Sources of resistance to Fusarium head blight within Syrian durum wheat landraces

Abstract

Fusarium head blight (FHB) is a destructive disease of wheat all over the world. FHB causes high economic losses for durum wheat because of the lack of resistance sources. Initially, sixty-eight Syrian landraces were tested in field conditions after inoculation to discriminate the most resistant and environmentally stable landraces. Further tests across a total of four environments revealed four landraces with a low mean FHB rating (19-25%) compared to common German durum varieties (56-60%) and an environmentally stable resistance. They are considered as promising resistance sources to FHB for introgression in the adapted durum wheat gene pool.Fusarium head blight (FHB) caused by Fusarium graminearum Schwabe (perfect stage: Gibberella zeae (Schw.) Petch) and other Fusarium species is a common disease in all cereals including maize. Common wheat (Triticum aestivum L.) is already more susceptible and provides higher contents of the mycotoxin deoxynivalenol than triticale and rye (Miedaner and Reinbrecht 2001), but durum wheat (Triticum turgidum L. var. durum) is even more sensitive (McMullen et al. 1997, Stack et al. 2003. Deployment of FHB-resistant cultivars is considered the most effective and cost-efficient strategy to combat this disease (Miedaner 1997). Sources of effective FHB resistance have not been found in adapted durum wheat (Chen et al. 2007). No resistant durum varieties are currently available (Buerstmayr et al. 2009). Attempts to transfer the highly effective resistance loci on chromosomes 5A and 3BS from the hexaploid Chinese landrace ÔSumaiÕ 3 to durum wheat had limited success only (Kumar et al. 2007; F. Lacoudre and L. Gervais, personal communications). Resistance to FHB in tetraploid wheat has been extensively evaluated in wild emmer wheat T. turgidum L. var. dicoccoides (AABB, 2n = 4· = 28). Buerstmayr et al. (2003) tested 151 accessions from different geographical areas in Israel and Turkey and identified eight accessions with moderate FHB resistance. Similarly, Oliver et al. (2008) tested 376 accessions of five subspecies of T. turgidum and found that 16 T. turgidum subsp. carthlicum and four T. turgidum subsp. dicoccum consistently exhibited resistance or moderate resistance to FHB that was much better than observed in actual durum varieties. Four major QTL for FHB in tetraploid wheat were identified so far on chromosomes 3A (Qfhs.ndsu-3AS, Otto et al. 2002), 7A (Qfhs.fcu-7AL; Kumar et al. 2007), 6BS and 2BL (Somers et al. 2006) with the three former QTL derived from wild relatives of durum wheat or emmer. Results of Somers et al. (2006) showed that FHB resistance QTL from wild relatives can be successfully transferred to adapted durum wheat. However, breeding would be much more effective if sources of FHB resistance were found in germplasm of cultivated durum wheat. It might be promising to search such sources in regions where cultivated wheat evolutionary developed, i.e. in the Fertile Crescent. Our objective aimed (i) to analyse Syrian landraces of durum wheat for their FHB resistance b...

QTL mapping of Fusarium head blight resistance in three related durum wheat populations

“…Most current durum wheat cultivars are highly susceptible and breeding progress is hampered by the narrow genetic variation for FHB resistance in durum wheat elite germplasm. Extensive screening of large germplasm collections identified only few durum landraces with improved levels of resistance (Elias et al 2005; Talas et al 2011; Huhn et al 2012). Alternative sources of resistance have been screened in the related tetraploid species of Triticum turgidum to identify resistance donors for breeding (Buerstmayr et al 2003b; Oliver et al 2007, 2008).…”

Meta-analysis of Resistance to Fusarium Head Blight in Tetraploid Wheat: Implications for Durum Wheat Breeding

“…Sources of resistance remain scarce despite efforts undertaken to discover FHB resistant lines: large collections of thousands of durum wheat accessions have been screened without identifying resistant lines (Elias et al 2005 ). Surveys on material from CIMMYT and ICARDA identifi ed only fi ve lines from a Tunisian source with moderate resistance to FHB spread (Huhn et al 2012 ) and four Syrian landraces with stable resistance (Talas et al 2011 ). The lack of resistance found in durum wheat may be attributed to historically low exposure to FHB and to the limited breeding efforts put into this relatively modern crop, which led to a narrow genetic base compared to other wheat species (Ban et al 2005 ;Oliver et al 2008 ).…”

Toward a better understanding of the genomic region harboring Fusarium head blight resistance QTL Qfhs.ndsu-3AS in durum wheat

“…Sources of FHB resistance have been found in durum wheat and its tetraploid relatives even though they are not as effective as those in common wheat Buerstmayr et al 2003;Cai et al 2005;Oliver et al 2007Oliver et al , 2008Ghavami et al 2011;Talas et al 2011;Ruan et al 2012;Zhang et al 2014). Molecular mapping has identified several wild emmer wheat (T. dicoccoides)-derived FHB resistance QTL, including Qfhs.ndsu-3AS on chromosome 3A (Otto et al 2002), Qfhs.fcu-7AL on 7A (Kumar et al 2007), and another on 6B .…”

“…Also, FHB resistance QTL has been detected in the durumrelated tetraploids T. cathlicum (Somers et al 2006) and T. dicoccum (Buerstmayr et al 2012;Zhang et al 2014). In addition, extensive screening of durum accessions for FHB resistance has identified several durum landraces with detectable resistance to the disease over the last few years (Ghavami et al 2011;Talas et al 2011;Zhang et al 2014). Some of these tetraploid-derived FHB resistance QTL mapped to the same genomic regions as those identified in hexaploids, suggesting collinearity of the resistance gene loci in tetraploids and hexaploids (Somers et al 2006;Buerstmayr et al 2012).…”