Genetic characterization, pathogenicity and benomyl susceptibility of Lecanicillium fungal isolates from Argentina

MANFRINO, R.G..; SCHUSTER, C.; SAAR, K.; CLAUDIA C. LOPEZ-LASTRA; ANDREAS LECLERQUE; ANDREAS LECLERQUE

JOURNAL OF APPLIED ENTOMOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2018

0931-2048

The aim of this study was to investigate biological and molecular characteristics ofLecanicillium strains isolated from Hemipteran hosts in Argentina. Morphology‐basedtaxonomic characterization together with molecular taxonomy based on rRNA operoninternal transcribed spacer (ITS), mitochondrial nad1 gene, and nuclear ef1agene sequences resulted in the assignment of nine out of ten isolates to theLecanicillium lecanii sensu lato complex. However, whereas several isolates were thusunequivocally characterized as Lecanicillium muscarium or Lecanicillium longisporum,species assignment was not possible for three isolates that might represent a newspecies within the L. lecanii s.l. complex. We found two group‐I introns on 18S and28S rRNA gene on only one isolate. Pathogenicity tests were conducted against thepeach aphid using conidial suspensions (1 × 107 conidia/ml), and the Kaplan?Meieranalysis was performed to evaluate the survival of Myzus persicae. Lecanicillium longisporumCEP 155 and L. muscarium CEP 182 were significantly more pathogenic toM. persicae than all the Lecanicillium isolates causing aphid mortalities >85%.Determination of susceptibility to the benzimidazole fungicide benomyl revealed importantdifferences between Lecanicillium strains. The inhibitory effect of benomylappeared less pronounced for the L. muscarium fungal isolates than for those belongingto a different taxon. Based in our results, the best candidate strain as microbialbiological control agent against M. persicae is L. muscarium CEP 182. However, furtherresearch under field conditions in greenhouses should be done in order to confirmthe compatibility of entomopathogenic fungi and fungicides within an IPMstrategy.