'Plant Breeding: Sustaining the Future' Abstracts of the XVIth EUCARPIA Congress, Edinburgh, Scotland, 10-14 September 2001 GENETICS OF WHEAT RESISTANCE TO DARK BROWN LEAF SPOT BLOTCH L.G. TYRYSHKIN, N.A. SHISHELOVA NI Vavilov Institute of Plant Industry, St Petersburg, Russia

Hybridological analysis was used to study genetics of resistance in 6 wheat (Triticum aestivum L.) collection samples (181-5, Spica, IWWR, Mexico 120, lines of Penjamo with Aegilops squarrosa and Ae. Cylindrica Shoem.). Different mode of inheritance of resistance to highly aggressive strain T was shown: oligogenic for collection samples (one dominant nonallelic gene in each sample) and polygenic for somaclonal lines. Minor and major genes of studied genotypes controlled decreasing of spot size and/or spot number. No differential interaction with the pathogen isolates was found in somaclones; resistance in collection samples (except 181-5) could be easily overcome by the pathogen at least at 1-2 leaves stage of plant growth.