Genetic diversity of Hirsutella thompsonii isolates from Thailand based on AFLP analysis and partial beta-tubulin gene sequences

Abstract

Amplified fragment length polymorphism (AFLP) was used to investigate polymorphism among 43 Hirsutella thompsonii isolates (33 from Thailand) obtained from various mite species. The outgroups were an unidentified Hirsutella isolate along with Hirsutella nodulosa and Hirsutella kirchneri. Phylogenetic analyses of the AFLP data showed significant variation among isolates and the existence of three H. thompsonii clades. We also investigated the isolates using PCR with specific primers for the Hirsutella exotoxin gene Hirsutelin A (HtA) and 18 of these isolates were used for sequencing of the partial b-tubulin gene. Phylogenetic analyses of b-tubulin sequences showed two distinct H. thompsonii clades, one of which included AFLP clades I and II. For both markers grouping of the H. thompsonii isolates was not related to either host mite species or geographical origin, although for the HtA gene one clade contained only isolates with no detectable HtA band. These results confirm the high intraspecific polymorphism of H. thompsonii, and maximum likelihood analysis showed no monophyletic group within this species. To refine the taxonomy of this genus other studies should be undertaken using additional molecular markers and several other Hirsutella isolates.

Genetic diversity of the root‐knot nematode Meloidogyne enterolobii and development of a SCAR marker for this guava‐damaging species

“…and fungi (Suazo & Hall, 1999;Boucias et al, 2000;Tigano et al, 2006). However, the level of polymorphism detected here with AFLP was lower than that with the ISSR and RAPD markers, which was quite unexpected compared to previous studies (Semblat et al, 1998;Fargette et al, 2005).…”

Ophiocordyceps myrmicarum, a new species infecting invasive Myrmica rubra in Maine

“…Primer combinations used for amplifications were (i) NS1 and NS4 (White et al, 1990) for nuclear small subunit (nucSSU) ribosomal DNA (rDNA), (ii) LR0R and LR5 (Rehner and Samuels, 1994;Vilgalys and Hester, 1990) for nuclear large subunit (nucLSU) rDNA, (iii) ITS1 and ITS4 (White et al, 1990) for partial internal transcribed spacer 1 (ITS1), 5.8S rDNA, and internal transcribed spacer 2 (ITS2), (iv) pairs 983F/1567R and 1577F/2218R (Rehner and Buckley, 2005) for tef1a, (v) RPB1-313F (5 0 -YTGGAR-ATTGTCTGCCAYAAY-3 0 ) and RPB1CrW (5 0 -CCNGCDATNTCRTTRTC-CATRWA-3 0 ), which was derived from RPB1Cr (Castlebury et al, 2004) for rpb1, and (vi) b-tubF and b-tubR (Tigano et al, 2006) for b-tubulin.…”

Phylogeny and morphology of Hirsutella tunicata sp. nov. (Ophiocordycipitaceae), a novel mite parasite from Peru

“…PCR was performed in a thermal cycler (BioRad, Hercules, USA) with the following cycles: 1 initial cycle at 95 C for 7 min; 35 cycles with 30 s at 94 C, 30 s at 55 C and 1 min at 72 C, with a single final extension cycle at 72 C for 4 min. For PCR amplification of the b-tubulin gene, the primers btubF and btubR were used, using amplification conditions developed for H. thompsonii (Tigano et al 2006). All amplicons were sequenced by an available commercial service (Microgen, Seoul, South Korea).…”

“…Not all Hirsutella species are available in public collections, and in some cases (i.e., H. piligena, described from a fur-like substrate) the original description does not provide sufficient information for reisolation, revision or re-description with modern taxonomic criteria. Available genetic data for a number of Hirsutella species include mainly partial sequences of rRNA and b-tubulin genes (Tigano et al 2006), as well as translation elongation factor-1 a or DNA-dependent RNA polymerase (Sung et al 2007).…”