Apple Contains Receptor-like Genes Homologous to the Cladosporium fulvum Resistance Gene Family of Tomato with a Cluster of Genes Cosegregating with Vf Apple Scab Resistance

Scab caused by the fungal pathogen Venturia inaequalis is the most common disease of cultivated apple (Malus × domestica Borkh.). Monogenic resistance against scab is found in some small-fruited wild Malus species and has been used in apple breeding for scab resistance. Vf resistance of Malus floribunda 821 is the most widely used scab resistance source. Because breeding a high-quality cultivar in perennial fruit trees takes dozens of years, cloning disease resistance genes and using them in the transformation of high-quality apple varieties would be advantageous. We report the identification of a cluster of receptor-like genes with homology to the Cladosporium fulvum (Cf) resistance gene family of tomato on bacterial artificial chromosome clones derived from the Vf scab resistance locus. Three members of the cluster were sequenced completely. Similar to the Cf gene family of tomato, the deduced amino acid sequences coded by these genes contain an extracellular leucine-rich repeat domain and a transmembrane domain. The transcription of three members of the cluster was determined by reverse transcription-polymerase chain reaction to be constitutive, and the transcription and translation start of one member was verified by 5′ rapid amplification of cDNA ends. We discuss the parallels between Cf resistance of tomato and Vf resistance of apple and the possibility that one of the members of the gene cluster is the Vf gene. Cf homologs from other regions of the apple genome also were identified and are likely to present other scab resistance genes.

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Quantitative Trait Loci (QTL) Analysis Reveals Both Broad-Spectrum and Isolate-Specific QTL for Scab Resistance in an Apple Progeny Challenged with Eight Isolates of Venturia inaequalis

Phytopathology ◽

10.1094/phyto.2004.94.4.370 ◽

2004 ◽

Vol 94 (4) ◽

pp. 370-379 ◽

Cited By ~ 122

Author(s):

F. Calenge ◽

A. Faure ◽

M. Goerre ◽

C. Gebhardt ◽

W. E. Van de Weg ◽

...

Keyword(s):

Quantitative Trait Loci ◽

Resistance Gene ◽

Resistance Genes ◽

Quantitative Trait ◽

Venturia Inaequalis ◽

Scab Resistance ◽

Breeding Programs ◽

Apple Breeding ◽

Trait Loci ◽

New Races

The major scab resistance gene Vf, extensively used in apple breeding programs, was recently overcome by the new races 6 and 7 of the fungal pathogen Venturia inaequalis. New, more durable, scab resistance genes are needed in apple breeding programs. F1 progeny derived from the cross between partially resistant apple cv. Discovery and apple hybrid ‘TN10-8’ were inoculated in the greenhouse with eight isolates of V. inaequalis, including isolates able to overcome Vf. One major resistance gene, Vg, and seven quantitative trait loci (QTL) were identified for resistance to these isolates. Three QTL on linkage group (LG)12, LG13, and LG15 were clearly isolate-specific. Another QTL on LG5 was detected with two isolates. Three QTL on LG1, LG2, and LG17 were identified with most isolates tested, but not with every isolate. The QTL on LG2 displayed alleles conferring different specificities. This QTL co-localized with the major scab resistance genes Vr and Vh8, whereas the QTL on LG1 colocalized with Vf. These results contribute to a better understanding of the genetic basis of the V. inaequalis-Malus × domestica interaction.

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The Rvi15 (Vr2) Apple Scab Resistance Locus Contains Three TIR-NBS-LRR Genes

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-23-5-0608 ◽

2010 ◽

Vol 23 (5) ◽

pp. 608-617 ◽

Cited By ~ 26

Author(s):

Paolo Galli ◽

Andrea Patocchi ◽

Giovanni Antonio Lodovico Broggini ◽

Cesare Gessler

Keyword(s):

Venturia Inaequalis ◽

Interleukin 1 ◽

Apple Scab ◽

Scab Resistance ◽

Receptor Protein ◽

Resistance Locus ◽

Fresh Market ◽

High Quality ◽

Bac Clone ◽

Bac Contig

Scab caused by the pathogen Venturia inaequalis is considered the most important fungal disease of cultivated apple (Malus × domestica Borkh.). In all, 16 monogenic resistances against scab have been found in different Malus spp. and some of them are currently used in apple breeding for scab-resistant cultivars. However, the self incompatibility and the long generation time of Malus spp. together with the high standards of fruit quality demanded from the fresh market render the breeding of high-quality cultivars in apple a long and expensive task. Therefore, the cloning of disease resistance genes and the use of the cloned genes for the transformation of high-quality apple cultivars could be an approach to solve these drawbacks. We report the construction of a bacterial artificial chromosome (BAC) contig spanning the Rvi15 (Vr2) apple scab resistance locus using two GMAL 2473 BAC libraries. A single BAC clone of the contig was sufficient to span the resistance locus. The BAC clone was completely sequenced, allowing identification of a sequence of 48.6 kb going from the two closest markers (ARGH17 and 77G20RP) bracketing Rvi15 (Vr2). Analysis of the 48.6-kb sequence revealed the presence of three putative genes characterized by a Toll and mammalian interleukin-1 receptor protein nucleotide-binding site leucine-rich repeat structure. All three genes were found to be transcribed.

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Virulence Characterization of Venturia inaequalis Reference Isolates on the Differential Set of Malus Hosts

Plant Disease ◽

10.1094/pdis-07-14-0708-re ◽

2015 ◽

Vol 99 (3) ◽

pp. 370-375 ◽

Cited By ~ 13

Author(s):

Valérie Caffier ◽

Andrea Patocchi ◽

Pascale Expert ◽

Marie-Noëlle Bellanger ◽

Charles-Eric Durel ◽

...

Keyword(s):

Resistance Gene ◽

Resistance Genes ◽

Venturia Inaequalis ◽

Apple Scab ◽

Scab Resistance ◽

Reference Set ◽

Major Resistance Gene ◽

Differential Hosts ◽

Major Resistance Genes

A set of differential hosts has recently been identified for 17 apple scab resistance genes in an updated system for defining gene-for-gene (GfG) relationships in the Venturia inaequalis-Malus pathosystem. However, a set of reference isolates characterized for their complementary avirulence alleles is not yet available. In this paper, we report on improving the set of differential hosts for h(7) and propose the apple genotype LPG3-29 as carrying the single major resistance gene Rvi7. We characterized a reference set of 23 V. inaequalis isolates on 14 differential apple hosts carrying major resistance genes under controlled conditions. We identified isolates that were virulent on at least one of the following defined resistance gene hosts: h(1), h(2), h(3), h(4), h(5), h(6), h(7), h(8), h(9), h(10), and h(13). Sixteen different virulence patterns were observed. In general, the isolates carried one to three virulences, but some of them were more complex, with up to six virulences. This set of well-characterized isolates will be helpful for the identification of additional apple scab resistance genes in apple germplasm and the characterization of new GfG relationships to help improve our understanding of the host-pathogen interactions in the V. inaequalis-Malus pathosystem.

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Mapping of the apple scab-resistance gene Vb

Genome ◽

10.1139/g06-096 ◽

2006 ◽

Vol 49 (10) ◽

pp. 1238-1245 ◽

Cited By ~ 33

Author(s):

N. Erdin ◽

S. Tartarini ◽

G.A.L. Broggini ◽

F. Gennari ◽

S. Sansavini ◽

...

Keyword(s):

Molecular Markers ◽

Linkage Group ◽

Resistance Gene ◽

Ssr Markers ◽

Resistance Genes ◽

Venturia Inaequalis ◽

Apple Scab ◽

Scab Resistance ◽

Fast Method ◽

A Genome

Apple scab, caused by the fungus Venturia inaequalis , is the major production constraint in temperate zones with humid springs. Normally, its control relies on frequent and regular fungicide applications. Because this control strategy has come under increasing criticism, major efforts are being directed toward the breeding of scab-resistant apple cultivars. Modern apple breeding programs include the use of molecular markers, making it possible to combine several different scab-resistance genes in 1 apple cultivar (pyramiding) and to speed up the breeding process. The apple scab-resistance gene Vb is derived from the Siberian crab apple ‘Hansen’s baccata #2’, and is 1 of the 6 “historical” major apple scab-resistance genes (Vf, Va, Vr, Vbj, Vm, and Vb). Molecular markers have been published for all these genes, except Vr. In testcross experiments conducted in the 1960s, it was reported that Vb segregated independently from 3 other major resistance genes, including Vf. Recently, however, Vb and Vf have both been mapped on linkage group 1, a result that contrasts with the findings from former testcross experiments. In this study, simple sequence repeat (SSR) markers were used to identify the precise position of Vb in a cross of ‘Golden Delicious’ (vbvb) and ‘Hansen’s baccata #2’ (Vbvb). A genome scanning approach, a fast method already used to map apple scab-resistance genes Vr2 and Vm, was used, and the Vb locus was identified on linkage group 12, between the SSR markers Hi02d05 and Hi07f01. This finding confirms the independent segregation of Vb from Vf. With the identification of SSR markers linked to Vb, another major apple scab-resistance gene has become available; breeders can use it to develop durable resistant cultivars with several different resistance genes.

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Map-based cloning of a gene sequence encoding a nucleotide-binding domain and a leucine-rich region at the Cre3 nematode resistance locus of wheat

Genome ◽

10.1139/g97-087 ◽

1997 ◽

Vol 40 (5) ◽

pp. 659-665 ◽

Cited By ~ 87

Author(s):

Evans S. Lagudah ◽

Odile Moullet ◽

Rudi Appels

Keyword(s):

Disease Resistance ◽

Gene Family ◽

Binding Site ◽

Resistance Gene ◽

Resistance Genes ◽

Gene Sequence ◽

Nucleotide Binding ◽

Disease Resistance Gene ◽

Leucine Rich Repeat ◽

Rich Region

The Cre3 gene confers a high level of resistance to the root endoparasitic nematode Heterodera avenae in wheat. A DNA marker cosegregating with H. avenae resistance was used as an entry point for map-based cloning of a disease resistance gene family at the Cre3 locus. Two related gene sequences have been analysed at the Cre3 locus. One, identified as a cDNA clone, encodes a polypeptide with a nucleotide binding site (NBS) and a leucine-rich region; this member of the disease resistance gene family is expressed in roots. A second Cre3 gene sequence, cloned as genomic DNA, appears to be a pseudogene, with a frame shift caused by a deletion event. These two genes, related to members of the cytoplasmic NBS – leucine rich repeat class of plant disease resistance genes were physically mapped to the distal 0.06 fragment of the long arm of wheat chromosome 2D and cosegregated with nematode resistance.Key words: cereal cyst nematode, disease resistance genes, nucleotide-binding site, leucine-rich repeat.

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A Novel Pear Scab (Venturia nashicola) Resistance Gene, Rvn3, from Interspecific Hybrid Pear (Pyrus pyrifolia × P. communis)

Plants ◽

10.3390/plants10122632 ◽

2021 ◽

Vol 10 (12) ◽

pp. 2632

Author(s):

Sewon Oh ◽

Hyeondae Han ◽

Daeil Kim

Keyword(s):

Resistance Gene ◽

Resistance Genes ◽

Interspecific Hybrid ◽

Dominant Gene ◽

Apple Scab ◽

Scab Resistance ◽

Hybrid Population ◽

Pyrus Pyrifolia ◽

Pear Scab ◽

Venturia Nashicola

Asian pear scab is a fungal disease caused by Venturia nashicola. The identification of genes conferring scab resistance could facilitate the breeding of disease-resistant cultivars. Therefore, the present study aimed to identify a scab-resistance gene using an interspecific hybrid population ((Pyrus pyrifolia × P. communis) × P. pyrifolia). Artificial inoculation of V. nashicola was carried out for two years. The segregation ratio (1:1) of resistant to susceptible individuals indicated that resistance to V. nashicola was inherited from P. communis and controlled by a single dominant gene. Based on two years phenotypic data with the Kruskal–Wallis test and interval mapping, 12 common markers were significantly associated with scab resistance. A novel scab resistance gene, Rvn3, was mapped in linkage group 6 of the interspecific hybrid pear, and co-linearity between Rvn3 and one of the apple scab resistance genes, Rvi14, was confirmed. Notably, an insertion in pseudo-chromosome 6 of the interspecific hybrid cultivar showed homology with apple scab resistance genes. Hence, the newly discovered Rvn3 was considered an ortholog of the apple scab resistance gene. Since the mapping population used in the present study is a pseudo-BC1 population, pyramiding of multiple resistance genes to pseudo-BC1 could facilitate the breeding of pear cultivars with durable resistance.

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Linkage mapping of powdery mildew and greenbug resistance genes on recombinant 1RS from 'Amigo' and 'Kavkaz' wheat–rye translocations of chromosome 1RS.1AL

Genome ◽

10.1139/g03-101 ◽

2004 ◽

Vol 47 (2) ◽

pp. 292-298 ◽

Cited By ~ 25

Author(s):

Yehia Mater ◽

Stephen Baenziger ◽

Kulvinder Gill ◽

Robert Graybosch ◽

Lynda Whitcher ◽

...

Keyword(s):

Disease Resistance ◽

Powdery Mildew ◽

Resistance Gene ◽

Resistance Genes ◽

Dna Sequences ◽

Secale Cereale ◽

Polyacrylamide Gel Electrophoresis ◽

Rflp Markers ◽

Resistance Locus ◽

Greenbug Resistance

Cultivated rye (Secale cereale L., 2n = 2x = 14, RR) is an important source of genes for insect and disease resistance in wheat (Triticum aestivum L., 2n = 6x = 42). Rye chromosome arm 1RS of S. cereale 'Kavkaz' originally found as a 1BL.1RS translocation, carries genes for disease resistance (e.g., Lr26, Sr31, Yr9, and Pm8), while 1RS of the S. cereale 'Amigo' translocation (1RSA) carries a single resistance gene for greenbug (Schizaphis graminum Rondani) biotypes B and C and also carries additional disease-resistance genes. The purpose of this research was to identify individual plants that were recombinant in the homologous region of.1AL.1RSV and 1AL.1RSA using both molecular and phenotypic markers. Secale cereale 'Nekota' (1AL.1RSA) and S. cereale 'Pavon 76' (1AL.1RSV) were mated and the F1 was backcrossed to 'Nekota' (1AL.1AS) to generate eighty BC1F2:3 families (i.e., ('Nekota' 1AL.1RSA × 'Pavon 76' 1AL.1RSV) × 'Nekota' 1AL.1AS). These families were genotyped using the secalin–gliadin grain storage protein banding pattern generated with polyacrylamide gel electrophoresis to discriminate 1AL.1AS/1AL.1RS heterozygotes from the 1AL.1RSA+V and 1AL.1AS homozygotes. Segregation of the secalin locus and PCR markers based on the R173 family of rye specific repeated DNA sequences demonstrated the presence of recombinant 1AL.1RSA+V families. Powdery mildew (Blumeria graminis) and greenbug resistance genes on the recombinant 1RSA+V arm were mapped in relation to the Sec-1 locus, 2 additional protein bands, 3 SSRs, and 13 RFLP markers. The resultant linkage map of 1RS spanned 82.4 cM with marker order and spacing showing reasonable agreement with previous maps of 1RS. Fifteen markers lie within a region of 29.7 cM next to the centromere, yet corresponded to just 36% of the overall map length. The map position of the RFLP marker probe mwg68 was 10.9 cM distal to the Sec-1 locus and 7.8 cM proximal to the powdery mildew resistance locus. The greenbug resistance gene was located 2.7 cM proximal to the Sec-1 locus.Key words: microsatellites, SSRs, RFLP, secalin-gliadin, alien genes introgression.

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Genomic Organization and Comparative Phylogenic Analysis of NBS-LRR Resistance Gene Family in Solanum pimpinellifolium and Arabidopsis thaliana

Evolutionary Bioinformatics ◽

10.1177/1176934320911055 ◽

2020 ◽

Vol 16 ◽

pp. 117693432091105

Author(s):

Huawei Wei ◽

Jia Liu ◽

Qinwei Guo ◽

Luzhao Pan ◽

Songlin Chai ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Phylogenetic Analysis ◽

Gene Family ◽

Resistance Gene ◽

Resistance Genes ◽

Chromosome Mapping ◽

Gene Families ◽

Gene Clusters ◽

Motif Analysis ◽

Solanum Pimpinellifolium

NBS-LRR (nucleotide-binding site and leucine-rich repeat) is one of the largest resistance gene families in plants. The completion of the genome sequencing of wild tomato Solanum pimpinellifolium provided an opportunity to conduct a comprehensive analysis of the NBS-LRR gene superfamily at the genome-wide level. In this study, gene identification, chromosome mapping, and phylogenetic analysis of the NBS-LRR gene family were analyzed using the bioinformatics methods. The results revealed 245 NBS-LRRs in total, similar to that in the cultivated tomato. These genes are unevenly distributed on 12 chromosomes, and ~59.6% of them form gene clusters, most of which are tandem duplications. Phylogenetic analysis divided the NBS-LRRs into 2 subfamilies (CNL-coiled-coil NBS-LRR and TNL-TIR NBS-LRR), and the expansion of the CNL subfamily was more extensive than the TNL subfamily. Novel conserved structures were identified through conserved motif analysis between the CNL and TNL subfamilies. Compared with the NBS-LRR sequences from the model plant Arabidopsis thaliana, wide genetic variation occurred after the divergence of S. pimpinellifolium and A thaliana. Species-specific expansion was also found in the CNL subfamily in S. pimpinellifolium. The results of this study provide the basis for the deeper analysis of NBS-LRR resistance genes and contribute to mapping and isolation of candidate resistance genes in S. pimpinellifolium.

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RMo1 Confers Blast Resistance in Barley and Is Located within the Complex of Resistance Genes Containing Mla, a Powdery Mildew Resistance Gene

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-19-1034 ◽

2006 ◽

Vol 19 (9) ◽

pp. 1034-1041 ◽

Cited By ~ 21

Author(s):

Tsuyoshi Inukai ◽

M. Isabel Vales ◽

Kiyosumi Hori ◽

Kazuhiro Sato ◽

Patrick M. Hayes

Keyword(s):

Powdery Mildew ◽

Linkage Map ◽

Resistance Gene ◽

Resistance Genes ◽

Rice Blast ◽

Powdery Mildew Resistance ◽

Blast Disease ◽

Grass Species ◽

Resistance Locus ◽

Mildew Resistance

Isolates of Magnaporthe oryzae (the causal agent of rice blast disease) can infect a range of grass species, including barley. We report that barley Hordeum vulgare cv. Baronesse and an experimental line, BCD47, show a range of resistance reactions to infection with two rice blast isolates. The complete resistance of Baronesse to the isolate Ken 54–20 is controlled by a single dominant gene, designated RMo1. RMo1 mapped to the same linkage map position on chromosome 1H as the powdery mildew resistance locus Mla and an expressed sequence tag (k04320) that corresponds to the barley gene 711N16.16. A resistance quantitative trait locus (QTL), at which Baronesse contributed the resistance allele, to the isolate Ken 53–33 also mapped at the same position as RMo1. Synteny analysis revealed that a corresponding region on rice chromosome 5 includes the bacterial blight resistance gene xa5. These results indicate that a defined region on the short arm of barley chromosome 1H, including RMo1 and Mla, harbors genes conferring qualitative and quantitative resistance to multiple pathogens. The partial resistance of BCD47 to Ken53–33 is determined by alleles at three QTL, two of which coincide with the linkage map positions of the mildew resistance genes mlo and Mlf.

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Molecular screening of domestic apple cultivars for scab resistance genes in Greece

Czech Journal of Genetics and Plant Breeding ◽

10.17221/119/2019-cjgpb ◽

2020 ◽

Vol 56 (No. 4) ◽

pp. 165-169

Author(s):

Lefkothea Karapetsi ◽

Irini Nianiou-Obeidat ◽

Antonios Zambounis ◽

Maslin Osathanunkul ◽

Panagiotis Madesis

Keyword(s):

Resistance Genes ◽

Venturia Inaequalis ◽

Apple Scab ◽

Scab Resistance ◽

Molecular Screening ◽

Polygenic Resistance ◽

Main Target ◽

Efficient Control ◽

Apple Cultivars ◽

Efficient Breeding

Apple scab caused by Venturia inaequalis has the most destructive effects among other phytopathogens in apple crops all over the world. The integration of resistance genes from local and domestic cultivars is a prerequisite for the efficient control of this disease and is a main target in efficient breeding approaches. Across Greece, many domestic apple cultivars are reported without deep knowledge about the presence and diversity of scab resistance genes. In this study, the presence of five resistance genes (Rvi2, Rvi4, Rvi6, Rvi8 and Rvi11) was evaluated across twenty local and domestic apple genotypes, employing twelve molecular markers closely linked to known apple scab resistance loci. Significant differences and polymorphisms among the tested cultivars were detected suggesting that some of them carry a sufficient number of resistance genes. This observed genetic diversity could be exploited in ongoing breeding approaches as a natural source of polygenic resistance against apple scab.

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