Intraspecific differentiation of Chilean isolates of the entomopathogenic fungi Metarhizium anisopliae var. anisopliae as revealed by RAPD, SSR and ITS markers

Abstract

The genus Metarhizium consists of a diverse group of asexual entomopathogenic fungi, which have a wide geographical distribution. The Chilean National Agricultural Research Institute (Instituto de Investigaciones Agropecuarias - INIA, Quilamapu Chile) has collected about 350 isolates of Metarhizium anisopliae var. anisopliae from central and southern Chile. These isolates have been partially characterized using morphological traits such as conidia size and shape, colony color, growth pattern and the efficiency of the isolates in controlling specific pests. However, further characterization with molecular markers could detect differences in DNA which could help to better understand the genetic diversity and structure of Chilean populations of this fungus. We analyzed approximately 10% of the INIA collection (39 isolates selected at random) collected from different geographical origins using the polymerase chain reaction (PCR)-random amplified polymorphic DNA (RAPD) method, simple sequences repeat (SSR or microsatellites) analysis and the PCR-restriction fragment length polymorphism (RFLP) assay of internal transcribed spacer (ITS)-rDNA sequences. The RAPD data revealed high genetic diversity in this fungus and an average of 41% of similarity while SSR analysis detected 45.2% similarity and the ITS markers 70.2% similarity. For the three molecular markers, this diversity was not associated with the geographical origin of these isolates

Characterization and activity of entomopathogenic fungi isolates against “paraguay tea ampul” (Gyropsylla spegazziniana) (Lizer & Trelles) (Hemiptera: Psyllidae)

“…The proportion of monomorphic loci between the most virulent isolates was low (16.2%). Although some studies have reported a relationship between the molecular profile of isolates of entomopathogenic fungi and their initial host (CARNEIRO et al, 2008;OLIVEIRA et al, 2011) or geographical origin (FERNANDES et al, 2009), such a relationship was not found in the present study, either through analysis of the rDNA-ITS region or the groups generated via RAPD analysis, similar to the results of Becerra-Velásquez et al (2007) and Mendonça et al (2012).…”

Biological insect control using Metarhizium anisopliae: morphological, molecular, and ecological aspects

“…In the present study, isolates of M. anisopliae could be grouped according to their geographical origins, although no signifi cant correlations were observed in terms of their hosts. VELÁSQUEZ et al (2007) observed that there were no associations between the diversity of isolates of M. anisopliae from different regions in Chile and their geographic origins. ITS-RFLP was used to defi ne specifi c primers that could be used to detect and identify M. anisopliae var.…”

“…These markers were used to examine polymorphism in M. anisopliae, but the primers used to examine samples derived from soil cores from different regions in Chile (VELÁSQUEZ et al, 2007) and numerous countries in Asia and Europe (FREED et al, 2010) were not effi cient in detecting informative polymorphisms. To the contrary of microsatellite analysis, the ISSR technique amplifi es fragments located between two repetitive regions present in various genomes (FALEIRO 2007), known as inter-microsatellite regions.…”

Análisis genético de Beauveria y Metarhizium tropicales asociados a insectos en caña de azúcar

“…Una manera efectiva de caracterizar la diversidad para la protección de recursos biológicos, es por medio de marcadores moleculares. En Metarhizium y Beauveria se han aplicado marcadores moleculares tipo amplificación aleatoria de ADN polimórfico (RAPD, por sus siglas en inglés), y repetición de secuencias discretas (SSR, por sus siglas en inglés) o microsatélites (Castrillo et al, 2003;Rehner y Buckley, 2003;Aquino-De-Muro et al, 2005;Becerra-Velásquez et al, 2007;Freed et al, 2011;Zhang et al, 2016). Aunque cualquiera de estos sistemas de marcadores es efectivo para caracterización, los RAPD, ISSR y AFLP amplifican numerosos segmentos desconocidos y, rara vez, generan perfiles genéticos exclusivos a un individuo.…”