Bromeliad targeted foliar treatments with Aqualuer® 20‐20 for hot spot mitigation using three hand sprayers against Aedes albopictus (Diptera: Culicidae)

摘要

INTRODUCTION Aedes albopictus (Skuse) is a potential urban vector of dengue, chikungunya, and Zika viruses (Derraik and Slaney 2015, Wilson and Chen 2015). Container‐inhabiting mosquitoes such as Ae. albopictus have opportunistic feeding patterns that are not restricted to crepuscular or evening times and invade containers in close association with humans (Skiff and Yee 2014, Chandel et al. 2016). Source reduction programs are effective in targeting these container‐inhabiting mosquitoes when carried out comprehensively (CDC 2016, Unlu et al. 2014), but such programs can become operationally costly and difficult to sustain, particularly when oviposition sites are cryptic and difficult to accurately survey (Unlu et al. 2013, Faraji and Unlu 2016). Combining source reduction with direct control methods, such as larviciding with residual control and adulticide treatments, can help mitigate costs by reducing labor requirements (Abramides et al. 2011, Fonseca et al. 2013). Aedes albopictus and other mosquitoes require harborage to protect them from harsh daytime conditions, which has been exploited with vegetative and foliage treatments using residual applications (Li et al. 2010, Unlu et al. 2017). Targeting foliage as a primary means of adult mosquito control has since been reinforced in densely vegetated suburban and rural landscapes in Queensland, Australia (Muzari et al. 2014) and echoed in Ae. albopictus eradication programs in the southern Australian islands where foliage treatments were prioritized for preventing the spread of Ae. albopictus (Muzari et al. 2017). Previous to this study, however, there has not been an attempt to see if treating bromeliads as a key harborage would result in reduction of mosquitoes in peridomestic environments. Bromeliads are key vegetative harborages and larval rearing sites, even when competing with peridomestic sources such as tires, pots, and plastic containers (Nordin et al. 2017). Aedes albopictus have also been found to consistently proliferate in bromeliad larval sites throughout the year in warm environments (Xue et al. 2018) and typically outcompete Ae. aegypti (L.) and native species in urbanized environments (Ceretti et al. 2016, Docile et al. 2017). Point‐source bromeliad treatment could provide similar benefits as foliar treatments while reducing the coverage needed to exert control on the peridomestic mosquito population. Also, the evaluation of application tools is a critical demand among mosquito control professionals (Conover et al. 2015) and is an ongoing objective for future work. To investigate both needs, three new hand‐held pump sprayer models were screened before being used to treat bromeliads to explore hand‐application tools for point‐source strategies and test the viability of bromeliad‐focused management for reducing Ae. albopictus in St. Augustine, FL.