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ARS Home » Pacific West Area » Hilo, Hawaii » Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center » Tropical Crop and Commodity Protection Research » Research » Publications at this Location » Publication #201680
Title: Use of Alpha-Ionol + Cade Oil for Detection and Monitoring of Bactrocera latifrons (Diptera: Tephritidae) Populations

Author
item McQuate, Grant
item BOKONON-GANTA, AIME - PEPS, UNIV OF HAWAII MANO
item Jang, Eric

Submitted to: Fruit Flies of Economic Importance International Symposium
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/22/2008
Publication Date: 12/31/2008
Citation: Mcquate, G.T., Bokonon-Ganta, A.H., Jang, E.B. 2008. Use of Alpha-Ionol + Cade Oil for Detection and Monitoring of Bactrocera latifrons (Diptera: Tephritidae) Populations. Fruit Flies of Economic Importance, 10-15 September, 2006, Salvador, Brazil. Socidade Brasileira para o Progresso da Ciencia. 355 pp

Interpretive Summary: Because of their potential for economic damage to fruit and vegetable crops, it is important to be able to detect and monitor tephritid fruit fly populations. Lures that are attractive to males have been identified for many fruit fly species and have been valued for use in detection, monitoring and suppression of tephritid fruit fly populations. For Bactrocera latifrons (Hendel), alpha-ionol, with the addition of cade oil, is the established male lure. Further research, though, has been needed to better understand the efficacy of alpha-ionol + cade oil for detection and monitoring of B. latifrons populations. We conducted experiments to determine (1) The age of lure response of males; (2) The field performance of treated wicks; and (3) The effectiveness of alpha-ionol + cade oil in detecting B. latifrons populations at sites where B. latifrons was recovered in fruit collections. Through wind tunnel studies using adult flies recovered from field - collected turkeyberry (Solanum torvum L.) fruits, we documented that B. latifrons male response gradually increased with age, from 5% at age 2 to 45% at age 28. Male response exceeded 50% of the peak response by day 7, and exceeded 75% and 90% by days 14 and 21, respectively. This data indicates what portion of the field population is being assessed through trap captures. These results suggest that the response of B. latifrons to alpha-ionol + cade oil develops at a younger age than does the comparable response of B. dorsalis to methyl eugenol and B. cucurbitae to cuelure. Through tests with sterile, laboratory-reared flies, released in an orchard with Jackson traps baited with 2.0 ml alpha-ionol and 1.0 ml cade oil, aged for 0, 2, 4, 6, 8, 10, 12, and 14 weeks, we found that trap catch declined steadily over the 14 weeks of aging, declining to 50% of the fresh wick catch after 6½ weeks. This data helps to identify the timing for replacing/recharging the lure to ensure that the male lure maintains a satisfactory level of attractiveness. Standardly, attractants are replaced when their catch drops below 50% of their catch when fresh. Finally, using Jackson traps baited with alpha-ionol + cade oil and set out in 13 sites with well developed turkeyberry patches in the vicinity of Haiku, Maui, and serviced every two weeks over the course of 1½ years, we found that 75.5% of the times B. latifrons was recovered from fruits collected in a given patch, B. latifrons was also detected through trap catches in that patch. Trap detection improved to 85.3%, 90.0% and 92.6% by including the results of subsequent trap servicings up to 2 weeks, 4 weeks, and 6 weeks later, respectively. One would expect B. latifrons males, developing from eggs or larvae in fruits at the time of fruit collection, to be old enough to respond to alpha-ionol + cade oil within 6 weeks of fruit collection. These results show that alpha-ionol + cade oil is an effective tool for detection of B. latifrons populations.

Technical Abstract: Alpha-ionol, with the addition of cade oil, is the established male lure for Bactrocera latifrons (Hendel). Cade oil contains over 200 different compounds, a number of which (= active ingredients) help to synergize the attractiveness of alpha-ionol to male B. latifrons. In order to better understand the efficacy of alpha-ionol + cade oil for detection and monitoring of B. latifrons populations, we determined (1) The age of lure response of males; (2) The field performance of treated wicks; and (3) Its effectiveness in detecting B. latifrons populations at sites where B. latifrons was recovered in fruit collections. (1) Age of Response. Wild flies were used in wind tunnel bioassays to assess the age of response of adult male B. latifrons to alpha-ionol + cade oil. B. latifrons male response gradually increased with age, from 5% at age 2 to 45% at age 28. Male response exceeded 50% of the peak response by day 7, and exceeded 75% and 90% by days 14 and 21, respectively. These results suggest that the response of B. latifrons to alpha-ionol + cade oil develops at a younger age than does the comparable response of B. dorsalis to methyl eugenol and B. cucurbitae to cuelure. (2) Wick Performance. Laboratory-reared flies were used to assess the field performance of wicks treated with 2.0 ml alpha-ionol and 1.0 ml cade oil. Treated wicks were aged in Jackson traps in a nonhost orchard in Hilo, Hawaii, for 0, 2, 4, 6, 8, 10, 12, and 14 weeks and then set out in a randomized complete block design. Sexually mature adults were released, with traps recovered after 24 hours. Trap catch declined steadily over the 14 weeks of aging, declining to 50% of the fresh wick catch after 6½ weeks. (3) Effectiveness in Detecting B. latifrons Populations. Every two weeks, over the course of 1½ years, Jackson traps baited with alpha-ionol + cade oil were serviced at 13 sites with well developed turkeyberry (Solanum torvum L.) patches in the vicinity of Haiku, Maui. Concurrent to trap servicing, fruits were collected, as available, from each patch for the assessment of the level of infestation. 75.5% of the times B. latifrons was recovered from fruits collected in a given patch, B. latifrons was also detected through trap catches in that patch. Trap detection improved to 85.3%, 90.0% and 92.6% by including the results of subsequent trap servicings up to 2 weeks, 4 weeks, and 6 weeks later, respectively. One would expect response of adults, developing from eggs or larvae in fruits at the time of fruit collection, within 6 weeks of fruit collection. Lack of detection may have occurred where flies emerging from fruits died before becoming responsive to the bait or where the fly population occupied only a small portion of a large patch, with the population distant from the trap.