A double-stranded DNA virus was isolated from hyperplasic salivary glands of male and female houseflies, Musca domestica L. (Diptera: Muscidae), collected from a dairy in Alachua County, Florida, U.S.A. Sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE) of this housefly salivary gland hyperplasia (SGH) virus revealed the presence of two major and eight minor structural polypeptides. Restriction endonuclease analysis indicated that the c. 137 kilobase pair DNA was double-stranded. Weekly, sweep-net sampling of the fly population throughout the season (May-October, 1991) showed that 1.5-18.5% of the dissected flies possessed hyperplasic salivary glands. The virus replicated within the nuclei of the salivary gland cells and was transmitted per os to newly-emerged healthy adult flies.

Specialized Pheromone and Lure Application Technology (SPLAT) methyl eugenol (ME) and cue-lure (C-L) "attract-and-kill" sprayable formulations containing spinosad were compared with other formulations under Hawaiian weather conditions against oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), respectively. Field tests were conducted with three different dispensers (Min-U-Gel, Acti-Gel, and SPLAT) and two different insecticides (naled and spinosad). SPLAT ME with spinosad was equal in performance to the standard Min-U-Gel ME with naled formulation up to 12 wk. SPLAT C-L with spinosad was equal in performance to the standard Min-U-Gel C-L with naled formulation during weeks 7 to12, but not during weeks 1-6. In subsequent comparative trials, SPLAT ME + spinosad compared favorably with the current standard of Min-U-Gel ME + naled for up to 6 wk, and it was superior from weeks 7 to 12 in two separate tests conducted in a papaya (Carica papaya L.) orchard and a guava (Psidium guajava L.) orchard, respectively. In outdoor paired weathering tests (fresh versus weathered), C-L dispensers (SPLAT + spinosad, SPLAT + naled, and Min-U-Gel + naled) were effective up to 70 d. Weathered ME dispensers with SPLAT + spinosad compared favorably with SPLAT + naled and Min-U-Gel + naled, and they were equal to fresh dispensers for 21-28 d, depending on location. Our current studies indicate that SPLAT ME and SPLAT C-L sprayable attract-and-kill dispensers containing spinosad are a promising substitute for current liquid organophosphate insecticide formulations used for areawide suppression of B. dorsalis and B. cucurbitae in Hawaii.

Studies were conducted in 2007 and 2008 in Hawaii, USA to quantify attraction and feeding responses resulting in mortality of the male oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), to a novel male annihilation treatment (MAT) formulation consisting of specialized pheromone and lure application technology (SPLAT) in combination with methyl eugenol (ME) and spinosad (=SPLAT‐MAT‐ME with spinosad) in comparison with Min‐U‐Gel‐ME with naled (Dibrom). Our approach involved a novel behavioral methodology for evaluation of slow‐acting reduced‐risk insecticides. Methyl eugenol treatments were weathered for 1, 2, 4, and 8 weeks in California, USA, and shipped to Hawaii for bioassays. In field tests involving bucket traps to attract and capture wild males, and in toxicity studies conducted in 1 m3 cages using released males of controlled ages, SPLAT‐MAT‐ME with spinosad performed similar to or outperformed the standard formulation of Min‐U‐Gel‐ME with naled for material aged for up to 8 weeks in the 2008 tests. In laboratory feeding tests in which individual males were exposed for 5 min to the different ME treatments, mortality induced by SPLAT‐MAT‐ME with spinosad recorded at 24 h did not differ from that caused by Min‐U‐Gel ME with naled at 1, 2, and 4 weeks. Spinosad has low contact toxicity, and when mixed with SPLAT offers a reduced‐risk alternative for control of B. dorsalis, without many of the negative effects to humans and non‐targets of broad‐spectrum contact poisons such as naled. Our results indicate that SPLAT‐MAT‐ME with spinosad offers potential for control of males in an area‐wide integrated pest management (IPM) system without the need for conventional organophosphates.

No abstract

Specialized Pheromone and Lure Application Technology (SPLAT) methyl eugenol (ME) and cue-lure (C-L) "attract-and-kill" sprayable formulations containing spinosad were compared with other formulations under Hawaiian weather conditions against oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), respectively. Field tests were conducted with three different dispensers (Min-U-Gel, Acti-Gel, and SPLAT) and two different insecticides (naled and spinosad). SPLAT ME with spinosad was equal in performance to the standard Min-U-Gel ME with naled formulation up to 12 wk. SPLAT C-L with spinosad was equal in performance to the standard Min-U-Gel C-L with naled formulation during weeks 7 to12, but not during weeks 1-6. In subsequent comparative trials, SPLAT ME + spinosad compared favorably with the current standard of Min-U-Gel ME + naled for up to 6 wk, and it was superior from weeks 7 to 12 in two separate tests conducted in a papaya (Carica papaya L.) orchard and a guava (Psidium guajava L.) orchard, respectively. In outdoor paired weathering tests (fresh versus weathered), C-L dispensers (SPLAT + spinosad, SPLAT + naled, and Min-U-Gel + naled) were effective up to 70 d. Weathered ME dispensers with SPLAT + spinosad compared favorably with SPLAT + naled and Min-U-Gel + naled, and they were equal to fresh dispensers for 21-28 d, depending on location. Our current studies indicate that SPLAT ME and SPLAT C-L sprayable attract-and-kill dispensers containing spinosad are a promising substitute for current liquid organophosphate insecticide formulations used for areawide suppression of B. dorsalis and B. cucurbitae in Hawaii.