, Volume 95, Issue 1, pp 67–71 | Cite as

The inheritance and expression of leaf chlorosis associated with gene Sr2 for adult plant resistance to wheat stem rust

  • G.N. Brown


Sr2, an important source of durable resistance to the wheat stem rust pathogen, is linked with a distinctive seedling chlorosis gene sc. The expression of sc is sensitive to temperature and light. The chlorosis can be induced by inoculation with the stem rust or leaf rust pathogens and also develops on uninfected leaves of rusted plants. This chlorosis is an excellent marker for Sr2 which previously was best monitored by the appearance of pseudo-black chaff on glumes or upper stem or the expression of resistance. However, the latter are only detected late in the season on field-grown adult plants. Chlorosis was recessive in F1 hybrids, however, it segregated in a dominant manner in some F3 lines presumably due to the presence of modifying genes.

Sr2 durable resistance leaf chlorosis environmental effect Puccinia graminis f. sp. tritici, Puccinia recondita f. sp. tritici, Triticum aestivum leaf senescence linkage marker pseudo black chaff 


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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • G.N. Brown
    • 1
  1. 1.University of Sydney Plant Breeding Institute, CobbittyCamdenAustralia

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