Characterization ofColletotrichum acutatumCausing Anthracnose of Anemone (Anemone coronariaL.)

Abstract

Anthracnose, or leaf-curl disease of anemone, caused by Colletotrichum sp., has been reported to occur in Australia, western Europe, and Japan. Symptoms include tissue necrosis, corm rot, leaf crinkles, and characteristic spiral twisting of floral peduncles. Three epidemics of the disease have been recorded in Israel: in 1978, in 1990 to 1993, and in 1996 to 1998. We characterized 92 Colletotrichum isolates associated with anthracnose of anemone (Anemone coronaria L.) for vegetative compatibility (72 isolates) and for molecular genotype (92 isolates) and virulence (4 isolates). Eighty-six of the isolates represented the three epidemics in Israel, one isolate was from Australia, and five isolates originated from western Europe. We divided these isolates into three vegetative-compatibility groups (VCGs). One VCG (ANE-A) included all 10 isolates from the first and second epidemics, and 13 of 62 examined isolates from the third epidemic in Israel, along with the isolate from Australia and 4 of 5 isolates from Europe. Another VCG (ANE-F) included most of the examined isolates (49 of the 62) from the third epidemic, as well as Colletotrichum acutatum from strawberry, in Israel. Based on PCR amplification with species-specific primers, all of the anemone isolates were identified as C. acutatum. Anemone and strawberry isolates of the two VCGs were genotypically similar and indistinguishable when compared by arbitrarily primed PCR of genomic DNA. Only isolate NL-12 from The Netherlands, confirmed as C. acutatum but not compatible with either VCG, had a distinct genotype; this isolate represents a third VCG of C. acutatum. Isolates from anemone and strawberry could infect both plant species in artificial inoculations. VCG ANE-F was recovered from natural infections of both anemone and strawberry, but VCG ANE-A was recovered only from anemone. This study of C. acutatum from anemone illustrates the potential of VCG analysis to reveal distinct subspecific groups within a pathogen population which appears to be genotypically homogeneous by molecular assays.

Effect of Ammonia Production by Colletotrichum gloeosporioides on pelB Activation, Pectate Lyase Secretion, and Fruit Pathogenicity

“…We made four Nit mutants, which are unable to utilize NO 3 as a nitrogen source (10). These mutants grew well in the primary medium, which contains peptone and yeast extract as potential nitrogen sources.…”

“…The accumulation of large amounts of ammonia in the decaying tissue ensures transformation from the quiescent biotrophic to the necrotrophic stage of Colletotrichum colonization. (10). When transferred to secondary medium, the nit mutants were grown in the presence of 3 mM glutamate amended with amounts of KNO 3 similar to those described above.…”

Coelomycete systematics with special reference to Colletotrichum

“…These procedures together with the targets they probe comprise isozyme analyses of 11, 13, or 19 enzyme systems on the protein level (Bonde et al 1991;Meijer et al 1994;Kaufman and Weideman 1996); sequence analyses of the PCR-amplifi ed internal transcribed spacer (ITS) region of rDNA (Mills et al 1992;Rehner and Uecker 1994;Sherriff et al 1994Sherriff et al , 1995Sreenivasaprasad et al 1996;Johnston and Jones 1997;Zhang et al 1997a;Uddin et al 1998); amplifi ed fragment length polymorphisms (AFLPs) of genomic DNA (Majer et al 1996;O'Neill et al 1997); restriction fragment length polymorphisms (RFLPs) of rDNA, mitochondrial DNA (mtDNA), and genomic DNA (Braithwaite et al 1990;Vaillancourt and Hanau 1992;Hodson et al 1993;Alahakoon et al 1994;Riccioni et al 2003); RFLPs and DNA-DNA hybridization (Liyanage et al 1992;Bernstein et al 1995;Brown et al 1996); primer PCR-initiated random amplifi ed polymorphic DNAs (RAPDs) or AT-rich DNA analyses of genomic DNA (Welsh and McClelland 1990;Williams et al 1990;Guthrie et al 1992;Vaillancourt and Hanau 1992;Freeman et al 1993;Blakemore et al 1994;Trigiano et al 1995;Fernandez and Hanlin 1996;Freeman and Katan 1997;Mackie and Irwin 1998;Chakraborty et al 1999); species-specifi c primer analysis of rDNA-ITS1 region Adaskaveg and Hartin 1997;Freeman et al 2000); and high mobility group (HMG)-encoding sequence of the MAT1-2 mating type sequence …”

“…Furthermore, vegetative compatibility group (VCG) analysis offers a system ancillary or collateral to RAPD for exploration of genetic distinctness or diversity and relationships between several morphological groups recognized within a pathogen population that appears to be genotypically homogeneous by molecular assays (Lardner et al 1999;Freeman et al 2000;Katan 2000;Nitzan et al 2002).…”

“…Nevertheless, species names of Colletotrichum are no longer of much signifi cance because of their extensive host range, intermediate forms, and morphological and pathological variations (Du et al 2005) relative to environmental infl uences (Bailey and Jeger 1992;Freeman et al 2000).…”