ISSN:
1432-0983
Keywords:
Ascochyta
;
Pea
;
Isozymes
;
rDNA spacers
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Isolates of three closely related pea pathogens,Ascochyta pisi, Ascochyta pinodes (teleomorphMycosphaerella pinodes) andPhoma medicaginis var. pinodella, were compared by means of isozyme analysis and restriction fragment length polymorphisms (RFLP) of amplified rDNA spacers. Three enzyme systems differentiatedA. pisi fromM. pinodes andP. m. pinodella. The internal transcribed spacers (ITSs) of the three fungi showed no intraspecific and very little interspecific variation after digestion with 12 endonucleases. Digestion of the intergenic spacer (IGS) withHinfI, andSau3A revealed uniformity inA. pisi patterns which consistently differed from those ofM. pinodes andP. m. pinodella. No clear distinction could be made between the latter two fungi which both showed intraspecific variability. Both biochemical and molecular markers thus discriminated between twoAscochyta species. The results also indicated a closer relationship between two organisms belonging to different genera (Ascochyta andPhoma) than between two species of the same genus (Ascochyta).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02221583