Specialisation of Rhynchosporium secalis (Oud.) J.J. Davis infecting barley and rye

Abstract

Fifty-five isolates of Rhynchosporium secalis from Hordeum vulgare and 34 isolates from Secale cereale were compared for growth on different nutrient media, effect of temperature on growth and morphology of colonies. The pathogenicity of the isolates was assessed on 10 rye varieties, 10 triticale varieties and the susceptible barley variety Gambrinus. The triticale varieties differed in the number of rye chromosomes in the genome. Isozymes of R. secalis isolated from infected leaves of barley and rye were compared. The RAPD-PCR method was used for comparison of isolates on DNA-markers. The analysis indicated two specialised forms of the fungus; each of them able to develop only on its original host.

Keywords

• rhynchosporium secalis
• barley
• rye
• specialisation