Comparative Reaction of Camelina sativa to Sclerotinia sclerotiorum and Leptosphaeria maculans

• Published in: Plant disease p. PDIS03190664RE
• Main Authors: Purnamasari, Maria I, Erskine, William, Croser, Janine S, You, Ming Pei, Barbetti, Martin J
• Format: Journal Article
• Language: English
• Published: United States 01.11.2019
• Subjects: disease resistance; resistance heritability
• ISSN: 0191-2917
• DOI: 10.1094/PDIS-03-19-0664-RE

and are two of the most important pathogens of many cruciferous crops. The reaction of 30 genotypes of (false flax) was determined against both pathogens. genotypes were inoculated at seedling and adult stages with two pathotypes of , highly virulent MBRS-1 and less virulent WW-1. There were significant differences ( < 0.001) among genotypes, between pathotypes, and a significant interaction between genotypes and pathotypes in relation to percent cotyledon disease index (% CDI) and stem lesion length. Genotypes 370 (% CDI 20.5, stem lesion length 1.8 cm) and 253 (% CDI 24.8, stem lesion length 1.4 cm) not only consistently exhibited cotyledon and stem resistance, in contrast to susceptible genotype 2305 (% CDI 37.7, stem lesion length 7.2 cm), but their resistance was independent to pathotype. A F -recombinant inbred line population was developed from genotypes 370 × 2305 and responses characterized. Low broad-sense heritability indicated a complex pattern of inheritance of resistance to . Six isolates of , covering combinations of five different avirulent loci (i.e., five different races), were tested on cotyledons across two experiments. There was a high level of resistance, with % CDI < 17, and including development of a hypersensitive reaction. This is the first report of variable reaction of to different races of and the first demonstrating comparative reactions of to and This study not only provides new understanding of these comparative resistances in , but highlights their potential as new sources of resistance, both for crucifer disease-resistance breeding in general and to enable broader adoption of as a more sustainable oilseed crop in its own right.