Influence of the colour and height of sticky traps in attraction of Thrips tabaci (Lindeman) (Thysanoptera, Thripidae) and predatory thrips of family Aeolothripidae on garlic, onion and tomato crops

Abstract

Onion is one of the major crops cultivated in Azarbaijan (Noth-West Iran). Among various pests that affect the onion, Thrips tabaci (Lindeman) is considered as the most important pest. Numerous sprayings on this pest result in several economic and health problems for both producers and consumers. In the present study, the effect of colour and height of sticky traps were evaluated in attraction of adults and larvae of onion thrips and predatory thrips during the growing season in 2012 in Mamaghan region (North-West of Iran). Three replicates of yellow, white and blue sticky traps were mounted in four different heights (30, 50, 70 and 100 cm) on the fields of onion, garlic and tomato. The sticky sheets were examined every week, replaced and transferred to the laboratory for more investigation and counting, segregation and identification of the captured insects. Data were analysed using SAS software (Proc GLM, SAS Institute Inc., 2002). Attraction of adult onion thrips showed significant differences on different crops (F = 101.71, p < 0.0001), at different heights (F = 11.99, p < 0.0001) and for different trap colours (F = 42.39, p < 0.0001), as well as for traps colour and crop interaction (F = 8.59, p = <0.0001). Similar were results obtained for both the onion thrips larvae and the predatory thrips with different F values. Results indicated that yellow sticky traps were the appropriate one for thrips monitoring, which was installed at 70 cm in height above the ground.