Chemical studies on proteinaceous attractants for fruit flies, including the identification of volatile constituents

Abstract

The chemical characteristics of protein attractants for the Queensland fruit fly, Dacus tvyoni, have been investigated.Highly effective commercial fruit fly attractants were found to contain a large proportion of high molecular weight material. Lists are provided of the amino acids present in free and bound form in these hydrolysates. The products found by gas liquid chromatography-mass spectrometry analysis of methylene chloride extracts and head-space volatiles were mainly the primary and secondary products of amino acid degradation, including a number of aldehydes and significant amounts of ethylene. None of these aldehydes nor any of a number of others that may have been present in smaller quantities was found to be active when tested individually for attractancy. Nor did ethylene show any evidence of attractancy under the conditions of these tests. Strecker reagents (such as isatin), which stimulate the formation of amino acid degradation products, caused a temporary and relatively small elevation in attractancy of the commercial hydrolysates.Three enzymatic hydrolysates of a relatively pure protein (bovine serum albumin) were prepared and studied; one, a tryptic digest, was exceptionally attractive to the fruit fly. Analysis of methylene chloride extracts and head-space of these 'model' preparations revealed a number of significant differences between them, but the most important difference in relation to attractancy was found to be the presence of ammonium salts in the trypsin hydrolysate.Subsequent experiments showed that high attractancies could be attained by combinations of amino acid mixtures and ammonium bicarbonate, even though neither had high attractancy (under the particular conditions of these experiments) when tested independently. This apparent synergism was probably due to the attractancy of the ammonia coupled with a feeding stimulus provided by the amino acids.

Differences in Antennal Sensillae of Male and Female Peach Fruit Flies in Relation to Hosts

“…In addition, in B. oleae , sensilla on the third antennal segment respond to sex pheromones and other volatiles. Therefore, aristae and antennae of B. zonata were most likely sound receptors as well as the major sensory input conveying olfactory information about plant volatiles and pheromones ( Morton and Bateman 1981 , Robacker and Hart 1987 , Ehmer and Gronenberg 1997 , Renthal 2003 , El-Akhdar and Afia 2009 ).…”

Attractiveness of some food baits to the melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae)

“…Fermenting baits that release CO 2 and gases contain acids and alcohols that are attractive to flies (Gow, 1954;Morton and Bateman, 1981). Bactrocera cucurbitae responded significantly to the bait admixtures containing beer or vinegar.…”

Visual and odor stimuli influencing effectiveness of sticky spheres for trapping apple maggot flies Rhagoletis pomonella (Walsh) (Dipt., Tephritidae)

“…But each is associated with a different type of response. Ammonia emanates from proteinaceous tephritid fly food (BATEMAN and MORTON 1981;MORTON and BATEMAN 1981;HEN-DRICHS et al 1990). Butyl hexanoate is emitted by host fruit in a condition favorable to R. pornonella mating and oviposition (CARLE et al 1987).…”