Cyto genetic studies in wheat 12. lr 28 for resistance to puccinia recondita and sr 34 for resistance to puccinia graminis tritici
Mcintosh, R.A.; Miller, T.E.; Chapman, V.
Zeitschrift fuer Pflanzenzuechtung 89(4): 295-306
Two of the 5 independently-derived wheat lines possessing Yr8 for resistance to P. striiformis from Aegilops comosa also possess resistance of P. recondita. The single gene, Lr28, in 1 of these 2 lines was located in chromosome 4BL and showed recombination of 39.2 .+-. 2.7% with the centromere. Lr28 was apparently derived from A. speltoides used to disrupt the diploid pairing of wheat during the transfer of Yr8 to wheat chromosomes 2A or 2D. Lr28 is not present in alien addition and substitution lines possessing a pair of 2M chromosomes from A. comosa. Virulence in P. recondita populations for Lr28 has been found in Australia and North America. Alien addition and substitution lines with a pair of 2M chromosomes and various translocation derivatives possessing Yr8 also possess Sr34 for resistance to P. graminis tritici. Hence, Sr34 is sufficiently close to Yr8 in chromosome 2M to be concurrently transferred during translocation events. Sr34 conferred resistance to few Australian field cultures of this pathogen.