-resistant strain from the UK, originating from a chrysanthemum nursery (Chrysanthemum foeniculaceum Giseke; Asteraceae) was collected eight months later at a site c 210 km distant from the first. These are the first published incidences of METI-acaricide resistance in Europe and implications for the future use of these compounds are discussed.
Ros, Vera I. D.; Fleming, Vicki M.; Feil, Edward J.; Breeuwer, Johannes A. J.
At least 20% of all arthropods and some nematode species are infected with intracellular bacteria of the genus Wolbachia. This highly diverse genus has been subdivided into eight “supergroups” (A to H) on the basis of nucleotide sequence data. Here, we report the discovery of a new Wolbachia supergroup recovered from the spider mite species Bryobia species V (Acari: Tetranychidae), based on the sequences of three protein-coding genes (ftsZ, gltA, and groEL) and the 16S rRNA gene. Other tetranychid mites possess supergroup B Wolbachia strains. The discovery of another Wolbachia supergroup expands the known diversity of Wolbachia and emphasizes the high variability of the genus. Our data also clarify the existing supergroup structure and highlight the use of multiple gene sequences for robust phylogenetic analysis. In addition to previous reports of recombination between the arthropod-infecting supergroups A and B, we provide evidence for recombination between the nematode-infecting supergroups C and D. Robust delineation of supergroups is essential for understanding the origin and spread of this common reproductive parasite and for unraveling mechanisms of host adaptation and manipulation across a wide range of hosts. PMID:19098217
Yorulmaz Salman, Sibel; Aydınlı, Fatma; Ay, Recep
Phytoseiulus persimilis of the family Phytoseiidae is an effective predatory mite species that is used to control pest mites. The LC50 and LC60 values of etoxazole were determined on P. persimilis using a leaf-disc method and spraying tower. A laboratory selection population designated ETO6 was found to have a 111.63-fold resistance to etoxazole following 6 selection cycles. This population developed low cross-resistance to spinosad, spiromesifen, acetamiprid, indoxacarb, chlorantraniliprole, milbemectin and moderate cross-resistance to deltamethrin. PBO, IBP and DEM synergised resistance 3.17-, 2.85- and 3.60-fold respectively. Crossing experiments revealed that etoxazole resistance in the ETO6 population was an intermediately dominant and polygenic. In addition, detoxifying enzyme activities were increased 2.71-fold for esterase, 3.09-fold for glutathione S-transferase (GST) and 2.76-fold for cytochrome P450 monooxygenase (P450) in the ETO6 population. Selection for etoxazole under laboratory conditions resulted in the development of etoxazole resistance in the predatory mite P. persimilis that are resistant to pesticides are considered valuable for use in resistance management programmes within integrated pest control strategies.
Lara, Jesús R; Saremi, Naseem T; Castillo, Martin J; Hoddle, Mark S
Oligonychus perseae (Acari: Tetranychidae) is an important foliar spider mite pest of 'Hass' avocados in several commercial production areas of the world. In California (USA), O. perseae densities in orchards can exceed more than 100 mites per leaf and this makes enumerative counting prohibitive for field sampling. In this study, partial enumerative mite counts along half a vein on an avocado leaf, an industry recommended practice known as the "half-vein method", was evaluated for accuracy using four data sets with a combined total of more than 485,913 motile O. perseae counted on 3849 leaves. Sampling simulations indicated that the half-vein method underestimated mite densities in a range of 15-60 %. This problem may adversely affect management of this pest in orchards and potentially compromise the results of field research requiring accurate mite density estimation. To address this limitation, four negative binomial regression models were fit to count data in an attempt to rescue the half-vein method for estimating mite densities. These models were incorporated into sampling plans and evaluated for their ability to estimate mite densities on whole leaves within 30-tree blocks of avocados. Model 3, a revised version of the original half-vein model, showed improvement in providing reliable estimates of O. perseae densities for making assessments of general leaf infestation densities across orchards in southern California. The implications of these results for customizing the revised half-vein method as a potential field sampling tool and for experimental research in avocado production in California are discussed.
de Castro, Thiago Rodrigues; Ausique, John Jairo Saldarriaga; Nunes, Daiane Heloisa; Ibanhes, Fernando Henrique; Delalibera Júnior, Italo
Genetically modified plants carrying Cry toxins of Bacillus thuringiensis (Bt) are widely used for pest control. Possible adverse effects as a result of the use of this control technique to non-target organisms is still a concern; however, few studies have addressed the effects of Bt crops on phytoseiid predatory mites. Phytoseiids are important for the natural control of phytophagous mites, but they can also feed on pollen, plant exudates, etc. Thus, phytoseiids may ingest Bt toxins through several pathways. In this paper, we evaluate the direct effect of Bt-toxins by feeding the predators on Bt cell suspensions, on solution of a Bt toxin and the tri-trophic effect by Bt expressed in transgenic plants. We present a method of conducting toxicological tests with Phytoseiidae which can be useful in studies of risk analysis of toxins to be expressed by genetically engineered plants. This method was used to evaluate the potential effect of ingestion of suspensions of Bt (1.25 × 10(8) spores/ml) and of purified protein Cry1Ia12 (0.006 mg/ml and 0.018 mg/ml) on Euseius concordis, a predatory mite that develops and reproduces best on pollen. The effects of genetically modified Bollgard(®) cotton, which carries the Cry1Ac protein, on Neoseiulus californicus, a selective predator that feeds more on spider mites than on pollen or insects, was determined by feeding them with Tetranychus urticae reared in Bollgard(®) cotton and on the non-transgenic isoline. When E. concordis was fed with suspension of Bt isolate derived from product Dipel(®) PM, no significant effects were detected. Similarly, Cry1Ia12 Bt toxin, at a concentration of 0.006 mg/ml, did not affect E. concordis. At a concentration of 0.018 mg/ml, however, the intake of this protein reduced the reproduction of E. concordis. There were no effects of Bollgard(®) cotton on the biological traits and on the predatory capacity of N. californicus. Results indicate that the Cry toxins of B. thuringiensis
Woods, J L; James, D G; Lee, J C; Walsh, D B; Gent, D H
The temporal development of biological control of arthropod pests in perennial cropping systems is largely unreported. In this study, the development of biological control of twospotted spider mite, Tetranychus urticae Koch, and hop aphid, Phorodon humuli (Schrank), in a new planting of hop in Oregon is described over a period of 9 yr (2005-2013). Both the abundance and diversity of natural enemies increased over time. Known predators of hop aphid (Coccinellidae and Anthocoridae) were present in all years; however, stable biological control of hop aphid was not achieved in most years and aphicides were required to suppress populations at commercially acceptable levels in 5 of 9 yr. Populations of aphidophagous coccinellids developed synchronously with hop aphid populations, and temporal correlations indicated these are the primary predatory insect associated with hop aphid regulation. However, sampling methods did not assess levels of aphid parasitoids and hyperparasitoids and their contribution to biological control was unquantified. Spider mite biological control was associated primarily with predatory mites (Phytoseiidae) and Stethorus spp. (Coccinellidae). The magnitude of temporal correlations of abundance of these predators with spider mites was found to be greatest on the same sampling dates and at lags of 7-14 d. Stable biological control of spider mites occurred after four field seasons, suppressing spider mites to levels similar to those commonly achieved with chemical control. A survey of 11 commercial hop yards in Oregon documented pest and natural enemy densities under commercial management practices over a period of 4 yr (2008-2011). Natural enemy abundance in commercial hop yards was similar to that of a 2- to 3-yr-old hop yard with limited disturbance. Whereas total reliance on biological control for hop aphid is unlikely to be successful, there appears to be unrealized potential for biological control of spider mites in commercial production
Pozzebon, Alberto; Duso, Carlo; Tirello, Paola; Ortiz, Paulina Bermudez
Knowledge of the impact of insecticides on Tetranychus urticae Koch and its predator Phytoseiulus persimilis Athias-Henriot is crucial for IPM. This study evaluates the effect of thiamethoxam on T. urticae and its predator by considering different routes of exposure (topical, residual and contaminated food exposures) and their combinations. Thiamethoxam effects on T. urticae were higher when residual and contaminated food exposures were considered. The total effect was higher than 90% where contaminated food exposure was involved. On P. persimilis, the total effect was higher in residual and contaminated prey exposures compared with topical exposure, and all combinations of routes of exposure attained a total effect higher than 90%. Thiamethoxam was found to be toxic to T. urticae and P. persimilis; however, the impact of the insecticide depended on the routes of exposure and their combinations. Lethal and sublethal effects occurred in residual and contaminated food exposures, while only sublethal effects occurred in topical exposure of predators and prey. The toxicity of thiamethoxam on prey and predator increased with the number of exposure routes involved. By limiting exposure to thiamethoxam to ingestion of contaminated food only, the impact of the pesticide was more favourable to P. persimilis than to its prey. Copyright © 2010 Society of Chemical Industry.
Tixier, Marie-Stephane; Allam, Latifa; Douin, Martial; Kreiter, Serge
The family Phytoseiidae includes more than 2,300 species distributed all over the world. However despite the huge numbers of faunistic surveys carried out for more than 60 years, the fauna of some countries and particular ecosystems remain little explored. This paper reports results of surveys carried out in various regions of Morocco (from Sahara to Atlantic and Mediteranean coasts) in 2002 and 2003. A total of 43 species was found. Among them 19 are new for the Moroccan fauna and five are new to science. This paper provides the descriptions of these five new species, Neoseiulus thymeleae, Transeius audeae, Typhlodromus (Typhlodromus) ballotae, T. (T.) leclanti, T. (T.) mazarii, and re-descriptions of two species (Typhlodromus (T.) setubali and Typhlodromus (Anthoseius) clairathiasae. A key to females of the 52 species now known from Morocco is given.
Molecular characterization and evolutionary insights into potential sex-determination genes in the western orchard predatory mite Metaseiulus occidentalis (Chelicerata: Arachnida: Acari: Phytoseiidae).
Pomerantz, Aaron F; Hoy, Marjorie A; Kawahara, Akito Y
Little is known about the process of sex determination at the molecular level in species belonging to the subclass Acari, a taxon of arachnids that contains mites and ticks. The recent sequencing of the transcriptome and genome of the western orchard predatory mite Metaseiulus occidentalis allows investigation of molecular mechanisms underlying the biological processes of sex determination in this predator of phytophagous pest mites. We identified four doublesex-and-mab-3-related transcription factor (dmrt) genes, one transformer-2 gene, one intersex gene, and two fruitless-like genes in M. occidentalis. Phylogenetic analyses were conducted to infer the molecular relationships to sequences from species of arthropods, including insects, crustaceans, acarines, and a centipede, using available genomic data. Comparative analyses revealed high sequence identity within functional domains and confirmed that the architecture for certain sex-determination genes is conserved in arthropods. This study provides a framework for identifying potential target genes that could be implicated in the process of sex determination in M. occidentalis and provides insight into the conservation and change of the molecular components of sex determination in arthropods.
Kamran, Muhammad; Mirza, Jawwad Hassan; Alatawi, Fahad Jaber
Abstract The two tetranychid genera Paraplonobia Wainstein and Neopetrobia Wainstein (Trombidiformes: Tetranychidae) are reported for the first time from Saudi Arabia. Three new species Paraplonobia (Anaplonobia) arabica Mirza & Alatawi, sp. n., Paraplonobia (Anaplonobia) haloxylonia Alatawi & Mirza, sp. n. and Paraplonobia (Anaplonobia) tabukensis Kamran & Alatawi, sp. n. are described and illustrated based on adult females, collected from Prosopis juliflora (SW.) Dc. (Fabaceae) and Haloxylon salicornicum Bunge (Amaranthaceae) from two different regions of Saudi Arabia. Neopetrobia mcgregori (Pritchard and Baker) is redescribed and illustrated based on female collected from Cynodon dactylon L. (Poaceae).The diagnostic morphological features including leg chaetotaxy of all known species of the subgenus Anaplonobia is tabulated. A key to the world species of the genus Paraplonobia is also provided. PMID:27408589
Urbaneja, Alberto; Pascual-Ruiz, Sara; Pina, Tatiana; Abad-Moyano, Raquel; Vanaclocha, Pilar; Montón, Helga; Dembilio, Oscar; Castañera, Pedro; Jacas, Josep A
Three groups of natural enemies are fundamental in citrus IPM in Spain: coccinellid and phytoseiid predators and hymenopteran parasitoids. Tetranychus urticae Koch is an important pest affecting citrus, for which biological control has not yet been achieved; therefore, acaricides are commonly used to control it. The goal of this study was to measure the efficacy of different acaricides on this mite and their side effects on three natural enemies relevant for citrus (Cryptolaemus montrouzieri Mulsant, Neoseiulus californicus McGregor and Aphidius colemani Viereck). Some products proved highly effective against T. urticae and harmless to A. colemani (mineral oil, tebufenpyrad, clofentezine and fenazaquin). However, almost all products tested were slightly harmful for both the predators considered. Fenazaquin was even moderately harmful for N. californicus. Further studies, like that presented here, are necessary to gain a better understanding of integrating biological and chemical controls. When considering both efficacy and side effects on beneficial arthropods, the best options would seem to be mineral oil, tebufenpyrad and clofentezine. However, it is urgent to complete testing of the side effects of the acaricides used in citrus. This question is crucial if the fact that two recently introduced Tetranychidae are being controlled in citrus by chemical means exclusively is considered.
Zou, Zhiwen; Min, Qiang; Xiao, Shungen; Xin, Tianrong; Xia, Bin
Effects of five photoperiods (Light:Dark = 4:20, 8:16; 12:12, 16:8, 20:4) on the development, survival and reproduction of Neoseiulus barkeri Hughes fed on storage mite Tyrophagus putrescentiae (Schrank) were examined under laboratory conditions at 85 % relative humidity and 24 °C. Development time of almost all immature stages in N. barkeri was the shortest (5.43 ± 0.12 days) under 12 h of daylight. Total duration of immature stages was as high as 8.55 ± 0.16 days during the longest photoperiod. Photoperiod had no effect on hatching rate, but did affect survival of larvae, protonymphs and deutonymphs. Total survivorship ranged from 20 (4:20) to 60 % (12:12). Under 12 h daylight, female adults had the shortest pre- and post-oviposition period, longest oviposition period and longevity, largest total number of eggs (15.95) and and highest daily egg production (1.43) per female. Under 12 h light, N. barkeri experienced its highest net reproductive rate (R 0 = 11.791), intrinsic rate of increase (r m = 0.180), and finite rate of increase (λ = 1.197), and lowest mean generation time (t = 13.71 days) and population doubling time (DT = 3.86 days). All demographic parameters displayed a parabolic relationship with photoperiod. The results of the present study indicated that the photoperiod of 12:12 is optimal for the development and reproduction of N. barkeri fed on T. putrescentiae, and that N. barkeri may serve most efficiently as a biological control agent under this regime.
Pekas, Apostolos; Palevsky, Eric; Sumner, Jason C; Perotti, M Alejandra; Nesvorna, Marta; Hubert, Jan
Neoseiulus cucumeris is a predatory mite used for biological control of arthropod pests. Mass-reared predators are fed with factitious prey mites such as Tyrophagus putrescentiae. Although some information on certain endosymbionts of N. cucumeris and T. putrescentiae exists, it is unclear whether both species share bacterial communities. The bacterial communities in populations of predator and prey mites, as well as the occurence of potential acaropathogenic bacteria were analyzed. The comparisons were based on the following groups: (i) N. cucumeris mass-production; (ii) N. cucumeris laboratory population with disease symptoms; (iii) T. putrescentiae pure populations and; (iv) T. putrescentiae from rearing units of N. cucumeris. Only 15% of OTUs were present in all samples from predatory and prey mite populations (core OTUs): the intracellular symbionts Wolbachia, Cardinium, plus other Blattabacterium-like, Solitalea-like, and Bartonella-like symbionts. Environmental bacteria were more abundant in predatory mites, while symbiotic bacteria prevailed in prey mites. Relative numbers of certain bacterial taxa were significantly different between the microbiota of prey mites reared with and without N. cucumeris. No significant differences were found in the bacterial communities of healthy N. cucumeris compared to N. cucumeris showing disease symptoms. We did not identify any confirmed acaropathogenic bacteria among microbiota.
Barbar, Ziad; Tixier, Marie-Stéphane; Cheval, Brigitte; Kreiter, Serge
The abundance and diversity of phytoseiid mites were surveyed from April to September 2003 to 2005 in vineyards (Grenache and Syrah cultivars) co-planted with rows of Sorbus domestica or Pinus pinea and in monoculture plots of grapes in the South of France. Densities of phytoseiid mites were different on the two tree species, with P. pinea a more suitable host than S. domestica. Typhlodromus (Typhlodromus) exhilaratus was the dominant species occurring on grapes and on co-planted rows of S. domestica and P. pinea, whereas T. (T.) phialatus was the most abundant species in monoculture plots of both S. domestica and P. pinea. Factors determining the dominance of T. (T.) phialatus over T. (T.) exhilaratus in monoculture trees are discussed. In this study, agroforestry management did not affect phytoseiid diversity in vineyards, but did affect phytoseiid density, especially in 2005. The results obtained in 2003 and 2004 are not easy to discuss in this regard because of the low densities of mites observed during these 2 years (very dry climatic conditions and pesticide applications).
Galendromus occidentalis (Nesbitt) is one of several phytoseiid species that are available for purchase to supplement endemic predator populations that are not providing sufficient control of spider mites. We performed a series of releases of commercially reared G. occidentalis in commercial apple (...
Gadino, Angela N; Walton, Vaughn M
The beneficial mite Typhlodromus pyri is a key predator of grapevine rust mite Calepitrimerus vitis in Pacific coastal vineyards. Rust mite feeding has been associated with damage such as stunted, deformed shoot growth and reductions in fruit yield. The life history traits of T. pyri were assessed at seven constant temperatures (12.5, 15, 17.5, 20, 25, 30 and 35 °C) to determine population parameters providing data to better predict biological control of C. vitis populations by T. pyri in vineyards. Successful development from the egg to adult stage was observed at temperatures ranging from 15 to 30 °C. Constant exposure to 12.5 and 35 °C resulted in 100 % mortality in immature T. pyri. Developmental times, fecundity and longevity were highest at 25 °C. The estimated minimum and maximum developmental thresholds were 7.24 and 42.56 °C, respectively. Intrinsic rate of increase (r ( m )) was positive from 15 to 30 °C indicating population growth within this range of temperatures. Net reproductive rate and intrinsic rate of increase were greatest at 25 °C. These developmental parameters can be used to estimate population growth, determine seasonal phenology and aid in conservation management of T. pyri. Results presented in this study will aid in evaluating the effectiveness of T. pyri as a key biological control agent of C. vitis during different periods of the growing season in Pacific Northwest vineyards.
Bostanian, Noubar J; Thistlewood, Howard M A; Hardman, John M; Racette, Gaétan
A laboratory evaluation of fenbuconazole, myclobutanil propiconazole, boscalid, fenhexamid and pyraclostrobin revealed these fungicides to be harmless to adult Galendromus occidentalis. None of these fungicides affected adversely fecundity and egg viability. Elemental sulphur also had no effect on adults and fecundity. However, 72.4% of the young larvae perished after hatching. The six novel fungicides are safer alternatives to sulphur in perennial crops in British Columbia.
Goleva, Irina; Zebitz, Claus P W
The predacious mite Amblyseius swirskii Athias-Henriot is used as a biological control agent against various pests in greenhouses. Pollen offered as supplementary food is reported to improve their fast establishment and performance. However, the nutritional suitability of different pollens for A. swirskii is not sufficiently known yet. Pollens of 21 plant species were offered to the mites as exclusive food during preimaginal development. Preimaginal mortality and developmental time have been assessed, followed by a life-table analysis of the emerged adults and a calculation of demographic parameters. Amblyseius swirskii can feed exclusively on pollen, but the nutritional value of the pollens differed significantly. Pollens of Lilium martagon and Hippeastrum sp. were toxic, causing 100 % preimaginal mortality, probably due to secondary plant compounds. Hibiscus syriacus pollen was absolutely incompatible for the juvenile and adult mites, possibly due to their external morphology, differing from all the other pollens tested and leading to 100 % preimaginal mortality also. Considering all parameters, feeding on Aesculus hippocastanum, Crocus vernus, Echinocereus sp. and Paulownia tomentosa pollens lead to the best performance of the mites. Feeding on most pollens resulted in no or low preimaginal mortality of A. swirskii, but affected significantly developmental time, adult longevity, and reproduction parameters. Commercial bee pollen was not able to improve life-table parameters compared to pure pollen of the plant species. Pollens of Helianthus annuus, Corylus avellana and a Poaceae mix were less suitable as food source and resulted in a poor performance of all tested parameters. Compared with literature data, 18 pollens tested proved to be a similar or better food source than cattail pollen, qualifying A. swirskii as a positively omnivorous type IV species. Pollens of Ricinus communis and Zea mays can be recommended as supplementary food offered as banker plants, and A. hippocastanum and Betula pendula pollen is recommended to be used as dispersible pollen in greenhouses.
Gnanvossou, Désiré; Hanna, Rachid; Dicke, Marcel
Typhlodromalus manihoti and Typhlodromalus aripo are exotic predators of the cassava green mite Mononychellus tanajoa in Africa. In an earlier paper, we showed that the two predators were attracted to odors from M. tanajoa-infested cassava leaves. In addition to the key prey species, M. tanajoa, two alternative prey mite species, Oligonychus gossypii and Tetranychus urticae also occur in the cassava agroecosystem. Here, we used a Y-tube olfactometer to determine the attraction of the predators to odors from O. gossypii- or T. urticae-infested cassava leaves and their prey-related odor preference. T. aripo but not T. manihoti was slightly attracted to odors from O. gossypii-infested leaves. Both predator species showed a stronger response to odors from cassava leaves infested by M. tanajoa over odors from cassava leaves infested by O. gossypii. Neither predator species was attracted to odors from T. urticae-infested leaves and the predators preferred the odors from M. tanajoa-infested leaves over those from T. urticae-infested leaves. When O. gossypii was present together with M. tanajoa on the same leaves or on different sets of leaves offered together as an odor source the two predators were attracted. In contrast, after mixing non-attractive odors from T. urticae-infested leaves with attractive odors from M. tanajoa-infested leaves, neither T. aripo nor T. manihoti was attracted. Ecological advantages and disadvantages of the predators' behavior and possible implications for biological control of M. tanajoa are discussed.
Massaro, Marcela; Martin, João Pedro Ignez; de Moraes, Gilberto José
Phytoseiid mites are commonly used as biological control agents of mite and small insect pests. To facilitate the production of phytoseiids, alternative food sources have been evaluated. The aim of this study was to evaluate the suitability of different food sources for the rearing of the phytoseiids Amblyseius tamatavensis Blommers, Euseius concordis (Chant) and Neoseiulus anonymus (Chant and Baker). This study evaluated the levels of oviposition of these predators when fed with 15 Astigmatina (Sarcoptiformes) mite species, one species of a bacteriophagous nematode, and pollen from five plant species. The highest oviposition rates of A. tamatavensis were obtained when fed on the mites Thyreophagus cracentiseta Barbosa, OConnor & Moraes and Aleuroglyphus ovatus (Troupeau) (2.6 and 2.1 eggs/female/day, respectively). The five highest oviposition levels of E. concordis occurred when the food source was pollen, especially of Ricinus communis L. (1.7 eggs/female/day). The evaluated oviposition levels of N. anonymus were at most 0.5 eggs/female/day on all food sources. The construction of life tables of A. tamatavensis and E. concordis with the two most favorable food sources showed that in both cases the values of rm were higher when the predator was fed with T. cracentiseta and R. communis, respectively. The possible use of pollen of Elaeis guineensis L. should be further evaluated, given the acceptance of this type of pollen by E. concordis and the ease of obtaining large amounts of this pollen in areas where this crop is grown.
Walzer, Andreas; Schausberger, Peter
The adaptive canalization hypothesis predicts that highly fitness-relevant traits are canalized via past selection, resulting in low phenotypic plasticity and high robustness to environmental stress. Accordingly, we hypothesized that the level of phenotypic plasticity of male body size of the predatory mites Phytoseiulus persimilis (low plasticity) and Neoseiulus californicus (high plasticity) reflects the effects of body size variation on fitness, especially male lifetime reproductive success (LRS). We first generated small and standard-sized males of P. persimilis and N. californicus by rearing them to adulthood under limited and ample prey supply, respectively. Then, adult small and standard-sized males were provided with surplus virgin females throughout life to assess their mating and reproductive traits. Small male body size did not affect male longevity or the number of fertilized females but reduced male LRS of P. persimilis but not N. californicus. Proximately, the lower LRS of small than standard-sized P. persimilis males correlated with shorter mating durations, probably decreasing the amount of transferred sperm. Ultimately, we suggest that male body size is more strongly canalized in P. persimilis than N. californicus because deviation from standard body size has larger detrimental fitness effects in P. persimilis than N. californicus. © 2014 The Authors. Biological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111, 889–899. PMID:25132689
The response of Typhlodromus pyri, a key predator of grapevine rust mite (Calepitrimerus vitis), to MeSA was tested using a Y-tube olfactometer in laboratory bioassays. Six doses ranging from 200 to 0.002 µg of diluted MeSA were tested. Significantly higher proportions of T. pyri preferred MeSA at ...
Duso, Carlo; Ahmad, Shakeel; Tirello, Paola; Pozzebon, Alberto; Klaric, Virna; Baldessari, Mario; Malagnini, Valeria; Angeli, Gino
Kampimodromus aberrans is an effective predatory mite in fruit orchards. The side-effects of insecticides on this species have been little studied. Field and laboratory experiments were conducted to evaluate the effects of insecticides on K. aberrans. Field experiments showed the detrimental effects of etofenprox, tau-fluvalinate and spinosad on predatory mites. Spider mite (Panonychus ulmi) populations reached higher densities on plots treated with etofenprox and tau-fluvalinate than in the other treatments. Single or multiple applications of neonicotinoids caused no detrimental effects on predatory mites. In the laboratory, spinosad and tau-fluvalinate caused 100 % mortality. Etofenprox caused a significant mortality and reduced fecundity. The remaining insecticides did not affect female survival except for imidacloprid. Thiamethoxam, clothianidin, thiacloprid, chlorpyrifos, lufenuron and methoxyfenozide were associated with a significant reduction in fecundity. No effect on fecundity was found for indoxacarb or acetamiprid. Escape rate of K. aberrans in laboratory was relatively high for etofenprox and spinosad, and to a lesser extent thiacloprid. The use of etofenprox, tau-fluvalinate and spinosad was detrimental for K. aberrans and the first two insecticides induced spider mite population increases. The remaining insecticides caused no negative effects on predatory mites in field trials. Some of them (reduced fecundity and repellence) should be considered with caution in integrated pest management programs.
Montserrat, M; de la Peña, F; Hormaza, J I; González-Fernández, J J
The persea mite Oligonychus perseae is a pest of avocado trees that builds extremely dense webbed nests that protect them against natural enemies, including phytoseiid mites. Nests have one or two marginal entrances that are small and flattened. The predatory mite Neoseiulus californicus co-occurs with O. perseae in the avocado orchards of the south-east of Spain. Penetration inside nests through the entrances by this predator is thought to be hindered by its size and its globular-shaped body. However, in the field it has repeatedly been found inside nests that were clearly ripped. Perhaps penetration of the nests has been facilitated by nest wall ripping caused by some other species or by unfavourable abiotic factors. However, to assess whether N. californicus is also able to enter the nest of O. perseae by itself, we carried out laboratory experiments and made a short film. They show how this predator manages to overcome the webbed wall, and that it can penetrate and forage inside nests of O. perseae.
van den Boom, C E M; van Beek, T A; Dicke, M
Plants infested with the spider mite Tetranychus urticae Koch, may indirectly defend themselves by releasing volatiles that attract the predatory mite Phytoseiulus persimilis Athias-Henriot. Several plants from different plant families that varied in the level of spider mite acceptance were tested in an olfactometer. The predatory mites were significantly attracted to the spider mite-infested leaves of all test plant species. No differences in attractiveness of the infested plant leaves were found for predatory mites reared on spider mites on the different test plants or on lima bean. Thus, experience with the spider mite-induced plant volatiles did not affect the predatory mites. Jasmonic acid was applied to ginkgo leaves to induce a mimic of a spider mite-induced volatile blend, because the spider mites did not survive when incubated on ginkgo. The volatile blend induced in ginkgo by jasmonic acid was slightly attractive to predatory mites. Plants with a high degree of direct defence were thought to invest less in indirect defence than plants with a low degree of direct defence. However, plants that had a strong direct defence such as ginkgo and sweet pepper, did emit induced volatiles that attracted the predatory mite. This indicates that a combination of direct and indirect defence is to some extent compatible in plant species.
Baker, Anne S
Mites and ticks (Acari) have been found in a variety of archaeological situations. Their identification has enabled data on habitat and dietary preferences to be obtained, and these have been used to interpret study sites. Despite this, Acari are not routinely considered in analyses in the way that other environmental components are. Like forensic science, archaeology draws on biological material to rebuild past human activity, and acarology has the potential to provide a much greater amount of evidence to both than is currently the case. As an aid to workers in these fields, an overview is presented of the Acari that have been extracted from archaeological samples, the situations in which they were found and the contribution their presence can make to the interpretation of sites.
Herron, G A; Rophail, J; Wilson, L J
The responses of Tetranychus urticae Koch from Australian cotton to chlorfenapyr has been monitored since the 1997--1998 growing season. Resistance was first detected in the 2001--2002 season and then increased quickly in both level and proportion of resistant strains detected. In response, the resistance management strategy for chlorfenapyr use in cotton was altered and now recommends a further restriction of use from two to one spray per season. There was no evidence of negative cross-resistance to the pyrethroid bifenthrin, but chlorfenapyr was associated with an undefined negative cross-resistance.
Tollerup, Kris E; Marcum, Daniel; Wilson, Rob; Godfrey, Larry
The two-spotted spider mite, Tetranychus urticae Koch, is an economic pest on peppermint [Mentha x piperita (L.), 'Black Mitcham'] grown in California. A sampling plan for T. urticae was developed under Pacific Northwest conditions in the early 1980s and has been used by California growers since approximately 1998. This sampling plan, however, is cumbersome and a poor predictor of T. urticae densities in California. Between June and August, the numbers of immature and adult T. urticae were counted on leaves at three commercial peppermint fields (sites) in 2010 and a single field in 2011. In each of seven locations per site, 45 leaves were sampled, that is, 9 leaves per five stems. Leaf samples were stratified by collecting three leaves from the top, middle, and bottom strata per stem. The on-plant distribution of T. urticae did not significantly differ among the stem strata through the growing season. Binomial and enumerative sampling plans were developed using generic Taylor's power law coefficient values. The best fit of our data for binomial sampling occurred using a tally threshold of T = 0. The optimum number of leaves required for T urticae at the critical density of five mites per leaf was 20 for the binomial and 23 for the enumerative sampling plans, respectively. Sampling models were validated using Resampling for Validation of Sampling Plan Software.
Arimoto, Makoto; Satoh, Masaru; Uesugi, Ryuji; Osakabe, Masahiro
A polymerase chain reaction (PCR)-restriction fragment length polymorphism (PCR-restriction fragment-length polymorphism)-based method for species identification was applied to 14 Tetranychus spider mite species, which were dominant species intercepted at Japanese import plant quarantine. We sequenced the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA (rDNA), which included the partial ends of the 18S and 28S ribosomal RNA genes, 5.8S ribosomal RNA gene, and two internal transcribed spacers (ITS1 and ITS2) for 15 populations of the 14 species. We analyzed the recognition sites of four restriction endonucleases, which had been proposed for discrimination of Japanese Tetranychus species, and constructed a scheme for Tetranychus species identification by PCR-restriction fragment-length polymorphism. We then applied the scheme to 245 individuals from 199 populations, most of them were from foreign countries. As a result, all 14 species were correctly identified using PCR-restriction fragment-length polymorphism. This demonstrates the usefulness of the PCR-restriction fragment-length polymorphism method for the worldwide identification of Tetranychus species.
Yang, Si-Xia; Guo, Chao; Zhao, Xiu-Ting; Sun, Jing-Tao; Hong, Xiao-Yue
The two-spotted spider mite, Tetranychus urticae Koch has two forms: green form and red form. Understanding the molecular basis of how these two forms established without divergent genetic background is an intriguing area. As a well-known epigenetic process, DNA methylation has particularly important roles in gene regulation and developmental variation across diverse organisms that do not alter genetic background. Here, to investigate whether DNA methylation could be associated with different phenotypic consequences in the two forms of T. urticae, we surveyed the genome-wide cytosine methylation status and expression level of DNA methyltransferase 3 (Tudnmt3) throughout their entire life cycle. Methylation-sensitive amplification polymorphism (MSAP) analyses of 585 loci revealed variable methylation patterns in the different developmental stages. In particular, principal coordinates analysis (PCoA) indicates a significant epigenetic differentiation between female adults of the two forms. The gene expression of Tudnmt3 was detected in all examined developmental stages, which was significantly different in the adult stage of the two forms. Together, our results reveal the epigenetic distance between the two forms of T. urticae, suggesting that DNA methylation might be implicated in different developmental demands, and contribute to different phenotypes in the adult stage of these two forms. © 2017 Institute of Zoology, Chinese Academy of Sciences.
Osakabe, Masahiro; Kotsubo, Yu; Tajima, Ryusen; Hinomoto, Norihide
Species identification is a basic issue in biosecurity. Polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) is a useful molecular diagnostic tool for species identification. However, the lack of transferability of data has been a serious shortcoming of this method. A RFLP catalog, i.e., a graph of PCR-RFLP patterns expected from sequence data, was devised as a tool to facilitate PCR-RFLP data sharing among laboratories. Twelve species of Tetranychus spider mites have been recorded in Japan to date. In this study, we analyzed DNA sequences of the internal transcribed spacer (ITS) region in nuclear ribosomal DNA of 11 Tetranychus species. For the species identification using PCR-RFLP, we chose six candidates from 131 restriction endonucleases and developed an RFLP catalog of all known Japanese Tetranychus species except Tetranychus neocaledonicus André. The RFLP catalog revealed that most Tetranychus species had diagnostic restriction fragments. The RFLP catalog is transferable and simple molecular diagnostic tool, and it has the ability to add more species and newly found intraspecific variations. Therefore, we believe that the RFLP catalog will contribute to biosecurity as a practical diagnostic tool for species identification of spider mites.
Soto, Alberto; Venzon, Madelaine; Oliveira, Rafael M; Oliveira, Hamilton G; Pallini, Angelo
Tetranychus evansi Baker & Pritchard is an important pest of solanaceous plants, including tomatoes. This mite is characterized by a high reproductive rate, which leads to high population growth in a short period of time causing important economic damage. Control of T. evansi is mainly through synthetic acaricides. In searching for environmentally friendly control measures, we evaluated the efficiency of alternative products to control T. evansi on tomato plants under greenhouse conditions. The products tested were lime sulphur and neem based products. We first estimated the lethal concentration (LC) and instantaneous rate of increase (r i) of T. evansi exposed to different product concentrations in laboratory conditions, and later tested the efficacy of LC95 and the concentrations that restrained mite population growth (r i = 0) in greenhouse conditions. The following treatments were repeated three times: NeemPro (81.0 and 71.6 mg a.i./l), Natuneem (31.1 and 20.4 mg ai/l), Organic Neem (39.1 and 30.4 mg a.i./l), lime sulphur (1.0 and 0.6%) and water (control). For all products, control provided by LC95 was higher than provided for lower concentrations (r i = 0) one day after spraying. However, after five days, for both concentrations, the percentage of T. evansi population reduction was superior to 95% and increased over time. Only plants sprayed with Natuneem (31.1 mg a.i./l) showed symptoms of phytotoxicity. Lime sulphur and neem based products, applied in appropriate concentrations and formulations, bear out as a viable alternative to control T. evansi on tomato plants.
Kim, Young-Joon; Lee, Si-Hyeock; Lee, Si-Woo; Ahn, Young-Joon
A field colony of the Two-spotted spider mite, Tetranychus urticae (Koch), resistant to fenpyroximate was further selected with fenpyroximate 5SC for 20 generations at a selection pressure of 30-50% mortality (designated as FR-20 strain). Resistance and cross-resistance levels of the FR-20 strain to 18 acaricides were determined using a spray method. The FR-20 strain was extremely resistant to fenpyroximate [resistance ratio (RR) 252]. The strain exhibited extremely strong positive cross-resistance to acrinathrin (RR 196), and high levels of resistance to benzoximate (RR 55) and propargite (RR 64). Moderate levels of cross-resistance (RR 11-40) to abamectin, fenbutatin oxide, fenpropathrin, pyridaben, pyridaben + bifenthrin and tebufenpyrad were observed. The FR-20 strain showed low levels of resistance (RR < 10) to azocyclotin, bromopropylate, chlorfenapyr, chlorfenapyr + bifenthrin, chlorfenapyr + pyridaben, dicofol, fenazaquin and milbemectin. Synergist experiments with different metabolic inhibitors revealed that piperonyl butoxide had the greatest effect on the efficacy of fenpyroximate, followed by iprobenfos and triphenyl phosphate. In a comparative assay with detoxifying enzymes, the FR-20 strain showed 2.5-fold higher activity in p-nitroanisole-O-demethylation, and 2.5- and 2.2-fold higher activities in alpha- and beta-naphthyl acetate hydrolysis, respectively. These results suggested that enhanced activities of both mixed-function oxidases and esterases likely contribute to the fenpyroximate resistance of the FR-20 strain of T urticae.
Zhang, Yong-Qiang; Yang, Zhen-Guo; Ding, Wei; Luo, Jin-Xiang
The study aimed to investigate the synergistic activity of scopoletin and bisdemethoxycurcumin (BDMC) against the carmine spider mite Tetranychus cinnabarinus. The acaricidal activities of mixtures of scopoletin and BDMC against T. cinnabarinus female adults were measured via slide dipping and leaf disc dipping. A mathematical model was established by SPSS software. Bioassays for multiple effects including contact, ovicidal, cowpea root intake, repellency and oviposition inhibitory activity were carried out. The optimal mass ratio of the mixture of scopoletin and BDMC (at their respective LC(50)), the median lethal concentration (LC(50)) and the co-toxicity coefficient were 7:6, 0.19 mg/mL and 129, respectively. LC(50) values of contact activities of the mixture at optimal ratio against adults, nymphs, larvae, and eggs were 0.19, 0.18, 0.06, and 1.52 mg/mL, respectively. LC(50) values of cowpea root intake activity against adults and nymphs were 5.62 and 6.52 mg/mL, respectively. The highest repellent rates against adults and nymphs were 69.5% and 72.5%, respectively. The mixture of scopoletin and BDMC at the optimal mass ratio possessed strong acaricidal activity against T. cinnabarinus at various developmental stages.
Yang, Zhen-Guo; Zhang, Yong-Qiang; Ding, Wei; Luo, Jin-Xiang
By using slide-dip bioassay method under laboratory condition, an investigation was made on the lethal effects of scopoletin, bisdemethoxycurcumin (BDMC), and their combination at an optimal mass ratio (7:6) of scopoletin to BDMC against the adult females of Tetranychus cinnabarinus Boisd. A time-dose mortality model (TDM) was established, which passed the Hosmer-Lemeshow test. The sensitivity of the adult females to the concentration change of the acaricides was in the sequence of scopoletin > optimal mass ratio of scopoletin to BDMC > BDMC. The peak mortality of the female adults was found at 32, 28 and 32 h after treated with BDMC, scopoletin, and their combination at the optimal mass ratio, respectively. The values of the LC50 and LC90 at 48 h after treated with BDMC, scopoletin, and their combination at the optimal mass ratio were 0.3324, 0.2035 and 0.2195 mg x mL(-1), and 2.1198, 0.9521 and 1.1617 mg x mL(-1), and the median lethal time (LT50) of BDMC, scopoletin, and their combination at the optimal mass ratio was 7.4, 6.0 and 6.1 h at the concentration 1.0 mg x mL(-1), and 6.4, 4.8 and 5.0 h at the concentration 2.0 mg x mL(-1), respectively. The acaricidal activity and time-dose response of the optimal combination of scopoletin and BDMC were closer to those of scopoletin, suggesting a synergistic acaricidal activity of the combination of scopoletin and BDMC, which was worthy to be developed for application.
Vásquez-Ordóñez, Aymer Andrés; Parsa, Soroush
The genus Mononychellus is represented by 28 herbivorous mites. Some of them are notorious pests of cassava (Manihot esculenta Crantz), a primary food crop in the tropics. With the exception of Mononychellus tanajoa (Bondar), their geographic distribution is not widely known. This article therefore reports observational and specimen-based occurrence data of Mononychellus species associated with cassava. The dataset consists of 1,513 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT's Arthropod Reference Collection (CIATARC). Most of the records are from the genus' native range in South America and were documented between 1980 and 2000. Approximately 61% of the records belong to M. tanajoa, 25% to M. caribbeanae (McGregor), 10% to M. mcgregori (Flechtmann and Baker) and 2% to M. planki (McGregor). The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF).
Vásquez-Ordóñez, Aymer Andrés; Parsa, Soroush
Abstract The genus Mononychellus is represented by 28 herbivorous mites. Some of them are notorious pests of cassava (Manihot esculenta Crantz), a primary food crop in the tropics. With the exception of Mononychellus tanajoa (Bondar), their geographic distribution is not widely known. This article therefore reports observational and specimen-based occurrence data of Mononychellus species associated with cassava. The dataset consists of 1,513 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT’s Arthropod Reference Collection (CIATARC). Most of the records are from the genus’ native range in South America and were documented between 1980 and 2000. Approximately 61% of the records belong to M. tanajoa, 25% to M. caribbeanae (McGregor), 10% to M. mcgregori (Flechtmann and Baker) and 2% to M. planki (McGregor). The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF). PMID:24899828
Zhang, Ke; Luo, Lingyan; Chen, Xieting; Hu, Meiying; Hu, Qiongbo; Gong, Liang; Weng, Qunfang
The effective dose of irradiation to control pest mites in quarantine has been studied extensively, but the molecular mechanisms underlying the effects of the irradiation on mites are largely unknown. In this study, exposure to 400 Gy of γ rays had significant (p < 0.05) effects on the adult survival, fecundity and egg viability of Panonychus citri. The irradiation caused the degradation of the DNA of P. citri adults and damaged the plasma membrane system of the egg, which led to condensed nucleoli and gathered yolk. Additionally, the transcriptomes and gene expression profiles between irradiated and non-irradiated mites were compared, and three digital gene expression libraries were assembled and analyzed. The differentially expressed genes were putatively involved in apoptosis, cell death and the cell cycle. Finally, the expression profiles of some related genes were studied using quantitative real-time PCR. Our study provides valuable information on the changes in the transcriptome of irradiated P. citri, which will facilitate a better understanding of the molecular mechanisms that cause the sterility induced by irradiation. PMID:26569230
Migeon, Alain; Ferragut, Francisco; Escudero-Colomar, Lucía Adriana; Fiaboe, Komi; Knapp, Markus; de Moraes, Gilberto J; Ueckermann, Eddie; Navajas, Maria
Predicting the potential geographical distribution of a species is particularly important for pests with strong invasive abilities. Tetranychus evansi Baker & Pritchard, possibly native to South America, is a spider mite pest of solanaceous crops. This mite is considered an invasive species in Africa and Europe. A CLIMEX model was developed to predict its global distribution. The model results fitted the known records of T. evansi except for some records in dry locations. Dryness as well as excess moisture stresses play important roles in limiting the spread of the mite in the tropics. In North America and Eurasia its potential distribution appears to be essentially limited by cold stress. Detailed potential distribution maps are provided for T. evansi in the Mediterranean Basin and in Japan. These two regions correspond to climatic borders for the species. Mite establishment in these areas can be explained by their relatively mild winters. The Mediterranean region is also the main area where tomato is grown in open fields in Europe and where the pest represents a threat. According to the model, the whole Mediterranean region has the potential to be extensively colonized by the mite. Wide expansion of the mite to new areas in Africa is also predicted. Agricultural issues highlighted by the modelled distribution of the pest are discussed.
Bustos, A; Rodríguez, D; Cure, J R; Cantor, F
The supply of predatory mites as natural enemies is a key component to guarantee the success of biological pest control programs as alternatives to chemical control in commercial crops. To meet the demand for a supply of biologicals, the mass rearing of natural enemies is an option, and the first step must be to develop a standardized system that maximizes the production of prey. One choice for this first step is to use simulation models that can evaluate scenarios that are difficult or complex to address experimentally. In this work, a model was developed to evaluate the current management conditions for the mass rearing of the pest mite Tetranychus urticae Koch. Our aim was to identify alternative scenarios to maximize mite production through mass rearing that could be evaluated in real systems. We assumed that populations of T. urticae were regulated by the conditions of supply-demand theory and modeled the age structure, temperature effects, and individual phenology of T. urticae. The supply-demand theory of resources was used to regulate populations, which involved structured ages and temperature effects for the different stages in the development of individuals. We used the functional response and the paradigm of metabolic pool models to describe resource acquisition and allocation. We demonstrated that 7- to 14-day-old plants infested with 45 or 62 T. urticae/plant could reach 25,000 individuals/plant, being 50% of these preys at the preferred stages by the predator Phytoseiulus persimilis Athias-Henriot. Our theoretical model requires validation in experimental/real systems of mass rearing to better verify the validity of all of the parameters and predictions before commercial implementation.
Paulo, P D; Lima, C G; Dominiquini, A B; Fadini, M A M; Mendes, S M; Marinho, C G S
Plants can be attacked by a wide variety of herbivores. Thus, developing protective mechanisms for resistance against these agents is an advantage for survival and reproduction. Over the course of evolution, many resistance mechanisms against herbivory have been developed by the plants. Induced direct and indirect resistance mechanisms can manifest in plants after herbivore attack. The two-spotted spider mite Tetranychus urticae is not a pest of maize crops (Zea mays), despite being reported infesting plants that may have resistances against this herbivore. We tested the hypothesis that maize plants would be able to induce direct resistance against T. urticae after, evaluating the effect of T. urticae infestation in maize plants on the development and reproduction of conspecifics. We tested induced direct resistance performing infestation and measuring biological parameters upon a second infestation. Maize plants, 40 days after sowing, were divided into two groups: 30 not infested by T. urticae (clean plants clean) and, 30 infested by the spider mite. Infestation of maize plants by T. urticae reduced the conspecific female adult survival. However, no change in the survival of immature or reproduction was observed. These results suggest the induction of induced direct resistances in maize by T. urticae. This is first report of direct resistance induction in Z. mays by the two-spotted spider mite T. urticae.
Iwassaki, Larissa Akemi; Sato, Mário Eidi; Calegario, Fagoni Fayer; Poletti, Marcelo; Maia, Aline de Holanda Nunes
The twospotted spider mite (TSSM), Tetranychus urticae Koch, is one of the main pests on strawberry crops in Brazil. TSSM can be difficult to control due to acaricide resistance. The objective of this work was to compare the effect of conventional and integrated strawberry production (ISP) systems on mite abundance and acaricide resistance. The control of TSSM in ISP was based on the release of Neoseiulus californicus (McGregor) or application of a selective acaricide (propargite), when TSSM monitoring indicated the timing for the release of predaceous mites (1-3 mites per leaflet on 30% leaflets) or chemical intervention (>10 mites per leaflet). Only acaricides (abamectin, fenpyroximate) were applied in the conventional system. Integrated control of TSSM were sufficient to maintain a significantly lower pest infestation level, resulting in a sixfold reduction in the frequency of acaricide applications, and consequently, a lower selection pressure for acaricide resistance. Strategies for the management of TSSM in strawberry fields are described and discussed.
Sabater-Muñoz, B; Pascual-Ruiz, S; Gómez-Martínez, M A; Jacas, J A; Hurtado, M A
Tetranychus urticae Koch is a cosmopolitan phytophagous mite considered as the most polyphagous species among spider mites. Population genetic studies using molecular markers such as microsatellites have proven to be extremely informative to address questions about population structure, phylogeography and host preferences. The aim of this study was to increase the available molecular tools to gain insight into the genetic structure of T. urticae populations of citrus orchards, which might help in their management. Five microsatellite DNA libraries were developed using probes with the motifs CT, CTT, GT and CAC following the FIASCO protocol. Positive clones, those that included the insert with the microsatellite, were detected using the PIMA-PCR technique. Combinations of primers were designed on 22 out of 32 new microsatellites loci and their polymorphism was tested in four populations sampled along the eastern coast of Spain. Eleven successful amplifications were obtained. Cross amplification was tested in the tetranychids Aphlonobia histricina, Eutetranychus banksi, E. orientalis, Oligonychus perseae, Panonychus citri, Tetranychus evansi, T. okinawanus and T. turkestani, and the phytoseiids Amblyseius swirskii, A. cucumeris, A. andersoni, Euseius stipulatus, Neoseiulus barkeri, N. californicus, Phytoseiulus persimilis and Typhlodromus phialatus. Eight successful cross amplifications were obtained.
The impact of linamarin and lotaustralin content in the leaves of Phaseolus lunatus L. on the second and third trophic levels was studied in Tetranychus urticae (Koch) and its predator Phytoseiulus persimilis Athias-Henriot. Chemical analyzes showed that the content of linamarin was higher in termin...
Zhang, Guo-Hao; Liu, Huai; Wang, Jin-Jun; Wang, Zi-Ying
Changes in temperature are known to cause a variety of physiological stress responses in insects and mites. Thermal stress responses are usually associated with the increased generation of reactive oxygen species (ROS), resulting in oxidative damage. In this study, we examined the time-related effect (durations for 1, 2, 3, and 5 h) of thermal stress conditions-i.e., relatively low (0, 5, 10, and 15 °C) or high (35, 38, 41, and 44 °C) temperatures-on the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), peroxidase (POX), glutathione S-transferases (GSTs), and total antioxidant capacity (T-AOC) of the predatory mite Neoseiulus cucumeris. Also the lipid peroxidation (LPO) levels of the predatory mite were measured under thermal stress conditions. The results confirmed that thermal stress results in a condition of so-called oxidative stress and the four antioxidant enzymes play an important role in combating the accumulation of ROS in N. cucumeris. CAT and POX activity changed significantly when the mites were exposed to cold and heat shock, respectively. The elevated levels of SOD and GSTs activity, expressed in a time-dependent manner, may have an important role in the process of antioxidant response to thermal stress. However, the levels of LPO in N. cucumeris were high, serving as an important signal that these antioxidant enzyme-based defense mechanisms were not always adequate to counteract the surplus ROS. Thus, we hypothesize that thermal stress, especially extreme temperatures, may contribute much to the generation of ROS in N. cucumeris, and eventually to its death.
Farazmand, Azadeh; Fathipour, Yaghoub; Kamali, Karim
This study was carried out on the ability of predatory thrips Scolothrips longicornis Priesner to feed on 2 phytoseiid species and vice versa. Also the effect of predation of Neoseiulus californicus (McGregor) on Typhlodromus bagdasarjani Wainstein and Arutunjan and vice versa was evaluated. The larvae, prepupae, and pupae of thrips and the eggs, larvae, and protonymphs of phytoseiids were selected as intraguild prey. The intraguild predation (IGP) among S. longicornis and 2 phytoseiid species was unidirectional and in favor of phytoseiids, i.e., S. longicornis was not able to feed on larval stages of 2 phytoseiids. However, N. californicus and T. bagdasarjani fed on the 1st instar larvae (1.39 and 0.80 per day), 2nd instar larvae (0.87 and 0.55 per day), prepupae (0.51 and 0.48 per day), and pupae of thrips (0.51 and 0.49 per day, respectively). Both phytoseiids fed on eggs, larvae, and protonymphal stages of each other. Females of N. californicus consumed more phytoseiid larvae (2.49 per day) than T. bagdasarjani, which consumed 1.08 N. californicus larvae per day. When Tetranychus urticae was presented as an extraguild prey, intensity of IGP between 2 species of phytoseiids and on larval stages of S. longicornis reduced significantly. Therefore, it is concluded that (i) IGP existed among the 3 examined species and lack of feeding of S. longicornis on 2 phytoseiid species can be justified by its feeding type (monophagy), (ii) N. californicus was much more prone to IGP than was T. bagdasarjani. © 2013 Institute of Zoology, Chinese Academy of Sciences.
Ghazy, Noureldin Abuelfadl; Suzuki, Takeshi; Amano, Hiroshi; Ohyama, Katsumi
To determine the optimum air temperature and water vapor pressure deficit (VPD) for the storage of the predatory mite, Neoseiulus californicus, 3-day-old mated females were stored at air temperatures of 0, 5, 10, or 15 °C and VPDs of 0.1, 0.3, or 0.5 kPa for 10, 20, or 30 days. At 10 °C and 0.1 kPa, 83 % of females survived after 30 days of storage; this percentage was the highest among all conditions. VPDs of 0.3 and 0.5 kPa regardless of air temperature, and an air temperature of 0 °C regardless of VPD were detrimental to the survival of the females during storage. Since the highest survival was observed at 10 °C and 0.1 kPa, the effect of the storage duration on the post-storage quality of the stored females and their progeny was investigated at 25 °C to evaluate the effectiveness of the storage condition. The oviposition ability of the stored females, hatchability, and sex ratio of their progeny were not affected even when the storage duration was extended to 30 days. Although a slight decrease in the survival during the immature stages of progeny was observed when the storage duration was ≥20 days, the population growth of N. californicus may not be affected when individuals stored in these conditions are applied to greenhouses and agricultural fields. The results indicate that mated N. californicus females can be stored at 10 °C and 0.1 kPa VPD for at least 30 days.
Sugawara, Reo; Ullah, Mohammad Shaef; Ho, Chyi-Chen; Gökçe, Ayhan; Chi, Hsin; Gotoh, Tetsuo
Temperature has significant effects on the development, survival, and reproduction of ectothermic organisms. In this study, we examined the effect of temperature on the demographic characteristics of two predatory mite species, Neosciulus womersleyi (Schicha) and N. longispinosus (Evans), reared on Tetranychus urticae Koch. The developmental and reproductive traits of both species were examined at 10 constant temperatures between 15 °C and 37.5 °C. The preadult development time of N. womersleyi and N. longispinosus decreased with increasing temperature until 32.5 °C and 35 °C, respectively. The lower developmental threshold (T0) and thermal constant (K) estimated by using a linear model were 11.61 °C and 69.36 DD for N. womersleyi and 11.92 °C and 61.5 DD for N. longispinosus, respectively. Total preoviposition period and total longevity of females and males of N. womersleyi and N. longispinosus decreased with increasing temperature. The mean generation time (T) first decreased with temperature until 32.5 and 35 °C for N. womersleyi and N. longispinosus, respectively, and then increased at higher temperatures. The R0 and r values first increased with temperature until 32.5 and 30 °C for N. womersleyi and N. longispinosus, respectively, and then decreased at higher temperatures. The R0 and r values for N. longispinosus at 37.5 °C were 0.3 offspring and -0.143 d-1, respectively. These results show that N. longispinosus is less fit than N. womersleyi at 37.5 °C. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Ahmad, Shakeel; Pozzebon, Alberto; Duso, Carlo
The predatory mites Kampimodromus aberrans (Oudemans), Amblyseius andersoni (Chant), Typhlodromus pyri Scheuten and Phytoseius finitimus Ribaga are important biological control agents in orchards and vineyards in Europe and elsewhere. They can coexist in the same habitat and engage in intraguild predation (IGP). In the laboratory we evaluated the longevity, fecundity and prey consumption of females of these predatory mites fed with heterospecific larvae considered as intraguild prey (IG-prey). The survival and age-specific oviposition curves of predatory mites fed with pollen were compared with those obtained on different IG-prey. We assessed the prey conversion rate into eggs expressed by the different IG-predator as an indicator of their capacity to persist when prey is diminishing. Results suggest that A. andersoni should be considered the superior intraguild predator but the least efficient in food conversion. Phytoseius finitimus appeared to suffer from intraguild predation, and its efficiency in food conversion was not superior to that of K. aberrans and T. pyri. The profiles of K. aberrans and T. pyri were less definite. The comparison between pollen and IG-prey diets confirmed the positive effect of pollen on the fecundity of all four predatory mite species. Fecundity was higher on pollen than on IG-prey. We can suggest that A. andersoni have the potential to exclude the other predatory mites only at high food resource availability, whereas low levels of food availability can favor the other species in IGP.
Kumar, Vivek; Xiao, Yingfang; McKenzie, Cindy L; Osborne, Lance S
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.
Teodoro, Adenir V; Pallini, Angelo; Oliveira, Claudinei
We used a Y-tube olfactometer to assess the sub-lethal effects of the acaricide fenbutatin oxide on the olfactory response of the predatory mite Iphiseiodes zuluagai towards odours from: (1) air or undamaged coffee plants; (2) undamaged or red spider mite Oligonychus ilicis-infested coffee plants; (3) undamaged or false spider mite Brevipalpus phoenicis-infested coffee plants. Predatory mite adult females were exposed to residues of fenbutatin oxide or distilled water on leaf discs during a period of 72 h prior experiments. When exposed to distilled water (control treatments), predatory mites significantly preferred undamaged plants over air, O. ilicis-infested plants over undamaged plants, and they did not prefer B. phoenicis-infested plants over undamaged plants. However, predatory mites that had been exposed to residues of fenbutatin oxide were neither attracted towards undamaged plants nor to O. ilicis-infested plants. Thus, fenbutatin oxide affected negatively the olfactory response of I. zuluagai. We conclude that sub-lethal-effect studies should be considered in pesticide selectivity programs since the ability of predatory mites to locate their prey may be negatively affected by non-lethal concentrations of pesticides.
Gugole Ottaviano, María F; Cédola, Claudia V; Sánchez, Norma E; Greco, Nancy M
Wild vegetation surrounding crops may provide temporary habitat and potential food sources for phytoseiids in different seasons. Monthly vegetation samples of wild plants adjacent to strawberry plants and wild plants in a vegetation strip close to the crop were taken. The frequency of Neoseiulus californicus, Tetranychus urticae and other mites and insects was recorded. In addition, in a laboratory assay, the survival, developmental time and fecundity of females fed on pollen of strawberry and pollen of wild plants where N. californicus was recorded during their flowering, were estimated. Pollen from Urtica urens, Lamium amplexicaule, Convolvulus arvensis, Sonchus oleraceous, Galega officinalis, and Fragaria x ananassa (strawberry) allowed development of N. californicus to adult, but not reproduction. Survival was 70-80 % when fed on pollen from S. oleraceus, G. officinalis and C. arvensis, 80-90 % when fed on pollen from U. urens and F. x ananassa, and more than 90 % when fed on T. urticae and on pollen from L. amplexicaule. In autumn and winter, U. urens, L. amplexicaule and S. oleraceous could promote the persistence of N. californicus when prey density in strawberry is low, offering T. urticae, thrips and pollen. In summer, pollen of C. arvensis and G. officinalis would contribute to the persistence of N. californicus when the strawberry crop is ending and offers scarce food resources. Although the pollen of these plants would not enable the predator population to increase, the presence of these plants in the vicinity of strawberry could contribute to the persistence of N. californicus population and help to limit T. urticae growth when this pest begins to colonize the crop.
Ullah, Mohammad Shaef; Hanawa, Masumi; Gotoh, Tetsuo
Neoseiulus womersleyi and N. californicus are two predators that are frequently used to control spider mites in fruit-tree orchards. Neoseiulus womersleyi used to be the dominant predator species in Japan, but since the 1990s in central and southwestern Japan, N. californicus populations have been increasing and have displaced populations of N. womersleyi. We previously observed the same phenomenon under laboratory conditions when these species were released at a 1:1 ratio, and attributed the displacement to asymmetrical intraguild predation. However, the ratio in fruit-tree orchards could be different from 1:1. Therefore, we hypothesized that differential susceptibilities to pesticides might accelerate species displacement of N. womersleyi by N. californicus, even if the ratio between these two species was extremely skewed in favor of N. womersleyi and no species displacement occurred otherwise. We examined the effects of 21 pesticides on egg-to-adult and adult survivorship in N. womersleyi and N. californicus. Among these pesticides, two neonicotinoids (acetamiprid and imidacloprid) had much severer effects on N. womersleyi than on N. californicus and thus could possibly account for the species displacement. When the two species were released onto leaf arenas at an N. californicus: N. womersleyi ratio of 1:9 in the absence of insecticide, no displacement was observed. However, just after acetamiprid or imidacloprid application, the proportion of N. californicus increased, causing N. californicus to displace N. womersleyi. Our results indicate that displacement in predator complexes of fruit-tree orchards could be due to different degrees of pesticide susceptibility.
Methyl salicylate (MeSA), an herbivore induced plant volatile, can potentially elicit control of pests through attraction of beneficial arthropods. This study evaluates the effect of synthetic MeSA lures (PredaLure) on arthropod populations during the 2009 and 2010 seasons in two Oregon vineyards (...
Riahi, Elham; Fathipour, Yaghoub; Talebi, Ali Asghar; Mehrabadi, Mohammad
Commercial production of Amblyseius swirskii Athias-Henriot based on storage mites needs both space and labor to maintain large cultures of these prey, and also may lead to health problems for workers. Therefore, the accessibility of a suitable artificial diet could eliminate the mentioned problems; however, the artificial diets must support the persistent production of high quality progeny. This study endeavored to find a more easily available and cheaper nutrient that may further reduce the cost of diet production for A. swirskii. The predator's performance was determined when it was fed on a basic artificial diet (AD1) composed of honey, sucrose, tryptone, yeast extract, and hen egg yolk, and on eight other artificial diets consisting of 80% AD1 enriched with different nutrients including maize pollen (AD2), hemolymph of Plusia gamma L. (AD3), Ephestia eggs (AD4), Artemis cysts (AD5), Ephestia last-instar larvae (AD6), multivitamin syrup (AD7), bovine serum albumin (AD8), and bull sperm (AD9). The lowest development time was on AD2. The highest value of fecundity and oviposition period were observed on AD5, followed by AD2 and AD4. The intrinsic rate of increase (r) and the finite rate of increase (λ) reached the maximal value on AD5. Feeding on AD2 and AD5 resulted in highest value of R0 (net reproductive rate). Our results indicated that Artemia cysts and maize pollen had better potential to be used as nutrient in artificial diet for mass production of A. swirskii. Overall, it seems that AD2 is the most cost effective than others. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Abo-Shnaf, Reham I A; De Moraes, Gilberto J
The present paper refers to the identification of phytoseiid specimens newly collected by the first author of this paper and her collaborators, as well as to the examination of type specimens of species previously described from Egypt. The taxonomy of phytoseiid mites has been studied in Egypt since 1967. Until now, 78 nominal species have been recorded, of which 60 are valid. One of those species, Phytoseius plumifer (Canestrini & Fanzago), appears to be based on an incorrect record. An additional species (Typhlodromus hellei Hassan, Afifi & Nawar), described from Egypt, is not sufficiently characterised to allow its correct generic classification and the determination of its validity. Eight new records are reported in this paper, including two new species, Proprioseiopsis ismailiaensis n. sp. and Typhlodromus (Anthoseius) fayoumensis n. sp., which are described. Complementary descriptions of 11 known species are given. An updated survey of all species reported from Egypt and a taxonomic key to separate them are also presented. Six new synonymies are proposed.
Walzer, Andreas; Schausberger, Peter
We studied developmental plasticity under food stress in three female-biased size dimorphic predatory mite species, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni. All three species prey on two-spotted spider mites but differ in the degree of adaptation to this prey. Phytoseiulus persimilis is a specialized spider mite predator, N. californicus is a generalist with a preference for spider mites, and A. andersoni is a broad generalist. Immature predators were offered prey patches of varying density and their survival chances, dispersal tendencies, age and size at maturity measured. Amblyseius andersoni dispersed earlier from and had lower survival chances in low density prey patches than N. californicus and P. persimilis. Age at maturity was not affected by prey density in the generalist A. andersoni, whereas both the specialist P. persimilis and the generalist N. californicus accelerated development at low prey densities. Species-specific plasticity in age at maturity reflects opposite survival strategies when confronted with limited prey: to prematurely leave and search for other food (A. andersoni) or to stay and accelerate development (P. persimilis, N. californicus). In all species, size at maturity was more plastic in females than males, indicating that males incur higher fitness costs from deviations from optimal body size.
Jeyaprakash, Ayyamperumal; Hoy, Marjorie A
The genome size of the phytoseiid Metaseiulus (=Typhlodromus or Galendromus) occidentalis (Nesbitt) needs to be estimated before the whole nuclear genome can be sequenced. Two different procedures were used to estimate the genome size of M. occidentalis; (1) flow cytometry (Marescalchi et al. in Genome 33:789-793, 1990) and (2) quantitative real-time PCR (qRT-PCR) (Wilhelm et al. in Nucleic Acids Res 31:e56, 2003). Fluorescence intensity of propidium iodide-stained nuclei of M. occidentalis was measured by flow cytometry using females, males, and eggs. Only the eggs yielded peaks, which ranged in size from 35 to 160 Mb, with a tall peak of 140 Mb in 1-day-old eggs and 65 Mb in 2-day-old eggs, respectively. However, the peaks are broad and do not provide an accurate estimate. The qRT-PCR procedure required single-copy nuclear gene sequences from this phytoseiid. This was accomplished by designing degenerate primers, amplifying the Actin and EF1alpha sequences from M. occidentalis, and then designing M. occidentalis-specific primers that amplified a unique sequence. The standard qRT-PCR protocol was inefficient and amplification failed frequently, so we developed a high-fidelity qRT-PCR protocol, which utilizes a mix of two DNA polymerases (Taq and a proof-reading Tgo or ACCUZYME) to consistently amplify sequences. This allowed us to estimate the nuclear genome size of M. occidentalis as 88-90 +/- 5 Mb. When compared to other arthropod genomes, this appears to be very small.
Castagnoli, M; Simoni, S; Nachman, G
Short-term effects on consumption and oviposition rates of four strains of Neoseiulus californicus (McGregor) after a diet shift were evaluated. The new feeding conditions experienced by the predators were six fixed densities of eggs or protonymphs of Tetranychus urticae Koch placed on excised strawberry leaflet discs and maintained under laboratory conditions (25 +/- 1 degrees C, 75-85% RH, 16L: 8D). The observations were made on the first and the fifth day of the experiment. The phytoseiids came from three long-term mass-reared strains fed on T. urticae, Dermatophagoidesfarinae Hughes, or Quercus spp. pollen, respectively. The fourth strain was collected directly in a strawberry field. Time since diet transfer can be added to the factors (i.e. feeding history and prey density) already known to affect the functional and numerical responses of N. californicus, both when it feeds on prey eggs and protonymphs. If consumption rates were averaged over all strains and densities, 9.04 and 11.41 eggs, and 6.97 and 6.48 protonymphs were consumed on the first and the fifth day, respectively. If the same was done for oviposition rates, predators feeding on eggs produced 1.46 and 2.36 eggs/female/day, whereas predators feeding on protonymphs produced 1.35 and 2.29 eggs/female/day. Time had the greatest impact on the functional response of the strain that had previously fed on tetranychids, while an effect of time on the numerical response was detectable in all strains.
A new stackable modular system was developed for continuous in-vivo production of phytoseiid mites. The system consists of cage units that are filled with lima bean, Phaseolus lunatus, or red beans, P. vulgaris, leaves infested with high levels of the two-spotted spider mites, Tetranychus urticae. T...
Xu, Xuenong; Enkegaard, Annie
The prey preference of polyphagous predators plays an important role in suppressing different species of pest insects. In this study the prey preference of the predatory mite, Amblyseius swirskii (Athias-Henriot) (Acari: Phytoseiidae) was examined between nymphs of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and first instar larvae of the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), as well as between active and chrysalis spider mite protonymphs and active and chrysalis spider mite deutonymphs. The study was done in the laboratory on bean leaf discs at 25 ± 1° C and 70 ± 5% RH. Amblyseius swirskii had a clear preference for thrips compared to both spider mite protonymphs and deutonymphs. About twice as many thrips as spider mites were consumed. Amblyseius swirskii did not show a preference between active and chrysalis stages of spider mites. PMID:21070175
Rahman, Vattakandy jasin; Babu, Azariah; Roobakkumar, Amsalingam; Perumalsamy, Kandasamy
Functional and numerical responses of the predatory mite, Neoseiulus longispinosus (Evans) (Acari: Phytoseiidae) to the red spider mite, Oligonychus coffeae Nietner (Acari: Tetranychidae), infesting tea were determined in a laboratory on leaf discs. Prey consumption increased with increases in temperature and prey density. Handling time decreased and successful attack rate increased with increased temperature. N. longispinosus was more voracious on larvae and nymphs than on adults of O. coffeae. Handling time was higher on adult females than on larvae. Rate of predation leveled off at temperatures greater than 25° C. Functional responses to prey density at six temperatures and to each life stage of O. coffeae approximated the Holling type II model. The oviposition rate increased with prey consumption and temperature. On average, a predator consumed 1.62 adult female prey for every egg it laid. With a fixed number of prey available, predation rate per predator decreased with increased predator density. PMID:23452011
Feather mites (Acari: Astigmata) were analyzed with low temperature scanning electron microscopy (LT-SEM), including the description of three new species: Plicatalloptes atrichogynus sp. nov. (Analgoidea: Alloptidae) from the Neotropical cormorant Phalacrocorax brasilianus (Gmelin, 1789) (Pelecanifo...
Navajas, M; Lagnel, J; Fauvel, G; de Moraes, G
Preliminary work is needed to assess the usefulness of different markers at different taxonomic scales when a new group is analyzed, such as the commercially important Phytoseiidae mites. We investigate here the level of sequence variation of the nuclear ribosomal spacers ITS 1 and 2 and the 5.8S gene in six species of Phytoseiidae: Neoseiulus culifornicus, N. fallacis, Euseius concordis, Metaseiulus occidentalis, Typhlodromus pyri and Phytoseiulus persimilis. As expected, the 5.8S gene (148 base pairs) is markedly conserved and displays little variation in between genera comparisons. ITS1 and ITS2 show contrasting patterns: while the ITS2 is short (80-89 bp) and shows little variation, the ITS1 is longer (303-404 bp) and is very variable in sequence. This fact compromises reliable nucleotide homologies when comparing the genera. The comparison of ITS1 sequence similarity at the species level might be useful for species identification, however, the value of ITS in taxonomic studies does not extend to the level of the family. The intraspecific variations of ITS were investigated in three species: N. californicus, N. fallacis and E. concordis. The first species has identical ITS1 sequences and the last two display low polymorphism (2 nucleotide substitutions). The ITS2 and 5.8S sequences were identical in all three subspecies comparisons.
Gotoh, Tetsuo; Moriya, Daisuke; Nachman, Gösta
The objective of this study was to investigate whether four spider mite species, Tetranychus ludeni, T. phaselus, T. piercei and T. truncatus, currently with insignificant economic impact, have the potential to achieve the same status as T. urticae, which until now has been considered as the most serious tetranychid pest species in orchards and greenhouses. We investigated the effect of temperature on development, survival and oviposition at 11 constant temperatures ranging from 15 to 40 °C at intervals of 2.5 °C and estimated demographic parameters, such as the intrinsic rate of natural increase (rm), for these five species at five constant temperatures. Developmental time from egg to adult (female and male) decreased with increasing temperature from 15 to 32.5 °C in all five species, but increased slightly at 35 °C or higher, especially in T. ludeni and T. urticae. Using linear and non-linear developmental rate models, the lower thermal thresholds for egg-to-adult (female and male) and egg-to-egg development were found to range from 9.8 to 11.7 and from 9.8 to 11.4 °C, respectively. The intrinsic optimal temperature (TΦ) ranged from 18.0 to 27.4 °C for egg-to-female adult and from 23.9 to 27.2 °C for egg-to-egg development. The oviposition period and adult longevity were strongly affected by temperature. The rm-values increased with increasing temperature from 15 to 30 or 35 °C in all five species. The highest rm-values at each temperature were 0.114 day(-1) at 15 °C for T. ludeni, 0.199 day(-1) at 20 °C for T. urticae, 0.314 day(-1) at 25 °C for T. ludeni, 0.451 day(-1) at 30 °C for T. ludeni and 0.433 day(-1) at 35 °C for T. truncatus. The total fecundity, net reproductive rate (R0) and rm of T. ludeni were higher than those of T. urticae at all temperatures. T. piercei and T. truncatus showed higher rm-values at 30 and 35 °C than T. urticae. The results indicate that the former three species are better adapted to hot weather than T. urticae and have a high potential to become serious pests.
The temporal development of biological control of arthropod pests in perennial cropping systems is largely unreported. In this study, the development of biological control of twospotted spider mite, Tetranychus urticae Koch and hop aphid, Phorodon humuli (Schrank) in a new planting of hop in Oregon...
The twospotted spider mite, Tetranychus urticae Koch, is a worldwide pest of numerous agronomic and horticultural plants. Sulfur fungicides are known to induce outbreaks of this pest on several crops, although mechanisms associated with sulfur-induced mite outbreaks are largely unknown. Studies were...
Lara, Jesus R; Hoddle, Mark S
Oligonychus perseae Tuttle, Baker, & Abatiello is a foliar pest of 'Hass' avocados [Persea americana Miller (Lauraceae)]. The recommended action threshold is 50-100 motile mites per leaf, but this count range and other ecological factors associated with O. perseae infestations limit the application of enumerative sampling plans in the field. Consequently, a comprehensive modeling approach was implemented to compare the practical application of various binomial sampling models for decision-making of O. perseae in California. An initial set of sequential binomial sampling models were developed using three mean-proportion modeling techniques (i.e., Taylor's power law, maximum likelihood, and an empirical model) in combination with two-leaf infestation tally thresholds of either one or two mites. Model performance was evaluated using a robust mite count database consisting of >20,000 Hass avocado leaves infested with varying densities of O. perseae and collected from multiple locations. Operating characteristic and average sample number results for sequential binomial models were used as the basis to develop and validate a standardized fixed-size binomial sampling model with guidelines on sample tree and leaf selection within blocks of avocado trees. This final validated model requires a leaf sampling cost of 30 leaves and takes into account the spatial dynamics of O. perseae to make reliable mite density classifications for a 50-mite action threshold. Recommendations for implementing this fixed-size binomial sampling plan to assess densities of O. perseae in commercial California avocado orchards are discussed.
Humeres, Eduardo C; Morse, Joseph G
Persea mite, Oligonychus perseae Tuttle, Baker, and Abatiello, susceptibility to abamectin and milbemectin was evaluated in 2003 to determine baseline susceptibility levels in avocado groves in San Diego and Ventura Counties (California, USA) where more than 70% of the state's avocado production is concentrated. Milbemectin has yet to be used in avocado production in California and abamectin has been available for use since 1999. Baseline susceptibility ratios (in relation to the most susceptible population) of five persea mite field strains to milbemectin varied 2.1- to 2.8-fold at the LC50 and LC90, respectively. The susceptibility of seven field strains to abamectin varied slightly more (2.1- to 3.5-fold) with one strain subjected to seven sprays over the past 4 years showing slight but significant separation of LC50 and LC90's from the most susceptible strain, which is suggestive of the early stages of resistance to this product. Based on these data, baseline susceptibility levels are proposed that might be used to monitor for future persea mite resistance to these chemicals as their use in California avocado production continues.
Uesugi, R; Goka, K; Osakabe, Mh
We studied the genetic basis of resistance to two new acaricides, chlorfenapyr and etoxazole, which have different chemical structures and modes of action in the two-spotted spider mite, Tetranychus urticae Koch. The resistance ratios calculated from the LC50s of resistant and susceptible strains were 483 for chlorfenapyr and >100,000 for etoxazole. Mortality caused by the two acaricides in F1 progeny from reciprocal crosses between the resistant and susceptible strains indicated that the modes of inheritance of resistance to chlorfenapyr and etoxazole were completely dominant and completely recessive, respectively. Mortality in F2 progeny indicated that for both acaricides, the resistance was under monogenic control. Repeated backcross experiments indicated a linkage relationship among the two acaricide resistances and malate dehydrogenase, although phosphoglucoisomerase was not linked with them. The recombination ratio between the resistances was 14.8%. From this result, we suggest that heavy spraying of the two acaricides will lead to apparent cross-resistance as a consequence of crossing over; the two resistance genes are so close to each other that it would be difficult to segregate them once they came together on the same chromosome.
Herron, G A; Rophail, J
Chlorfenapyr resistance (2.9- and 19.9-fold respectively at LC50 and LC99 level) was detected in Tetranychus urticae Koch causing control failure following a single application of product to nectarines.
Tang, Xiaofeng; Zhang, Youjun; Wu, Qingjun; Xie, Wen; Wang, Shaoli
The two-spotted spider mite, Tetranychus urticae Koch, is a worldwide crop pest. The resistance to commonly applied acaricides (in this report, "acaricide" refers to both acaricides and insecticides that are toxic to mites) has seriously impaired T. urticae control in the field. Here, the sensitivity of eggs, larvae, and adults of laboratory and field populations of T. urticae to various acaricides was investigated. Based on data obtained with an acaricide-sensitive laboratory strain collected in 2009, abamectin was the most toxic of the tested acaricides. For each acaricide, susceptibility was greatest for larvae, least for adults, and intermediate for eggs. The egg was the most sensitive stage to abamectin, bifenazate, and hexythiazox; the larva was the most sensitive stage to abamectin, hexythiazox, bifenazate, propargite, and chlorfenapyr; and the adult was the most sensitive stage to abamectin, bifenazate, and chlorfenapyr. Based on the results obtained with the acaricide-sensitive laboratory strain, acaricides were selected to test against eggs, larvae, and adults of four field populations of T. urticae from Beijing, China. Although the field populations differed in their resistance to the acaricides in laboratory bioassays, the eggs, larvae, and adults of the four populations were sensitive to bifenazate and highly resistant to abamectin. Field trials for control of T. urticae in Beijing, China, should be conducted with bifenazate and other acaricides rather than with abamectin.
We verified infestation of Oligonychus milleri (McGregor) on plantations of Pinus caribaea (Pinaceae) and of Oligonychus ununguis (Jacobi) on plantations of Eucalyptus urophylla x Eucalyptus grandis (Myrtaceae) in State of Rondônia, Northern region of Brazil. This represents the first record of O. m...
Shi, Wei-Bing; Feng, Ming-Guang; Liu, Shu-Sheng
Aerial conidia of Beauveria bassiana in an emulsifiable formulation germinated by >95% after 24 h exposure to the regimes of 20, 25 and 30 degrees C with 51%, 74% and 95% RH. Ovicidal activities of the formulation towards two-spotted spider mite, Tetranychus urticae, were assayed at the concentrations of 0, 18, 160 and 693 conidia mm(-2) sprayed separately onto fava bean leaves including 39 (25-76) eggs per capita. All the sprayed eggs on the leaves were directly exposed to the different regimes for hatch after 24 h maintenance in covered Petri dishes. Generally, hatched proportions increased over post-spray days and decreased with the elevated fungal concentrations; no more eggs hatched from day 9 or 10 onwards. Based on the counts of the hatched/non-hatched eggs in the different regimes, the final egg mortalities were 15.0-40.4%, 48.9-66.6% and 62.9-87.5% at the low, medium and high concentrations, respectively, but only 5.6-11.3% in blank controls. The RH effect on the fungal action was significant at 20 and 25 degrees C but not at 30 degrees C whereas the effect of temperature was significant at 51% and 74% RH but not at 95% RH. Probit analysis of the egg mortalities versus the fungal sprays generated median lethal concentrations (LC(50)) of 65-320 conidia mm(-2) at all the regimes, and of only 65-78 conidia mm(-2) at 25-30 degrees C with 74-95% RH. The results highlight ovicidal activities of the emulsifiable formulation against the mite species at the tested regimes and its potential use in spider mite control.
Phytophagous mites and endophytic fungi may interact when sharing a host plant, potentially influencing one another’s growth or population dynamics; however, interactions between them are poorly known and remain largely unexplored. In this study, quantitative associations between three species of ph...
Alatawi, F J; Opit, G P; Margolies, D C; Nechols, J R
The twospotted spider mite, Tetranychus urticae Koch, is an important pest of impatiens, a floricultural crop of increasing economic importance in the United States. The large amount of foliage on individual impatiens plants, the small size of mites, and their ability to quickly build high populations make a reliable sampling method essential when developing a pest management program. In our study, we were particularly interested in using spider mite counts as a basis for releasing biological control agents. The within-plant distribution of mites was established in greenhouse experiments and these data were used to identify the sampling unit. Leaves were divided into three zones according to location on the plant: inner, intermediate, and other. On average, 40, 33, and 27% of the leaves belonged to the inner, intermediate, and other leaf zones, respectively. However, because 60% of the mites consistently were found on the intermediate leaves, intermediate leaves were chosen as the sampling unit. These results lead to the development of a presence-absence sampling method for T. urticae by using Taylor coefficients generic for this pest. The accuracy of this method was verified against an independent data set. By determining numerical or binomial sample sizes for consistently estimating twospotted spider mite populations, growers will now be able to determine the number of predatory mites that should be released to control twospotted spider mites on impatiens.
Two-spotted spider mite (TSSM), Tetranychus urticae (Koch), is an early season pest of cotton in the mid-southern United States and causes reduction in yield, fiber quality and impaired seed germination. Objectives of this study were to investigate the efficacy of abamectin and spiromesifen with two...
Two-spotted spider mite (TSSM), Tetranychus urticae Koch, feeds on epidermal cells of cotton foliage, destroys photosynthetic cells, and reduces yields, fiber quality and seed germination. With a short life cycle, prolific fecundity, an arrhenotokous reproduction, and an ability to expeditiously dig...
Van Leeuwen, T; Dermauw, W; van de Veire, M; Tirry, L
Spinosad is a reduced-risk insecticide derived as a fermentation product from the soil actinomycete Saccharopolyspora spinosa. It is toxic by ingestion and contact and has a unique mode of action on the insect nervous system. Spinosad exhibits a high degree of selective toxicity towards the insect orders Lepidoptera, Diptera and Thysanoptera, but is less toxic to many beneficial arthropods. To determine if spinosad could be valuable as an alternative acaricide for the control of Tetranychus urticae, laboratory toxicity experiments with leaf-disk bio-assays were performed on a laboratory susceptible and several resistant strains. LC50 values were rather high in comparison with newly developed commercial acaricides. Surprisingly, when spinosad was applied to the roots of tomato plants in rock wool, excellent control of spider mites was obtained. Apparently, spinosad has systemic properties and quantities as low as 1 mg/plant could protect tomato plants from mite infestation. Different substrates with varying percentage of clay and organic matter were tested in comparison with rockwool and showed that sufficient control was restricted to the rockwool substrate. Consequently, a dose-response experiment with tomato plants grown in rockwool was set up. The persistence of spinosad toxicity when applied via the roots was determined, and pointed to a long lasting control (up to 30 DAT). Spinosad amounts in leaves after systemic application were determined with an immunological technique to quantify spinosad uptake. Correlations between mite control, spinosad uptake and leaf concentrations can be helpful to determine the necessary dose in field situations.
Fraulo, Aimee B; Cohen, Matthew; Liburd, Oscar E
The twospotted spider mite, Tetranychus urticae Koch, is among the most economically important pests in strawberries (Fragaria spp.). As T. urticae feeds, it ingests mesophyll cells that contain pigments essential for physiologic function and alters radiant energy use of the leaf tissue, severely compromising plant health and productivity. In our study, diffuse reflectance spectroscopy in the visible and near infrared (VNIR) portions of the spectrum was used to identify specific spectral regions altered by T. urticae feeding and to quantitatively assess T. urticae density. During the 2006-2007 growing season, 80 strawberry leaflets with varying levels of T. urticae infestation were collected. Spectral classification of both mite density (continuous) and mite density class (categorical) were developed. Spider mite density classes were low infestation (0-20 mites/leaflet), moderate infestation (20-50 mites/leaflet), and high infestation (> or = 50 mites/leaflet). Continuous spectral prediction for leaf infestation was developed using partial least squares (PLS) regression. Classification trees were used to train spectra to categorical levels of infestation. Both models were calibrated with 67% of the samples, and accuracy was evaluated using the remaining 33%. Categorical validation accuracy was 81%, with odds ratios for correctly predicting extreme categories (low and high) of 33 and 47.7, respectively. Continuous validation efficiency was also high, with an r2 between predicted and observed of 0.85 and a root-mean-squared error (RMSE) of 12.2 mites per leaf. Developing a spectral pest monitoring system would provide a diagnostic tool allowing early and effective intervention for precision management of T. urticae in strawberry.
Castro, E B; Zanardi, O C; Garlet, J; Ochoa, R; Feres, R J F
We verified infestation of Oligonychus milleri (McGregor) on plantations of Pinus caribaea (Pinaceae) and of Oligonychus ununguis (Jacobi) on plantations of Eucalyptus urophylla x Eucalyptus grandis (Myrtaceae) in State of Rondônia, Northern region of Brazil. This represents the first record of O. milleri in Brazil. Oligonychus ununguis was recorded previously, on cypress. The damage caused by these two spider mites in the plantations is described herein.
Prado, Julia; Quesada, Carlos; Gosney, Michael; Mickelbart, Michael V; Sadof, Clifford
Although leaf nitrogen (N) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to N fertilization on susceptible and resistant host plants are not well characterized. This study determined how different rates of N fertilization affected injury caused by the potato leafhopper (Empoasca fabae Harris) and the abundance of maple spider mite (Oligonychus aceris (Shimer)) on 'Red Sunset' red maple (Acer rubrum) and 'Autumn Blaze' Freeman maple (Acer×freemanii) during two years in Indiana. N fertilization increased leaf N concentration in both maple cultivars, albeit to a lesser extent during the second year of the study. Overall, Red Sunset maples were more susceptible to E. fabae injury than Autumn Blaze, whereas Autumn Blaze maples supported higher populations of O. aceris. Differences in populations of O. aceris were attributed to differences between communities of stigmaeid and phytoseiid mites on each cultivar. Injury caused by E. fabae increased with N fertilization in a dose-dependent manner in both cultivars. Although N fertilization increased the abundance of O. aceris on both maple cultivars, there was no difference between the 20 and 40 g rates. We suggest the capacity of N fertilization to increase O. aceris on maples could be limited at higher trophic levels by the community of predatory mites.
Shibuya, T; Itagaki, K; Ueyama, S; Hirai, N; Endo, R
We investigated the effects of morphology of host cucumber, Cucumis sativus L., leaves acclimatized to different atmospheric humidity levels on oviposition by adult females of the twospotted spider mite, Tetranychus urticae Koch. Cucumber seedlings were grown at a vapor pressure deficit (VPD) of 0.4, 1.9, or 3.0 kPa at 28°C (90%, 50%, or 20% relative humidity, respectively) in growth chambers until the second true leaves had expanded. Adult females of T. urticae were released on the adaxial surfaces of leaf squares cut from first and second true leaves in each treatment group, and held in the same humidity condition. Eggs were counted 2 d after release. The lower acclimatization humidity (higher VPD) increased trichome (leaf hair) density of the host leaves and oviposition rate, but the relationship between the trichome and oviposition differed between leaf positions. The leaf mass per area (LMA) was greater in first true leaves than in second true leaves, but was not influenced by VPD. A linear regression model with oviposition rate as the dependent variable and trichome density and LMA as independent variables showed that both variables influenced the oviposition rate approximately equally. We conclude that oviposition was accelerated under low humidity (high VPD) conditions indirectly probably through an increase in the trichome density of host leaves.
Phytophagous mites and endophytic fungi may interact when sharing a host plant, potentially influencing one another’s growth or population dynamics; however, interactions between them are poorly known and remain largely unexplored. In this study, quantitative associations between three species of ph...
Guzman-Valencia, Stephanie; Santillán-Galicia, Ma Teresa; Guzmán-Franco, Ariel W; Vega-Muñoz, Ricardo
Adaptation to different host plants can lead to host-associated differentiation (HAD). The mites Oligonychus perseae and Oligonychus punicae have a broad range of host plants, but, to date, records of them coexisting sympatrically had only been reported on avocado. However, our field observations showed both species coexisting on host plants other than avocado. The lack of previous records of these mites on the host plants studied here suggests only recent divergence to new host plant species. Previous studies showed that O. punicae had a limited migration capacity compared with O. perseae, suggesting that O. punicae is more likely to develop a close host plant relationship leading to HAD. Adults of both species were collected from trees hosting both mite species. Three genera of host plants considered were Persea, Salix, and Alnus; two species within one genus were Alnus jorullensis and Alnus acuminata; and three varieties within one species were Persea americana var. Fuerte, var. Hass, and var. Criollo, a noncommercial variety. Using sequence data from a segment of the mitochondrial cytochrome oxidase subunit I, the phylogenetic relationships and genetic population structure of both mite species in relation to the host plant were determined. Oligonychus perseae populations showed a significant population structure in relation to host plant at the species and genus level, but there was no effect of variety. In contrast, host plant explained none of the genetic variation among O. punicae populations. The potential role of coexistence mechanisms in the contrasting genetic population structure of both mite species is discussed. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Nyoike, Teresia W; Liburd, Oscar E
Understanding the impact of a pest species on a particular crop is critical for the success of a pest management program. Field studies were conducted to determine the effect of the twospotted spider mite, Tetranychus urticae Koch, on marketable yield of strawberries during the 2008/2009 and 2009/2010 growing seasons. Low, medium, and high mite infestation levels were established by initial inoculations of5, 10, and 20 twospotted spider mites per strawberry leaf, respectively. A control treatment maintained at near zero mites through applications of an acaricide, bifenazate (Acramite 50 WP), was also included. Weekly records of motile twospotted spider mites were obtained over 13 and 16 wk during the 2008/2009 and 2009/2010 growing seasons, respectively. Degree-days and weather parameters were monitored to determine their effect on mite population. In addition, mite-days were calculated for each year from weekly mite counts to determine the effect of mites on marketable yield of strawberries. In both years, twospotted spider mite population increased throughout the growing seasons. More degree-days were accumulated during the 2008/2009 growing season, and mite population was higher in 2008/2009 than in 2009/2010. Mite population density per leaf increased up to 278 motiles per leaf in 2008/2009 growing season as compared with 137 in 2009/2010 within the high-infestation-level treatment. The divergence in mite population between the two growing seasons was attributed mainly to temperature differences between the two seasons that affected mite population development and establishment. During both growing seasons, the high mite infestation level had lowest marketable yield. A negative correlation between cumulative mite-days and harvested marketable yields was detected in both seasons, but it was only significant during the 2008/2009 growing season. Strawberry yield reduction was detected when plants attained 80 mites per leaf in 2008/2009 and 50 mites per leaf in 2009/2010 within the high mite infestation treatment. Factors that affect mite population establishment and management for twospotted spider mites on strawberries are discussed.
Liu, Ruohan; Nyoike, Teresia W; Liburd, Oscar E
Greenhouse and field experiments were conducted to evaluate the effectiveness of site-specific tactics for management of the twospotted spider mite, Tetranychus urticae Koch, a major pest of greenhouse and field-grown strawberries (Fragaria x ananassa Duchesne). Two site-specific (spot) treatments, the miticide bifenazate (Acramite(®)) and the predatory mite Neoseiulus californicus McGregor, were compared with whole-plot treatments of bifenazate or N. californicus to determine whether T. urticae could be effectively managed in field-grown strawberry using only site-specific tactics. Additionally, the cost of site-specific tactics was compared with whole-plot treatments to determine the economic value of using site-specific management tactics for T. urticae in strawberries. In the greenhouse, all treatments equivalently reduced the number of T. urticae below control. In the field during the 2011-2012 season, more T. urticae eggs and motiles were in the whole-plot treatments of both N. californicus and bifenazate in the mid-season and late season, respectively, compared with the spot treatments. With the exception of site-specific N. californicus during the 2011-2012 field season, there were no differences in marketable yields between plots with site-specific treatments and whole-plot management. An economic analysis demonstrated a significant cost savings (75.3 %) with site-specific treatments of N. californicus compared with whole-plot application of N. californicus. Similarly, a 24.7 % reduction in cost was achieved in using site-specific bifenazate compared with whole-plot application of bifenazate. The findings indicate that site-specific treatments with N. californicus and bifenazate are competitive alternatives to whole-field application for T. urticae management in strawberries.
Liu, Bin; Jiang, Gaofei; Zhang, Yunfei; Li, Junli; Li, Xiaojiao; Yue, Jiansu; Chen, Fei; Liu, Haoqiang; Li, Hongjun; Zhu, Shiping; Wang, Jinjun; Ran, Chun
Background The citrus red mite is a worldwide citrus pest and a common sensitizing allergen of asthma and rhinitis. It has developed strong resistance to many registered acaricides, However, the molecular mechanisms of resistance remain unknown. we therefore used next generation sequencing technology to investigate the global transcriptomes between resistant strains and susceptible strains. Results We obtained 34,159, 30,466 and 32,217 unigenes by assembling the SS reads, RS reads and SS&RS reads respectively. There are total 17,581 annotated unigenes from SS&RS reads by BLAST searching databases of nr, the Clusters of Orthologous Groups (COGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) with an E-value ≤ 1e-5, in which 7,075 unigenes were annotated in the COG database, 12, 712 unigenes were found in the KEGG database and 3,812 unigenes were assigned to Gene ontology (GO). Moreover, 2,701 unigenes were judged to be the differentially expressed genes (DEGs) based on the uniquely mapped reads. There are 219 pathways in all annotated unigenes and 198 pathways in DEGs that mapped to the KEGG database. We identified 211 metabolism genes and target genes related to general insecticide resistance such as P450 and Cytochrome b, and further compared their differences between RS and SS. Meanwhile, we identified 105 and 194 genes related to growth and reproduction, respectively, based on the mode of action of Hexythiazox. After further analyses, we found variation in sequences but not in gene expression related to mite growth and reproduction between different strains. Conclusion To our knowledge, this is the first comparative transcriptome study to discover candidate genes involved in phytophagous mite resistance. This study identified differential unigenes related to general pesticide resistance and organism growth and reproduction in P. citri. The assembled, annotated transcriptomes provide a valuable genomic resource for further understanding the molecular basis of resistance mechanisms. PMID:22162774
Woods, J L; Dreves, A J; Fisher, G C; James, D G; Wright, L C; Gent, D H
The twospotted spider mite, Tetranychus urticae Koch, is a worldwide pest of numerous agronomic and horticultural plants. Sulfur fungicides are known to induce outbreaks of this pest on several crops, although mechanisms associated with sulfur-induced mite outbreaks are largely unknown. Studies were conducted during 2007-2009 in Oregon and Washington hop yards to evaluate the effect of timing of sulfur applications on T. urticae and key predators. In both regions, applications of sulfur made relatively late in the growing season (mid-June to mid-July) were associated with the greatest exacerbation of spider mite outbreaks, particularly in the upper canopy of the crop. The severity of mite outbreaks was closely associated with sulfur applications made during a relatively narrow time period coincident with the early exponential phase of spider mite increase and rapid host growth. A nonlinear model relating mean cumulative mite days during the time of sulfur sprays to the percent increase in total cumulative mite days (standardized to a nontreated plot) explained 58% of the variability observed in increased spider mite severity related to sulfur spray timing. Spatial patterns of spider mites in the Oregon plots indicated similar dispersal of motile stages of spider mites among leaves treated with sulfur versus nontreated leaves; however, in two of three years, eggs were less aggregated on leaves of sulfur-treated plants, pointing to enhanced dispersal. Apart from one experiment in Washington, relatively few predatory mites were observed during the course of these studies, and sulfur-induced mite outbreaks generally occurred irrespective of predatory mite abundance. Collectively, these studies indicate sulfur induces mite outbreaks through direct or indirect effects on T. urticae, mostly independent of predatory mite abundance or toxicity to these predators. Avoidance of exacerbation of spider mite outbreaks by sulfur sprays was achieved by carefully timing applications to periods of low spider mite abundance and slower host development, which is generally early to mid-spring for hop.
Le Goff, Guillaume Jean; Hance, Thierry; Detrain, Claire; Deneubourg, Jean-Louis; Mailleux, Anne-Catherine
The two-spotted spider mite Tetranychus urticae is a silk producer known to live in groups with a common silk web that can cover entire plants and protect mites against predators, rain and wind. Silk also plays an important role during collective migration by aerial dispersal or by walking. In this context, we studied the locomotor activity i.e. time in movement, in resting, and in static exploration (probing behaviour) of an individual confronted to clean places and/or places covered by silk coming from its own population or from another. Two populations were tested, one of the red form (Tunisia) and another of the green form (Belgium). The experimental results showed that the presence or the absence of silk did not influence the relative proportion of each behavioural item either for the red or the green population. Individuals of the green form population spent more time moving and less time resting than individuals of the red form population and this, whatever the substrate (red/green silk, clean). Moreover, the silk from the red form population attracted individuals from both populations, whereas the silk produced by the green form population did not attract any individual either from the red or the green form. This surprising result might have been due to a difference in the quantity and/or quality of silk woven by the two forms. We discuss how the differences observed in the behaviour of these two populations may result from differences in their strategy to rapidly increase the population of the colony and reinforce the silk nest. Copyright © 2012 Académie des sciences. Published by Elsevier SAS. All rights reserved.
Marčić, Dejan; Međo, Irena
Lethal and sublethal effects of the biopesticide Kingbo (oxymatrine 0.2 % + psoralen 0.4 %) on the two-spotted spider mite (Tetranychus urticae Koch) were investigated in laboratory bioassays. The biopesticide was applied to bean leaf discs or primary leaves by using a Potter spray tower. Acute toxicity tests showed no significant ovicidal action: toxic effect (LC50 = 55.49 μl/l) was the result of a residual activity against larvae that hatched from the treated eggs. Preovipositional females and female teleiochrysales showed similar susceptibility (LC50 = 52.68 and 59.03 μl/l, respectively), whereas larvae, protonymphs and female deutonymphs were the most susceptible stages (LC50 = 6.88, 13.03, and 8.80 μl/l, respectively). In a choice test, females preferred the untreated halves of leaves over the halves treated with 2,000, 1,000, and 500 μl/l in the first 24 h, and their oviposition in those treatments was significantly greater on the untreated halves after 24 and 48 h, as well as the summed oviposition over 72 h. Viability and reproduction of survivors, as well as population growth, were strongly affected after the treatments of preovipositional females and female teleiochrysales with 100, 50 and 25 μl/l. On the other hand, sublethal effects on the females that survived treatment at the egg stage or reached adulthood from the eggs laid on the treated surface (treatments with 50 and 25 μl/l) were significantly weaker. Acaricidal and sublethal effects of the biopesticide Kingbo were discussed as a starting point for further research aimed to improve management of T. urticae populations. Regulatory issues and safety concerns regarding further commercialization of this biopesticide are addressed as well.
Alves, Sérgio Batista; Rossi, Luciana Savoi; Lopes, Rogério Biaggioni; Tamai, Marco Antonio; Pereira, Roberto M
Beauveria bassiana colonizes insect hosts initially through a yeast phase, which is common in some artificial liquid cultures, but not reported on artificial solid media. We describe a yeast-like phase for B. bassiana isolate 447 (ATCC 20872) on MacConkey agar and its virulence toward Diatraea saccharalis and Tetranychus urticae. The yeast-like cells of B. bassiana developed by budding from germinating conidia after 24-h incubation. Cells were typically 5-10 microm and fungal colonies were initially circular and mucoid, but later were covered with mycelia and conidia. Ability to produce yeast-like cells on MacConkey medium was relatively common among different B. bassiana isolates, but growth rate and timing of yeast-like cell production also varied. Metarhizium anisopliae and Paecilomyces spp. isolates did not grow as yeast-like cells on MacConkey medium. Yeast-like cells of B. bassiana 447 were more virulent against D. saccharalis than conidia when 10(7)cells/ml were used. At 10(8)cells/ml, the estimated mean survival time was 5.4 days for the yeast suspension and 7.7 days for the conidial suspension, perhaps due to faster germination. The LC(50) was also lower for yeast than conidial suspensions. Yeast-like cells and conidia had similar virulence against T. urticae; the average mortalities with yeast-like cells and conidia were, respectively, 42.8 and 45.0%, with 10(7)cells/ml, and 77.8 and 74.4%, with 10(8)cells/ml. The estimated mean survival times were 3.6 and 3.9 for yeast and conidial suspensions, respectively. The bioassay results demonstrate the yeast-like structures produced on MacConkey agar are effective as inoculum for B. bassiana applications against arthropod pests, and possibly superior to conidia against some species. Obtaining well-defined yeast phase cultures of entomopathogenic hyphomycetes may be an important step in studies of the biology and nutrition, pathogenesis, and the genetic manipulation of these fungi.
Meynard, Christine N; Migeon, Alain; Navajas, Maria
Many species are shifting their distributions due to climate change and to increasing international trade that allows dispersal of individuals across the globe. In the case of agricultural pests, such range shifts may heavily impact agriculture. Species distribution modelling may help to predict potential changes in pest distributions. However, these modelling strategies are subject to large uncertainties coming from different sources. Here we used the case of the tomato red spider mite (Tetranychus evansi), an invasive pest that affects some of the most important agricultural crops worldwide, to show how uncertainty may affect forecasts of the potential range of the species. We explored three aspects of uncertainty: (1) species prevalence; (2) modelling method; and (3) variability in environmental responses between mites belonging to two invasive clades of T. evansi. Consensus techniques were used to forecast the potential range of the species under current and two different climate change scenarios for 2080, and variance between model projections were mapped to identify regions of high uncertainty. We revealed large predictive variations linked to all factors, although prevalence had a greater influence than the statistical model once the best modelling strategies were selected. The major areas threatened under current conditions include tropical countries in South America and Africa, and temperate regions in North America, the Mediterranean basin and Australia. Under future scenarios, the threat shifts towards northern Europe and some other temperate regions in the Americas, whereas tropical regions in Africa present a reduced risk. Analysis of niche overlap suggests that the current differential distribution of mites of the two clades of T. evansi can be partially attributed to environmental niche differentiation. Overall this study shows how consensus strategies and analysis of niche overlap can be used jointly to draw conclusions on invasive threat considering different sources of uncertainty in species distribution modelling.
Musa, Asma; Međo, Irena; Marić, Ivana; Marčić, Dejan
Acaricidal and sublethal effects of the biopesticide Requiem(®)EC (containing an essential oil extract of Chenopodium ambrosioides near ambrosioides) on the two-spotted spider mite, Tetranychus urticae Koch, were evaluated in laboratory bioassays. The biopesticide was applied to bean leaves or leaf discs using a Potter spray tower. Acaricidal activity against eggs and immatures was evaluated in successive acute toxicity bioassays. Concentration-mortality data were subjected to probit analysis and the following LC50 values (ml/l) were calculated: 2.47 (eggs), 0.71 (larvae), 1.13 (protonymphs), 2.23 (female deutonymphs), and 6.02 (female teleiochrysalises). In adult bioassay, in which pre-ovipositional females were treated with a series of concentrations (0.31-10 ml/l), a run-off effect ranging 4-80% (after 24 h) and 8-93% (after 72 h) was observed. In two-choice bioassay, T. urticae females preferred the untreated halves of leaves over the halves treated with 1.25-10 ml/l biopesticide and they laid significantly more eggs on the untreated halves in the first 24 h and summed over 72 h. The indices of repellency and oviposition deterence ranged 11.2-77.3 and 14.8-87.9%, respectively. In age-stage two-sex life table bioassay, the females that hatched from eggs treated with 2.5 ml/l biopesticide and reached adulthood on treated leaf surface showed a significantly reduced the intrinsic rate of increase (r = 0.222), compared to the control (r = 0.317). The reduction of population growth was mainly due to a reduced preadult survival rate (0.42 ± 0.04) and extended juvenile developmental time (9.27 ± 0.11 days), compared to the control (0.93 ± 0.03 and 7.70 ± 0.06 days, respectively).
Le Goff, Guillaume Jean; Hance, Thierry; Detrain, Claire; Deneubourg, Jean-Louis; Mailleux, Anne-Catherine
In many vertebrates and invertebrates, living in a group may influence the life history traits, physiology and behaviour of its individual members, whereas genetic relatedness affects social interactions among individuals in a group. The two-spotted spider mite Tetranychus urticae is characterised by a communal organization, in which silk production plays a key role. A silken web protects the colony against biotic and abiotic agents such as predators, competitors, humidity, wind, rain and acaricides. To evaluate the potential costs and benefits of being associated with genetically distant vs genetically close individuals in T. urticae, we assessed various fitness indicators (faecal pellet production, fecundity, death rate) in pure and mixed groups of two distinct populations of T. urticae: a red-form population from Tunisia and a green-form population from Belgium. If genetic origin had no influence, the values of fitness indicators in mixed groups composed of green and red individuals, would be intermediate between those of the pure green-form and red-form groups. Our results show that in a mixed group, faecal pellet production and death rate were statistically similar to the values obtained in the pure group of green-form individuals. Therefore, our study suggests that strain recognition ability may occur in T. urticae and that the genetic background of an individual may have a great impact on several of its life history traits.
Ullah, M S; Moriya, D; Badii, M H; Nachman, G; Gotoh, T
We investigated the effect of temperature on development and demographic parameters such as the intrinsic rate of natural increase (r (m)) of the two spider mite species Tetranychus merganser Boudreaux and T. kanzawai Kishida at eleven constant temperatures ranging from 15 to 40°C at intervals of 2.5°C. Both male and female T. merganser and T. kanzawai completed development from egg to adult at temperatures ranging from 15 to 37.5°C. The longest developmental duration of immature stages was found at 15°C and the shortest developmental duration was found at 35°C for both species. Using linear and non-linear developmental rate models, the lower thermal thresholds for egg-to-adult (female and male) and egg-to-egg development were estimated as 12.2-12.3°C for T. merganser and as 10.8°C for T. kanzawai. The highest developmental rates were observed at around 35°C, whereas the upper developmental thresholds were around 40°C for both species. In fact, at 40°C, a few eggs of either species hatched, but no larvae reached the next stage. The r (m)-values of T. merganser ranged from 0.072 (15°C) to 0.411 day(-1) (35°C), whereas those of T. kanzawai ranged from 0.104 (15°C) to 0.399 (30°C). The r (m)-values were higher for T. kanzawai than for T. merganser at temperatures from 15 to 30°C, but not at 35°C (0.348 day(-1)). Total fecundity of T. merganser was also higher than that of T. kanzawai at 35°C. These results indicate that higher temperatures favor T. merganser more than T. kanzawai.
Mondal, Sagata; Gupta, Salil Kumar
The present paper reports duration of different developmental stages as well as fecundity, longevity, oviposition periods, sex ratio, etc. of Tetranychus sayedi Baker & Pitchard on two medicinal plants, viz. Cryptolepis buchanani Roem & Schult and Justicia adhatoda L. under laboratory condition at 27.5 °C and 65% R.H. during February-March, 2016. The two hosts in which the life cycle was studied form two new records of hosts for this mite. It appears that C. buchanani is better host among the two hosts as because the life cycle (egg to adult) was completed in shorter time, recording high fecundity and longer longevity.
Ahn, Y J; Kim, Y J; Yoo, J K
The toxicities of the herbicide glufosinate-ammonium to three predatory insect and two predatory mite species of Tetranychus urticae Koch were determined in the laboratory by the direct contact application. At a concentration of 540 ppm (a field application rate for weed control in apple orchards), glufosinate-ammonium was almost nontoxic to eggs of Amblyseius womersleyi Schicha, Phytoseiulus persimilis Athias-Henriot, and T. urticae but highly toxic to nymphs and adults of these three mite species, indicating that a common mode of action between predatory and phytophagous mites might be involved. In tests with predatory insects using 540 ppm, glufosinate-ammonium revealed little or no harm to larvae and pupae of Chrysopa pallens Rambur but was slightly harmful to eggs (71.2% mortality), nymphs (65.0% mortality), and adults (57.7% mortality) of Orius strigicollis Poppius. The herbicide showed no direct effect on eggs and adults of Harmonia axyridis (Pallas) but was harmful, slightly harmful, and harmless to first instars (100% mortality), fourth instars (51.1% mortality), and pupae (24.5% mortality), respectively. The larvae and nymphs of predators died within 12 h after treatment, suggesting that the larvicidal and nymphicidal action may be attributable to a direct effect rather than an inhibitory action of chitin synthesis. On the basis of our data, glufosinate-ammonium caused smaller effects on test predators than on T. urticae with the exception of P. persimilis, although the mechanism or cause of selectivity remains unknown. Glufosinate-ammonium merits further study as a key component of integrated pest management.
Tuan, Shu-Jen; Lin, Yung-Hsiang; Yang, Chung-Ming; Atlihan, Remzi; Saska, Pavel; Chi, Hsin
Tetranychus urticae Koch is a cosmopolitan pest whose rapid developmental rate enables it to produce colonies of thousands of individuals within a short time period. When a solitary virgin female colonizes a new host plant, it is capable of producing male offspring through the arrhenotokous parthenogenesis; once her sons mature, oedipal mating occurs and the female will produce bisexual offspring. To analyze the effect of arrhenotokous reproduction on population growth, we devised and compared separate life tables for arrhenotokous and bisexual populations of T. urticae using the age-stage, two-sex life table theory. For the cohort with bisexual reproduction, the intrinsic rate of increase (r), finite rate (λ), net reproductive rate (R0), and mean generation time (T) were 0.2736 d(−1), 1.3146 d(−1), 44.66 offspring, and 13.89 d, respectively. Because only male eggs were produced during the first 8 d of the oviposition period and the cohort would soon begin bisexual reproduction, it would be theoretically wrong to calculate the population parameters using the survival rate and fecundity of an arrhenotokous cohort. We demonstrated that the effect of arrhenotokous reproduction could be accurately described and evaluated using the age-stage, two-sex life table. We also used population projection based on life table data, quantitatively showing the effect that arrhenotokous reproduction has on the growth potential and management of T. urticae.
Gouvea, Alfredo de; Bertoldo, Guilherme; Alves, Luis F A
Mite infestations to the culture of mate-tea frequently causes losses by the premature fall of the leaves. So, it is necessary to monitor the population of these arthropods, and to adopt management strategies for their control. The objective of this research was to evaluate the trustworthiness of presence-absence sampling for Oligonychus yothersi (McGregor) on mate-tea orchard. This study was conducted in Cascavel, Paraná State, from April 2001 to July 2000, in a mate-tea tree commercial plantation. Biweekly sampling of 240 leaves were collected in different parts of 10 plants, and the number of mites was counted. The aggregation pattern was determined through the coefficients a and b of Taylor's power law. The proportion of infested leaves and the number of required samples were estimated through mathematical model. The mite O. yothersi presented aggregate distribution. The proportion of infested leaves calculated by means of mathematical model showed to be a trustworthy parameter to estimate the population density of the mite. The number of required samples was small, making feasible the practical application of the presence-absence sampling method for O. yothersi in the culture of mate-tea.
Harris, Adrian L; Ullah, Roshan; Fountain, Michelle T
Tetranychus urticae is a widespread polyphagous mite, found on a variety of fruit crops. Tetranychus urticae feeds on the underside of the leaves perforating plant cells and sucking the cell contents. Foliar damage and excess webbing produced by T. urticae can reduce fruit yield. Assessments of T. urticae populations while small provide reliable and accurate ways of targeting control strategies and recording their efficacy against T. urticae. The aim of this study was to evaluate four methods for extracting low levels of T. urticae from leaf samples, representative of developing infestations. These methods were compared to directly counting of mites on leaves under a dissecting microscope. These methods were ethanol washing, a modified paraffin/ethanol meniscus technique, Tullgren funnel extraction and the Henderson and McBurnie mite brushing machine with consideration to: accuracy, precision and simplicity. In addition, two physically different leaf morphologies were compared; Prunus leaves which are glabrous with Malus leaves which are setaceous. Ethanol extraction consistently yielded the highest numbers of mites and was the most rapid method for recovering T. urticae from leaf samples, irrespective of leaf structure. In addition the samples could be processed and stored before final counting. The advantages and disadvantages of each method are discussed in detail.
Ditillo, J L; Kennedy, G G; Walgenbach, J F
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is an important pest of tomatoes in North Carolina. Resident populations of the predatory mite Phytoseiulus persimilis have recently been detected on field-grown tomatoes in central North Carolina, and potentially can be a useful biological control agent against T. urticae Laboratory bioassays were used to assess lethal and reproductive effects of 10 insecticides and five fungicides commonly used in commercial tomato production (chlorantraniliprole, spinetoram, permethrin, imidacloprid, dimethoate, dinotefuran, thiamethoxam, bifenthrin, fenpropathrin, lambda-cyhalothrin, azoxystrobin, chlorothalonil, boscalid, cyazofamid, and mancozeb) on P. persimilis adult females and eggs. Insecticides were tested using concentrations equivalent to 1×, 0.5×, and 0.1× of the recommended field rates. Fungicides were tested at the 1× rate only. Dimethoate strongly impacted P. persimilis with high adult mortality, reduced fecundity, and reduced hatch of eggs laid by treated adults, particularly at high concentrations. The pyrethroids lambda-cyhalothrin, bifenthrin, and fenpropathrin were associated with repellency and reproductive effects at high concentrations. Bifenthrin additionally caused increased mortality at high concentrations. Chlorantraniliprole, dinotefuran, and permethrin did not significantly affect mortality or reproduction. Imidacloprid significantly reduced fecundity and egg viability, but was not lethal to adult P. persimilis Thiamethoxam negatively impacted fecundity at the 1× rate. There were no negative effects associated with fungicide exposure with the exception of mancozeb, which impacted fecundity. Field trials were conducted to explore the in vivo impacts of screened insecticides on P. persimilis populations in the field. Field trials supported the incompatibility of dimethoate with P. persimilis populations. © The Authors 2016. Published by Oxford University Press on behalf
The Tuckerellidae is the only a phytophagous family within the Tetranychoidea (Acari) that retains the ancestral prostigmatan condition of three nymphal stages during development; however it is only the female developmental sequence that retains a tritonymphal stage. Adult females develop from a tr...
Because of their small size and tolerance to many of the control procedures used for a wide variety of commodities, Acari species have become one of the fastest, unwanted pest travelers since the beginning of this century. This special issue includes eleven studies on adventive and invasive Acari sp...
There are approximately 55,000 described Acari species, accounting for almost half of all known Arachnida species, but total estimated Acari diversity is reckoned to be far greater. One important source of currently hidden Acari diversity is cryptic speciation, which poses challenges to taxonomists ...
Zhang, Yan-Nan; Jiang, Jue-Ying-Qi; Zhang, Yi-Jing; Qiu, Ye; Zhang, Jian-Ping
Knowledge about the prey preference of polyphagous predators is important for determining their ability to suppress pest insects. Tetranychus truncatus (Tetranychidae), Tetranychus turkestani (Tetranychidae), and Thrips tabaci (Thripidae) often coexist in crops. Neoseiulus bicaudus (Wainstein) is a native predatory mite that was recently observed in the Xinjiang Uygur Autonomous Region of northwest China. The objective of this study was to assess the potential of N. bicaudus as a bio-control agent against the three pest species mentioned above. The results showed that N. bicaudus protonymphs, deutonymphs, and adults can be effective biological control agents for the three pest species. Neoseiulus bicaudus at all three developmental stages exhibited a Holling's Type II (convex) functional response to the prey. Neoseiulus bicaudus exhibited no preference between T. truncatus adults and T. turkestani adults, irrespective of the prey ratio. In comparison, N. bicaudus clearly preferred first-instar T. tabaci larvae to T. turkestani adults. The results of this study suggest that N. bicaudus could help control T. truncatus, T. turkestani, and T. tabaci. Among these pests, N. bicaudus may be most effective for first-instar T. tabaci. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Ghazy, Noureldin Abuelfadl; Amano, Hiroshi
This study investigated the feasibility of using the cannibalistic habits of the mite Neoseiulus californicus (McGregor) and controlling the relative humidity (RH) to prolong the survival time during the storage or shipment of this predatory mite. Three-day-old mated and unmated females were individually kept at 25 ± 1 °C in polypropylene vials (1.5 mL), each containing one of the following items or combinations of items: a kidney bean leaf disk (L), N. californicus eggs (E), and both a leaf disk and the eggs (LE). Because the leaf disk increased the RH in the vials, the RH was 95 ± 2 % under the L and LE treatments and 56 ± 6 % under the E treatment. The median lethal time (LT50) exceeded 50 days for the mated and unmated females under the LE treatment. However, it did not exceed 11 or 3 days for all females under the L or E treatments, respectively. Under the LE treatment, the mated and unmated females showed cannibalistic behavior and consumed an average of 5.2 and 4.6 eggs/female/10 days. Some of the females that survived for LT50 under each treatment were transferred and fed normally with a constant supply of Tetranychus urticae Koch. Unmated females were provided with adult males for 24 h for mating. Only females previously kept at LE treatment produced numbers of eggs equivalent to the control females (no treatment is applied). The results suggested that a supply of predator eggs and leaf material might have furnished nutrition and water vapor, respectively, and that this combination prolonged the survival time of N. californicus during storage. Moreover, this approach poses no risk of pest contamination in commercial products.
Apple pollen as a supplemental food source for the control of western flower thrips by two predatory mites, Amblyseius swirskii and Neoseiulus cucumeris (Acari: Phytoseiidae), on potted chrysanthemum.
Delisle, J F; Shipp, L; Brodeur, J
It has been shown that pollen as a dietary supplement may increase the establishment (development and reproduction) and survival of phytoseiid predatory mites, and therefore the pest control these mites can provide. In this study, the role of apple pollen as a supplemental food source was assessed as a means to increase the efficiency of two predatory mite species, Neoseiulus cucumeris and Amblyseius swirskii, for control of western flower thrips, Frankliniella occidentalis, under greenhouse conditions. The impact of apple pollen on thrips populations and predator establishment on a greenhouse chrysanthemum crop was determined over a 4-week period. The two mite species were released separately and in combination with and without pollen with two control treatments (thrips only and thrips + pollen). The introduction of A. swirskii together with pollen application provided the best control of thrips (adults and immatures). The establishment of N. cucumeris was very low in the crop during the greenhouse trial. This could be attributable, in part, to their response to extreme temperature ranges that were encountered during the greenhouse cage trials. The use of A. swirskii alone and the mixed population of the two predatory mite species without pollen resulted in the lowest frequencies of plants with heavy damage, followed by the same treatments with the addition of apple pollen.
Chen, Wei; Li, Dunsong; Zhang, Min; Zhao, Yunlong; Wu, Wenjing; Zhang, Guren
In order to explore the role of heat shock proteins (Hsps) during thermal stress and development in the predatory mite Neoseiulus cucumeris (Oudemans), we cloned and characterized five full-length Hsp genes. We investigated the expression levels of these genes by quantitative real-time PCR. The five genes characterized here were NcHsp90, NcHsp75, NcHsp70, NcHsp60, and NcHsp40. These Hsps showed high sequence conservation and had greatest identity with heat shock proteins of Metaseiulus occidentalis and other mite and insect species. All five NcHsp genes showed changes in their levels of expression during development. Higher levels of expression were observed in adult females than in adult males, but there were no significant changes between pre-oviposition and post-oviposition stages in the females. NcHsp90, NcHsp75, and NcHsp70 expression levels were up-regulated after a heat shock, and the increases in NcHsp75 and NcHsp70 expression levels were maintained for at least 3 h. Up-regulation of NcHsp60 and NcHsp40 was not detected after 1 h at a high temperature (35-45 °C); however, a significant down-regulation was observed after 3 h heat exposure at 35 °C and 3 h recovery at 25 °C. Cold shock treatment (-5 to 15 °C) for 1 h did not acute elicit changes in the expression levels of any of the genes. At 5 °C, the expression levels of NcHsp90 significantly increased after 6 or 24 h exposure compared to the levels after 1 h exposure. Thus, expression of Hsp genes in N. cucumeris reflected developmental changes, sexual difference, and variable induced response to thermal stress. Increased expression of Hsps might protect N. cucumeris individuals under extreme temperature conditions. Therefore, it may be possible to enhance the thermal tolerance of commercially available N. cucumeris using temperature acclimation. Treatment at 35 °C should be suitable for such acclimation.
Auger, Philippe; Kreiter, Serge; Mattioda, Helene; Duriatti, Andrea
The side effects of mancozeb on the predatory mite Typhlodromus pyri were studied in 4-year field trials on grapevine and in the laboratory. In the field, the effect of mancozeb varied according to previous mancozeb use. In vineyards where mancozeb had commonly been used over years, this fungicide is generally slightly toxic, in some cases moderately toxic and rarely toxic. In plots were mancozeb has never been used, its effect on T. pyri was more pronounced and varied from moderately toxic to toxic. Despite the toxicity of mancozeb, T. pyri populations have never been eradicated. Laboratory results obtained with the French CEB guideline no. 167 confirmed those of the 4-year field study: mancozeb was significantly more toxic to T. pyri populations collected in plots where it had rarely been used before the field experiment. In plots where mancozeb had been used for a long time, the susceptibility of T. pyri populations to this fungicide was reduced and female survival, fecundity but also viability of female progeny were less affected by mancozeb. Even though toxicity of mancozeb increased in controlled conditions, a significant correlation was established between field and laboratory results.
Tsolakis, Haralabos; Principato, Dennj; Jordà Palomero, Raoul; Lombardo, Alberto
Typhlodromus laurentii and Iphiseius degenerans are two generalist phytoseiid mites, broadly spread in the Mediterranean area, especially in citrus orchards. In the present work we report results on various biological and life table parameters of the two phytoseiids, fed on pollen of Oxalis pes-caprae and various stages of the tetranychid Panonychus citri. Iphiseius degenerans had the shortest post embryonic development (6.53 days), the highest oviposition rate (1.83 eggs/female/day) and the shortest mean time between eggs laid (0.55 day) on Oxalis pollen, whereas the two food types did not influence these parameters in T. laurentii. However, Oxalis pollen showed a positive effect on the survivorship of the latter phytoseiid, with a median life time (LT50) of 44.51 days, which was two times longer than that registered on prey with the same phytoseiid, and on both food types with I. degenerans. This latter species had a better performance on the pollen (rm = 0.243, λ = 1.275, Ro = 22.88, DT = 2.85) than on prey (rm = 0.182, λ = 1.199, Ro = 17.43, DT = 3.81). On the other hand, the pollen influenced the net reproductive rate (25.43 females/female) of T. laurentii positively but showed the same effect as the prey on the other demographic parameters. Our results improve knowledge on the feeding behaviour of the above mentioned phytoseiids on two food sources that could represent the main possibility to maintain a consistent population of these predators during winter. Moreover, both phytoseiids were shown to be good biocontrol candidates of P. citri populations.
Reducing the impact of pesticides on biological control in Australian vineyards: pesticide mortality and fecundity effects on an indicator species, the predatory mite Euseius victoriensis (Acari: Phytoseiidae).
Bernard, Martina B; Cole, Peter; Kobelt, Amanda; Horne, Paul A; Altmann, James; Wratten, Stephen D; Yen, Alan L
Laboratory bioassays on detached soybean, Glycine max (L.) Merr., leaves were used to test 23 fungicides, five insecticides, two acaricides, one herbicide, and two adjuvants on a key Australian predatory mite species Euseius victoriensis (Womersley) in "worst-case scenario" direct overspray assays. Zero- to 48-h-old juveniles, their initial food, and water supply were sprayed to runoff with a Potter tower; spinosad and wettable sulfur residues also were tested. Tests were standardized to deliver a pesticide dose comparable with commercial application of highest label rates at 1,000 liter/ha. Cumulative mortality was assessed 48 h, 4 d, and 7 d after spraying. Fecundity was assessed for 7 d from start of oviposition. No significant mortality or fecundity effects were detected for the following compounds at single-use application at 1,000 liter/ha: azoxystrobin, Bacillus thuringiensis (Bt) subsp. kurstaki, captan, chlorothalonil, copper hydroxide, fenarimol, glyphosate, hexaconazole, indoxacarb, metalaxyl/copper hydroxide, myclobutanil, nonyl phenol ethylene oxide, phosphorous acid, potassium bicarbonate, pyraclostrobin, quinoxyfen, spiroxamine, synthetic latex, tebufenozide, triadimenol, and trifloxystrobin. Iprodione and penconazole had some detrimental effect on fecundity. Canola oil as acaricide (2 liter/100 liter) and wettable sulfur (200 g/100 liter) had some detrimental effect on survival and fecundity and cyprodinil/fludioxonil on survivor. The following compounds were highly toxic (high 48-h mortality): benomyl, carbendazim, emamectin benzoate, mancozeb, spinosad (direct overspray and residue), wettable sulfur (> or = 400 g/100 liter), and pyrimethanil; pyrimethanil had no significant effect on fecundity of surviving females. Indoxacarb safety to E. victoriensis contrasts with its toxicity to key parasitoids and chrysopid predators. Potential impact of findings is discussed.
Stathakis, Theodoros I; Kapaxidi, Eleftheria V; Papadoulis, Georgios Th
Two new species, Neoseiulus elisiensis n. sp. and Neoseiulus neomarginatus n. sp., are described from Greece. Neoseiulus leucophaeus (Athias-Henriot) is re-described and illustrated based on specimens collected on Thymelaea hirsuta (L.) Endl. A key to all species of the genus Neoseiulus Hughes reported from Greece is provided.
Jiménez, Sofía; McMurtry, James A; De Moraes, Gilberto J
Neoparaphytoseius charapa n. sp. is described, based on the morphology of adult females and males collected on Inga edulis (Mart.) (Fabaceae) in northeastern Peru. Neoparaphytoseius Chant & McMurtry is redefined on the basis of the new species and re-examination of its type species N. sooretamus Chant & McMurtry.
Zanardi, Odimar Zanuzo; Bordini, Gabriela Pavan; Franco, Aline Aparecida; de Morais, Matheus Rovere; Yamamoto, Pedro Takao
The species and varieties of citrus plants that are currently grown can favor the population growth of the citrus red mite Panonychus citri (McGregor) (Prostigmata: Tetranychidae) and alter the pest management programs in citrus groves. In this study we evaluated, in the laboratory, the development and reproduction of P. citri and estimated its life table parameters when reared on four varieties of Citrus sinensis (L.) Osbeck (Valencia, Pera, Natal, and Hamlin), one variety of Citrus reticulata Blanco (Ponkan) and one variety of Citrus limon (L.) Burm. (Sicilian). The incubation period and egg viability were not affected by the host plant. However, the development and survival of the immature stage were significantly lower on Hamlin orange than on Valencia, Pera and Natal oranges, Ponkan mandarin and Sicilian lemon. The fecundity and oviposition period of females were lower on Hamlin orange than on the other hosts. Mites reared on Valencia orange and Sicilian lemon had a higher net reproductive rate (R 0 ), intrinsic growth rate (r) and finite rate of increase (λ), and a shorter interval between generations (T) than on Pera, Natal and Hamlin oranges and Ponkan mandarin. On the other hand, mites reared on Hamlin orange had the lowest R 0 , r and λ and the highest T among the hosts. Based on the results obtained we recommend that for Valencia orange and Sicilian lemon, the mite monitoring programs should be more intense to detect the initial infestation of pest, avoiding the damage in plants and the increase in production costs.
Van Leeuwen, Thomas; Stillatus, Vincent; Tirry, Luc
A laboratory susceptible strain of Tetranychus urticae was selected with chlorfenapyr resulting in a resistant strain. After 12 cycles of exposure, the resistance ratio (RR) calculated from the LC50s of susceptible and selected strain was 580. The resistant strain was screened with 16 currently used acaricides for cross-resistance. Cross-resistance was detected with amitraz (RR = 19.1), bifenthrin (RR = 1.3), bromopropylate (RR = 7.5), clofentezine (RR = 29.6) and dimethoate (RR = 17.6). No cross-resistance was detected with the new molecules acequinocyl, bifenazate and spirodiclofen. Mortality caused by chlorfenapyr in the F1 progeny from reciprocal crosses between both strains indicated that the mode of inheritance was incomplete recessive. Mortality in F2 progeny indicated that the resistance was under the control of more than one gene. Synergist experiments with S,S,S-tributylphosphorotrithioate (DEF), piperonylbutoxide (PBO) and diethylmaleate (DEM), which are inhibitors of esterases, monooxygenases and glutathion-S-transferases respectively, suggested a major role of esterases in the resistance to chlorfenapyr.
Li, Dongmei; Fan, Qing-Hai; Waite, David W; Gunawardana, Disna; George, Sherly; Kumarasinghe, Lalith
Spider mites of the genus Tetranychus are difficult to identify due to their limited diagnostic characters. Many of them are morphologically similar and males are needed for species-level identification. Tetranychus urticae is a common interception and non-regulated pest at New Zealand's borders, however, most of the intercepted specimens are females and the identification was left at Tetranychus sp. Consequently, the shipments need to be fumigated. DNA sequencing and PCR-restriction fragment length polymorphism (PCR-RFLP) protocols could be used to facilitate the accurate identification. However, in the context of border security practiced in New Zealand, insect identifications are required to be provided within four hours of receiving the samples; thus, those molecular methods are not sufficient to meet this requirement. Therefore, a real-time PCR TaqMan assay was developed for identification of T. urticae by amplification of a 142 bp Internal Transcribed Spacer (ITS) 1 sequence. The developed assay is rapid, detects all life stages of T. urticae within three hours, and does not react with closely related species. Plasmid DNA containing ITS1 sequence of T. uritcae was serially diluted and used as standards in the real-time PCR assay. The quantification cycle (Cq) value of the assay depicted a strong linear relationship with T. urticae DNA content, with a regression coefficient of 0.99 and efficiency of 98%. The detection limit was estimated to be ten copies of the T. urticae target region. The assay was validated against a range of T. urticae specimens from various countries and hosts in a blind panel test. Therefore the application of the assay at New Zealand will reduce the unnecessary fumigation and be beneficial to both the importers and exporters. It is expected that the implementation of this real-time PCR assay would have wide applications in diagnostic and research agencies worldwide.
Li, Dongmei; Fan, Qing-Hai; Waite, David W.; Gunawardana, Disna; George, Sherly; Kumarasinghe, Lalith
Spider mites of the genus Tetranychus are difficult to identify due to their limited diagnostic characters. Many of them are morphologically similar and males are needed for species-level identification. Tetranychus urticae is a common interception and non-regulated pest at New Zealand’s borders, however, most of the intercepted specimens are females and the identification was left at Tetranychus sp. Consequently, the shipments need to be fumigated. DNA sequencing and PCR-restriction fragment length polymorphism (PCR-RFLP) protocols could be used to facilitate the accurate identification. However, in the context of border security practiced in New Zealand, insect identifications are required to be provided within four hours of receiving the samples; thus, those molecular methods are not sufficient to meet this requirement. Therefore, a real-time PCR TaqMan assay was developed for identification of T. urticae by amplification of a 142 bp Internal Transcribed Spacer (ITS) 1 sequence. The developed assay is rapid, detects all life stages of T. urticae within three hours, and does not react with closely related species. Plasmid DNA containing ITS1 sequence of T. uritcae was serially diluted and used as standards in the real-time PCR assay. The quantification cycle (Cq) value of the assay depicted a strong linear relationship with T. urticae DNA content, with a regression coefficient of 0.99 and efficiency of 98%. The detection limit was estimated to be ten copies of the T. urticae target region. The assay was validated against a range of T. urticae specimens from various countries and hosts in a blind panel test. Therefore the application of the assay at New Zealand will reduce the unnecessary fumigation and be beneficial to both the importers and exporters. It is expected that the implementation of this real-time PCR assay would have wide applications in diagnostic and research agencies worldwide. PMID:26147599
Tetranychus kanzawai Kishida and Panonychus citri (McGregor) are two major acarine pests of the principal papaya variety in Taiwan, and they often co-occur in the same papaya screenhouses. This study measured prey acceptability, foraging schedule, short-term consumption rate, and handling time of la...
Low temperature–scanning electron microscopy to evaluate morphology and predation of Scolothrips sexmaculatus Pergande (Thysanoptera: Thripidae) against spider mites (Acari: Tetranychidae: Tetranychus species)
This paper evaluates the potential usefulness of low temperature-scanning electron microscopy (LT-SEM) to evaluate morphology and predation behavior of the six-spotted thrips (Scolothrips sexmaculatus Pergande) against the two-spotted spider mite (Tetranychus urticae (Koch)). Morphological features...
Gene flow and spatio-temporal genetic variation among sympatric populations of Tetranychus kanzawai (Acari: Tetranychidae) occurring on different host plants, as estimated by microsatellite gene diversity.
Nishimura, Shinya; Hinomoto, Norihide; Takafuji, Akio
We investigated spatio-temporal genetic variation in allele frequency and estimated gene flow among sympatric populations of Tetranychus kanzawai on different host plants by the use of microsatellite markers. In the analysis of spatial genetic variation, no isolation by distance was detected among the populations. Gene flow between populations on Hydrangea macrophylla and those on other host plants was relatively restricted, whereas the populations on Akebia quinata and Clerodendrum trichotomum were almost panmictic. Our study on temporal genetic variation showed (1) that population differentiation was slightly reduced during the period from April to May owing to frequent gene flow among populations; and (2) that population differentiation was greatly enhanced from May to October because of bottleneck effects. Genetic differentiation among T. kanzawai populations was caused by the effect of host plants rather than by the effect of geographic distance among populations, suggesting possibility of sympatric host race formation in this species.
Navajas, M; Gutierrez, J; Bonato, O; Bolland, H R; Mapangou-Divassa, S
Intraspecific diversity in Cassava Green Mite Mononychellus progresivus Doreste was examined using individuals collected in Benin and the Congo and in Columbia and Brazil. Comparisons were based on mitochondrial and ribosomal DNA sequences and the results of several cross-breeding experiments. Sequence variation was examined in a total of 1139 base pairs (bp) constituting the ITS2 ribosomal DNA (805 bp) and a fragment of the Cytochrome Oxidase I (COI) gene (334 bp). Sequence divergence is low, ranging from 0% to 2.1% for COI and from 0% to 0.4% for ITS2. Inter-strain comparisons have shown that the two African populations appear to be identical. They were similar to the Colombian population while the Brazilian population was clearly different. The data support the hypothesis of a single introduction of the species in the two African populations. Crossing experiments have shown partial hybrid sterility, suggesting a genetic incompatibility consistent with differences detected by sequence data. The results show the usefulness of molecular markers as a tool for determining taxonomic status and dispersion paths in spider mites.
Elliot, S L; de Moraes, G J; Delalibera, I; da Silva, C A; Tamai, M A; Mumford, J D
The cassava green mite, Mononychellus tanajoa (Bondar), is an exotic pest in Africa and is the target of a classical biological control programme. Field data from the Neotropics, where it is indigenous, are presented for the first time, charting the variation in abundance of M. tanajoa over several seasons. This was highly variable, with a characteristic trough mid-year and a peak at the turn of the year. This pattern corresponded positively with rainfall levels, appearing to fit a phenology also characteristic of African studies, where rainfall at the start of the wet season promotes a leaf flush and so growth in M. tanajoa populations. Analyses implied some impact of leaf-inhabiting predatory mites (predominantly Neoseiulus idaeus Denmark & Muma) and a considerable impact of the fungal pathogen Neozygites floridana Fisher on M. tanajoa populations. This pathogen was not observed in the host population for several (generally dry) periods implying survival outside the host, perhaps as resting spores. This is a particularly desirable characteristic of a biological control agent. It is therefore proposed that N. floridana might be of particular use in drier cassava-growing areas where rainfall at the outset of the wet season is not sufficiently intense to cause heavy M. tanajoa mortality but may be sufficient to stimulate epizootics of the fungal pathogen, protecting the flush of new cassava growth.
González-Zamora, J E; López, C; Avilla, C
Eutetranychus orientalis has become an important pest of the ornamental tree Melia azedarach in the city of Seville (Spain). Trees suffer total defoliation at the end of summer. Studies were conducted in a regular plantation of this tree in the Miraflores Park in 2008 and 2009, to determine the arthropod faunal composition, with particular interest in the possible natural enemies of E. orientalis. Eutetranychus orientalis accounted for 98.3% of the arthropods found on the leaflets. Two species of phytoseiids were found, Euseius scutalis and Euseius stipulatus, but they only represented 0.2% of the arthropods. The most abundant insect was the predator thrips Scolothrips longicornis, which accounted for 0.9% of the arthropods found. The population of E. orientalis reached two peaks in 2008, with 325 individuals per leaflet in August, and 100 individuals per leaflet in November. Scolothrips longicornis densities closely followed E. orientalis, and predation was observed on various mite instars. Phytoseiids did not show such a response to the E. orientalis densities. Eutetranychus orientalis was more abundant in the exterior part of the plantation. No differences of arthropod densities were found between the various orientations in the plantation (north vs. south, east vs. west), although E. orientalis densities were different between rows. Distribution of E. orientalis population was highly aggregative, that of S. longicornis population was less aggregative, whereas the phytoseiid population showed a random distribution.
Miresmailli, Saber; Bradbury, Rod; Isman, Murray B
Bioassays of Rosmarinus officinalis L. essential oil and blends of its major constituents were conducted using host-specific strains of the two-spotted spider mite, Tetranychus urticae Koch, on bean and tomato plants. Two constituents tested individually against a bean host strain and five constituents tested individually against a tomato host strain accounted for most of the toxicity of the natural oil. Other constituents were relatively inactive when tested individually. Toxicity of blends of selected constituents indicated a synergistic effect among the active and inactive constituents, with the presence of all constituents necessary to equal the toxicity of the natural oil. Copyright (c) 2006 Society of Chemical Industry.
Xia, Wen-Kai; Ding, Tian-Bo; Niu, Jin-Zhi; Liao, Chong-Yu; Zhong, Rui; Yang, Wen-Jia; Liu, Bin; Dou, Wei; Wang, Jin-Jun
Chitin synthase synthesizes chitin, which is critical for the arthropod exoskeleton. In this study, we cloned the cDNA sequences of a chitin synthase 1 gene, PcCHS1, in the citrus red mite, Panonychus citri (McGregor), which is one of the most economically important pests of citrus worldwide. The full-length cDNA of PcCHS1 contains an open reading frame of 4605 bp of nucleotides, which encodes a protein of 1535 amino acid residues with a predicted molecular mass of 175.0 kDa. A phylogenetic analysis showed that PcCHS1 was most closely related to CHS1 from Tetranychus urticae. During P. citri development, PcCHS1 was constantly expressed in all stages but highly expressed in the egg stage (114.8-fold higher than in the adult). When larvae were exposed to diflubenzuron (DFB) for 6 h, the mite had a significantly high mortality rate, and the mRNA expression levels of PcCHS1 were significantly enhanced. These results indicate a promising use of DFB to control P. citri, by possibly acting as an inhibitor in chitin synthesis as indicated by the up-regulation of PcCHS1 after exposure to DFB. PMID:24590130
Örtücü, Serkan; Algur, Ömer Faruk
This study was conducted to isolation entomopathogenic fungi for possible use in biocontrol of two-spotted spider mite Tetranychus urticae Koch. and to determine their pathogenicity. For this purpose, plant leaves infected with T. urticae were collected from Erzurum, Kars and Ardahan. At laboratory, the internal and external mycoflora of T.urticae individuals on plant leaves were determined. As a result of isolation, twenty-five different fungi species belonging to the genera Acremonium, Alternaria, Aspergillus, Beauveria, Cladosporium, Gliocladium, Humicola, Penicillium, Trichoderma, Isaria, Ulocladium and Verticillium were obtained. Pathogenicity of this forty-five isolate belonging to twenty-five species were evaluated. As a test organism, T. urticae was used and suspensions (1 × 108conidia ml-1) were prepared in Tween 80. 2ml suspension of a single dose was sprayed onto down side of bean leaf discs using hand sprayer. Mortality was recorded daily for 7 days. A total of twelve isolates belonging to three species were determined to be pathogen against T.urticae. According to scale used: AT020 Isaria farinosa and AT025 Cladosporium cladosporioides were determined as least pathogen, AT037 and AT101 Beauveria bassiana, and AT019 and AT026 C. cladosporioides, and AT035 and AT036 I. farinosa as moderate pathogen, AT007, AT021, AT034 and AT076 B. bassiana as highly pathogen. The other thirty-three isolates found that not pathogenic against T.urticae.
Osperalycus tenerphagus, a new genus and species of Nematalycidae (Acari: Endeostigmata), is described from Ohio, USA, using light microscopy and low temperature scanning electron microscopy. Specimens were extracted from two different loam soils. This genus can be readily distinguished from the oth...
Ermilov, Sergey G.
Abstract A species list of identified oribatid mite taxa (Acari, Oribatida) in the fauna of Vietnam is provided. During 1967–2015, a total of 535 species/subspecies from 222 genera and 81 families was registered. Of these, 194 species/subspecies were described as new for science from Vietnam. PMID:26798306
Rezende, D D M; Fadini, M A M; Oliveira, H G; Oliveira, C M; Melo, J W S; Guedes, R N C; Pallini, A
Phytoseiulus macropilis Banks (Acari: Phytoseiidae) is an effective predator of tetranychid mites, but there are no data on its response to pesticides. We investigated the resistance of the predatory mite P. macropilis to the acaricides abamectin and dimethoate, and we examined the fitness costs associated with resistance. Two populations were tested: one from conventional cultivation and another from an area not commercially exploited. After the application of acaricides to the predator, we determined the lethal effects of the acaricides, the instantaneous rate of population increase (r(i)), the predation on Tetranychus urticae Koch (Acari: Tetranychidae) and its ability to locate prey in an olfactometer. P. macropilis exhibited resistance to dimethoate only. The low level of resistance (9.4x) of the predator did not affect their ability to locate prey. However, the dimethoate resistant population was not as effective in contatining prey population when in lower density and exhibited a more pronounced decrease of r(i) in the presence of this acaricide, due to the reduced oviposition of the predator, a likely consequence of the different genetic background of this population.
Xiao, Yingfang; Osborne, Lance S.; Chen, Jianjun; McKenzie, Cindy L.
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is an important pest of vegetables and other economically important crops. This study evaluated the functional responses and prey-stage preferences of three species of predators, a predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Cecidomyiidae), and two predatory mite species, Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) and Amblyseius swirskii (AnthiasHenriot), with T. urticae as the host, under laboratory conditions. The results showed that F. acarisuga was highly effective and the two species of predacious mites were moderately effective in feeding on T. urticae eggs. Logistic regression analysis suggested Type II (convex) functional responses for all three species. However, based on the estimates of the handling time and the attacking rates, the three predators had different predation capacities. Among the three species, F. acarisuga had the highest predation on T. urticae. The maximum daily predation by a larval F. acarisuga was 50 eggs/day, followed by a female N. californicus (25.6 eggs/day) and a female A. swirskii (15.1 eggs/day). A female N. californicus produced more eggs than a female A. swirskii did when they both fed on T. urticae eggs. In addition, all three predator species had no preystage preference for either prey eggs or nymphs. The findings from this study could help select better biological control agents for effective control of T. urticae and other pests in vegetable productions. PMID:23879370
Todokoro, Yasuhiro; Higaki, Tomomi
The predatory mite Neoseiulus womersleyi (Schicha) (Acari: Phytoseiidae) is an important natural enemy of the Kanzawa spider mite, Tetranychus kanzawaki Kishida (Acari: Tetranychidae), in tea fields. Attraction and preservation of natural enemies by habitat management to reduce the need for acaricide sprays is thought to enhance the activity of N. womersleyi. To better conserve N. womersleyi in the field, however, it is essential to elucidate the population genetic structure of this species. To this end, we developed ten microsatellite DNA markers for N. womersleyi. We then evaluated population structure of N. womersleyi collected from a tea field, where Mexican sunflower, Tithonia rotundifolia (Mill.), was planted to preserve N. womersleyi. Seventy-seven adult females were collected from four sites within 200 m. The fixation indexes FST among subpopulations were not significantly different. The kinship coefficients between individuals did not differ significantly within a site as a function of the sampling dates, but the coefficients gradually decreased with increasing distance. Bayesian clustering analysis revealed that the population consisted of three genetic clusters, and that subpopulations within 100 m, including those collected on T. rotundifolia, were genetically similar to each other. Given the previously observed population dynamics of N. womersleyi, it appears that the area inhabited by a given cluster of the mite did not exceed 100 m. The estimation of population structure using microsatellite markers will provide valuable information in conservation biological control. PMID:20625919
Vangansbeke, Dominiek; Audenaert, Joachim; Nguyen, Duc Tung; Verhoeven, Ruth; Gobin, Bruno; Tirry, Luc; De Clercq, Patrick
The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen's inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C) on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae) and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen's inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes.
Vangansbeke, Dominiek; Audenaert, Joachim; Nguyen, Duc Tung; Verhoeven, Ruth; Gobin, Bruno; Tirry, Luc; De Clercq, Patrick
The impact of daily temperature variations on arthropod life history remains woefully understudied compared to the large body of research that has been carried out on the effects of constant temperatures. However, diurnal varying temperature regimes more commonly represent the environment in which most organisms thrive. Such varying temperature regimes have been demonstrated to substantially affect development and reproduction of ectothermic organisms, generally in accordance with Jensen’s inequality. In the present study we evaluated the impact of temperature alternations at 4 amplitudes (DTR0, +5, +10 and +15°C) on the developmental rate of the predatory mites Phytoseiulus persimilis Athias-Henriot and Neoseiulus californicus McGregor (Acari: Phytoseiidae) and their natural prey, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). We have modelled their developmental rates as a function of temperature using both linear and nonlinear models. Diurnally alternating temperatures resulted in a faster development in the lower temperature range as compared to their corresponding mean constant temperatures, whereas the opposite was observed in the higher temperature range. Our results indicate that Jensen’s inequality does not suffice to fully explain the differences in developmental rates at constant and alternating temperatures, suggesting additional physiological responses play a role. It is concluded that diurnal temperature range should not be ignored and should be incorporated in predictive models on the phenology of arthropod pests and their natural enemies and their performance in biological control programmes. PMID:25874697
Otsuki, Hatsune; Yano, Shuichi
Predators can affect prey dispersal lethally by direct consumption or non-lethally by making prey hesitate to disperse. These lethal and non-lethal effects are detectable only in systems where prey can disperse between multiple patches. However, most studies have drawn their conclusions concerning the ability of predatory mites to suppress spider mites based on observations of their interactions on a single patch or on heavily infested host plants where spider mites could hardly disperse toward intact patches. In these systems, specialist predatory mites that penetrate protective webs produced by spider mites quickly suppress the spider mites, whereas generalist predators that cannot penetrate the webs were ineffective. By using a connected patch system, we revealed that a generalist ant, Pristomyrmex punctatus Mayr (Hymenoptera: Formicidae), effectively prevented dispersal of spider mites, Tetranychus kanzawai Kishida (Acari: Tetranychidae), by directly consuming dispersing individuals. We also revealed that a generalist predatory mite, Euseius sojaensis Ehara (Acari: Phytoseiidae), prevented between-patch dispersal of T. kanzawai by making them hesitate to disperse. In contrast, a specialist phytoseiid predatory mite, Neoseiulus womersleyi Schicha, allowed spider mites to escape an initial patch, increasing the number of colonized patches within the system. Our results suggest that ants and generalist predatory mites can effectively suppress Tetranychus species under some conditions, and should receive more attention as agents for conservation biological control in agroecosystems.
Aguirre, D H; Gaido, A B; Cafrune, M M; Guglielmone, A A; Estrada-Peña, A
Attacks by adult stages of the soft tick Argas (Argas) neghmei (Acari: Argasidae) on inhabitants of the High Andean plateau of Argentina are reported. This is the first local report of this species, which was previously found in the north of Chile. Taxonomic differences between A. (A.) neghmei and other neotropical and exotic species of the genus are underlined. The status of the knowledge about the Argentine argasid fauna is briefly described.
Lynell K. Tanigoshi
Acari of the family Phytoseiidae are important predators of spider mites. Since the taxonomic treatises of Nesbitt (1951) and later by Chant (1959), over 1000 described taxa have been listed by Moraes et al. (1986).
Mangalaus ikrishianusandhanus n. gen., n. sp., (Acari: Prostigmata: Eriophyoidea), collected from erineum on the underside of leaves of Cordia dichotoma (Boraginaceae) is described and illustrated from specimens collected at the Indian Agricultural Research Institute (IARI) in New Delhi, India....
Klimovičová, Miroslava; Mikula, Peter; Kahure, Njoki; Hromada, Martin
Two new species of quill mites (Acari: Prostigmata: Syringophilidae) collected from passeriform and coraciiform birds from Kenya are described : Neoaulonastus apalis sp. nov. from Apalis porphyrolaema Reichenow and Neumann (Passeriformes: Cisticolidae) and Peristerophila upupi sp. nov. from Upupa epops Linnaeus (Coraciiformes: Upupidae). Additionally, 3 new host species: Cisticola hunteri Shelley, 1889; Acrocephalus baeticatus (Vieillot, 1817) and Ploceus xanthops (Hartlaub, 1862) from Kenya and two new localities are recorded for genera: Aulobia Kethley, 1970; Neoaulonastus Skoracki, 2004 and Syringophiloidus Kethley, 1970. The previous and the latest knowledge about syringophilid mites from Kenya is summarized in tabular form.
González-Domínguez, S G; Santillán-Galicia, M T; González-Hernández, V; Suárez Espinosa, J; González-Hernández, H
The strawberry, Fragaria×ananassa Duchesne (Rosales: Rosaceae), is an important crop in Mexico. We evaluated the tolerance of three newly developed Mexican strawberry varieties (CP0615, CPLE-7, and CPJacona) to Tetranychus urticae Koch (Trombidiformes: Tetranychidae), the most important pest of strawberry. We evaluated the effect of three different initial mite densities on population growth, duration of each developmental stage and survival of T. urticae on the three strawberry varieties. We also compared the photosynthetic activity (Pn), sub-stomatal CO2 concentration (Ci), stomatal conductance (gs) and the area of leaf damaged in the three varieties. The largest final density of mites occurred on the variety CP0615, followed by the varieties CPLE-7 and CPJacona. There were no significant differences in the duration of T. urticae developmental stages amongst the varieties, except for larvae where the shortest duration was on variety CPLE-7. The proportion of eggs reaching the adult stage (survival) was significantly lower on the variety CPLE-7. The number and morphology of the trichomes did not play an important role in the outcomes, as they were similar in the three varieties. There were no significant differences in Pn, Ci, and gs values amongst the three varieties in the presence and absence of T. urticae. The area of leaf damaged in variety CPLE-7 was significantly smaller than for the other varieties. Based on these results, and with regard to spider mite tolerance, we believe that the variety CPLE-7 has the greatest potential for further development, and eventually, for use on a commercial scale in Mexico.
Skelton, A C; Birkett, M A; Pickett, J A; Cameron, M M
Dermatophagoides farinae Hughes (Acari: Epidermoptidae), the American house dust mite, and Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), the mold mite, are medically and economically important but controlling them has proved difficult, and recolonization is commonplace. Their behavioral responses to different sources of volatile chemicals are still not fully elucidated. For the first time, the Y-tube olfactometer, which is an enclosed bioassay to resolve responses to test and control volatiles, has been successfully used with these mites. Mites were tested individually, and both T. putrescentiae and D. farinae responded to food volatiles. Y-tube olfactometers may be used to test for potential semiochemicals, thereby increasing knowledge of our behavior of astigmatic mites.
Khaustov, Alexander A
Twenty four species of pygmephoroid mites (Acari: Pygmephoroidea: Neopygmephoridae, Scutacaridae, Microdispidae) are recorded from the ant Lasius flavus (Fabricius) or from its nests from Western Siberia and Crimea. Four of them of the genus Scutacarus Gros, 1845 (Acari: Scutacaridae), S. insolitus sp. nov., S. heterotrichus sp. nov., S. moseri sp. nov. and S. sibiriensis sp. nov. are described as new for science. Four species of scutacarid mites are recorded for the first time in Russia. The comparison of pygmephoroid mite communities associated with Lasius flavus from Crimean and West Siberian populations and notes on phoresy of pygmephoroid mites on ants are provided.
Azevedo, Alexsander Araújo; Marcos Linardi, Pedro; Coutinho Zanatta, Maria Teresa
Ectoparasites were recovered from Brazilian bats captured from April to November 1997 at or near Parque Estadual do Rio Doce, State of Minas Gerais, southeastern Brazil. Sixty bats were collected, representing three families and 13 species. Five Acari families were recorded: Myobiidae, Trombiculidae, Labidocarpidae, Macronyssidae, and Spinturnicidae. The macronyssid Radfordiella desmodi Radovsky (71 specimens) and the spinturnicid Periglichrus iheringi Oudemans (45 specimens) were the most abundant mite species. They were mainly recorded on Desmodus rotundus (Geoffroy) and Artibeus litratus (Ofers), respectively. Among trombiculid chiggers, the genus Colicus Brennan (55 specimens) was predominant and found mainly on Carollia perspicillata (L.). The current study presents new data about host-parasite relationships and increases the understanding of geographical distribution for some mite and chigger species.
Gerson, Uri; Weintraub, Phyllis G
This review discusses the economically important pest mites (Acari) of greenhouses, aspects of their biology, and the acarine predators that attack them as well as various insect pests. Greenhouse factors affect pest mites as well as their natural enemy populations and their interactions. Conversely, pest mites affect greenhouse management in terms of the chemical and biological methods required to control their populations. Structure affects heating, cooling, and light, which can be manipulated with suitable screens. Crops often select for pests and their mite enemies. Both groups may be affected in greenhouses by adding pollen and by a CO(2)-enriched atmosphere. These factors impact pest mite populations, the damage they cause, and the methods used to control them. The possibility of incipient evolution occurring in greenhouses, along with the benefits and consequences for pest control, is discussed. Copyright © 2012 by Annual Reviews. All rights reserved.
Martinez, Manuel; Santamaria, Maria Estrella; Diaz-Mendoza, Mercedes; Arnaiz, Ana; Carrillo, Laura; Ortego, Felix; Diaz, Isabel
This review deals with phytocystatins, focussing on their potential role as defence proteins against phytophagous arthropods. Information about the evolutionary, molecular and biochemical features and inhibitory properties of phytocystatins are presented. Cystatin ability to inhibit heterologous cysteine protease activities is commented on as well as some approaches of tailoring cystatin specificity to enhance their defence function towards pests. A general landscape on the digestive proteases of phytophagous insects and acari and the remarkable plasticity of their digestive physiology after feeding on cystatins are highlighted. Biotechnological approaches to produce recombinant cystatins to be added to artificial diets or to be sprayed as insecticide-acaricide compounds and the of use cystatins as transgenes are discussed. Multiple examples and applications are included to end with some conclusions and future perspectives.
Martinez, Manuel; Santamaria, Maria Estrella; Diaz-Mendoza, Mercedes; Arnaiz, Ana; Carrillo, Laura; Ortego, Felix; Diaz, Isabel
This review deals with phytocystatins, focussing on their potential role as defence proteins against phytophagous arthropods. Information about the evolutionary, molecular and biochemical features and inhibitory properties of phytocystatins are presented. Cystatin ability to inhibit heterologous cysteine protease activities is commented on as well as some approaches of tailoring cystatin specificity to enhance their defence function towards pests. A general landscape on the digestive proteases of phytophagous insects and acari and the remarkable plasticity of their digestive physiology after feeding on cystatins are highlighted. Biotechnological approaches to produce recombinant cystatins to be added to artificial diets or to be sprayed as insecticide–acaricide compounds and the of use cystatins as transgenes are discussed. Multiple examples and applications are included to end with some conclusions and future perspectives. PMID:27775606
el Kady, G A; Shoukry, A; Ragheb, D A; el Said, A M; Habib, K S; Morsy, T A
Mites are arthropods distinguished from ticks by usually being microscopical in size and have a hypostome unarmed with tooth-like anchoring processes. They are group in a number of suborders, each with super-families and families including many genera of medical and economic importance. In this paper, commensal rodents (Rattus norvegicus, R. r. alexandrinus and R. r. frugivorous) were surveyed in the Suez Canal Zone for their acari ectoparasites. Four species of mites were recovered. In a descending order of mite indices, they were Eulaelaps stabularis (4.83 on 6 rats), Laelaps nuttalli (3.11 on 27 rats), Ornithonyssus bacoti (1.66 on 9 rats) and Dermanyssus gallinae (0.66 on 24 rats). The overall mite indices in the three governorates were 3.66 in Suez, 2.82 in Ismailia and zero in Port Said. The medical and economic importance of the mites were discussed.
et al. 1998). Oliver et al. (1987) described the immature stages of I. affinis and provided distribution, phenology , and host records. Ixodes...Ixodes (Ixodes) scapularis (Acari: Ixodidae): Redescription of all active stages, distribution, hosts, geographical variation , and medical and
Tbrahim Cakmak; Tulin Aksit; Sultan Cobanoglu
Pyemotes johnmoseri (Khaustov) (Acari: Pyemotidae) was collected from Hypoborus ficus (Erichson) and Hesperophanes griseus Fab. (Col.: Cerambycidae) in fig (Ficus carica cv Calymirna) orchards in Aydin, Turkey during 2003-2004. We describe and illustrate the male and female of P. ...
Khaustov, Alexander A
Two new species of the genus Pediculaster Vitzthum, 1931 (Acari: Pygmephoroidea: Pygmephoridae), P. ermilovi sp. nov. and P. lignarius sp. nov. are described from rotten logs in Tyumen, Western Siberia, Russia. A key to phoretic females of Palaearctic species of the genus Pediculaster is provided.
Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae) is a polyphagous mite with worldwide distribution and it is also a vector of several plant viruses. In citrus, B. phoenicis transmits Citrus leprosis virus (CiLV), the causal agent of leprosis, a disease that costs millions of dollars/year for ...
Stanislav Klauz; Peter Masan; John C. Moser
The deutonymphal stage and adults of Schizosthetus simulatrix Athias- Henriot, 1982 (Acari, Mesostigmata, Parasitidae), originally known from Canary Islands and Portugal, has been illustrated and described or redescribed, respectively. The subadults of S. simulatk have not previously been described. This very specialised subcorticolous species lives in galleries of...
Saboori, Alireza; Wohltmann, Andreas; Hakimitabar, Masoud; Shirvani, Asghar
Achaemenothrombium dariusi Saboori, Wohltmann & Hakimitabar sp. nov. (Acari, Prostigmata: Trombidioidea) is described and illustrated from larvae ectoparasitic on Euxoafallax (Eversmann) (Lepidoptera: Noctuidae) from Sirch and Cheshmeh Bondar, Kerman province, Iran. It is the third species of this genus, which is recorded only from Iran. The status of this small family is discussed and a key to species of A chaemenothrombium (larvae) is presented.
The brown dog tick can be a serious residential pest due to its unique ability, among ticks, to complete its lifecycle indoors. A single engorged and fertilized female tick can oviposit around 4,000 eggs, allowing indoor establishment to be rapid and easy to miss in early-stage infestations. Acari...
Investigations have been conducted in Europe in the last decade in order to find potential agents for biological control of invasive teasels in North America. During surveys conducted in Serbia in May 2007, the new eriophyid mite species Aculops dipsaci n. sp. (Acari: Prostigmata: Eriophyidae) was ...
Proper identification of mites (Arachnida: Acari) require preparation of the specimen on a microscope slide. This training video provides visual instruction on how to prepare mite specimens on microscope slides for examination and identification. Steps ranging from collection, specimen clearing, use...
Stored product mites (Acari: Acaridida) can often infest stored products, but currently there is little information regarding efficacy of insecticides or miticides that can be used for control. In this study we evaluated several common insecticides (chlorpyrifos, deltametrhin, beta-cyfluthrin, and a...
Haitlinger, Ryszard; Łupicki, Dariusz
From 9 specimens of Procyon lotor collected in vicinity of Dobroszyn and Górzyca (Lubuskie province) 61 arthropods of 6 species were obtained: Siphonaptera (one specimen), Acari (3 species), Phthiraptera (one specimen--Trichodectes octomaculatus; new species to fauna of Poland) and one specimen of Psocoptera.
Alberto B. Broce; Ludek Zurek; James A. Kalisch; Robert Brown; David L. Keith; David Gordon; Janis Geodeke; Cal Welbourn; John Moser; Ronald Ochoa; Eduardo Azziz-Baumgartner; Fuyuen Yip; Jacob Weber
High incidences of red, itching, and painful welts on people in the midwestern United States led to the discovery of a European species of mite, Pyemotes herfsi (Oudemans) (Acari: Pyemotidae), preying on gall-making midge larvae on oak leaves. The mites' great reproductive potential, small size, and high capacity for dispersal by wind make them...
Xu, Yun; Fan, Qing-Hai; Huang, Jian
A new species Terminalichus sanya Xu & Fan sp. nov. (Acari: Tenuipalpidae) on Terminalia catappa L. (Combretaceae) from China is described and illustrated. The ontogenetic changes in ventral and leg chaetotaxy on the female, deutonymph, protonymph and larva are presented. The generic definition of Terminalichus is updated and a key to the world species is provided.
Staňková, Kateřina; Abate, Alessandro; Sabelis, Maurice W
We propose an optimal control framework to describe intra-seasonal predator-prey interactions, which are characterized by a continuous-time dynamical model comprising predator and prey density, as well as the energy budget of the prey over the length of a season. The model includes a time-dependent decision variable for the prey, representing the portion of the prey population in time that is active, as opposed to diapausing (a state of physiological rest). The predator follows autonomous dynamics and accordingly it remains active during the season. The proposed model is a generalization of the classical Lotka-Volterra predator-prey model towards non-autonomous dynamics that furthermore includes the effect of an energy variable. The model has been inspired by a specific biological system of predatory mites (Acari: Phytoseiidae) and prey mites (so-called fruit-tree red spider mites) (Acari: Tetranychidae) that feed on leaves of apple trees--its parameters have been instantiated based on laboratory and field studies. The goal of the work is to understand the decisions of the prey mites to enter diapause (a state of physiological rest) given the dynamics of the predatory mites: this is achieved by solving an optimization problem hinging on the maximization of the prey population contribution to the next season. The main features of the optimal strategy for the prey are shown to be that (1) once in diapause, the prey does not become active again within the same season and hence diapause is an irreversible process; (2) for the vast majority of parameter space, the portion of prey individuals entering diapause within the season does not decrease in time; (3) with an increased number of predators, the optimal population strategy for the prey is to start diapause earlier and to enter diapause more gradually. This optimal population strategy will be studied for its ESS properties in a sequel to the work presented in this article.
Hu, Yue; Wang, Boming; Chen, Xi; Xu, Xuenong; Wang, Endong
Amblyseius orientalis (Ehara) (Acari: Phytoseiidae) is a native predatory mite species in China. It used to be considered as a specialist predator of spider mites. However, recent studies show it also preys on other small arthropod pests, such as Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Experiments were conducted to investigate (1) prey preference of A. orientalis between Tetranychus cinnabarinus (Boisd.) (Acari: Tetranychidae) and B. tabaci, and (2) development, consumption and life table parameters of A. orientalis when reared on T. cinnabarinus, B. tabaci or a mix of both prey species. When preying on different stages of T. cinnabarinus, A. orientalis preferred protonymphs, whereas when preying on different stages of B. tabaci, A. orientalis preferred eggs. When these two most preferred stages were provided together (T. cinnabarinus protonymphs and B. tabaci eggs), A. orientalis randomly selected its prey. Amblyseius orientalis was able to complete its life cycle on B. tabaci eggs, T. cinnabarinus protonymphs, or a mix of both prey. However, its developmental duration was 53.9% and 30.0% longer when reared on B. tabaci eggs than on T. cinnabarinus and a mix of both prey, respectively. In addition, it produced only a few eggs and its intrinsic rate of increase was negative when reared on B. tabaci eggs, which indicates that B. tabaci is not sufficient to maintain A. orientalis population. The intrinsic rates of increase were 0.16 and 0.23 when A. orientalis was fed on the prey mix and T. cinnabarinus, respectively. These results suggest that although B. tabaci is a poor food resource for A. orientalis in comparison to T. cinnabarinus, A. orientalis is able to sustain its population on a mix of both prey. This predatory mite may thus be a potential biological control agent of B. tabaci when this pest co-occurs with the alternative minor pest T. cinnabarinus. PMID:26436422
Koveos, Dimitrios S; Suzuki, Takeshi; Terzidou, Anastasia; Kokkari, Anastasia; Floros, George; Damos, Petros; Kouloussis, Nikos A
Egg hatchability of four predatory mites-Phytoseiulus persimilis Athias-Henriot, Iphiseius [Amblyseius] degenerans Berlese, Amblyseius swirskii Athias-Henriot, and Euseius finlandicus Oudemans (Acari: Phytoseiidae)-and the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) was determined under various UV-B doses either in constant darkness (DD) or with simultaneous irradiation using white light. Under UV-B irradiation and DD or simultaneous irradiation with white light, the predator's eggs hatched in significantly lower percentages than in the control non-exposed eggs, which indicates deleterious effects of UV-B on embryonic development. In addition, higher hatchability percentages were observed under UV-B irradiation and DD in eggs of the predatory mites than in eggs of T. urticae. This might be caused by a higher involvement of an antioxidant system, shield effects by pigments or a mere shorter duration of embryonic development in predatory mites than in T. urticae, thus avoiding accumulative effects of UV-B. Although no eggs of T. urticae hatched under UV-B irradiation and DD, variable hatchability percentages were observed under simultaneous irradiation with white light, which suggests the involvement of a photoreactivation system that reduces UV-B damages. Under the same doses with simultaneous irradiation with white light, eggs of T. urticae displayed higher photoreactivation and were more tolerant to UV-B than eggs of the predatory mites. Among predators variation regarding the tolerance to UV-B effects was observed, with eggs of P. persimilis and I. degenerans being more tolerant to UV-B radiation than eggs of A. swirskii and E. finlandicus.
Audenaert, J; Vangansbeke, D; Verhoeven, R; De Clercq, P; Tirry, L; Gobin, B
Predatory mites like Phytoseiulus persimilis Athias-Henriot, Neoseiulus californicus McGregor and N. fallacis (Garman) (Acari: Phytoseiidae) are essential in sustainable control strategies of the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) in warm greenhouse cultures to complement imited available pesticides and to tackle emerging resistance. However, in response to high energy prices, greenhouse plant breeders have recently changed their greenhouse steering strategies, allowing more variation in temperature and humidity. The impact of these variations on biological control agents is poorly understood. Therefore, we constructed functional response models to demonstrate the impact of realistic climate variations on predation efficiency. First, two temperature regimes were compared at constant humidity (70%) and photoperiod (16L:8D): DIF0 (constant temperature) and DIF15 (variable temperature with day-night difference of 15°C). At mean temperatures of 25°C, DIF15 had a negative influence on the predation efficiency of P. persimilis and N. californicus, as compared to DIF0. At low mean temperatures of 15°C, however, DIF15 showed a higher predation efficiency for P. persimilis and N. californicus. For N. fallacis no difference was observed at both 15°C and 25°C. Secondly, two humidity regimes were compared, at a mean temperature of 25°C (DIFO) and constant photoperiod (16L:8D): RHCTE (constant 70% humidity) and RHALT (alternating 40% L:70%D humidity). For P. persimilis and N. fallacis RHCTE resulted in a higher predation efficiency than RHALT, for N. californicus this effect was opposite. This shows that N. californicus is more adapted to dry climates as compared to the other predatory mites. We conclude that variable greenhouse climates clearly affect predation efficiency of P. persimilis, N. californicus and N. fallacis. To obtain optimal control efficiency, the choice of predatory mites (including dose and application frequency
Martínez, Leocadia Sánchez; Flechtmann, Carlos H W; De Moraes, Gilberto J
Fourteen mite species of plant-associated mites of the suborder Prostigmata are reported from the Dominican Republic. Four of these refer to new findings for the country, including Petrobia (Tetranychina) hispaniola n. sp. Sánchez & Flechtmann, described from specimens collected from leaves of Citrus sp. (Rutaceae) and Rosa sp. (Rosaceae). A key for the separation of the world species of Petrobia (Tetranychina) is presented.
Phylogenetic analysis of the spider mite sub-family Tetranychinae (Acari: Tetranychidae) based on the mitochondrial COI gene and the 18S and the 5' end of the 28S rRNA genes indicates that several genera are polyphyletic.
Matsuda, Tomoko; Morishita, Maiko; Hinomoto, Norihide; Gotoh, Tetsuo
The spider mite sub-family Tetranychinae includes many agricultural pests. The internal transcribed spacer (ITS) region of nuclear ribosomal RNA genes and the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA have been used for species identification and phylogenetic reconstruction within the sub-family Tetranychinae, although they have not always been successful. The 18S and 28S rRNA genes should be more suitable for resolving higher levels of phylogeny, such as tribes or genera of Tetranychinae because these genes evolve more slowly and are made up of conserved regions and divergent domains. Therefore, we used both the 18S (1,825-1,901 bp) and 28S (the 5' end of 646-743 bp) rRNA genes to infer phylogenetic relationships within the sub-family Tetranychinae with a focus on the tribe Tetranychini. Then, we compared the phylogenetic tree of the 18S and 28S genes with that of the mitochondrial COI gene (618 bp). As observed in previous studies, our phylogeny based on the COI gene was not resolved because of the low bootstrap values for most nodes of the tree. On the other hand, our phylogenetic tree of the 18S and 28S genes revealed several well-supported clades within the sub-family Tetranychinae. The 18S and 28S phylogenetic trees suggest that the tribes Bryobiini, Petrobiini and Eurytetranychini are monophyletic and that the tribe Tetranychini is polyphyletic. At the genus level, six genera for which more than two species were sampled appear to be monophyletic, while four genera (Oligonychus, Tetranychus, Schizotetranychus and Eotetranychus) appear to be polyphyletic. The topology presented here does not fully agree with the current morphology-based taxonomy, so that the diagnostic morphological characters of Tetranychinae need to be reconsidered.
Younis, T A; Fayad, M E; el Hariry, M A; Morsy, T A
From the medical point of view, the relation between man and rodents comes in the priority. Some rodent populations are wild but others are commensal and live in close association with man. They steal his food and conveying many zoonotic diseases. Their arthropod ectoparasites play an important role in conveying or transmitting these zoonotic diseases. Several disorders and diseases of man are tick borne relapsing fever, Rocky mountain spotted fever, Lyme disease, and many others. Besides numerous species of mites occasionally infest man. They transmit several diseases as Rickettsia tsutsugamushi fever, epidemic haemorrhagic fever, and they cause severe allergic reaction. The results obtained are summarized in the following (1) Six species and subspecies of rodents were detected. In a descending order of abundance, they were (a) Rattus norvegicus, (b) Rattus rattus alexandrinus (c) Rattus rattus frugivorous (d) Acomys cahirinus (e) Gerbillus gerbillus asyutensis (f) Mus m. praetextus. (2) The most common rodent was R. norvegicus and the least common was M. musculus. (3) The collected ticks and mites were 2 genera of tick larvae; Rhipicephalus species and Hyalomma species. The collected mites were Ornithonyssus bacoti and Laelaps nuttali. (4) Most of the tick larvae were collected from wild rodents; Gerbillus g. asyutensis. (5) Most of the mites were collected from commensal rodents particularly R. norvegicus. Descriptive morphology and illustrations were given to the collected rodents and their acari ectoparasites.
Bochkov, A V; Fain, A; Skoracki, M
Five new species and two new genera belonging to the family Syringophilidae (Acari: Cheyletoidea) are described from birds that died in the Antwerp Zoo during their quarantine: Charadriaulobia vanelli n. g., n. sp. from Vanellus chilensis (Charadriiformes: Charadriidae) in Brazil; Fritschisyringophilus lonchurae n. g., n. sp. from Lonchura punctulata (Passeriformes: Estrildidae) in India; Mironovia coturnae n. sp. from Coturnix coturnix (Galliformes: Phasianidae) in Europe; Syringophiloidus daberti n. sp. from Passerina ciris (Passeriformes: Emberizidae) in Mexico; and S. serini n. sp. from Serinus mozambicus (Passeriformes: Fringillidae) in Central Africa. Charadriaulobia n. g. differs from the closely related Aulobia Kethley, 1970, in both sexes, by the divergent epimeres I; in females, by the absence of protuberances on the hypostomal apex and by the situation of the bases of setae l4 distinctly anterior the bases of setae d4. Fritschisyringophilus n. g. differs from the closely related Syringophiloidus Kethley, 1972, in both sexes, by the presence of setae vs ' on legs II, the absence of setae dT on legs III and IV; in females, by the presence of median hypostomal protuberances and by short setae l1, l2 and l3. The relationships between the Syringophilidae and their hosts are briefly discussed. A list of all known syringophilid genera and their distribution on bird families is provided.
Pešić, Vladimir; Smit, Harry
New records of water mites of the family Torrenticolidae (Acari: Hydrachnidia) from streams in two mountain ranges in northern Borneo are presented. Aims of this study were to reconstruct phylogenetic relationships of the newly collected torrenticolids using molecular methods, and describe all new species. A fragment of the mtCOI gene was successfully PCR-amplified from 18 torrenticolid specimens and 14 new species are described: Torrenticola (Torrenticola) borneoensis n. sp., T. (T.) kinabaluensis n. sp., T. (T.) sabahensis n. sp., T. (T.) neoindica n. sp., T. (T.) schilthuizeni n. sp., Neoatractides (Allotorrenticola) sundaensis n. sp., N. (Heteratractides) uniscutatus n. sp., Pseudotorrenticola borneoensis n. sp., Monatractides (Monatractides) epiales n. sp., M. (M.) morpheus n. sp., M. (M.) phantasos n. sp., M. (M.) phobetor n. sp., M. (M.) hercules n. sp. and M. (M.) minuta n. sp. Additionally, the first records for Borneo are given for Torrenticola (Megapalpis) cf. pugionirostris (K. Viets, 1939), Monatractides (Monatractides) longiventris (K. Viets, 1939), M. (M.) cf. macroporus (K. Viets, 1935) and M. (M.) oxystomus (K. Viets, 1935). Monatractides tobaensis (K. Viets, 1935) is transferred to the subgenus Vietsclio Pešić & Smit, 2014. A key to the species of Monatractides is presented.
Glowska, Eliza; Dragun-Damian, Anna; Dabert, Miroslawa; Gerth, Michael
Wolbachia is the most abundant intracellular bacterial genus infecting a wide range of arthropods and filarial nematodes. Wolbachia have evolved parasitic, mutualistic and commensal relationships with their hosts but in arthropods generally act as reproductive parasites, inducing a wide range of phenotypic effects such as cytoplasmic incompatibility, parthenogenesis, feminization and male-killing. Up to now, the genus has been divided into 14 supergroups successively named A-O. Here, we describe two new Wolbachia supergroups from syringophilid mites (Acari: Cheyletoidea). These obligatory ectoparasites of birds inhabit the quills of feathers in many avian groups. The species of this family reproduce in a haplodiploid mode sensu arrhenotoky and are usually strongly female-biased. Based on the sequences of four protein-coding genes (ftsZ, gltA and groEL and coxA) and the 16S rRNA we identified strains of three Wolbachia supergroups (F and two distinct, yet undescribed ones) in five quill mite species. Our results suggest that in some cases the distribution of the bacteria can be better correlated with the mite's bird host rather than with mite taxonomy as such. The discovery of two new Wolbachia supergroups not only broadens the knowledge of the diversity of this bacterium but also raises questions about potential effects induced in quill mites and transmission mechanisms of the endosymbionts in this peculiar bacteria-quill mite-bird system. Copyright © 2014 Elsevier B.V. All rights reserved.
MENTZ, Márcia Bohrer; TROMBKA, Marcelo; da SILVA, Guilherme Liberato; SILVA, Carlos Eugênio
We report the finding of a female brown dog tick, Rhipicephalus sanguineus (Acari: Ixodidae) on the scalp of a male patient in Porto Alegre, Rio Grande do Sul, Brazil. Human parasitism by this tick is rare and has seldomly been reported in the literature, despite its recognized importance since it can act as a vector of Rickettsia rickettsii, the agent of spotted fever. PMID:27074329
Nemati, Alireza; Joharchi, Omid; Babaeian, Esmaeil; Gwiazdowicz, Dariusz J
We describe a new species of mite from Iran--Reticulolaelaps hallidayi Joharchi, Nemati & Babaeian sp. nov. (Acari: Laelapidae). The new species was collected in a nest of Tapinoma sp. (Hymnoptera: Formicidae) in Taleghan city, Alborz Province and in soil in Khuzestan province in southwestern Iran. Reticulolaelapsfaini is reported for the first time from Iran. The genus Reticulolaelaps is redescribed, and Reticulolaelaps lativentris Karg is transferred to Pseudoparasitus Oudemans.
Saeidi, Zarir; Nemati, Alireza; Khalili-Moghadam, Arsalan
Abstract A new species of Gaeolaelaps (Acari, Mesostigmata, Laelapidae), Gaeolaelaps izajiensis sp. n. is described based on the morphological characters of adult females which were collected from soil sample in the Izeh and Ghaletol regions of the Khuzestan province, Iran. It can be distinguished from the other members of the genus by some morphological characteristics of dorsal shield, form and reticulation of epigynal shield, the exopodal plates, and the peritremes. PMID:27667922
Khaustov, Alexander A.
Abstract Five species of myrmecophilous microdispid mites (Acari: Microdispidae) are recorded from Western Siberia, Russia. Unguidispus lasii Kurosa, 1979, Unguidispus japonicus Kurosa, 1979, Caesarodispus minutus (Sevastianov, 1981), and Caesarodispus samsinaki (Mahunka, 1967), comb. n. are reported from Russia for the first time. Unguidispus polyctenus (Sevastianov, 1969) and Caesarodispus samsinaki are redescribed. The keys to species of the genera Unguidispus Mahunka, 1970 and Caesarodispus Mahunka, 1977 are provided. PMID:25493064
Mites of the family Myocoptidae and Listrophoridae (Acari: Astigmata) are permanent, mono- or oligoxenous ectoparasites of mammals. Only 9 species from 4 genera of Myocoptidae are reported in Poland, as well 6 species from 4 genera of Listrophoridae, which are only a small fraction of huge number of these mites known in the world. This paper summarize known data about morphological features being adaptation of Myocoptidae and Listrophoridae to parasitize fur of mammals.
Ernst Ebermann; John C. Moser
Four species of Scutacarus and one of Imparipes (Acari: Scutacaridae) are documented as phoretic from alates and workers of the red imported fire ant (Solenopsis invicta Buren) in Louisiana and Tennessee, U.S.A. One, Imparipes (Imparipes) louisianae)
The southern cattle fever tick, Rhipicephalus (Boophilus) microplus (Canestrini), is a haematophagous arachnid (Acari: Ixodidae) recognized globally as an economically important ectoparasite of cattle in tropical and subtropical agroecosystems. Populations of this invasive tick species around the wo...
Labruna, Marcelo B; Jorge, Rodrigo S P; Sana, Dênis A; Jácomo, Anah Tereza A; Kashivakura, Cyntia K; Furtado, Mariana M; Ferro, Claudia; Perez, Samuel A; Silveira, Leandro; Santos, Tarcísio S; Marques, Samuel R; Morato, Ronaldo G; Nava, Alessandra; Adania, Cristina H; Teixeira, Rodrigo H F; Gomes, Albério A B; Conforti, Valéria A; Azevedo, Fernando C C; Prada, Cristiana S; Silva, Jean C R; Batista, Adriana F; Marvulo, Maria Fernanda V; Morato, Rose L G; Alho, Cleber J R; Pinter, Adriano; Ferreira, Patrícia M; Ferreira, Fernado; Barros-Battesti, Darci M
The present study reports field data of ticks infesting wild carnivores captured from July 1998 to September 2004 in Brazil. Additional data were obtained from one tick collection and from previous published data of ticks on carnivores in Brazil. During field work, a total of 3437 ticks were collected from 89 Cerdocyon thous (crab-eating fox), 58 Chrysocyon brachyurus (maned wolf), 30 Puma concolor (puma), 26 Panthera onca (jaguar), 12 Procyon cancrivorus (crab-eating raccoon), 4 Speothos venaticus (bush dog), 6 Pseudalopex vetulus (hoary fox), 6 Nasua nasua (coati), 6 Leopardus pardalis (ocelot), 2 Leopardus tigrinus (oncilla), 1 Leopardus wiedii (margay), 1 Herpailurus yagouaroundi (jaguarundi), 1 Oncifelis colocolo (pampas cat), 1 Eira barbara (tayara), 1 Galictis vittata (grison), 1 Lontra longicaudis (neotropical otter), and 1 Potus flavus (kinkajou). Data obtained from the Acari Collection IBSP included a total of 381 tick specimens collected on 13 C. thous, 8 C. brachyurus, 3 P. concolor, 10 P. onca, 3 P. cancrivorus, 4 N. nasua, 1 L. pardalis, 1 L. wiedii, 4 H. yagouaroundi, 1 Galictis cuja (lesser grison), and 1 L. longicaudis. The only tick-infested carnivore species previously reported in Brazil, for which we do not present any field data are Pseudalopex gymnocercus (pampas fox), Conepatus chinga (Molina's hog-nosed skunk), and Conepatus semistriatus (striped hog-nosed skunk). We report the first tick records in Brazil on two Felidae species (O. colocolo, H. yagouaroundi), two Canidae species (P. vetulus, S. venaticus), one Procyonidae species (P. flavus) and one Mustelidae (E. barbara). Tick infestation remains unreported for 5 of the 26 Carnivora species native in Brazil: Oncifelis geoffroyi (Geoffroy's cat), Atelocynus microtis (short-eared dog), Pteronura brasiliensis (giant otter), Mustela africana (Amazon weasel), and Bassaricyon gabbii (olingo). Our field data comprise 16 tick species represented by the genera Amblyomma (12 species), Ixodes (1
Although coconut (Cocos nucifera L.) is the predominant host for Raoiella indica Hirst (Acari: Tenuipalpidae), false spider mite infestations do occur on bananas and plantains (Musa spp. Colla). Since its introduction, the banana and plantain industries have been negatively impacted to different deg...
Mayoral, Jaime G; Barranco, Pablo
Nevada capileirarum n. g., n. sp. (Acari: Microtrombidiidae: Microtrombidiinae) is described from ectoparasitic larvae parasitising two endemic species of Orthoptera (Tettigoniidae), Baetica ustulata (Rambur) and Pycnogaster inermis (Rambur) from the Sierra Nevada mountain range, Granada, Spain. A key to the larvae of microtrombidiine genera with three dorsal scuta and a coxal setal formula of 2-1-1 is presented.
Mayoral, Jaime G; Barranco, Pablo
Alhamitrombium tetraseta n. g., n. sp. (Acari: Eutrombidiidae: Eutrombidiinae) is described from two larvae ectoparasitic on Trymosternus bolivari Mateu (Coleoptera: Carabidae) from Almería, Spain. The new genus is distinguished from Hexathrombium Cooreman, 1944 and Beronium Southcott, 1986 on the basis of details of the coxalae. A key to the genera of larval Hexathrombiini is presented.
Mašán, Peter; Özbek, Hasan Hüseyin; Fenďa, Peter
Abstract Pachylaelaps (Pachylaelaps) pyrenaicus sp. n. and Pachylaelaps (Longipachylaelaps) brevipilis sp. n. (Acari, Pachylaelapidae) are described and illustrated based on specimens from litter and soil detritus of forest habitats in Spain (Pyrenees Mts) and Portugal (Serra da Labruja Mts), respectively. An identification key to European species of the genus Pachylaelaps Berlese, 1888 is provided. PMID:27551197
Joharchi, Omid; Halliday, Bruce; Beyzavi, Gholamreza
We describe a new species of mite from Iran - Pronacrolaelaps propomacrus sp. nov. (Acari: Laelapidae). The new species was collected in association with the beetle Propomacrus bimucronatus (Pallas) (Coleoptera: Scarabaeidae: Euchirinae) in holes in the trunk of oak trees. The genus Promacrolaelaps is redescribed and distinguished from the related genus Hypoaspis Canestrini sells. strict.
Michael A. Camann; Nancy E. Gillette; Karen L. Lamoncha; Sylvia R. Mori
We studied responses of Acari, especially oribatid mites, to prescribed low-intensity fire in an east side pine site in the southern Cascade Range in California. We compared oribatid population and assemblage responses to prescribed fire in stands that had been selectively logged to enhance old growth characteristics, in logged stands to minimize old growth...
Skorack, Maciej; Klimovičová, Miroslava; Muchai, Muchane; Hromada, Martin
New taxa of quill mites (Acari: Syringophilidae) are described from African barbets and woodpeckers in the Ethiopian region. A new monotypic genus Picineoaulonastus gen. nov. is established for a new species Picineoaulonastus pogoniulus sp. nov., parasitising 2 lybiid species, Pogoniulus bilineatus (Sundevall) (type host) in Kenya and Tanzania and P. pusillus (Dumont) (Piciformes: Lybiidae) in Ethiopia. Additionally, 2 more new syringophilid species are described: Neosyringophilopsis lybidus sp. nov. from P. bilineatus in Kenya, and Syringophiloidus picidus sp. nov. from Dendropicos fuscescens (Vieillot) (Piciformes: Picidae) in Kenya, Uganda, and Tanzania.
Khaustov, Alexander A; Tolstikov, Andrei V
A new species of the genus Eustigmaeus Berlese, 1910 (Acari: Stigmaeidae), E. tjumeniensis sp. nov. is described from mosses of fens in Western Siberia, Russia. Eutigmaeus collarti (Cooreman, 1955), E. ioanninensis Kapaxidi and Papadoulis, 1999, E. jiangxiensis Hu, Chen and Huang, 1996 are recorded from Russia for the first time. Eustigmaeus parvisetus (Chaudhri, 1965) is recorded from Eurasia for the first time. Eustigmaeus collarti and E. parvisetus are redescribed based on material from Western Siberia. A key to Eustigmaeus species of Russia is provided.
Gonçalves-Souza, Thiago; Giupponi, Alessandro P L; Hernandes, Fabio A
Twelve larvae of unidentified species of Odontacarus Ewing, 1929 (Acari: Leeuwenhoekiidae) were found parasitising an adult male whip spider Charinus brasilianus Weygoldt (Charinidae) in Santa Teresa, mountainous region of Espirito Santo state, southeastern Brazil. These larvae occurred in the intersegmental membrane of prosoma and legs. This is the first report of ectoparasitic mites infecting a charinid whip spider and the first record of leeuwenhoekiid mites parasitising an invertebrate host. We suggest that future studies are essential to understand the reasons why these events of parasitism are so rare in the order Amblypygi.
Joharchi, Omid; Mašán, Peter; Babaeian, Esmaeil
The new genus Pedoniphis gen. nov. (Acari: Mesostigmata: Eviphididae) is described from soil detritus in Sabalan Mountains, northwest Iran, with P. persicus sp. nov. as type species. Among known eviphidid genera, the new genus is the most similar to Scamaphis Karg and Scarabacariphis Mašán and it can be distinguished especially by the dorsal chaetotaxy (setae J2 absent, setae J5 rudimentary) and the specific form of the peritrematal-dorsal scutal complex (peritrematal shields reduced; peritremes well developed, fused to lateral margins of dorsal shield).
Darbemamieh, Maryam; Hajiqanbar, Hamidreza; Khanjani, Mohammad; Kaźmierski, Andrzej
In this paper, Neopronematus kamalii Darbemamieh and Hajiqanbar sp. nov. (Acari: Prostigmata: Iolinidae), collected from apricot leaves in Kermanshah province, Iran, is described and illustrated. Also, the following species were collected and identified from Kermanshah province, Iran: Neopronematus rapidus (Kuznetzov, 1972), Neopronematus solani Łaniecka and Kaźmierski, 2013; Neopronematus sepasgosariani Sadeghi, Łaniecka and Kaźmierski, 2012; Neopronematus lundqvisti Sadeghi, Łaniecka and Kaźmierski, 2012; and Neopronematus neglectus (Kuznetzov, 1972). Some information about the genus, morphologically close species, remarks and a key to Neopronematus species of the world are given as well.
Pešić, Vladimir; Gerecke, Reinhard
Four species of water mites (Acari, Hydrachnidia) were collected in 2010 during an Italian speleological expedition to caves of the Ha Giang region in northern Vietnam from rimstone pools or other tiny accumulations of percolating water. Four taxa new to science are described, representing the families Torrenticolidae (Torrenticola anophthalma nov. sp., Stygotorrenticola coniseta nov. gen., nov. sp.), Limnesiidae (Raptorhydracarinae subfam. nov., Raptorhydracarus tomasini nov. gen., nov sp.) and Athienemanniidae (Africasia vietnamitica sp. nov.). Most of these taxa show striking morphological adaptations to subterranean life.
Lebedeva, Natalia V; Poltavskaya, Marina P
The paper is devoted to the fauna of oribatid mites (Acari: Oribatida) mostly of a plain area of the Southern European Russia. The most updated taxonomic list of oribatid mite taxa compiled from the original authors' data collected after sam- pling soil, nests and plumage of birds, as well as published sources is presented. It includes 256 species of oribatid mites belonging to 72 families. Twenty species and one family of oribatid mites are recorded for the first time at the research territory. The abundance of mites in the soil is also provided for selected species.
Horak, Ivan G; Apanaskevich, Dmitry A; Kariuki, Edward K
A new tick species belonging to the genus Rhipicephalus Koch, 1844 (Acari: Ixodidae), namely, Rhipicephalus walkerae n. sp., is described. The male and female of this species are similar to those of several species in the Rhipicephalus appendiculatus group but can be distinguished from them by the very dense pattern of medium-sized punctations covering the conscutum and scutum, long and narrow dorsal prolongation of the spiracular plate, and relatively short dorsal cornua; in addition, the male has long and narrow adanal plates without a posterolateral angle. R. walkerae is known only from Kenya, where the adults were collected from giraffes, Giraffa camelopardalis (L.).
Rosado, Jander F; Picanço, Marcelo C; Sarmento, Renato A; da Silva, Ricardo Siqueira; Pedro-Neto, Marçal; Carvalho, Marcos Alberto; Erasmo, Eduardo A L; Silva, Laila Cristina Rezende
Studies on the seasonal variation of agricultural pest species are important for the establishment of integrated pest control programs. The seasonality of pest attacks on crops is affected by biotic and abiotic factors, for example, climate and natural enemies. Besides that, characteristics of the host plant, crop management, location and the pests' bioecology also affect this seasonality. The mites Polyphagotarsonemus latus (Prostigmata: Tarsonemidae) and Tetranychus bastosi (Prostigmata: Tetranychidae) are the most important pests in the cultivation of physic nut, Jatropha curcas (Euphorbiaceae). All parts of J. curcas can be used for a wide range of purposes. In addition many researchers have studied its potential for use as neat oil, as transesterified oil (biodiesel), or as a blend with diesel. However studies about physic nut pests have been little known. The objective of this study was to assess the seasonal variation of P. latus and T. bastosi in physic nut. This study was conducted at three sites in the state of Tocantins, Brazil. We monitored climatic elements and the densities of the two mite species and of their natural enemies for a period of 2 years. Attack by P. latus occurred during rainy seasons, when the photoperiod was short and the physic nut had new leaves. In contrast, attack by T. bastosi occurred during warmer seasons with longer photoperiods and stronger winds. Populations of both mites and their natural enemies were greater in sites with greater plant diversity adjacent to the plantations. The predators found in association with P. latus and T. bastosi were Euseius concordis (Acari: Phytoseiidae), spiders, Stethorus sp. (Coleoptera: Coccinellidae) and Chrysoperla sp. (Neuroptera: Chrysopidae).
Xu, Yun; Zhang, Zhi-Qiang
The genus Prolixus (Acari: Tenuipalpidae) was represented by two species from Australian sedges prior to this study. A new species, Prolixus meyerae sp. nov., is here described and illustrated from leaves of Gahnia (Cyperaceae) in Auckland, New Zealand. In this paper, we present the ontogenetic additions in idiosomal and leg chaetotaxy from larva to adult. A key to world species of Prolixus is also proposed.
encephalitis virus complex) viruses by Onithodoros ticks (Acari: Argasidae), Journal of Medical Entomology 41:973 - 977 5a. CONTRACT NUMBER 5b. GRANT NUMBER...mosquitoes and Ornithodoros ticks were evaluated for their potential to transmit Karshi and Langat (tick-borne encephalitis virus complex) viruses in the...suckling mice. In addition, female O. tartakovskyi transmitted Karshi virus vertically to their progeny. In a continuation of a previous study, O. sonrai
Hajiqanbar, Hamidreza; Khaustov, Alexander; Kamali, Karim
A new species of the genus Parapygmephorus Cross, 1965 (Acari: Heterostigmatina, Neopygmephoridae) is described from Northeastern Iran. A phoretic adult female of Parapygmephorus khorasanicus Hajiqanbar and Khaustov sp. n. was discovered clasping on hairs on the ventral body surface of Halictus quadricinctus (Fabricius, 1776) (Hymenoptera; Halictidae). It is the fifth representative among the known species of the genus Parapygmephorus in the world. Differentiation of new species from other species of the genus is discussed, and a key to known world species is provided.
Farzan, Sadegh; Asadi, Mahdieh; Ueckermann, Edward A; Seeman, Owen D; Beard, Jennifer J
Two new species of Amblypalpus (Acari: Trombidiformes: Tenuipalpidae) are described from Iran: Amblypalpus iraniensis sp. nov., from Wild Almond, Amygdalus scoparia (Rosaceae), and Amblypalpus thymus sp. nov., from Common Thyme, Thymus vulgaris (Lamiaceae). The new species are classified tentatively in Amblypalpus. The species Priscapalpus thomissus Meyer, 1979 is transferred to Amblypalpus and the genus concept of Priscapalpus is narrowed and therefore redefined. Similarly, we present an expanded concept of Amblypalpus. A key to brevipalpine genera and Amblypalpus species is provided.
Trach, Viacheslav A; Seeman, Owen D
A new genus and species of Schizogyniidae (Acari: Mesostigmata: Celaenopsoidea), Euroschizogynium calvum gen. nov. and sp. nov., associated with Scarites terricola Bonelli, 1813 (Coleoptera: Carabidae) is described from Ukraine, representing the first record of the family from the Palaearctic. Fusura civica Valle & Fox, 1966 is moved out of the Schizogyniidae and placed into the Megacelaenopsidae. A new diagnosis for the family Schizogyniidae and a key to genera are provided.
Seeman, Owen D; Baker, Michelle R
Berzercon ferdinandi gen. nov., sp. nov. (Acari: Mesostigmata: Discozerconidae) is described from carabid beetles in New Zealand. As in all Discozerconidae, Berzercon has large ventrally-directed opisthogastric suckers. However it is distinctive in its long marginal setae, tripartite gnathotectum, fused palp tibia and tarsus, the female's large dome-shaped genital shield and the male's highly modified hypostomal seta h1. This new species also represents the first Heterozerconina from an insect host.
Haitlinger, Ryszard; Piksa, Krzysztof
Spinturnix bechsteini Deunff et al., 2004 (Acari: Spinturnicidae) associated with Myotis bechsteinii (Kuhl, 1817) (Chiroptera: Vespertilionidae) is reported for the first time from Poland. The usefulness of some morphological features for differentiating S. bechsteini from other spinturnicid mites belonging to the myoti group was studied. The mite fauna occurring on M. bechsteinii, the only host of S. bechsteini, are very poorly known. In Poland only five species have been found.
Li, Yongqiang; Yang, Na; Wei, Xingcun; Ling, Yun; Yang, Xinling; Wang, Qingmin
Etoxazole, 2-(2,6-difluorophenyl-4-[4-(1,1-dimethylethyl)-2-ethoxy-phenyl]-4,5-dihydrooxazole, an organofluorine chitin synthesis inhibitor, was assayed for its bioactivities against several major insect and acarus pests and compared to several other pesticides: two chitin synthesis inhibitors, hexaflumuron and chlorfluazuron; a pyrethroid, permethrin; an organophosphate, acephate; a carboximide, hexythiazox; and a tetrazine, clofentezine. The LC50 of etoxazole was calculated using probit analysis of the concentration-dependent mortality data against susceptible and resistant strains of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae); diamondback moth, Plutella xylostella L. (Plutellidae); bean aphid, Aphis craccivora Koch (Hemiptera: Aphididae); and carmine spider mite, Tetranychus cinnabarinus (Boisduval) Boudreaux (Trombidiformes: Tetranychidae). The resistant strains were found to be resistant against all tested pesticides except etoxazole. The bioactivity of etoxazole was many times that of the other tested insecticides and acaricides widely used in vegetable crops in China. On the basis of our research, etoxazole can be expected to be extensively used on vegetable crops in China. PMID:25199415
Konecka, Edyta; Olszanowski, Ziemowit
We determined the distribution of microbial endosymbionts as possible agents of parthenogenesis in Oribatida. We screened mites from 20 species of 14 families suspected to be parthenogenetic from the absence or rarity of males. Our research included parthenogenesis-inducing bacteria Wolbachia spp., Cardinium spp., Rickettsia spp., and additionally Arsenophonus, Spiroplasma and microsporidia that can also manipulate host reproduction. We detected the endosymbionts by PCR-based methods and transmission electron microscopy (TEM) observation of fixed and stained preparations of host cells. We detected Wolbachia only in one Oribatida species, Oppiella nova, by identifying Wolbachia genes using PCR. TEM observations confirmed infection by the endosymbiont in O. nova and its lack in other Oribatida species. Sequence analysis of hcpA and fbpA genes showed that the Wolbachia strain from O. nova was different from strains characterized in some insects, crustaceans (Isopoda), mites (Tetranychidae), springtails (Hexapoda) and roundworms (Nematoda). The analysis strongly suggested that the Wolbachia sp. strain found in O. nova did not belong to supergroups A, B, C, D, E, F, H or M. We found that the sequences of Wolbachia from O. nova were clearly distantly related to sequences from the bacteria of the other supergroups. This observation makes O. nova a unique Wolbachia host in terms of the distinction of the strain. The role of these micro-organisms in O. nova remains unknown and is an issue to investigate.
Development and reproduction of Stratiolaelaps scimitus (Acari: Laelapidae) with fungus gnat larvae (Diptera: Sciaridae), potworms (Oligochaeta: Enchytraeidae) or Sancassania aff. sphaerogaster (Acari: Acaridae) as the sole food source.
Cabrera, Ana R; Cloyd, Raymond A; Zaborski, Edmond R
Stratiolaelaps (=Hypoaspis) miles (Berlese) (Acari: Mesostigmata: Laelapidae) is a polyphagous soil-dwelling predatory mite that is widely marketed for use in greenhouse production systems to manage populations of dark-winged fungus gnats, Bradysia spp. (Diptera: Sciaridae) and for supplemental control of thrips. The suggestion by Walter and Campbell (2003, Biol. Control 26: 253-269) that North American commercial cultures of S. miles may actually be S. scimitus was confirmed. The development and reproduction at 21-23 degrees C of S. scimitus provided ad libidum with one of three different prey--the fungus gnat Bradysia aff. coprophila (Lintner), potworms (Enchytraeidae), or Sancassania aff. sphaerogaster (Zachvatkin, 1937) (Acari: Astigmata: Acaridae)--were compared. Developmental duration of the egg and non-feeding larval stages were 2.47 and 1.11 days, respectively; mortalities were 8.3 and 5.5%. Stratiolaelaps scimitus failed to develop beyond the protonymphal stage when provided with S. aff. sphaerogaster alone, although some feeding was observed. Development and reproduction of S. scimitus was successful on both fungus gnat larvae and enchytraeids, with no influence of prey on protonymphal duration (4.70 days) and mortality (8.3%), or on deutonymphal duration (4.61 days) and mortality (6.1%). Adult female S. scimitus feeding on potworms, compared to those feeding on fungus gnat larvae, had a significantly shorter pre-oviposition period (2.69 vs. 4.59 days). However, diet did not influence other adult female developmental or reproductive characteristics (oviposition period, 18.6 days; post-oviposition period, 6.2 days; total adult longevity, 27.3 days; total number of eggs, 26.5). S. scimitus reared on potworms tended (p = 0.06) to have a higher intrinsic rate of increase, a higher finite rate of increase and a shorter doubling time (rm = 0.142 day(-1), lambda = 1.153, Dt = 4.85 days) than those reared on fungus gnat larvae (rm = 0.105 day(-1), lambda = 1
Skoracki, Maciej; Unsoeld, Markus; Kavetska, Katarzyna; Kaszewska, Katarzyna
The paper contains a review of quill mites of the subfamily Picobiinae (Acari: Prostigmata: Syringophilidae) associated with woodpeckers (Aves: Piciformes: Picidae). Three new species are described: Picobia mentalis Skoracki et Unsoeld sp. nov. from Picus mentalis Temminck, Neopicobia ea Skoracki et Unsoeld sp. nov. from Celeus flavus (St. Mueller) (type host), C. elegans (St. Mueller), C. torquatus (Boddaert), and Neopicobia freya Skoracki et Unsoeld sp. nov. from Dryocopus galeatus (Temminck) (type host) and Piculus rubiginosus (Swainson). Additionally, six new host species for Picobia heeri Haller, 1878 and 12 new host species for Picobia dryobatis (Fritsch, 1956) are reported. A complete list of the picobiines parasitising birds of the family Picidae is presented in the tabular form.
Abstract Bark beetles (Scolytinae) are hosts to a broad diversity of mites (Acari), including several genera of Oribatida (Sarcoptiformes). Of these, Paraleius (Scheloribatidae) species are the most frequently collected oribatid mites associated with bark beetles. A new species was discovered while surveying the acarofauna of bark beetles in Eastern Canada and is described as Paraleius leahae sp. n. (Oribatida, Scheloribatidae). This species was collected from two host beetle species, Hylastes porculus Erickson and Dendroctonus valens LeConte, in Ontario, New Brunswick and Nova Scotia. The genus Paraleius is rediagnosed, Metaleius is considered a synonym of Paraleius, and the proposed synonymy of Paraleius with Siculobata is rejected. The three known species are Paraleius leontonycha (Berlese), P. leahae sp. n., and P. strenzkei (Travé), comb. n. The barcode region of cytochrome oxidase subunit I (COI) was amplified from P. leahae sp. n. PMID:28769635
Marques, Sandro; Barros-Battesti, Darci Moraes; Faccini, João Luiz Horacio; Onofrio, Valeria Castilho
Amblyomma varium, commonly known in Brazil as the "carrapato-gigante-da-pregui a" (sloth's giant tick) is found from southern Central America to Argentina. The present study adds information on the geographical distribution of A. varium, as well as on their hosts, based on material deposited in the main Brazilian collections and on the available literature. Eighty-two vials, containing 191 adult specimens, deposited in five Acari collections between 1930 and 2001, were examined. These vials included data on the host and collection localities. The biology of A. varium is unknown. However it is known that, during the adult stage, the tick presents a high host specificity and is found almost exclusively on the sloths Bradypus tridactylus, B. variegatus, B.torquatus (Bradypodidae), Choloepus hoffmanni and C. didactylus (Megalonychidae). Based on the material examined, the states of Rond nia, Amazonas, Bahia and Alagoas are newly assigned to geographic distribution of A. varium in Brazil.
Maestas, Lauren P; Adams, Seryna L; Britten, Hugh B
Ixodes scapularis Say (Acari: Ixodidae) is the most important vector of human disease in the United States. Recent efforts by public health officials to determine its presence on a county-by-county basis have been undertaken to assist in Lyme disease risk assessment. Recent modeling efforts show that South Dakota can potentially support populations of I. scapularis based on favorable climatic conditions and presence of suitable hosts to support tick populations within the state. We provide the first documentation of an established population of I. scapularis in Clay County, SD, providing only the third record of the presence of this tick species within the state. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.
Hartini, Sri; Takaku, Gen
Twelve mite species of the genus Macrocheles (Acari: Macrochelidae) were collected from the body surface of dung beetles in Java, Indonesia. Of these, three species, i.e., Macrocheles jabarensis, M. jonggolensis, and M. sukabumiensis, were described as new to science. Female of M. dispar was redescribed. Two species, i.e., M. baliensis and M. sukaramiensis, were recorded from Java for the first time. The occurrence of five species previously recorded from Java, i.e., M. hallidayi, M. kraepelini, M. limue, M. oigru, and M. merdarius, were reconfirmed. Taxonomic status of M. sp. aff. glaber was not settled in the present study, because we could not obtain the male and immatures which are indispensable for exact identification. In total 15 species of the genus Macrocheles, including 3 species already recorded but not collected in this research (M. crispa, M. krantzi, and M. subbadius), are known from Java up to date.
Mietkiewski, R; Bałazy, S
A new entomopathogenic fungus, described here as Neozygites abacaridis n. sp. (Zygomycetes: Entomophthorales), has been found on the mites Abacarus hystrix, Aculodes dubius, and A. mckenziei (Acari: Eriophyidae). It differs from other Neozygites species affecting mites by its small, globose primary conidia, short-ovoid, smoky coloured capilliconidia, and very short capillary conidiophores-which are usually not longer than the spore length. This pathogen infected mite individuals in autumn (from mid-August until mid-November) on Lolium perenne, Agrostis stolonifera, and Festuca rubra. It caused 0.5-1% host's mortality in the vicinity of Siedlce (Eastern Poland) and up to 2-8%, on an average in Puszczykowo (Wielkopolski National Park near Poznań), where its prevalence on some plants reached 13%.
Mortazavi, Abdolazim; Hajiqanbar, Hamidreza
A new species of mites of the genus Tarsopolipus (Acari: Prostigmata: Podapolipidae) is described from southern Iran. Tarsopolipus husbandi Mortazavi and Hajiqanbar n. sp. is a sub-elytral ectoparasite of the scarabaeid beetle, Scarabaeus (Scarabaeus) acuticollis. The new species is closely related to Tarsopolipus corrugatus Berlese 1911, but is distinguished from it by the following characters. Adult female: presence of vestigial setae v(2) and shorter setae sc(2). Adult male: presence of setae v' on tibia IV and shorter setae sc(2) and c(2). Larval female: shorter cheliceral stylets and longer distance between setae v(1) and ch. Species of Tarsopolipus are currently distributed in Afro-tropical, Palaearctic, and Oriental regions and parasitize species in 3 genera of scarabaeid beetles, i.e., Scarabaeus , Kheper, and Drepanopodes, all belonging to the tribe Scarabaeini.
Rodrigues, J C V; Kitajima, E W; Childers, C C; Chagas, C M
Citrus leprosis is caused by Citrus leprosis virus (CiLV) that is transmitted by mites in the genus Brevipalpus (Acari: Tenuipalpidae). This disease directly reduces production and the life span of the citrus plant. The main symptoms of the disease include lesions on fruits, leaves, and twigs or small branches, causing premature fruit drop, defoliation, and death of the twigs or branches leading to serious tree decline. Leprosis is a highly destructive disease of citrus, wherever it occurs. The Brazilian citrus industry spends over 100 million US dollars annually on acaricides to control the vector, Brevipalpus phoenicis (Geijskes). This review contains information about the history of the etiology of citrus leprosis, its geographical distribution, host range, the role of the mite vectors, viral morphology and relationships with the infected cell, and transmissibility of the virus by the mite. In addition, data on the mite-virus-plant relationship, disease damage, and strategies for controlling disease spread are presented.
Miranda-Miranda, E; Cossio-Bayugar, R; Martínez-Ibañez, F; Casasanero-Orduña, R; Folch-Mallol, J
The purpose of this study was to describe an unreported entomopathogenic fungus that naturally infects the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). Engorged female ticks, showed symptoms of fungal infection after controlled tick infestation of cattle. Infected ticks developed a distinctive dark colour, a pale mould grew over the cuticle and the ticks eventually died covered with fungal conidiophores. The responsible fungus was isolated and cultured on mycological medium and submitted to microscopic morphology, biochemical phenotyping and 18S rRNA ribotyping analyses, which identified it as aflatoxin-producing Aspergillus flavus. Spores from the cultured fungus were experimentally sprayed over healthy engorged female ticks, obtaining an 80% prevalence of experimental infection of healthy ticks and their egg masses, the larval progeny after incubation under laboratory conditions was also infected. These results demonstrate that A. flavus is the causative agent of the natural fungal disease of the cattle tick R. microplus described here.
Venzal, José M; Nava, Santiago; González-Acuña, Daniel; Mangold, Atilio J; Muñoz-Leal, Sebastián; Lado, Paula; Guglielmone, Alberto A
A new species, Ornithodoros microlophi (Acari: Argasidae), belonging to the subgenus Alectorobius is described from larvae collected on the lizards Microlophus atacamensis (Donoso-Barros, 1966) and Microlophus quadrivittatus (Tschudi, 1845) (Squamata: Tropiduridae) in continental and insular localities from northern Chile. Larvae of O. microlophi can be distinguished from other Neotropical species of the genus Ornithodoros by a combination of the following characters, namely 10 pairs of ventral setae, venter with 6 pairs of sternal setae, dorsal plate pyriform, 19-21 pairs of dorsal setae (typically 20), 13 pairs are dorsolateral and 7 pairs are central, and hypostome with dental formula 4/4 in medial portion and apex pointed. Phylogenetic analysis of 16S rDNA sequences suggests that O. microlophi represents an independent lineage within Neotropical species of the Argasidae.
Two-spotted spider mites are important pests in many agricultural systems. Spider mites (Acari: Tetranychidae) have been found to cause economic damage in corn, cotton, and sorghum. Adult glass vial bioassays indicate that Temprano™ (abamectin) is the most toxic technical miticide for adult two-spot...
The twospotted spider mite, Tetranychus urticae (Acari: Tetranychidae), is an important pest of vegetables and other crops. This study was conducted to evaluate and compare the potential role of three commercially available predators, predatory gall midge, Feltiella acarisuga (Vallot) (Diptera: Ceci...
Barbosa, Marina F C; de Moraes, Gilberto J
Laelapidae and Rhodacaridae are important families of edaphic predatory mites and species of these families have been considered for use in biological control programs of soil pests. Mites of Cohort Astigmatina (Acari: Sarcoptiformes) have been largely used as factitious prey in the mass rearing of various edaphic or plant-inhabiting predatory mites. Stratiolaelaps scimitus (Womersley) (Mesostigmata: Laelapidae) (widely commercialized for the control of fungus gnats and thrips) and Protogamasellopsis zaheri Abo-Shnaf, Castilho and Moraes (Mesostigmata: Rhodacaridae) (not available commercially but promising for the control of thrips and nematodes) are known to be reared on Tyrophagus putrescentiae (Schrank) (Astigmatina: Acaridae), but the possibility to find a perhaps more efficient prey has not been evaluated. The objective of this paper was to evaluate different astigmatid species as prey for these predators. S. scimitus and P. zaheri oviposited on all evaluated astigmatids and the acarid mites T. putrescentiae and Aleuroglyphus ovatus (Tropeau) were the most suitable prey; to confirm the effect of prey on oviposition rates, pregnant females of the predators were kept under starvation conditions and oviposition was negligible or null. Survivorship was always higher than 78 % and was not influenced by prey species or starvation.
New species and a record of myrmecophilous mites of the families Neopygmephoridae and Microdispidae (Acari: Heterostigmatina:
Pygmephoroidea) associated with Lasius umbratus (Hymenoptera: Formicidae) from Western Siberia, Russia.
Khaustov, Alexander A
Two new myrmecophilous species of the family Neopygmephoridae (Acari: Pygmephoroidea), Petalomium brevicaudus sp. nov. and P. kurganiensis sp. nov. are described from the ant Lasius umbratus Nylander (Hymenoptera: Formicidae: Formicinae) in Western Siberia, Russia. Another myrmecophilous species of the family Microdispidae (Acari: Pygmephoroidea), Caesarodispus brevipes Mahunka, 1981, was also collected from the ant L. umbratus in Western Siberia, Russia. It is recorded from Russia for the first time and is redescribed in the present paper.
The new eriophyid mite species Aculops dipsaci n. sp. (Acari: Prostigmata: Eriophyidae) collected from Dipsacus laciniatus L. (Dipsacaceae) in northern Serbia is described and illustrated. Differential diagnosis is provided in comparison with Aculops salixis Xue, Song and Hong. This is the first e...
Khaustov, Alexander A
A new species of the genus Paravillersia Kuznetsov, 1978 (Acari: Stigmaeidae), P. jamaliensis Khaustov sp. nov. is described from mosses on fen in Western Siberia, Russia. The supplementary description of Paravillersia grata Kuznetsov, 1978 is provided based on the type material.
Vatankhah, Farzaneh; Nemati, Alireza; Esfandiari, Mehdi; Shishehbor, Parviz
A new species of Gaeolaelaps (Acari, Mesostigmata, Laelapidae) is described based on morphological characters of adult females collected from nest of Formica sp. (Hymenoptera: Formicidae) in the Shahrekord Region, Chaharmahal va Bakhtiari province, Iran. A key for the identification of species of Gaeolaelaps with short peritremes is presented.
Noei, Javad; Saboori, Alireza; Hajizadeh, Jalil
Diplothrombium sahragardi sp. nov. and Diplothrombium ostovani sp. nov. (Acari: Johnstonianidae) collected from soil samples (off host) in a forest near Asalem city (Iran) are described. Another species of this family Johnstoniana parva Wendt, Wohltmann, Eggers and Otto, 1994 is reported for the first time from Iran. A larva-based key to Diplothrombium is provided.
Tom W. Coleman; Michael I. Jones; Mark S. Hoddle; Laurel J. Haavik; John C. Moser; Mary L. Flint; Steven J. Seybold
The straw itch mite, Pyemotes tritici LagrÃ¨ze-Fossat andMontanÃ© (Acari: Pyemotidae), was discovered parasitising the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), an invasive exotic species to California, United States of America, and the Mexican goldspotted oak borer, Agrilus coxalis Waterhouse (Coleoptera:...
Pešić, Vladimir; Semenchenko, Ksenia
In this study, four water mites of the genus Brachypoda (Acari: Hydrachnidia: Aturidae) are reported from South Korea and the Far East of Russia. Brachypoda (Ocybrachypoda) milicaae sp. n. (South Korea), B. (Ocybrachypoda) sokolowi sp. n. (Russia) and B. (Eubrachypoda) rossica sp. n. (Russia) are described as new for science. The latter species is the second representative of the subgenus Eubrachypoda Tuzovskij, 2004, previously known only from Lake Biwa in Japan. A new record of Brachypoda rubidata Kim & Chung, 1996, a species so far known only from a pond in Bosung (South Korea), is given.
Menon, Pratibha; Joshi, Sushila; Ramamurthy, Vilayanoor Venkataraman
A new species of Eriophyidae (Acari: Prostigmata: E riophyoidea) mite, Aceria tripuraensis n. sp., is described from the closed bud galls of Hibiscus macrophyllus Roxb. ex Hornem. (Malvaceae) in India. Aceria tripuraensis n. sp. is distinguished by having a prodorsal shield with distinct rounded lobes on the postero-lateral margins and two pairs of submedian lines. The tarsal solenidia with unusual transverse sculptures, are 2.5x longer than the empodia. Twenty Aceria species are now known to inhabit malvaceous plant hosts and those are listed here along with type localities and host plant details. A key to all known species of Aceria recorded from Hibiscus spp. is also provided.
Loghmani, Amir; Hajiqanbar, Hamidreza; Talebi, Ali Asghar
Pavania setiformis Loghmani & Hajiqanbar sp. nov. (Acari: Heterostigmatina: Dolichocybidae) associated with Onthophagus (Palaeonthophagus) vitulus (Fabricius) (Coleoptera: Scarabaeidae) is described from northeastern Iran. This remarkable new species represents a new setiformis species group characterized by seta-like sc(1), instead of capitate trichobothria. The genus Pavania is thus divided into three species groups: the fusiformis group (15 species), the gymnopleuri group (3 species) and the setiformis group (1 species). We also found P. sabzevarensis Hajiqanbar & Khaustov, 2010 and P. onthophagi Hajiqanbar & Khaustov, 2010 phoretic on Gymnopleurus mopsus (Pallas) and Onthophagus (Euonthophagus) amyntas alces (Fabricius), respectively.
Maegli, Amanda; Loy, J Dustin; Cortinas, Roberto
The lone star tick, Amblyomma americanum (L.) (Acari: Ixodidae), is established in southeastern Nebraska yet the prevalence of tick-associated microorganisms is not known. An initial PCR-based analysis for Ehrlichia chaffeensis, Ehrlichia ewingii, and Borrelia infection in host-seeking adult ticks collected in southeast Nebraska was conducted. A total of 251 adult ticks collected in six sites in southeast Nebraska were tested. E. chaffeensis, E. ewingii, and Borrelia spp. were present, and the prevalence of each was approximately 1.6%. This study demonstrates that Ehrlichia spp. are present in Nebraska lone star tick populations.
Koc, Samed; Oz, Emre; Aydın, Levent; Cetin, Huseyin
Acaricidal effects of three Labiatae essential oils extracted from ariel parts of Thymus sipyleus Boiss. subsp. sipyleus, Mentha longifolia L., and Dorystoechas hastata Boiss. & Heldr. ex Bentham on 10-day-old Rhipicephalus turanicus Pom. (Acari: Ixodidae) larvae were evaluated by using the larval packet test bioassay. Serial dilutions of the three essential oils were tested from a starting concentration of 1-0.1% (1.0, 0.5, 0.25, and 0.1% w/v). Results showed that all essential oils had very similar activity, producing complete mortality (100%) in all tested concentrations on 10-day-old R. turanicus tick larvae.
Sobhi, Mohammad; Hajiqanbar, Hamidreza; Mortazavi, Abdolazim
A species of mites of the genus Eutarsopolipus Berlese, 1911 (Acari: Prostigmata: Podapolipidae), Eutarsopolipus elongatus Regenfuss, 1968, belonging to the acanthomus species group, is found from northwestern Iran. This is first record of the species from Asia including Iran. Also, unknown male of this species is discovered. During a survey on mites associated with insects in northwestern Iran, three colonies of this ectoparasitic species were recovered from subelytral cavity of the carabid beetles (Amara aenea). Purposes of this article are to describe the male and to redescribe the larval and adult females of this species, with world key to male stage of the acanthomus species group of the genus Eutarsopolipus.
Bashir, Muhammad Hamid; Afzal, Muhammad; Ashfaq, Muhammad; Ali, Shaukat; Kamran, Muhammad; Honey, Sabyan Faris
The Coleoscirinae (Acari: Trombidiformes: Cunaxidae) from Pakistan are summarized in this paper. Two species of Scutascirus Den Heyer (S. pirgus Chaudhri and Akbar and S. tactus Chaudhri and Akbar), ten species of Coleoscirus Berlese (C. baptos (Chaudhri and Akbar), C. carex (Inayatullah and Shahid), C. carnus Muhammad and Chaudhri, C. comis Muhammad and Chaudhri, C. disparis Muhammad and Chaudhri, C. irroratus Muhammad and Chaudhri, C. mardi (Inatullah and Shahid), C. raviensis Afzal, Ashfaq and Khan, C. tobaensis Bashir, Afzal, Ashfaq, and Khan, and C. trudus Bashir, Afzal and Akbar), and three species of Pseudobonzia Smiley (P. ashfaqi Bashir, Afzal and Akbar, P. numida Chaudhri and Akbar, and P. parilus Chaudhri) have been previously reported. One new species of Pseudobonzia, Pseudobonzia bakeri sp. n., is herein described and illustrated. A key to the genera of the subfamily and keys to the species in each genus are given to incorporate the new species from Pakistan. Distribution records of all known species in Pakistan are also given. PMID:25368038
Monteiro, Vaneska B; Lima, Debora B; Gondim, Manoel G C; Siqueira, Herbert A A
Aceria guerreronis Keifer (Acari: Eriophyidae) is considered a major pest of the coconut (Cocos nucifera L.), and the use of pesticides is the current method to control it. However, no standard toxicological tests exist to select and assess the efficiency of molecules against the coconut mite. The aim of this study was to develop a methodology that allows for the evaluation of the relative toxicity of acaricides to A. guerreronis through rapid laboratory procedures. We confined A. guerreronis on arenas made out of coconut leaflets and tested two application methods: immersing the leaf fragments in acaricides and spraying acaricides on the leaf fragments under a Potter spray tower. In the latter application method, we sprayed leaf fragments both populated with and devoid of mites. We evaluated the comparative toxicity of two populations (Itamaracá and Petrolina, Pernambuco, Brazil) by spraying on leaflets without mites and submitted the mortality data to probit analysis after 24 h of exposure. No difference was observed in the LC50, regardless of whether the leaflets were immersed or sprayed with acaricide (abamectin, chlorfenapyr or fenpyroximate). The toxicity of chlorfenapyr and fenpyroximate did not differ, irrespective of whether it was applied directly to the leaflet or to the mite; however, the toxicity of abamectin was higher when applied directly to the mite. Chlorpyrifos and abamectin toxicities were lower for the Petrolina population than for the Itamaracá population. Immersing and spraying coconut leaflets can be used to assess the mortality of A. guerreronis under laboratory conditions.
Rulison, Eric L.; Kuczaj, Isis; Pang, Genevieve; Hickling, Graham J.; Tsao, Jean I.; Ginsberg, Howard S.
The nymphal stage of the blacklegged tick, Ixodes scapularis (Acari: Ixodidae), is responsible for most transmission of Borrelia burgdorferi, the etiologic agent of Lyme disease, to humans in North America. From 2010 to fall of 2012, we compared two commonly used techniques, flagging and dragging, as sampling methods for nymphal I. scapularis at three sites, each with multiple sampling arrays (grids), in the eastern and central United States. Flagging and dragging collected comparable numbers of nymphs, with no consistent differences between methods. Dragging collected more nymphs than flagging in some samples, but these differences were not consistent among sites or sampling years. The ratio of nymphs collected by flagging vs dragging was not significantly related to shrub density, so habitat type did not have a strong effect on the relative efficacy of these methods. Therefore, although dragging collected more ticks in a few cases, the numbers collected by each method were so variable that neither technique had a clear advantage for sampling nymphal I. scapularis.
El-Seedi, Hesham R; Azeem, Muhammad; Khalil, Nasr S; Sakr, Hanem H; Khalifa, Shaden A M; Awang, Khalijah; Saeed, Aamer; Farag, Mohamed A; AlAjmi, Mohamed F; Pålsson, Katinka; Borg-Karlson, Anna-Karin
Due to the role of Ixodes ricinus (L.) (Acari: Ixodidae) in the transmission of many serious pathogens, personal protection against bites of this tick is essential. In the present study the essential oils from 11 aromatic Egyptian plants were isolated and their repellent activity against I. ricinus nymphs was evaluated Three oils (i.e. Conyza dioscoridis L., Artemisia herba-alba Asso and Calendula officinalis L.) elicited high repellent activity in vitro of 94, 84.2 and 82%, respectively. The most active essential oil (C. dioscoridis) was applied in the field at a concentration of 6.5 µg/cm(2) and elicited a significant repellent activity against I. ricinus nymphs by 61.1%. The most repellent plants C. dioscoridis, C. officinalis and A. herba-alba yielded essential oils by 0.17, 0.11 and 0.14%, respectively. These oils were further investigated using gas chromatography-mass spectrometry analysis. α-Cadinol (10.7%) and hexadecanoic acid (10.5%) were the major components of C. dioscoridis whereas in C. officinalis, α-cadinol (21.2%) and carvone (18.2%) were major components. Artemisia herba-alba contained piperitone (26.5%), ethyl cinnamate (9.5%), camphor (7.7%) and hexadecanoic acid (6.9%). Essential oils of these three plants have a potential to be used for personal protection against tick bites.
Skoracki, Maciej; Hromada, Martin
A fauna of quill mites of the subfamily Picobiinae (Acari: Syringophilidae) associated with African birds is revised. Two new monotypic genera are proposed, Gunabopicobia gen. n. for Picobia zumpti Lawrence, 1959 and Lawrencipicobia gen. n. for Picobia poicephali Skoracki et Dabert, 2002. These new genera differ from other genera of the subfamily by the following features: in females of Gunabopicobia, propodonotal setae vi are situated anterior to the level of setae ve; the narrow lateral propodonotal shields bear bases of setae vi, ve, si and se; the bases of setae 1a-1a are coalesced; the genital setae and the opisthosomal lobes are absent; the leg I with full set of solenidia and apodemes I are devoid of the thorn-like protuberances in the middle part. In females of Lawrencipicobia, the bases of setae 1a-1a are not coalesced; the propodonotal shield is entire; the genital setae are present; legs I are with full set of solenidia. Additionally, two new species belonging to Picobia Haller, 1878 are described, Picobia illadopsae sp. n. parasitising Illadopsis rufipennis (Sharpe) (Passeriformes: Pellorneidae) in Kenya and Picobia phoenicuri sp. n. infecting Phoenicurus moussieri (Olphe-Galliard) in Tunisia. The following species are redescribed, Columbiphilus alectoris (Fain, Bochkov et Mironov, 2000), Lawrencipicobia poicephali (Skoracki et Dabert, 2001) comb. n. and Picobia phoeniculi (Fain, Bochkov et Mironov, 2000). The key to the genera of the Picobiinae is provided.
Allan, Brian F
The increasingly widespread use of prescribed burns to manage oak (Quercus spp.)-hickory (Carya spp.) forests in the Missouri Ozarks, USA, has considerable potential to alter the abundance of Amblyomma americanum (L.) (Acari: Ixodidae), the lone star tick, an important vector of several emerging pathogens. In particular, responses of important tick hosts, primarily white-tailed deer (Odocoileus virginianus), to fire management and the resultant changes in the distribution and abundance of A. americanum are largely unknown. Using several large burn units (61-242 ha) within the Ozark ecosystem, I measured the effect of the time elapsed since sites were burned on the density of white-tailed deer and the larval life stage of A. americanum. Larval tick densities were highest in areas that were 2 yr postburn and were > 6 times higher than tick densities in control units. Deer densities were highest in sites that were burned in the same year as this study and decreased significantly with time since burn. These results suggest that intensive use of postburn sites by white-tailed deer may increase the abundance of A. americanum to levels greater than occurs in sites that remain unburned. Thus, fire management, although beneficial in many aspects of ecosystem management, may bear the unintended cost of locally increasing abundance of A. americanum.
In the alpine region at Finse, Norway, Phauloppia spp. (Acari, Oribatida) inhabit lichens on top of boulders. Adult mites are about 0.5 mm in length and have a mean weight of ca. 15 µg. Temperatures in the lichens may drop below -35 degrees C in winter and increase to 55 degrees C in the summer. Large seasonal variations were recorded in supercooling points and body fluid osmolality. Mean January values of SCPs and osmolality were -35.3 degrees C and 3756 mOsm, while July values were -9.4 degrees C and 940 mOsm, respectively. Thermal hysteresis proteins were present in both summer and winter acclimated mites. In mid-winter, some of the mites survived more than 49 days in a water vapor saturated atmosphere at -19 degrees C, and more than 42 days enclosed in ice at the same temperature.The mites showed high tolerance to desiccation. Specimens collected in October survived up to 23 days at 22 degrees C and 5% RH. The tolerance to desiccation was lower in specimens collected during the winter. Some mites survived the loss of up to 90% of their total water content and were reactivated when given access to water. Length measurements of individual Phauloppia sp. showed that both male and female mites are clearly divided in two size groups, suggesting that they belong to two closely related species or different populations.
Lee, K V; Moon, R D; Burkness, E C; Hutchison, W D; Spivak, M
The parasitic mite Varroa destructor Anderson & Trueman (Acari: Varroidae) is arguably the most detrimental pest of the European-derived honey bee, Apis mellifera L. Unfortunately, beekeepers lack a standardized sampling plan to make informed treatment decisions. Based on data from 31 commercial apiaries, we developed sampling plans for use by beekeepers and researchers to estimate the density of mites in individual colonies or whole apiaries. Beekeepers can estimate a colony's mite density with chosen level of precision by dislodging mites from approximately to 300 adult bees taken from one brood box frame in the colony, and they can extrapolate to mite density on a colony's adults and pupae combined by doubling the number of mites on adults. For sampling whole apiaries, beekeepers can repeat the process in each of n = 8 colonies, regardless of apiary size. Researchers desiring greater precision can estimate mite density in an individual colony by examining three, 300-bee sample units. Extrapolation to density on adults and pupae may require independent estimates of numbers of adults, of pupae, and of their respective mite densities. Researchers can estimate apiary-level mite density by taking one 300-bee sample unit per colony, but should do so from a variable number of colonies, depending on apiary size. These practical sampling plans will allow beekeepers and researchers to quantify mite infestation levels and enhance understanding and management of V. destructor.
Ernieenor, F C L; Ernna, G; Mariana, A
Morphotaxonomy based on phenotypic traits of immature hard ticks (Acari: Ixodidae) is a skill challenge and has prompted many inexperienced acarologists to adopt DNA-based methods for identifying and discriminating the species. The aim of this study is therefore to utilize COI gene for verifying the morphological status of Haemaphysalis ticks in Peninsular Malaysia. A total of 19 on-host ticks collected from four localities were first identified using specific illustrated taxonomic keys that lead to the genus of Haemaphysalis. Genotypic traits of tick species were then verified molecularly based on cytochrome oxidase subunit I (COI) gene using polymerase chain reaction and direct sequencing. Clustering analysis was carried out by constructing a phylogenetic tree to determine the genetic variation and diversity of local Haemaphysalis ticks. Based on external morphological characterizations, all immature ticks were successfully identified down to the genus level only. Molecular analysis of the genotypic using COI gene revealed 16 individuals (84%) as Haemaphysalis hystricis, and three individuals as H. humerosa with sequence homology of 97-99 and 86-87%, respectively. Haemaphysalis hystricis were clustered in their respective monophyletic group in the phylogeny trees with a bootstrap of 100%. Furthermore, a low intraspecific variation (<0.3%) was observed among Malaysian H. hystricis but high interspecific value (>15%) recorded. This study morphologically and molecularly confirms the presence of H. hystricis in Malaysia and the findings will add value to the existing knowledge in identification of ticks in this country.
Mays, S E; Houston, A E; Trout Fryxell, R T
Amblyomma maculatum Koch (Acari: Ixodidae) is established in western Tennessee, a region with increased risk for Rocky Mountain spotted fever and ehrlichiosis. This tick transmits Rickettsia parkeri to humans, likely contributing to cases of rickettsiosis in the region. The objective was to determine pathogen associations within questing and host-collected A. maculatum, and identify ecological factors associated with pathogen infection that may increase the effectiveness of surveillance methods. Of 265 ticks tested, 60 (22.6%) were infected with R. parkeri, and 15 (5.7%) with Candidatus Rickettsia andeanae, a Rickettsia of unknown pathogenicity. Two deer-collected ticks tested positive for Ehrlichia ewingii. No ticks were positive for Anaplasma or Borrelia species. None of the ecological factors tested (collection month, collection source, sex, and habitat type) were associated with R. parkeri infection. This project developed baseline prevalence and incidence data for monitoring pathogen prevalence in A. maculatum populations, and identified an inexpensive method for distinguishing R. parkeri from Ca. R. andeanae.
Hope, Michelle; Menzies, Moira; Kemp, David
The southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae), is a major vector of tick fever organisms affecting cattle in many parts of the world, including Australia, Africa, and South America. Control of the southern cattle tick through acaricide use is an important approach in disease management. Resistance has emerged to many of the acaricides currently and previously used, including the cyclodienes. Although cyclodiene resistance mechanisms have been characterized in many insect species, this report is the first to identify mutations associated with dieldrin resistance in the cattle tick. A novel two base pair mutation in the GABA-gated chloride channel gene has been identified at position 868-9 and causes a codon change from threonine to leucine. Analysis of a small number of field-collected samples resistant to dieldrin shows this mutation has been maintained without selection pressure since the withdrawal of dieldrin in Australia > 20 yr ago. The mutation is not found in other laboratory-maintained strains of R. microplus that were subject to selection pressure with various acaricides.
Sammataro, D; Finley, J; Underwood, R
The effectiveness of oxalic acid (OA) and Sucrocide (S) (AVA Chemical Ventures, L.L.C., Portsmouth, NH) in reducing populations of the varroa mite Varroa destructor Anderson & Trueman (Acari: Varroidae) in honey bee, Apis mellifera L. (Hymenoptera: Apidae) colonies was measured under the desert conditions of Arizona, USA. OA and S were applied three times 7 d apart. A 3.2% solution of OA was applied in sugar syrup via a large volume syringe, trickling 5 ml per space between frames in the colony. S was applied at a concentration of 0.625% (mixed with water), according to the label directions, using a compressed air Chapin sprayer at 20 psi to apply 59 ml per frame space. Varroa mites, collected on a sticky board before, during, and after the treatments, were counted to assess the effectiveness of the treatments. This study showed that a desert climate zone did not confer any positive or negative results on the acaricidal properties of OA. Even with brood present in colonies, significant varroa mite mortality occurred in the OA colonies. In contrast, we found that Sucrocide was not effective as a mite control technique. Despite its ability to increase mite mortality in the short-term, varroa mite populations measured posttreatment were not affected any more by Sucrocide than by no treatment at all.
Oliveira, D C; de Moraes, G J; Dias, C T S
The coconut mite, Aceria guerreronis Keifer, is one of the main pests of coconut palms (Cocos nucifera) in northeastern Brazil. The objective of this study was to evaluate the levels of the coconut mite and other mites on coconut palms in the state of São Paulo and to estimate the possible role of predatory mites in the control of this pest. The effect of cultivated genotypes and sampling dates on the mite populations was also estimated. We sampled attached fruits, leaflets, inflorescences, and fallen fruits. The coconut mite was the main phytophagous mite found on attached and fallen fruits, with average densities of 110.0 and 20.5 mites per fruit, respectively. The prevalent predatory mites on attached and fallen fruits were Proctolaelaps bulbosus Moraes, Reis & Gondim Jr. and Proctolaelaps bickleyi (Bram), both Melicharidae. On leaflets, the tenuipalpids Brevipalpus phoenicis (Geijsks) and Tenuipalpus coyacus De Leon and the tetranychid Oligonychus modestus (Banks) were the predominant phytophagous mites. On both leaflets and inflorescences, the predominant predatory mites belonged to the Phytoseiidae. Neoseiulus baraki (Athias-Henriot) and Neoseiulus paspalivorus (De Leon), predators widely associated with the coconut mite in northeastern Brazil and several other countries, were not found. The low densities of the coconut mite in São Paulo could be related to prevailing climatic conditions, scarcity of coconut plantations (hampering the dispersion of the coconut mite between fields), and to the fact that some of the genotypes cultivated in the region are unfavorable for its development.
Horn, Tamara Bianca; Körbes, Júlia Horn; Granich, Juliana; Senter, Malena; Ferla, Noeli Juarez
Intensive production of confined laying hens affects their welfare and increases the risk of epidemics. Ectoparasites as hematophagous and feather mites cause low productivity and decreased egg quality. This study aimed to determine the diversity of mites captured with traps in different commercial systems of laying hens (Gallus gallus L.) (Phasianidae) in Taquari Valley, Rio Grande do Sul, Brazil. Samplings were conducted from August 2013 to August 2014, totaling 21 sampling events in three different commercial laying hen systems: automatic production systems (A(1), (2), (3)), semiautomatic systems (S(1), (2)), and free-range system (FR). A total of 9981 mites belonging to 21 families, 31 genera, and 35 species were found. Acaridae, Caligonellidae, and Cheyletidae showed the highest richness with four species each. Megninia ginglymura (Mégnin, 1877) (Analgidae) was the most abundant ectoparasite species with 1328 specimens and was present in all commercial laying hen systems. No hematophagous mites were found. Cheyletus malaccensis(Cheyletidae) (3503), Typhlodromus transvaalensis (Phytoseiidae) (304), and Blattisocius keegani (Blattisocidae) (181) were the predators present in all systems. The similarity with control system (S(1)--without pesticide) was low (36.5 %) when compared to all other commercial laying hen systems, and it had the highest richness. In FR, low populations of mites and highest diversity were observed. The commercial laying hen system and the management influence the mite fauna in poultry farms.
Goessling, Lisa S; Allan, Brian F; Mandelbaum, Rachel S; Thach, Robert E
Unique oligonucleotide probes were synthesized to distinguish among closely related vertebrate mitochondrial rDNA sequences present in residual bloodmeals in emergent Amblyomma americanum (L.) (Acari: Ixodidae) nymph life-stage ticks. Use of these probes enabled the identification of the Eastern gray squirrel as an important bloodmeal source in nymphs harboring Ehrlichia and Borrelia species. These results were confirmed by identifying these same bacterial genera in Eastern gray squirrel tissues.
Phylogenetic Analysis of the Spider Mite Sub-Family Tetranychinae (Acari: Tetranychidae) Based on the Mitochondrial COI Gene and the 18S and the 5′ End of the 28S rRNA Genes Indicates That Several Genera Are Polyphyletic
Matsuda, Tomoko; Morishita, Maiko; Hinomoto, Norihide; Gotoh, Tetsuo
The spider mite sub-family Tetranychinae includes many agricultural pests. The internal transcribed spacer (ITS) region of nuclear ribosomal RNA genes and the cytochrome c oxidase subunit I (COI) gene of mitochondrial DNA have been used for species identification and phylogenetic reconstruction within the sub-family Tetranychinae, although they have not always been successful. The 18S and 28S rRNA genes should be more suitable for resolving higher levels of phylogeny, such as tribes or genera of Tetranychinae because these genes evolve more slowly and are made up of conserved regions and divergent domains. Therefore, we used both the 18S (1,825–1,901 bp) and 28S (the 5′ end of 646–743 bp) rRNA genes to infer phylogenetic relationships within the sub-family Tetranychinae with a focus on the tribe Tetranychini. Then, we compared the phylogenetic tree of the 18S and 28S genes with that of the mitochondrial COI gene (618 bp). As observed in previous studies, our phylogeny based on the COI gene was not resolved because of the low bootstrap values for most nodes of the tree. On the other hand, our phylogenetic tree of the 18S and 28S genes revealed several well-supported clades within the sub-family Tetranychinae. The 18S and 28S phylogenetic trees suggest that the tribes Bryobiini, Petrobiini and Eurytetranychini are monophyletic and that the tribe Tetranychini is polyphyletic. At the genus level, six genera for which more than two species were sampled appear to be monophyletic, while four genera (Oligonychus, Tetranychus, Schizotetranychus and Eotetranychus) appear to be polyphyletic. The topology presented here does not fully agree with the current morphology-based taxonomy, so that the diagnostic morphological characters of Tetranychinae need to be reconsidered. PMID:25289639
McCoy, Brandi N.; Raffel, Sandra J.; Lopez, Job E.; Schwan, Tom G.
Ornithodoros hermsi Wheeler (Acari: Argasidae) is the vector of Borrelia hermsii, the primary cause of tick-borne relapsing fever in North America. This tick is one of the smallest Ornithodoros species involved with the biological transmission of spirochetes; yet, the amount of blood ingested while feeding is unknown. Therefore, we determined the amount of blood O. hermsi ingested during a bloodmeal to establish its potential for spirochete acquisition while feeding on an infected host. Ticks at different developmental stages were weighed before and after feeding and the volume of blood ingested was calculated. Females ingested the most blood, averaging ≈15 µl per meal, but late-stage nymphs took in the most blood in proportion to unfed body weight. A cohort of nymphs was weighed three more times during the 48 h after feeding, which demonstrated that O. hermsi may have excreted coxal fluid ranging from 24 –36% of the bloodmeal weight. We also developed a quantitative polymerase chain reaction method to determine the number of spirochetes ingested and maintained within the ticks after feeding. The density of spirochetes in ticks having just engorged was slightly less than in the host’s blood. In the first 5 d after feeding, the number of spirochetes within the ticks declined from the number initially ingested but then remained constant through 15 d. These observations establish a basis for future studies to determine the minimum number of spirochetes required in the host’s blood to allow O. hermsi to become persistently infected and transmit during subsequent bloodmeals. PMID:21175068
Amoah, Barbara; Schilling, M W; Phillips, Thomas W
Methyl bromide is the most effective fumigant for controlling the mold (or ham) mite, Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), the most significant pest of dry-cured ham. However, methyl bromide is being phased out of use. Therefore, integrated pest management (IPM) methods should be developed to help control mites in dry-cured ham plants. The foundation of a successful IPM program is an effective monitoring program that provides information on pest presence and abundance over time. By using food-baited traps fabricated from disposable petri dishes and a dog food-based bait, mite activity over time and space was monitored in five dry-cured ham aging rooms from three commercial processing facilities that differed in their fumigation frequencies. Weekly sampling of the mite was conducted from June 2012 to September 2013. There were significant differences in the average weekly trap captures in all facilities, especially before and after fumigation, with the majority of mites in traps prior to fumigation. Mite numbers had a pattern of sharp decline after fumigation, followed by a steady increase until the next fumigation. Average trap captures varied due to trap location over the study period at all study sites, indicating that traps could be used to identify specific locations within an aging room where mite infestation of hams was more likely to occur. These findings can inform facility managers of mite population changes that can be used as one factor toward making pest management decisions and assessing the impact of fumigation or other pest mitigation actions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Greay, Telleasha L; Oskam, Charlotte L; Gofton, Alexander W; Rees, Robert L; Ryan, Una M; Irwin, Peter J
Ticks are among the most important vectors of pathogens affecting companion animals, and also cause health problems such as tick paralysis, anaemia, dermatitis, and secondary infections. Twenty ixodid species have previously been recorded on dogs, cats, and horses in Australia, including Rhipicephalus sanguineus, Ixodes holocyclus and Haemaphysalis longicornis, which transmit tick-borne diseases. A survey of hard ticks (Acari: Ixodidae) was conducted during 2012-2015 to investigate tick species that infest dogs, cats, and horses in Australia. Individual tick specimens were collected from dogs, cats and horses across Australia and sample collection locations were mapped using QGIS software. Ticks were morphologically examined to determine species, instar and sex. The companion animal owners responded to questionnaires and data collected were summarised with SPSS software. A total of 4765 individual ticks were identified in this study from 7/8 states and territories in Australia. Overall, 220 larvae, 805 nymphs, 1404 males, and 2336 females of 11 tick species were identified from 837 companion animal hosts. One novel host record was obtained during this study for Ixodes myrmecobii, which was found on Felis catus (domestic cat) in the town of Esperance, Western Australia. The most common tick species identified included R. sanguineus on dogs (73 %), I. holocyclus on cats (81 %) and H. longicornis on horses (60 %). This study is the first of its kind to be conducted in Australia and our results contribute to the understanding of the species and distribution of ticks that parasitise dogs, cats, and horses in Australia. Records of R. sanguineus outside of the recorded distribution range emphasise the need for a systematic study of the habitat range of this species. Several incomplete descriptions of ixodid species encountered in this study hindered morphological identification.
Kitajima, E W; Rezende, J A M; Rodrigues, J C V
Passion fruit green spot disease was first identified in 1997 after a severe outbreak at Vera Cruz County, state of São Paulo, Brazil. Mature yellow fruits of Passiflora edulis Simms f. flavicarpa Degener showed characteristic green spots, 2-5 mm in diameter and patches of green tissues were present on senescent leaves. The devastating effect to passion flower is caused by necrotic lesions that encircle the stems and kill the plant. In severe cases, entire orchards of a few hectares in size have been completely destroyed. The disease was always preceded by heavy infestations of Brevipalpus phoenicis (Geijskes) (Acari: Tenuipalpidae). Transmission electron microscopy of affected tissues (fruits, leaves, and stems) consistently revealed the presence of short, bacilliform particles (50-70 nm x 100-120 nm) in the cisternae of the endoplasmic reticulum, as well as the presence of a dense viroplasm in the cytoplasm. This cytopathic effect has been found in several other Brevipalpus-transmitted or associated viruses and is classified as a cytoplasmic type of disease. Experimental reproduction of the leaf and stem symptoms was achieved by transferring B. phoenicis collected from affected field passion flower plants onto healthy plants. The evidence supports a viral etiology for the disease and the agent was named passion fruit green spot virus. Its relationship with other B. phoenicis related viruses continues to be studied. The disease was also found in the Brazilian states of Bahia, Sergipe, Rondonia, Minas Gerais, Rio de Janeiro, and in the Federal District. Use of one or more of the following acaricides (hexythiazox, fenbutatin-oxide, propargite, quinomethionate, or dicofol) has significantly reduced the incidence of the disease.
Mixson, T.R.; Campbell, S.R.; Gill, J.S.; Ginsberg, H.S.; Reichard, M.V.; Schultz, T.L.; Dasch, G.A.
Ambyomma antericanum (L.) (Acari: Ixodidae) is an aggressive tick that feeds on humans during all postembryonic life stages. In many regions of the United States, it is the tick most commonly found attached to humans. Public health interest has grown recently, due to the recognition of new human pathogens transmitted by A. antericanum and the expanding distribution of the tick. A. americanum is a vector of several bacteria pathogenic to humans. Ehrlichia chaffeensis and Ehrlichia ewingii cause moderate-to-severe febrile illness. 'Rickettsia amblyommii,' a member of the spotted fever group Rickettsia, also has recently been implicated as a possible human pathogen based on serologic evidence from persons recovering from illness after a tick bite. We have determined the prevalence of infection of Ehrlichia chaffeensis, E. ewingii, 'Borrelia lonestari,' and R. amblyommii within A. americanum ticks from 29 sites in nine states. Overall infection prevalences were 4.7% for E. chaffeensis (range, 0-27%), 3.5% for E. ewingii (range, 0-18.6%), 2.5% for B. lonestari (range, 0-12.2%), and 41.2% for R. amblyommii (range, 0-84.0%). In addition, 87 ticks (4.3%) were infected with two or more bacteria. This report documents new distribution records for E. ewingii, B. lonestari, and R. amblyommii and underscores the nonhomogeneous distribution of pathogen foci of infection. Additional surveillance throughout the range of A. antericanum is warranted to increase physician and public awareness of the risk of disease to humans from exposure to the agents transmitted by this tick.
Lohmeyer, K H; Miller, J A; Pound, J M; Oehler, D D
Steers were treated with doramectin or eprinomectin by daily oral capsule for 28 consecutive days. The level of doramectin in the serum of steers treated at 200 microg/kg/d reached a maximum of 104.0 +/- 22.1 ppb at day 21 and declined from 93.3 +/- 20.5 ppb on the final day of treatment to below detectable by day 56. Steers treated at 50 microg/kg/d reached a maximum level of doramectin in the serum of 24.7 +/- 1.2 ppb on day 21 and declined from 24.7 +/- 0.6 ppb on the final day of treatment to less than detectable on day 42. Both doramectin dosages provided 100% control of estimated larvae (EL) of Amblyomma americanum (L.) (Acari: Ixodidae) throughout the 28-d treatment period. Daily oral treatment with eprinomectin at a dosage of 200 microg/kg for 28 consecutive days produced a maximum concentration in the serum of 41.6 +/- 11.0 ppb at day 14. On the final day of eprinomectin treatment, the serum concentration was 38.3 +/- 5.9 ppb. Seven days later at day 35, eprinomectin was not detectable in the serum. For steers treated at 50 microg/kg/d for 28 consecutive days, the serum level of eprinomectin reached a maximum of 10.0 +/- 3.0 ppb on day 28 and was undetectable on day 35. Both eprinomectin dosages provided complete control of EL of A. americanum during the 28-d treatment period. Because eprinomectin is efficacious against A. americanum at lower serum levels in cattle and is eliminated from the serum at a more rapid rate than either doramectin or ivermectin, it provides advantages for use in applications such as the medicated bait for control of ticks on white-tailed deer and could have potential for use in the Cattle Fever Tick Eradication Program.
Heise, Stephanie R; Elshahed, M S; Little, S E
The lone star tick, Amblyomma americanum (Acari: Ixodidae), is commonly reported from people and animals throughout the eastern U.S. and is associated with transmission of a number of emerging diseases. To better define the microbial communities within lone star ticks, 16S rRNA gene based analysis using bacteria-wide primers, followed by sequencing of individual clones (n = 449) was used to identify the most common bacterial operational taxonomic units (OTUs) present within colony-reared and wild A. americanum. The colony-reared ticks contained primarily sequence affiliated with members of the genus Coxiella (89%; 81/91), common endosymbionts of ticks, and Brevibacterium (11%; 10/91). Similarly, analysis of clones from unfed wild lone star ticks revealed that 96.7% (89/92) of all the OTUs identified were affiliated with Coxiella-like endosymbionts, as compared with only 5.1-11.7% (5/98-9/77) of those identified from wild lone star ticks after feeding. In contrast, the proportion of OTUs identified as Rickettsia sp. in wild-caught ticks increased from 2.2% (2/92) before feeding to as high as 46.8% (36/77) after feeding, and all Rickettsia spp. sequences recovered were most similar to those described from the spotted fever group Rickettsia, specifically R. amblyommii and R. massiliae. Additional characterization of the Rickettsiales tick community by polymerase chain reaction, cloning, and sequencing of 17 kDa and gltA genes confirmed these initial findings and suggested that novel Rickettsia spp. are likely present in these ticks. These data provide insight into the overall, as well as the rickettsial community of wild lone star ticks and may ultimately aid in identification of novel pathogens transmitted by A. americanum.
Walton, V M; Dreves, A J; Coop, L B; Jones, G V; Skinkis, P A
Developmental parameters of protogyne Calepitrimerus vitis (Nalepa) (Acari: Eriophyidae) were determined at 12, 15, 17, 22, 25, 28, 31, and 34 °C to better understand seasonal activity, population growth, and ultimately more effectively manage pest mites in wine grapes. Net reproductive rate (R(o)) was greater than zero at all temperatures with the maximum R(o) (9.72) at 25 °C. The lowest estimated R(o) (0.001) occurred at 34 °C. There was a gradual decrease in mean generation time (T) as temperatures increased from 17 to 31 °C. The shortest and longest generation time was recorded at 31 °C (T = 5.5 d) and 17 °C (T = 17.5 d). Rates of natural increase were lowest at 17°C (0.035) and increased with increasing temperatures, respectively. The peak rate of natural increase value (0.141) was at 25 °C. Estimations for minimum and maximum developmental thresholds were 10.51 and 39.19 °C, respectively, while the optimum developmental temperature was 26.9 °C. The thermal constant for egg to adult development was estimated at 87.7DD. The highest fecundity was observed at 25 °C. These parameters indicated that mites begin feeding at the onset of shoot growth when tissue is most susceptible in spring. Historical weather data showed that vines are in this susceptible growth stage for longer periods in the cool Willamette Valley compared with warmer Umpqua and Applegate/Rogue Valley regions. Estimation of degree-days indicated when deutogyne mites move to overwintering refuge sites. Degree-day accumulations indicated up to 14 generations per growing season.
Kensinger, B J; Allan, B F
The carbon dioxide-baited trap is the most common and effective method for sampling vector life-stage Amblyomma americanum (L.) (Acari: Ixodidae), although confounding environmental variables are rarely considered. A mark-recapture experiment was designed to compare recapture proportions of A. americanum nymphs and adults between two habitat types: old field and oak-hickory forest. Powdered fluorescent dye was used to mark A. americanum ticks released in 1-m increments from carbon dioxide-baited traps. Adults were recaptured in significantly higher proportion than nymphs, but habitat type had no significant effect on recapture proportions. Tick abundance is an important parameter in the estimation of human risk of exposure to tick-borne disease and the influence of life stage on capture rates should be considered when calculating entomological risk.
Caetano, Rebecca Leal; Vizzoni, Vinicius Figueiredo; Bitencourth, Karla; Carriço, Cesar; Sato, Tayra Pereira; Pinto, Zeneida Teixeira; De Oliveira, Stefan Vilges; Amorim, Marinete; Voloch, Carolina Moreira; Gazeta, Gilberto Salles
The Rhipicephalus sanguineus (Latreille) complex (Acari:Ixodidae) is composed of species with intra- and interspecific morphological variation that make their diagnosis difficult. In the present study, male specimens of the R. sanguineus complex were collected from dogs in six districts of three regions of Brazil and submitted to molecular and scanning electron microscopy (SEM) analyses. Analysis of COX1 gene, 12S rDNA, and D-loop rDNA shows that ticks classified as R. sanguineus form two different clades. Morphological comparisons using SEM found adult males to exhibit morphological differences in Haller's organ, festoons, and adanal, spiracular, and genital plates, with the last having potential usefulness in distinguishing male specimens of the complex. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.
Izdebska, Joanna N; Fryderyk, Sławomira; Rolbiecki, Leszek
A new species of demodecid mite, Demodex castoris sp. nov. (Acari: Prostigmata: Demodecidae), is described based on adult stages from the skin of the nasal region of the Eurasian beaver Castor fiber Linnaeus, 1758, collected in Poland. This is the first detection of a representative demodecid mite in rodents of the suborder Castorimorpha and also represents the first detection of a skin mite in Eurasian beavers. The new species is a small skin mite (average 173 µm in length) characterized by sexual dimorphism related to body proportions. D. castoris sp. nov. was observed in 4 out of 6 beavers examined (66.6%), with a mean intensity of 10.8 and an intensity range of 2-23 ind. host(-1). This paper also contains a checklist of parasitic arthropods known from Castor spp.
Li, Andrew Y; Davey, Ronald B; Miller, Robert J; Guerrero, Felix D; George, John E
The Santa Luiza strain of the southern cattle tick, Boophilus microplus (Canestrini) (Acari: Ixodidae), is resistant to both permethrin and amitraz. A study was conducted at the USDA Cattle Fever Tick Research Laboratory in Texas to investigate the genetic basis of permethrin resistance with cross-mating experiments, and to determine the mechanisms of permethrin resistance through synergist bioassays and biochemical analysis of esterase profiles. The Muñoz strain, an acaricide-susceptible reference strain, was used as the susceptible parent and the Santa Luiza strain, originating in Brazil, was used as the resistant parent. The Food and Agriculture Organization larval packet test was used to measure the levels of susceptibility of larvae of the parental strains, F1, backcross, F2, and F3 generations to permethrin. Results of reciprocal crossing experiments suggested that permethrin resistance was inherited as an incomplete recessive trait. There was no significant maternal effect on larval progeny's susceptibility to permethrin in the F1 and subsequent generations. The values of the degree of dominance were estimated at -0.700 and -0.522 for the F1 larvae with resistant and susceptible female parents, respectively. Results of bioassays on larval progeny of the F1 backcrossed with the resistant parent strain and of the F2 generations suggested that one major gene was responsible for permethrin resistance in the Santa Luiza strain. Selection of F3 larvae with either permethrin or amitraz led to significantly increased resistance to both permethrin and amitraz, indicating a close linkage between genes responsible for permethrin and amitraz resistance. The possible involvement of metabolic enzymes in permethrin resistance in the Santa Luiza strain of B. microplus was dismissed by the lack of enhanced synergism by TPP or PBO, as observed in synergist bioassays, as well as by the lack of enhanced esterase activity in the Santa Luiza strain relative to the susceptible
Martins, João R; Monticelli, Elida C; Onofrio, Valéria C; Barros-Battesti, Darcy M; Doyle, Rovaina L
Amblyomma fuscum known only from Brazil has been described as a rare tick species with few reports of its occurrence in South and Southeast region. This is a new records this tick species (9 females) parasitizing lizard (Tupinambis teguixin) at the Municipality of Glorinha, State of Rio Grande do Sul. The females were deposited in the tick collection of Veterinary Research Institute Desiderio Finamor (7 specimens), Eldorado do Sul, RS and in the Acari collection from Instituto Butantan, São Paulo, State of São Paulo (2 specimens). The finding confirms establishment de A. fuscum in the South of Brazil.
de Souza, Clarissa Pimentel; Verocai, Guilherme Gomes; de Arruda, Julio Almeida Alencar Matos; Pires, Jeferson Rocha; Takitani, Andréa Yuri; Faccini, João Luiz Horacio
The aim of this paper is to report the first description of gross pathological aspects of otoacariasis due to Edentalges bradypus Fonseca 1954 (Acari; Psoroptidae) infestation in the brown-throated three-toed sloth Bradypus variegatus Schinz, 1825 (Xenarthra; Bradypodidae) in Brazil. Mites were collected from massive skin crusts seen in both external ear canals and around both eyes of an extremely debilitated advanced-aged female sloth brought to the Wildlife Care Section of Universidade Estácio de Sá, Rio de Janeiro, Brazil.
Proudfoot, Glenn A; Teel, Pete D; Mohr, Rachel M
While banding ferruginous pygmy-owls (Glaucidium brasilianum) and Eastern screech-owls (Megascops asio) in south Texas during 2004, we recorded Philornis mimicola (Diptera: Muscidae) and Ornithodoros concanensis (Acari: Argasidae) parasitizing nestlings. Inspection of nestlings revealed 54 P. mimicola and one O. concanensis. Inspection of nest material revealed 111 P. mimicola, including 57 puparia. The effect (e.g., blood loss, anemia) of these hematophagous parasites might have contributed to the demise of at least one Eastern screech-owl nestling. This is the first record of P. mimicola and O. concanensis parasitizing ferruginous pygmy-owls and Eastern screech-owls.
Hajiqanbar, Hamidreza; Mortazavi, Abdolazim
Two new species of Eutarsopolipus Berlese, 1911 (Acari: Heterostigmatina: Podapolipidae), belonging to the myzus species group, are described from the subelytra of carabid beetles (Coleoptera: Carabidae) in Iran. Eutarsopolipus anichtchenkoi n. sp. was found on Pterostichus sp. and E. terricolae n. sp. on Scarites terricola Bonelli. This is the first record of the myzus species group from Asia. A key to the adult females of this species group worldwide is provided, and the distribution and host range of all representatives of the group are discussed.
Billeter, Sarah A; Miller, Melissa K; Breitschwerdt, Edward B; Levy, Michael G
Four hundred and sixty-six questing Amblyomma americanum (L.) (Acari: Ixodidae) from Carolina County, VA, and 98 questing A. americanum from Chatham County, NC, were screened by polymerase chain reaction (PCR) for the Bartonella 16S-23S intergenic spacer region. Two amplicons, approximately 270-280 bp, were detected in two ticks from Virginia. Based upon PCR and sequencing, an adult male and adult female tick harbored DNA sequences closely related to Bartonella tamiae (DQ395180). Bartonella DNA was not detected in A. americanum from North Carolina. Potential transmission of Bartonella spp. by A. americanum should be the focus of future experimental studies.
Reeves, Will K; Durden, Lance A; Dasch, Gregory A
Adults and nymphs of Amblyomma exornatum Koch (Acari: Ixodidae), an exotic African tick of monitor lizards, were collected from a Gray's monitor lizard, Varanus olivaceus Hallowell, that died in a reptile facility in Alabama. Nine adult ticks were tested by polymerase chain reaction for rickettsial agents. DNA from a novel spotted fever group Rickettsia was amplified and sequenced from one of the nine ticks. The novel Rickettsia was most similar to "Rickettsia anan," which is associated with Amblyomma from Asia. The detection of a spotted fever group Rickettsia in exotic ticks emphasizes the potential threat posed by the importation and propagation of exotic animals in the United States.
Bochkov, A V
The phenomenon of the parallel evolution is considered with the example of the myobiid mites (Acari: Prostigmata: Myobiidae) and the jerboas (Rodentia: Dipodoidea). According to recent phylogenetic studies of the superfamily Dipodoidea it is separated into 4 family: Allactagidae, Dipodidae, Zapodidae and Sminthidae (Shenbrot e. a., 1995). The myobiid mites of the subenus Dipodomyobia (11 species) of the genus Cryptomyobia are known as specific parasites associated with jerboas of the families Dipodidae and Allactagidae. One more species (Radfordia ewingi) considered as incertae sedis species within the genus Radfordia is found on the jerboas of the family Zapodidae. The myobiid mites are apparently absent on the members of the family Sminthidae. The reconstruction of phylogeny of the myobiid subgenus Dipodomyobia was carried out by the cladistic method (software PAUP 3.0 s). The analysis was based on 13 morphological characters. At the first step of analysis 42 parsimonious trees have been obtained. The strict consensus tree displays one distinct cluster, which incorporates mites of the allactaga species of group restricted to the jerboa family Allactagidae, and several plesions, species of which are usually refferred to as dipi species group and associated with the family Dipodidae (fig. 1). At the second step of analysis, two characters, which appeared as homoplasies at the first step of analysis were excluded, and one new characters (structure of male genital shield) was additionally included. Single cladogram obtained displays two general clusters and one plesion. The first cluster comprises the allactaga species group (parasites of Allactagidae). The second cluster incorporates the dipi species group, the parasites of subfamilies Dipodinae and Paradipodinae of Dipodidae). The plesion is represented by one species Cryptomyobia baranovae being a specific parasite of Salpingotus crassicauda (Cardiocraninae, Dipodidae). There is the high level congruence between
Wright, S A; Tucker, J R; Donohue, A M; Castro, M B; Kelley, K L; Novak, M G; Macedo, P A
Larval and nymphal western blacklegged tick, Ixodes pacificus Cooley & Kohls (Acari: Ixodidae), were collected from birds, rodents, and lizards at Quail Ridge Reserve located in Napa County in northwestern California. Species from three vertebrate classes were sampled simultaneously from two transects during two consecutive spring seasons. Feeding larval and nymphal ticks were removed and preserved for counting, examination and testing for the presence of Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner. Mean infestations with I. pacificus subadults on lizards were 10.0, on birds 2.9, and on rodents 1.3. I. pacificus larvae (204) collected from 10 avian species and (215) collected from two rodent species were tested for the presence of B. burgdorferi s.s. via real-time polymerase chain reaction. Three B. burgdorferi-infected larvae were taken from two Junco hyemalis and two infected larvae from one Neotoma fuscipes Baird. This is the detection of B. burgdorferi ss in an Ixodes pacificus larvae feeding on a Junco hyemalis L., [corrected] in western North America.
The problem of the unnatural transfer of exotic ticks (Acari: Ixodida) on reptiles (Reptilia) imported to Poland is presented. In the period from 2003 to 2007, 382 specimens of reptiles belonging to the following genera were investigated: Testudo, Iguana, Varanus, Gongylophis, Python, Spalerosophis, Psammophis. The reptiles most infested with ticks are imported to Poland from Ghana in Africa, and are the commonly bred terrarium reptiles: Varanus exanthematicus and Python regius. As a result of the investigations, the transfer of exotic ticks on reptiles to Poland was confirmed. There were 2104 specimens of the genera Amblyomma and Hyalomma. The following species were found: Amblyomma exornatum Koch, 1844, Amblyomma flavomaculatum (Lucas, 1846), Amblyomma latum Koch, 1844, Amblyomma nuttalli Donitz, 1909, Amblyomma quadricavum (Schulze, 1941), Amblyomma transversale (Lucas, 1844), Amblyomma varanense (Supino, 1897), Amblyomma sp. Koch, 1844, Hyalomma aegyptium (Linnaeus, 1758). All the species of ticks of genus Amblyomma revealed have been discovered in Poland for the first time. During the research, 13 cases of anomalies of morphological structure were confirmed in the ticks A. flavomaculatum, A. latum and H. aegyptium. The expanding phenomenon of the import of exotic reptiles in Poland and Central Europe is important for parasitological and epidemiological considerations, and therefore requires monitoring and wide-ranging prophylactic activities to prevent the inflow of exotic parasites to Poland.
Rodrigues, Jose Carlos Verle; Irish, Brian M
Although coconut (Cocos nucifera L.) is the predominant host for Raoiella indica Hirst (Acari: Tenuipalpidae), false spider mite infestations do occur on bananas and plantains (Musa spp. Colla). Since its introduction, the banana and plantain industries have been negatively impacted to different degrees by R. indica infestation throughout the Caribbean. Genetic resistance in the host and the proximity of natural sources of mite infestation has been suggested as two of the main factors affecting R. indica densities in Musa spp. plantations. Greenhouse experiments were established to try to determine what effect coconut palm proximities and planting densities had on R. indica populations infesting Musa spp. plants. Trials were carried out using potted Musa spp. and coconut palms plants at two different ratios. In addition, fourteen Musa spp. hybrid accessions were evaluated for their susceptibility/resistance to colonization by R. indica populations. Differences were observed for mite population buildup for both the density and germplasm accession evaluations. These results have potential implications on how this important pest can be managed on essential agricultural commodities such as bananas and plantains.
Nava, Santiago; Mangold, Atilio J; Mastropaolo, Mariano; Venzal, José M; Oscherov, Elena B; Guglielmone, Alberto A
All parasitic stages of Amblyomma boeroi n. sp. (Acari: Ixodidae) are described here from Catagonus wagneri (Rusconi) in Argentina. The diagnostic characters for the male are a combination of orbited eyes, a 2/2 dental formula, coxa IV considerably larger than coxae I-III and with a long, sickle-shaped, medially directed spur arising from its internal margin, a scutum which is light grey to very pale ivory in colour, and the absence of a postanal groove. The diagnostic characters for the females are a combination of orbited eyes, a central pair and two marginal pairs of short, coarse notal setae, a 2/2 dental formula, and the absence of a postanal groove. The nymph has short palpi and a 2/2 dental formula arranged in 6 rows, its eyes are convex and orbited, and it has no postanal groove. The dorsally rectangular basis capituli of the larva, its bulging eyes and slightly sinuous posterior scutal margin all serve to distinguish it from the larva of other species of the genus. The principal host for all parasitic stages is C. wagneri (Artiodactyla: Tayassuidae). Phylogenetically A. boeroi appears to represent an independent lineage within Amblyomma Koch, 1844.
Ermilov, Sergey G; Minor, Maria A
Three new species of oribatid mites of the family Punctoribatidae (Acari, Oribatida) are described from alpine bogs of the Central Otago region in the South Island of New Zealand. Macrogena hexasetosa sp. nov. is morphologically most similar to M. brevisensilla Ermilov & Minor, 2015, however, it differs from the latter by larger body size, the presence of six pairs of genital setae, notogastral and ano-adanal setae of medium size, setiform rostral setae, narrower tutorial cusps, the absence of antero-ventral teeth on genua I, II and femora II, and by the absence of striae on the subcapitular mentum. Porallozetes badamdorji sp. nov. differs from the type species-P. dispar (Hammer, 1973)-by larger body length, the presence of interlamellar setae, short and clavate bothridial setae, anterior notogastral margin, notogastral setae of medium size, semi-oval dorsophragmata, and by the position of notogastral porose areas A2 posteriorly to A1. Safrobates gerdi sp. nov. differs from the type species-S. miniporus Mahunka, 1989-by larger body size, the presence of setiform rostral setae, and by notogastral setae of medium length. Porallozetes and Safrobates are recorded in New Zealand for the first time. Generic diagnoses for Macrogena, Porallozetes and Safrobates are given.
Vandervalk, L P; Nasr, M E; Dosdall, L M
Varroa destructor Anderson and Trueman 2000 (Acari: Varroidae) is an ectoparasitic mite of the honey bee, Apis mellifera L. (Hymenoptera: Apidae). Honey bee colonies require extensive management to prevent mortality caused by varroa mites and the viruses they vector. New miticides (Thymovar and HopGuard) to manage varroa mites were evaluated during the spring and fall treatment windows of the Canadian prairies to determine their effectiveness as part of an integrated management strategy. Thymovar and HopGuard were evaluated alongside the currently used industry standards: Apivar and formic acid. Results demonstrated that Apivar and formic acid remain effective V. destructor management options under spring and fall conditions. Applications of Thymovar during spring were associated with a reduction in brood area, and therefore should be limited to the fall season. The miticide HopGuard was not effective in managing V. destructor, and alteration of the current delivery system is necessary. This study demonstrates the potential for new effective treatment options to supplement currently used V. destructor integrated pest management systems.
Szafranek, Piotr; Lewandowski, Mariusz; Kozak, Marcin
Parasitus bituberosus Karg (Acari: Parasitidae) is one of the predatory mite species inhabiting mushroom houses. It is known to accept a wide range of prey, suggesting that it may be a promising candidate for the biological control of key pests of mushroom culture. In our study it did not show any prey preference among four groups of small organisms often occurring in mushroom growth medium, namely rhabditid nematodes, pygmephorid mites, and sciarid and phorid fly larvae. Nevertheless, the type of food these predators fed on affects their development. The shortest egg-to-adult development time was obtained on a nematode diet. On a diet of phorid larvae, mite development stopped at the deutonymph stage; none reached adulthood. All other diets sufficed to reach the adult phase. Female fecundity when fed nematodes and sciarid larvae did not differ, but it was much lower when fed pygmephorid mites. Other life table parameters confirmed that pygmephorid mites constituted the worst diet for P. bituberosus. The highest intrinsic rate of population increase (r m = 0.34) was obtained on the nematode diet; when fed sciarid larvae and pygmephorid mites it was 0.25 and 0.14, respectively. Our study provides good reasons to further test P. bituberosus as biocontrol agent of especially sciarid flies and nematodes, especially when the compost is well colonized by mushroom mycelium (which retards nematode growth).
Napierała, Agnieszka; Mądra, Anna; Leszczyńska-Deja, Kornelia; Gwiazdowicz, Dariusz J; Gołdyn, Bartłomiej; Błoszyk, Jerzy
Underground nests of Talpa europaea, known as the common mole, are very specific microhabitats, which are also quite often inhabited by various groups of arthropods. Mites from the suborder Uropodina (Acari: Mesostigmata) are only one of them. One could expect that mole nests that are closely located are inhabited by communities of arthropods with similar species composition and structure. However, results of empirical studies clearly show that even nests which are close to each other can be different both in terms of the species composition and abundance of Uropodina communities. So far, little is known about the factors that can cause these differences. The major aim of this study was to identify factors determining species composition, abundance, and community structure of Uropodina communities in mole nests. The study is based on material collected during a long-term investigation conducted in western parts of Poland. The results indicate that the two most important factors influencing species composition and abundance of Uropodina communities in mole nests are nest-building material and depth at which nests are located. Composition of Uropodina communities in nests of moles was also compared with that of other microhabitats (e.g. rotten wood, forest litter, soil) based on data from 4421 samples collected in Poland. Communities of this habitat prove most similar to these of open areas, especially meadows, as well as some forest types.
Zindel, Renate; Ofek, Maya; Minz, Dror; Palevsky, Eric; Zchori-Fein, Einat; Aebi, Alexandre
The biology of many arthropods can only be understood when their associated microbiome is considered. The nutritional requirements of the bulb mite Rhizoglyphus robini Claparede (Acari: Astigmata: Acaridae) in the laboratory have been shown to be very easily satisfied, and in the field the mites prefer fungus-infected over uninfected plants. To test whether symbiotic bacteria facilitate the survival of R. robini on a temporarily nutritionally unbalanced diet, we investigated the composition of its microbiome. Using 454 pyrosequencing of 16S rRNA gene fragments, 3 genera were found to dominate the bacterial community: Myroides (41.4%), Serratia (11.4%), and Alcaligenes (4.5%); the latter 2 are known to include chitinase-producing species. Laboratory experiments demonstrated that mite fecundity is significantly higher (2 times) on fungus than on controls (sterilized potato dextrose agar and filter paper). Also, when mite homogenate was applied to a chitin layer, the halo produced through degradation was clearly visible, while the saline control did not produce a halo. We thus concluded that R. robini utilizes fungal chitin, at least to a certain extent, as a food source with the help of its associated bacteria. This information supports the general concept of multigenome organisms and the involvement of bacteria in the mite's nutritional ecology.
Erdmann, Georgia; Scheu, Stefan; Maraun, Mark
Most European forests are managed by humans. However, the manner and intensity of management vary. While the effect of forest management on above-ground communities has been investigated in detail, effects on the below-ground fauna remain poorly understood. Oribatid mites are abundant microarthropods in forest soil and important decomposers in terrestrial ecosystems. Here, we investigated the effect of four forest types (i.e., managed coniferous forests; 30 and 70 years old managed beech forests; natural beech forests) on the density, diversity and community structure of oribatid mites (Acari). The study was replicated at three regions in Germany: the Swabian Alb, the Hainich and the Schorfheide. To relate changes in oribatid mite community structure to environmental factors, litter mass, pH, C and N content of litter, fine roots and C content of soil were measured. Density of oribatid mites was highest in the coniferous forests and decreased in the order 30 years old, 70 years old, and natural beech forests. Mass of the litter layer and density of oribatid mites were strongly correlated indicating that the litter layer is an important factor regulating oribatid mite densities. Diversity of oribatid mites was little affected by forest type indicating that they harbor similar numbers of niches. Species composition differed between the forest types, suggesting different types of niches. The community structure of oribatid mites differed more strongly between the three regions than between the forest types indicating that regional factors are more important than effects associated with forest type.
Dantas-Torres, Filipe; Giannelli, Alessio; Figueredo, Luciana Aguiar; Otranto, Domenico
The widespread geographical distribution of the brown dog tick Rhipicephalus sanguineus (Acari: Ixodidae) is related to the cosmopolitan distribution of its primary host and to its adaptability to different environments, under variable climate conditions. Field studies have suggested that temperature is the most important factor driving the population dynamics of this tick species. In order to investigate the effects of prolonged exposure to low temperature on eggs of R. sanguineus, nine groups (II-X) of five egg batches each were maintained at 8+/-2 degrees C (70+/-10% RH, and scotophase) for 15, 30, 45, 60, 75, 90, 105, 120, and 135 days. One group (group I) was maintained in the incubator (26+/-1 degrees C, 70+/-10% RH, and scotophase) and used as control. The mean egg incubation period from group I was 11.6+/-0.5 days, with an egg hatch rate of 99.5+/-0.5%. Conversely, no egg hatched at 8 degrees C. Exposure to cold showed a strong positive correlation with egg incubation period (r=0.99) as well as a strong negative correlation with egg hatch rate (r=-0.95) and larval longevity (r=-0.99). Overall, the present results points out that R. sanguineus eggs are sensible to prolonged exposure to low temperature, which is definitely a major limiting factor for the establishment of populations of this tick in cold temperate regions. Copyright 2010 Elsevier B.V. All rights reserved.
Che Lah, Ernieenor Faraliana; Yaakop, Salmah; Ahamad, Mariana; Md Nor, Shukor
Abstract Blood meal analysis (BMA) from ticks allows for the identification of natural hosts of ticks (Acari: Ixodidae). The aim of this study is to identify the blood meal sources of field collected on-host ticks using PCR analysis. DNA of four genera of ticks was isolated and their cytochrome b (Cyt b) gene was amplified to identify host blood meals. A phylogenetic tree was constructed based on data of Cyt b sequences using Neighbor Joining (NJ) and Maximum Parsimony (MP) analysis using MEGA 5.05 for the clustering of hosts of tick species. Twenty out of 27 samples showed maximum similarity (99%) with GenBank sequences through a Basic Local Alignment Search Tool (BLAST) while 7 samples only showed a similarity range of between 91–98%. The phylogenetic trees showed that the blood meal samples were derived from small rodents (Leopoldamys sabanus, Rattus tiomanicus and Sundamys muelleri), shrews (Tupaia glis) and mammals (Tapirus indicus and Prionailurus bengalensis), supported by 82–88% bootstrap values. In this study, Cyt b gene as a molecular target produced reliable results and was very significant for the effective identification of ticks’ blood meal. The assay can be used as a tool for identifying unknown blood meals of field collected on-host ticks. PMID:25685009
Corn, Joseph L; Berger, Patrick; Mertins, James W
Surveys in 2001, 2005, and 2006 attempted to determine the role of wildlife in maintenance and dissemination of the tropical bont tick, Amblyomma variegatum (F.) (Acari: Ixodidae), in St. Croix, U.S. Virgin Islands. Small mammals; birds; white-tailed deer, Odocoileus virginianus (Zimmermann); and feral cattle, Bos taurus L., were examined at nine premises, in mountainous rain forest, and in surrounding areas in western St. Croix, an area including and central to all known bont tick-infested premises on the island. Small Asian mongooses, Herpestes javanicus (E. Geoffroy Saint-Hilaire), yielded 1,566 ectoparasite specimens, representing five species, and including larvae of a soft tick, Carios puertoricensis (Fox); the tropical horse tick, Anocentor nitens (Neumann); and the southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini). Black rats, Rattus rattus L., yielded 144 specimens, representing six ectoparasite species, including C. puertoricensis. Of 25 bird species examined, seven yielded 116 ectoparasite specimens representing at least 14 different species of lice and mites, but no ticks. White-tailed deer and feral cattle yielded only various stages of A. nitens and R. microplus ticks. A. variegatum was not encountered on any potential wildlife host sampled, reflecting its low occurrence in St. Croix during the survey period. One collection of chewing lice (Phthiraptera: Philopteridae) from a spotted sandpiper, Actitis macularia (L.), and collections of feather mites (Acari: Astigmata: Trouessartiidae) from both bananaquits, Coereba flaveola (L.), and black-faced grassquits, Tiaris bicolor (L.), may represent new, undescribed species.
Bochkov, A V
The external morphological adaptations to parasitism in acariform mites (Acari: Acariformes), permanently parasiting mammals, are briefly summated and analyzed. According to several external morphological criteria (structures of gnathosoma, idiosoma, setation, legs and life cycle), the following six morphoecotypes were established: skin mites (i)-- Cheyletidae, Chirorhynchobiidae, Lobalgidae, Myobiidae, Myocoptidae (the most part), Rhyncoptidae, Psoroptidae; fur mites (ii)--Atopomelidae, Clirodiscidae, Listrophoridae, Myocoptidae (Trichoecius only); skin burrowing mites (iii)--Sarcoptidae; intradermal mites (iv) - sorergatidae and Demodicidae; interstitial mites (v) - pimyodicidae; respiratory mites (vi) - reynetidae, Gastronyssidae, Lemurnyssidae, Pneumocoptidae. In the case of prostigmatic mites, the detailed reconstruction of the origin and evolution of "parasitic" morphoecotypes is possible due to the tentative phylogenetic hypotheses, which were proposed for the infraorder Eleutherengon, a, including the most part of the permanent mammalian parasites among prostigmatic mites (Kethley in Norton, 1993; Bochkov, 2002). The parasitism of Speleognathinae (Ereynetidae) in the mammalian respiratory tract arose independently of the other prostigmats. It is quite possible that these mites switched on mammals from birds, because they are more widely represented on these hosts than on mammals. The prostigmatic parasitism on mammalian skin seems to be originated independently in myobiids, in the five cheyletid tribes, Cheyletiellini, Niheliini, and Teinocheylini, Chelonotini, Cheyletini, and, probably, in a cheyletoid ansector of the sister families Psorergatidae-Demodicidae (Bochkov, Fain, 2001; Bochkov, 2002). Demodicids and psorergatids developed adaptations to parasitism in the skin gland ducts and directly in the epithelial level, respectively in the process of the subsequent specialization. Mites of the family Epimyodicidae belong to the phylogenetic line
Kreipe, Victoria; Corral-Hernández, Elena; Scheu, Stefan; Schaefer, Ina; Maraun, Mark
Species of the genus Steganacarus are soil-living oribatid mites (Acari, Phthiracaridae) with a ptychoid body. The phylogeny and species status of the species of Steganacarus are not resolved, some authors group all ten German species of Steganacarus within the genus Steganacarus whereas others split them into three subgenera, Steganacarus, Tropacarus and Atropacarus. Additionally, two species, S. magnus and T. carinatus, comprise morphotypes of questionable species status. We investigated the phylogeny and species status of ten European Steganacarus species, i.e. S. applicatus, S. herculeanus, S. magnus forma magna, S. magnus forma anomala, S. spinosus, Tropacarus brevipilus, T. carinatus forma carinata, T. carinatus forma pulcherrima, Atropacarus striculus and Rhacaplacarus ortizi. We used two molecular markers, a 251 bp fragment of the nuclear gene 28S rDNA (D3) and a 477 bp fragment of the mitochondrial COI region. The phylogeny based on a combined analysis of D3 and COI separated four subgenera (Steganacarus, Tropacarus and Atropacarus, Rhacaplacarus) indicating that they form monophyletic groups. The COI region separated all ten species of the genus Steganacarus and showed variation within some species often correlating with the geographic origin of the species. Resolution of the more conserved D3 region was limited, indicating that radiation events are rather recent. Overall, our results indicate that both genes alone cannot be used for phylogeny and barcoding since variation is too low in D3 and too high in COI. However, when used in combination these genes provide reliable insight into the phylogeny, radiation and species status of taxa of the genus Steganacarus.
Wang, Zhangqian; Kim, Hyun-Kyung; Tao, Wenqi; Wang, Mo; Ahn, Young-Joon
Toxicities of (E)-cinnamaldehyde and (E)-cinnamic acid and their 41 structurally related compounds to adult Dermatophagoides farinae Hughes and Dermatophagoides pteronyssinus Trouessart (Acari: Pyroglyphidae) were examined using fabric-circle contact plus fumigant and vapor-phase mortality bioassays. Results were compared with those of two acaricides, benzylbenzoate and dibutyl phthalate. In contact plus fumigant mortality bioassays, the most toxic compounds were (E)-cinnamaldehyde, methyl (E)-cinnamate, cinnamyl acetate, and hydrocinnamaldehyde against adult D.farinae (17.5-23.3 mg/m2) and D. pteronyssinus (19.0-24.0 mg/m2), based on 24-h 50% lethal concentration (LC50) values. These compounds were significantly more toxic than either benzyl benzoate (LC50, 64.9 and 60.5 mg/m2) or dibutyl phthalate (218.9 and 232.3 mg/m2). The toxicity of allyl cinnamate versus benzyl benzoate was not significantly different. Structure-activity relationship indicates that structural characteristics, such as types of functional groups, carbon skeleton, and saturation, appear to play a role in determining the compound toxicities. In vapor-phase mortality bioassays, these compounds were effective against adult D. farinae in closed, but not in open containers, indicating that their mode of delivery was largely a result of vapor action. The active compounds described merit further study as potential house dust mite control fumigants with contact action in light of global efforts to reduce the level of highly toxic synthetic acaricides in indoor environments.
Nchu, F; Maniania, N K; Touré, A; Hassanali, A; Eloff, J N
Experiments were conducted to explore the use of a semiochemical bait to enhance exposure of Amblyomma variegatum Fabricius (Acari: Ixodidae) to different formulations of the entomopathogenic fungus Metarhizium anisopliae (Metsch.) Sorok. (Ascomycota: Hypocreales). Initially, the relative efficacies of attraction-aggregation-attachment pheromone (AAAP), made up of o-nitrophenol, methyl salicylate and nonanoic acid in the ratio 2:1:8, 1-octen-3-ol and butyric acid, were evaluated in an olfactometer. Only AAAP and 1-octen-3-ol were found to elicit attractive responses to the tick. Simultaneous release of 1-octen-3-ol and AAAP together with CO(2) from a trap in semifield plots attracted up to 94.0+/-6% of adult ticks from a distance of 6m, and up to 24.0+/-5.1% from 8m. Formulations of M. anisopliae (dry powder, oil, and emulsifiable) applied within the trap baited with AAAP, 1-octen-3-ol and CO(2) resulted in high levels of contamination of the ticks attracted to the traps. However, 48h after autoinoculation, 89.1 and 33.3% of conidia were lost in dry powder and oil formulations, respectively. Emulsifiable formulation showed least loss of propagules (17.1%). Samples of ticks attracted to the baited traps were transferred to plastic basins containing grass and maintained for 5 weeks. The experiment was conducted in rainy and dry seasons. Emulsifiable formulation gave the highest relative tick reduction in both seasons: 54.7 and 46.5% in rainy and dry seasons, respectively, followed by oil formulation (32.0 and 23.8%) and powder formulation (38.0 and 24.4%).
Johnson, Tammi L; Graham, Christine B; Boegler, Karen A; Cherry, Cara C; Maes, Sarah E; Pilgard, Mark A; Hojgaard, Andrias; Buttke, Danielle E; Eisen, Rebecca J
Tick-borne pathogens transmitted by Ixodes scapularis Say (Acari: Ixodidae), also known as the deer tick or blacklegged tick, are increasing in incidence and geographic distribution in the United States. We examined the risk of tick-borne disease exposure in 9 national parks across six Northeastern and Mid-Atlantic States and the District of Columbia in 2014 and 2015. To assess the recreational risk to park visitors, we sampled for ticks along frequently used trails and calculated the density of I. scapularis nymphs (DON) and the density of infected nymphs (DIN). We determined the nymphal infection prevalence of I. scapularis with a suite of tick-borne pathogens including Borrelia burgdorferi, Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia microti. Ixodes scapularis nymphs were found in all national park units; DON ranged from 0.40 to 13.73 nymphs per 100 m2. Borrelia burgdorferi, the causative agent of Lyme disease, was found at all sites where I. scapularis was documented; DIN with B. burgdorferi ranged from 0.06 to 5.71 nymphs per 100 m2. Borrelia miyamotoi and A. phagocytophilum were documented at 60% and 70% of the parks, respectively, while Ba. microti occurred at just 20% of the parks. Ixodes scapularis is well established across much of the Northeastern and Mid-Atlantic States, and our results are generally consistent with previous studies conducted near the areas we sampled. Newly established I. scapularis populations were documented in two locations: Washington, D.C. (Rock Creek Park) and Greene County, Virginia (Shenandoah National Park). This research demonstrates the potential risk of tick-borne pathogen exposure in national parks and can be used to educate park visitors about the importance of preventative actions to minimize tick exposure. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by US Government employees and is in the public domain in the US.
Ogrzewalska, Maria; Nieri-Bastos, Fernanda A; Marcili, Arlei; Nava, Santiago; González-Acuña, Daniel; Muñoz-Leal, Sebastián; Ruiz-Arrondo, Ignacio; Venzal, José M; Mangold, Atilio; Labruna, Marcelo B
The tick Amblyomma parvitarsum (Acari: Ixodidae) has established populations in Andean and Patagonic environments of South America. For the present study, adults of A. parvitarsum were collected in highland areas (elevation >3500 m) of Argentina and Chile during 2009-2013, and tested by PCR for rickettsial infection in the laboratory, and isolation of rickettsiae in Vero cell culture by the shell vial technique. Overall, 51 (62.2%) out of 82 A. parvitarsum adult ticks were infected by spotted fever group (SFG) rickettsiae, which generated DNA sequences 100% identical to each other, and when submitted to BLAST analysis, they were 99.3% identical to corresponding sequence of the ompA gene of Rickettsia sp. strain Atlantic rainforest. Rickettsiae were successfully isolated in Vero cell culture from two ticks, one from Argentina and one from Chile. DNA extracted from the third passage of the isolates of Argentina and Chile were processed by PCR, resulting in partial sequences for three rickettsial genes (gltA, ompB, ompA). These sequences were concatenated and aligned with rickettsial corresponding sequences available in GenBank. Phylogenetic analysis revealed that the A. pavitarsum rickettsial agent grouped under high bootstrap support in a clade composed by the SFG pathogens R. sibirica, R. africae, R. parkeri, Rickettsia sp. strain Atlantic rainforest, and two unnamed SFG agents of unknown pathogenicty, Rickettsia sp. strain NOD, and Rickettsia sp. strain ApPR. The pathogenic role of this A. parvitarsum rickettsia cannot be discarded, since several species of tick-borne rickettsiae that were considered nonpathogenic for decades are now associated with human infections.
Vázquez, Luís; Panadero, Rosario; Dacal, Vicente; Pato, Francisco Javier; López, Ceferino; Díaz, Pablo; Arias, María Sol; Fernández, Gonzalo; Díez-Baños, Pablo; Morrondo, Patrocinio
During the 2007 and 2008 hunting seasons (April-October) the skin of 367 roe deer (Capreolus capreolus L.), hunted in different preserves from Galicia (Northwestern Spain), were examined for ticks (Acari: Ixodidae). The overall prevalence of infestation by ticks was 83.1%. The predominant species was Ixodes ricinus (83.1%), whereas a single Dermacentor marginatus specimen appeared in one roe deer. All developmental stages of I. ricinus were found parasitizing roe deer, the adults being the most frequent (82.2%), followed by nymphs (45.6%) and larvae (27.2%). The mean intensity of infestation by I. ricinus was 43.2 ± 49.85; most of them were adults (30.7 ± 31.64) and in a lesser extend nymphs (16.9 ± 24.74) and larvae (10.7 ± 29.90). Ixodes ricinus was present all over the study with percentages that oscillated between 100% in spring and 57.4% in autumn. CHAID algorithm showed the sex of roe deer as the most influential factor in tick prevalence, followed by the climatic area. The different developmental stages of I. ricinus were more frequent in males than in females, and the prevalence of adults and larvae were higher in roe deer from coastal areas than in those from mountainous and central areas, whereas nymphs were more frequent in mountainous areas. Host age and density were not determinants for tick infestation. Our results confirm that roe deer are important hosts for I. ricinus in northwestern Spain, serving as a vehicle for the geographic distribution of these ticks.
Wantuch, Holly A; Tarpy, David R
The parasitic mite Varroa destructor Anderson & Trueman (Acari: Varroidae) has plagued European honey bees, Apis mellifera L. (Hymenoptera: Apidae), in the Americas since its introduction in the 1980s. For many years, these mites were sufficiently controlled using synthetic acaricides. Recently, however, beekeepers have experienced increased resistance by mites to chemical pesticides, which are also known to leave residues in hive products such as wax and honey. Thus there has been increased emphasis on nonchemical integrated pest management control tactics for Varroa. Because mites preferentially reproduce in drone brood (pupal males), we developed a treatment strategy focusing on salvaging parasitized drones while removing mites from them. We removed drone brood from colonies in which there was no acaricidal application and banked them in separate "drone-brood receiving" colonies treated with pesticides to kill mites emerging with drones. We tested 20 colonies divided into three groups: 1) negative control (no mite treatment), 2) positive control (treatment with acaricides), and 3) drone-brood removal and placement into drone-brood receiving colonies. We found that drone-brood trapping significantly lowered mite numbers during the early months of the season, eliminating the need for additional control measures in the spring. However, mite levels in the drone-brood removal group increased later in the summer, suggesting that this benefit does not persist throughout the entire season. Our results suggest that this method of drone-brood trapping can be used as an element of an integrated control strategy to control varroa mites, eliminating a large portion of the Varroa population with limited chemical treatments while retaining the benefits of maintaining adult drones in the population.
Immediato, Davide; Camarda, Antonio; Iatta, Roberta; Puttilli, Maria Rita; Ramos, Rafael Antonio Nascimento; Di Paola, Giancarlo; Giangaspero, Annunziata; Otranto, Domenico; Cafarchia, Claudia
The poultry red mite, Dermanyssus gallinae (De Geer, 1778) (Acari: Dermanyssidae) is one of the most economically important ectoparasites of laying hens worldwide. Chemical control of this mite may result in environmental and food contamination, as well as the development of drug resistance. High virulence of Beauveria bassiana sensu lato strains isolated from naturally infected hosts or from their environment has been demonstrated toward many arthropod species, including ticks. However, a limited number of studies have assessed the use of B. bassiana for the control of D. gallinae s.l. and none of them have employed native strains. This study reports the pathogenicity of a native strain of B. bassiana (CD1123) against nymphs and adults of D. gallinae. Batches of nymph and adult mites (i.e., n=720 for each stage) for treated groups (TGs) were placed on paper soaked with a 0.1% tween 80 suspension of B. bassiana (CIS, 10(5), 10(7) and 10(9) conidia/ml), whilst 240 untreated control mites for each stage (CG) were exposed only to 0.1% tween 80. The mites in TG showed a higher mortality at all stages (p<0.01) when compared to CG, depending on the time of exposure and the conidial concentration. A 100% mortality rate was recorded using a CIS of 10(9) conidia/ml 12 days post infection (DPI) in adults and 14 DPI in nymphs. B. bassiana suspension containing 10(9) conidia/ml was highly virulent towards nymph and adult stages of D. gallinae, therefore representing a possible promising natural product to be used in alternative or in combination to other acaricidal compounds currently used for controlling the red mite.
Nava, Santiago; Mastropaolo, Mariano; Mangold, Atilio J; Martins, Thiago F; Venzal, José M; Guglielmone, Alberto A
All stages of Amblyomma hadanii n. sp. (Acari: Ixodidae) are described from northwestern Argentina. The diagnostic characters for males are a combination of the pattern of scutal ornamentation, basis capituli dorsally rectangular with cornua, coxa I with two subequal spurs (the internal wider, the external longer), coxae II-III with a single spur, coxa IV with a single spur not reaching level of anus, ventral plates irregular in shape (larger and sometimes with a small incision on festoons 4, 5 and 6) and hypostome spatulate with dental formula 3/3 in 7-8 rows. The diagnostic characters for the females are a combination of scutal ornamentation, postero-lateral margins of scutum slightly convex, coxa I with two subequal spurs (the internal wider, the external longer), basis capituli dorsally rectangular, porose areas rounded, genital aperture U-shaped, and hypostome spatulate with dental formula 3/3 in 7-8 rows. Diagnosis of nymphs can be performed by a combination of basis capituli rectangular, scutum with large punctations in the lateral fields and small punctations in the central field, and cervical groove short and ending as a small shallow depression at the eye level. Larvae are diagnosed by the shape of basis capituli, scutum with with posterior margin slightly convex, and legs with coxa I with 2 triangular spur (the external longer than the internal), and with coxae II and III each with 1 triangular spur. The hosts recorded for this new tick species are Tapirus terrestris (Linnaeus), horse, cattle, dog and humans. Analyses of a 410 bp fragment of the mitochondrial 16S rRNA gene and the complete sequence of the nuclear 18S rRNA gene supported the description of A. hadanii as a new species.
Nava, S; Szabó, M P J; Mangold, A J; Guglielmone, A A
The hosts, distribution, intraspecific genetic variation and phylogenetic position of Amblyomma parvum (Acari: Ixodidae) have recently been re-assessed. Data on this tick's hosts and distribution were obtained not only from existing literature but also from unpublished records. Sequences of the ticks' mitochondrial 16S ribosomal DNA (rDNA) were used to evaluate genetic variation among specimens of A. parvum from different localities in Argentina and Brazil, and to explore the phylogenetic relationships between this tick and other Amblyomma species. Although several species of domestic and wild mammal act as hosts for adult A. parvum, most collected adults of this species have come from cattle and goats. Caviid rodents of the subfamily Caviinae appear to be the hosts for the immature stages. So far, A. parvum has been detected in 12 Neotropical biogeographical provinces (Chaco, Cerrado, Eastern Central America, Venezuelan Coast, Pantanal, Parana Forest, Caatinga, Chiapas, Venezuelan Llanos, Monte, Western Panamanian Isthmus, and Roraima) but the Chaco province has provided significantly more specimens than any other (P<0.0001). The 16S rDNA sequences showed just 0.0%-1.1% divergence among the Argentinean A. parvum investigated and no more than 0.2% divergence among the Brazilian specimens. The observed divergence between the Argentinean and Brazilian specimens was, however, greater (3.0%-3.7%). Although there is now molecular and morphological evidence to indicate that A. parvum, A. pseudoparvum, A. auricularium and A. pseudoconcolor are members of a natural group, previous subgeneric classifications do not reflect this grouping. The subgeneric status of these tick species therefore needs to be re-evaluated. The 16S-rDNA-based evaluation of divergence indicates that the gene flow between Argentinean and Brazilian 'A. parvum' is very limited and that the Argentinean 'A. parvum' may be a different species to the Brazilian.
Carmichael, Joseph A; Strauss, Richard E; McIntyre, Nancy E
The ectoparasites of a small mammal community within an intertidal zone in the upper Gulf coast region of Texas were studied to assess the seasonal variation in abundances of the mite Gigantolaelaps mattogrossensis (Fonseca) (Acari: Laelapidae) on the marsh rice rat, Oryzomys palustris (Harlan). Further study into the ecology and dynamics of this parasite-host relationship was deemed to be necessary to expand the understanding of these potential participants in the ecology of Bayou Hantavirus, an important causative agent of Hantavirus pulmonary syndrome. The objective of this study was to determine the effects of five predictor variables on mite abundance: prevalences of hosts, relative humidity, precipitation, temperature, and length of daylight. Mite abundance was modeled as a function of the five variables with analyses of variance and multiple regressions; however, because the predictor variables pertain to the sampling period rather than to the individual rodent host, the effective sample size was small and thus the sums of squares and cross products matrix was singular. We therefore developed and used a new method for estimating regression coefficients based on the "noise-addition method" (random residual variation) combined with a bootstrap step converting the reduced rank data to full rank, providing realistic estimates of confidence intervals for the regression statistics. The population abundances of mites fluctuated significantly across collecting periods. Humidity and precipitation were the most influential variables in explaining the variation in abundances of mites. Model interpretation suggests that G. mattogrossensis is a nidicolous parasite. These results provide a baseline understanding of the seasonal interactions between parasite and host.
Yunik, Matthew E.M.; Galloway, Terry D.; Lindsay, L. Robbin
Bovine anaplasmosis is the disease caused by the bacterium Anaplasma marginale. It can cause production loss and death in cattle and bison. This was a reportable disease in Canada until April 2014. Before then, infected herds were quarantined and culled, removing infected animals. In North America, A. marginale is biologically vectored by hard ticks (Acari: Ixodidae), Dermacentor variabilis and D. andersoni. Biting flies, particularly horse flies (Diptera: Tabanidae), can also act as mechanical vectors. An outbreak of bovine anaplasmosis, consisting of 14 herds, was detected in southern Manitoba in 2008. This outbreak lasted multiple rounds of testing and culling before eradication in 2011, suggesting local maintenance of the pathogen was occurring. We applied novel approaches to examine the vector ecology of this disease in this region. We did not detect A. marginale by screening of 2056 D. variabilis (2011 and 2012) and 520 horse flies (2011) using polymerase chain reaction (PCR). PMID:27127345
Apanaskevich, Dmitry A
Recent reexamination of collection lots stored in the United States National Tick Collection revealed adult specimens of Dermacentor compactus Neumann, 1901 (Acari: Ixodidae) reared from field-collected nymphs, which allowed us to associate field-collected unidentified nymphs and larvae with this species. Nymphs of D. compactus can be easily distinguished from those of other congeneric species by the shape of the scutum and spiracular plate, the hypostome dentition, and the size of the spurs on the coxae. Larvae of this species can be distinguished by the shape and sculpture of the scutum, the shape of basis capituli, the absence of auriculae, and the size of the spurs on coxae II and III. Both nymphs and larvae feed mostly on various species of squirrels (Rodentia: Sciuridae). Considerably fewer nymphs and larvae were found on murid rodents (Rodentia: Muridae), domestic dogs (Carnivora: Canidae), and a snake (Squamata: Colubridae).
Dowling, Ashley P G; Bochkov, Andre V; O'Connor, Barry M
The mesostigmatid genus Andreacarus Radford, 1953 (Acari: Laelapidae), species of which are obligatory parasites of small mammals, is revised. Andreacarus includes 11 species, four species previously recognized and seven new species described from Madagascar hosts: A. brachyuromys sp. n. from Brachyuromys betsileoensis Bartlett, A. eliurus sp. n. from Eliurus species, A. gymnuromys sp. n. from Gymnuromys roberti Major, A. voalavo sp. n. from Voalavo gymnocaudus Carleton & Goodman, A. nesomys sp. n. from Nesomys rufus Peters-all from nesomyid rodents; A. tenrec sp. n. from Tenrec ecaudatus Schreber (Afrosoricida: Tenrecidae); and A. galidia from Galidia elegans I. Geoffroy Saint-Hilaire (Carnivora: Viverridae). An amended generic diagnosis and key to females are also given. Six species described in Andreacarus from Australian and New Guinean hosts are removed and transferred to the new genus, Juxtalaelaps.
Koc, Samed; Oz, Emre; Cinbilgel, Ilker; Aydin, Levent; Cetin, Huseyin
The acaricidal activity of an essential oil obtained from aerial parts of Origanum bilgeri P.H. Davis (Lamiaceae), an endemic species in Turkey, and its major constituents, carvacrol was evaluated against unfed adults Rhipicephalus turanicus Pomerantzev (Acari: Ixodidae) collected from Kepez, Antalya. The composition of the essential oil was analyzed by GC/MS. The major compound identified in the oil was carvacrol (93.02%). Generally, tick mortalities to the O. bilgeri distillate and carvacrol increased with concentrations. O. bilgeri oil produced >83% mortality at 48h at a concentration of 0.8% and mortality was higher than 63% at a carvacrol concentration of 0.4%. Our results have shown that O. bilgeri essential oil and its major component, carvacrol, may have potential as acaricidal agents against R. turanicus.
Yunik, Matthew E M; Galloway, Terry D; Lindsay, L Robbin
Bovine anaplasmosis is the disease caused by the bacterium Anaplasma marginale. It can cause production loss and death in cattle and bison. This was a reportable disease in Canada until April 2014. Before then, infected herds were quarantined and culled, removing infected animals. In North America, A. marginale is biologically vectored by hard ticks (Acari: Ixodidae), Dermacentor variabilis and D. andersoni. Biting flies, particularly horse flies (Diptera: Tabanidae), can also act as mechanical vectors. An outbreak of bovine anaplasmosis, consisting of 14 herds, was detected in southern Manitoba in 2008. This outbreak lasted multiple rounds of testing and culling before eradication in 2011, suggesting local maintenance of the pathogen was occurring. We applied novel approaches to examine the vector ecology of this disease in this region. We did not detect A. marginale by screening of 2056 D. variabilis (2011 and 2012) and 520 horse flies (2011) using polymerase chain reaction (PCR).
Silva, Camila de Lima; Graciolli, Gustavo
Acari ectoparasites were collected from bats during 12 months in the Rio Negro farm (19°34'22″S and 56°14'36″W), Aquidauana, Mato Grosso do Sul. A total of 654 bats belonging to the families Phyllostomidae, Noctilionidae, Molossidae, Vespertilionidae and Emballonuridae were captured. Only 136 bats of nine genera and 11 species were parasitised. Periglischrus iheringi Oudemans was the most abundant mite species, and this prevalence may be related to the low degree of host specificity of this species and due to the broad geographical distribution of its hosts. The greatest mean intensity was found to Periglischrus torrealbai Machado-Allison on Phyllostomus discolor Wagner (Phyllostomidae) and Periglischrus tonatii Herrin and Tipton associated with Lophostoma silviculum d'Orbigny (Phyllostomidae), which also had the highest prevalence of infestation.
Lawson-Balagbo, L M; Gondim, M G C; de Moraes, G J; Hanna, R; Schausberger, P
Coconut is an important crop in tropical and subtropical regions. Among the mites that infest coconut palms, Aceria guerreronis Keifer is economically the most important. We conducted surveys throughout the coconut growing areas of Brazil. Samples were taken from attached coconuts, leaflets, fallen coconuts and inflorescences of coconut palms in 112 localities aiming to determine the occurrence and the distribution of phytophagous mites, particularly A. guerreronis, and associated natural enemies. Aceria guerreronis was the most abundant phytophagous mite followed by Steneotarsonemus concavuscutum Lofego & Gondim Jr. and Steneotarsonemus furcatus De Leon (Tarsonemidae). Infestation by A. guerreronis was recorded in 87% of the visited localities. About 81% of all predatory mites belonged to the family Phytoseiidae, mainly represented by Neoseiulus paspalivorus De Leon, Neoseiulus baraki Athias-Henriot and Amblyseius largoensis Muma; 12% were Ascidae, mainly Proctolaelaps bickleyi Bram, Proctolaelaps sp nov and Lasioseius subterraneus Chant. Neoseiulus paspalivorus and N. baraki were the most abundant predators on attached coconuts. Ascidae were predominant on fallen coconuts, while A. largoensis was predominant on leaflets; no mites were found on branches of inflorescences. Leaflets harboured higher mite diversity than the attached coconuts. Mite diversity was the highest in the state Pará and on palms surrounded by seasonal forests and Amazonian rain-forests. Neoseiulus paspalivorus, N. baraki and P. bickleyi were identified as the most promising predators of A. guerreronis. Analyses of the influence of climatic factors revealed that dry ambient conditions favour the establishment of A. guerreronis. Neoseiulus paspalivorus and N. baraki have differing climatic requirements; the former being more abundant in warm and dry areas, the latter prevailing in moderately tempered and humid areas. We discuss the significance of our findings for natural and biological
Luo, Jin; Liu, Guang-Yuan; Chen, Ze; Ren, Qiao-Yun; Yin, Hong; Luo, Jian-Xun; Wang, Hui
Hyalomma anatolicum anatolicum (H.a. anatolicum) (Acari: Ixodidae) ticks are globally distributed ectoparasites with veterinary and medical importance. These ticks not only weaken animals by sucking their blood but also transmit different species of parasitic protozoans. Multiple factors influence these parasitic infections including miRNAs, which are non-coding, small regulatory RNA molecules essential for the complex life cycle of parasites. To identify and characterize miRNAs in H.a. anatolicum, we developed an integrative approach combining deep sequencing, bioinformatics and real-time PCR analysis. Here we report the use of this approach to identify miRNA expression, family distribution, and nucleotide characteristics, and discovered novel miRNAs in H.a. anatolicum. The result showed that miR-1-3p, miR-275-3p, and miR-92a were expressed abundantly. There was a strong bias on miRNA, family members, and nucleotide compositions at certain positions in H.a. anatolicum miRNA. Uracil was the dominant nucleotide, particularly at positions 1, 6, 16, and 18, which were located approximately at the beginning, middle, and end of conserved miRNAs. Analysis of the conserved miRNAs indicated that miRNAs in H.a. anatolicum were concentrated along three diverse phylogenetic branches of bilaterians, insects and coelomates. Two possible roles for the use of miRNA in H.a. anatolicum could be presumed based on its parasitic life cycle: to maintain a large category of miRNA families of different animals, and/or to preserve stringent conserved seed regions with active changes in other places of miRNAs mainly in the middle and the end regions. These might help the parasite to undergo its complex life style in different hosts and adapt more readily to the host changes. The present study represents the first large scale characterization of H.a. anatolicum miRNAs, which could further the understanding of the complex biology of this zoonotic parasite, as well as initiate miRNA studies
Ahn, Jeong Joon; Son, Youngsoo; He, Yaqian; Lee, Eungul; Park, Yong-Lak
Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, were determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. The findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed. *Scientific Article No. 3278 of the West Virginia Agricultural and Forestry Experiment Station, Morgantown, West Virginia PMID
Gazim, Zilda Cristiani; Demarchi, Izabel Galhardo; Lonardoni, Maria Valdrinez Campana; Amorim, Ana Carolina L; Hovell, Ana Maria C; Rezende, Claudia Moraes; Ferreira, Gilberto Alves; de Lima, Edson Luiz; de Cosmo, Fábio Antunes; Cortez, Diogenes Aparício Garcia
Tetradenia riparia (Lamiaceae) is a well-known herbal medicine with a variety of useful properties, including its acaricidal effect. This experiment was carried out to study the bioacaricidal activity of T. riparia essential oil (EO) against engorged females of Rhipicephalus (Boophilus) microplus (Acari; Ixodidae). For this purpose, nine serial concentrations (12.50%, 6.25%, 3.75%, 1.80%, 0.90%, 0.45%, 0.22%, 0.11%, and 0.056% w/v) of T. riparia were used for the adult immersion test (AIT). For the larval packet test (LPT), we used 14 serial concentrations (100.00%, 50.00%, 25.00%, 12.50%, 6.25%, 3.65%, 1.82%, 0.91%, 0.45%, 0.228%, 0.114%, 0.057%, 0.028%, and 0.014% w/v). The results for AIT showed 100.00% and 2.05% mortality, 19.00 and 90.20% for the total number of eggs, egg-laying inhibition of 0.00% and 90.20%, hatchability inhibition of 0.00% and 70.23%, and product effectiveness of 100.00% and 2.89%, respectively. The AIT indicated that the LC(50) and LC(99.9), calculated using the Probit test, were for mortality (%) 0.534g/mL (0.436-0.632) and 1.552g/mL (1.183-1.92); for total number of eggs were 0.449g/mL (0.339-0.558) and 1.76g/mL (1.27-2.248); and for hatchability inhibition were 0.114g/mL (0.0-0.31) and 2.462g/mL (1.501-3.422), respectively. Larvae between 14 and 21days old were fasted and placed in each envelope. Bioassays were performed at 27°±1°C, RH⩾80%. Larval mortality was observed 24h after treatment and showed 10.60-100% mortality in the LPT bioassay. The LPT showed that the LC(50) and LC(99.9) were 1.222g/mL (0.655-1.788) and 11.382g/mL (7.84-14.91), respectively. A positive correlation between T. riparia EO concentration and tick control, was observed by the strong acaricidal effects against R. (B.) microplus, and the mortality rate of ticks was dose-dependent. Our results showed that T. riparia is a promising candidate as an acaricide against resistant strains of R. (B.) microplus.
Ahn, Jeong Joon; Son, Youngsoo; He, Yaqian; ...
Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, weremore » determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. Lastly, the findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed.« less
[Ocurrence of Ornithonyssus bursa (Berlese, 1888) (Acari: Macronyssidae) on Megascops choliba (tropical screech-owl) and Pitangus sulphuratus (great kiskadee) nestlings in the Rio Grande do Sul State, Brazil].
Mascarenhas, Carolina S; Coimbra, Marco A A; Müller, Gertrud; Brum, João Guilherme W
The Center for Rehabilitation of Wildlife and Center for Selection of Wild Animal of the Federal University of Pelotas has attended two nestlings of Megascops choliba (tropical screech-owl) (Strigiformes - Strigidae) and two of Pitangus sulphuratus (great kiskadee) (Passeriformes - Tyrannidae) heavily parasitized by mites, in May 2005 and December 2006, respectively. The nestlings and the nest of P. sulphuratus were collected in the Pelotas urban area after severe storms. The mites were removed, clarified in lactofenol, permanently mounted in Hoyer's medium and identified as Ornithonyssus bursa (Acari - Macronyssidae). Megascops choliba and Pitangus sulphuratus are reported as host of Ornithonyssus bursa in Rio Grande do Sul State, Brazil.
Yang, Banghe; Li, Chaopin
Mites of the genus Tyrophagus are economically important polyphagous pest commonly living on stored products and also responsible for allergic reactions to humans. Complete mitochondrial genomes (mitogenomes) and the gene features therein are widely used as molecular markers in the study of population genetics, phylogenetics as well as molecular evolution. However, scarcity on the sequence data has greatly impeded the studies in these areas pertaining to the Acari (mites and ticks). Information on the Tyrophagus mitogenomes is quite critical for phylogenetic evaluation and molecular evolution of the mitogenomes within Acariformes. Herein, we reported the complete mitogenome of the allergenic acarid storage mite Tyrophagus longior (Astigmata: Acaridae), an important member of stored food pests, and compared with those of other three acarid mites. The complete mitogenome of T. longior was a circular molecule of 13,271 bp. Unexpectedly, only 19 transfer RNA genes (tRNAs) were present, lacking trnF, trnS1 and trnQ. Furthermore, it also contained 13 protein-coding genes (PCGs) and 2 genes for rRNA (rrnS and rrnL) commonly detected in metazoans. The four mitogenomes displayed similar characteristics with respect to the gene content, nucleotide comparison, and codon usages. Yet, the gene order of T. longior was different from that in other Acari. The J-strands of the four mitogenomes possessed high A+T content (67.4-70.0%), and exhibited positive GC-skews and negative AT-skews. Most inferred tRNAs of T. longior were extremely truncated, lacking either a D- or T-arm, as found in other acarid mites. In T. longior mitogenome the A+T-rich region was just 50 bp in length and can be folded as a stable stem-loop structure, whereas in the region some structures of microsatellite-like (AT)n and palindromic sequences was not present. Besides, reconstructing of the phylogenetic relationship based on concatenated amino acid sequences of 13 PCGs supported that monophyly of the family
Bochkov, A V; Fain, A
A new myobiid species Radfordia (Hesperomyobia) sigmomys sp. n. (Acari: Myobiidae) ex Sigmodon alstoni (Rodentia: Sigmodontidae) from Central America is described. This description is based from the females, proto-, dueto- and tritonymphs. Female (4 spec.). Body 500-510 (in micrometers) long and 295-320 wide. Length of setae: ve 90-95--widely lanceolate, 10-15; vi 23-25, sci 95-105, sce 90-100, d1 80-85, d2 70-90, d3 20-25, d4 23-27, l1 75-90, l2 80-85, l3 25-27--all narrowly lanceolate; d5 10-15, l4 10-15, ic1 25-30, ic2 80-90, ic3 85-90, ic4 15-18, pg1 10-15, pg2 30-40, pg3 8-10--all hair-like. Protonymph (2 spec.). Idiosoma with 14 pairs of dorsal setae, including el and 2 pairs of very short anal setae, and 4 pairs of ventral setae, including l5. Length of setae: vi 25, ve 23-25, sci 50-52, sce 125-130, d1 18, d2 16, d3 10-12, l1 10-15, l2 12-16, l3 10-13--all lanceolate; d4 6, ic1 l1, ic2 25-27, ic3 15--all hair-like. Leg chaetotaxy II-III: II coxa 0--trochanter 0--genu + femur 2 (1 solenidion)--tibia 4--tarsus 7 (1 solenidion), III 0-0-0-3-6. Deutonymph (2 spec.). Setae 14 added. Length of setae: vi 25-27, ve 30-35, sci 65-70, sce 120-155, d1 20, d2 16-18, d3 11-13, d4 10-13, l1 20-27, l2 10-15, l3 l1--all lanceolate; l4 6, ic1 13-15, ic2 35-40, ic3 25--all hair-like. Leg chaetotaxy II-III: II 0-0-3(1)-4-7(1), III 0-0-1-3-6. Tritonymph (2 spec.). Setae d5 and ic4 added. Length of setae: vi 34(35), ve 45(40), sci 80(75), sce 140(150), d1 23(25), d2 25(25), d3 13(10), d4 13(10), l1 100(90), l2 22(25), l3 25(27)--all lanceolate; l4 6(5), d5 4(5), ic1 12(15), ic2 45(50), ic3 35(40)--all hair-like; setae 14 microchaetae. Leg chaetotaxy II-IV: II 1-1-3(1)-4-7(1), III 0-1-1-3-6, IV 0-0-1-3-4. This new species is closely related to R. (H). sigmodontis Radford, 1951 ex Sigmodon hispidus from USA. The females of these two species are not distinguishable from each other. While the tritonymphs differ by the following characters. In R. (H.) sigmomys sp. n., the length of
Abstract The family Tetranychidae (spider mites) currently comprises 1,275 species and represents one of the most important agricultural pest families among the Acari with approximately one hundred pest species, ten of which considered major pests. The dataset presented in this document includes all the identified spider mites composing the Jean Gutierrez Collection hosted at the CBGP (Montferrier-sur-Lez, France), gathered from 1963 to 1999 during his career at the Institut de Recherche pour le Développement (IRD). It consists of 5,262 specimens corresponding to 1,564 occurrences (combination species/host plant/date/location) of 175 species. Most specimens were collected in Madagascar and other islands of the Western Indian Ocean, New Caledonia and other islands of the South Pacific and Papuasia. The dataset constitutes today the most important one available on Tetranychidae worldwide. PMID:25878529
Skoracki, Maciej; Unsoeld, Markus; Marciniak, Natalia; Sikora, Bozena
The quill mite fauna of the family Syringophilidae (Acari: Prostigmata: Cheyletoidea) associated with owls (Aves: Strigiformes) is reviewed. A new genus is proposed, Neobubophilus Skoracki & Unsoeld gen. nov. It differs from closely related Bubophilus (Bubophilus Philips and Norton, 1978) by the absence of leg setae vsII in the both sexes. In addition, four new species are described: (1) Neobubophilus cunicularius Skoracki & Unsoeld sp. nov. from Athene cunicularia (Molina, 1782) (Strigidae) from Paraguay; (2) Neobubophilus atheneus Skoracki & Unsoeld sp. nov. from Athene noctua (Scopoli, 1769) and Athene brama (Temminck, 1821) (Strigidae), both from India; (3) Bubophilus tytonus Skoracki & Unsoeld sp. nov. from Tyto alba affinis (Blyth, 1862) (Tytonidae) from Cameroon, and (4) Megasyringophilus dalmas Skoracki & Unsoeld sp. nov. from Megascops choliba (Vieillot, 1817) (Strigidae) from Venezuela. The following new host species are given: Bubo bubo (Linnaeus, 1758) (Strigidae) from Nepal for Bubophilus ascalaphus (Philips and Norton 1978) and Strix woodfordii (Smith, 1834) (Strigidae) from Tanzania for Bubophilus aluconis (aluconis Nattress and Skoracki 2009). A key for syringophilid genera and species associated with owls is constructed. The host-parasite relationships of syringophilid mites and owls are discussed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com Version of Record, first published online May 24, 2016 with fixed content and layout in compliance with Art. 22.214.171.124 ICZN.
Blanco, Carolina Moreira; Teixeira, Bernardo Rodrigues; da Silva, Alexandro Guterres; de Oliveira, Renata Carvalho; Strecht, Liana; Ogrzewalska, Maria; de Lemos, Elba Regina S
Information about tick fauna and monitoring of pathogen prevalences in ticks (Acari: Ixodidae) in various habitat types can enhance knowledge about the epidemiology of tick-borne pathogens in Brazil. This work shows the results of a study of tick parasitism of wild rodents and marsupials collected in seven localities in the southern part of Brazil, within Atlantic Forest and Cerrado biomes. A total of 61 ticks were collected from small mammals, and after identification to the species level, the ticks were individually tested for the presence of bacteria of the genera Rickettsia, Borrelia, family Anaplasmataceae, and protozoa of the genus Babesia. The following species of ticks were found: Amblyomma ovale Koch, 1844, Amblyomma dubitatum Neumann, 1899, Amblyomma fuscum Neumann, 1907, Ixodes aragaoi Fonseca, 1935, Ixodes fuscipes Koch, 1844, Ixodes loricatus Neumann, 1899, and Ixodes schulzei Aragão and Fonseca, 1951. Among tested ticks, no DNA of Borrelia, Babesia or Anaplasmataceae was detected. Two nymphs of A. ovale were found infected with Rickettsia bellii and four nymphs of I. aragaoi with Rickettsia sp., genetically close to Rickettsia monacensis, Rickettsia tamurae and the endosymbiont Rickettsia spp., previously found in various Ixodidae. In one nymph of A. fuscum, DNA of a novel Hepatozoon sp. was found. Additionally we provide novel tick-host associations.
Swei, A; Meentemeyer, R; Briggs, C J
The abiotic and biotic factors that govern the spatial distribution of Lyme disease vectors are poorly understood. This study addressed the influence of abiotic and biotic environmental variables on Ixodes pacificus Cooley & Kohls (Acari:Ixodidae) nymphs, because it is the primary vector of Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwaldt & Brenner in the far-western United States. Three metrics of Lyme disease risk were evaluated: the density of nymphs, the density of infected nymphs, and the nymphal infection prevalence. This study sampled randomly located plots in oak (Quercus spp.) woodland habitat in Sonoma County, CA. Each plot was drag-sampled for nymphal ticks and tested for B. burgdorferi infection. Path analysis was used to evaluate the direct and indirect relationship between topographic, forest structure and microclimatic variables on ticks. Significant negative correlations were found between maximum temperature in the dry season and the density of infected ticks in 2006 and tick density in 2007, but we did not find a significant relationship with nymphal infection prevalence in either year. Tick density and infected tick density had an indirect, positive correlation with elevation, mediated through temperature. This study found that in certain years but not others, temperature maxima in the dry season may constrain the density and density of infected I. pacificus nymphs. In other years, biotic or stochastic factors may play a more important role in determining tick density.
Banajee, K. H.; Verhoeve, V. I.; Harris, E. K.; Macaluso, K. R.
Rickettsia parkeri Luckman (Rickettsiales: Rickettsiaceae) is a pathogenic spotted fever group Rickettsia transmitted by Amblyomma maculatum Koch (Acari: Ixodidae) in the United States. The acute innate immune response to this pathogen and the effect of tick feeding or salivary components on this response is largely unknown. We hypothesized that A. maculatum saliva enhances R. parkeri infection via downregulation of the acute cellular and cytokine immune response. C3H/HeN mice were intradermally inoculated with R. parkeri both with and without A. maculatum saliva. Flow cytometry and microscopic evaluation of inoculation site skin suspensions revealed that neutrophils and macrophages predominated at 6 and 24 h post R. parkeri inoculation, respectively. This cellular influx was significantly downregulated when A. maculatum saliva was inoculated along with R. parkeri. Inflammatory cytokines (interferon γ and interleukins 6 and 10) were significantly elevated after R. parkeri inoculation. However, cytokine concentration and rickettsial load were not significantly modified by A. maculatum saliva during the acute phase of infection. These results revealed that tick saliva inhibits the cutaneous cellular influx during the acute phase of rickettsial infection. Further study is needed to determine the overall impact of this effect on the establishment of rickettsiosis in the host and development of disease. PMID:27521760
Yu, Zhijun; Thomson, Euan L S; Liu, Jingze; Dennis, Jonathan J; Jacobs, René L; Kaufman, W Reuben
Untreated eggs of the tick Amblyomma hebraeum Koch (Acari: Ixodidae) exhibited antimicrobial activity (AMA) against Gram-negative but not Gram-positive bacteria; eggs denuded of wax by solvent extraction showed no AMA. The unfractionated egg wax extract, however, showed AMA against Gram-positive but not Gram-negative bacteria, as also shown by Arrieta et al. (Exp Appl Acarol 39: 297-313, 2006). In this study we partitioned the egg wax into various fractions, using a variety of techniques, analyzed their compositions, and tested them for AMA. The crude aqueous extract exhibited AMA. However, although more than 30 metabolites were identified in this extract by nuclear magnetic resonance analysis, none of them seemed likely to be responsible for the observed AMA. In the crude organic extract, cholesterol esters were the most abundant lipids, but were devoid of AMA. Fatty acids (FAs), with chain lengths between C13 and C26 were the next most abundant lipids. After lipid fractionation and gas chromatography/mass spectroscopy, free FAs, especially C16:1 and C18:2, accounted for most of the AMA in the organic extract. The material responsible for AMA in the crude aqueous extract remains unidentified. No AMA was detected in the intracellular contents of untreated eggs.
Campos, Roseane Nunes de Santana; Nascimento Lima, Cecília Beatriz; Passos Oliveira, Alexandre; Albano Araújo, Ana Paula; Fitzgerald Blank, Arie; Barreto Alves, Péricles; Nascimento Lima, Rafaely; Albano Araújo, Vinícius; Santana, Alisson Silva; Bacci, Leandro
Ticks are arthropods widely distributed in tropical and subtropical regions, which can transmit infectious agents also responsible for zoonoses. Excessive use of conventional acaricides has resulted in the onset of drug resistance by these parasites, thus the need to use alternative methods for their control. This study evaluated the acaricidal activities of Chrysopogon zizanioides (vetiver) essential oils containing different zizanoic and khuzimol (high and low acidity) acid concentrations on Amblyomma cajennense and Rhipicephalus microplus (Acari: Ixodidae). To this aims, toxicity tests of different concentrations of examined essential oils were conducted on adult females and larval stages. Results showed that the essential oils of C. zizanioides with high and low acidity reduced oviposition of females, eggs hatch and larval survival, being more effective than some commercial products widely used to control these ectoparasites. These results indicate that the C. zizanoides essential oils are promising candidates as acaricidal agents and represent also an add value to vetiver oil with high acidity, which is commercially undervalued in the cosmetic industry.
Skoracki, Maciej; Unsoeld, Markus; Skorupski, Maciej; Kavetska, Katarzyna
The fauna of quill mites of the family Syringophilidae Lavoipierre, 1953 (Acari: Prostigmata Cheyletoidea) parasitising birds of the family Rallidae Vigors (Gruiformes) is updated. A new species, Rafapicobia melzeri n. sp. (subfamily Picobiinae), is described from four host species: Rallus aquaticus Linnaeus (type-host) from Germany, Pardirallus sanguinolentus (Swainson) from Chile, Porzana porzana (Linnaeus) from France and P. parva (Scopoli) from Kirghizia. The new species is most similar to R. lepidocolaptesi Skoracki & Solarczyk, 2012 but differs in the absence of agenital plates and the length ratios of setae ag2:g1 and vi:ve:si in females and in the punctate ornament on the hysteronotal and the pygidial shields in males. A key to the species of the genus Rafapicobia is proposed. This is the first record of a representative of the subfamily Picobiinae on gruiform birds. Additionally, new rallid hosts are reported for Charadriphilus ralli Skoracki & Bochkov, 2010 (subfamily Syringophilinae): Gallinula melanops (Vieillot) from Chile, Laterallus melanophaius (Vieillot) from Paraguay, and P. parva (Scopoli) from Kirghizia.
Eamsobhana, Praphathip; Yoolek, Adisak; Kongkaew, Wittaya; Lerdthusnee, Kriangkrai; Khlaimanee, Nittaya; Parsartvit, Anchana; Malainual, Nat; Yong, Hoi-Sen
Scrub typhus, a rickettsial disease transmitted by several species of Leptotrombidium chiggers (larvae), is endemic in many areas of Asia. The disease is best prevented by the use of personal protective measures, including repellents. In this study commercially produced aromatic, essential oils of 13 plant species and ethanol (control) were tested in the laboratory for repellency against host-seeking chiggers of Leptotrombidium imphalum Vercammen-Grandjean and Langston (Acari: Trombiculidae). A rapid, simple and economic in vitro test method was used by exposing the chigger for up to 5 min. Repellency was based on relative percentages of chiggers attracted to test and control substances. Four of the 13 essential oils showed promise as effective repellent against L. imphalum chiggers. Syzygium aromaticum (clove) oil exhibited 100% repellency at 5% concentration (dilution with absolute ethanol), whereas Melaleuca alternifolia (tea tree) oil exhibited 100% repellency at 40% concentration. Undiluted oils of Zingiber cassamunar (plai) and Eucalyptus globules (blue gum) exhibited 100% repellency. Of the remaining nine essential oils, only 100% Pelargonium graveolens (geranium) exhibited >50% repellency (viz. 57%). Styrax torkinensis (benzoin) oil did not exhibit any repellency. These findings show that several aromatic, essential oils of plants may be useful as chigger repellent for the prevention of scrub typhus. Syzygium aromaticum oil may be safer and more economical to prevent chigger attacks than commercially available synthetic chemicals, such as DEET that may have harmful side effects.
Bochkov, Andre V; Skirnisson, Karl
A new species of syringophilid mites, Mironovia lagopus sp. nov. (Acari: Syringophilidae) is described from feather quills of the rock ptarigman Lagopus muta (Montin) (Phasianidae) from Iceland. Females of this new species differ from the closely related Mironovia rouloul Skoracki and Sikora by setae d2, which are subequal or 1.1-1.2 times shorter than setae e2 (vs. d2 1.4-1.5 times longer than e2 in Mironovia rouloul) and by setae ag1, which are 1.3-1.5 times shorter than ag2 (vs. ag1 1.7-1.8 times shorter than ag2). The postembryonic stages of this new species are figured and described in details. In ontogeny of Mironovia spp., the observed pattern of setal appearance is not different from the pattern in other galliform-associated genera such as Syringophilus and Colinophilus, with exception for tarsal setae p'I, II which are absent in protonymphs. The key to all four species of the genus Mironovia is also provided.
Schulze, Terry L; Jordan, Robert A; Healy, Sean P; Roegner, Vivien E; Meddis, Michael; Jahn, Margaret B; Guthrie, Douglas L
To evaluate their potential importance in the transmission of ixodid tick-borne borrelioses in Monmouth County, NJ, we collected host-seeking Ixodes scapularis Say and Amblyomma americanum (L.) (Acari: Ixodidae) adults and nymphs to determine relative encounter frequencies and the infection prevalence of selected Borrelia spp. in their respective tick vectors. We also reviewed records of all ticks submitted for identification by the public in Monmouth County during 2001-2005. Relative abundance of the two species varied markedly among sites. Adult encounter frequencies for the two species were similar; however, A. americanum nymphs were encountered 3 times more frequently than I. scapularis nymphs. Of 435 ticks submitted by the public, 50.1 and 38.9% were I. scapularis and A. americanum, respectively. However, during May through August, the peak Lyme disease transmission season in New Jersey, significantly more submitted ticks were A. americanum (55.9%), compared with I. scapularis (34.1%). Polymerase chain reaction analysis of 94 1. scapularis and 103 A. americanum adults yielded infection prevalences of 31.9% for B. burgdorferi and 5.8% for B. lonestari, respectively. Although the infection prevalence of B. burgdorferi in I. scapularis was considerably higher than the infection prevalence of B. lonestari in A. americanum, the higher encounter frequencies for A. americanum compared with I. scapularis observed in this and other studies may result in increased risk of acquiring exposure to A. americanum-transmitted pathogens. The potential public health implications of these results are discussed.
Guglielmone, Alberto A; Venzal, José M; González-Acuña, Daniel; Nava, Santiago; Hinojosa, Ana; Mangold, Atilio J
The female of Ixodes stilesi Neumann, 1911 (Acari Ixodidae) is redescribed and the male and nymph are described from specimens collected from Pudu puda (Molina) (Artiodactyla: Cervidae) in Chile. Both sexes of I. stilesi have characteristics of the subgenera Ixodes Latreille, 1795 and Ixodiopsis Filippova, 1957. The females of I. stilesi are peculiar in having the combination of the sinuous scutum outline, rounded porose areas with distinct borders separated by the width of one area, slender and long palpi, and two subequal spurs on coxa I. The male is unique in having a combination of a posteriorly wrinkled marginal folder, a basis capituli longer than wide, a non-crenulate hypostome toothed portion, two spurs on coxa II to IV and the presence of a pseudoscutum. The nymph of I. stilesi has blunt anterior and posterior processes on palpal article I (characteristics of the subgenus Ixodiopsis and some Pholeoixodes Schulze, 1942) and a wing-shaped basis capituli with a prominent triangular cornua. Phylogenetic analyses based on 16S mitochondrial rDNA sequences of 12 Neotropical and two Australian Ixodes species, plus three argasids, were carried out to clarify the position of I. stilesi. The results of phylogenetic analyses and morphological characters indicate a close relationships between I. stilesi and two other Neotropical species of uncertain subgeneric status, I. neuquenensis Ringuelet, 1947 and I. sigelos Keirans, Clifford & Corwin, 1976.
Huang, Li-Qin; Guo, Xian-Guo; Speakman, John R; Dong, Wen-Ge
During a survey lasting from 1990 to 2008, we captured 4,113 Asian house rats, Rattus tanezumi Temminck 1844 (Rodentia: Muridae) from 28 counties of Yunnan Province in southwestern China. From these rats, a total of 19,304 gamasid mites (Acari: Mesostigmata) were collected and identified as comprising 50 different species. The species diversity of gamasid mites from this single rat species is higher than that reported previously from multiple hosts within a given geographical region. Of the 50 mite species, 31 species belonged to ectoparasites and 19 species belonged to free-living mites. The species diversity of the mites from rats trapped outdoors was much higher than from rats trapped indoors. The parameter K from the negative binomial distribution was used to measure the spatial distribution patterns of the dominant mite species and revealed that all the mites had an aggregated distribution among the rat hosts. Most mite species showed a predominantly female-biased population structure with many more females than males.
Zhao, Ya-E; Wang, Zheng-Hang; Xu, Yang; Wu, Li-Ping; Hu, Li
According to base pairing, the rRNA folds into corresponding secondary structures, which contain additional phylogenetic information. On the basis of sequencing for complete rDNA sequences (18S, ITS1, 5.8S, ITS2 and 28S rDNA) of Demodex, we predicted the secondary structure of the complete rDNA sequence (18S, 5.8S, and 28S rDNA) of Demodex folliculorum, which was in concordance with that of the main arthropod lineages in past studies. And together with the sequence data from GenBank, we also predicted the secondary structures of divergent domains in SSU rRNA of 51 species and in LSU rRNA of 43 species from four superfamilies in Acari (Cheyletoidea, Tetranychoidea, Analgoidea and Ixodoidea). The multiple alignment among the four superfamilies in Acari showed that, insertions from Tetranychoidea SSU rRNA formed two newly proposed helixes, and helix c3-2b of LSU rRNA was absent in Demodex (Cheyletoidea) taxa. Generally speaking, LSU rRNA presented more remarkable differences than SSU rRNA did, mainly in D2, D3, D5, D7a, D7b, D8 and D10. Copyright © 2013 Elsevier Inc. All rights reserved.
Elias, Susan P; Lubelczyk, Charles B; Rand, Peter W; Lacombe, Eleanor H; Holman, Mary S; Smith, Robert P
We evaluated the relationships between forest understory structure and the abundance of questing adult and nymphal blacklegged ticks, Ixodes scapularis Say (Acari: Ixodidae), in three Maine towns endemic for Lyme disease, 2001-2003. In fragmented New England woodlands, over-abundant white-tailed deer, Odocoileus virginianus Zimmerman, overbrowse palatable species, allowing browse-resistant exotic-invasive species to replace native forest understory structures. We predicted there would be more ticks in plots dominated by exotic-invasive shrubs (such as Japanese barberry, Berberis thunbergii DC) than in plots dominated by native shrubs, ferns, or open understory. We assessed canopy composition and closure, tree basal area, litter composition, percentage of coverage and stem density of understory species, litter depth, soil moisture, and abundance of small mammals and white-tailed deer pellet groups. We used generalized linear mixed model analysis of covariance to determine the effect of understory structure on tick counts, controlling for continuous habitat and host covariates and adjusting for random spatial effects. There were twice as many adults and nearly twice as many nymphs in plots dominated by exotic-invasives than in plots dominated by native shrubs. Both adult and nymphal counts were lowest in open understory with coniferous litter. Adults were positively associated with increasing litter depth, medium soil moisture, and increasing abundance of white-footed deer mice, Peromyscus leucopus Rafinesque, and deer pellet group counts. Nymphs were positively associated with increasing litter depth, moderately wet soil, and mice. We concluded that deer browse-resistant exotic-invasive understory vegetation presented an elevated risk of human exposure to the vector tick of Lyme disease.
Responses of Ornithonyssus sylviarum (Acari: Macronyssidae) and Menacanthus stramineus (Phthiraptera: Menoponidae) to gradients of temperature, light, and humidity, with comments on microhabitat selection on chickens.
Halbritter, D A; Mullens, B A
Responses of the northern fowl mite (NFM), Ornithonyssus sylviarum (Canestrini & Fanzago) (Acari: Macronyssidae), and the chicken body louse (CBL), Menacanthus stramineus (Nitzsch) (Phthiraptera: Menoponidae), to variation in temperature, light, and humidity were assessed in bioassays. The location on a continuous thermal gradient at which each ectoparasite arrested was recorded and analyzed. NFM adults arrested at an average temperature of 30.09 +/- 0.34 degrees C. Adult CBL and first-instar CBL nymphs arrested at 33.69 +/- 0.20 degrees C and 34.99 +/- 0.26 degrees C, respectively. Groups of each ectoparasite were placed into clear glass vials (n = 10/vial) with one half shaded, and vials were exposed to three light levels, as follows: high (200 micromolm(-2)s(-1)), low (4 micromolm(-2)s(-1)), and nearly no light (0 micromolm(-2)s(-1)). The vial cap edges provided an opportunity to assess the interactive effect of light with harborage. NFM avoided light and sought harborage. In low light, the harborage preference overrode the tendency to avoid light. CBL avoided the harborage and showed a minimal preference for light. A four-level humidity gradient was established in two separate experimental arenas for NFM and CBL. Trials were run in ambient light (4 micromolm(-2)s(-1)) for the NFM and in nearly no light for the CBL. The NFM gradient used 38 +/- 2%, 54 +/- 7%, 73 +/- 3%, and 90 +/- 4% RH, whereas the CBL gradient used 42 +/- 5%, 48 +/- 7%, 63 +/- 4%, and 73 +/- 5% RH. NFM showed no humidity response in the walking bioassay, but the CBL settled at the lowest humidity level. Temperature and humidity on different hen body regions were related to the bioassay results and observed on-host ectoparasite distributions.
Jordan, Robert A; Schulze, Terry L; Jahn, Margaret B
We monitored the abundance of Ixodes scapularis Say (Acari: Ixodidae) and the Lyme disease incidence rate after the incremental removal of white-tailed deer, Odocoileus virginianus Zimmermann, within a suburban residential area to determine whether there was a measurable decrease in the abundance of ticks due to deer removal and whether the reduction in ticks resulted in a reduction in the incidence rate within the human population. After three seasons, the estimated deer population was reduced by 46.7%, from the 2002 postfawning estimate of 2,899 deer (45.6 deer per km2) to a 2005 estimate of 1,540 deer (24.3 deer per km2). There was no apparent effect of the deer culling program on numbers of questing I. scapularis subadults in the culling areas, and the overall numbers of host-seeking ticks in the culling areas seemed to increase in the second year of the program. The Lyme disease incidence rate generated by both passive and active surveillance systems showed no clear trend among years, and it did not seem to vary with declining deer density. Given the resources required to mount and maintain a community-based program of sufficient magnitude to effectively reduce vector tick density in ecologically open situations where there are few impediments to deer movement, it may be that deer reduction, although serving other community goals, is unlikely to be a primary means of tick control by itself. However, in concert with other tick control interventions, such programs may provide one aspect of a successful community effort to reduce the abundance of vector ticks.
Nchu, Felix; Magano, Solomon R; Eloff, Jacobus N
Dichloromethane (DCM) extract of garlic (Allium sativum Linn.) bulbs was assessed for its repellent effect against the hard tick, Hyalomma rufipes (Acari: Ixodidae) using two tick behavioural bioassays; Type A and Type B repellency bioassays, under laboratory conditions. These bioassays exploit the questing behaviour of H. rufipes, a tick that in nature displays ambush strategy, seeking its host by climbing up on vegetation and attaching to a passing host. One hundred microlitres (100 µL) of the test solution containing DCM extract of garlic bulbs and DCM at concentrations of 0.35%, 0.7% or 1.4% w/v were evaluated. DCM only was used for control. Tick repellency increased significantly (R2 = 0.98) with increasing concentration (40.03% - 86.96%) yielding an EC50 of 0.45% w/v in Type B repellency bioassay. At concentration of 1.4% w/v, the DCM extract of garlic bulbs produced high repellency index of 87% (male ticks) and 87.5% (female ticks) in the Type A repellency bioassay. Only 4% avoidance of male ticks or female ticks was recorded in the Type B repellency bioassay. In the corresponding controls, the mean numbers of non-repelled male or female ticks were 80% and 41 males or 38 females of 50 ticks in the Type A and Type B repellency bioassays, respectively. The variations in the results could be attributed to the difference in tick repellent behaviours that were assessed by the two repellency bioassays; the Type A repellency bioassay assessed repellent effect of garlic extracts without discriminating between deterrence and avoidance whereas the Type B repellency bioassay only assessed avoidance response. Generally, DCM extract of garlic was repellent against H. rufipes, albeit weak tick repellency was obtained in the Type B repellency bioassay. Furthermore, this study established that the tick repellent activity of garlic extracts is predominantly by deterrence.
Meikle, W G; Mercadier, G; Holst, N; Nansen, C; Girod, V
A strain of the fungus Beauveria bassiana (Balsamo) Vuillemin (Deuteromycota: Hyphomycetes) isolated from varroa mites, Varroa destructor Anderson & Trueman (Acari: Varroidae), was used to treat honey bees, Apis mellifera L. (Hymenoptera: Apidae), against varroa mites in southern France. Fungal treatment caused a significant increase in the percentage of infected varroa mites compared with control treatments in two field experiments. In the first experiment, hives were treated with a formulation containing 0.37 g of B. bassiana conidia per hive and in the second experiment with a dose of 1.0 g of conidia per hive. The percentage of infected varroa mites also increased in the nontreated (control) hives, suggesting a movement of conidia, probably via bee drift, among the hives. Mite fall was significantly higher among treated hives compared with control hives on the sixth and eighth days after treatment in the first experiment. These days correspond to previously published data on the median survivorship of mites exposed to that fungal solate. The interaction of treatment and date was significant in the second experiment with respect to mite fall. Increases in colony-forming unit (cfu) density per bee were observed in all treatments but were significantly higher among bees from treated hives than control hives for at least a week after treatment. The relationship between cfu density per bee and proportion infected was modeled using a sigmoid curve. High levels of infection (>80%) were observed for cfu density per bee as low as 5 x 102 per bee, but the cfu density in hives treated with 0.37 g generally dropped below this level less than a week after treatment.
Description of a new species of Ixodes Latreille, 1795 (Acari: Ixodidae) and redescription of I. lasallei Méndez & Ortiz, 1958, parasites of agoutis and pacas (Rodentia: Dasyproctidae, Cuniculidae) in Central and South America.
Apanaskevich, Dmitry A; Bermúdez, Sergio E
Ixodes bocatorensis n. sp. (Acari: Ixodidae), is described based on adults ex agoutis (Rodentia: Dasyproctidae), pacas (Rodentia: Cuniculidae) and "tapir and sloth" (Perissodactyla: Tapiridae and Pilosa) from Colombia, Panama and Venezuela. Adults of I. bocatorensis n. sp. are similar to those of I. lasallei Méndez & Ortiz, 1958 but can be distinguished by the scutum dimensions, punctation pattern, gnathosoma and palpi measurements and their ratios, basis capituli anterior angle and shape of the spur of palpal segment I ventrally. For comparative purposes the female of I. lasallei is redescribed and the true male of this species is described for the first time. Studied adults of I. lasallei were found on agoutis, pacas and ocelot (Carnivora: Felidae) in Colombia, Peru and Venezuela.
First description of the male and redescription of the female of Ixodes tapirus Kohls, 1956 (Acari: Ixodidae), a parasite of tapirs (Perissodactyla: Tapiridae) from the mountains of Colombia, Costa Rica and Panama.
Apanaskevich, Dmitry A; Domínguez, Lillian G; Torres, Sugeys S; Bernal, Juan A; Montenegro, Victor M; Bermúdez, Sergio E
The male of Ixodes tapirus Kohls, 1956 (Acari: Ixodidae) is described for the first time and the female is redescribed in greater detail. Adults of I. tapirus are similar to those of Ixodes guatemalensis Kohls, 1956, Ixodes lasallei Méndez & Ortiz, 1958, Ixodes montoyanus Cooley, 1944 and Ixodes venezuelensis Kohls, 1953 but can be distinguished by their overall size, the amount of sclerotisation of the conscutum and accessory plates, the shape of the scutum, the number of punctations and their pattern on the conscutum and scutum, the depth of the punctations on the basis capituli dorsally, the shape and size of the porose areas and the size and shape of the auriculae. Adults of I. tapirus were collected from tapirs and vegetation in the mountains of Colombia, Panama and recorded from Costa Rica for the first time.
Navajas, M; Fenton, B
The application of molecular markers to the study of ticks and mites has recently yielded new insights into their population structures and taxonomic relationships. Ticks have been studied at individual, population and species level. Mites are a more diverse group and those that have been studied to the same degree as the ticks include the Tetranychidae (spider mites), Phytoseiidae (predatory mites) and the Eriophyidae. Population variation has also been studied in the important bee parasitic mite Varroa jacobsoni Oudemans. The methods used to study these organisms have much in common. At the individual level these range from general approaches, such as AFLP, RAPD or DALP, to highly specific microsatellite analysis. Although these markers also work at the population and species level, additional analysis of specific nuclear or mitochondrial genes has been conducted either by RFLP or sequencing. Molecular applications have had particular success in facilitating the identification of taxonomically difficult species, understanding population structures and elucidating phylogenetic relationships.
Ahn, Jeong Joon; Son, Youngsoo; He, Yaqian; Lee, Eungul; Park, Yong -Lak; Guedes, Raul Narciso Carvalho
Temperature plays an important role in the growth and development of arthropods, and thus the current trend of climate change will alter their biology and species distribution. We used Chaetodactylus krombeini (Acari: Chaetodactylidae), a cleptoparasitic mite associated with Osmia bees (Hymenoptera: Megachilidae), as a model organism to investigate how temperature affects the development and voltinism of C. krombeini in the eastern United States. The effects of temperature on the stage-specific development of C. krombeini were determined at seven constant temperatures (16.1, 20.2, 24.1, 27.5, 30.0, 32.4 and 37.8°C). Parameters for stage-specific development, such as threshold temperatures and thermal constant, were determined by using empirical models. Results of this study showed that C. krombeini eggs developed successfully to adult at all temperatures tested except 37.8°C. The nonlinear and linear empirical models were applied to describe quantitatively the relationship between temperature and development of each C. krombeini stage. The nonlinear Lactin model estimated optimal temperatures as 31.4, 32.9, 32.6 and 32.5°C for egg, larva, nymph, and egg to adult, respectively. In the linear model, the lower threshold temperatures were estimated to be 9.9, 14.7, 13.0 and 12.4°C for egg, larva, nymph, and egg to adult, respectively. The thermal constant for each stage completion were 61.5, 28.1, 64.8 and 171.1 degree days for egg, larva, nymph, and egg to adult, respectively. Under the future climate scenarios, the number of generations (i.e., voltinism) would increase more likely by 1.5 to 2.0 times by the year of 2100 according to simulation. Lastly, the findings herein firstly provided comprehensive data on thermal development of C. krombeini and implications for the management of C. krombeini populations under global warming were discussed.
Childers, Carl C; Ueckermann, Eduard A
Seven citrus orchards on reduced- to no-pesticide spray programs were sampled for predacious mites in the families Eupalopsellidae and Stigmaeidae (Acari: Prostigmata) in central and south central Florida. Inner and outer canopy leaves, fruit, twigs, and trunk scrapings were sampled monthly between August 1994 and January 1996. Open flowers were sampled in March from five of the sites. Two species of eupalopsellid mites (Exothorhis caudata Summers and Saniosulus harteni (van-Dis and Ueckermann)) were identified from 252 specimens collected within citrus tree canopies within the seven citrus orchards of which 249 were E. caudata. Only two E. caudata were collected from ground cover plants within five of the seven orchards. Eight species of Stigmaeidae were identified from 5,637 specimens: Agistemus floridanus Gonzalez, A. terminalis Gonzalez, Eustigmaeus arcuata (Chandhri), E. sp. near arcuata, E. segnis (Koch), Mediostigmaeus citri (Rakha and McCoy), Stigmaeus seminudus Wood, and Zetzellia languida Gonzalez were collected from within citrus tree canopies from seven orchard sites. Agistemus floridanus was the only species in either family that was abundant with 5,483 collected from within citrus tree canopies compared with only 39 from vine or ground cover plants. A total of 431 samples from one or more of 82 vines and ground cover plants were sampled monthly between September 1994 and January 1996 in five of these orchards and one or more eupalopsellids or stigmaeids were collected from 19 of these plants. Richardia brasiliensis (Meg.) Gomez had nine A. floridanus from 5 of 25 samples collected from this plant. Solanum sp. had five A. floridanus from three samples taken. Both eupalopsellid and stigmaeid species numbers represented <1 % of the total numbers of phytoseiid species taken from the same plants. The two remaining orchards were on full herbicide programs and ground cover plants were absent. Agistemus floridanus was more abundant in the citrus orchards
Khederi, Saeid Javadi; de Lillo, Enrico; Khanjani, Mohammad; Gholami, Mansur
The interaction of grape erineum mite (GEM), Colomerus vitis Pagenstecher (Acari: Eriophyidae), with grape was investigated in the laboratory. We studied some plant morphological biochemical features potentially related to vine resistance/tolerance of eight native grapevine cultivars, extensively cultivated in western Iran, and two non-native cultivars. Free-choice experiments indicated that the cultivars Shahani, Flame seedless and Yaghuti were colonized by lower levels of GEM, whereas Muscat Gordo, Gazne and White Thompson seedless hosted denser populations. These differences between cultivars may be due to differential attractiveness to GEM, possibly associated with plant biochemical and morphological traits. In no-choice assays with six grapevine cultivars, mite population development and some cultivar features were assessed. Mite populations grew fastest on Gazne and Muscat Gordo, and slowest on Yaghuti and Shahani. The degree of mite infestation was associated with reduction of leaf area, increase of leaf weight, shortening of shoots and more numerous erinea: these features were larger on the most infested Gazne, whereas morphological features of Shahani and Yaghuti were scarcely affected by GEM infestation. Also trichome type and density of the assayed cultivars appeared to be related to mite density: the most infested cultivars (Gazne and Muscat Gordo) displayed higher ranks of blade and vein hairs and lower ranks of blade and vein bristles and domatia. No correlation was found between mite density and leaf thickness of mature leaves. The amount of leaf waxes was highest in Shahani and Yaghuti, which displayed the lowest mite density, the fewest erinea and the largest leaves. Carbohydrate amount of uninfested leaves was lowest on the least infested Shahani and highest on the most infested Gazne; phenols increased in leaves of Shahani and decreased in those of Gazne after mite infestation. Finally, cultivars also appeared to influence some morphological
Shirotsuka, Kanako; Yano, Shuichi
Intraguild predation (IGP) is defined as the killing and eating of prey species by a predator that also can utilize the resources of the prey. It is mainly reported among carnivores that share common herbivorous prey. However, a large chewing herbivore could prey upon sedentary and/or micro herbivores in addition to utilizing a host plant. To investigate such coincidental IGP, we observed the behavioral responses of the polyphagous mite Tetranychus kanzawai Kishida (Acari: Tetranychidae) when its host plant Cayratia japonica (Thunb.) Gagnep. (Vitaceae) was attacked by hornworms, Theretra japonica Boisduval (Sphingidae) and T. oldenlandiae Fabricius (Sphingidae). We also examined an interaction between the oligophagous mite Panonychus citri McGregor (Acari: Tetranychidae) and caterpillars of the swallowtail Papilio xuthus L. (Papilionidae) that share citrus plants as their main food source. Although all T. kanzawai and some active stage P. citri tried to escape from the coincidental IGP, some were consumed together with eggs, quiescent mites, and host plant leaves, suggesting that coincidental IGP occurs on spider mites in the wild. Moreover, neither hornworms nor swallowtail caterpillars distinguished between spider mite-infested and uninfested leaves, suggesting that the mite-infested leaves do not discourage caterpillar feeding. The reasons that the mites have no effective defense against coincidental IGP other than escaping are discussed.
Hiraoka, H; Mori, N; Nishida, R; Kuwahara, Y
A mixture of two monoterpenes was obtained as the opisthonotal gland secretion from unidentified Histiogaster sp. A096 (Acari: Acaridae), and their structures were elucidated to be (4E)-dehydrocitrals [(2E,4E)- and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienals] by GC/MS, GC/FT-IR, UV and 1H-NMR spectra. Both isomers of (4E)-dehydrocitral prepared by syntheses in 4 steps from 3-methyl-2-butenal with 34.2% yields (based on the ylide) were separated by column chromatography into the (2E,4E)- and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienal. Mass spectra together with GC retention times of the purified natural (4E)-dehydrocitrals were identical with those of synthetic (2E,4E)-3,7-dimethyl-2,4,6-octatrienal and (2Z,4E)-3,7-dimethyl-2,4,6-octatrienal. The geometry at the 2-C position of both synthetic (4E)-dehydrocitrals was confirmed by NOESY analyses. This is the first identification of (4E)-dehydrocitrals from the animal kingdom.
Zhao, Ya-E; Wu, Li-Ping; Hu, Li; Xu, Yang; Wang, Zheng-Hang; Liu, Wen-Yan
Due to the difficulty of DNA extraction for Demodex, few studies dealt with the identification and the phyletic evolution of Demodex at molecular level. In this study, we amplified, sequenced, and analyzed a complete (Demodex folliculorum) and an almost complete (D12 missing) (Demodex brevis) ribosomal DNA (rDNA) sequence and also analyzed the primary sequences of divergent domains in small-subunit ribosomal RNA (rRNA) of 51 species and in large-subunit rRNA of 43 species from four superfamilies in Acari (Cheyletoidea, Tetranychoidea, Analgoidea, and Ixodoidea). The results revealed that 18S rDNA sequence was relatively conserved in rDNA-coding regions and was not evolving as rapidly as 28S rDNA sequence. The evolutionary rates of transcribed spacer regions were much higher than those of the coding regions. The maximum parsimony trees of 18S and 28S rDNA appeared to be almost identical, consistent with their morphological classification. Based on the fact that the resolution capability of sequence length and the divergence of the 13 segments (D1-D6, D7a, D7b, and D8-D12) of 28S rDNA were stronger than that of the nine variable regions (V1-V9) of 18S rDNA, we were able to identify Demodex (Cheyletoidea) by the indels occurring in D2, D6, and D8.
Hoy, Marjorie A.
Pesticide-resistant populations of the predatory mite Metaseiulus (= Typhlodromus or Galendromus) occidentalis (Arthropoda: Chelicerata: Acari: Phytoseiidae) have been used in the biological control of pest mites such as phytophagous Tetranychus urticae. However, the pesticide resistance mechanisms in M. occidentalis remain largely unknown. In other arthropods, members of the glutathione-S-transferase (GST), cytochrome P450 (CYP) and carboxyl/cholinesterase (CCE) gene superfamilies are involved in the diverse biological pathways such as the metabolism of xenobiotics (e.g. pesticides) in addition to hormonal and chemosensory processes. In the current study, we report the identification and initial characterization of 123 genes in the GST, CYP and CCE superfamilies in the recently sequenced M. occidentalis genome. The gene count represents a reduction of 35% compared to T. urticae. The distribution of genes in the GST and CCE superfamilies in M. occidentalis differs significantly from those of insects and resembles that of T. urticae. Specifically, we report the presence of the Mu class GSTs, and the J’ and J” clade CCEs that, within the Arthropoda, appear unique to Acari. Interestingly, the majority of CCEs in the J’ and J” clades contain a catalytic triad, suggesting that they are catalytically active. They likely represent two Acari-specific CCE clades that may participate in detoxification of xenobiotics. The current study of genes in these superfamilies provides preliminary insights into the potential molecular components that may be involved in pesticide metabolism as well as hormonal/chemosensory processes in the agriculturally important M. occidentalis. PMID:27467523
Infection and co-infection rates of Anaplasma phagocytophilum variants, Babesia spp., Borrelia burgdorferi, and the rickettsial endosymbiont in Ixodes scapularis (Acari: Ixodidae) from sites in Indiana, Maine, Pennsylvania, and Wisconsin.
Steiner, Fresia E; Pinger, Robert R; Vann, Carolyn N; Grindle, Nate; Civitello, David; Clay, Keith; Fuqua, Clay
In total, 394 questing adult blacklegged ticks, Ixodes scapularis Say (Acari: Ixodidae), collected at four sites were analyzed by polymerase chain reaction (PCR) for five microbial species: Anaplasma phagocytophilum, Babesia microti, Babesia odocoilei, Borrelia burgdorferi, and the rickettsial I. scapularis endosymbiont. Identities of genetic variants of A. phagocytophilum were determined by sequencing a portion of the 16S DNA. In 55% of infected ticks (193/351), a single agent was detected. In 45% (158/351), two or more agents were detected; 37% harbored two agents and 8% harbored three agents. One male tick, collected from Ft. McCoy, WI, harbored all four microbial genera The highest rates of co-infection were by the Ixodes endosymbiont and B. burgdorferi (95/351). Two species of Babesia co-occurred within a single tick population in Wells National Estuarine Research Reserve, Wells, ME, whereas only B. odocoilei was found in other tick populations. Only A. phagocytophilum human anaplasmosis variant was detected in questing ticks from Tippecanoe River State Park, IN; from Wells; and Ft. McCoy, whereas a single infected tick from Presque Isle, PA, was infected by AP-Variant 1. Partially engorged ticks from deer in Tippecanoe River State Park were all infected with AP-Variant 1. Frequency of infections with each agent varied among populations. Rates and types of co-infections were not significantly different from random except for the Ixodes endosymbiont and B. burgdorferi in male ticks, which co-occurred less frequently than expected. Thus, I. scapularis hosts an array of pathogenic and symbiotic agents and potential evidence of interactions among microbial species was observed.
Barbosa, Carolina da Silva; Borges, Lígia Miranda Ferreira; Louly, Carla Cristina Braz; Rocha, Thiago Lopes; de Sabóia-Morais, Simone Maria Teixeira; Miguita, Carlos Henrique; Garcez, Walmir Silva; Garcez, Fernanda Rodriguez
We evaluated the effects of 3β-O-tigloylmelianol from Guarea kunthiana A. Juss (Meliaceae) on oogenesis, as a larvicide and on ecdysis of the larvae and the nymphs of the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae). On the oogenesis' test, 48 engorged females were divided into three groups, evaluated at 24, 48 and 72 h post-treatment. Half of the females were treated with 0.01% 3β-O-tigloylmelianol diluted in distilled water and 5% dimethyl sulfoxide (DMSO), while the other half (controls) were exposed to distilled water and 5% DMSO. After treatment, the ovaries were weighed in order to measure the gonadosomatic index (GSI) and were also subjected to standard histological technical tests. On the larvicide and ecdysis' tests, 3β-O-tigloylmelianol was tested at concentrations of 0.01, 0.005, 0.0025 and 0.00125%. Compared with the controls, there was a reduction of GSI of approximately 50% on the treated group, which started at 48 h post treatment. Overall, the protolimonoid 3β-O-tigloylmelianol has caused a significant reduction in the number of oocytes. It has also caused alteration of the cytoplasmic and germinal vesicle diameters. Morphological changes, such as vacuolization, chorion irregularity which has modified the oocytes' morphology as well as alterations on the yolk's granules were also observed. The compound was not larvicide, however, interfered in the ecdysis of the larvae and the nymphs. This study shows that the protolimonoid 3β-O-tigloylmelianol from G. kunthiana acts on oogenesis and ecdysis of R. (B.) microplus, but not as larvicide, indicating that it acts on the endocrine system of the tick.
Chemical composition and acaricidal activity of the essential oil of Baccharis dracunculifolia De Candole (1836) and its constituents nerolidol and limonene on larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae).
de Assis Lage, Tiago Coelho; Montanari, Ricardo Marques; Fernandes, Sergio Antonio; de Oliveira Monteiro, Caio Márcio; de Oliveira Souza Senra, Tatiane; Zeringota, Viviane; da Silva Matos, Renata; Daemon, Erik
Baccharis dracunculifolia DC (common name "alecrim-do-campo" in Brazil) is a plant with widespread distribution in South America that is the botanical origin of green propolis. The aim of this study was to evaluate the chemical composition and acaricidal activity of the essential oil of B. dracunculifolia and its constituents nerolidol and limonene on unengorged larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae). The essential oil yield was 0.8% of dry mass and the major constituents were nerolidol (22.3%), germacrene D (7.2%), limonene (6.9%), β-pinene (6.7) and bicyclogermacrene (6.5%). The acaricidal activity of the essential oil and the pure compounds nerolidol and (R)-(+)-limonene were assessed in the laboratory through the modified larval packet test (LPT) and the female immersion test (FIT). In the LPT, the essential oil and nerolidol were both active, causing more than 90% mortality at concentrations from 15.0 and 10.0 mg mL(-1), respectively, whereas (R)-(+)-limonene was not active. In the FIT, the oil and nerolidol caused reduction in the quantity and quality of eggs produced, with control percentages of 96.3% and 90.3% at concentrations of 60.0 and 50.0 mg mL(-1), respectively. It can be concluded that the essential oil obtained from the aerial parts of B. dracunculifolia and its major component nerolidol have high activity on R. microplus larvae and engorged females. Copyright © 2014 Elsevier Inc. All rights reserved.
The Tenuipalpidae from the Casuarinaceae are reviewed. Twelve new species are described, from one new genus and six established genera: Chaudhripalpus costacola Beard & Seeman sp. nov., Crossipalpus gersoni Beard & Seeman sp. nov., Crossipalpus raveni Beard & Seeman sp. nov., Magdalenapalpus capera...
Kawakami, Yuko; Numata, Hideharu; Ito, Katsura; Goto, Shin G
In this study, we investigated the diapause incidence in 3 geographic strains of the two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae). Under diapause-inducing conditions of 12:12 light:dark at 15 degrees C, the diapause incidence was nearly 100% in a strain from northern Japan (Sapporo), whereas it was nearly 0% in 2 strains from southern Japan (Itoman and Takanabe). Reciprocal crosses clearly showed that the nondiapause phenotype is inherited in a completely dominant manner, and no maternal effect was detected. Backcrosses to the Itoman and Takanabe strains suggested that dominant nondiapause alleles control the nondiapause phenotype. To clarify the genetic basis of nondiapause in the northern population, we also established a nondiapausing variant ("selected nondiapause" abbreviated as snd) from the Sapporo strain. Crossing experiments revealed that a single recessive allele is responsible for the nondiapause phenotype. Thus, both dominant and recessive inheritance patterns of diapause were detected in the T. urticae populations studied here.
Mendonça, Renata S; Navia, Denise; Diniz, Ivone R; Flechtmann, Carlos HW
In order to contribute to taxonomic information on Tetranychid mites (Acari: Tetranychidae) in South America, surveys were conducted in Brazil (15 States and the Federal District) and Uruguay (one Department); 550 samples of 120 plant species were collected. Tetranychid mite infestations were confirmed in 204 samples, and 22 species belonging to seven genera of the Bryobiinae and Tetranychinae subfamilies were identified on 58 different host plants. Thirty-six new plant hosts were found in Brazil, South America, and worldwide for the following species: Eutetranychus banksi (McGregor); Mononychellus tanajoa (Bondar); Oligonychus anonae Paschoal; O. mangiferus (Rahman and Sapra); Tetranychus bastosi Tuttle, Baker and Sales; T. desertorum Banks, 1900, T. evansi Baker and Pritchard; T. ludeni Zacher; T. mexicanus (McGregor); T. neocaledonicus André; and T. urticae Koch. Four new localities in Brazil were reported for Eotetranychus tremae De Leon; O. anonae; Panonychus ulmi (Koch); and T. gloveri Baker and Pritchard. PMID:22224405
Chiasson, H; Bostanian, N J; Vincent, C
The emulsifiable concentrate UDA-245 [25% EC (vol:vol)], based on an essential oil extract from Chenopodium ambrosioides variety ambrosioides, a North American herbaceous plant, was compared with commercially available pesticides for their effectiveness to control the adult stage and egg hatch of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) and the European red mite, Panonychus ulmi (Koch) (Acari: Tetranychidae). After a laboratory bioassay with adult twospotted spider mites, a 0.5% concentration of UDA-245 was more effective than 0.7% (AI) of neem oil (Neem Rose Defense). After a similar bioassay with the European red mite, a 0.5% concentration UDA-245 was as effective as 0.006% (AI) of abamectin (Avid). UDA-245 at 0.5% significantly reduced egg hatch of the twospotted spider mite, 5 and 9 d after treatment and of the European red mite 6 d after treatment. Egg hatch was significantly lower using 0.006% (AI) of abamectin, 0.7% of neem oil, and 1.0% insecticidal soap than UDA-245. Residual tests indicated that UDA-245 may be persistent in the environment only for a few hours. Only 23% mortality was noted when mites were introduced on bean leaves 1 h after treatment with a 2% concentration of UDA-245. At the recommended dose of 0.5%, UDA-245 was not considered phytotoxic for most plants tested, i.e., lettuce, roses, and tomatoes. Results suggest that a greenhouse integrated pest management program using UDA-245 could effectively and selectively control mite infestations by treating "hot spots" with negligible effect on biological control agents when treating before introduction or when natural enemies are absent.
Franco, Aline Aparecida; Zanardi, Odimar Zanuzo; Jacob, Cynthia Renata de Oliveira; de Oliveira, Monique Bárbara Rosa; Yamamoto, Pedro Takao
Euseius concordis (Chant) is an important predatory mite found in citrus orchards. The toxicity of 19 pesticides used in citrus orchards on biological and population parameters of this mite was assessed. Our results indicated that formetanate hydrochloride, dimethoate and phosmet were highly harmful (100% mortality) to E. concordis. Carbosulfan, diflubenzuron, fenpropathrin, gamma-cyhalothrin, imidacloprid, lambda-cyhalothrin, lambda-cyhalothrin + thiamethoxam, mineral and vegetable oils, spinosad and thiamethoxam reduced the female's survival and/or fecundity, and were moderately harmful to E. concordis. Besides the acute toxicity, carbosulfan and formetanate hydrochloride were highly persistent [>30 days after spraying (DAS)]; dimethoate was moderately persistent (16-30 DAS); spinosad, gamma-cyhalothrin, lambda-cyhalothrin and lambda-cyhalothrin + thiamethoxam were slightly persistent (5-15 DAS); and the other pesticides were considered to be short-lived (<5 DAS). All compounds except lambda-cyhalothrin and thiamethoxam increased the pre-oviposition period in the female offspring. Carbosulfan, deltamethrin, diflubenzuron, etofenprox, fenpropathrin, gamma-cyhalothrin, mineral and vegetable oils, pyriproxyfen and tebufenozide reduced offspring fecundity, whereas thiamethoxam increased the fecundity. Mineral and vegetable oils reduced female longevity of the predator mite. Regarding population effects, imidacloprid, lambda-cyhalothrin, lambda-cyhalothrin + thiamethoxam and thiamethoxam led to an increase in net reproductive rate (R o ), intrinsic rate of increase (r), and finite rate of increase (λ) of E. concordis. Diflubenzuron, etofenprox, and mineral and vegetable oils reduced R o , r and λ. All pesticides except beta-cypermethrin, fenpropathrin and imidacloprid reduced the mean generation time (T) of the predator. Therefore, semi-field and field studies are needed to assess the compatibility of these compounds with E. concordis before adoption in IPM programs.
Zanuzo Zanardi, Odimar; Pavan Bordini, Gabriela; Aparecida Franco, Aline; Jacob, Cynthia Renata Oliveira; Takao Yamamoto, Pedro
The predator mite Iphiseiodes zuluagai Denmark & Muma is an important biological-control agent of mite pests, and it is one of the most common species found in citrus orchards. This study assessed, under laboratory conditions, the toxicity and duration of the harmful effects of five insecticides, the three pyrethroids deltamethrin, esfenvalerate and lambda-cyhalothrin, and the two neonicotinoids imidacloprid and thiamethoxam on I. zuluagai. Furthermore, we estimated the life-table parameters of the predator. Our results showed that deltamethrin and lambda-cyhalothrin caused higher mortality of larvae and adults than imidacloprid and thiamethoxam. In contrast, esfenvalerate provided larval mortality similar to imidacloprid and thiamethoxam, but it did not cause significant adult mortality of the predator. Mites that developed on pyrethroid residues showed lower survival of the immature stages, fecundity, and longevity compared to neonicotinoid residues and the control treatment. The estimated life-table parameters indicated that deltamethrin, lambda-cyhalothrin and esfenvalerate caused greater reduction in R o and r of I. zuluagai compared with imidacloprid and thiamethoxam, which were similar to the control treatment. Besides the impacts on biological and population parameters, the duration of the harmful activity of pyrethroid insecticides was longer than the neonicotinoids. Therefore, the use of pyrethroid insecticides to control pest insects may involve serious implications for integrated pest-management programs that aim to exploit the biological control by I. zuluagai in citrus orchards.
Lima, Debora B; Melo, José Wagner S; Guedes, Nelsa Maria P; Gontijo, Lessando M; Guedes, Raul Narciso C; Gondim, Manoel Guedes C
Synthetic pesticide use has been the dominant form of pest control since the 1940s. However, biopesticides are emerging as sustainable pest control alternatives, with prevailing use in organic agricultural production systems. Foremost among botanical biopesticides is the limonoid azadirachtin, whose perceived environmental safety has come under debate and scrutiny in recent years. Coconut production, particularly organic coconut production, is one of the agricultural systems in which azadirachtin is used as a primary method of pest control for the management of the invasive coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae). The management of this mite species also greatly benefits from predation by Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae). Here, we assessed the potential behavioral impacts of azadirachtin on the coconut mite predator, N. baraki. We explored the effects of this biopesticide on overall predator activity, female searching time, and mating behavior and fecundity. Azadirachtin impairs the overall activity of the predator, reducing it to nearly half; however, female searching was not affected. In contrast, mating behavior was compromised by azadirachtin exposure particularly when male predators were exposed to the biopesticide. Consequently, predator fecundity was also compromised by azadirachtin, furthering doubts about its environmental safety and selectivity towards biological control agents.
Vásquez, Carlos; de Moraes, Gilberto J
The red palm mite (RPM), Raoiella indica Hirst (Acari: Tenuipalpidae), is an invasive pest in the New World, where it is currently considered a serious threat to coconut and banana crops. It was first reported from northern Venezuela in 2007. To determine its current distribution in this country, surveys were carried out from October 2008 to April 2010 on coconut (Cocos nucifera L.), banana (Musa spp.), ornamental plants and weeds in northern Venezuela. Higher population levels of RPM were registered on commercial coconut farms in Falcón and Sucre states but also on other plant species naturally growing along the coastal line in Anzoategui, Aragua, Carabobo, Monagas and Nueva Esparta states. Out of 34 botanical species evaluated, all RPM stages were observed only on eight arecaceous, one musaceous and one streliziaceous species, indicating that the pest developed and reproduced only on these plants. Mite specimens found on weeds were considered spurious events, as immature stages of the pest were never found on these. Amblyseius largoensis (Muma) (Acari: Phytoseiidae) was the most frequent predatory mite associated with RPM in all sampling sites. The results indicate that RPM has spread to extensive areas of northern Venezuela since its initial detection in Güiria, Sucre state. Considering the report of this pest mite in northern Brazil in the late 2009, additional samplings in southern Venezuela should be carried out, to evaluate the possible presence of RPM also in that region.
Lima, Debora B.; Melo, José Wagner S.; Guedes, Nelsa Maria P.; Gontijo, Lessando M.; Guedes, Raul Narciso C.; Gondim, Manoel Guedes C.
Synthetic pesticide use has been the dominant form of pest control since the 1940s. However, biopesticides are emerging as sustainable pest control alternatives, with prevailing use in organic agricultural production systems. Foremost among botanical biopesticides is the limonoid azadirachtin, whose perceived environmental safety has come under debate and scrutiny in recent years. Coconut production, particularly organic coconut production, is one of the agricultural systems in which azadirachtin is used as a primary method of pest control for the management of the invasive coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae). The management of this mite species also greatly benefits from predation by Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae). Here, we assessed the potential behavioral impacts of azadirachtin on the coconut mite predator, N. baraki. We explored the effects of this biopesticide on overall predator activity, female searching time, and mating behavior and fecundity. Azadirachtin impairs the overall activity of the predator, reducing it to nearly half; however, female searching was not affected. In contrast, mating behavior was compromised by azadirachtin exposure particularly when male predators were exposed to the biopesticide. Consequently, predator fecundity was also compromised by azadirachtin, furthering doubts about its environmental safety and selectivity towards biological control agents. PMID:25679393
Cuthbertson, Andrew G. S.; Qiu, Bao-Li; Murchie, Archie K.
The increasing concern over the continued use of pesticides is pressurising apple growers to look for alternatives to chemical pest control. The re-discovery, and subsequent conservation, of the beneficial predatory mite, Anystis baccarum (Linnaeus) (Acari: Anystidae), in Bramley apple orchards in Northern Ireland offers a potential alternative control component for incorporation into integrated pest management strategies. Anystis baccarum readily feeds upon economically important invertebrate pest species including European fruit tree red spider mite, Panonychus ulmi (Koch) (Acari: Tetranychidae) and show a level of compatibility with chemical pesticides. Recent mis-identification by apple growers of this beneficial mite species had resulted in unnecessary pesticide applications being applied within Northern Irish apple orchards. However, dissemination of information to the apple growers and promotion of the benefits this mite offers in apple orchards has helped to conserve its populations. Apple growers, across the United Kingdom, must be encouraged to be aware of A. baccarum, and indeed all predatory fauna, within their orchards and seek to conserve populations. In doing so, it will ensure that the British apple market remains an environmentally sustainable production system. PMID:26462829
Coombs, Megan R; Bale, Jeffrey S
The lower and upper thermal activity thresholds of adult and larval Balaustium hernandezi von Heyden (Acari: Erythraeidae) are compared with those of its prey Tetranychus urticae Koch (Acari: Tetranychidae). Adult female B. hernandezi retain ambulatory function (CTmin) and movement of appendages (chill coma) at significantly lower temperatures (5.9 and −2.1 °C, respectively) than those of larval B. hernandezi (8.1 and −1.7 °C) and T. urticae (10.6 and 10.3 °C). There is no significant difference between the temperature at which adult and larval B. hernandezi and T. urticae cease walking as the temperature is raised (CTmax) (46.7, 46.3 and 47.3 °C, respectively). However, both life stages of B. hernandezi cease movement (heat coma) below the upper locomotory limits of T. urticae (46.8, 46.7 and 48.7 °C, respectively). Adult B. hernandezi have significantly faster walking speeds than larvae and T. urticae across a range of temperatures. The lower thermal activity threshold data indicate that B. hernandezi would make an effective biological control agent in temperate climates; however, the extent of the low temperature tolerances of the species suggests the potential to establish in a northern European climate. PMID:26279601
Cuthbertson, Andrew G S; Qiu, Bao-Li; Murchie, Archie K
The increasing concern over the continued use of pesticides is pressurising apple growers to look for alternatives to chemical pest control. The re-discovery, and subsequent conservation, of the beneficial predatory mite, Anystis baccarum (Linnaeus) (Acari: Anystidae), in Bramley apple orchards in Northern Ireland offers a potential alternative control component for incorporation into integrated pest management strategies. Anystis baccarum readily feeds upon economically important invertebrate pest species including European fruit tree red spider mite, Panonychus ulmi (Koch) (Acari: Tetranychidae) and show a level of compatibility with chemical pesticides. Recent mis-identification by apple growers of this beneficial mite species had resulted in unnecessary pesticide applications being applied within Northern Irish apple orchards. However, dissemination of information to the apple growers and promotion of the benefits this mite offers in apple orchards has helped to conserve its populations. Apple growers, across the United Kingdom, must be encouraged to be aware of A. baccarum, and indeed all predatory fauna, within their orchards and seek to conserve populations. In doing so, it will ensure that the British apple market remains an environmentally sustainable production system.
de Saraiva, Althiéris Souza; Sarmento, Renato Almeida; Pedro-Neto, Marçal; Teodoro, Adenir Vieira; Erasmo, Eduardo Andrea Lemus; Belchior, Diana Cléssia Vieira; de Azevedo, Emiliano Brandão
Weed management in physic nut plantations has generally been performed by spraying the herbicide glyphosate. However, the effects of glyphosate on non-target organisms present in the crop system are unknown. Here, we evaluated the toxicity of glyphosate (Roundup Transorb(®)) against the pest species Polyphagotarsonemus latus (Acari: Tarsonemidae) and Tetranychus bastosi (Acari: Tetranychidae) which can be exposed by drift. These mites are considered pests of the physic nut; however, they can also feed and reside on weeds associated with the crop, serving as food sources for predatory mites. When subjected to residue (by ingestion of sap of treated plants), and direct contact to glyphosate, P. latus reproduction was affected but T. bastosi was affected only by the residual effect. Although the herbicide caused a reduction in the number of eggs laid by the females of both pest mites, it is suggested that sublethal effects of glyphosate stimulates oviposition of P. latus and T. bastosi: both species displayed higher reproductive rates when exposed to 0.36 kg ha(-1) of the herbicide. We conclude that glyphosate negatively affects the arthropod herbivores studied and we discuss possible implications on their biological control in Jatropha curcas plantations.
Pérez-Sayas, Consuelo; Pina, Tatiana; Gómez-Martínez, María A; Camañes, Gemma; Ibáñez-Gual, María V; Jaques, Josep A; Hurtado, Mónica A
Gut content analysis using molecular techniques can help elucidate predator-prey relationships in situations in which other methodologies are not feasible, such as in the case of trophic interactions between minute species such as mites. We designed species-specific primers for a mite community occurring in Spanish citrus orchards comprising two herbivores, the Tetranychidae Tetranychus urticae and Panonychus citri, and six predatory mites belonging to the Phytoseiidae family; these predatory mites are considered to be these herbivores' main biological control agents. These primers were successfully multiplexed in a single PCR to test the range of predators feeding on each of the two prey species. We estimated prey DNA detectability success over time (DS50), which depended on the predator-prey combination and ranged from 0.2 to 18 h. These values were further used to weight prey detection in field samples to disentangle the predatory role played by the most abundant predators (i.e. Euseius stipulatus and Phytoseiulus persimilis). The corrected predation value for E. stipulatus was significantly higher than for P. persimilis. However, because this 1.5-fold difference was less than that observed regarding their sevenfold difference in abundance, we conclude that P. persimilis is the most effective predator in the system; it preyed on tetranychids almost five times more frequently than E. stipulatus did. The present results demonstrate that molecular tools are appropriate to unravel predator-prey interactions in tiny species such as mites, which include important agricultural pests and their predators.
Cruz, Wilton P; Sarmento, Renato A; Teodoro, Adenir V; Neto, Marçal P; Ignacio, Maíra
Seasonal changes in climate and plant diversity are known to affect the population dynamics of both pests and natural enemies within agroecosystems. In Brazil, spontaneous plants are usually tolerated in small-scale physic nut plantations over the year, which in turn may mediate interactions between pests and natural enemies within this agroecosystem. Here, we aimed to access the influence of seasonal variation of abiotic (temperature, relative humidity and rainfall) and biotic (diversity of spontaneous plants, overall richness and density of mites) factors on the communities of phytophagous and predatory mites found in a physic nut plantation and its associated spontaneous plants. Mite sampling was monthly conducted in dicotyledonous and monocotyledonous leaves of spontaneous plants as well as in physic nut shrubs over an entire year. In the dry season there was a higher abundance of phytophagous mites (Tenuipalpidae, Tarsonemidae and Tetranychidae) on spontaneous plants than on physic nut shrubs, while predatory mites (Phytoseiidae) showed the opposite pattern. The overall density of mites on spontaneous plants increased with relative humidity and diversity of spontaneous plants. Rainfall was the variable that most influenced the density of mites inhabiting physic nut shrubs. Agroecosystems comprising spontaneous plants associated with crops harbour a rich mite community including species of different trophic levels which potentially benefit natural pest control due to increased diversity and abundance of natural enemies.
Navia, Denise; Marsaro, Alberto L
The citrus Hindu mite, Schizotetranychus hindustanicus (Hirst), is reported for the first time in Brazil and for the second time in South America. Mite specimens were collected from citrus in the municipality of Boa Vista, State of Roraima, northern Brazil. Symptoms associated with S.hindustanicus infestations on citrus are described. The importance of avoiding dissemination of this mite to the main citrus production areas in Brazil is discussed.
Tenuipalpus Donnadieu is the most speciose genus of the family Tenuipalpidae, with over 300 described species. The descriptions of many of these species are incomplete, and lack important information necessary for accurate species identification. The objective of this study was to re-describe specie...
Tulin Askit; Ibrahim Cakmak; John Moser
The Aegean Region of Turkey is one of the largest dried fig producers in the world. A Turkish cultivar sarilop (Ficus carica cv. Calimyrna L.) possesses good qualities for drying process, and has been grown extensively for many years in Turkey. Hypoborus ficus is the most common xylophagous insect attacking fig trees in Aydin (AksÂ¸it et al. 2003). This pest attacks...
Abstract The present paper is based on original and literature data. In Croatia the first studies on the occurrence of ixodid species were made about 80 years ago. The number of tick species recorded in Croatia considerably increased during the 1950s, 60s, 70s and 80s of the past century. A total of 21 species of hard tick belonging to 5 genera have been recorded in Croatia. Ixodes is the best represented genus, with seven species recorded. Haemaphysalis is represented by six species, followed by Rhipicephalus with four species. Dermacentor and Hyalomma are represented by two species each. The ticks were collected on 47 different host species. Eleven tick species were collected on Bos taurus and Ovis aries, followed by Capra hircus and Equus caballus with 8 species and Canis lupus familiaris with 6 species. On the remaining 42 host species one, two or three tick species were collected. The most widespread tick is Ixodes ricinus which was found on 25 different host species. PMID:23372407
Ermilov, Sergey G; Friedrich, Stefan
Six species of oribatid mites of the genus Pergalumna (Oribatida, Galumnidae) are collected from the German Expedition to Amazonian Peru in 2013; of these, three are new for science, described from upper soil and leaf litter in the primary evergreen lowland rainforest. Pergalumna (Pergalumna) parapassimpunctata sp. nov. is morphologically most similar to P. (P.) passimpunctata Balogh & Mahunka, 1969, but differs from the latter by the presence of foveolate body surface, two pairs of porose areas Aa and minute interlamellar setae, and the absence of porose areas A3. Pergalumna (Pergalumna) krisperi sp. nov. is morphologically most similar to P. (P.) cardosensis Pérez-Íñigo & Baggio, 1986, but differs from the latter by the smaller body size, rostral and lamellar setae of medium size and the presence of four pairs of notogastral porose areas. Pergalumna (Pergalumna) lenticulata sp. nov. is morphologically most similar to P. (P.) decorata Balogh & Mahunka, 1977, but differs from the latter by the larger body size and the presence of lenticulus and bidentate rostrum. The species Pergalumna (Pergalumna) bryani Jacot, 1934 is recorded for the first time in Peru.
Beard, Jennifer J; Seeman, Owen D; Bauchan, Gary R
The Tenuipalpidae associated with the Casuarinaceae are reviewed, including one new genus, Palpipalpus gen. nov., twelve new species, and seven redescriptions. Two new generic records for Australia are established, Pentamerismus and Philippipalpus. The new species are: Chaudhripalpus costacola Beard and Seeman sp. nov., Crossipalpus gersoni Beard and Seeman sp. nov., Crossipalpus raveni Beard and Seeman sp. nov., Magdalenapalpus caperatus Beard and Seeman sp. nov., Magdalenapalpus forsteri Seeman and Beard sp. nov., Pentamerismus sititoris Beard and Seeman sp. nov., Pentamerismus hicklingorum Seeman and Beard sp. nov., Pentamerismus wardo Seeman and Beard sp. nov., Palpipalpus hesperius Beard and Seeman sp. nov. gen. nov., Philippipalpus flumaquercus Beard and Seeman sp. nov., Philippipalpus belah Beard and Seeman sp. nov., and Philippipalpus nigraquercus Seeman and Beard sp. nov. Meyeraepalpus delfinadae Smiley et al., is reinstated based on new material and an analysis of its phylogenetic relationships. Crossipalpus muellerianae Smiley et al., Crossipalpus verticillatae Smiley et al., and Tegopalpus conicus Womersley are redescribed and rediagnosed from the original type specimens and newly collected material; and Chaudhripalpus creelae (Smiley et al.), Magdalenapalpus strandtmanni (Smiley et al.) and Philippipalpus agohoi Corpuz-Raros are redescribed and rediagnosed from type material only. All flat mite species were host-specific. Up to three species of flat mite were collected from a single she-oak species. Leg setation and ontogeny are reviewed for the taxa studied. A key to Tenuipalpidae from Casuarinaceae is provided. A phylogeny of the subfamily Tegopalpinae found the following relationships: Meyeraepalpus (Australopalpus, Crossipalpus, Palpipalpus (Magdalenapalpus (Philippipalpus (Chaudhripalpus + Tegopalpus)))). Our preliminary analysis of the Tegopalpinae suggested the group is monophyletic and its sister group is Phytoptipalpus.
Pascual Izaola, A; Sánchez Milla, J J; Mateo Garmilla, J I; Antépara, I
In this work we collect the results of the variation of the variable "rechange of the wind with the exterior" in the three possibilities of a bedroom: --close window, semi close and totally open. And we unite the relation that we already know between the prevail of acariens (Dermatophagoides) and the relative humidity of the wind in a Bilbao city's house.
Nava, Santiago; Estrada-Peña, Agustín; Mangold, Atilio J; Guglielmone, Alberto A
The life cycle of Amblyomma neumanni was described studying the seasonal distribution of free-living stages and parasitic phases during two consecutive years. Development periods of engorged ticks under different photoperiod conditions were recorded. Larvae of A. neumanni have the peak of abundance in autumn. Nymphs reach the peak in winter. Females were collected on cattle from autumn to late spring. The seasonal distribution pattern of females showed a bimodal curve, with a peak in autumn and other during early and middle spring. The engorged females exposed at shortest photoperiod regimen (10 h light-14 h dark) under both laboratory and field conditions undergo morphogenetic diapause, expressed as a delay in the oviposition. It is concluded that females of A. neumanni that feed and copulate in autumn undergo morphogenetic diapause, and they will lay eggs in spring, simultaneously with the females that feed and copulate in this season. Climate niche analysis shows that adequate suitability for A. neumanni depends mainly from temperature (mean, absolute maximum and minimum, and mean temperature in wettest and driest quarters) as well as from rainfall in warmest and coldest quarters. Sequences of 16S rDNA gene belonging to different populations of A. neumanni, showed no intraspecific genetic differentiation.
Oliveira, Natália N F C; Galvão, Andreia S; Amaral, Ester A; Santos, Auderes W O; Sena-Filho, José G; Oliveira, Eugenio E; Teodoro, Adenir V
The coconut mite, Aceria guerreronis (Acari: Eriophyidae), is a major tropical pest of coconut. Here, we assessed the chemical profiles and the potential use of babassu, degummed soybean, and coconut oils to control A. guerreronis as well as their side-effects on the predatory mite Neoseiulus baraki (Acari: Phytoseiidae), a key natural enemy of the coconut mite. Babassu and coconut oils had similar fatty acids chemical profiles. All vegetable oils showed toxicity to A. guerreronis; degummed soybean oil exhibited the highest toxicity (LC50 = 0.15 µL/cm(2)). Although all oils were less toxic to N. baraki, their potential to attract/repel this predatory mite differed. Whereas N. baraki females were unresponsive to coconut oil at both concentrations (i.e., LC50 and LC99 estimated for A. guerreronis), irrespective of exposure period (i.e., 1 or 24 h), the babassu oil repelled the predator, independent of exposure period, when applied at its LC99 (1.48 µL/cm(2)). Intriguingly, this oil also exhibited attractiveness to N. baraki 24 h after exposure when applied at its LC50 (0.26 µL/cm(2)). A similar attractiveness pattern was recorded 24 h after N. baraki was exposed to degummed soybean oil at both concentrations tested (LC50 = 0.15 µL/cm(2); LC99 = 1.39 µL/cm(2)). However, N. baraki was repelled by degummed soybean oil at its LC50 after 1 h of exposure. Therefore, the present study demonstrated that all the vegetable oils used here had higher toxicity to the coconut mite and considerable selectivity to the predator N. baraki, indicating they are promising tools that can potentially be included in management programs to control A. guerreronis in commercial coconut plantations.
de Monteiro, Caio Márcio; Maturano, Ralph; Daemon, Erik; Catunda-Junior, Francisco Eduardo Aragão; Calmon, Fernanda; Senra, Tatiane de Souza; Faza, Aline; de Carvalho, Mário Geraldo
The aim of this study was to evaluate the acaricidal activity of eugenol, with different solubilizations and concentrations, on Rhipicephalus microplus and Dermacentor nitens larvae and to determine the lethal time. The study consisted of four experiments, and the mortality was assessed using the larval packet test with adaptations. The mortality observed in the first experiment was 100 % for all the groups treated with eugenol solubilized in different solvents. In the second, the hydroethanolic formulation of eugenol was used, and the mortality rates for R. microplus and D. nitens was 100 % starting from the concentration of 5.0 μl/ml. In the third experiment, the mortality was 100 % for larvae of both R. microplus and D. nitens after 1 h of contact. And in the fourth experiment, the mortality was above 90 % and statistically similar (p > 0.05) for the four methods the test evaluated.
Zhao, Yunlong; Li, Dunsong; Zhang, Min; Chen, Wei; Zhang, Guren
Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae) is one of the most widely used and important biological control agents for thrips and other small pests worldwide. In the present study, we cloned two cDNAs of vitellogenins (Vgs, NcVg1 and NcVg2) and analyzed the effect of food source on the expression of both Vgs and fecundity in female adults. NcVgs showed higher sequence similarity to Vgs from Parasitiformes. Both neighbor-joining and maximum likelihood methods for phylogenetic analysis of NcVgs yielded similar topologies and showed that the Parasitiformes except Haemaphysalis longicornis segregated into a single clade that was separated into two subclades including one of both Vgs from N. cucumeris. Both transcripts, NcVg1 and NcVg2 revealed similar trends during developmental periods and reached the maximum level at the pre-oviposition period. When fed with different food sources, both NcVg1 and NcVg2 of female adults demonstrated a significant difference (P < 0.05) during the pre-oviposition period. Meanwhile, a positive correlation between the expression of Vgs and fecundity was observed. Therefore, the nutrients provided by the food sources affected fecundity resulting in differential expression of Vgs. Vitellogenin expression can be used as a molecular marker of fecundity of N. cucumeris.
Medd, Nathan C; GreatRex, Richard M
Within integrated pest control programmes, the use of high mite inoculations to control hot spots of whitefly is desirable for many growers. In this experiment, two species of predatory mites established as commercial biological control agents, Typhlodromips montdorensis and Amblyseius swirskii (Acari: Phytoseiidae), were compared with another, more recently introduced species, Amblydromalus limonicus, for their ability to control dense populations of greenhouse whitefly (Trialeurodes vaporariorum) on cucumber plants (Cucumis sativus). Mite formulation type had a significant effect on the number of mites found on plants, but this did not correspond to increased whitefly control. Plots treated with A. limonicus or T. montdorensis, applied as loose product, had significantly reduced whitefly populations throughout the trial. Analysis showed that no species was observed more often on leaves with higher whitefly densities than on those with lower densities. No species was clearly identified as a suitable candidate for treatment of high-density whitefly colonies, but results suggest the highest level of predation in A. limonicus. Strategies for the effective use of these predatory mite species in control programmes are discussed. © 2014 Society of Chemical Industry.
Elliot, Sam L; De Moraes, Gilberto J; Mumford, John D
The mite-pathogenic fungus Neozygites floridana Fisher (Entomophthorales: Neozygitaceae) is considered to have potential for the biological control of the cassava green mite, Mononychellus tanajoa (Bondar). However, its activity is sporadic and laboratory data suggest a strong dependence on night-time saturation deficits for transmission. We report on an epizootic of this fungus in a mite population in northeastern Brazil. During the epizootic, host populations appeared to he limited by a combination of the pathogen and a predatory mite Neoseiulus idaeus (Acari: Phytoseiidae). When temperatures increased, the epizootic finished and the host population began to grow. Abiotic conditions could not explain the variation in host mortality following pickup of infective propagules in this epizootic. However, night-time saturation did help to explain the variation in transmission from infective cadavers to newly killed hosts. This supports laboratory observations that horizontal transmission between hosts is determined mainly by saturation deficits, while the process of infection is little affected by abiotic conditions. A further field observation was the near-absence of resting spores in dead mites (ca. 0.1% of cadavers), suggesting that the pathogen population was unsuccessful in producing inoculum to infect future M. tanajoa populations. The implications are that this pathogen will only be effective as a biological control agent in periods of high relative humidity, and establishment in new areas may be limited by resting spore formation.
Palevsky, Eric; Gerson, Uri; Zhang, Zhi-Qiang
Numerous natural enemies were adopted worldwide for the control of major pests, including exotic phytoseiid species (Acari: Mesostigmata: Phytoseiidae) that had been moved from continent to continent in protected and perennial agricultural systems. However, relatively fewer successes were recorded in perennial agricultural systems. In this manuscript we focus on the question: Can and will exotic phytoseiids provide better pest control than indigenous species in perennial agricultural systems? To answer this question, we review the efficacy of biological control efforts with phytoseiids in several case studies, where exotic and indigenous species were used against pests on indigenous host plants and some crops that were historically or recently introduced. Related factors affecting predator establishment, such as intraguild predation and pesticide effects are discussed, as well as the potential negative effects of exotic species releases on biological control and their impact on the indigenous natural fauna. On citrus, apple, grape and cassava exotic phytoseiids have enhanced biological control without negatively affecting indigenous species of natural enemies, except for the case of Euseius stipulatus (Athias-Henriot) on citrus that displaced Euseius hibisci (Chant) in a limited region of coastal California, USA, the latter considered to be an inferior biocontrol agent of Panonychus citri Koch. Phytoseiulus persimilis Athias-Henriot on gorse, an invasive weed, is perhaps the only recorded case of a negative effect of an established exotic phytoseiid on biological control.
Duarte, Mércia E; Navia, Denise; dos Santos, Lucas R; Rideiqui, Pedro J S; Silva, Edmilson S
In some Brazilian regions the Atlantic forest biome is currently restrict to fragments occurring amid monocultures, as sugarcane crops in the Northeast region. Important influence of forest remnants over mite fauna of permanent crops have been showed, however it has been poorly explored on annual crops. The first step for understanding ecological relationship in an agricultural systems is known its composition. The objective of this study was to investigate the plant-inhabiting mite fauna associated with sugarcane crop (Saccharum officinarum L.) (Poaceae) and caboatã (Cupania oblongifolia Mart.) (Sapindaceae) trees in the state of Alagoas, Brazil. Sugarcane stalks and sugarcane and caboatã apical, middle and basal leaves were sampled. A total of 2565 mites were collected from sugarcane and classified into seven families of Trombidiformes and Mesostigmata orders, with most individuals belonging to the Eriophyidae, Tetranychidae and Tarsonemidae families. Among predatory mites, the Phytoseiidae were the most common. A total of 1878 mites were found on C. oblongifolia and classified into 13 families of Trombidiformes and Mesostigmata orders. The most abundant phytophagous mite family on caboatã was also Eriophyidae. In contrast to sugarcane, Ascidae was the most common predatory mite family observed in caboatã. No phytophagous species were common to both sugarcane and C. oblongifolia. However two predatory mites were shared between host plants. Although mites associated with only one native species in the forest fragment were evaluated in this study, our preliminary results suggest Atlantic forest native vegetation can present an important role in the sugarcane agricultural system as a source of natural enemies.
Bensoussan, Nicolas; Santamaria, M. Estrella; Zhurov, Vladimir; Diaz, Isabel; Grbić, Miodrag; Grbić, Vojislava
The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most polyphagous herbivores feeding on cell contents of over 1100 plant species including more than 150 crops. It is being established as a model for chelicerate herbivores with tools that enable tracking of reciprocal responses in plant-spider mite interactions. However, despite their important pest status and a growing understanding of the molecular basis of interactions with plant hosts, knowledge of the way mites interface with the plant while feeding and the plant damage directly inflicted by mites is lacking. Here, utilizing histology and microscopy methods, we uncovered several key features of T. urticae feeding. By following the stylet path within the plant tissue, we determined that the stylet penetrates the leaf either in between epidermal pavement cells or through a stomatal opening, without damaging the epidermal cellular layer. Our recordings of mite feeding established that duration of the feeding event ranges from several minutes to more than half an hour, during which time mites consume a single mesophyll cell in a pattern that is common to both bean and Arabidopsis plant hosts. In addition, this study determined that leaf chlorotic spots, a common symptom of mite herbivory, do not form as an immediate consequence of mite feeding. Our results establish a cellular context for the plant-spider mite interaction that will support our understanding of the molecular mechanisms and cell signaling associated with spider mite feeding. PMID:27512397
Lara, Jesús R; Amrich, Ruth; Saremi, Naseem T; Hoddle, Mark S
Research on phytoseiid mites has been critical for developing an effective biocontrol strategy for suppressing Oligonchus perseae Tuttle, Baker, and Abatiello (Acari: Tetranychidae) in California avocado orchards. However, basic understanding of the spatial ecology of natural populations of phytoseiids in relation to O. perseae infestations and the validation of research-based strategies for assessing densities of these predators has been limited. To address these shortcomings, cross-sectional and longitudinal observations consisting of >3,000 phytoseiids and 500,000 O. perseae counted on 11,341 leaves were collected across 10 avocado orchards during a 10-yr period. Subsets of these data were analyzed statistically to characterize the spatial distribution of phytoseiids in avocado orchards and to evaluate the merits of developing binomial and enumerative sampling strategies for these predators. Spatial correlation of phytoseiids between trees was detected at one site, and a strong association of phytoseiids with elevated O. perseae densities was detected at four sites. Sampling simulations revealed that enumeration-based sampling performed better than binomial sampling for estimating phytoseiid densities. The ecological implications of these findings and potential for developing a custom sampling plan to estimate densities of phytoseiids inhabiting sampled trees in avocado orchards in California are discussed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Silva, Rehan; Walter, Gimme H; Wilson, Lewis J; Furlong, Michael J
We investigated the responses of 3 thrips species, Frankliniella schultzei Trybom, F. occidentalis Pergrande, and Thrips tabaci Lindeman (Thysanoptera: Thripidae) to herbivore-damaged and undamaged cotton seedlings (Gossypium hirsutum L. [Malvales: Malvaceae]) at a range of time intervals following damage by adult Tetranychus urticae (Koch), adult T. ludeni (Zacher) (Acari: Tetranychidae) or Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) larvae in olfactometer assays. The intensity/frequency of the response of thrips to herbivore-induced plants decreased with time and ultimately disappeared in all cases; however, the rate at which the response declined was related to the herbivore species that inflicted the damage. All 3 species of thrips were attracted to plants damaged by T. urticae for longer than they were to plants damaged by T. ludeni. The duration for which damaged plants remained attractive was also affected by the degree of damage inflicted on cotton seedlings. For example, F. schultzei was attracted to plants damaged by a higher density of two-spotted spider mites (100/plant) for much longer than to plants damaged by a lower density of these mites (50/plant). The results reinforce previous studies that demonstrate that arrangement of variables influences the responses of thrips to their herbivore-induced cotton host plants. Results also show that these responses are variable in time following herbivore damage to cotton plants, which further demonstrates how difficult it is to generalize about the functional significance of these interactions. © 2015 Institute of Zoology, Chinese Academy of Sciences.
Zeng, Chun-Xiang; Wang, Jin-Jun
Occasional reports linking neonicotinoid insecticide applications to field population outbreaks of the spider mite have been a topic of concern for integrated pest management programs. To elucidate the impacts of a neonicotinoid insecticide on the carmine spider mite, Tetranychus cinnabarinus Boisduval (Acari: Tetranychidae), the survivorship, reproduction, and vitellin contents of the mite were investigated after exposure to various concentrations of imidacloprid on the V. unguiculata leaf discs at 25°C, 80% RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the field-relevant dose of imidacloprid did not significantly affect the hatch rate of eggs or pre-imaginal survivorship of the mite, while sublethal doses of imidacloprid, previously determined for Myzus persicae, led to a significant increase in the hatch rate of eggs and pre-imaginal survivorship of the mite compared to the untreated control. Adult longevity and fecundity of T. cinnabarinus for imidacloprid-treated populations were slightly prolonged and increased, respectively, but the difference from the untreated control was not significant. The vitellin content in eggs increased significantly after exposure to imidacloprid. Imidacloprid may be one of the major reasons for the outbreak of T. cinnabarinus in the field. PMID:20578884
Delalibera, Italo; Hajek, Ann E; Humber, Richard A
The fungal pathogen Neozygites tanajoae Delalibera Jr., Humber & Hajek sp. nov. (Zygomycetes: Entomophthorales) is being used in Africa as a biological control agent against the introduced cassava green mite (CGM), Mononychellus tanajoa (Bondar) (Acari: Tetranychidae). This fungus is specific to CGM and has been referred to as N. floridana (Weiser & Muma) Remaud. & Keller, a common pathogen of many tetranychid mites. In the present study N. tanajoae is investigated at the morphological and molecular levels and physiological attributes of N. tanajoae and N. floridana are compared. Morphological observations of N. tanajoae isolates generally correspond to N. floridana and to other mite pathogenic species of Neozygites. However, this fungus readily can be distinguished from N. floridana based on 18S rDNA sequences, host ranges, nutritional requirements for growth in vitro, tolerances to cold (4 C) and abilities to withstand specific cryopreservation techniques. N. tanajoae isolates from Brazil and Africa have identical 18S rDNA sequences but they presented 5.7 and 9.94% pairwise distance from N. floridana isolates. N. tanajoae proved to differ sufficiently from other mite-pathogenic fungi referred to as N. floridana to justify the description of a new species.
Elliot, Sam L; Mumford, John D; de Moraes, Gilberto J; Sabelis, Maurice W
Age-specific effects of invertebrate pathogens on their hosts can greatly influence the population dynamics in such interactions. Explanations for such differences are usually sought within differing intrinsic susceptibilities of the host life stages but we present data which indicate that host size, behaviour and life history may be the overriding factors determining age-specific effects of a fungal pathogen, Neozygitesfloridana (Entomophthorales: Neozygitaceae) on spider mites (Mononychellus tanajoa Bondar, Acari: Tetranychidae). Epizootics of N. floridana in spider mites are characterised by much greater relative mortality of adult females compared with other life stages (ca. 99%), despite similar physiological susceptibilities. We present empirical data that demonstrate encounter rates of mites with N. floridana increasing with life stage during an epizootic on cassava in northeastern Brazil. Estimates of the size, walking speeds and patterns, and life history of different life stages (and adult sexes) were used to calculate expected relative encounter rates which were found not to be different from the observed values (although not testable for larvae). This helps explain the different apparent susceptibility of host life stages in the field. Given the low ecological susceptibility of younger life stages to this pathogen, we predict that the interaction time between host and pathogen, determined by climatic conditions, will be critical in determining the degree of host population control in an epizootic. We further hypothesise that such variation in ecological susceptibility to pathogens can generate selection pressures on basic host traits, contributing to the sessile nature of many microarthropods.
Kawabata, Ryuzou; Miike, Tohru; Okabe, Hirotaka; Uefune, Masayoshi; Takabayashi, Junji; Takagi, Masami; Kai, Shoichi
We performed the spectral analysis of ultraweak-photon emissions from kidney bean leaves infested by the kanzawa spider mite, Tetranychus kanzawai Kishida (Acari: Tetranychidae). We also measured the spectrum of photon emissions from artificially wounded leaves, and compared the result with spectral data obtained from the mite-infested leaves. Photon emissions from both the mite-infested and wounded leaves primarily consisted of wavelengths ranging from 500 to 700 nm, and photon intensity at these wavelengths increased steadily after perturbation. In contrast, photon intensity of the mite-infested leaves at 300-400 nm exhibited only differential changes; it began increasing at 20 h, and showed two peaks at 72 and 120 h. We previously reported that photon emissions from infested leaves might be the result of both insect damage and plant self-protection. Plant defensive responses, such as herbivore-induced plant volatiles (HIPV), are induced by insect elicitors via insect damage. Therefore, photon intensity at 500-700 nm might be related to direct injury (physiological stress), while photon intensity at 300-400 nm may signify a physiological (biochemical)-action-related defensive response.
Bensoussan, Nicolas; Santamaria, M Estrella; Zhurov, Vladimir; Diaz, Isabel; Grbić, Miodrag; Grbić, Vojislava
The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most polyphagous herbivores feeding on cell contents of over 1100 plant species including more than 150 crops. It is being established as a model for chelicerate herbivores with tools that enable tracking of reciprocal responses in plant-spider mite interactions. However, despite their important pest status and a growing understanding of the molecular basis of interactions with plant hosts, knowledge of the way mites interface with the plant while feeding and the plant damage directly inflicted by mites is lacking. Here, utilizing histology and microscopy methods, we uncovered several key features of T. urticae feeding. By following the stylet path within the plant tissue, we determined that the stylet penetrates the leaf either in between epidermal pavement cells or through a stomatal opening, without damaging the epidermal cellular layer. Our recordings of mite feeding established that duration of the feeding event ranges from several minutes to more than half an hour, during which time mites consume a single mesophyll cell in a pattern that is common to both bean and Arabidopsis plant hosts. In addition, this study determined that leaf chlorotic spots, a common symptom of mite herbivory, do not form as an immediate consequence of mite feeding. Our results establish a cellular context for the plant-spider mite interaction that will support our understanding of the molecular mechanisms and cell signaling associated with spider mite feeding.
Schmidt-Jeffris, Rebecca A; Beers, Elizabeth H; Crowder, David W
Galendromus occidentalis (Nesbitt) is an important biological control agent of spider mites (Acari: Tetranychidae) in Washington apple orchards. It was thought to be essentially the sole phytoseiid existing in this system, due in part to its resistance to commonly used orchard pesticides, and organophosphates in particular. To test this assumption, we conducted a survey of 102 commercial apple blocks in Washington to characterize the community of phytoseiid species. Seven phytoseiid species were found in our samples; G. occidentalis and Amblydromella caudiglans (Schuster) were found in the greatest abundance. We hypothesized that the gradual shift away from the use of organophosphates in recent decades may have caused the change in phytoseiid community structure. The survey data and information regarding the management, location, and surrounding habitat of each block were used to determine what factors affect phytoseiid abundances. Galendromus occidentalis abundance was positively affected by the use of conventional (vs. organic) spray programs, and the use of the acaricide bifenazate. Amblydromella caudiglans abundance was negatively affected by bifenazate use and positively affected by herbicide strip weediness; it was also less prevalent in 'Golden Delicious' blocks compared to other cultivars. These results indicate that A. caudiglans reaches higher abundances in orchards that lack certain agricultural disturbances, whereas G. occidentalis can survive in more disturbed environments. Surveys of this nature can provide valuable insight to potential drivers of community structure, allowing for the improvement of integrated pest management programs that incorporate conservation of newly recognized biological control agents such as A. caudiglans.
Alba, Juan Manuel; Montserrat, Marta; Fernández-Muñoz, Rafael
Trichome-based host plant resistance is a complex mechanism that could be used in tomato breeding to control arthropod pests. The aims of this work were to evaluate the plant traits (density of trichomes and acylsucrose production) and the functional relationships of these traits with mortality, repellence, and oviposition of Tetranychus urticae Koch (Acari: Tetranychidae). We used a population of recombinant inbred lines (RILs) derived from the cross between the wild tomato, Solanum pimpinellifolium L. 'TO-937', and the cultivated tomato, Solanum lycopersicum L. Multiple regression analyses showed that high acylsucrose content and high type-IV trichome density increased mortality and repellence, and reduced oviposition of T. urticae. Single regression analyses showed that a logistic model best explained the relationship between mortality or repellence and acylsucrose content, whereas a negative-exponential model best described the relationship between oviposition and acylsucrose content. Linear models were the best-fits for the three resistance variables with trichome IV density. Probit analysis was used to estimate acylsucrose effective doses, and revealed that 31 and 10% of the RILs produced acylsucrose above the effective doses for 90% mortality or repellence, respectively. Altogether, these results indicate that S. pimpinellifolium may be a suitable genetic source of resistance to spider mites to be used in cultivated tomato.
Chow, Andrew; Chau, Amanda; Heinz, Kevin M
Fertilization reduction could be a useful pest management tactic for floriculture crops if it reduced pest populations with little loss in crop yield and quality. We evaluated the response of the twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), to different fertilization levels for cut roses, Rosa hybrida L. 'Tropicana' and quantified fertilization effects on (1) management of T. urticae on roses, (2) abundance and distribution of T. urticae on roses, and (3) yield and quality of the cut rose crop. We tested two fertilization levels, 10% (15 ppm N) and 100% (150 ppm N) of the recommended level for commercial production, and three control methods: no control measure; a predatory mite, Phytoseiulus persimilis Athias-Henriot; and a miticide, bifenazate. Combinations of both bottom up (fertilization) and top down (biological or chemical control) tactics provided a greater degree of T. urticae control than either tactic alone. Rose productivity was reduced with fertilization at 10% of the recommended level; therefore, we conducted studies with T. urticae on roses fertilized with 33% (50 ppm N), 50% (75 ppm N), and 100% (150 ppm N) of the recommended level. Mean numbers of T. urticae and T. urticae eggs per flower shoot were twice as high on roses fertilized with 100 versus 33% or 50% of the recommended level. Number of rose leaves and total leaf area infested by T. urticae were similar at all fertilization levels. Cut rose yield and marketability were not compromised on plants fertilized with 50% of the recommended level.
Chaaban, Sameh Ben; Chermiti, Brahim; Kreiter, Serge
The date palm mite, Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae), is a serious pest of palm date fruits. Life cycle, fecundity, and longevity of this mite were studied on fruits of four date palms, Phoenix dactylifera L. (Arecales: Arecaceae)(varieties: Deglet Noor, Alig, Kentichi, and Besser), under laboratory conditions at 27 = 1 °C, 60 ± 10% RH. Total development time of immature female was shorter on Deglet Noor fruits than on the other cultivars. O. afrasiaticus on Deglet Noor had the highest total fecundity per female, while low fecundity values occurred on Besser. The comparison of intrinsic rates of natural increase (rm), net reproductive rates (Ro), and the survival rates of immature stage of O. afrasiaticus on the host plants suggests that O. afrasiaticus performs better on Deglet Noor fruits. The mite feeding on Alig showed the lowest intrinsic rate of natural population increase (rm = 0.103 day 1). The estimation of difference in susceptibility of cultivars to O. afrasiaticus is crucial for developing efficient pest control programs. Indeed, less susceptible cultivars can either be left unsprayed or sprayed at low threshold. PMID:22233420
Guzman-Valencia, S; Santillán-Galicia, M T; Guzmán-Franco, A W; González-Hernández, H; Carrillo-Benítez, M G; Suárez-Espinoza, J
Oligonychus punicae and Oligonychus perseae (Acari: Tetranychidae) are the most important mite species affecting avocado orchards in Mexico. Here we used nucleotide sequence data from segments of the nuclear ribosomal internal transcribed spacers (ITS1 and ITS2) and mitochondrial cytochrome oxidase subunit I (COI) genes to assess the phylogenetic relationships between both sympatric mite species and, using only ITS sequence data, examine genetic variation and population structure in both species, to test the hypothesis that, although both species co-occur, their genetic population structures are different in both Michoacan state (main producer) and Mexico state. Phylogenetic analysis showed a clear separation between both species using ITS and COI sequence information. Haplotype network analysis done on 24 samples of O. punicae revealed low genetic diversity with only three haplotypes found but a significant geographical population structure confirmed by analysis of molecular variance (AMOVA) and Kimura-2-parameter (K2P) analyses. In addition, a Mantel test revealed that geographical isolation was a factor responsible for the genetic differentiation. In contrast, analyses of 22 samples of O. perseae revealed high genetic diversity with 15 haplotypes found but no geographical structure confirmed by the AMOVA, K2P and Mantel test analyses. We have suggested that geographical separation is one of the most important factors driving genetic variation, but that it affected each species differently. The role of the ecology of these species on our results, and the importance of our findings in the development of monitoring and control strategies are discussed.
Al-Zyoud, Firas Ahmad
This study aimed to determine Serangium parcesetosum preference for different prey species and parasitized Bemisia tabaci (Genn.) (Hom., Aleyrodidae) by the parasitoid, Eretmocerus mundus Mercet (Hym., Aphelinidae). The results on S. parcesetosum preference by feeding on different prey species offered separately and together indicated that the predatory larvae and adults preferred significantly the cotton whitefly, B. tabaci and the castor bean whitefly, Trialeurodes ricini (Misra) (Hom., Aleyrodidae) rather than the two-spotted spider mite, Tetranychus urticae Koch (Acari, Tetranychidae); melon aphid, Aphis gossypii Glover (Hom., Aphididae) and pea leafminer, Liriomyza huidobrensis (Blanchard) (Dip., Agromyzidae). The results on S. parcesetosum preference for the whitefly species, B. tabaci and T. ricini demonstrated that there were no significant differences in the preference of both predatory larvae and adults for any whitefly species. Moreover, S. parcesetosum larvae and adults were significantly tended to avoid parasitized puparia of B. tabaci by E. mundus and fed instead on unparasitized ones. Thus, there is a feasible potential for integration the predator and the parasitoid into a biological control program to suppress B. tabaci.
Eichele-Nelson, Jaclyn L; Wick, Abbey F; DeSutter, Thomas M; Harmon, Jason P
Many environmental factors, including soil characteristics, are critical for plants, herbivorous arthropods, and their interactions. Despite increasing evidence that soil salinity drastically impacts plants, little is known about how salinity affects the herbivorous arthropod pests feeding on those plants. We investigated how soil salinity affects the twospotted spider mite (Tetranychus urticae Koch) feeding on corn (Zea mays L.) and soybean (Glycine max L.). We performed two greenhouse studies, one focusing on the impact of salinity on individual mite fecundity over a period of 3 d and the other focusing on population growth of T. urticae over 7 d. Both experiments were performed across varying salinity levels; electrical conductivity values ranged from 0.84 to 8.07 dS m-1. We also performed the 3-d fecundity experiment in the field, across naturally varying saline conditions. Overall, the twospotted spider mite performed better as salinity increased; both fecundity and population growth tended to have a positive linear correlation with salinity. These studies suggest that salinity can be important for herbivores, just as it is for plants. Moreover, the negative effects of soil salinity on crop plants in agroecosystems may be further compounded by a greater risk of pest problems. Salinity may be another important environmental stressor that can directly influence crop production while also indirectly influencing herbivorous pests. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: email@example.com.
Chemical analyses of two-spotted spider mite, Tetranychus urticae (Koch), and 3 of their host plants, Phaseolus vulgaris L., Phaseolus lunatus L., and Vigna unguiculata L. show that the content of total soluble protein, carbohydrates, and anions in the mites varies independently from the concentrat...
tapir , locality unknown, 1917, coll. E. Joukowsky). The other Paraguayan specimens of Am. triste in the USNTC, all collected in Estancia Faro Moro by...Experimental Station and Filadelfia, and has been found on cattle and horses in Villarica and on tapir in Colonia Risso (Berlese, 1888; Tonelli Rondelli, 1931
Bandaranayaka, K O; Apanaskevich, D A; Rajakaruna, R S
Nosomma monstrosum (Nuttall & Warburton) is a hard tick infesting mainly buffalo and cattle in Sri Lanka. Biological data on the life cycle pattern of N. monstrosum were collected using experimental infestation on New Zealand white rabbits under laboratory conditions. The three-host life cycle was completed within 64-102 days. Eggs hatched after 20-29 days of incubation and the larvae hatched out started feeding which lasted for 2-4 days. After a moulting period of 8-11 days nymphs emerge and they actively fed for 2-4 days. Subsequently the nymphs took 15-18 days for moulting before emerging as adults. Freshly moulted females fed for 7-8 days and remained latent for 4-5 days before starting the oviposition. Females laid 3864-12,520 eggs for 11-17 days. The male: female sex ratio was 8:3 in the adults which were moulted under laboratory conditions. Strong positive correlations were found in female weight with number of eggs laid and REI. Females raised from the first generation of eggs had higher oviposition periods, higher REI, laid ten times more eggs, and lower pre-oviposition periods compared to those collected from the wild. When a suitable host is given, N. monstrosum could successfully complete its three-host life cycle under laboratory conditions.
Bandaranayaka, K O; Apanaskevich, D A; Rajakaruna, R S
Amblyomma integrum is a hard tick infesting mainly buffalo and cattle and has been identified as an agent of human otoacariasis in Sri Lanka. Data on the life cycle pattern of A. integrum were collected by experimental infestation on New Zealand white rabbits under laboratory conditions. Wild-caught females laid 55-7389 eggs for 2-35 days after spending a latent period of 10-25 days. Egg incubation period was 31-105 days and the newly emerged larvae started feeding after 4-11 days. Larvae dropped off after feeding and they moulted into nymphs after 10-16 days. Nymphs actively fed on rabbits for 4-8 days and dropped off. Engorged nymphs took 11-25 days for moulting before emerging as adults. The male:female sex ratio of the adults moulted under laboratory conditions was 11:9. All the stages showed periodicity in engorgement and dropping off. The three-host life cycle was completed within 74-245 days with an average of 152.9 days. The mean Reproductive Efficiency Index (REI) and Reproductive Aptitude Index (RAI) were 3.6 and 1.1, respectively. Females hatched in the laboratory did not successfully feed on New Zealand white rabbits. The wild-caught females which fed on buffaloes had prolonged pre-oviposition and oviposition periods, low REI, low RAI and low eclosion under controlled laboratory conditions compared to other tick species. Although larva and nymphs of A. integrum successfully fed on New Zealand white rabbits under laboratory conditions, full life cycle was not completed because the adult females did not feed on rabbits.
Os ácaros tenuipalpídeos ou ácaros planos são importantes fitófagos constituintes do agroecossistema e florestas semitropical e tropical (JEPPSON et al., 1975; HOY, 2011), sendo que algumas espécies estão associadas à transmissão de fitovírus (CHAGAS et al., 2001 e 2003; CHILDERS et al., 2001; KITAJ...
Kwak, Mackenzie L; Mintram, Kate
A rare opportunity to travel to Herald's Beacon Islet with permission from the Australian government to collect ticks allowed for a survey of the tick fauna of the island to be undertaken for the first time. The avian fauna of the island, which serve as hosts, was also recorded and includes one new species record for the island. The seabird soft tick Ornithodoros capensis Neumann and the seabird hard tick Amblyomma loculosum Neumann were found to be present on the island. Images of the ticks present on the island are presented along with morphological characters for their identification.
Burazerović, J; Ćakić, S; Mihaljica, D; Sukara, R; Ćirović, D; Tomanović, S
Ticks parasitizing bats have been largely understudied, especially in the central part of the Balkan Peninsula, where the last data from the field research date from almost 25 years ago. Bats are hosts to a large number of ectoparasites, including ticks, which can act as vectors of zoonotic agents. For this reason, it is important to identify the distribution of ticks and their relationship to different hosts, including wild animals, bats in particular. The present research was conducted at 16 localities throughout Serbia, Montenegro, Bosnia and Herzegovina, and Former Yugoslav Republic of Macedonia (FYROM). We examined 475 individuals of bats belonging to 13 species. A total of three tick species were identified, I. simplex being the most numerous and widespread, followed by I. vespertilionis and A. vespertilionis. To the best of our knowledge, the presented data include the first records of I. simplex in Serbia and Montenegro, I. vespertilionis for Montenegro and A. vespertilionis in FYROM. Also, we identify a new possible host/parasite association between I. simplex and Rhinolophus euryale.
Two new tarsonemid species of the genus Daidalotarsonemus found on both native and crop plants in Brazil are described herein, based on adult females: Daidalotarsonemus esalqi sp. n. and Daidalotarsonemus savanicus sp. n. A key is provided to distinguish females of Daidalotarsonemus species known to...
Flat mites in the genus Raoiella have attracted recent world-wide interest due to the rapid spread of a major pest of various palm trees and other monocot species, the red palm mite, R. indica. This focus on the species R. indica has created a need to better understand the genus. Despite the econo...
Three new species of the family Rotundabaloghiidae are discovered and described from Sabah, Malaysia. The unusual Angulobaloghiarutra sp. n. differs from the other known Angulobaloghia Hirschmann, 1979 species in the long anterior process of the female's genital shield. Rotundabaloghia (Circobaloghia) tobiasisp. n. has very long and apically pilose dorsal setae and two pairs of bulbiform setae, which are unique in the subgenus Rotundabaloghia (Circobaloghia) Hirschmann, 1975. The long, serrate and curved setae in the big ventral cavity of Depressorotunda (Depressorotunda) serratasp. n. is a so far unknown character in the subgenus Depressorotunda (Depressorotunda) Kontschán, 2010.
Pence, Danny B.; Thomas, N.J.
A new species is described and additional host records are presented for 2 other species of deutonymphs of the family Hypoderatidae from the subcutaneous adipose tissues of the wood stork, Mycteria americana L. Phalacrodectes (Phalacrodectes) mycteria n. sp. appears to share affinities with species from both pelicaniform and ciconiiform hosts, but it most closely resembles P. (P.) punctatissimus (Černý) Pence & Courtney from pelicans in idiosomal chaetotaxy, cutdcular sclerotization, and posteriorly divergent, widely separated genital openings. The new species differs from this and other species of the genus by its small size, the degree of separation of the genital openings with papillae, no secondary sclerotization in the perigenital area or surrounding the genital openings, and the long filiform setae s and w on genu III. There was a mixed infection of Neottialges kutzeri Fain and N. mycteriae Pence in all of 7 wood storks examined from Florida and Georgia; P. (P) mycteria was found in 4 of these hosts. This is the 7th species described as a deutonymph in the genus Phalacrodectes. The apparent close affinity of P. (P.) mycteria with P. (P.) punctatissimus and allied species from pelicaniform versus ciconiiform birds appears to be inconsistent with the established host-parasite relationships based on classical avian taxonomic relationships. However, this apparent affinity may be more reflective of the close relationships between the families of pelicans, ibises and spoonbills, and storks as recently proposed by DNA-DNA hybridization studies.
Corn, J L; Kavanaugh, D M; Creekmore, T E; Robinson, J L
A survey was conducted to determine the status of wild mammals and birds as hosts for Amblyomma variegatum (F.) and other tick species in Antigua. Surveys of wild mammals and birds were conducted periodically from September 1988 through May 1991. Wild mammals surveyed included the small Indian mongoose (Herpestes auropunctatus Hodgson), Norway rat (Rattus norvegicus Berkenhout), and house mouse (Mus musculus L.), but only mongooses were surveyed intensively. Larvae and nymphs of A. variegatum, larvae of Boophilus microplus (Canestrini), and larvae of Ornithodoros puertoricensis (Fox) were recovered. The mean prevalences of infestation of mongooses by A. variegatum larvae and nymphs were 4.7 and 1.3%, respectively; maximums were 16.1 and 5.0%, respectively. The mean prevalence of infestation of mongooses by B. microplus was 3.2%. O. puertoricensis is reported from Antigua for the first time. The mean prevalence of infestation of mongooses by O. puertoricensis larvae was 41.2%, but seasonal prevalences ranged from 27.8 to 55.0%. Of 610 birds representing 16 species, three Carib grackles (Quiscalus lugubris Swainson) were each infested with one larva of A. variegatum.
Deloach, J R
An in vitro feeding test is described for Psoroptes ovis. The criterion for feeding response was established on the basis of coloration of mites by a red dye or by red blood cells. Feeding response was about 85% for female mites held off host cattle for 1 day. Mites preferred water plasma or serum and low-salt diets over whole blood. Feeding response was detected within 5 min of exposure to the diet, and maximum response was observed within 30 min of contact. Mites ingested an average 0.29 microliter of diet/100 mites in a single feeding. At temperatures between 10 degrees and 42 degrees C, feeding response was not significantly different.
Berger, K.A.; Ginsberg, Howard S.; Gonzalez, L.; Mather, T.N.
Laboratory studies have shown clear relationships between relative humidity (RH) and the activity and survival of Ixodes scapularis Say (blacklegged tick). However, field studies have produced conflicting results. We examined this relationship using weekly tick count totals and hourly RH observations at three field sites, stratified by latitude, within the state of Rhode Island. Records of nymphal tick abundance were compared with several RH-related variables (e.g., RH at time of sampling and mean weekly daytime RH). In total, 825 nymphs were sampled in 2009, a year of greater precipitation, with a weighted average leaf litter RH recorded at time of sampling of 85.22%. Alternatively, 649 nymphs were collected in 2010, a year of relatively low precipitation, and a weighted average RH recorded at time of sampling was 75.51%. Negative binomial regression analysis of tick count totals identified cumulative hours <82% RH threshold as a significant factor observed in both years (2009: P = 0.0037; 2010: P < 0.0001). Mean weekly daytime RH did not significantly predict tick activity in either year. However, mean weekly daytime RH recorded with 1-wk lag before sample date was a significant variable (P = 0.0016) in 2010. These results suggest a lag effect between moisture availability and patterns of tick activity and abundance. Differences in the relative importance of each RH variable between years may have been due to abnormally wet summer conditions in 2009.
Tucci, E C; Prado, A P; Araújo, R P
The development, viability, and life cycle parameters of Dermanyssus gallinae at five different temperatures (15, 20, 25, 30 and 35 degrees C), and at relative humidity 70-85% were evaluated. Life cycle duration was 690.75 h (28 days) at 15 degrees C, 263.12h (11 days) at 20 degrees C, 164.63 h (7 days) at 25 degrees C, 140.69 h (6 days) at 30 degrees C and 172.04 h (7 days) at 35 degrees C. The optimal development temperature for D. gallinae was 30 degrees C, with the greatest survival in all stages and the shortest development time. High mortality at 35 degrees C indicated that this temperature had adverse effects on development of D. gallinae, and that in field conditions D. gallinae populations may decrease or even disappear due to the negative impact of high temperature on development. There were no significant differences in the pre-oviposition period among the four temperatures 20-35 degrees C, indicating that temperature did not affect this part of the life cycle.
Tucci, Edna Clara; do Prado, Angelo P; de Araújo, Raquel Pires
The thermal requirements for development of Dermanyssus gallinae were studied under laboratory conditions at 15, 20, 25, 30 and 35 degrees C, a 12h photoperiod and 60-85% RH. The thermal requirements for D. gallinae were as follows. Preoviposition: base temperature 3.4 degrees C, thermal constant (k) 562.85 degree-hours, determination coefficient (R(2)) 0.59, regression equation: Y= -0.006035 + 0.001777x. Egg: base temperature 10.60 degrees C, thermal constant (k) 689.65 degree-hours, determination coefficient (R(2)) 0.94, regression equation: Y= -0.015367 + 0.001450x. Larva: base temperature 9.82 degrees C, thermal constant (k) 464.91 degree-hours, determination coefficient (R(2)) 0.87, regression equation: Y= -0.021123 + 0.002151x. Protonymph: base temperature 10.17 degrees C, thermal constant (k) 504.49 degree-hours, determination coefficient (R(2)) 0.90, regression equation: Y= -0.020152 + 0.001982x. Deutonymph: base temperature 11.80 degrees C, thermal constant (k) 501.11 degree-hours, determination coefficient (R(2)) 0.99, regression equation: Y= -0.023555 + 0.001996x. The results obtained showed that 15 to 42 generations of Dermanyssus gallinae may occur during the year in the State of São Paulo, as estimated based on isotherm charts. Dermanyssus gallinae may develop continually in the State of São Paulo, with a population decrease in the winter. There were differences between the developmental stages of D. gallinae in relation to thermal requirements.
Ermilov, Sergey G; Alvarado-Rodríguez, Olman; Kontschán, Jenő; Retana-Salazar, Axel P
Two species of oribatid mites of the genus Benoibates (Oribatida, Oripodidae), i.e., Benoibatesbolivianus Balogh & Mahunka, 1969(a) and Benoibatesminimus Mahunka, 1985, are recorded for the first time in Costa Rica. Both are redescribed in details, using drawings, images and SEM micrographs, on the basis of Costa Rican specimens. An identification key to the known species of Benoibates is given.
Pence, D B; Thomas, N J
A new species is described and additional host records are presented for 2 other species of deutonymphs of the family Hypoderatidae from the subcutaneous adipose tissues of the wood stork, Mycteria americana L. Phalacrodectes (Phalacrodectes) mycteria n. sp. appears to share affinities with species from both pelicaniform and ciconiiform hosts, but it most closely resembles P. (P.) punctatissimus (Cerný) Pence & Courtney from pelicans in idiosomal chaetotaxy, cuticular sclerotization, and posteriorly divergent, widely separated genital openings. The new species differs from this and other species of the genus by its small size, the degree of separation of the genital openings with papillae, no secondary sclerotization in the perigenital area or surrounding the genital openings, and the long filiform setae s and w on genu III. There was a mixed infection of Neottialges kutzeri Fain and N. mycteriae Pence in all of 7 wood storks examined from Florida and Georgia; P. (P.) mycteria was found in 4 of these hosts. This is the 7th species described as a deutonymph in the genus Phalacrodectes. The apparent close affinity of P. (P.) mycteria with P. (P.) punctatissimus and allied species from pelicaniform versus ciconiiform birds appears to be inconsistent with the established host-parasite relationships based on classical avian taxonomic relationships. However, this apparent affinity may be more reflective of the close relationships between the families of pelicans, ibises and spoonbills, and storks as recently proposed by DNA-DNA hybridization studies.
Bello, Ana Cristina P De P; Da Cunha, Arildo P; Leite, Romário C; Oliveira, Paulo R; Ribeiro, Antônio Cândido C L; Domingues, Luisa N; De Freitas, Carolina Maria V; Bastianetto, Eduardo; Dalla Rosa, Ricardo C
This trial evaluated control practices of Anocentor nitens on equines, using spraying devices and application of acaricide paste formulation in the auricular pavilion and nasal diverticulum. The study was carried out from October 2003 to March of 2008 and the evaluations had been divided in the following stages: Phase 1--out/03 mar/04 and Phases 2, 3, 4 and 5, respectively, correspondents to the month's periods until março/08. It was used score of 0 to 3 to classify infestation levels. From abr/04 to mar/06 was implanted a schedule of acaricide sprayings every seven days and divided in two series. The first one beginning in April 2004 and the second beginning in July, both using six sprayings treatments with pyrethroid chemical base--cypermethrin 0,015%, plus topical treatments applied monthly in the auricular pavilions (powder acaricide). From abril/06 to março/08 was carried out similar schedule treatments, each two months, using an experimental acaricide paste in the auricular pavilion and nasal diverticulum. Phases 2 and 3 did not showed reduction of the parasitic loads of A. nitens compared to the control period. Whereas in Phases 4 and 5 registered significant reduction compared control period and also with the results of Phases 2 and 3, characterizing the effectiveness of the treatment with the acaricide paste formulation. Results demonstrated of A. nitens populations present in the nasal diverticulum are important in the maintenance of the infestations on equines, and necessary attention to this anatomical structure when controlling ticks.
Lotfollahi, Parisa; Irani-Nejad, Karim Haddad; Khanjani, Mohamad; Moghadam, Mohamad; De Lillo, Enrico
Five species of eriophyoid mites were identified during surveys of mite fauna associated with plant species of the family Compositae from Southwest of East Azerbaijan province during 2010 and 2011. Two of them, Aceria virgatae n. sp. from Centaurea virgata Lam. and Aceria xeranthenzis n. sp. from Xeranthemumn squarrosum Boiss., were found to be new to science. No damage symptoms were observed on their host plants. Aceria xeranthemis n. sp. is the first eriophyoid collected from the plant genus Xeranthenun. Aculops centaureae (Farkas, 1960) from Centaurea albonitens Turrill and Aceria cichorii Petanović et al. 2000 from Cichorium intybus L. are new records for Iranian mite fauna. The deutogyne female of Aceria anthocoptes (Nalepa) was recorded for the first time in Iran, too. A key to the species collected on Compositae in Iran is given.
Morgan, Marjorie S.; Arlian, Larry G.; Rider, S. Dean; Grunwald, William C.; Cool, David R.
The pruritic skin disease scabies is caused by the burrowing of the itch mite Sarcoptes scabiei (De Geer). It is difficult to diagnose this disease because its symptoms often resemble those of other skin diseases. No reliable blood or molecular diagnostic test is available. The aim of this project was to begin to characterize the scabies proteome to identify scabies mite proteins, including those that may be useful in the development of a diagnostic test or vaccine. Various scabies mite extracts were separated by two-dimensional electrophoresis, and 844 Coomassie Blue-stained protein spots were excised, subjected to trypsin digestion, and analyzed by Matrix Assisted Laser Desorption/Ionization Time-Of-Flight/Time-Of-Flight (MALDI-TOF/TOF) mass spectrometry (MS). Tryptic fragment sequences determined by MS were searched against the recently completed S. scabiei annotated genome, leading to the identification of >150 proteins. Only 10 proteins hit to previously identified scabies proteins including actin, tropomyosin, and several ABC transporters. Thirteen proteins had homology to dust mite allergens (members of groups 8, 10, 13, 17, 20, 25, and 28). Most other sequences showed some homology to proteins in other mites and ticks including homologs of calmodulin, calreticulin, lipocalin, and glutathione-S-transferase. These data will now allow the identification of the proteins to which scabies patients produce antibodies, including those that may be good candidates for inclusion in a diagnostic test and vaccine. PMID:26792847
Morgan, Marjorie S; Arlian, Larry G; Rider, S Dean; Grunwald, William C; Cool, David R
The pruritic skin disease scabies is caused by the burrowing of the itch mite Sarcoptes scabiei (De Geer). It is difficult to diagnose this disease because its symptoms often resemble those of other skin diseases. No reliable blood or molecular diagnostic test is available. The aim of this project was to begin to characterize the scabies proteome to identify scabies mite proteins, including those that may be useful in the development of a diagnostic test or vaccine. Various scabies mite extracts were separated by two-dimensional electrophoresis, and 844 Coomassie Blue-stained protein spots were excised, subjected to trypsin digestion, and analyzed by Matrix Assisted Laser Desorption/Ionization Time-Of-Flight/Time-Of-Flight (MALDI-TOF/TOF) mass spectrometry (MS). Tryptic fragment sequences determined by MS were searched against the recently completed S. scabiei annotated genome, leading to the identification of >150 proteins. Only 10 proteins hit to previously identified scabies proteins including actin, tropomyosin, and several ABC transporters. Thirteen proteins had homology to dust mite allergens (members of groups 8, 10, 13, 17, 20, 25, and 28). Most other sequences showed some homology to proteins in other mites and ticks including homologs of calmodulin, calreticulin, lipocalin, and glutathione-S-transferase. These data will now allow the identification of the proteins to which scabies patients produce antibodies, including those that may be good candidates for inclusion in a diagnostic test and vaccine. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Olwoch, J M; Van Jaarsveld, A S; Scholtz, C H; Horak, I G
The suitability of present and future climates for 30 Rhipicephalus species in Africa are predicted using a simple climate envelope model as well as a Division of Atmospheric Research Limited-Area Model (DARLAM). DARLAM's predictions are compared with the mean outcome from two global circulation models. East Africa and South Africa are considered the most vulnerable regions on the continent to climate-induced changes in tick distributions and tick-borne diseases. More than 50% of the species examined show potential range expansion and more than 70% of this range expansion is found in economically important tick species. More than 20% of the species experienced range shifts of between 50 and 100%. There is also an increase in tick species richness in the south-western regions of the sub-continent. Actual range alterations due to climate change may be even greater since factors like land degradation and human population increase have not been included in this modelling process. However, these predictions are also subject to the effect that climate change may have on the hosts of the ticks, particularly those that favour a restricted range of hosts. Where possible, the anticipated biological implications of the predicted changes are explored.
Kontschán, Jenő; Friedrich, Stefan
Soil dwelling Uropodina mites were collected from a primary lowland rainforest in Amazonian Peru. The species found belong to three different families. A new diagnosis and the type genus of Tetrasejaspidae fam. nov. are given, and the family is recorded from Peru for the first time on the basis of Tetrasejaspis sellnicki Hirschmann, 1973. Two rotundabaloghid mites were collected (Rotundabaloghia (Circobaloghia) magna Hirschmann, 1992 and Rotundabaloghia (Circobaloghia) iquitosensis Hirschmann, 1992), both already reported from Peru. A new species (Origmatrachys peruensis sp. nov.) from the family Trachyuropodidae was collected in large numbers from soil, and is described on the basis of females, males, nymphs and larvae. This is the first description of the protonymphs and larvae of Origmatrachys. The new species differs from the previously described ones in the basis of sculptural pattern of dorsal, ventral, sternal shields and the length of the setae in the central part of the dorsal shield. A new key to the known adults and deutonymphs of Origmatrachys is given.
Nemati, Alireza; Mohseni, Mastaneh
This paper reports on two new species of mites of the genus Gaeolaelaps in soil from Iran, G. farajii sp. nov., and G. orbiculatus sp. nov.. A key to the species of Gaeolaelaps with short peritremes is presented.
Ermilov, Sergey G.; Alvarado-Rodríguez, Olman; Kontschán, Jenő; Retana-Salazar, Axel P.
Abstract Two species of oribatid mites of the genus Benoibates (Oribatida, Oripodidae), i.e., Benoibates bolivianus Balogh & Mahunka, 1969(a) and Benoibates minimus Mahunka, 1985, are recorded for the first time in Costa Rica. Both are redescribed in details, using drawings, images and SEM micrographs, on the basis of Costa Rican specimens. An identification key to the known species of Benoibates is given. PMID:25349489
Pence, D B; Bergan, J F
Hypopi (deutonymphs) of the family Hypoderatidae were found in a barn owl, Tyto alba (Scopoli), and a burrowing owl, Speotyto cunicularia (Molina), from Texas. A redescription is provided for mature specimens of the hypopus of Tytodectes (Tytodectes) tyto Fain from the subcutaneous adipose tissues of the pelvic region in the barn owl. The hypopus of Tytodectes (Tytodectes) speotyto n. sp. is described from specimens in the subcutaneous adipose tissues of the pelvic region and in the adipose tissues of the intermuscular fasciae of the ankle in the burrowing owl. T. (T.) speotyto appears most similar in size and chaetotaxy to T. (T.) glaucidii Cerný described from the Cuban pygmy owl, Glaucidium siju (d'Orbigny), in Cuba, but differs in the presence of a spine on tibia IV, which also occurs in T. (T.) tyto. Both of the former species have the anterior apodemes of coxae I fused in a simple V and lack a sternum. They differ from T. (T.) tyto which has the anterior apodemes of coxae I fused in a Y and there is a well developed sternum. Based on the above 3 described hypopi, the hypoderatids of owls represent an assemblage of small closely related, but easily differentiated, species. The occurrence of a few specimens of Neottialges evansi Fain in the barn owl and Hypodectes (Hypodectoides) propus (Nitzsch) in the burrowing owl probably represent examples of host capture by hypopi that normally occur in cormorants and pigeons, herons or egrets, respectively.
Mastropaolo, Mariano; Beltrán-Saavedra, L Fabián; Guglielmone, Alberto A
The tick species reported in Bolivia are reviewed here as (1) endemic or established: Ornithodoros echimys, O. guaporensis, O. hasei, O. kohlsi, O. mimon, O. peropteryx, O. rostratus, Otobius megnini, Amblyomma auricularium, A. cajennense, A. calcaratum, A. coelebs, A. dubitatum, A. humerale, A. incisum, A. longirostre, A. naponense, A. nodosum, A. oblongoguttatum, A. ovale, A. parvitarsum, A. parvum, A. pecarium, A. pseudoconcolor, A. rotundatum, A. scalpturatum, A. tigrinum, A. triste, Dermacentor nitens, Haemaphysalis juxtakochi, H. leporispalustris, I. boliviensis, I. cooleyi, I. luciae, Rhipicephalus microplus, R. sanguineus, and (2) erroneously reported: Ornithodoros puertoricensis, O. talaje, O. turicata, Amblyomma americanum, A. maculatum, A. multipunctum, Ixodes ricinus, I. scapularis, Rhipicephalus annulatus. Many of these records are lacking locality and/or host, and some of them need new findings for confirmation. Some of the species recorded may represent a threat for human and animal health, therefore would be of great value to make a countrywide survey of ticks in order to update the information presented in this work.
Warburton 1911), Haemaphysalis (Nuttall and Warburton 1915), Amblyomma (Robinson 1926) and the works of Neumann (e.g., 1899, 1901, 1911). Most of these...synonymy). Although dated, the only one of these that is of real value today is that on Amblyomma , both for its keys to the adult stages and its fine...1993 Ixodidae Amblyomma 12 Petney 1993 Aponommaa 9 Petney 1993 Boophilusb 1 Petney and Keirans 1996 Dermacentor 5 Petney and Keirans 1996 Haemaphysalis
Nava, Santiago; Beati, Lorenza; Dunlop, Jason; Guglielmone, Alberto A
Herein, Amblyomma tenellumKoch, 1844 (Ixodidae) is reestablished as a valid tick name and removed from the synonymy list of Amblyomma cajennense (Fabricius, 1787), while Amblyomma imitatorKohls, 1958, is relegated to a junior synonym of A. tenellum. Amblyomma tenellum is redescribed based on the examination of male type specimens collected by Deppe at the beginning of the 19th century in Mexico and described by Koch in 1844. Copyright © 2014 Elsevier GmbH. All rights reserved.
Ewing, S A; Mathew, J S; Panciera, R J
American canine hepatozoonosis (ACH) caused by Hepatozoon americanum Vincent-Johnson, Macintire, Lindsay, Lenz, Baneth, and Shkap is an emerging, often fatal, tick-borne protozoal disease of dogs in the United States of America. Dogs acquire infection by ingesting ticks that contain oocysts. To understand the invertebrate (definitive) host range of H. americanum, experiments were carried out using four ixodids, Rhipicephalus sanguineus (Latreille), Dermacentor variabilis Say, Amblyomma americanum (L.), and Amblyomma maculatum Koch. Laboratory-reared nymphal ticks were fed on dogs that were either naturally or experimentally infected with H. americanum; when these ticks molted to the adult stage they were either fed to susceptible dogs or were dissected and examined for the presence of oocysts. Mature H. americanum oocysts were found in >90% of A. maculatum (both males and females), whereas oocysts were not found in any of the other three species. These results confirm that A. maculatum is an excellent host and vector for H. americanum and also suggest that this apicomplexan may have a narrow invertebrate host range, at least among ixodid ticks that are likely candidate vectors in the United States.
Martínez-Girón, Rafael; Doganci, Levent; Iraola, Victor
Recently there has been an increasing interest in studying arthropods that live close to humans, such as cockroaches and mites, for their potential as vectors. Gregarines observed under light microscopy in intestinal extracts of house dust mites (Dermatophagoides spp.) are described for the first time in scientific literature.
Chen, C; Munderloh, U G; Kurtti, T J
Three new cell lines, IDE8 and IDE12 from embryos of northern specimens of Ixodes scapularis Say and ISE18 from southern specimens of I. scapularis, were compared cytogenetically via conventional karyotyping, C- and G-banding, and nucleolar organizing regions (NORs). The karyotypes were very similar. The standard karyotype in the three cell lines consisted of 28 chromosomes with 26 autosomes and XX (female) or XY (male) sex chromosomes. The X chromosome was the largest, and the Y chromosome the smallest chromosome of the karyotype. Constitutive heterochromatin (C-bands) was almost entirely restricted to the centromeric region. An additional interstitial C-band in chromosome 7 was an important notable characteristic of the three cell lines. In sets showing a similar degree of condensation, individual chromosomes of the three lines had identical G-banding patterns. In addition, there was no difference among the cells in number and position of NORs. There were approximately 100 G-bands per haploid set in chromosomes from cells in metaphase, with three to 18 G-bands in each chromosome arm. After staining with silver nitrate, interstitial NORs were identified in chromosomes 7, 10, and the X chromosome. Male cells had five and female cells had six NORs. These findings support the notion that I. scapularis and I. dammini Spielman et al. are conspecific.
Despite the economic importance of eriophyoid mites as agricultural pests, especially of cereal crops, knowledge of the eriophyoid fauna in Turkey remains incomplete. This paper presents the results of a 3-year study on grass-infesting eriophyoid mites in Turkey. The aim of this study was to collect...
Ermilov, Sergey G; Tolstikov, Andrei V
An annotated checklist of identified oribatid mites of the superfamily Galumnoidea collected from Cuba, including ten species from four genera and two families, is provided. Galumna flabellifera Hammer, 1958, Pergalumna bifissurata Hammer, 1972, Pergalumna bryani (Jacot, 1934), Pergalumna decorata Balogh & Mahunka, 1977 and Galumnopsis secunda Sellnick, 1923 are recorded for the first time in the Cuban fauna. A new species of Pergalumna, Pergalumna cubaensis sp. n., is described; it is morphologically similar to Pergalumna decorata Balogh & Mahunka, 1977, but differs from the latter by the larger body size, heavily granulated prodorsum and well-developed interlamellar setae. The adult of Allogalumna cubana Balogh & Mahunka, 1979 is redescribed.
Anderson, D L; Trueman, J W
Varroa jacobsoni was first described as a natural ectoparasitic mite of the Eastern honeybee (Apis cerana) throughout Asia. It later switched host to the Western honeybee (A. mellifera) and has now become a serious pest of that bee worldwide. The studies reported here on genotypic, phenotypic and reproductive variation among V. jacobsoni infesting A. cerana throughout Asia demonstrate that V. jacobsoni is a complex of at least two different species. In a new classification V. jacobsoni is here redefined as encompassing nine haplotypes (mites with distinct mtDNA CO-I gene sequences) that infest A. cerana in the Malaysia Indonesia region. Included is a Java haplotype, specimens of which were used to first describe V. jacobsoni at the beginning of this century. A new name, V. destructor n. sp., is given to six haplotypes that infest A. cerana on mainland Asia. Adult females of V. destructor are significantly larger and less spherical in shape than females of V. jacobsoni and they are also reproductively isolated from females of V. jacobsoni. The taxonomic positions of a further three unique haplotypes that infest A. cerana in the Philippines is uncertain and requires further study. Other studies reported here also show that only two of the 18 different haplotypes concealed within the complex of mites infesting A. cerana have become pests of A. mellifera worldwide. Both belong to V. destructor, and they are not V. jacobsoni. The most common is a Korea haplotype, so-called because it was also found parasitizing A. cerana in South Korea. It was identified on A. mellifera in Europe, the Middle East, Africa, Asia, and the Americas. Less common is a Japan/Thailand haplotype, so-called because it was also found parasitizing A. cerana in Japan and Thailand. It was identified on A. mellifera in Japan, Thailand and the Americas. Our results imply that the findings of past research on V. jacobsoni are applicable mostly to V. destructor. Our results will also influence quarantine protocols for bee mites, and may present new strategies for mite control.
Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Lee, Pei-Lung; Wu, Yin-Wen; Chung, Chien-Kung; Wang, Hsi-Chieh
Ticks are second to mosquitoes as the most important disease vectors, and recent decades have witnessed the emergence of many novel tick-borne rickettsial diseases, but systematic surveys of ticks and tick-borne rickettsioses are generally lacking in Asia. We collected and identified ticks from small mammal hosts between 2006 and 2010 in different parts of Taiwan. Rickettsia spp. infections in ticks were identified by targeting ompB and gltA genes with nested polymerase chain reaction. In total, 2,732 ticks were collected from 1,356 small mammals. Rhipicephalus haemaphysaloides Supino (51.8% of total ticks), Haemaphysalis bandicota Hoogstraal & Kohls (28.0%), and Ixodes granulatus Supino (20.0%) were the most common tick species, and Rattus losea Swinhoe (44.7% of total ticks) and Bandicota indica Bechstein (39.9%) were the primary hosts. The average Rickettsia infective rate in 329 assayed ticks was 31.9% and eight Rickettsia spp. or closely related species were identified. This study shows that rickettsiae-infected ticks are widespread in Taiwan, with a high diversity of Rickettsia spp. circulating in the ticks. Because notifiable rickettsial diseases in Taiwan only include mite-borne scrub typhus and flea-borne murine typhus, more studies are warranted for a better understanding of the real extent of human risks to rickettsioses in Taiwan.
Chen, Ze; Li, Youquan; Ren, Qiaoyun; Liu, Zhijie; Luo, Jin; Li, Kai; Guan, Guiquan; Yang, Jifei; Han, Xueqing; Liu, Guangyuan; Luo, Jianxun; Yin, Hong
Haemaphysalis bispinosa Neumann has been considered to exist in China, especially in the southern part of the country. However, H. bispinosa referred to in many Chinese research papers may in fact be H. longicornis, which is widely distributed in most regions of China. In order to clarify the occurrence of H. bispinosa, Haemaphysalis ticks collected from 18 of 23 provinces of China (Hebei, Henan, Hubei, Guangxi, Gansu, Yunnan, Xinjiang, Anhui, Zhejiang, Shannxi, Guizhou, Sichuan, Shanxi, Shandong, Ningxia, Fujian, Qinghai and Jiangxi) were examined based on morphological and molecular characteristics. We found no evidence of H. bispinosa being present in China. Our results indicate that all of the so called "H. bispinosa" ticks reported in China are in fact H. longicornis.
Ermilov, Sergey G.; Tolstikov, Andrei V.
Abstract An annotated checklist of identified oribatid mites of the superfamily Galumnoidea collected from Cuba, including ten species from four genera and two families, is provided. Galumna flabellifera Hammer, 1958, Pergalumna bifissurata Hammer, 1972, Pergalumna bryani (Jacot, 1934), Pergalumna decorata Balogh & Mahunka, 1977 and Galumnopsis secunda Sellnick, 1923 are recorded for the first time in the Cuban fauna. A new species of Pergalumna, Pergalumna cubaensis sp. n., is described; it is morphologically similar to Pergalumna decorata Balogh & Mahunka, 1977, but differs from the latter by the larger body size, heavily granulated prodorsum and well-developed interlamellar setae. The adult of Allogalumna cubana Balogh & Mahunka, 1979 is redescribed. PMID:26798237
Otranto, Domenico; Dantas-Torres, Filipe; Tarallo, Viviana Domenica; Ramos, Rafael Antonio do Nascimento; Stanneck, Dorothee; Baneth, Gad; de Caprariis, Donato
Certain tick species including Ixodes holocyclus can inoculate neurotoxins that induce a rapid, ascending flaccid paralysis in animals. Rhipicephalus sanguineus, the most widespread tick of dogs, is recognized as a vector of several pathogens causing diseases in dogs and humans. A single report suggests its role as cause of paralysis in dogs. This study presents the clinical history of 14 young dogs heavily infested by R. sanguineus (intensity of infestation, 63-328) in an endemic area of southern Italy. During May to June of 2011, dogs were presented at the clinical examination with neurological signs of different degrees (e.g., hind limb ataxia, generalized lethargy, and difficulty in movements). All animals were treated with acaricides and by manual tick removal but ten of them died within a day, displaying neurological signs. The other 4 dogs recovered within 3 days with acaricidal and supportive treatment. Twelve dogs were positive by blood smear examination for Hepatozoon canis with a high parasitemia, two also for Babesia vogeli and two were negative for hemoparasites. Low-grade thrombocytopenia, hypoalbuminemia, and pancytopenia were the haematological alterations most frequently recorded. Other causes of neurological disease in dogs were excluded and the diagnosis of tick paralysis by R. sanguineus was confirmed (ex juvantibus) by early and complete recovery of 4 dogs following acaricidal treatment and tick removal.
Raspotnig, Günther; Leutgeb, Verena; Krisper, Günther; Leis, Hans-Jörg
The chemical composition of secretions from opisthonotal (oil) glands in four species of the oribatid mite genus Oribotritia (Mixonomata, Euphthiracaroidea, Oribotritiidae) was compared by means of gas chromatography--mass spectrometry. The secretions of all, O. banksi (from North America) and three Austrian oribotritiids (O. berlesei, O. hermanni, O. storkani), are shown to be based on certain unusual compounds, the iridoid monoterpenes chrysomelidial and epi-chrysomelidial and the diterpene β-springene. These components probably represent general chemical characteristics of oribotriid oil glands. Their relative abundance in the secretions along with further components (mainly saturated and unsaturated C(13)-, C(15)-, C(17)-hydrocarbons, and the tentatively identified octadecadienal) led to well-distinguishable, species-specific oil gland secretions profiles. In addition a reduced set of "Astigmata compounds" (sensu Sakata and Norton in Int J Acarol 27:281-291, 2001)--namely the two monoterpenes neral and geranial--could be detected in extracts of O. banksi nevertheless indicating the classification of euphthiracaroids within the (monophyletic) group of "Astigmata compounds-bearing"-Oribatida. These compounds are considered to be apomorphically reduced in all Austrian species. Our findings emphasize the potential of chemosystematics using oil gland secretion profiles in the discrimination of morphologically very similar, syntopically living or even cryptic oribatid species.
Cuthbertson, Andrew G S; Mathers, James J; Croft, Pat; Nattriss, Nicola; Blackburn, Lisa F; Luo, Weiqi; Northing, Phil; Murai, Tamotsu; Jacobson, Robert J; Walters, Keith F A
Predatory mites (Amblyseius swirskii Athias-Henriot, Typhlodromips montdorensis Schicha, Neoseiulus cucumeris (Oudemans) and Iphiseius degenerans Berlese) were investigated for their potential to act as control agents for Thrips palmi Karny. Prey consumption rates and compatibility with pesticides were assessed. Second-instar larvae were the preferred life stage. Typhlodromips montdorensis consumed the most larvae (2.8) and also an average of 1.2 adult T. palmi per 5 day period. Both 24 and 48 h assessments following application of abamectin, spinosad and imazalil demonstrated mortality of predatory mites (across all species), which was significantly higher than with the other treatments (P < 0.001). Spraying with pymetrozine did not provide any increased mortality when compared with the water control. Application of thiacloprid proved detrimental only to I. degenerans. Following indirect exposure of predatory mites to pymetrozine and imazalil, no significant differences in mite mortality were obtained. Indirect exposure to spinosad was identified as the most detrimental treatment (P < 0.001) to all mites. Abamectin also proved detrimental, with only T. montdorensis showing any potential tolerance. All predatory mites investigated offer potential for controlling T. palmi. Compatibility with chemicals varied between the mites. The potential of incorporating the mites into eradication strategies for T. palmi is discussed. Copyright © 2012 Society of Chemical Industry.
Daemon, Erik; Maturano, Ralph; Monteiro, Caio Márcio de Oliveira; Goldner, Márcio Scoralik; Massoni, Tainara
The aim of this study was to assess the acaricidal activity of hydroethanolic formulations of thymol at varying concentrations on Rhipicephalus sanguineus and Dermacentor nitens larvae. The larval packet test was used and the thymol concentrations tested were 2.5, 5.0, 10.0, 15.0 and 20.0 mg/ml. The control group was exposed only to water and ethanol (50/50%) and there were 10 repetitions for each treatment. The mortality was evaluated after 24 h. For the R. sanguineus larvae, the mortality rates were 47.5, 50.2, 96.7, 95.9 and 98.1%, while for D. nitens the rates were 14.1, 75.0, 90.2, 90.3 and 99.5%, at respective thymol concentrations of 2.5, 5.0, 10.0, 15.0 and 20.0 mg/ml. The results indicate that the hydroethanolic formulations of thymol tested have acaricidal activity on R. sanguineus and D. nitens larvae exposed topically, causing mortality greater than 90% 24 h post-treatment starting at the concentration of 10 mg/ml.
Choh, Yasuyuki; van der Hammen, Tessa; Sabelis, Maurice W; Janssen, Arne
Theory on intraguild (IG) predation predicts that coexistence of IG-predators and IG-prey is only possible for a limited set of parameter values, suggesting that IG-predation would not be common in nature. This is in conflict with the observation that IG-predation occurs in many natural systems. One possible explanation for this difference might be antipredator behaviour of the IG-prey, resulting in decreased strength of IG-predation. We studied the distribution of an IG-prey, the predatory mite Neoseiulus cucumeris (Acari: Phytoseiidae), in response to cues of its IG-predator, the predatory mite Iphiseius degenerans. Shortly after release, the majority of IG-prey was found on the patch without cues of IG-predators, suggesting that they can rapidly assess predation risk. IG-prey also avoided patches where conspecific juveniles had been killed by IG-predators. Because it is well known that antipredator behaviour in prey is affected by the diet of the predator, we also tested whether IG-prey change their distribution in response to the food of the IG-predators (pollen or conspecific juveniles), but found no evidence for this. The IG-prey laid fewer eggs on patches with cues of IG-predators than on patches without cues. Hence, IG-prey changed their distribution and oviposition in response to cues of IG-predators. This might weaken the strength of IG-predation, possibly providing more opportunities for IG-prey and IG-predators to co-exist.
Szczepaniec, Adrianna; Creary, Scott F.; Laskowski, Kate L.; Nyrop, Jan P.; Raupp, Michael J.
Background Attempts to eradicate alien arthropods often require pesticide applications. An effort to remove an alien beetle from Central Park in New York City, USA, resulted in widespread treatments of trees with the neonicotinoid insecticide imidacloprid. Imidacloprid's systemic activity and mode of entry via roots or trunk injections reduce risk of environmental contamination and limit exposure of non-target organisms to pesticide residues. However, unexpected outbreaks of a formerly innocuous herbivore, Tetranychus schoenei (Acari: Tetranychidae), followed imidacloprid applications to elms in Central Park. This undesirable outcome necessitated an assessment of imidacloprid's impact on communities of arthropods, its effects on predators, and enhancement of the performance of T. schoenei. Methodology/Principal Findings By sampling arthropods in elm canopies over three years in two locations, we document changes in the structure of communities following applications of imidacloprid. Differences in community structure were mostly attributable to increases in the abundance of T. schoenei on elms treated with imidacloprid. In laboratory experiments, predators of T. schoenei were poisoned through ingestion of prey exposed to imidacloprid. Imidacloprid's proclivity to elevate fecundity of T. schoenei also contributed to their elevated densities on treated elms. Conclusions/Significance This is the first study to report the effects of pesticide applications on the arthropod communities in urban landscapes and demonstrate that imidacloprid increases spider mite fecundity through a plant-mediated mechanism. Laboratory experiments provide evidence that imidacloprid debilitates insect predators of spider mites suggesting that relaxation of top-down regulation combined with enhanced reproduction promoted a non-target herbivore to pest status. With global commerce accelerating the incidence of arthropod invasions, prophylactic applications of pesticides play a major role in
Szczepaniec, Adrianna; Raupp, Michael J.; Parker, Roy D.; Kerns, David; Eubanks, Micky D.
Background Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae), in multiple, distantly related crop plants. Methodology/Principal Findings Using cotton (Gossypium hirsutum), corn (Zea mays) and tomato (Solanum lycopersicum) plants, we show that transcription of phenylalanine amonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment. Conclusions/Significance Our findings are important because applications of neonicotinoid insecticides have been associated with outbreaks of spider mites in several unrelated plant species. More importantly, this is the first study to document insecticide-mediated disruption of plant defenses and link it to increased population growth of a non-target herbivore. This study adds to growing evidence that bioactive agrochemicals can have unanticipated ecological effects and suggests that the direct effects of insecticides on plant defenses should be considered when the ecological costs of insecticides are evaluated. PMID
Ferragut, Francisco; Navia, Denise; Ochoa, Ronald
Several mite species commonly attack cultivated citrus around the world. Up to 104 phytophagous species have been reported causing damage to leaves, buds and fruits, but only a dozen can be considered major pests requiring control measures. In recent years, several species have expanded their geographical range primarily due to the great increase in trade and travel worldwide, representing a threat to agriculture in many countries. Three spider mite species (Acari: Tetranychidae) have recently invaded the citrus-growing areas in the Mediterranean region and Latin America. The Oriental red mite, Eutetranychus orientalis (Klein), presumably from the Near East, was detected in southern Spain in 2001. The Texas citrus mite, Eutetranychus banksi (McGregor), is widely distributed in North, Central and South America. It was first reported in Europe in 1999 on citrus in Portugal; afterwards the mite invaded the citrus orchards in southern Spain. In Latin America, the Hindustan citrus mite, Schizotetranychus hindustanicus (Hirst), previously known only from citrus and other host plants in India, was reported causing significant damage to citrus leaves and fruits in Zulia, northwest Venezuela, in the late 1990s. Later, this mite species spread to the southeast being detected on lemon trees in the state of Roraima in northern Brazil in 2008. Whereas damage levels, population dynamics and control measures are relatively well know in the case of Oriental red mite and Texas citrus mite, our knowledge of S. hindustanicus is noticeably scant. In the present paper, information on pest status, seasonal trends and natural enemies in invaded areas is provided for these species, together with morphological data useful for identification. Because invasive species may evolve during the invasion process, comparison of behavior, damage and management options between native and invaded areas for these species will be useful for understanding the invader's success and their ability to
Wang, Jin-Jun; Zhang, Jian-Ping; He, Lin; Zhao, Zhi-Mo
Development, reproduction and acaricide susceptibility of Tetranychus cinnabarinus (Boisduvals) (Acari: Tetranychidae) were investigated after long-term (about 40 generations) exposure to various levels of acid rain; pH 2.5, 3.0, 4.0, and 5.6. Deionized water (pH 6.8) served as a control. The mites were reared on eggplant leaves at 28°C, 80%RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the duration of the immature stage was significantly affected by acid rain exposure. The shortest duration (8.90 days) was recorded for populations exposed to pH 5.6 acid rain, while the longest duration (9.37 days) occurred after exposure to pH 2.5 acid rain. Compared with the control population, adult longevity was shortened with an increase in acidity. Similarly, the oviposition duration was also shortened by an increase in acidity. Statistically, female fecundity did not differ significantly between pH 5.6, pH 4.0 and control populations, but did differ significantly between the control population and those exposed to pH 2.5 and pH 3.0 acid rain. This suggested that the mite suffered reproductive defects after long-term exposure to acid rain with higher acidity (pH 2.5 and 3.0). The intrinsic rate of increase among different populations was not significantly affected, but the net reproductive rate of populations exposed to pH 2.5 and 3.0 acid rain was significantly less than pH4.0, 5.6, and control populations. Bioassay results showed that after long-term exposure to acid rain, susceptibility of the mites to two acaricides, dichlorvos and fenpropathrin, did not change significantly. PMID:19537978
Woods, J L; James, D G; Lee, J C; Gent, D H
The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera: Aphididae). A 2-year study was conducted to evaluate the recommended commercial use of MeSA in hop yards in Oregon. Slow-release MeSA dispensers were stapled to supporting poles in 0.5 ha plots and these plots were compared to a paired non-treated plot on each of three farms in 2008 and 2009. Across both years, there was a trend for reduced (range 40-91%) mean seasonal numbers of T. urticae in five of the six MeSA-baited plots. Stethorus spp., key spider mite predators, tended to be more numerous in MeSA-baited plots compared to control plots on a given farm. Mean seasonal densities of hop aphid and other natural enemies (e.g., Orius spp. and Anystis spp.) were similar between MeSA-treated and control plots. Variability among farms in suppression of two-spotted spider mites and attraction of Stethorus spp. suggests that the use of MeSA to enhance CBC of spider mites in commercial hop yards may be influenced by site-specific factors related to the agroecology of individual farms or seasonal effects that require further investigation. The current study also suggests that CBC of hop aphid with MeSA in this environment may be unsatisfactory.
Hanna, Rachid; von Tiedemann, Andreas
Diagnostic PCR with two specific primer pairs (NEOSSU and 8DDC) were used to monitor the establishment and geographical distribution of Brazilian isolates of Neozygites tanajoae Delalibera, Hajek and Humber (Entomophthorales: Neozygitaceae) released in Benin for the biological control of the cassava green mite, Mononychellus tanajoa (Bondar) (Acari: Tetranychidae). A total of 141 cassava fields were visited and samples of M. tanajoa suspected to be infected by N. tanajoae were collected in 60 fields distributed between the coastal Southern Forest Mosaic (SFM) and the Northern Guinea Savanna (NGS) zones of Benin, West Africa. Analysis of DNA samples of dead mites using the species specific NEOSSU primers revealed the presence of N. tanajoae in 46 fields. The second country specific pair of primers 8DDC revealed the presence of Brazilian isolates of N. tanajoae in 36 fields, representing 78.3% of fields positive for N. tanajoae. Brazilian isolates occurred from SFM to NGS zones in Benin, however, they were concentrated in fields located within former release zones (e.g. Department of Ouémé in the South and Borgou in the North). In contrast, the indigenous African isolates of N. tanajoae were evenly distributed in the sub-humid and humid savannah zones of the country. The mean infection rate of M. tanajoa with indigenous isolates of N. tanajoae was relatively low (5.3%) compared to Brazilian isolates (28%), indicating a higher biocontrol potential of the latter. This first post-release monitoring using PCR techniques showed that the Brazilian strains of N. tanajoae is well established in Benin and spread effectively in this area. PMID:20838883
García, M; Ortego, F; Castañera, P; Farinós, G P
A laboratory study was carried out to assess the potential prey-mediated effects of Cry3Bb1-expressing Bt maize on the fitness and predatory ability of Atheta coriaria Kraatz (Coleoptera: Staphylinidae), using Tetranychus urticae Koch (Acari: Tetranychidae) as prey. The concentration of Cry3Bb1 toxin through the trophic chain significantly decreased from Bt maize (21.7 μg g(-1) FW) to mites (5.6 μg g(-1) FW) and then to A. coriaria adults (1.4 μg g(-1) FW), but not from mites to A. coriaria L1-L3 larvae (4.1-4.6 μg g(-1) FW). Interestingly, the toxin levels detected in A. coriaria larvae represent more than 20% of the concentration found in Bt maize, and the toxin was detected up to 48 h after exposure. To our knowledge, this is the highest level of exposure ever reported in a predatory beetle to the Cry3Bb1 protein. When A. coriaria larvae were reared on Bt-fed mites, Bt-free mites or rearing food, no significant differences among treatments were observed in development, morphological measurements of sclerotized structures and body weight. Moreover, no negative effects on reproductive parameters were reported in adults feeding on Bt-fed prey after 30 days of treatment, and survival was not affected after 60 days of exposure. Similarly, predatory ability and prey consumption of A. coriaria larvae and adults were not affected by exposure to the toxin. All together, these results indicate a lack of adverse effects on A. coriaria, a species commonly used as a biological control agent. The use of A. coriaria as a surrogate species for risk assessment of GM crops that express insecticidal proteins is discussed.
Agboton, Bonaventure V; Hanna, Rachid; von Tiedemann, Andreas
Diagnostic PCR with two specific primer pairs (NEOSSU and 8DDC) were used to monitor the establishment and geographical distribution of Brazilian isolates of Neozygites tanajoae Delalibera, Hajek and Humber (Entomophthorales: Neozygitaceae) released in Benin for the biological control of the cassava green mite, Mononychellus tanajoa (Bondar) (Acari: Tetranychidae). A total of 141 cassava fields were visited and samples of M. tanajoa suspected to be infected by N. tanajoae were collected in 60 fields distributed between the coastal Southern Forest Mosaic (SFM) and the Northern Guinea Savanna (NGS) zones of Benin, West Africa. Analysis of DNA samples of dead mites using the species specific NEOSSU primers revealed the presence of N. tanajoae in 46 fields. The second country specific pair of primers 8DDC revealed the presence of Brazilian isolates of N. tanajoae in 36 fields, representing 78.3% of fields positive for N. tanajoae. Brazilian isolates occurred from SFM to NGS zones in Benin, however, they were concentrated in fields located within former release zones (e.g. Department of Ouémé in the South and Borgou in the North). In contrast, the indigenous African isolates of N. tanajoae were evenly distributed in the sub-humid and humid savannah zones of the country. The mean infection rate of M. tanajoa with indigenous isolates of N. tanajoae was relatively low (5.3%) compared to Brazilian isolates (28%), indicating a higher biocontrol potential of the latter. This first post-release monitoring using PCR techniques showed that the Brazilian strains of N. tanajoae is well established in Benin and spread effectively in this area.
Wang, Jin-Jun; Zhang, Jian-Ping; He, Lin; Zhao, Zhi-Mo
Development, reproduction and acaricide susceptibility of Tetranychus cinnabarinus (Boisduvals) (Acari: Tetranychidae) were investigated after long-term (about 40 generations) exposure to various levels of acid rain; pH 2.5, 3.0, 4.0, and 5.6. Deionized water (pH 6.8) served as a control. The mites were reared on eggplant leaves at 28 degrees C, 80%RH and a photoperiod of 14:10 (L:D) in the laboratory. The results showed that the duration of the immature stage was significantly affected by acid rain exposure. The shortest duration (8.90 days) was recorded for populations exposed to pH 5.6 acid rain, while the longest duration (9.37 days) occurred after exposure to pH 2.5 acid rain. Compared with the control population, adult longevity was shortened with an increase in acidity. Similarly, the oviposition duration was also shortened by an increase in acidity. Statistically, female fecundity did not differ significantly between pH 5.6, pH 4.0 and control populations, but did differ significantly between the control population and those exposed to pH 2.5 and pH 3.0 acid rain. This suggested that the mite suffered reproductive defects after long-term exposure to acid rain with higher acidity (pH 2.5 and 3.0). The intrinsic rate of increase among different populations was not significantly affected, but the net reproductive rate of populations exposed to pH 2.5 and 3.0 acid rain was significantly less than pH 4.0, 5.6, and control populations. Bioassay results showed that after long-term exposure to acid rain, susceptibility of the mites to two acaricides, dichlorvos and fenpropathrin, did not change significantly.
Gupta, Garima; Krischik, Vera A
In many states, Japanese beetle, Popilliajaponica Newman (Coleoptera: Scarabeidae), is no longer quarantined, and management is left to professional applicators and consumers. Adult management in hybrid tea rose, Rosa L., was compared among biorational insecticides, novel imidacloprid applications (tablet, gel, and root dip), and conventional insecticides. Efficacy of biorational insecticides used by consumers varied widely and may not offer predictable management: mortality was 3.0% with Garlic Barrier, 5.0% with Monterey Neem Oil, 15.1% with Pygenic (1.4% pyrethrins), and 27.3% with Orange Guard (D-limonene). Only JB Killer (0.02% pyrethrins plus 0.2% piperonyl butoxide) had mortality of 90.9%, probably due to piperonyl butoxide. Professional biorationals did not show significant mortality: 7.7% with Azatin XL (azadirachtin) and 3.7% Conserve (spinosad). In contrast, conventional insecticides demonstrated significant mortality; 88.4% with Decathlon 20 WP (cyfluthrin) and 83.3% with Discus SC (imidacloprid plus cyfluthrin). New imidacloprid applications (tablet, gel, and root dip) worked as well as standard drench and granular methods, but they showed 9.1-42.7% mortality. However, beetles were incapacitated as demonstrated by inability to walk (82-106-s flip time) compared with controls (30-s flip time). No phytotoxicity was observed in any treatments. However, some imidacloprid treatments produced growth enhancement: higher leaf chlorophyll (1X, 3X granular, and one tablet), and larger leaf area and higher nitrogen (3X granular, drench). The highest (active ingredient) imidacloprid was in 3X granular treatment, which in an unplanned infestation, showed highest numbers of twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). Effects of imidacloprid on leaf quality and mite outbreaks deserves research.
Adango, Etienne; Onzo, Alexis; Hanna, Rachid; Atachi, Pierre; James, Braima
It is well recognized that the quality of host plants affects the development and survival of plant-feeding arthropods. The effects of two leafy vegetable crops, amaranth, Amaranthus cruentus L. (Caryophyllales: Amaranthaceae) and nightshade, Solanum macrocarpon L. (Solanales: Solanaceae) were examined on the development and demographic parameters of the spider mite, Tetranychus ludeni Zacher (Acari: Tetranychidae). This mite was recently identified as a pest of the two leafy vegetables which are widely used in West Africa. The experiments were conducted at the International Institute of Tropical Agriculture, Benin, West Africa, in a growth chamber at 27°C, 70% ±10% RH and 12:12 (L:D). Immature development of T. ludeni was shorter on A. cruentus than on S. macrocarpon, whereas female longevity was the same on the two vegetable crops. Total fecundity per female was higher on A. cruentus than on S. macrocarpon, largely due to longer survival of adult female T. ludeni on the former; however, no differences were observed in the daily fecundity of T. ludeni on the two plant species. The comparison of intrinsic rates of natural increase (rm), the net reproductive rates (Ro) and the survival rates of adult stage of T. ludeni on the two vegetable crops suggests that T. ludeni performs better on S. macrocarpon than on A. cruentus. Reasons for the lower rate of population growth observed on amaranth should be studied in more details as this could be used in IPM strategies such as intercropping to reduce pest density and in developing biopesticides for use against T. ludeni in vegetable farms in Africa.
Szczepaniec, Adrianna; Raupp, Michael J; Parker, Roy D; Kerns, David; Eubanks, Micky D
Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae), in multiple, distantly related crop plants. Using cotton (Gossypium hirsutum), corn (Zea mays) and tomato (Solanum lycopersicum) plants, we show that transcription of phenylalanine ammonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment. Our findings are important because applications of neonicotinoid insecticides have been associated with outbreaks of spider mites in several unrelated plant species. More importantly, this is the first study to document insecticide-mediated disruption of plant defenses and link it to increased population growth of a non-target herbivore. This study adds to growing evidence that bioactive agrochemicals can have unanticipated ecological effects and suggests that the direct effects of insecticides on plant defenses should be considered when the ecological costs of insecticides are evaluated.
Background Dermanyssus gallinae (poultry red mite) is a major threat for the poultry industry and is of significant interest for public health. Identification of D. gallinae can be difficult for scientists not familiar with mite morphology and terminology especially when trying to use identification keys. Moreover, this species may easily be confused with another dermanyssoid mite, Ornithonyssus sylviarum (northern fowl mite), which often shares the same hosts and environment. Methods Specimens of D. gallinae were collected at poultry farms in the Puglia and performed for light and scanning electron microscopy observations, identification and micrographs. Moreover specimens of O. sylviarum were collected separately macerated and mounted on slides for light microscopy observations, identification and pictures. Results The micrographs used in this study, based on LM and SEM observations, highlight the following important identifying characters of D. gallinae: the prominent shoulders of the dorsal shield and the jagged edges of the shield reticulations, the position of setae j1, s1 and the epigynal pores, and the presence on tibia IV pl of one seta. Additional micrographs highlighting the shape of the dorsal (abruptly narrowed posteriorly) and epigynal (narrowly rounded posteriorly) shields and the chelicera (elongate, with distinct digits) of O. sylviarum enable its differentiation from D.gallinae. Conclusion The photographic support provided here (both LM and SEM pictures) can be considered a practical tool for scientists who are not well acquainted with the morphology of D.gallinae, and who are involved with classical and molecular systematics, veterinary and human health aspects of poultry red mites. PMID:22647594
Clemente, Mateus Aparecido; de Oliveira Monteiro, Caio Márcio; Scoralik, Márcio Goldner; Gomes, Fernando Teixeira; de Azevedo Prata, Márcia Cristina; Daemon, Erik
The present study evaluated the acaricidal activity of essential oils from Eucalyptus citriodora and Cymbopogon nardus on non-engorged larvae of Amblyomma cajennense and Anocentor nitens. In order to carry out the study, six groups were formed, each concentration being a treatment (6.25%, 12.5%, 25%, and 50%, respectively) and also with the creation of a control group (distilled water) and a positive control (Deltametrine). For each treatment, approximately 100 larvae of these ticks were placed onto filter papers (2 x 2 cm) impregnated with the concentrations used to test. Next, the envelopes were closed bearing inside the filter paper with measurements of 6 x 6 cm. For each group, six repetitions were performed, and after 24 h live and dead larvae were counted. This procedure was carried out for two essential oils on the two species of ticks. For A. cajennense, the acaricide efficacy of E. citriodora oil was of 10.8%, 35.3%, 34.5%, and 53.1%, whereas the efficacy of C. nardus was of 0.0%, 0.0%, 0.0%, and 61.1% at concentrations of 6.25%, 12.5%, 25.0%, and 50.0%, respectively. In relation to A. nitens, the acaricide efficacy of E. citriodora oil was of 20.1%, 84.5%, 89.2%, and 100.0%, whereas the efficacy of C. nardus was of 0.0%, 90.8%, 100.0%, and 100.0% at concentrations of 6.25%, 12.5%, 25.0%, and 50.0%, respectively. The results indicate that the essential oils tested showed a promising acaricidal activity mainly on A. nitens larvae.
Gomes, Geovany Amorim; Monteiro, Caio Márcio Oliveira; Julião, Lisieux de Santana; Maturano, Ralph; Senra, Tatiane Oliveira Souza; Zeringóta, Viviane; Calmon, Fernanda; Matos, Renata da Silva; Daemon, Erik; Carvalho, Mario Geraldo de
The aims of this work were to identify the compounds and to investigate the acaricidal activity of the essential oil of Lippia sidoides for unengorged larvae and nymphs of Rhipicephalus sanguineus and Amblyomma cajennense. The oil was analyzed by gas chromatography and gas chromatography/mass spectrometry. In total, 22 compounds comprising 98.5% of the total peak area were identified. The major constituent of the essential oil was thymol (69.9%). The acaricidal activity against larvae and nymphs was assessed using a modified larval packet test. In all experiments, oils were tested at concentrations of 2.35, 4.70, 9.40 14.10 and 18.80 mg/mL. The mortalities of larvae and nymphs of R. sanguineus were 20.6, 47.8, 73.6, 99.5 and 99.0% and 12.0, 50.0, 76.3, 96.0 and 96.1%, respectively. For larvae and nymphs of A. cajennense the rates of mortality were 41.9, 63.3, 77.8, 82.5 and 100.0% and 0.0, 32.8, 64.8, 71.1 and 94.0%, respectively. The LC 90 values of the L. sidoides oil were 11.56 and 12.97 mg/mL for larvae and nymphs of R. sanguineus and 15.70 and 18.52 mg/mL for larvae and nymphs of A. cajennense, respectively. The essential oil from L. sidoides has acaricidal activity on unengorged larvae and nymphs of R. sanguineus and A. cajennense.
The short shoot syndrome (SSS) causes severe crop losses in Oregon vineyards due to bunch necrosis during the early part of the season. Other symptoms include malformed leaves, unusually short and angled shoots, scar tissue and bronzed leaves close to harvest time. It was determined that SSS found...
Cruz, Paula Barroso; Barbosa, Alan Franco; Zeringóta, Viviane; Melo, Diego; Novato, Tatiane; Fidelis, Queli Cristina; Fabri, Rodrigo Luiz; de Carvalho, Mário Geraldo; Oliveira Sabaa-Srur, Armando Ubirajara; Daemon, Erik; Monteiro, Caio Márcio Oliveira
We evaluated the acaricidal activity of Acmella oleracea methanol extract and spilanthol on Rhipicephalus microplus and Dermacentor nitens. The extract was made through maceration with methanol. From this extract, a dichloromethane fraction with 99% spilanthol was obtained and tested on R. microplus larvae and engorged females and D. nitens larvae. For evaluation against larvae, the modified larval packet test was used, and both the methanol extract and dichloromethane fraction were tested at concentrations of 0.2-50mg/mL. The modified larval packet test was also used in the lethal time (LT) test, with the methanol extract at a concentration of 12.5mg/mL and the percentage mortality was assessed after 15, 30, 45, 60, 75, 90, 120min and 24h. The 50% lethal time calculation (LT50) was performed in this test. The engorged female test was performed with R. microplus only, at concentrations of 25-200mg/mL for methanol extract and 2.5-20.0mg/mL for spilanthol. The methanol extract caused 100% mortality of the R. microplus and D. nitens larvae at concentrations of 3.1 and 12.5mg/mL, respectively. Spilanthol resulted in 100% mortality of R. microplus larvae at concentration of 1.6mg/mL and of D. nitens at 12.5mg/mL. In the lethal time assay using the methanol extract, the mortality rate was 100% for R. microplus and D. nitens larvae after 120min and 24h, with LT50 values of 38 and 57min, respectively. In the test of females, the egg mass weight and the hatching percentage of the groups treated with concentrations equal to or higher than 50.0mg/mL of methanol extract were significantly reduced (p<0.05), while for spilanthol, the reduction of the egg mass weight and hatching percentage occurred from concentrations of 10.0mg/mL and 2.5mg/mL, respectively. Females treated with 200.0mg/mL of extract died before starting oviposition, resulting in 100% effectiveness, while the best efficacy for spilanthol was 92.9% at a concentration of 20.0mg/mL. Thus we conclude that the methanol extract of A. oleracea and spilanthol have acaricidal activity against R. microplus and D. nitens.
Novato, Tatiane Pinheiro Lopes; Araújo, Laryssa Xavier; de Monteiro, Caio Márcio Oliveira; Maturano, Ralph; Senra, Tatiane de Oliveira Souza; da Silva Matos, Renata; Gomes, Geovany Amorim; de Carvalho, Mario Geraldo; Daemon, Erik
This study aimed at assessing the combined effect of thymol, carvacrol and (E)-cinnamaldehyde on Amblyomma sculptum and Dermacentor nitens larvae. The effects resulting from treatments were evaluated by means of the modified larval packet test. In order to determine the LC50, components of essential oils, the monoterpenes thymol, carvacrol and phenylpropanoid (E)-cinnamaldehyde were individually tested at different concentrations. After determining the LC50, each essential oil component was separately evaluated and then combined with another substance at a 1:1 proportion at the LC50 concentration and at 1/2 and 1/4 of the LC50. For A. sculptum, the lowest LC50 value was obtained for (E)-cinnamaldehyde (1.40 mg/ml), followed by thymol (2.04 mg/ml) and carvacrol (3.49 mg/ml). The same order of effectiveness was observed for D. nitens, with values of 1.68, 2.17 and 3.33 mg/ml, respectively. In the evaluation of component associations of essential oils against A. sculptum larvae, only the combinations between carvacrol and thymol (LC50) and carvacrol and (E)-cinnamaldehyde (1/4 LC50) presented a moderate synergetic effect. In turn, for D. nitens larvae, the combinations between thymol and carvacrol (LC50 and 1/2 LC50) presented a synergetic effect, while the others presented an additive or antagonistic effect. Therefore, it can be concluded that the combination of thymol and carvacrol (LC50) has a moderate synergetic effect against A. sculptum larvae, while thymol, combined with carvacrol (LC50 and 1/2 LC50), has a synergetic effect against D. nitens larvae.
Chemical composition and acaricidal activity of essential oil from Lippia sidoides on larvae of Dermacentor nitens (Acari: Ixodidae) and larvae and engorged females of Rhipicephalus microplus (Acari: Ixodidae).
Gomes, Geovany Amorim; Monteiro, Caio Márcio de Oliveira; Senra, Tatiane de Oliveira Souza; Zeringota, Viviane; Calmon, Fernanda; Matos, Renata da Silva; Daemon, Erik; Gois, Roberto Wagner da Silva; Santiago, Gilvandete Maria Pinheiro; de Carvalho, Mario Geraldo
The aim of this work was to identify the compounds and to investigate the acaricidal activity of the essential oil from the leaves of Lippia sidoides on Rhipicephalus microplus and Dermacentor nitens. The oil was obtained by hydrodistillation and analyzed by gas chromatography (GC/FID) and gas chromatography/mass spectrometry. In total, 15 compounds comprising 99.97 % of the total peak area were identified. The main constituent of the essential oil was thymol (67.60 %). The acaricidal activity was assessed by the modified larval packet test, with oil concentrations of 2.5, 5.0, 10.0, 15.0, and 20.0 μl/ml, and by the female immersion test with concentrations of 10.0, 20.0, 40.0, 60.0, and 80.0 μl/ml. The mortality of the R. microplus and D. nitens larvae was greater than 95 % starting at concentrations of 10.0 and 20.0 μl/ml, respectively. In the test with the engorged females, the L. sidoides essential oil starting at a concentration of 40.0 μl/ml caused a significant reduction (p < 0.05) in the values of the egg mass weight and egg production index. The viability of the eggs was affected in all the treated groups, with significantly lower hatching rates (p < 0.05) in relation to the control group. The control percentages at concentrations of 10.0, 20.0, and 30.0 μl/ml were 54, 57, and 72 %, and reached 100 % at the highest two concentrations (60.0 and 80.0 μl/ml). Therefore, it can be concluded that the essential oil from the leaves of L. sidoides has acaricidal activity on R. microplus and D. nitens.
Fernandez, Nestor; Theron, Pieter
Abstract Two new species of oribatid mites, Plasmobates zarae sp. n. and Basilobelba spasmenosi sp. n. are described from the Republic of Rwanda. They can easily be differentiated from other species by a number of characters. Plasmobates zarae sp. n. is differentiated the following characters. four types of particular cerotegumental layers. Integument slightly foveate to smooth on prodorsum; foveate on notogaster; ventral region rugose to smooth.Large rostral setae inserted on protuberance, whip-shaped, with longitudinal pucker; interlamellar setae rod-shaped with triangular scales; interlamellar setae small. Medial band on prodorsum extending to anterior of central part, but not reaching rostrum. Bothridium horn-shaped; opening basally incised with rectilinear wall, internal bothridial rings dentate. Sensillus whip-like, with minute triangular scales. Variably distributed circumgastric macropores. Opisthosomal gland apophysis flat, triangular in lateral view and cylindrical in posterolateral view. Six pairs of notogastral setae, all situated posterior to opisthosomal gland level. Aggenital setae not detected; three pairs of adanal setae; two pairs of anal setae present. Nymphal scalps simple without anterior tuft or filaments, with dentate peripheral ridge. Larval scalp shaped like Chinese hat. Basilobelba spasmenosi sp. n. is characterized by the combination of the following characters: Cerotegument: thick basal layer with amorphous coat and cavities of different sizes, as well as structures resembling small cauliflowers. Setation: simple: notogastral, epimeral, genital, anal; simple long, basally barbate: le, ro setae; simple, whip-shaped: ex setae; medium length, sharpened tip with thorns on surface: in setae, leg setae; Flabellate: setae situated in ventral neotrichous zone. Thorn-like barbs and more or less parallel longitudinal grooves present on body surface of le, ro, in and leg setae. Prodorsum: rostrum finger-shaped, relative sizes of setae: le > ro > in > ex. Prodorsal cuticular surface smooth with shallow transversal furrow and two oblique furrows determining two triangular structures. Large humpbacked CSO situated anterior to and in medial line with in setal insertion, dorsal bothridial opening. Notogaster swollen, hemispheric; nine pairs of minute setae, only h1, h2, h3 easily identifiable, cuticular wart and dimple clearly visible. Humeral apophysis with longitudinal furrow dorsally. Elongate chelicera with cha, chb setae, behind them a series of scales directed dorsoventrally. Epimeral setation 3-1-3-3, adanal-aggenital neotrichy with between 8-10 setae. Nymphal scalps with very particular bean-shaped structure on either side of the decoupage zone, surrounding horn-like structure. Scalps with cuticular polyhedral reticulate to ovoid structure, often forming a cavity, either completely perforated or with a thin cuticular layer resembling an interior membrane. PMID:27408588
Melathopoulos, A P; Winston, M L; Whittington, R; Higo, H; Le Doux, M
Neem oil, neem extract (neem-aza), and canola oil were evaluated for the management of the honey bee mite parasites Varroa jacobsoni (Oudemans) and Acarapis woodi (Rennie) in field experiments. Spraying neem oil on bees was more effective at controlling V. jacobsoni than feeding oil in a sucrose-based matrix (patty), feeding neem-aza in syrup, or spraying canola oil. Neem oil sprays also protected susceptible bees from A. woodi infestation. Only neem oil provided V. jacobsoni control comparable to the known varroacide formic acid, but it was not as effective as the synthetic product Apistan (tau-fluvalinate). Neem oil was effective only when sprayed six times at 4-d intervals and not when applied three times at 8-d intervals. Neem oil spray treatments had no effect on adult honey bee populations, but treatments reduced the amount of sealed brood in colonies by 50% and caused queen loss at higher doses. Taken together, the results suggest that neem and canola oil show some promise for managing honey bee parasitic mites, but the negative effects of treatments to colonies and the lower efficacy against V. jacobsoni compared with synthetic acaricides may limit their usefulness to beekeepers.
Garcia, Marcos V; Matias, Jaqueline; Aguirre, AndrÉ De A R; Csordas, Barbara G; SzabÓ, Matias P J; Andreotti, Renato
Identifying the tick species that successfully feed on humans would increase knowledge of the epidemiology of several tick-borne diseases. These species salivate into the host, increasing the risk of pathogen transmission. However, there is a lack of data in the literature regarding the ticks that prefer to feed on humans. Herein, we describe the successful feeding of Amblyomma coelebs Neumann nymphs on two of the authors after accidental tick bites occurred during field surveys in two preserved areas of Mato Grosso do Sul, Brazil. One of the host-parasite interactions was closely monitored, and the tick development, gross host skin alterations, and related sensations are presented.
Miller, R J; Davey, R B; George, J E
Two patterns of pyrethroid resistance were characterized from Boophilus microplus (Canestrini) collected in Mexico. One was characteristic of a kdr mutation and the other involved esterase and cytochrome P450 enzyme systems. Very high resistance to permethrin, cypermethrin, and flumethrin, not synergized by TPP and PBO and high resistance to DDT, characterized the kdr-like pattern found in the Corrales and San Felipe strains. Esterase and cytochrome P450-dependent resistance was found in the Coatzacoalcos strain. It was characterized by resistance to permethrin, cypermethrin, and flumethrin, synergized by TPP and PBO, but no resistance to DDT. The Coatzacoalcos strain also showed 3.6-fold resistance to the organophosphate coumaphos. This factor appeared to be independent of pyrethroid resistance. Pyrethroid resistance patterns found in Mexico were similar to those found earlier in Australia. The significance of pyrethroid and coumaphos resistance to the U.S. cattle fever tick quarantine is discussed.
Guerrero, Felix D; Li, Andrew Y; Hernandez, Ruben
Polymerase chain reaction (PCR) diagnostic assays were used to identify possible resistance-associated roles of two amino acid substitutions found in pyrethroid resistance-associated genes of Boophilus microplus (Canestrini). Individual larvae from the San Felipe target site resistant strain and the Coatzacoalcos (Cz) metabolic resistant strain were separated into resistant and susceptible groups by larval packet bioassays and analyzed by PCR. A Phe --> Ile amino acid mutation in the sodium channel gene S6 transmembrane segment of domain III was found to have a close association with survival of acaricide treatments containing as high as 30% permethrin. As the permethrin dose was increased, an increase was seen in the proportion of surviving larvae that possessed two mutated sodium channel alleles. An Asp --> Asn amino acid substitution, originally found in high allele frequency in alleles of the CzEst9 esterase of the Cz strain, appeared to provide some resistance to permethrin. However, the presence of the mutation did not associate with resistance in the dose-response fashion seen with the sodium channel amino acid mutation. Resistance provided by CzEst9 might be more dependent on concentration of CzEst9 more so than the presence of a mutated allele.