The relation among the application of thiamethoxam for thrips control and the severity of peanut scab was evaluated in field experiments runned at Campinas and Pindorama, during 2001/2002, in split-plot design. Main plots consisted of the control and no control of thrips with thiamethoxam and, subplots, of six peanut cultivars: IAC-Tatu-ST, IAC-5, IAC-22 (upright type, short cycle), Runner IAC-886, Tegua and IAC-Caiapo (runner type, long cycle). The evaluations of number of thrips per leaflet and ratingof symptoms, were performed at 56 and 57 days after sowing date in Campinas and Pindorama, when the highest insect populations where registered. In both experiments a partial control of peanut scab was observed, and so, its severity was evaluated at 79 and 91 days of the plantation, in Campinas and Pindorama, respectively, using a rating scale based on symptons shown in stems and petioles. The results showed the efficiency of thiamethoxam in controling thrips in all cultivars. In both localities was observed a reduction in the severity of peanut scab, when thiamethoxam was applied. The severity of scab was higher in the upright cultivars, with the IAC-Caiapo showing the lower scores of severity. The yield was higher for the parcels treated with the insecticide, in both localities, and IAC-Caiapo presented superior yields in relation to the other cultivars. The action of thiamethoxam controling thrips and reducing scab severity should be more explored in integrated control practices.
Sphaceloma archidis; Enneothrips flavens; insecticide
