TRANSFER OF THE CHROMOSOME CONFERRING MILDEW RESISTANCE FROM AEGILOPS-SHARONENSIS EIG INTO TRITICUM-AESTIVUM L

It is quite difficult of transfer Aegilops sharonensis chromosomes int o wheat using the standard technique, because of a gametocidal effect of the chromosome 4S1. A number of lines of common wheat variety Auror a containing 21II in meiosis and posessing some particular characters of Ae. sharonensis were produced from the genome-substituted form Auro sis (tetra-Aurora - Ae. sharonensis). Eight lines resistant to powdery mildew lines were, self-crossed and crossed with Aurora. The study of chromosome pairing and mildew resistance in the hybrids showed that a ll substituted lines had the same alien chromosome. However, some line s differed from the others in a wheat chromosome which was replaced by the alien one. To identify which of Ae. sharonensis chromosome was su bstituted for wheat homoeologue from the D genome, two substitution li nes Aurora were crossed with the substitution lines Chinese Spring: 1E (1D), 2E(2D), 3E(3D), 4S1(4D), 5U(5D), 6R(6D), 7E(7D). The results of chromosome pairing study in the hybrids showed that in one of the line s, Ae. sharonensis chromosome substituted the wheat chromosome 6D, whi le in the other line substitution occurred in no D genome. This chromo some may be designated 6S1 or 6S(sh). It is a satellite-bearing chromo some, carries a dominant gene for powdery mildew resistance, brings ab out the development of awns in the uppermost spikelets of the ears and antocyan colour of the upper part of stems.