Abstract
The avocado seed borer, (ASB) Heilipus lauri Boheman 1845 (Coleoptera: Curculionidae) is an official quarantine pest limiting avocado production and fruit exports from Colombia to pest-free countries. To provide alternatives to manage ASB, the objective of this study was to determine the potential use of commercial strains of Beauveria bassiana and Metarhizium anisopliae as biological control agents of this pest. Pathogenicity of the strains was evaluated by complete immersion of the insect in a spore solution (direct inoculation) or by insect contact with inoculated fruit (indirect inoculation). The B. bassiana strain caused higher mortality (DF = 3, F = 25.7, P = 0.0002), showing an almost eight-fold increase, 55% and 79% mortality, for both concentrations used, 2.5 × 108 spores/mL or 2.5 × 109 spores/mL, respectively. Additionally, the B. bassiana strain showed shorter median survivorship using direct inoculation (15.8 to 8.7 days), a longer delay in the feeding initiation time (50 h), and a decrease in the fruit intake (Anti-feeding index above 50) after indirect inoculation. To our knowledge, this is the first report about the pathogenicity of a commercial B. bassiana strain against ASB in Colombia.
Highlights
The rapid increase of worldwide demand (FAOSTAT 2016) for avocado (Persea americana Mill) has positioned this crop in an important place in Colombian economy (AGRONET 2016)
Pathogenicity bioassay for commercial entomopathogenic formulations against avocado seed borer (ASB) adults In this assay adult beetles inoculated with B. bassiana showed mortalities of 55.7% (±9.12) and 79.31% (±5.97) for CC and C10, respectively
The median survival time (MST50) for direct inoculation decreased for all concentrations compared with the control, resulting in a decrease of at least two weeks (Table 2) and confirming the effect of concentration of B. bassiana on ASB survival
Summary
The rapid increase of worldwide demand (FAOSTAT 2016) for avocado (Persea americana Mill) has positioned this crop in an important place in Colombian economy (AGRONET 2016). In Colombia, ASB has been reported in the main regions of avocado production and has been found in a wide altitudinal range across the country (Corpoica 2013), which has led it to be classified as an official control pest and resulted in more rigorous control measurements to avoid its spread. Survival of this insect depends on the availability of avocado fruits (Diaz et al 2017) and it has shown a preference for the Hass cultivar (Medina-Quiroz et al 2010), the primary variety exported from Colombia. In Colombia, losses from ASB damage can reach up to 60% (Caicedo et al 2010; Medina-Quiroz et al 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
