Susceptibility of Ceratitis capitata Field and Laboratory Strains to Malathion and Spinosad in Tunisia

Spinosad combined with entomopathogenic nematode for biocontrol of the Mediterranean fruit fly (Ceratitis capitata [Wiedemann]) on citrus

“…As the laboratory strain has been in culture quite longer than the field strain, it is conceivable that some of the higher mortality recorded in the laboratory strain is due to trait deterioration in the laboratory strain. This goes in parallel to spinosad LC 50 of C. capitata in Tunisia where 22 ppm and 127.95 ppm for laboratory and field population, respectively, were recorded (Guerfali et al 2020). Reasonably, the field strain may simply have innate fitness factors.…”

“…Data were analyzed using probit analysis models in the Stat program (Finney 1964;Brown et al 2001). Mortality rates were corrected by using the Abbott formula (Abbott, 1925).…”

“…Such plans should be fully exploited especially in the new citruscultivated areas as a recently published study (Dritsoulas et al 2021) confirmed that reclaimed desert habitats of Egyptian citrus favor entomopathogenic nematode and microarthropod abundance. On the contrary, an exclusive use of spinosad may possibly generate the insect resistance (Guerfali et al 2020). This might be indirectly shown herein by the higher resistance in field strain than laboratory strain as well.…”

“…This highly pathogenic species is maintained in the microbial control laboratory, Giza, Egypt. It was originally isolated from the Rio Grande Valley of Texas, USA, and possesses several promising features (Grewal et al 2005); its effective host range runs across multiple insect orders. It has ability to exploit aspects of both ambusher and cruiser means of finding hosts and tolerate soil temperatures at approx.…”