Effects of Chlorpyrifos, Imidacloprid and neem seed powder on emergence of adults of the invasive fruit fly Bactrocera invadens (Diptera:Tephritidae)

Abdelaziz E. Gesmallah, Nabil H.H. Bashir, Mohamed E. Elkashif, Yousif O.H. Assad


Bactrocera invadens (Drew, Tsuruta and White) (Diptera:Tephritidae) is an invasive fruit fly species of Asian origin which was detected in twenty African countries. Now, the species is well established in several parts of the Sudan. The effects of Chlorpyrifos, Imidacloprid and neem seed powder on emergence of B. invadens adults were determined under laboratory condition. Third instars larvae were exposed to treated and untreated (control) sand.  Chlorpyrfos were tested at 2, 4,8,12,16 and 32 ppm, Imidacloprid at 2, 4, 8,16 and 32 ppm and neem seed powder at 312.5  (0.031%), 625 (0.063%),1250 (0.125%), 2500 (0.25%) and 5000 ppm (0.5%). Twenty mature third instars larvae were placed in petri dish (15 cm in diameter) to allow them to pupate in the treated and untreated sand. They were supplied with small pieces of mango fruit pulp to feed on. The experiment was replicated three times. Number of emerged adults was recorded after ten days and the mortality rate (%) was calculated. Observations on the effect of the tested chemicals on the pupae formation were taken. Data were analyzed using probit analysis. The three tested chemicals were found to be effective in inhibiting the emergence of adults but with varying degrees. The inhibition always increased with increasing the concentration of the chemicals. Chlorpyrifos was the most effective among the tested chemicals, with an LC50 of 4.13 ppm compared to Imidacloprid and neem seed powder which had an LC50 of 10.14 ppm and 1299.63 ppm, respectively. Emergence of adults was completely inhibited at concentration of 32 ppm of Chlorpyrifos. Pupation was much affected by Chlorpyrifos and Imidacloprid compared to neem seed powder.

Full Text: PDF


  • There are currently no refbacks.