YELLOW TRAPS AND INSECTICIDES FOR CONTROL OF A STRAIN OF SWEET-POTATOWHITEFLY AND ASSOCIATED VIRUS INCIDENCE ON PEPPER

Bemisia tabaci (Gennadius) is the most important vector of viruses whi ch cause diseases of ''serrano'' pepper in southern Tamaulipas, Mexico . This insect is highly attracted to yellow surfaces. When 1,240 yello w traps/ha were uniformly placed in plots, plants with virus symptoms were reduced 61%, 59%, and 15% in 1987/1988, 1988/1989, and 1990/1991, respectively, on the last sampling date yet there was no significant difference in treated and untreated plots. In plots without treatment 78, 91, and 100% of plants exhibit virus symptoms on the last sampling date in the same years, respectively. Plots with traps increased yiel ds of peppers 539%, 202%, and 341% in 1987/1988, 1988/1989, and 1990/1 991, respectively, compared to the check. Traps + permethrin at 110 g (AI)/ha reduced populations of B. tabaci adults 78% in the 1987/1988. Permethrin-treated plots without traps increased yields 312% and 366% compared to the control in 1988/1989 and 1990/1991 seasons, respective ly. During these same years yield increases were greater than the untr eated check when Lambda cyhalothrin, cypermethrin, phosphamidon, dimet hoate, naled, Safer(TM) soap, amitraz, and endosulfan were applied in the same tests.