Genetic Control of Interspecific‐Derived and Juvenile Resistance in Lentil to Colletotrichum truncatum

Abstract

Anthracnose, caused by Colletotrichum truncatum (Ct), is a major disease of lentil (Lens culinaris ssp. culinaris Medik.; Lcc) on the Canadian prairies. Resistance to the more virulent race CtO of the pathogen is extremely rare within the Lcc gene pool; partial resistance to race CtO in Lcc breaks down as the plant progresses through the adult phase (AP). Resistance was introgressed from Lens ervoides (Le) and the F., and Fg generations of two introgression populations assessed for resistance when inoculated separately with both races of Cf. One population was tested with race CtO at both the juvenile phase (JP) and AP. F2.3 families were also tested for race CtO resistance. Resistance from Le to both races of Of appears to be due to the same gene(s) or tightly linked genes. Different models for genetic control of resistance between populations are observed depending on whether the interspecific line is crossed into a susceptible or partially resistant Lcc background; however, duplicate recessive epistasis seems to control susceptibility in the susceptible background and when juvenile resistance is not a factor. Significant differences between phases were evident for more than a third of the FjS tested, supporting different resistance gene action based on growth phase; resistarKje in the JP seemed to be due to dominant and recessive epistasis. Results suggest genetiq control of juvenile resistance in combination with interspecific-derived resistance is complex.

A Novel Lens orientalis Resistance Source to the Recently Evolved Highly Aggressive Australian Ascochyta lentis Isolates

“…Subsequently, segregating populations for ascochyta resistance were successfully produced from L. culinaris × L. orientalis and L. culinaris × L. ervoides crosses, within which resistance was simply inherited (Ahmad et al, 1997). More recently, Fiala et al (2009) successfully transferred anthracnose resistance from L. ervoides to L. culinaris and developed RIL population which was later evaluated by Vail (2010). This cross was also used to generate backcrosses which were reported to be stable and without any phenotypic linkage drag with yield.…”

Comparative Agronomic Performance and Reaction to Fusarium wilt of Lens culinaris × L. orientalis and L. culinaris × L. ervoides derivatives

“…Furthermore, the common better performing F 5 recombinant lines selected from Delhi and Shimla centers reveals their wider adaptation and potential for developing high yielding cultivars of lentil and these lines can also be utilized as donors for further cross- breeding purposes in lentil genetic improvement (Singh et al, 2013; Tullu et al, 2013). The review of literature pertinent on widening the genetic base of cultivated lentil in relation to transferring resistance from wild Lens species against anthracnose (Fiala, 2006; Tullu et al, 2006; Fiala et al, 2009; Vail and Vandenberg, 2011; Vail et al, 2012), ascochyta blight (Tullu et al, 2010), Stemphylium blight (Podder et al, 2013) and yield attributes (Gupta and Sharma, 2006, 2007; Singh et al, 2013) have been successfully attempted. The current research results are in the line of other successes to transferring resistance against Fusarium wilt including yield related traits from the species L. ervoides and subspecies L. culinaris subsp.…”

New sources of resistance to Colletotrichum truncatum race Ct0 and Ct1 in Lens culinaris Medikus subsp. culinaris obtained by single plant selection in germplasm accessions

“…Nevertheless, a single resistant line was selected from the above study by Fiala et al (2009) for crossing with cultivar 'CDC Redberry' resistant to race Ct1 and 'Eston' susceptible to both races. The resulting segregating ratios of progenies were unclear and further confounded by an effect of plant growth stage at the time of inoculation (Vail and Vandenberg 2011). Both studies illustrated the difficulties with transfer of resistance genes from outside the primary gene pool, which by definition is associated with crossing barriers and linkage drag as also seen in other crop species (Foolad et al 2005).…”