Trichome-mediated defence in wild and cultivated tomato cultivars has been extensively studied against some mite species for several decades. Previous studies have shown that this mechanism negatively affects phytophagous mites and their predators. To better explain the tritrophic relationship of tomatoes, the interactions between population densities of the tomato rust mite, Aculops lycopersici (Massee) (Acari: Eriophyidae), and its predators on the tomato cultivars, namely, Dora, Etna, Grande, H2274, Jana and M1103, and the trichome densities of these cultivars were investigated in both a climatic room and an organic tomato field from 2014-2015. Under both controlled and field conditions, the A. lycopersici population density was significantly higher in the stake tomato cultivars, Jana and Etna, than in other tomato cultivars. When the tomato rust mite’s population density was the highest during mid-August and mid-September in the tomato field, the population density of the predator species, Tydeus kochi Oudemans (Tydeidae), showed a similar population pattern and significant positive correlation with the A. lycopersici density. However, density of this predator mite was significantly lower than that of A. lycopersici over the entire season. Remarkably, the glandular trichome type VI density was significantly higher in the stake cultivars than other cultivars. In contrast, significantly fewer glandular trichomes were found in the indeterminate tomato cultivars, Grande and H2274, which had fewer tomato rust mites and larger tydeid mite predator densities. These results support the hypothesis that trichomes provide excellent shelter for tomato rust mites and are obstacles for its predator mites. However, the population density of the insect predator, Macrolophus sp., was not affected by the trichome density or tomato cultivar, but its population density was not significantly correlated with that of the A. lycopersici population.

The life table parameters of Tetranychus urticae were evaluated on 7 eggplant cultivars namely, Anamur, Aydin Siyahi, Balikesir 76, Kemer, Pala 49, Topan 374, Yalova Topan, in controlled laboratory conditions in day ight for 16 hours 27 +/- 1 °C temperature, 65% relative humidity. Assays were conducted on eggplant leaflets in Petri dishes. There was a significant difference in the durations of egg and juvenile development of T. urticae. However the survival rates of T. urticae were not significantly different on the tested eggplant cultivars. The values of the natural rate of increase, rm, (0.218-0.269), net reproduction rate, R0, (26.74-45.51) and the mean generation time, T, (13.31-15.45) significantly differed among eggplant cultivars. Notably, the shortest development duration as indicated by the lowest rm and R0 values were observed on Pala 49 followed by Anamur and Balikesir 76 cultivars.

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SummaryPepper cultivar preferences of Tetranychus urticae Koch, 1836 (Acari: Tetranychidae) were determined by comparing its development, survival, oviposition, life table parameters and population development under controlled laboratory conditions with a 16L:8D photoperiod at 27±1ºC and 65±5% RH in Bursa (Turkey) during 2015-2016. Based on assays performed on leaf discs of six pepper cvs BT-Ince Sivri, BT-Burdem, BT-Burkalem, AHCRIÇarliston, AHCRI-Yağlık and AHCRI-Kandil Dolma, there were significant differences in egg hatch, juvenile development duration, intrinsic rate of natural increase (rm), net reproductive rate (Ro) and mean generation time (T) of the mite. The study showed that the life table parameters, rm (0.16-0.24), ) and T (14.22-16.39) for T. urticae were different when it was fed on different pepper cultivars. Significantly lower life table parameter values (rm, Ro and T) for T. urticae were observed on cv. BT-Ince Sivri, followed by cvs BT-Burdem and BT-Burkalem. Additionally, the mite densities on pepper seedlings of these three cultivars were significantly lower compared with those on seedlings of cvs AHCRI-Çarliston, AHCRI-Yağlık and AHCRI-Kandil Dolma. Furthermore, a lower survival rate was observed during juvenile development on cv. BT-Ince Sivri. Among the pepper cultivars, cv. BT-Ince Sivri had the lowest life table parameter values. Thus, the findings suggest that cvs AHCRI-Çarliston, AHCRI-Yağlık and AHCRI-Kandil Dolma are more susceptible to T. urticae than cvs Bursa BT-Ince Sivri, BT-Burdem and BT-Burkalem. Keywords:Pepper, cultivar, demographic parameters, two-spotted spider mite, population development ÖzetBu çalışmada Tetranychus urticae Koch, 1836 (Acari: Tetranychidae)'nin farklı biber çeşitleri arasındaki konukçu tercihi Bursa (Türkiye)'da 2015-2016 yılları arasında kontrollü laboratuvar koşullarında (16:8 aydınlık: karanlık, 27±1ºC sıcaklık, %65±5 orantılı nem) elde edilen zararlının gelişim, canlılık, ovipozisyon, hayat tablosu parametreleri ve popülasyon gelişim verileri karşılaştırılarak belirlenmiştir. Altı farklı biber çeşidi (BT-Ince Sivri, BT-Burdem, BTBurkalem, AHCRI-Çarliston, AHCRI-Yağlık ve AHCRI-Kandil Dolma) yapraklarıyla yapılan testler sonucunda akarın yumurta açılımı, ergin öncesi dönemlerinin gelişme süresi, kalıtsal üreme yeteneği (rm), net üreme gücü (Ro) ve toplam üreme oranı (GRR) açısından istatistikî anlamda önemli farklılıklar bulunmuştur. Bu çalışmada, T. urticae farklı biber çeşitleri üzerinde beslendiği zaman hayat tablosu parametre değerlerinin rm (0.16-0.24), ) değişiklik gösterdiği belirlenmiştir. Tetranychus urticae'de önemli düzeyde daha düşük biyodemografik parametre değerleri (rm, Ro ve T) sırasıyla BT-Ince Sivri, BT-Burdem ve BT-Burkalem çeşitlerinde saptanmıştır. Buna ek olarak, bu üç çeşidin biber fideleri üzerindeki popülasyon yoğunluğu da diğer üç çeşide (AHCRI-Çarliston, AHCRIYağlık ve AHCRI-Kandil Dolma) göre önemli düzeyde daha düşük bulunmuştur. Ayrıca, gelişme döneminde en düşük akar canlılığı BT-Ince Sivri çeşidinde gözlemlenmiştir. ...