Molecular studies on intraspecific diversity and phylogenetic position of Coniothyrium minitans

Abstract

Simple sequence repeat (SSR)-PCR amplification using a microsatellite primer (GACA) % and ribosomal RNA gene sequencing were used to examine the intraspecific diversity in the mycoparasite Coniothyrium minitans based on 48 strains, representing eight colony types, from 17 countries world-wide. Coniothyrium cerealis, C. fuckelii and C. sporulosum were used for interspecific comparison. The SSR-PCR technique revealed a relatively low level of polymorphism within C. minitans but did allow some differentiation between strains. While there was no relationship between SSR-PCR profiles and colony type, there was some limited correlation between these profiles and country of origin. Sequences of the ITS 1 and ITS 2 regions and the 5n8S gene of rRNA genes were identical in all twenty-four strains of C. minitans examined irrespective of colony type and origin. These results indicate that C. minitans is genetically not very variable despite phenotypic differences. ITS and 5n8S rRNA gene sequence analyses showed that C. minitans had similarities of 94 % with C. fuckelii and C. sporulosum (which were identical to each other) and only 64 % with C. cerealis. Database searches failed to show any similarity with the ITS 1 sequence for C. minitans although the 5n8S rRNA gene and ITS 2 sequences revealed an 87 % similarity with Aporospora terricola. The ITS sequence including the 5n8S rRNA gene sequence of Coniothyrium cerealis showed 91 % similarity to Phaeosphaeria microscopica. Phylogenetic analyses using database information suggest that C. minitans, C. sporulosum, C. fuckelii and A. terricola cluster in one clade, grouping with Helminthosporium species and ' Leptosphaeria ' bicolor. Coniothyrium cerealis grouped with Ampelomyces quisqualis and formed a major cluster with members of the Phaeosphaeriacae and Phaeosphaeria microscopica.

Intraspecific diversity: adaptive differentiation of Picea mongolica W. D. Xu ecotypes

“…(Cui et al, 2000), Arabidopsis thaliana (L.) Heynh. (Baud et al, 2002;Ludwig-Mül-ler, 2007) and Coniothyrium minitans W. A. Campbell (Muthumeenakshi et al, 2001). Hence, this kind of ecotypes can be called genetic differentiation (Hufford and Mazer, 2003).…”

Molecular cloning, characterization and expression analysis of a pacC homolog in the mycoparasite Coniothyrium minitans

“…de Bary, an omniovorous plant pathogenic fungus. Muthumeenakshi et al (2001) reported that C. minitans is closely related to ascomycetous fungi based on phylogenetic analysis of DNA sequences of internal transcribed spacer regions (ITS1 and ITS2) and the 5.8S rRNA gene. Numerous studies showed that C. minitans is a promising biocontrol agent of S. sclerotiorum (de Vrije et al 2001;Whipps et al 2008), Sclerotinia minor Jagg.…”

Use of Coniothyrium minitans as a biocontrol agent and some molecular aspects of sclerotial mycoparasitism

“…There are numerous phenotypes differing in colony morphology and a number of other biological characteristics (Sandys-Winsch et al 1993;Jones and Stewart 2000;Grendene et al 2002) but ability to parasitize sclerotia of S. sclerotiorum remains a key feature. Some isolates have begun to be characterised using molecular procedures such as random amplification of polymorphic DNA (RAPD) and simple sequence repeat (SSR) -PCR profiling, and rRNA gene sequencing (Goldstein et al 2000;Ridgway and Stewart 2000;Muthumeenakshi et al 2001;Grendene et al 2002). Recently, based on anamorphic characteristics seen in vitro, and maximum parsimony analysis of ITS and SSU nrDNA sequences, C. minitans was reclassified as Paraconiothyrium minitans (Verkley et al 2004).…”