FIELD RESPONSE OF RHYNCHOPHORUS-CRUENTATUS (COLEOPTERA, CURCULIONIDAE) TO ITS AGGREGATION PHEROMONE AND FERMENTING PLANT VOLATILES

Semiochemicals from 2.5 kg of chopped stem tissue from cabbage palmett o, Sabal palmetto (Waiter), frozen or fresh stem tissue from sugarcane , Saccharum officinarum L., or syncarp tissue from pineapple, Anana co mosus (L.), were equally suitable for field attraction of Rhynchophoru s cruentatus (F.) when used with 0.4 mg/d of its aggregation pheromone , 5-methyl-4-octanol (cruentol). Twenty-eight different chemicals know n to be fermentation products from palm sap were screened with 0.4 mg/ d cruentol for field attraction of R. cruentatus adults. Good chemical ly-mediated field trapping of R. cruentatus was achieved with cruentol plus ethyl acetate (852 mg/d) and to a lesser degree with each of the following: (S)-(-)-ethyl lactate (release rate not determined; ND), e thyl isobutyrate (40 mg/d), ethyl butyrate (255 mg/d), or ethanol (51 mg/d). However, none of the test chemicals with cruentol were as effec tive as 1.5 kg of fermenting sugarcane or S. palmetto tissue plus crue ntol. Also, none of these chemicals were attractive by themselves at t he rates tested. A combination of individually released ethanol (48 mg /d), ethyl acetate (131 mg/d), ethyl butyrate (34 mg/d), ethyl isobuty rate (40 mg/d), and (S)-(-)-ethyl lactate (ND) with cruentol was as ef fective for the capture of R. cruentatus as cruentol plus any of the i ndividual components at the rates tested. Several trap designs were ev aluated for future research and implementation of semiochemically-medi ated monitoring and management of R. cruentatus.