Nonhost Status of Commercial Persea americana ‘Hass’ to Anastrepha ludens, Anastrepha obliqua, Anastrepha serpentina, and Anastrepha striata (Diptera: Tephritidae) in Mexico

Abstract

The objective of this study was to determine the host status in Mexico of commercially cultivated and marketed avocado, Persea americana (Mill.), 'Hass' to Anastrepha ludens (Loew), Anastrepha obliqua (Macquart), Anastrepha serpentina (Wiedemann), and Anastrepha striata (Schiner) (Diptera: Tephritidae). Experiments in Michoacán, Mexico, were carried out in six orchards located at three altitudes above sea level during two times (August-October 2001 and April-June 2002). They included choice ('Hass' avocado plus natural host) and no-choice foraging behavior tests on trees under field cages; no-choice, forced infestation trials on caged, fruit-bearing branches in the field, and with individual fruit under laboratory conditions; infestation trials using 'Hass' avocados left unprotected over 1 and 7 d on the ground of orchards; studies to ascertain depth of oviposition and determine egg hatchability; and experiments to determine susceptibility by using time elapsed since removal of fruit from tree as the experimental variable. We trapped adult Anastrepha (n = 7,936) in all orchards and dissected fruit (n = 7,695) from orchards and packing houses (n = 1,620) in search of eggs or larvae. Most (96.7%) A. ludens, A. obliqua, A. striata, and A. serpentina adults were captured in low-elevation orchards. No eggs or larvae were detected in any of the fruit from foraging behavior studies or dissected fruit from orchards or packing houses. Of 5,200 mature, intact fruit on trees in the field forcibly exposed to no-choice female oviposition activity (five females/fruit), we only found four fruit infested by A. ludens but no adults emerged. 'Hass' avocados only became marginally susceptible to attack by A. ludens (but not A. obliqua, A. serpentina, and A. striata) 24 h after being removed from the tree. Fruit placed on the ground in orchards (n = 3,600) were occasionally infested by Neosilba batesi (Curran) (Diptera: Lonchaeidae), a decomposer, but not Anastrepha spp. Based on our results, commercially cultivated and marketed P. americana 'Hass' should not be considered a natural host of A. ludens, A. obliqua, A. striata, and A. serpentina in Mexico.

Host Status of Avocado (‘Hass’) to <I>Ceratitis capitata</I>, <I>Ceratitis rosa</I>, and <I>Ceratitis cosyra</I> (Diptera: Tephritidae) in South Africa

“…There are isolated instances where C. capitata and C. rosa larvae can occur in overripe rotting avocados (Grove 2001a), but under normal South African orchard conditions no fruit ßy larval development takes place in avocado fruit (Schwartz 1978;Du Toit and TufÞn 1980;De Villiers and van den Berg 1987;Du Toit and De Villiers 1990;Erichsen and Schoeman 1992;Grove 2001a,b). Similar Þndings for other tephritids were reported in Hawaii, Mexico, Australia, and Argentina (Armstrong et al 1983, Armstrong 1991, De Lima 1995, Liquido et al 1995, Aluja et al 2004, Willink and Villagran 2007. Susceptibility of avocados to fruit ßies can depend on cultivar (Hennessey et al 1995, Aluja et al 2004, callus formation and regenerating tissue (Kay and Schroeder 1963, Smith 1973, Aluja et al 2004, and hardness (impenetrability/thickness) of the exocarp (Jones 1989, Oi andMau 1989) and may be a positive function of maturity (ripeness) (Oi and Mau 1989, Enkerlin et al 1993, Grove 2001a, Aluja et al 2004, the time of exposure before harvest (Pena et al 2006), or both.…”

“…The former is likely explained by the fact that C. capitata is known for its short aculei (Jones 1989) and Hass avocado for its thick exocarp (Newett et al 2002). The avocado is a climacteric fruit that does not ripen on the tree (De Villiers 2001), which together with its ability to develop calluses and regenerate tissue can contribute to make it less suitable for the reproduction of several fruit ßy species (Aluja et al 2004). However, other antixenosis and antibioses factors are also probably involved.…”

“…Variability of host status results were attributed to methodological differences between studies (Oi and Mau 1989) and highlighted the need for a robust testing method for fruit ßy host status. In February 2004, the U.S. Department of Agriculture (USDA) accepted very poor host status of preharvested Mexican avocados (Hass) to Anastrepha fruit ßies and a systems approach to mitigate its pest risk (Aluja et al 2004, Lambert 2004). Subsequently, guidelines for fruit ßy host status testing were provided by the Asia and PaciÞc Plant Protection Commission and the North American Plant Protection Organization (draft), who compiled regional standards for phytosanitary measures (RSPM) (Anonymous 2005(Anonymous , 2008.…”

Current Trends in Quarantine Entomology

“…Eradication programs targeting oriental fruit fly in Okinawa and the Mariana Islands are primarily based on male annihilation and involve distribution of coconut husks soaked in methyl eugenol (attractant) and malathion (insecticide) at a density of 400 blocks per km 2 . Eradication efforts for melon fly and mango fruit fly in these islands use the lure cuelure and the insecticide fipronil applied to fiberboard blocks at a rate of 1000 blocks per km 2 (78,125).…”

Is a mango just a mango? Testing within-fruit oviposition site choice and larval performance of a highly polyphagous fruit fly

“…We do note, however, that in this study we report only the fruit characteristic of firmness and TSS as possibly factors influencing oviposition site selection. In the field other factors such as fruit volatiles (Jang and Light 1991), wounds or cracks in the fruits (Papaj et al 1989), oviposition holes of conspecifics (Papaj and Alonso-Pimentel 1997), variation in available water, farming practices and plant diseases (Greany et al 1985;Liquido et al 1995;Aluja et al 2004) may all influence female oviposition preference.…”