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Mealybugs (Hemiptera: Coccomorpha: Pseudococcidae) include economically important insect pests worldwide. Pseudococcus Westwood is the second biggest genus in Pseudococcidae, with several pest species. Pseudococcus adult females were collected and identified from wild and cultivated plants in Turkey. Molecular and morphological characters were analyzed to investigate the relationship among species. It was recognized that Pseudoccoccus species are shown in three distinctive groups concerning to both morphological and molecular aspects.

Small walnut aphid (Chromaphis juglandicola(Kaltenbach) (Hemiptera: Aphididae) is important pest in walnut orchards in Lake Van Basin, Turkey. In this study, the life-table parameters reflecting population growth rate and predation rate ofChrysoperla carnea(Stephen) (Neuroptera: Chrysopidae), which is one of the important predators of the pest, were determined. Life table parameters were estimated according to age-stage, two-sex life table method. Variances and standart errors of population parameters were obtained according to Bootstrap method. The values obtained for the intrinsic rate of increase (r), finite rate of increase (lambda), net reproductive rate (R-0) and mean generation time (T) were 0.072 d(-1), 1.070 d(-1), 62.48 offspring and 57.16 d, respectively ofC. carneafed onChromaphis juglandicola. The net predation rate (C-0) was determined as 212.9 aphids. Pradation projection was performed by using timing program to prevent the predator's decrease in predation capacity and to determine the most appropriate release quantities and the appropriate interval between releases (to fill predation gaps) for biological control. The possible effects of the findings on the bio-controls ofChromaphis juglandicolabyC. carneawere discussed. Results obtained can be used in pest management program that will be prepared for this pest.

Small walnut aphid (Chromaphis juglandicola (Kaltenbach) (Hemiptera: Aphididae) is important pest in walnut orchards in Lake Van Basin, Turkey. In this study, the life-table parameters reflecting population growth rate and predation rate of Chrysoperla carnea (Stephen) (Neuroptera: Chrysopidae), which is one of the important predators of the pest, were determined. Life table parameters were estimated according to age-stage, two-sex life table method. Variances and standart errors of population parameters were obtained according to Bootstrap method. The values obtained for the intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R0) and mean generation time (T) were 0.072 d−1, 1.070 d−1, 62.48 offspring and 57.16 d, respectively of C. carnea fed on Chromaphis juglandicola. The net predation rate (C0) was determined as 212.9 aphids. Pradation projection was performed by using timing program to prevent the predator’s decrease in predation capacity and to determine the most appropriate release quantities and the appropriate interval between releases (to fill predation gaps) for biological control. The possible effects of the findings on the bio-controls of Chromaphis juglandicola by C. carnea were discussed. Results obtained can be used in pest management program that will be prepared for this pest.

Population growth parameters of the Dysaphis pyri (Boyer de Fonscolombe) (Hemiptera: Aphididae) were evaluated on four different cultivars (Coscia, Ankara, Williams, and Santa-Maria) of pear (Pyrus communis L.) under field conditions in the Van region of Turkey. Aphids were kept on leaves of 10-yr-old pear trees in Plexiglas clip-cells (20 mm in diameter and 10 mm in height, with the upper side covered with muslin). For the description of the stage differentiation during population growth, we analyzed raw data of developmental time, survival, and fecundity using the age-stage, two-sex life table to take the variable developmental rate among individuals into account. Results indicated that the Coscia and Ankara cultivars are less favorable hosts for D. pyri because of the longer preadult developmental time, higher preadult mortality rate, and lower total fecundity on these cultivars. The intrinsic rate of increase (r), the net reproduction rate (R0), and the finite rate of increase (λ) values were lower on the Coscia and Ankara cultivars. We discussed the application of the Weibull function, polynomial model, and Enkegaard model in life table studies. Because these models are often inaccurate in describing survival and reproduction parameters, we suggest that their application in life table research should be reevaluated.

To provide a comprehensive evaluation of walnut cultivar resistance to the dusky-veined walnut aphid, Panaphis juglandis (Goeze), we collected the life table data of this aphid reared on five cultivars of walnut ('Akca I,' 'Chandler,' 'Fernette,' 'Fernor,' and 'Pedro') under field conditions. The raw data of the developmental time, survival rate, and fecundity was analyzed using the age-stage, two-sex life table to account for the variable developmental rate and stage differentiation among individuals. Due to the species' longer immature developmental time, shorter adult longevity, shorter reproduction period, and lower fecundity, the net reproduction rate (R-0 = 5.9 offspring), intrinsic rate of increase (r = 0.0983 d (1)), and finite rate (lambda = 1.1034 d (1)) were the lowest when aphids were reared on the Fernor cultivar, while those reared on Akca I exhibited the highest population parameters (R-0 = 18.0 offspring, r = 0.2031 d(-1), and lambda = 1.2252 d(-1)). Based on the population characteristics, Fernor is a less favorable cultivar for the development and reproduction of P. juglandis. We also demonstrated the advantages of using bootstrapping for the analysis of standard errors of developmental time, longevity, fecundity, and other parameters as well. Our results indicated that demographic analysis of pest development, survival, and reproduction based on the agestage, two-sex life table offers a comprehensive assessment of pest growth potential on different crop cultivars.