The influence of weedy field strips on the abundance patterns of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and predatory bugs of Orius spp. (Hemiptera: Anthocoridae), on faba bean and on weeds was investigated in Adana province, Turkey, during 2005-2006. There were two treatments: in one treatment, weeds at the margins and inside the plots were regularly controlled by tillage; in the other treatment no weed control was done. Thrips and Orius were sampled by beating faba bean plants and weeds. Orius niger (Wolff) was the most abundant predatory insect species in faba bean and flowering weeds, with numbers of adults and nymphs significantly greater in plots with weedy margins than in weed-free plots. Flowering weeds did not contribute to the abundance of F. occidentalis on faba bean. Abundance of adults of Orius spp. did not coincide with the abundance of F. occidentalis on faba bean or weeds. There were significant negative associations for numbers of Orius spp. among faba bean and the weed species Lamium amplexicaule L. or Sinapis arvensis L. (P<0.05), indicating movement of Orius individuals from the weeds to faba bean during March-April. Finally, faba bean and weeds may provide some benefits to predators, such as nectar, pollen, shelter and egglaying sites rather than as sources of insect prey. Cultivation of faba bean could be useful for conservation and augmentation of beneficial insects, including Orius spp. Furthermore, field margins bearing flowering weeds such as S. arvensis and L amplexicaule should be protected against destructive management practices, because they host considerable numbers of the Orius species.

The species composition of thrips and abundance of three pestiferous thrips species, Frankliniella occidentalis (Pergande), Thrips tabaci Lindeman and Frankliniella intonsa (Trybom) (Thysan., Thripidae) on weed species during winter and spring time were studied in vegetable production and polycultured areas in the eastern Mediterranean region of Turkey in years 2002 and 2003. Of a total of 61 543 thrips extracted from 8933 samples collected, 77% were adults. F. occidentalis was collected from all of 49 weed species sampled and F. intonsa was detected on 18 plant species between May and June. T. tabaci was collected from 42 of a total of 49 weed species. Immature thrips were extracted from 42 of a total of 49 weed species. Four weed species of a total 35 weed species sampled between April and May in the sampling areas hosted 63% of larvae and approximately 50% of F. occidentalis collected. A total of 23 thrips species was recorded from weeds sampled in this study. F. occidentalis accounted for 83% of a total 47 640 adult thrips collected and followed by low rates of T. tabaci and F. intonsa (9 and 1%, respectively). Melanthrips spp. accounted for 3.54% of total numbers of adult thrips. Flower-inhabiting thrips species and T. tabaci were most abundant on weeds between April and May when the number of weed species in bloom was greatest, then decreased to low levels after May. Most pestiferous thrips on weeds species were collected from vegetable production areas. F. occidentalis was the predominant thrips comprising over 80% in most months in the vegetable grown area. In polycultured area, the composition of adult thrips shifted monthly. While Melanthrips was the more prevailing thrips by rates 53% in February and 81% in March, F. occidentalis was the predominant thrips with 60 to 62% in spring, respectively.

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Cotton aphid, Aphis gossypii Glover, 1877 (Hemiptera: Aphididae), is a major pest in cotton fields. Neonicotinoids are important and highly prevalent insecticides currently used against A. gossypii and other herbivorous insect pests in the Mediterranean Region of Turkey. However, some insecticide applications against A. gossypii in the Çukurova Region have failed despite using high rates. Therefore, bioassays and enzyme analyses were conducted to determine resistance to imidacloprid and thiamethoxam in A. gossypii populations collected in 2015-2016 from cotton fields in this region. Resistance factors (RF) were 54.6 to 206.5 fold for imidacloprid and 5.7 to 65.7 fold for thiamethoxam. Populations from Kürkçüler (RF 206.5) had the highest LD50 for imidacloprid and from Körkuyu (RF 65.7) for thiamethoxam. Enzyme analysis revealed statistically higher metabolic resistance. Maximum enzyme activities were 17.8, 142.3 and 3.8 nM/min/mg protein for carboxylesterase for in Körkuyu, for glutathione S-transferase in Bahçe and for cytochrome P450 monooxygenase in Körkuyu, respectively. This study revealed the development of resistance in A.gossypii to neonicotinoid insecticides in Turkey and the need for new management strategies to break this resistance.