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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.

Vermisüspansiyon yenilikçi organik kontrol önlemleri, toprak solucanları ve çeşitli mikroorganizmalar aracılığı ile bitki gelişimini teşvik eden, verimi arttıran, pahalı olmayan, bu nedenle organik ürün yetiştirme alanlarında tercih edilen yöntemlerden biridir. Bu çalışmada iki farklı vermisüspansiyon uygulamasının biber bitkisi üzerinde beslenen Myzus (N.) persicae Sulzer (Hemiptera: Aphididae)‘nin gelişim parametreleri üzerindeki etkileri, iklim odalarında 25±10 oC, %60±5 orantılı nem ve 16:8 aydınlık-karanlık koşullarında test edilmiştir. Vermisüspansiyonlar 1/100 oranında seyreltilerek, saksılara içirme yöntemi ile uygulanmıştır. Yaş ve döneme bağlı iki eşeyli yaşam çizelgesi analizi ile yaşam çizelgesi parametreleri oluşturulmuştur. Çalışma sonucunda iki farklı vermisüspansiyon (VS1 ve VS2) uygulaması arasında önemli bir fark bulunmazken, VS1 uygulamasının kontrol uygulamasına göre daha etkili olduğu görülmüştür. VS1 uygulanmış bitkiler üzerinde elde edilen net üreme gücü (R0,) (30.87 döl/birey), kalıtsal üreme yeteneği (r) (0.2145 gün-1) ve üreme gücü sınırı (λ) (1.2393 gün-1) değerleri kontrol bitkileri üzerinde elde edilenden daha düşük bulunmuştur.

Green peach aphid (Myzus persicae Sulzer (Aphididae: Hemiptera)) is a polyphagous pest that causes economic losses in the tobacco. In addition to general aphid damage, it is a vector for important viral diseases in tobacco. Fertilization methods, which are used to increased soil fertility, in the plant growing phase, contribute significantly to the optimal physical, chemical and biological properties of the soil, which allows the plants grown in that soil to be more resistant to diseases and pests. Therefore, in this study, the effects of liquid vermicompost and synthetic fertilizer applications on the development and biological parameters of green peach aphids were investigated in comparison with the control. The experiments were carried out under controlled climate chambers. Life table parameters were obtained using the data obtained for the development and reproduction of the aphids. In the study, while there was no statistically significant difference between population parameters, both treatments were found to suppress the pest populations compared to the control application. This application can be used as an ecological control method for the pest.

Ceviz küçük yaprakbiti (Chromaphis juglandicola (Kalt.) (Hem.:Aphididae) ve ceviz yeşil yaprakbiti (Panaphis juglandis) (Goeze) (Hemiptera: Callaphididae) Van gölü havzasındaki önemli ceviz zararlılarıdır. Ceviz yaprağının alt ve üst kısmında ayrı kolonize olan yaprakbitleri, popülasyonlarının yoğun olması durumunda ceviz de kalite ve kantite kayıplarına neden olurlar. Bu çalışmada, zararlıların biyolojik mücadelesine yönelik, en önemli avcılarından biri olan Chrysoperla carnea (Stephen) (Neuroptera: Chrysopidae)‘nın her iki yaprakbiti ile beslenmesine dayalı popülasyon büyüme oranı parametreleri belirlenmiştir. Denemeler 25±10°C, %65±5 nem ve 16:8 (L:D) h (5.000 lüks) ışıklanma süresi koşullarındaki iklim odalarında gerçekleştirilmiştir. Yaşam çizelgesi parametreleri yaş ve döneme bağlı iki eşeyli yaşam çizelgesi yöntemine göre hesaplanmıştır. Chromaphis juglandicola ve Panaphis juglandis ile beslenen C. carnea‘nın kalıtsal üreme yeteneği (r), Üreme gücü sınırı (λ), net üreme gücü (R0) ve ortalama döl süresi (T) sırasıyla 0,082 gün-1, 1,082 gün-1, 59,47 yumurta/generasyon ve 49,76 gün, olarak belirlenmiştir. Bulguların C. carnea tarafından Panaphis juglandis ve Chromaphis juglandicola'nın biyo-kontrollerindeki olası etkileri tartışılmıştır. Elde edilen sonuçlar yaprakbitleri için hazırlanacak mücadele programlarında kullanılabilecektir.

Small walnut aphid (Chromaphis juglandicola (Kalt.) (Hem.: Aphididae) and Dusky-veined walnut aphid (Panaphis juglandis) (Goeze) (Hemiptera: Callaphididae) are important pests in walnut orchards in Lake Van Basin, Turkey. Aphids, which are colonized separately in the upper and lower parts of the walnut leaf, cause loss of quality and quantity in the walnut when their population is dense. In this study, population growth rate parameters based on feeding with both aphids of Chrysoperla carnea (Stephen) (Neuroptera: Chrysopidae), which is one of the important predators of the pest, were determined. The experiments were carried out in climatic rooms under 25±10°C, 65±5% humidity and 16: 8 (L: D) h (5,000 lux) lighting time conditions. Life table parameters were estimated according to age-stage, two-sex life table 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 0.082 d-1, 1.082 d-1, 59.47 offspring and 49.76 d, respectively of C. carnea fed on Chromaphis juglandicola and Panaphis juglandis. Results obtained might be used in pest management program that will be prepared for the aphids.

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.