COLOR ATTRACTION OF YELLOW TEA THRIPS (SC IRTOTHRIPS DORSALIS HOOD)

Trapping tests for yellow tea thrips, Scirtothrips dorsalis, were carr ied our using 15 colored sticky boards in a mandarin orange (Citrus un shiu MARC.) orchard in Schizuoka Prefecture, Japan in 1994. The spectr al reflectance (SR) from 400 to 700 nm of the colored boards covered w ith transparent sticky sheeting was measured to determine the relation ship between spectral reflectance curves and trap catches. More adult thrips were collected on yellowish-green, green, and yellow boards. Ye llowish green tended to trap most adult thrips. The low SR from 400 to 450 nm, increasing SR from 480 to 540 nm, and high SR from 540 to 580 nm is believed to be involved in the attraction. Similar spectral cha racteristics are observed in leaves and young fruits of mandarin orang es. The color of younger leaves is believed to be more attractive than young fruits and old leaves because of their comparatively high SR.