The citrus red mite, Panonychus citri McGregor, is a key pest of different citrus species in various parts of the world. Considering the key role of resistant host plants in integrated pest management strategies, we evaluated the effects of five citrus species including grapefruit (Citrus paradisi), lime (Citrus aurantifolia), tangerine (Citrus reticulata), orange (Citrus sinensis), and sour orange (Citrus aurantium) on life table parameters of P. citri under laboratory conditions (25 ± 1°C, 65 ± 5% RH, 16:8 L:D). In addition, biochemical traits of the citrus plant species were evaluated in order to understand any possible relationship between important life history parameters with biochemical metabolites of citrus plant leaves. Phytochemicals were determined in leaf extract of citrus plant species. Various citrus species had significant effects on life history and demographical parameters of P. citri. The longest pre-adult time was observed on grapefruit (16.52 ± 0.43 days). Higher fecundity rate was on orange (15.05 ± 2.41 eggs) and tangerine (14.60 ± 3.07 eggs) and the lowest was on grapefruit (7.21 ± 2.00 eggs). The highest intrinsic rate of increase (r) was recorded as 0.071 (day−1) on tangerine, and the lowest value of this parameter was obtained on grapefruit (0.016 day−1). Significant correlations were observed between life history parameters with biochemical metabolites (carbohydrate, phenolic compounds, anthocyanin, and flavonoid). The results revealed that grapefruit was a relatively resistant host plant and tangerine was the most suitable host plant for feeding of P. citri. Our findings could be helpful for sustainable management of P. citri in citrus orchards.

Tetranychus urticae (Acari: Tetranychidae) is one of the most important pests of agricultural crops with worldwide distribution causing considerable damage to different products. Application of chemical acaricides is one of the most important strategies used for the control of this pest. Entomopathogenic fungi, however, have been proposed as alternative control agents. In this study, sub-lethal effects (LC10 = 6.76 × 102, LC20 = 8.74 × 103, and LC30 = 55.38 × 103 conidia ml−1) of Beauveria bassiana strain TV on the life table parameters of T. urticae were evaluated under laboratory conditions. The results demonstrated that by increasing the concentration, a significant decline was observed in adult longevity of both male and female individuals. Total fecundity of T. urticae was calculated as 45.16, 36.28, 23.98, and 18.21 eggs in control, LC10, LC20, and LC30 treatments, respectively. Sub-lethal concentrations drastically affected the population parameters of this mite pest. The intrinsic rate of increase (r) ranged from 0.1983 to 0.1688 day−1 for the mites treated with distilled water and LC20 treatments, respectively. The net reproductive rate (R0) was affected by the sub-lethal concentrations (lower value at LC30 concentration: 11.19 offspring/individual). Considering the detrimental effects of B. bassiana on some biological parameters of T. urticae, it can be concluded that this product can be used to develop targeted interventions aimed at integrated pest management of this pest.

Laboratory experiments were conducted to investigate the effect of diet on the biology and prédation capacity of the phytoseiid mite Amblyseius zaheri Yousef & El-Brolossy. The predatory mite was able to develop and reproduce when fed on nymphs of the twospotted spider mite Tetranychus urticae Koch, nymphs of the citrus brown mite Eutetranychus orientalis Klein, motile stages of the eriophyid mite Eriophyes dioscoridis Soliman & Abou-Awad, eggs of the scale insect Parlatorio ziziphus Lucas, nymphs of the whitefly Bemisia tabaci (Genn.) and pollen grains of date palm, Phoenix dactylifera. The predatory mite's development was fastest on a diet of nymphs of Er. dioscoridis. All of the diets led to a female-biased progeny, which was most pronounced in predators fed on date palm pollen. The results are discussed in light of the biological control capacity of the phytoseiid mite.

The unsaponifiable matter and fatty acid methyl esters of the petroleum ether extract of seven plants with known acaricidal activity were fractionated and identified by GC chromatography, and their biological activity against the two-spotted spider mite, Tetranychus urticae Koch. (Acariforms: Tetranychidae) assayed. In general, unsaponifiable matter showed higher acaricidal activity than the saponifiable matter. The unsaponifiable matter of Dodonaea viscosa leaves was the most toxic and that of Callistemon lanceolatus leaves the least toxic. The saponifiable matter (fatty acids) of Curcuma longa was the most potent.