Different Alleles of a Gene Encoding Leucoanthocyanidin Reductase (PaLAR3) Influence Resistance against the Fungus Heterobasidion parviporum in Picea abies
2016 (English)In: Plant Physiology, ISSN 0032-0889, E-ISSN 1532-2548, Vol. 171, no 4, 2671-2681 p.Article in journal (Refereed) Published
Despite the fact that fungal diseases are a growing menace for conifers in modern silviculture, only a very limited number of molecular markers for pathogen resistance have been validated in conifer species. A previous genetic study indicated that the resistance of Norway spruce (Picea abies) to Heterobasidion annosum s.l., a pathogenic basidiomycete species complex, is linked to a quantitative trait loci that associates with differences in fungal growth in sapwood (FGS) that includes a gene, PaLAR3, which encodes a leucoanthocyanidin reductase. In this study, gene sequences showed the presence of two PaLAR3 allelic lineages in P. abies. Higher resistance was associated with the novel allele, which was found in low frequency in the four P. abies populations that we studied. Norway spruce plants carrying at least one copy of the novel allele showed a significant reduction in FGS after inoculation with Heterobasidion parviporum compared to their half-siblings carrying no copies, indicating dominance of this allele. The amount of (+) catechin, the enzymatic product of PaLAR3, was significantly higher in bark of trees homozygous for the novel allele. Although we observed that the in vitro activities of the enzymes encoded by the two alleles were similar, we could show that allele-specific transcript levels were significantly higher for the novel allele, indicating that regulation of gene expression is responsible for the observed effects in resistance, possibly caused by differences in cis-acting elements that we observe in the promoter region of the two alleles.
Place, publisher, year, edition, pages
2016. Vol. 171, no 4, 2671-2681 p.
IdentifiersURN: urn:nbn:se:uu:diva-303295DOI: 10.1104/pp.16.00685ISI: 000381303700031PubMedID: 27317690OAI: oai:DiVA.org:uu-303295DiVA: diva2:971276
FunderSwedish Foundation for Strategic Research , R8b08-0011Swedish Research Council Formas, 2012-1276 217-2007-433EU, European Research CouncilEU, FP7, Seventh Framework Programme, 211868