نامه انجمن حشرهشناسی ایران (Feb 2013)
Resistance of different grape cultivars to grape erineum mite, Colomerus vitis (Acari: Eriophyidae), in the laboratory
Abstract
The grape erineum mite (GEM), Colomerus vitis Pagenstecher, is a serious pest of grape orchards in western Iran and sometimes causes a considerable damage to the crop. Initial observations in Hamedan region showed that the damage of the pest is not the same on different cultivars. Therefore, the resistance of different vine cultivars to GEM was studied to determine the potential use of resistant cultivars in the pest management programs. The resistance of ten vine cultivars including White Thompson seedless, Red Thompson seedless, Fakhri, Yaghuti, Asgari, Muscat Gordo, Khalili, Flame seedless, Gazne and Shahani were studied under laboratory conditions at a temperature of 25 ± 1°C, 65 ± 5% R.H. and a photoperiod of L16: D8 h using a pot disk method. Muscat Gordo, Gazne and White Thompson seedless cultivars showed the lowest feeding repellency to the GEM with 100.4 ± 0.45, 95.5 ± 0.77 and 87.4 ± 0.64 mites per leaf and the highest feeding repellency was observed in Shahani, Flame seedless and Yaghuti with 20 ± 1.23, 24.2 ± 1.24 and 24.7 ± 2.15 mites per leaf, respectively. The highest oviposition rate was observed in Muscat Gordo and Gazne with 148.31 ± 1.26 and 129.3 ± 2.26 eggs per leaves, respectively, and the lowest on Shahani with 10 ± 1.37 eggs per leaves. There was no significant difference between infested and non-infested leaf areas in Shahani. Moreover, Shahani and Yaghuti had the highest bristle-like trichome density, whereas, Muscat Gordo and Gazne had the highest hair-like trichome density. According to the obtained results, Shahani and Yaghuti had the highest, and Muscat Gordo and Gazne had the lowest resistance level to the GEM.