Author
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McQuate, Grant |
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Submitted to: Hawaiian Entomological Society Proceedings
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 10/15/2010 Publication Date: 4/15/2011 Citation: Mcquate, G.T. 2011. Tephritid fruit fly Populations in a Dragonfruit Orchard in Hawaii: Border Plant Use and Infestation. Hawaiian Entomological Society Proceedings. 42:41-48. Interpretive Summary: Dragonfruit, Hylocereus undatus, is a fruit of the night-blooming cereus. It is reported to have first been introduced to Hawaii about 1830, but commercial production has only been attempted in recent years. As a new crop, production methods are still being developed. Among production issues are documentation of pest problems and development of pest management procedures. Dragonfruit originating in Vietnam has been found, through import inspection in Japan, to be infested by both oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, B. cucurbitae (Coquillett) (Diptera: Tephritidae). Because both of these fruit fly species are present in Hawaii, there is a need to better understand the risk of infestation and to develop approaches to minimize chances of infestation for dragonfruit production in Hawaii intended either for local sales or for export. A standard tephritid fruit fly population control technique is the application of protein bait sprays. Dragonfruit production, however, provides a challenge to the use of protein bait sprays as a control technique because dragonfruit plants lack leaves and bait sprays are typically applied to foliage of host plants. In support of the development of dragonfruit as a commercial crop in Hawaii, a dragonfruit orchard on the east side of the island of Hawaii was monitored over the 2007 - 2008 fruiting seasons in order to document the levels, and spatial distribution, of tephritid fruit fly field populations, the level of infestation and to develop approaches for suppression of infestation. Low population levels (< 0.25 flies/trap/day) of both tephritid fruit fly species were present both seasons, with population detection most successful in traps placed in roosting host plants along the orchard border rather than within the orchard. Random collections of mature dragonfruits made near the end of the production seasons documented infestation in both production years by both tephritid fruit fly species: 4.1% (2007) and 28.0% (2008) for oriental fruit fly and 6.1% (2007) and 8.0% (2008) for melon fly. Approach to tephritid fruit fly field suppression in this crop is discussed. Technical Abstract: Dragonfruit, Hylocereus undatus, has been grown commercially in Southeast Asia, Australia, South America, Israel and the United States. In Hawaii, commercial fruit production has recently begun, based on newly introduced varieties. Dragonfruit originating from Vietnam, but intercepted in Japan, has been found to be infestated by oriental fruit fly, Bactrocera dorsalis, and melon fly, B. cucurbitae. Because both of these tephritid fruit fly species are present in Hawaii, there is risk of infestation by these species in Hawaii and fruit export requires postharvest quarantine treatment for disinfestation. For dragonfruit production in Hawaii intended both for local sales and for export there is a need to better understand the risk of infestation and to develop approaches to minimize chances of infestation. In support of the development of dragonfruit as a commercial crop in Hawaii, a dragonfruit orchard on the east side of the island of Hawaii was monitored over the 2007 - 2008 fruiting seasons in order to document the levels, and spatial distribution, of tephritid fruit fly field populations, the level of infestation and to develop approaches for suppression of infestation. Low population levels (< 0.25 flies/trap/day) of both tephritid fruit fly species were present both seasons, with population detection most successful in traps placed in roosting host plants along the orchard border rather than within the orchard. Based on random fruit collections near the end of the production seasons, infestation rate in mature fruits increased from 4.1% and 6.1% (2007) to 28.0% and 8.0% (2008) for oriental fruit fly and melon fly, respectively. Approach to field suppression in this crop, which lacks host foliage, is discussed. |
