Persian Journal of Acarology

Abstract Date palm pollen has received considerable attention among various pollen types due to its high nutritional value, availability, and positive effects on predator performance. However, the nutritional quality of date palm pollen can vary significantly depending on its geographical origin. Therefore, this study was conducted to evaluate the effect of geographical variation in date palm pollen quality on the biological performance of Amblyseius swirskii Athias-Henriot. Pollen samples were collected from the same date palm cultivar (Mazafati) at four locations in southern Iran: Bam and Jiroft (Kerman Province) and Rodan and Hajiabad (Hormozgan Province). The shortest pre-adult development was observed on Rodan pollen (6.38 days), and the longest times were observed on pollen from Jiroft (7.71 days) and Bam (7.69 days). Fecundity was significantly higher in individuals fed Rodan pollen (40.62 eggs/female) than those fed other pollens. The highest pre-adult mortality occurred in individuals reared on Bam pollen, followed by Jiroft pollen. The highest intrinsic (r) and finite (λ) rates of increase were obtained on Rodan pollen (0.181 and 1.199 day-1, respectively), while the lowest values were recorded on Bam pollen (0.117 and 1.124 day-1, respectively). Similarly, Rodan pollen exhibited the highest net (R0) and gross (GRR) reproductive rates, while the lowest values were observed on Bam and Jiroft pollens. Rodan pollen had the shortest mean generation time (T) (16.45 days). Rodan pollen also had the highest protein content (43.18%), showing a significant difference compared to the other pollens. Our findings demonstrate that geographical origins of the date palm can directly affect its pollen quality and indirectly affect the biological performance of the predatory mite.

Abstract The predatory mite Amblyseius swirskii is widely used as a biological control agent against spider mites, thrips, and whiteflies. This study examined the sublethal effects of two abamectin concentrations (LC10 and LC20 for A. swirskii) on life history traits and demographic parameters of the F₁ generation derived from treated parents under controlled laboratory conditions (25 ± 1 °C, 75 ± 5% RH, 16:8 [L:D] photoperiod). Using the age-stage, two-sex life table approach with Tetranychus urticae Koch as prey, results showed that total longevity was shortest in progeny of LC20-treated parents (males = 13.42 days; females = 13.94 days) compared with LC10 progeny (males = 15.06 days; females = 15.50 days). Fecundity, oviposition period, and net reproductive rate (R₀) declined significantly with increasing acaricide concentration. Intrinsic and finite rate were reported to be increased in the treatments (r: 0.159 vs. 0.199 day−¹; λ: 1.172 vs. 1.221 day−¹). Age-specific survival (lₓ), fecundity (mₓ), and reproductive value (vₓⱼ) curves indicated pronounced adverse effects of sublethal exposure on population performance. These findings demonstrate that even low concentrations of abamectin can compromise key life history traits of A. swirskii, potentially limiting its effectiveness in biological control programs. Thus, evaluating acaricide compatibility with natural enemies is critical for successful IPM implementation.

Abstract Neoseiulus barkeri (Hughes) is a common predatory mite in the Middle East region. In the present study, the development and biological parameters of N. barkeri when preyed on Rhyncaphytoptus ficifoliae Keifer or Aceria ficus (Cotte) mite pests were investigated. The predatory mite successfully developed on R. ficifoliae and A. ficus. The pre-adult duration of N. barkeri individuals fed on A. ficus (9.24 days) was shorter than that of those reared on R. ficifoliae (10.35 days). Conversely, the egg production of N. barkeri females reared on R. ficifoliae (35.53 eggs/♀) was inferior compared to those fed on A. ficus (44.12 eggs/♀). Neoseiulus barkeri individuals reared on R. ficifoliae showed considerably lower values of intrinsic (r) and finite rates of increase (λ) (r = 0.141 day⁻¹, λ = 1.151 day⁻¹) compared to those preyed on A. ficus (r = 0.165 day⁻¹, λ = 1.179 day⁻¹). Our results suggest that N. barkeri could be considered as a potential biocontrol agent for controlling these pests.

Abstract The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is a major agricultural pest, and the predatory mite Phytoseiulus persimilis Athias-Henriot is one of its most effective natural enemies. Since temperature strongly influences predator biology, in the present study, the effects of five constant temperatures (21, 23, 25, 27, and 29 °C) on the development, survival, and reproduction of P. persimilis using age-stage and two-sex life table analysis were evaluated. Developmental time decreased with increasing temperature, while reproductive onset occurred earlier at warmer conditions. Maximum fecundity, net reproductive rate (R0 = 14.62), and intrinsic rate of increase (r = 0.35) were recorded at 25–27 °C, indicating an optimal range for population growth. However, adult longevity and reproductive performance sharply declined at 29°C, suggesting heat stress limitations. These results confirmed that P. persimilis exhibits peak biological performance at moderate temperatures (24–27°C), reinforcing its suitability as a biocontrol agent under controlled environments but highlighting reduced efficiency under extreme heat. The findings provided practical insights for optimizing mass rearing and field release strategies within integrated pest management programs.

Abstract The two-spotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae) is a significant pest of strawberries, both in greenhouse and field conditions. Research was conducted to evaluate the impact of seven different strawberry cultivars (Albion, Gaviota, Camarosa, Paros, Ventana, Sabrina, and Selva) on the life history of TSSM under laboratory conditions at 25 ± 1 ℃, 65 ± 5% RH, and a photoperiod of 16:8 (L:D). The results showed that the pre-adult duration varied significantly from 8.95 to 9.92 days, where Albion and Gaviota had the longest (9.69 and 9.92 days, respectively), while Ventana had the shortest duration (8.59 days). Female longevity was longer on Albion compared to other cultivars, but there was no significant difference among the other cultivars tested. The highest fecundity was observed on Sabrina and Gaviota (113 and 108 eggs/female, respectively), while the lowest was recorded on Paros (67.97 eggs/female). TSSM had the highest intrinsic rate of increase (r) and finite rate of increase (λ) (0.265 d⁻¹ and 1.304 d⁻¹, respectively) on Sabrina, while on Albion had the lowest ones (0.230 d⁻¹ and 1.259 d⁻¹, respectively). The results indicated that TSSM preferred Sabrina, while Albion was less favorable for this phytophagous mite. This information can be useful for designing an integrated pest management programs to control the TSSM population.

Abstract The suitability of eight pollen diets (wild almond, date palm, oak, pomegranate, pistachio, peach, damask rose, and walnut) and also Tetranychus urticae Koch as natural diet on life table of the Amblyseius swirskii (Phytoseiidae) was determined at 25 ± 1 °C, 60 ± 5% relative humidity and photoperiod of 16:8 h (L: D). Results showed that damask rose pollen was not accepted as food and did not support the development of A. swirskii beyond the protonymphal and deutonymphal stage. The highest and lowest values of the intrinsic rate of increase (r) and finite rate of increase (λ) belonged to the pistachio (0.192 and 1.212 day⁻¹) and peach (0.022 and 1.023 day⁻¹) pollen, respectively. The net reproductive rate (R₀) values varied from 1.4 offspring for the peach pollen to 29.54 offspring for the pistachio. Furthermore, the highest and lowest fecundity rate was recorded on the pistachio (36.65 eggs/female) and peach (3.23 eggs/female) pollen, respectively. Measured life table parameters of A. swirskii reared on different diets revealed pistachio, and after that, date palm and pomegranate pollen grains to be the most suitable diets. These findings may introduce more suitable pollen diets for the rearing of this predatory mite.

Abstract Macrolophus pygmaeus (Rambur) is a generalist predator that naturally colonizes and commercially is used as a biological control agent of various arthropod pests of agricultural crops. Since pesticides compatibility with natural enemies is a main concern for IPM programs, the aim of the current study was to assess the lethal and sublethal side effects of two acaricides, propargite and fenpyroximate widely used to control phytophagous mites. In bioassay experiments, M. pygmaeus adult individuals were fed on the two-spotted spider mite eggs immersed in the different concentrations of both chemicals during 24 hours. Probit analysis represented that LC₅₀ values of propargite and fenpyroximate were 3.41 and 5.74 mg (ai) L^-1, respectively. Demographic analysis performed with LC₃₀ of each acaricides using the age-stage, two-sex life table procedure. Results showed that both chemicals had significant effects on the developmental time of all stages, the total pre-oviposition period (TPOP), the adult pre-oviposition period (APOP) and females’ fecundity. Also, all main population statistics were affected by the sublethal concentrations. The intrinsic rate of increase (r) was 0.15 day^-1 in the control. However, this parameter in propargite and fenpyroximate treatments declined to 0.057 and 0.083 day^-1, respectively. The net reproductive rate (R₀) in control, propargite and fenpyroximate treated insects was 99.96, 21.16, and 71.5 offspring/individual, respectively. Mean generation time (T) in control showed 30.08 days, whilst it was 53.17, and 51.02 days in propargite and fenpyroximate sublethal treated insects, respectively. Consequently, the results achieved in this study showed that both acaricides have potential to affect the predator, adversely. Thus, they are not suitable for IPM programs in agricultural systems where this mirid bug exists as a capable biocontrol agent. 

Abstract The predatory mite, Neoseiulus barkeri Hughes is one of the most important phytoseiid mites to control phytophagous mites. The effect of different diets such as, corn pollen, walnut pollen, sunflower pollen, date pollen, bee pollen along with the two-spotted spider mite (Tetranychus urticae Koch) eggs on life table parameters of the predatory mite was determined on strawberry detached leaves in Petri dishes. The experiments were carried out under laboratory conditions at 27 ± 1°C, 16L: 8D h photo-period and 70 ± 5% RH. The individuals of  the predatory mite were collected from cucumber field infested with the two-spotted spider mite of Khoramabad, Lorestan Province. The results indicated that mean preimaginal developmental time was the highest on sunflower pollen and bee pollen than the preimaginal developmental time on the other tested pollens. The developmental time of adult of  N. barkeri when fed with bee pollen (10.0 and 9.25 days for female and male, respectively) is longer than when it fed on the other diets. The fecundity rate of predatory mite on different diets did not show any significant difference. The intrinsic rate of increase (r) of the predatory mites fed with sunflower pollen (0.212 d^-1), date pollen (0.225 d^-1) and corn pollen (0.224 d^-1) were higher than the other treatments. With attention to observed results, corn pollen, sunflower pollen and date pollen were suitable alternative food for the mass rearing of this predator.

Abstract The life history of Bryobia rubrioculus Scheuten (Acari: Tetranychidae) on sour cherry leaves was studied based on the age-stage, two-sex life table at nine constant temperatures (15, 17.5, 20, 22.5, 25, 27.5, 30, 32.5 and 33.5 ºC), 60 ± 5% RH and a photoperiod of 16: 8 (L: D) h. The longest and shortest total development time of the mites were obtained as 62.6 ± 1.66 and 14.2 ± 0.20 days at 15 and 32.5 ºC, respectively. As temperature increased from 15 to 32.5 ºC, the life span of the mites decreased from 83.5 ± 2.14 to 24.7 ± 0.39 days, respectively. The highest and lowest total fecundity was observed as 37.3 ± 1.63 and 6.3 ± 1.06 eggs at 17.5 and 15 ºC, respectively. The highest intrinsic rate of increase (r) was obtained as 0.1108 ± 0.005d^-1 at 30 ºC. The mean generation time (T) ranged from 78.1 ± 2.8 to 19.1 ± 0.2 days at 15 and 32.5 ºC. Survi-vorship data (l_x) of adult females were summarized and compared using the shape and scale parameters of the Weibull frequency distribution model. The lower temperature threshold (t) and thermal constant (k) of the immature stages were estimated using the Ikemoto and Takai linear model to be 8.9 ºC and 361.3 degree days (DD), respectively. The optimum temperatures were calculated by selected nonlinear models including Analytis1/Allahyari, Hilbert and Logan, and Logan-6 models to be 33.10, 33.90 and 32.40 ºC, respectively. 

Abstract It is well recognized that the quality of host plants affects the development and survival of herbivorous arthropods. The life table parameters of Tetranychus urticae Koch, on six cultivars of common bean (Phaseolus vulgaris L.) "chiti Khomein, chiti Ks21189, red Akhtar, red Ks31169, white Pak and white G11867" were studied at constant laboratory conditions (27±2ºC, 70±5% RH and 16 L:8 D h), during 2009–2011. Results showed that the immature developmental times of males and females were significantly influenced by bean cultivars. Tetranychus urticae laid significantly more eggs per day on red Akhtar cultivar (16.16) compared with the other cultivars. The mean generation time affected by different cultivars and it’s ranged varied from 23.37 to 34.82 days. Percentage the egg hatching of TSSM ranged varied from 88.25% to 94.20%. The highest intrinsic rate of increase (r_m), was recorded on red Akhtar (0.269±0.031day^-1) and the lowest value was obtained on white Pak (0.129±0.048day^-1). In addition, net reproductive rate (R₀) and finite rate of increase (λ) of the TSSM had the highest value on red Akhtar (62.38±1.05 female offspring and 1.30±1.02 day^-1, respectively). The lowest values of these parameters were recorded on white Pak as 27.37±1.40 female offspring and 1.13±1.10 day^-1, respectively. Doubling time (DT) varied significantly on different cultivars and its shortest and longest values were obtained on red Akhtar and white Pak, respectively. Our findings revealed that white beans (Pak and G11867) were less suitable cultivars, suggesting that they are more resistant to the TSSM than the other cultivars.

Abstract In this study, the life history and demographic parameters of Histiostoma feroniarum (Defour) on Fusarium graminearum Clade were studied under laboratory condition. The incubation, larval and nymphal periods and longevity of adults were observed to be 1.6, 2.56, 3.09 and 10.48 days, respectively. The sex ratio was 0.65. Pre-oviposition, oviposition and post-oviposition periods lasted 1.8, 8.27 and 0.66 days, respectively. The gross reproductive rate (GRR), net reproductive rate (R₀), intrinsic rate of increase (r_m), finite rate of increase (λ), mean generation time (T) and doubling time (DT) were calculated to be 110.56 females/female, 23.54 females/ female, 0.195 day^-1, 1.215 day^-1, 16.23 days and 3.55 days, respectively. The results of this study reveal high potential of H. feroniarum as a major pest of laboratory cultures.