78 research outputs found
A genome-wide identification and comparative analysis of the lentil MLO genes
Revista electrónica on linePowdery mildew is a widespread fungal plant disease that can cause significant losses in
many crops. Some MLO genes (Mildew resistance locus O) have proved to confer a durable
resistance to powdery mildew in several species. Resistance granted by the MLO gene family
members has prompted an increasing interest in characterizing these genes and implementing
their use in plant breeding. Lentil (Lens culinaris Medik.) is a widely grown food
legume almost exclusively consumed as dry seed with an average world production of 4.5
million tons. Powdery mildew causes severe losses on certain lentil cultivars under particular
environmental conditions. Data mining of the lentil CDC Redberry draft genome allowed to
identify up to 15 gene sequences with homology to known MLO genes, designated as
LcMLOs. Further characterization of these gene sequences and their deduced protein
sequences demonstrated conformity with key MLO protein characteristics such as the presence
of transmembrane and calmodulin binding domains, as well as that of other conserved
motifs. Phylogenetic and other comparative analyses revealed that LcMLO1 and LcMLO3
are the most likely gene orthologs related to powdery mildew response in other species,
sharing a high similarity with other known resistance genes of dicot species, such as pea
PsMLO1 and Medicago truncatula MtMLO1 and MtMLO3. Sets of primers were designed
as tools to PCR amplify the genomic sequences of LcMLO1 and LcMLO3, also to screen
lentil germplasm in search of resistance mutants. Primers were used to obtain the complete
sequences of these two genes in all of the six wild lentil relatives. Respective to each gene,
all Lens sequences shared a high similarity. Likewise, we used these primers to screen a
working collection of 58 cultivated and 23 wild lentil accessions in search of length polymorphisms
present in these two genes. All these data widen the insights on this gene family and
can be useful for breeding programs in lentil and close related species.S
ZED1-related kinase 13 is required for resistance against Pseudoidium neolycopersici in Arabidopsis accession Bla-6
To explore specific components of resistance against the tomato-adapted powdery mildew pathogen Pseudoidium neolycopersici (On) in the model plant Arabidopsis, we performed a disease assay in 123 accessions. When testing the resistance in the F1 from crossings between resistant accessions with susceptible Col-0 or Sha, only the progeny of the cross between accession Bla-6 and Col-0 displayed a completely resistant phenotype. The resistance in Bla-6 is known to be specific for Pseudoidium neolycopersici. QTL analysis and fine-mapping through several rounds of recombinant screenings allowed us to locate a major resistance QTL in an interval on chromosome 1, containing two candidate genes and an intergenic insertion. Via CRISPR/Cas9 targeted mutagenesis, we could show that knocking out the ZED-1 RELATED KINASE 13 (ZRK13) gene compromised the On resistance in Bla-6. Several polymorphisms are observed in the ZRK13 allelic variant of Bla-6 when compared to the Col-0 protein
- …