Amblyseius Swirskii Athias-Henriot Research Articles

The impact of different photoperiod regimes on vital life traits of Amblyseius swirskii and Neoseiulus cucumeris (Acari: Phytoseiidae).

Environmental factors, such as photoperiod can play an important role in the development and performance of predatory mites. The influence of five photoperiod regimes (0: 24, 8: 16, 12: 12, 16: 8, and 24: 0h; Light: Dark) on the population parameters of the predatory mites, Amblyseius swirskii Athias-Henriot and Neoseiulus cucumeris (Oudemans) was studied under the laboratory conditions at 25°C and 25 ± 1°C, 65 ± 5% RH. Regarding A. swirskii, the longest and shortest total pre-adult and total preoviposition periods (TPOP) were in the photoperiod of 12L:12D and 16L:8D, respectively. The oviposition days, adult longevity, total life span, fecundity, gross reproductive rate (GRR), and net reproductive rate (R0) of the predator had no significant difference in all photoperiods tested. The intrinsic rate of increase (r) and the finite rate of increase (λ) in 16L:8D photoperiod had no significant difference with the other photoperiods tested except 12L:12D. Regarding N. cucumeris, the shortest total pre-adult and TPOP were in full darkness. The oviposition days and fecundity were significantly higher in 16L:8D than the others. The value of R0 in 16L:8D was significantly higher than 8L:16D. The highest values of the parameters r and λ were observed in full darkness, which had no significant difference with 16L:8D and 24L:0D. According to the results, the photoperiod regime had a more significant influence in terms of development and reproduction on N. cucumeris than A. swirskii, and 16:8 (L: D) h photoperiod was recognized as the proper regime for their rearing.

The potential application of Czenspinskia transversostriata in biological control.

Phytoseiid predatory mites are one of the most important groups of biocontrol agents, commonly used in biological control. The ability to produce these predatory mites economically, at high density on cheap factitious food sources, is a major contributor to their success. Astigmatid mites are the most widely used factitious food for this purpose. In this study, we investigated the potential application of the leaf-dwelling astigmatid mite Czenspinskia transversostriata (Oudemans) (Acari: Winterschmidtiidae) as a prey mite in biological control. We tested whether C. transversostriata is a suitable food source for the predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), both in the laboratory and on cucumber plants. Based on a reproduction trial, C. transversostriata proved to be an equally good food source compared to both pollen of Typha angustifolia L. (Poales: Typhaceae) and a frequently used prey mite Carpoglyphus lactis L. (Acari: Carpoglyphidae). In a pre-establishment trial on cucumber plants, populations of A. swirskii reached equally high densities when supplemented with C. transversostriata, compared to C. lactis. Lastly, we show that C. transversostriata is capable of feeding and reproducing on powdery mildew growing on cucumber plants, thereby slowing down the development of the pathogenic fungus. Results derived from this study show that C. transversostriata may have multiple potential applications in biological control programs.

Field efficacy of a biopesticide and a predatory mite for suppression of Scirtothrips dorsalis (Thysanoptera: Thripidae) in strawberry.

Chilli thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) has emerged as a severe invasive pest of strawberry Fragaria × ananassa Duchesne in the United States. The objective of this study was to assess the field efficacy of a biopesticide and thrips predator, Amblyseius swirskii Athias-Henriot for S. dorsalis management in field grown strawberry compared to synthetic insecticide applications that are current industry standard (spinetoram) conducted at UF/IFAS GCREC, FL during 2021-2022 and 2022-2023 in a 2-year field study. The following treatments were applied in the field: (1) biopesticide, capsicum oleoresin extract + garlic oil + canola oil application at maximum label rate; (2) predatory mite of thrips, A. swirskii released at 30 predators per plot; (3) spinetoram applied at maximum label rate; and (4) biopesticide applied 24 h before release of A. swirskii. A control plot with no insecticide or predatory mite releases was maintained. Results show that the capsicum extract can be used for management of S. dorsalis, especially during the latter stages of strawberry field season when resistance to spinetoram is high. The field performance of A. swirskii was variable and extensive research is needed to highlight factors affecting field performance of predatory mites for thrips management.

Life table parameters of Amblyseius largoensis, Amblyseius swirskii and Proprioseiopsis lenis (Acari: Phytoseiidae) fed on eggs and larvae of Frankliniella occidentalis.

The immature development and reproduction of the predatory mites Amblyseius largoensis (Muma), Proprioseiopsis lenis (Corpuz and Rimando), and Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) were investigated using both thrips eggs and first instars of the western flower thrips, Frankliniella occidentalis Pergande, as prey in a controlled laboratory environment at 25°C and 60% relative humidity. When provided with thrips eggs as food, A. largoensis exhibited a notably shorter immature development period for both males (7.05 days) and females (6.51 days) as compared with A. swirskii (8.05 and 7.19 days, respectively) and P. lenis (8.10 days and 7.05 days, respectively). Amblyseius largoensis also displayed a higher oviposition rate (2.19 eggs/female/day) than A. swirskii and P. lenis (1.79 and 1.78 eggs/female/day, respectively). Moreover, it exhibited the highest fecundity (25.34 eggs/female), followed by P. lenis (24.23 eggs/female) and A. swirskii (22.86 eggs/female). These variations led to A. largoensis having the highest intrinsic rate of increase (rm) at 0.209, followed by A. swirskii at 0.188, and P. lenis at 0.165. However, when the predatory mites were provided with first instars of F. occidentalis, A. swirskii demonstrated a faster immature development period for both males (7.67 days) and females (7.59 days) as compared with P. lenis (9.00 days and 7.86 days, respectively) and A. largoensis (8.47 days and 8.61 days, respectively). While the oviposition rates of P. lenis (1.92 eggs/female/day) and A. swirskii (1.90 eggs/female/day) were similar when feeding on this prey, A. largoensis produced fewer eggs (1.83 eggs/female/day). Further, A. swirskii exhibited the highest fecundity (31.93 eggs/female), followed by A. largoensis (25.71 eggs/female) and P. lenis (23 eggs/female). Consequently, the intrinsic rate of increase (rm) on thrips first instars was highest in A. swirskii (0.190), followed by A. largoensis (0.186), and P. lenis (0.176). In summary, our findings indicate that in terms of life history parameters A. largoensis performs optimally when feeding on thrips eggs, whereas A. swirskii performs best when preying on the mobile first instars of the thrips. These insights into the dietary preferences and reproductive capabilities of the studied predatory mite species have important implications for their potential use as biological control agents against F. occidentalis in agricultural settings.

Are predatory mites effective as biological control agents to suppress Oligonychus ilicis (Acari: Tetranychidae) in blueberry plantings?

Southern red mite, Oligonychus ilicis McGregor (Acari: Tetranychidae), is an important polyphagous spider mite pest that causes economic damage to many ornamentals, coffee, and fruit crops. Blueberry growers in the Southeastern United States, including Florida and Georgia, have experienced severe losses due to outbreaks of O. ilicis. Predatory mites are an important management tool used for controlling spider mites; however, predators have not been studied and successfully evaluated in blueberry systems. Amblyseius swirskii Athias-Henriot, Phytoseiulus persimilis Athias-Henriot, and Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) are among the most economically important arthropod agents used in augmentative biological control worldwide. To evaluate the potential of these 3 commercially available predatory mites for use in blueberry plantings, we conducted experiments under controlled laboratory conditions and in the greenhouse. In preliminary laboratory experiments, P. persimilis and N. californicus significantly reduced the number of O. ilicis motile stages below those found in the untreated control, indicating the potential for these 2 predatory mite species to suppress O. ilicis populations. Amblyseius swirskii did not perform well controlling O. ilicis motiles in the laboratory. Under greenhouse conditions, N. californicus and P. persimilis significantly reduced the number of eggs after 7 days of release and the number of motile stages after 14 days of release. This is the first report of using phytoseiid mites to suppress O. ilicis in blueberry systems in the United States. Further studies on predator behavior, feeding preferences, and acaricide compatibility with predators are required to investigate the possibility of using P. persimilis, and N. californicus as biological control agents of O. ilicis in blueberry systems.

Integration of the Generalist Predator Nabis americoferus (Hemiptera: Nabidae) in a Greenhouse Strawberry Biocontrol Program with Phytoseiid Predatory Mites and the Entomopathogenic Fungus Beauveria bassiana.

In strawberry production, western flower thrips (WFT) and two-spotted spider mites (TSSM) inflict feeding damage and reduce the yield. Biological control for these pests often includes phytoseiid predatory mites and entomopathogenic fungi. The hemipteran family Nabidae have been reported as prominent predators in open-field strawberry. Nabis americoferus Carayon is a new biocontrol agent developed in Canada. This study examined if this species was a good candidate for integration with biological control for greenhouse strawberry production. The laboratory trials showed that Phytoseiulus persimilis Athias-Henriot and Amblyseius swirskii Athias-Henriot were compatible with N. americoferus, especially when alternative food was available. In contrast, the nabid was not compatible with the Beauveria bassiana (Balsamo) GHA strain. A greenhouse cage study was conducted to determine if it was beneficial to add N. americoferus to the phytoseiid-mites-based biological control program for WFT and TSSM in greenhouse strawberry. The release of N. americoferus on a banker plant together with the placement of sachets of Neoseiulus cucumeris (Oudemans) and Neoseiulus californicus (McGregor) was beneficial, not only potentially reducing the number of sachet applications, but also providing better pest control than phytoseiid mites alone. Neither the phytoseiids nor the N. americoferus numbers were significantly affected by the presence of each other.

Field evaluation of the efficacy of copper nanoparticles against mites associated with orange trees.

Phytophagous mites are dangerous pests, causing economic losses to the world's crops. Nanotechnology is a promising field for pests and disease management, and enhancement of agricultural productivity. The aim of the study was to evaluation of the effectiveness of copper nanoparticles (CuNP) against all stages of eriophyid mite, the citrus rust mite, Phyllocoptruta oleivora (Ashmead) (Acari: Eriophyidae) and tetranychid mite, the citrus brown mite Eutetranychus orientalis (Klein) (Acari: Tetranychidae), and Tenuipalpid mite, the false spider mite, Brevipalpus obovatus Donnadieu (Acari: Tenuipalpidae). This includes its impacts on predacious mites, Amblyseius swirskii Athias-Henriot and Euseius scutalis (Athias-Henriot) (Acari: Phytoseiidae), on orange trees under field conditions. Five different concentrations of copper nanoparticles (40, 80, 160, 240, and 320 ppm), as well as the control (well water) were examined. The obtained results indicated that the mortality rate of both phytophagous and predacious mites was associated with an increase in the concentrations of copper nanoparticles. Copper nanoparticles were significantly effective in killing P. oleivora, E. orientalis and B. obovatus with minimal effects on A. swirskii and E. scutalis. The mortality percentage was 15.24, 20.32, 46.32, 78.97 and 86.37% for P. oleivora, 6.87, 9.86, 28.91, 56.30 and 77.52% for E. orientalis and 8.38, 23.50, 48.83, 68.80 and 84.08% for B. obovatus while the mortality percentage was 0.00, 0.56, 5.83, 9.91 and 15.19% for A. swirskii and 0.44, 3.96, 6.93, 8.63 and 21.39% for E. scutalis one week after exposure to 40, 80, 160, 240 and 320 ppm of copper nanoparticles, respectively. Moreover, the results showed that copper nanoparticles caused a reduction in the percentage of eggs hatching. The percentages of larvae hatching from eggs were 96.29, 80.00, 64.13, 45.66 and 32.17% for P. oleivora, 97.38, 83.28, 69.41, 48.01 and 35.29 for E. orientalis and 96.60, 76.92, 56.38, 40.55 and 33.28% for B. obovatus one week after exposure to copper nanoparticles at 40, 80, 160, 240 and 320 ppm respectively, compared with the control (well water). According to the results, the use of copper nanoparticles significant effect on reducing the population of phytophagous mites associated with orange trees, with low detrimental effects on predatory mites.

Biological aspects and life-tables of the predatory mites, Amblyseius swirskii Athias-Henriot and Neoseiulus californicus (McGregor), reared on four types of food

Biological aspects and life-tables of the predatory mites, Amblyseius swirskii Athias-Henriot and Neoseiulus californicus (McGregor), reared on four types of food

Bird-of-paradise, thorn apple and maize pollens are promising alternative diets for the long-term rearing of predatory mite Amblyseius swirskii (Acari: Phytoseiidae)

Pollen grains can provide important nutrients for reproduction of different predators such as phytoseiid mites. Since mass rearing of phytoseiid predatory mites may be facilitated by feeding on alternative diets, the current study evaluated the utility of plant pollen as diet for mass rearing of the predatory mite Amblyseius swirskii Athias-Henriot, which is a commercially available biocontrol agent of phytophagous mites and insects. Demographic parameters of A. swirskii fed on pollens of bird-of-paradise (Caesalpinia gilliesii), thorn apple (Datura stramonium), and maize (Zea mays) were determined over 10 continuous generations. In addition, the pollens of common hibiscus (Hibiscus syriacus), and velvetleaf (Abutilon theophrasti) were assessed, but the predatory mite was unable to reach adulthood when fed on these pollens, and most of them died in nymphal stages. This study also evaluated the preying ability of A. swirskii on the natural prey Tetranychus urticae Koch before and after 10 generations. All experiments were conducted in the laboratory under controlled conditions of 25±1°C, 60±5% RH, and a photoperiod of 16:8 (L: D) h. According to the life table parameters, the pollen grains of bird-of-paradise, followed by maize and thorn apple, were shown to be promising diets for the long-term rearing of A. swirskii. Furthermore, the study found that A. swirskii reared on bird-of-paradise pollen had a high predation capability, with a mean of 677 prey per generation after 10 generations. Overall, it is concluded that while bird-of-paradise pollen was the most suitable alternative diet for the predatory mite, both maize and thorn apple pollen grains were also found to be promising diets for A. swirskii. These diets can be used for mass rearing of this predatory mite.

Effects of botanical acaricides on Tetranychus urticae and compatibility with the predatory mite Amblyseius swirskii

The evaluation of biorrational products to control the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is of primary importance in the agriculture sector. In this study, we evaluated the effects of commercial botanical acaricides (BAs) on T. urticae and its predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae). In the laboratory, T. urticae was exposed to acaricide-immersed leaves and A. swirskii to acaricide-coated glass vials. In the greenhouse, potted eggplants infested with mites were sprayed with different BAs. In the laboratory, Zea mays oil-based and Glycine max oil-based BAs caused more than 95% and 80% mortality of adults after 48 h of application and caused also 100% mortality of eggs. Residual exposure of A. swirskii adults to the BAs caused 45–60% mortality. In the greenhouse, these BAs caused more than 50% decrease in the population of T. urticae for 21 d.

Influence of sub-lethal exposure to Rosmarinus officinalis L. (Lamiaceae) essential oil on demographic parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiideae)

ABSTRACT In this study, the side effects of LC30 and LC50 concentrations of Rosmarinus officinalis L. (Lamiaceae) essential oil on the life table parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) fed on first instar Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) larvae were determined under lab conditions. The age-stage, two-sex life table method was used to evaluate the life table parameters. The net reproductive rate (R0) (8.76, 8.68 and 6.83 eggs per individual), intrinsic rate of increase (r) (0.116, 0.116 and 0.098 day −1), finite rate of increase (λ) (1.123, 1.123 and 1.103 day −1), mean generation time (T) (18.7, 18.6 and 19.6 days) and total fecundity (19.77, 19.00, and 17.70 offspring per female) acquired for control, LC30 and LC50 applications, respectively. The findings of this study indicate that using the tested essential oil, particularly the LC30, in combination with A. swirskii can be an alternative to synthetic pesticides. However, semi-field and field studies are still needed to assess the effects of the essential oil tested on F. occidentalis and A. swirskii before incorporating into integrated pest management (IPM) strategies.

Modeling linear and nonlinear relationship between temperature and development rate of Amblyseuis swirskii (Acari: Phytoseiidae)

In recent years, the utilization of biocontrol agents to administer agriculture pests has received more attention, which has conduce to an growth in companies generating biocontrol agents, including predators and parasitoids. Amblyseius swirskii Athias-Henriot as a part of predatory communities in greenhouses is currently used worldwide as a biocontrol agent against small insects and various mites, especially to suppress the population of the two-spotted spider mite (TSSM), Tetranychus urticae Koch. To improve mass rearing of A. swirskii and optimize its application in integrated pest management programs, its development rate was determined at seven constant temperatures ranging from 15 to 34 (±1)°C, 50±10% RH and a photoperiod of 16:8 (L:D) h under laboratory conditions. None of the eggs hatched at 34°C and no development was observed. To determine the lower temperature threshold (T0) and thermal constant (K) of different stages of the predator, two linear models (ordinary and Ikemoto) were used. In addition, 26 nonlinear models were fitted to evaluate the development rate at different temperatures. The lower temperature threshold (T0) and thermal constant (K) of total immature stages were estimated by the ordinary (3.72°C and 133.22 DD) and Ikemoto (10.64°C and 86.51DD) linear models. Based on the Akaike information criterion (AIC), the best model for the description of the temperature-dependent development rate of the egg, larval, protonymphal, and dutonymphal stages was the Ratkowsky model and for the whole pre-adult stage, it was the Logan-6 model. Our results provided a detailed evaluation of the thermal requirements of A. swirskii, which can be important in improving the role of this mite in biological control programs.

Is UV-C light compatible with biological control of twospotted spider mite?

Biological control agents such as predatory mites, Neoseiulus cucumeris Oudemans, Amblyseius swirskii Athias-Henriot, and Phytoseiulus persimilis Athias-Henriot are effective in the management of a cosmopolitan crop pest, Tetranychus urticae Koch. Studies have shown that physical control by ultraviolet B (UV-B, 280–315 nm) light applications can control T. urticae by reducing egg hatch. However, to have a successful biological control program, the compatibility with other crop management strategies such as use of UV light needs to be determined. Therefore, the objectives of this study were to, 1) assess the impact of UV-C (200–280 nm) application on egg hatchability of biological control agents, A. swirskii, N. cucumeris, P. persimilis, and the pest T. urticae; 2) assess the impact of UV-C application on feeding efficiency of P. persimilis on T. urticae eggs; and 3) determine the LD50 and LD90 of adult female T. urticae to UV-C exposure. Results indicate that more eggs of A. swirskii survived when 200 J/m2 UV-C was used to control T. urticae, which suffered higher egg loss from the same UV-C dose. Also, UV-C treatments of 200 and 350 J/m2 did not have a significant impact on predation by P. persimilis adult females on T. urticae eggs. Therefore, UV-C can be compatibly utilized along with biological control of T. urticae by timing the application before release of predators. After 24 h of application, the UV-C LD50 for T. urticae adults was 8,839.35 J/m2 and the LD90 was 12,352.91 J/m2. After 48 h of application, the LD50 was 7,449.81 J/m2 and the LD90 was 9,621.83 J/m2. These UV-C doses are not feasible for T. urticae adult suppression, but biological control agents can play a crucial role with effective predation on T. urticae adults.

The toxic effects of some acaricides on the tomato russet mite and its predator Amblyseius swirskii Athias-Henriot, 1962 (Acari: Phytoseiidae)

The tomato russet mite, Aculops lycopersici (Massee, 1937) (Acari: Eriophyidae) is a common pest of tomatoes. The predatory mite, Amblyseius swirskii Athias-Henriot, 1962 (Acari: Phytoseiidae), can control A. lycopersici populations. To integrate biological and chemical control of A. lycopersici, side effects of the lethal concentrations of acaricides, as a predator, on A. swirskii should be considered. The lethal concentrations of 14 acaricides for A. lycopersici were determined under laboratory conditions at Bursa Uludağ University during 2017-2018. To understand the toxic impacts of the acaricides on juveniles and females of A. swirskii, the LC99 values for A. lycopersici of each acaricide were applied to A. swirskii. The reproduction reduction effects of the LC99 values were also assessed. Quite low concentrations of abamectin, milbemectin, pyridaben, azadirachtin and sulphur were found to be toxic for A. lycopersici. Based on the side effect scale, the LC99 values of abamectin, acequinocyl, bifenazate, fenproximate, fenbutatin oxide, hexythiazox, milbemectin and sulphur that killed A. lycopersici were found to be slightly toxic to both females and juveniles of A. swirskii. The results of this comparative toxicological study have showed that more field studies should be conducted to evaluate the effectiveness of using low concentrations of acaricides with A. swirskii in combination for controlling A. lycopersici.

Efficacy of single and combined release of Phytoseiulus persimilis and Amblyseius swirskii at different release ratios for control of Tetranychus urticae and Frankliniella occidentalis on rose plants

Single and combined release of Phytoseiulus persimilis Athias-Henriot and Amblyseius swirskii Athias-Henriot was tested for control of Tetranychus urticae Koch and Frankliniella occidentalis (Pergand) on rose plants. The efficacy of the predators was evaluated at predator:prey ratios of 1:2, 1:5, 1:10, 1:20, 1:50 and 1:100 in laboratory experiments, and release rates of 20, 40 and 100 predators per m2 in microcosm experiments. In all treatments, release of predator(s) significantly decreased T. urticae population and larval population of F. occidentalis compared to the control treatment. In laboratory experiment, the most suppression of T. urticae occurred in predator:prey ratios of 1:2 and 1:5 that decreased 95% and 93.5% of T. urticae after 24 h, respectively. In microcosm experiments, release rates of 100 and 40 P. persimilis per m2 eradicated (100%) the T. urticae population at 30 days after releasing the predator. Based on our findings, P. persimilis and A. swirskii can be released simultaneously at the rates of 20 and 100 individuals per m2, respectively for successful control of T. urticae and F. occidentalis on rose plants.

Foraging behaviors of Amblyseius swirskii Athias-Henriot and Euseius scutalis (Athias-Henriot) (Acari: Phytoseiidae) feed on the invasive pest, Eutetranychus orientalis (Klein) (Acari: Tetranychidae)

BackgroundRecent population outbreaks of citrus brown mite, Eutetranychus orientalis (Klein) (Acari: Tetranychidae), were observed in the Çukurova region, a region that supplies approximately 80% of total citrus production in Turkey. Therefore, to obtain preliminary data, regarding biological control of this pest, functional and numerical responses of two commonly found predatory mites, Amblyseius swirskii Athias-Henriot and Euseius scutalis (Athias-Henriot) (Phytoseiidae) in citrus orchards, to egg and protonymph stages of E. orientalis were determined under laboratory conditions.ResultsIn the experiments, six different prey densities (1, 5, 10, 20, 40 and 80) for each selected biological stage of the prey were provided to the predatory mite for 24 h. According to results, the proportion of prey consumed by A. swirskii decreased with increasing egg and protonymph stages of the prey densities. Similarly, the proportion of protonymph consumption of E. scutalis decreased with increasing prey densities, but egg consumption of the predator showed no discernible response to increasing densities. A. swirskii exhibited a type II functional response in both prey stages, whereas E. scutalis showed a type II response only for the protonymph stage of the prey. The attack rate (α) and the handling time (Th) varied between the biological stages and also predatory mite species. The highest α (0.066 h−1) and the lowest Th (0.536 h) values were determined when the A. swirskii was fed on protonymph stage of E. orientalis. The numerical response curves were found to be similar to those of Type II functional response. The efficiency of conversion of ingested food (ECI) of the both predatory mite species females decreased on both tested stages when prey density increased. The highest and the lowest average daily mean number of eggs laid by E. scutalis was found as 0.20 and 1.40 when it fed on eggs and protonymphs of its prey, respectively.ConclusionBoth predatory mite species were evaluated as potential and promising biological control agents in the sustainable control of E. orientalis in citrus orchards.

Side effects of Zataria multiflora Boiss (Lamiaceae) essential oil on predation and life table parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae)

The predatory mite, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is one of the most promising candidates for biological control of some economically important mites and insect pests such as spider mites, whiteflies, and thrips. Western Flower Thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a severe economic pest for many crops in the world. In this study the lethal concentrations of Shirazicum thymus: Zataria multiflora Boiss (Lamiaceae) essential oil was calculated to the adult stage of the WFT. Side effects LC30 and LC50 of the essential oil were assessed on life table parameters and functional response of A. swirskii. Experiments were carried out in growth chambers at 25 ± 1 °C, 60 ± 10% RH, and 16: 8 h (Light: Dark) photoperiod. We utilized the age-stage, two-sex life table method to evaluate the life history features and population growth of A. swirskii on WFT. For assessing the functional response, the first instar of WFT was offered as prey to the adult female of A. swirskii with densities of 2, 4, 8, 16, 32, and 64. The LC50 concentration of the essential oil resulted in lower fecundity (15.05 eggs/female) in comparison with the control (19.8 eggs/female). The application of LC50 and LC30 concentrations also resulted in a significant decrease in net reproductive rate (R0) (8.9, 6.6, and 4.5 eggs per individuals), intrinsic rate of increase (rm) (0.116, 0.093, and 0.077 day -1), finite rate of increase (λ) (1.123, 1.097, and 1.079 day -1), but an increase in mean generation time (T) (18.5, 20.1, and 19.5 days) (for control, LC30, and LC50, applications, respectively). A type II functional response was detected for A. swirskii fed on WFT first instar in all treatments. Adult females of A.swirskii had the highest attack rate (a) (0.11± 0.01 h-1) and shortest handling time (1.61± 0.46h) on control treatment. In conclusion, although Z. multiflora essential oil had potential against F. occidentalis to be applied in integrated pest management programs, the lethal side effects of selected essential oil on the predatory mite, A. swirskii should be considered.

Meet Amblyseius swirskii (Acari: Phytoseiidae): a commonly used predatory mite in vegetable crops

Abstract The predatory mite, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), is a generalist predator feeding on multiple soft-bodied insects and mite pest species. It is a biological control agent commercially available since 2005 that has become one of the top 3 most released biocontrol predators worldwide. It is commonly used to suppress whitefly populations (Hemiptera: Aleyrodidae), thrips (Thysanoptera), and spider mites (Acari: Tetranychidae) to a lesser degree. This predatory mite has been used as part of Integrated Pest Management (IPM) programs for vegetable (e.g., peppers, eggplants, cucumbers, squash) and ornamental (e.g., roses, chrysanthemums) crops in open fields and greenhouses, and some field crops such as cotton, but it has been demonstrated to be more successful at establishing reproductive populations and suppressing pests under protected structures. Amblyseius swirskii can feed on various food resources besides prey, including pollen or honeydew. It is successful at suppressing pests when used together with low-risk pesticides, when multiple prey are available, when prey and pollen are available naturally (neighboring flowering or companion plants present), or when pollen is supplemented in the field. This predator is a good option to control pests early in the season if shelter and food resources are available for its establishment.

Use of the generalist predator Anystis baccarum in greenhouse IPM: Interactions with other biological control agents, a laboratory study

A generalist predatory mite, Anystis baccarum (L.), was developed as a new biocontrol agent in Canada, and became commercially available in 2022. Because successful biological control programs in greenhouse crops rely on the release of several natural enemies simultaneously to deal with multiple pest species, this study assessed the interaction of A. baccarum with other commonly used biocontrol agents in laboratory trials. Note that only adult stages were used, because the agents tested are predominantly sold and released as adults. Anystis baccarum killed and consumed the generalist phytoseiid mites, Neoseiulus cucumeris (Oudemans) and Amblyseius swirskii Athias-Henriot; however, the mortality of the phytoseiid mites was reduced when an alternative food, Ephestia kuehniella Zeller eggs, was available. There was no intra-guild interaction between A. baccarum and the soil-dwelling predatory mite, Stratiolaelaps scimitus (Womersley). No statistically significant mortality was observed when Orius insidiosus (Say), a generalist hemipteran, or Delphastus catalinae (Horn), a coccinelid beetle used to control whiteflies, were confined with A. baccarum without alternative food for 24 h. The susceptibility of A. baccarum to the entomopathogenic fungus Beauveria bassiana (Balsamo) GHA strain was evaluated by exposing the mites to conidia in a filter paper bioassay. Differences in mite mortality were not significant across all treatments, and only one case of successful sporulation fungal growth was observed from cadavers recovered in the experiments; similarly, differences in the number of eggs produced were not significant across all treatments. Although the laboratory trials sometimes showed severe predation pressure from A. baccarum on other biocontrol agents, they are likely to be functionally compatible in the greenhouse owing to differences in habitat preferences and availability of other prey (pests) or another food source. Results of the current study provide insights that will enable the development of rational biocontrol programs that include A. baccarum.

Generation-dependent demography and predation capacity of Amblyseius swirskii (Acari: Phytoseiidae) fed on saffron pollen

ABSTRACT Using alternative food for mass rearing of phytoseiid predatory mites may facilitate their cost-effective production. Demographic parameters of Amblyseius swirskii Athias-Henriot fed on saffron (Crocus sativus) pollen was determined over 20 continuous generations. Furthermore, the ability of A. swirskii to consume the natural prey Tetranychus urticae Koch after the first, 10th and 20th generations was evaluated. The longest (7.40 d) and shortest (6.18 d) development time occurred in the first and 10th generations, respectively. Females at the 10th generation laid their eggs earlier (after 2.63 days) and also had higher fecundity (49.46 eggs) compared with other generations. The gross reproductive rate (GRR), net reproductive rate (R 0), intrinsic rate of increase (r) and finite rate of increase (λ) of A. swirskii remained stable during different generations. Furthermore, the results of this study revealed that the values of r, GRR and λ were not significantly affected by the generation. The net predation rate (C 0), and finite predation rate (ω) of this predator in 20th generation was significantly higher than the first and 10th generations, which represents high predation capability of the predator after rearing on pollen for a long time. Finally, it can be concluded that saffron pollen maintained a proper performance of A. swirskii up to 20 generations and this alternative diet can be used for mass rearing of this predatory mite.