Diversity of entomopathogenic fungi near leaf-cutting ant nests in a neotropical forest, with particular reference to Metarhizium anisopliae var. anisopliae

Sequence analysis of the rDNA intergenic spacer of Metarhizium strains isolated in Brazil

“…This group was characterized by the presence of three deletions (positions 217-229, 262-337 and 663-666) plus the 729 to 732 deletion also observed in Group B, and is the same grouping observed by Hughes et al (2004) and Pantou et al (2003) with the addition of isolates V90, CG644 and V288 from our study. Isolates CG644 and V288 were previously classified as M. anisopliae var.…”

“…All methods showed the formation of four well-supported groups (A, B, C and D). Groups A, B and C were reported (with identical names) in other studies (Hughes et al, 2004;Pantou et al, 2003) and Hughes et al (2004) also demonstrated that group A was subdivided in three subgroups (A1, A2 and A3). Our results support the existence of groups A, B and C, with the addition of a novel group (D), all with very high support values.…”

“…The utilization and the improvement of mycoinsecticides could be an alternative tool to overcome the considerable environmental impact and high economical costs posed by conventional insecticides (Roberts and St. Leger, 2004). The non-transcribed intergenic region (IGS) and the internal transcribed spacers (ITS) located in the nuclear ribosomal DNA (rDNA) gene cluster evolve rapidly and have been widely used as a tool to evaluate the genetic diversity within populations of fungi (Mavridou and Typas, 1998;Pantou et al, 2003;Hughes et al, 2004;Velásquez et al, 2007) and to resolve problems regarding the identification of species and isolates based on morphological characters (Milner et al, 1994;Driver et al, 2000;Iwen et al, 2002).…”

“…The utilization and the improvement of mycoinsecticides could be an alternative tool to overcome the considerable environmental impact and high economical costs posed by conventional insecticides (Roberts and St. Leger, 2004). The non-transcribed intergenic region (IGS) and the internal transcribed spacers (ITS) located in the nuclear ribosomal DNA (rDNA) gene cluster evolve rapidly and have been widely used as a tool to evaluate the genetic diversity within populations of fungi (Mavridou and Typas, 1998;Pantou et al, 2003;Hughes et al, 2004;Velásquez et al, 2007) and to resolve problems regarding the identification of species and isolates based on morphological characters (Milner et al, 1994;Driver et al, 2000;Iwen et al, 2002).Even though Metarhizium strains have been used in Brazil against a number of insect pests since the 1980s (Garcia et al, 1984), an evaluation on the intraspecific genetic variability of Metarhizium isolates from Brazil has not so far been performed. Since better characterization of the genetic variation within an entomopathogenic fungus population could be useful for the selection of more efficient isolates for biological control, the aim of this study was to assess the extent of genetic variability in the IGS region of Metarhizium strains with special attention placed on the Brazilian isolates.…”

Symbiont recognition of mutualistic bacteria by Acromyrmex leaf-cutting ants

“…Discrimination between native and foreign Pseudonocardia symbionts thus allows the ants to monitor and manipulate symbiont diversity within colonies and avoid competition between symbiont strains. This would further enable ants to distinguish beneficial from cheating Pseudonocardia strains as well as parasites and competitors that may enter ant colonies (for example, Escovopsis: Currie and Stuart, 2001; entomopathogenic fungi: for example, Hughes et al, 2004).…”