First report on the entomopathogenicity and virulence of Akanthomyces muscarius LY 72.14, a Yungas native fungal isolate, for Anastrepha fraterculus control

DANILOVICH, MARIANA E.; OVRUSKI, SERGIO M.; FARIÑA, JULIA I.; DELGADO, OSVALDO D.

BIOCONTROL SCIENCE AND TECHNOLOGY

TAYLOR & FRANCIS LTD

Año: 2020 p. 1 - 16

0958-3157

In this work, we report the entomopathogenic potential ofAkanthomyces muscarius LY72.14, a fungus isolated from a soilsample collected in the Southernmost sector of Las Yungas(Tucumán, Argentina) subtropical rainforest. The isolated fungusexhibited both pathogenicity and virulence in larvae, pupae andadults of the pestiferous fruit fly Anastrepha fraterculus, ability thatcould then be applicable for fruit pest biocontrol. Groups of 120late-third-instar larvae were inoculated by immersion with fourdifferent conidial concentrations of A. muscarius LY 72.14 rangingfrom 105 to 108 conidia mL−1. Mycosis was subsequently verifiedthrough different time lapses for larva (1?2 days), pupa (14 days)and adults (13 days). Results revealed adult stage as the mostsusceptible to fungal infection, with a mortality percentage of29.4 ± 3.2%, whilst pupal mortality reached 7.8 ± 1.2%. On theother hand, larval mortality was similar to the non-infected control(5.9 ± 1.4%). When 108 conidia mL−1 fungal inocula were used, thetotal host mortality (involving the three fly developmental stages)reached 53%. Virulence against fly adults was significantlydependent on high conidial concentrations, achieving a LC50value of 8.4 × 107 conidia mL−1, with a similar killing effectivenesspattern (43?45%) among 107 and 108 conidial concentrations. Thepromising herein demonstrated biocontrol potential ofA. muscarius LY 72.14 to effectively infect and kill A. fraterculusunder lab-condition assays, makes relevant to evaluate this nativefungal isolate under field-cage and open-field conditions toweight the possibilities for biocontrol massive usage and itstentative application for integrated plague management.