Exploiting genetic resources to develop breeding tools for anthracnose resistance screening in lentil

Saskatchewan is by far the largest lentil exporter in the world and in some years, the largest producer.  Lentil anthracnose is currently the most important lentil disease in Saskatchewan. In a project about to be completed on molecular aspects of this pathogen, we generated an extensive library of genes activated by the anthracnose fungus and by lentil during the infection process. In order to fully benefit from the investment made in this NSERC-CRD, we received one-year funding to confirm the function of a number of genes in the anthracnose fungus, Colletotrichum truncatum, that we have identified and believe to be involved in virulence of the fungus,

to systematically screen the library of genes activated by the lentil plant during the infection process and identify defense genes that can be exploited for resistance breeding, and to screen germplasm currently identified as parents in crosses for the presence of those defense-related genes, in particular in material that could potentially have resistance genes to the more aggressive race 0.

Yield losses due to anthracnose, caused by the fungal pathogen Colletotrichum truncatum, currently the most prominent disease in Canadian lentil, can reach up to 70 % (Morrall et al. 1991) which is equivalent to a direct financial loss of around $ 300 per ha for a lentil producer, not including additional losses for down-grading of the remaining crop due to poor quality. Fungicide costs are estimated at $49 per ha with an average use of 45% in lentil (Gray & Scott 2003). Based on the estimated area seeded to lentil in 2010, the use of fungicides represents an increase in production cost by nearly $66 million, which could be significantly reduced by improving resistance in lentil cultivars. Tight rotations with increased years of lentil production in fields in the lentil growing areas of the province have increased the risk of major anthracnose epidemics. Furthermore, a survey of a field near Dysart with moderate disease levels in 2008  (with generally low disease pressure in the province) revealed that all isolates tested belonged to the more aggressive race 0 to which all currently available lentil cultivars are susceptible. Hence, the development of breeding tools to move good resistance to both races of the anthracnose fungus into lentil varieties will have major economic benefit to lentil producers and substantially reduce production risks.