Laboratory Evaluation of Natural and Synthetic Aromatic Compounds as Potential Attractants for Male Mediterranean fruit Fly, Ceratitis capitata

Abstract

Ceratitis capitata, the Mediterranean fruit fly, is one of the most serious agricultural pests worldwide responsible for significant reduction in fruit and vegetable yields. Eradication is expensive and often not feasible. Current control methods include the application of conventional insecticides, leading to pesticide resistance and unwanted environmental effects. The aim of this study was to identify potential new attractants for incorporation into more environmentally sound management programs for C. capitata. In initial binary choice bioassays against control, a series of naturally occurring plant and fungal aromatic compounds and their related analogs were screened, identifying phenyllactic acid (7), estragole (24), o-eugenol (21), and 2-allylphenol (23) as promising attractants for male C. capitata. Subsequent binary choice tests evaluated five semisynthetic derivatives prepared from 2-allylphenol, but none of these were as attractive as 2-allylphenol. In binary choice bioassays with the four most attractive compounds, males were more attracted to o-eugenol (21) than to estragole (24), 2-allylphenol (23), or phenyllactic acid (7). In addition, electroantennography (EAG) was used to quantify antennal olfactory responses to the individual compounds (1–29), and the strongest EAG responses were elicited by 1-allyl-4-(trifluoromethyl)benzene (11), estragole (24), 4-allyltoluene (14), trans-anethole (9), o-eugenol (21), and 2-allylphenol (23). The compounds evaluated in the current investigation provide insight into chemical structure–function relationships and help direct future efforts in the development of improved attractants for the detection and control of invasive C. capitata.

TLC-Based Bioassay to Isolate Kairomones from Tea Tree Essential Oil That Attract Male Mediterranean Fruit Flies, Ceratitis capitata (Wiedemann)

“…Irradiated pupae were shipped initially to the USDA-APHIS Medfly Project (Sarasota, FL, USA) and then to the USDA-ARS SHRS (Miami, FL, USA). Rearing methods were similar to those described in literature [24,38,43]. Flies used for all studies were 5 to 10 days old, sexually mature virgin males.…”

“…EAG test substrates (odorant sources) consisted of neat tea tree oil (TTO), the five fractions of TTO obtained by semipreparative TLC, and 2-butanone (99% pure; Sigma-Aldrich, St. Louis, MO, USA) as a standard reference compound (positive control) for EAG with Diptera [35,43,[48][49][50][51]. Each substrate (20 mg) was placed into a separate 250 mL hermetic glass bottle fitted with a septum port lid (Swagelok, Solon, OH, USA) and equilibrated overnight at 24 • C to allow for headspace saturation with volatiles.…”

Activity of Some Plant and Fungal Metabolites towards Aedes albopictus (Diptera, Culicidae)

“…Following these results, cyclopaldic acid could provide different management opportunities in different mosquito species control. Some other, mainly natural, phenols were evaluated as potential attractants of Ceratitis capitata (Wiedemann) male, the Mediterranean fruit fly [ 59 ]. Recently, α-costic acid, a well-known sesquiterpenoid isolated from the native Mediterranean plant Dittrichia viscosa (L.) Greuter, had showed a significant acaricidal activity against Varroa destructor Anderson and Trueman, the parasite mite of Apis mellifera L., the Western or European honeybee [ 60 ].…”

Activity of Some Plant and Fungal Metabolites Towards Aedes Albopictus (Diptera, Culicidae)

“…Following these results, cyclopaldic acid could provide different management opportunities in different mosquito species control. Some other, mainly natural phenols, were evaluated as potential attractants of Ceratitis capitata (Wiedemann) male, the Mediterranean fruit y [81]. Recently, a-costic acid, a well-known sesquiterpenoid isolated from the native Mediterranean plant Dittrichia viscosa (L.) Greuter, had showed a signi cant acaricidal activity against Varroa destructor Anderson and Trueman, the parasite mite of Apis mellifera L., the Western or European honey bee [82], and costic acid isomers contained in n-hexane extracts of the same plant have been held accountable for the contact toxicity against the granary weevil adults Sitophilus granarius (L.) [83].…”