STUDIES ON RESISTANCE OF CERTAIN FIELD STRAINS OF THE MEDITERRANEAN FRUIT FLY, CERATITIS CAPITATA (WIED.) (DIPTERA: TEPHRITIDAE) AGAINST SOME ENVIRONMENTALLY-SAFE BIOPESTICIDES AND CONTEMPORARY PESTICIDES

Abstract

Toxicity, levels of resistance, development of resistance and certain biochemical effects of certain pesticides on the Mediterranean fruit fly Ceratitis capitata were studied. 1. Toxicity of tested Pesticides 1.1. Spinosad (Conserve 0.024%CB) Females of C. capitata were slightly more tolerable to the used pesticide than males on LC50, LC90 and LC99values, where females showed differently levels of tolerance to Conserve 0.024%CB. The respective values were 5635.24, 15558.62, 35604.21 ppm (for males) and 6033.97, 20395.43, 55041.84 ppm (for females). The toxicity line of males was nearly steeper than that of females. 1.2. spintoram (Radiant 12%SC) Results indicated that males of the laboratory strain of the Mediterranean fruit fly were proportionally more susceptible than females. The values of LC50, LC90 and LC99 for males and females were 1285.43, 3096.39, 6339.96 and 1456.86, 3515.23, 7207.43 ppm, respectively. The slope values of Ld-p line were nearly the same (3.356 and 3.350). 1.3. Spinosad (Tracer 24% SC) Both males and females of C. capitata laboratory strain were differently affected by Tracer 24 % SC showing values of LC50, LC90 and LC99 of 315.19, 364.55; 1893.36, 2763.15, and 8164.99, 14402.71 ppm, respectively. The slope value of toxicity lines of males was slightly more steeper (1.64) than that recorded for females (1.45).