Picudo Del Agave

CHEMICAL ECOLOGY

Electroantennogram and Behavioral Responses of Anastrepha suspensa (Diptera: Tephritidae) to Putrescine and Ammonium Bicarbonate Lures
PAUL E. KENDRA,1 WAYNE S. MONTGOMERY, NANCY D. EPSKY,
AND

ROBERT R. HEATH

USDAÐARS, Subtropical Horticulture Research Station, 13601 Old Cutler Rd., Miami, FL 33158

Environ. Entomol. 38(4): 1259Ð1266 (2009)

ABSTRACT At present,the most effective synthetic lures for pest Anastrepha fruit ßies are multicomponent blends that include ammonia and the diamine synergist putrescine (1,4-diaminobutane). Both chemicals generally have been regarded as protein cues that result in female-biased attraction. Using electroantennography (EAG) and ßight tunnel bioassays, this study evaluated response of the Caribbean fruit ßy, Anastrephasuspensa (Loew) to vapors released from commercial lure formulations of ammonium bicarbonate and putrescine. Over a range of doses tested, EAG response to ammonium bicarbonate was equivalent for both sexes, but female response was signiÞcantly greater than male response to putrescine and to a 1:1 mixture of ammonium bicarbonate and putrescine. Amplitude of EAG response to the mixture wasapproximately equal to the summation of responses to the individual substrates. Using a Þxed dose of substrate, EAG measurements from females 1Ð14 d old indicated that antennal sensitivity to both lures varied according to physiological state of the ßy. Peak response to ammonium bicarbonate was recorded from immature females, peak response to putrescine from sexually mature females. In bioassays, morefemales were captured with ammonium bicarbonate plus putrescine than with ammonium bicarbonate alone. This difference was not observed in males, resulting in a higher female to male ratio in captures with ammonium bicarbonate plus putreseine (3:1) versus ammonium bicarbonate alone (1:1). Results suggest that separate olfactory receptors are involved in detection of the two semiochemicals, and that theputrescine component is primarily responsible for the female-biased attraction. KEY WORDS Caribbean fruit ßy, synthetic attractants, 1,4-diaminobutane, olfaction, semiochemicals

The New World genus Anastrepha includes a number of invasive fruit ßies that are serious pests of tropical and subtropical fruit crops (Aluja 1994). Of the 198 described species of Anastrepha (Norrbom 2000), only 1species of economic importance has become established in FloridaÑthe Caribbean fruit ßy, A. suspensa (Loew). Indigenous to the West Indies, A. suspensa is now common in south Florida, where it is a quarantine pest of citrus and a production pest of other fruits, most notably common guava (Psidium guajava L.) (Greany and Riherd 1993). Several other Anastrepha species pose a threat to Floridaagriculture because of close proximity of populations in Mexico and the Caribbean basin. In addition, the increasing volume of foreign produce shipments entering the stateÕs ports creates a potential pathway for pest entry and spread (Kendra et al. 2007 and references therein). The Mexican fruit ßy, A. ludens (Loew), represents a particular threat because it has been detected in Florida in reThis articlereports the results of research only. Mention of a proprietary product does not constitute an endorsement or recommendation by the USDA. 1 Corresponding author, e-mail: paul.kendra@ars.usda.gov.

cent years (Thomas 2004) and its preferred hosts include grapefruit (Citrus x paradisi Macfad), one of FloridaÕs major agricultural exports (Weems et al. 2004). Other species of concern include A. obliqua(Macquart), A. fraterculus (Wiedemann), A. striata (Schiner), and A. grandis (Macquart) (White and Elson-Harris 1992). Because of the economic impact of Anastrepha pests, much attention has been focused on development of trapping systems for monitoring their populations. Surveillance programs traditionally have used McPhail traps baited with liquid protein, speciÞcally hydrolyzed torula yeast...