Turkish barley landraces resistant to net and spot forms of <em>Pyrenophora teres</em>

Abstract

Pyrenophora teres is an important pathogen of barley. The pathogen has two biotypes: Pyrenophora teres f. teres, which causes the net type of net blotch, and P. teres f. maculata causing the spot type of net blotch. Turkey is an important gene centre of barley and has a rich barley landrace population. Finding disease resistant barley germplasm has potential for world agriculture. Three virulent Pyrenophora teres f. maculata (Ptm) isolates and three virulent Pyrenophora teres f. teres (Ptt) isolates were tested for their pathogenicity to 198 barley landraces, and landraces resistant to both forms of the pathogen were identified. Thirteen landraces (numbered 17, 40, 71, 98, 101, 103, 104, 143, 162, 167, 171, 183 and 185) were resistant to the Ptm isolates and seven (numbered 18, 21, 22, 24, 40, 71 and 153) were resistant to the Ptt isolates. Two landraces (40 and 71) were resistant to all six P. teres isolates. In addition, several of the landraces exhibited reactions to one or two isolates of Ptt or Ptm, in the resistant to moderately resistant range. Using disease resistant host genotypes will help to reduce the use of disease control chemicals, and with development of efficient host resistance strategies to combat net blotch  diseases. These landraces could be used as sources of resistance for barley breeding.