The aphids, aphid parasitoids, and hyperparasitoids found in citrus orchards, the parasitoids’ and hyperparasitoids’ seasonal abundance, and the plant–aphid–parasitoid relationships in Hatay, Osmaniye, Adana, and Mersin provinces of the east Mediterranean region of Turkey are presented in the present 2-yr study. Aphidius colemani Viereck, Binodoxys angelicae (Haliday), and Lysiphlebus confusus Tremblay and Eady (Hymenoptera: Braconidae: Aphidiinae) were encountered as the most common parasitoids among 10 identified aphidiine and aphelinid taxa on different citrus species. Hyperparasitoids belonging to the genera Alloxysta , Phaenoglyphis , Asaphes , Pachyneuron , Syrphophagus , and Dendrocerus are reported for the first time emerging from aphids feeding on citrus in Turkey. Among them, Asaphes spp., Pachyneuron spp., and Syrphophagus spp. were recorded as the most common ones. Citrus reticulata Blanco and Citrus limon (L.) Burm. fil. were recorded as main hosts for the aphid parasitoids and their hyperparasitoids.

Planococcus citri Risso, 1813 (Hemiptera: Pseudococcidae), is one of the major pest of citrus and many other orchards crops, and ornamental plants in subtropical and tropical regions of the world. The influence of temperature on P. citri development and fecundity has a critical role in integrated pest management strategies to reduce the population to below the economic threshold by biological or chemical control methods. The study investigated some bioecological characteristics, such as, development time, duration of biological stages, sex ratio, daily and total fecundity per female, and longevity of P. citri, under different temperature regimes during 2015-2016 in Citrus Pest Laboratory at Çukurova University. The shortest egg stage development for females and males were determined as 2.7 and 2.7 d with alternating temperatures of 25/30°C (12:12 h), respectively. The first nymph stage lasted 7.86 d for females, and 8.1 d for males at 25°C. The longest duration for the second nymph stage was obtained at 15°C with 25.7 and 22.5 d for females and males, respectively. The third nymph stage for P. citri females completed in 7.0 d at 25°C, and the pupal stage for P. citri males lasted 7.8 d at 25°C. The development thresholds of females and males were calculated as 8.5 and 9.5°C, respectively. Also, thermal constants of females and males were 666.67 and 500.00 degree-days. The optimum development temperature was determined as 25/30°C.

Population fluctations of Citrus mealybug [Planococcus citri (Risso)

Colak Ates et al.: The identification of the resistance levels of Fusarium oxysporum f. sp. radicis-lycopersici and Tomato yellow leaf curl viruses in different tomato genotypes through traditional and molecular methods -2203 -

The western flower thrips, Frankliniella occidentalis (Pergande), is one of the most important insect pests in the Mediterranean region of Turkey. Thrips infestation is the main cause of vegetable crops losses in low polythene tunnels and plastic greenhouses. Chemical control has been the primary means to control F. occidentalis in protected cultivation systems in Turkey. A search of alternatives to conventional insecticides for the control of F. occidentalis has drawn increased interest in the use of biocontrol agents. This study evaluated the control efficiency of F. occidentalis on eggplants through releases of the predatory mite Amblyseius swirskii (Athias-Henriot) at a rate of 50 adults per m 2 in plastic greenhouses or low polythene tunnels. Samplings of F. occidentalis from flowering to harvesting of the eggplants revealed that neither preventative nor curative releases of the predatory mite reduced the thrips population densities below a mean of 3 thrips per flower (i.e. control threshold). We discuss various factors that may have affected the efficiency of the predatory mite on eggplants or the failure of the biological control.