The thrips-borne tomato spotted wilt tospovirus is a serious economic threat to Georgia's flue-cured tobacco crop. Two thrips vectors, Frankliniella fusca (Hinds) and F. occidentalis (Pergande), are commonly encountered on tobacco foliage and blooms, respectively. Yellow sticky traps were monitored after a 48-h field exposure from March through June in 2003–2005 to assess thrips movement and species composition in the tobacco farm scape. During March each year there were similar numbers of F. fusca and the flower thrips complex [F.occidentalis, F. tritici (Fitch) and F. bispinosa (Morgan), combined] captured on sticky cards. During April, May and June, the flower thrips complex steadily became more abundant comprising around 60, 70, and 95% of the trap capture, respectively. Thrips vector species were captured throughout the entire sampling period. In April and May, F. fusca captures on stick traps related to F. fusca population densities on tobacco foliage. Some sampling periods had differences in thrips captures relative to a north, south, east, or west orientation, with each direction having the highest thrips numbers at least once each season. However, the overall seasonal mean capture was higher on the eastward direction all 3 yrs and on the westward direction on 2 of the 3 yrs, compared to the southern and northern directions. In a time-of-day study, very few thrips were captured between 1830 h and 0,700 h the following morning. Thrips movement increased in midmorning and peaked during midafternoon. It appears that sticky cards can be used to monitor early colonization of thrips species in tobacco fields plus monitor thrips movement throughout the day, thus providing information on when potential vectors arrive and move within the field. Sticky trap monitoring provides an alternative to direct plant observation for predicting thrips abundance on tobacco foliage and the need for thrips controls.

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