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.
