New Attractants for Males of the Solanaceous Fruit Fly Bactrocera latifrons

Abstract

alpha-Ionone, alpha-ionol, and their mixtures with phenolic volatiles act as potential male lures for the solanaceous fruit fly Bactrocera latifrons (Hendel). However, the attractiveness of these compounds is not as strong as that of other well-known tephritid male lures, such as methyl eugenol for Bactrocera dorsalis. Isophorone and isophorol, which have a partial skeletal structure of alpha-ionone/alpha-ionol (i.e., trimethylcyclohexene), were attractive to B. latifrons males, and their mixtures with alpha-ionol exhibited stronger activity than any of the individual compounds. We also tested 3-oxo-alpha-ionone, 3-oxo-alpha-ionol, 3-hydroxy-alpha-ionone, and 3-hydroxy-alpha-ionol, hybrid compounds between isophorone/isophorol and alpha-ionone/alpha-ionol. 3-Oxo-alpha-ionone and 3-oxo-alpha-ionol were active both as attractants and phagostimulants for males. The results suggest that the introduction of an oxygen atom at the 3-position of the alpha-ionone/alpha-ionol molecule optimizes the specific chemosensory responses in B. latifrons males.

3-Oxygenated α-ionone derivatives as potent male attractants for the solanaceous fruit fly, Bactrocera latifrons (Diptera: Tephritidae), and sequestered metabolites in the rectal gland

“…The attractant and feeding stimulant activities were examined by the method reported previously (Ishida et al, 2008). Sexually mature adults (50 males and 50 females) were introduced into a screen cage (30ϫ30ϫ45 cm).…”

“…6 times). In order to pre-examine the responsiveness of males, a brief bioassay was conducted for the known attractant, 3-oxo-a-ionone (3) under the same conditions employed for Ishida et al (2008). Although qualitative, the sensitivity of males was the same as that observed for compound 3 in the previous paper (dose: 100 mg/filter paper, see Table 1).…”

“…A 1-ml portion of each rectal gland sample obtained above was subjected to GC quantification, using 1-pentadecanol as an internal standard. Table 1 shows mean total numbers of males and females of B. latifrons attracted and feeding on aionone/a-ionol analogs 5, 6, 8 and 9, comparing those with preceding bioassay data for 1, 2, 3, 4 and 7 (Ishida et al, 2008). 3-Oxo-7,8-dihydro-aionone (5) and 3-oxo-7,8-dihydro-a-ionol (6) elicited levels of both attraction and feeding similar to those noted for the corresponding 7,8-unsaturated derivatives (3 and 4) in males.…”

“…We recently found a series of 3-oxygenated a-ionone/ionol analogs [e.g. 3-oxo-a-ionone (3) and 3-oxo-aionol (4)] to be attractants as well as feeding stimulants for the males of B. latifrons (Ishida et al, 2008) (Fig. 1).…”

“…In order to further improve the attractant potency of the lure chemicals, we have examined several analogs by modifying the 3-oxygenated a-ionone/a-ionol structures. We report here the attractiveness and 3-Oxygenated a a-ionone derivatives as potent male attractants for the solanaceous fruit fly, Bactrocera latifrons (Diptera: Tephritidae), and sequestered metabolites in the rectal gland Hiroshi ENOMOTO, 1 Tatsuaki ISHIDA, 2, † Akito HAMAGAMI 2 and Ritsuo NISHIDA feeding stimulant activity of several synthetic 3-oxygenated C 13 -norterpenoid analogs to compare the activity with a series of related compounds previously reported by Ishida et al (2008). After feeding on an attractant source, males of Bactrocera species incorporate the chemicals selectively in their rectal glands, which are presumed to function as a reservoir of sex pheromone to attract females, as demonstrated in methyl eugenol-B.…”