INHERITANCE OF RESISTANCE TO RHYNCHOSPORIUM-SECALIS IN SPRING BARLEY (HORDEUM-VULGARE L.)

The inheritance of durable resistance of selected spring barley variet ies to Rhynchosporium secalis was investigated. Data from the F-2 gene ration of a 4 x 4 diallel, without reciprocals and the F-4 generation of three crosses selected out of this diallel, suggest that resistance in this sample of varieties tested is complex in inheritance. Signifi cant additive effects were detected indicating that the resistance lev el of barley cultivars may be improved by the hybridisation of suitabl e varieties. However, the genes conferring resistance seem to be conce aled by the expression of one completely dominant resistance gene in o ur set of varieties. These results are partly in conflict with previou s results on the inheritance of resistance to R. secalis in the breede r's line '11258/2286(13)A' indicating that the effectiveness of this r esistance gene may be greatly influenced by the genetic background of the current population of R. secalis.