Abstract:
The experiments of the present study were conducted under laboratory conditions at temperature 27 ± 2 ºC, relative humidity (RH) 30 ± 5% and the photoperiod of L12:D12 at the Plant Protection Department, College of Agricultural Studies “Shambat”, Sudan University of Science and Technology (SUST), to study the lethal effect of Neem (Azadirachta indica A.juss) and Jatropha (Jatropha curcas L.) seeds ethanol extracts on the adults of the Asian fruit fly (Bactrocera invadens Drew Tsuruta and White) (Diptera:Tephritidae).
In this study different concentrations of the Jatropha and Neem seeds ethanol extracts were used (2.5%, 5%, and 7.5%) on the Asian fruit flies by using topical application, contact and feeding methods and the results were taken after 24, 48 and 72 hours. The obtained results clarifies that the highest concentration 7.5% of Jatropha seeds ethanol extract showed a high mortality percentage (7.25) than the highest concentration of Neem seeds ethanol extract by using topical and contact methods after 72hours of exposure. The highest concentration of Neem seeds ethanol extract gave high mortality rate (4.5) than the jatropha seeds ethanol extract by using feeding method after 72 hours of exposure.
The results of the host preference showed that B. invadens prefers Guava fruit. This was found by counting the survived larvae found per infected fruit after 10 days. The results showed that the B. invadens prefers Guava (19.33) followed by Mango (8.66) then Grapefruit (1) and finally Banana (0.66). No infestations were found in Orange, Pepper, and Apple.
Also the results of the color preference showed that B. invadens prefers yellow color. This was obtained by counting the survived larvae found per infected fruit after 10 days. The results demonstrated that the B. invadens prefers yellow Guava (40) than green Guava (28) and the yellow Mango (18) was more preferred than green Mango (9). However, this means that the yellow color was more preferred than the green color which indicates the physiological maturity of the fruit. However, this experiment also proved that green Guava was preferred to yellow mango.
