Inheritance and chromosomal location of Septoria passerinii resistance introgressed from Hordeum bulbosum into Hordeum vulgare

Abstract

Septoria speckled leaf blotch (SSLB), caused by Septoria passerinii, has become one of the most serious diseases of barley in the Upper Midwest region of the USA. The recombinant line 36L5 derived from a backcross of the susceptible barley cultivar ÔEmirÕ and a resistant Hordeum bulbosum parent Cb2920/4/Colch was found to be resistant to S. passerinii. Two doubled haploids derived from 36L5 were backcrossed to cv. ÔEmirÕ to obtain two BCF 2 populations for determining the inheritance of resistance to S. passerinii. BCF 2 progeny and BCF 2:3 families were evaluated at the seedling stage in the greenhouse for reaction to S. passerinii. BCF 2 progeny and BCF 2:3 families from both crosses segregated 3 : 1 (resistant : susceptible), and 1 : 2 : 1 (resistant : segregating : susceptible), respectively, indicating that the H. bulbosum-derived SSLB resistance is conferred by a single dominant gene. The H. bulbosum introgressions were positioned on chromosome 4HL by genomic and fluorescent in situ hybridizations (GISH and FISH, respectively) and by Southern hybridization with the rye repetitive sequence pSc119.2. These findings indicate that SSLB resistance in H. bulbosum has the potential to be transferred and utilized in barley breeding programs.

Discovery of a functional Mycosphaerella teleomorph in the presumed asexual barley pathogen Septoria passerinii

“…Since then, SSLB has been reported around the globe in such areas as the Upper Midwest region of the United States, the Prairie Provinces of Canada, Northern Europe, Northern Africa, Western Asia, and Australia (Cunfer and Ueng, 1999;Mathre, 1997). Over the past decade, SSLB epidemics have increased in frequency, and SSLB has become one of the most important, albeit sporadic, foliar diseases of barley in the United States and in Canada (Mathre, 1997;Steffenson, 2003;Toubia-Rahme et al, 2003). Yield losses of up to 38% have been reported in Minnesota and North Dakota, with similar reports of losses up to 20% in Canada (Green and Bendelow, 1961;Toubia-Rahme and Steffenson, 1999).…”

Validation of Quantitative Trait Loci for Multiple Disease Resistance in Barley Using Advanced Backcross Lines Developed with a Wild Barley

“…Many resistance sources have been identified in both cultivated and wild barley (Fetch et al, 2003;Metcalfe et al, 1977Metcalfe et al, , 1978Legge et al, 1996;Rasmusson and Rogers, 1963;Toubia-Rahme et al, 2003;Toubia-Rahme and Steffenson, 2004). vulgare 3 H. bulbosum RIL population (Toubia-Rahme et al, 2003). One derived from cultivated barley was localized on chromosome 4(4H) in a H. v. subsp.…”

Barley

“…However, strong crossability barriers exist to the 30 species of Hordeum belonging to the tertiary gene pool (Pickering and Johnston 2005 ). Successful reports on transfer of resistances against several threats like powdery mildew (Pickering et al 1995 ), leaf rust (Pickering et al 1998 ), Septoria speckled leaf blotch (Toubia-Rahme et al 2003 ) and barley yellow mosaic virus (Ruge et al 2003 ;Ruge-Wehling et al 2006 ) from H. bulbosum into H. vulgare are available.…”