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Brouwer SM, Lindqvist-Reis P, Persson DP, Marttila S, Grenville-Briggs LJ, Andreasson E. Visualising the ionome in resistant and susceptible plant-pathogen interactions. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 108:870-885. [PMID: 34407245 DOI: 10.1111/tpj.15469] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 07/29/2021] [Accepted: 08/09/2021] [Indexed: 06/13/2023]
Abstract
At the morphological and anatomical levels, the ionome, or the elemental composition of an organism, is an understudied area of plant biology. In particular, the ionomic responses of plant-pathogen interactions are scarcely described, and there are no studies on immune reactions. In this study we explored two X-ray fluorescence (XRF)-based ionome visualisation methods (benchtop- and synchrotron-based micro-XRF [µXRF]), as well as the quantitative inductively coupled plasma optical emission spectroscopy (ICP-OES) method, to investigate the changes that occur in the ionome of compatible and incompatible plant-pathogen interactions. We utilised the agronomically important and comprehensively studied interaction between potato (Solanum tuberosum) and the late blight oomycete pathogen Phytophthora infestans as an example. We used one late blight-susceptible potato cultivar and two resistant transgenic plant lines (only differing from the susceptible cultivar in one or three resistance genes) both in control and P. infestans-inoculated conditions. In the lesions from the compatible interaction, we observed rearrangements of several elements, including a decrease of the mobile macronutrient potassium (K) and an increase in iron (Fe) and manganese (Mn), compared with the tissue outside the lesion. Interestingly, we observed distinctly different distribution patterns of accumulation at the site of inoculation in the resistant lines for calcium (Ca), magnesium (Mg), Mn and silicon (Si) compared to the susceptible cultivar. The results reveal different ionomes in diseased plants compared to resistant plants. Our results demonstrate a technical advance and pave the way for deeper studies of the plant-pathogen ionome in the future.
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Affiliation(s)
- Sophie M Brouwer
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Patric Lindqvist-Reis
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
- Institute for Nuclear Waste Disposal, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Daniel P Persson
- Department of Plant and environmental Sciences (PLEN), University of Copenhagen, Kobenhavn, Denmark
| | - Salla Marttila
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Laura J Grenville-Briggs
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Erik Andreasson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
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2
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Kieu NP, Lenman M, Wang ES, Petersen BL, Andreasson E. Mutations introduced in susceptibility genes through CRISPR/Cas9 genome editing confer increased late blight resistance in potatoes. Sci Rep 2021; 11:4487. [PMID: 33627728 PMCID: PMC7904907 DOI: 10.1038/s41598-021-83972-w] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 02/10/2021] [Indexed: 01/31/2023] Open
Abstract
The use of pathogen-resistant cultivars is expected to increase yield and decrease fungicide use in agriculture. However, in potato breeding, increased resistance obtained via resistance genes (R-genes) is hampered because R-gene(s) are often specific for a pathogen race and can be quickly overcome by the evolution of the pathogen. In parallel, susceptibility genes (S-genes) are important for pathogenesis, and loss of S-gene function confers increased resistance in several plants, such as rice, wheat, citrus and tomatoes. In this article, we present the mutation and screening of seven putative S-genes in potatoes, including two DMR6 potato homologues. Using a CRISPR/Cas9 system, which conferred co-expression of two guide RNAs, tetra-allelic deletion mutants were generated and resistance against late blight was assayed in the plants. Functional knockouts of StDND1, StCHL1, and DMG400000582 (StDMR6-1) generated potatoes with increased resistance against late blight. Plants mutated in StDND1 showed pleiotropic effects, whereas StDMR6-1 and StCHL1 mutated plants did not exhibit any growth phenotype, making them good candidates for further agricultural studies. Additionally, we showed that DMG401026923 (here denoted StDMR6-2) knockout mutants did not demonstrate any increased late blight resistance, but exhibited a growth phenotype, indicating that StDMR6-1 and StDMR6-2 have different functions. To the best of our knowledge, this is the first report on the mutation and screening of putative S-genes in potatoes, including two DMR6 potato homologues.
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Affiliation(s)
- Nam Phuong Kieu
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Marit Lenman
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Eu Sheng Wang
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Bent Larsen Petersen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsen's vej 40, 1871, Frederiksberg C, Denmark
| | - Erik Andreasson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
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3
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Wang ES, Kieu NP, Lenman M, Andreasson E. Tissue Culture and Refreshment Techniques for Improvement of Transformation in Local Tetraploid and Diploid Potato with Late Blight Resistance as an Example. PLANTS (BASEL, SWITZERLAND) 2020; 9:E695. [PMID: 32486039 PMCID: PMC7356882 DOI: 10.3390/plants9060695] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 12/29/2022]
Abstract
Potato (Solanum tuberosum) is among the best producers of edible biomass in terms of yield per hectare and a variety of different regional cultivars are used as a staple commodity in many countries. However, this crop is attacked by several diseases, with the worst being the late blight disease caused by Phytophthora infestans. Stacking of resistance (R) genes from wild Solanum relatives are interesting prospects for the sustainable control of late blight. Therefore, we optimized methods for the efficient generation and screening of R-gene-containing transformants in tetraploid and diploid hybrid potato genotypes. Using these methods, a high transformation efficiency was achieved for the transformation of tetraploid and diploid potato lines with a triple resistance (3R) gene construct. Transformation efficiencies were improved by optimizing several factors affecting regeneration, including the quality of the starting plant material, and the composition of the plant growth regulators used during selective regeneration. A refreshment protocol was designed to alleviate in vitro related stress in stock plants, which significantly improved the growth vigor and resulted in a 4- to 10-fold increase in transformation efficiency. Furthermore, long-term exposure to exogenous Indole-3-butyric acid that is usually used for the initiation of roots in vitro, was found to cause aberrant morphological phenotypes in potato.
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Noman A, Aqeel M, Qasim M, Haider I, Lou Y. Plant-insect-microbe interaction: A love triangle between enemies in ecosystem. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 699:134181. [PMID: 31520944 DOI: 10.1016/j.scitotenv.2019.134181] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/28/2019] [Accepted: 08/28/2019] [Indexed: 05/20/2023]
Abstract
In natural ecosystems, plants interact with biotic components such as microbes, insects, animals and other plants as well. Generally, researchers have focused on each interaction separately, which condenses the significance of the interaction. This limited presentation of the facts masks the collective role of constantly interacting organisms in complex communities disturbing not only plant responses but also the response of organisms for each other in natural ecological settings. Beneficial microorganisms interact with insect herbivores, their predators and pollinators in a bidirectional way through the plant. Fascinatingly, insects employ diverse tactics to protect themselves from parasites or predators. Influences of microbial and insects attack on plants can bring changes in info-chemical frameworks and play a role in the food chain also. After insect herbivory and microbial pathogenesis, plants exhibit intense morpho-physiological and chemical reprogramming that leads to repellence/attraction of attacking organism or its natural enemy. The characterization of such interactions in different ecosystems is receiving due consideration, and underlying molecular and physiological mechanisms must be the point of concentration to unveil the evolution of multifaceted multitrophic interactions. Therefore, we have focused this phenomenon in a more realistic setting by integrating ecology and physiology to portray these multidimensional interfaces. We have shown, in this article, physiological trajectories in plant-microbe and insect relationship and their ecological relevance in nature. We focus and discuss microbial pathogenesis in plants, induced defense and the corresponding behavior of herbivore insects and vice-versa. It is hoped that this review will stimulate interest and zeal in microbes mediated plant-insect interactions along with their ecological consequences and encourage scientists to accept the challenges in this field.
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Affiliation(s)
- Ali Noman
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China; Department of Botany, Government College University, Faisalabad 38040, Pakistan.
| | - Muhammad Aqeel
- State Key Laboratory of Grassland Agro-ecosystems, School of Life Sciences, Lanzhou University, Lanzhou 730000, Gansu, PR China
| | - Muhammad Qasim
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China
| | - Ijaz Haider
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China; Department of Entomology, University of Agriculture, Faisalabad 38040, Pakistan
| | - Yonggen Lou
- Institute of Insect Sciences, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310058, PR China.
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Proteomics of PTI and Two ETI Immune Reactions in Potato Leaves. Int J Mol Sci 2019; 20:ijms20194726. [PMID: 31554174 PMCID: PMC6802228 DOI: 10.3390/ijms20194726] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 09/16/2019] [Accepted: 09/22/2019] [Indexed: 12/29/2022] Open
Abstract
Plants have a variety of ways to defend themselves against pathogens. A commonly used model of the plant immune system is divided into a general response triggered by pathogen-associated molecular patterns (PAMPs), and a specific response triggered by effectors. The first type of response is known as PAMP triggered immunity (PTI), and the second is known as effector-triggered immunity (ETI). To obtain better insight into changes of protein abundance in immunity reactions, we performed a comparative proteomic analysis of a PTI and two different ETI models (relating to Phytophthora infestans) in potato. Several proteins showed higher abundance in all immune reactions, such as a protein annotated as sterol carrier protein 2 that could be interesting since Phytophthora species are sterol auxotrophs. RNA binding proteins also showed altered abundance in the different immune reactions. Furthermore, we identified some PTI-specific changes of protein abundance, such as for example, a glyoxysomal fatty acid beta-oxidation multifunctional protein and a MAR-binding protein. Interestingly, a lysine histone demethylase was decreased in PTI, and that prompted us to also analyze protein methylation in our datasets. The proteins upregulated explicitly in ETI included several catalases. Few proteins were regulated in only one of the ETI interactions. For example, histones were only downregulated in the ETI-Avr2 interaction, and a putative multiprotein bridging factor was only upregulated in the ETI-IpiO interaction. One example of a methylated protein that increased in the ETI interactions was a serine hydroxymethyltransferase.
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Masini L, Grenville‐Briggs LJ, Andreasson E, Råberg L, Lankinen Å. Tolerance and overcompensation to infection by Phytophthora infestans in the wild perennial climber Solanum dulcamara. Ecol Evol 2019; 9:4557-4567. [PMID: 31031927 PMCID: PMC6476776 DOI: 10.1002/ece3.5057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/16/2019] [Accepted: 02/21/2019] [Indexed: 12/12/2022] Open
Abstract
Studies of infection by Phytophthora infestans-the causal agent of potato late blight-in wild species can provide novel insights into plant defense responses, and indicate how wild plants might be influenced by recurrent epidemics in agricultural fields. In the present study, our aim was to investigate if different clones of Solanum dulcamara (a relative of potato) collected in the wild differ in resistance and tolerance to infection by a common European isolate of P. infestans. We performed infection experiments with six S. dulcamara genotypes (clones) both in the laboratory and in the field and measured the degree of infection and plant performance traits. In the laboratory, the six evaluated genotypes varied from resistant to susceptible, as measured by degree of infection 20 days post infection. Two of the four genotypes susceptible to infection showed a quadratic (concave downward) relationship between the degree of infection and shoot length, with maximum shoot length at intermediate values of infection. This result suggests overcompensation, that is, an increase in growth in infected individuals. The number of leaves decreased with increasing degree of infection, but at different rates in the four susceptible genotypes, indicating genetic variation for tolerance. In the field, the inoculated genotypes did not show any disease symptoms, but plant biomass at the end of the growing season was higher for inoculated plants than for controls, in-line with the overcompensation detected in the laboratory. We conclude that in S. dulcamara there are indications of genetic variation for both resistance and tolerance to P. infestans infection. Moreover, some genotypes displayed overcompensation. Learning about plant tolerance and overcompensation to infection by pathogens can help broaden our understanding of plant defense in natural populations and help develop more sustainable plant protection strategies for economically important crop diseases.
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Affiliation(s)
- Laura Masini
- Plant Protection BiologySwedish University of Agricultural SciencesAlnarpSweden
- Present address:
British American TobaccoPlant Biotechnology DivisionCambridgeUK
| | | | - Erik Andreasson
- Plant Protection BiologySwedish University of Agricultural SciencesAlnarpSweden
| | - Lars Råberg
- Department of BiologyLund UniversityLundSweden
| | - Åsa Lankinen
- Plant Protection BiologySwedish University of Agricultural SciencesAlnarpSweden
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Burra DD, Lenman M, Levander F, Resjö S, Andreasson E. Comparative Membrane-Associated Proteomics of Three Different Immune Reactions in Potato. Int J Mol Sci 2018; 19:ijms19020538. [PMID: 29439444 PMCID: PMC5855760 DOI: 10.3390/ijms19020538] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 02/02/2018] [Accepted: 02/08/2018] [Indexed: 11/16/2022] Open
Abstract
Plants have evolved different types of immune reactions but large-scale proteomics about these processes are lacking, especially in the case of agriculturally important crop pathosystems. We have established a system for investigating PAMP-triggered immunity (PTI) and two different effector-triggered immunity (ETI; triggered by Avr2 or IpiO) responses in potato. The ETI responses are triggered by molecules from the agriculturally important Phytophthora infestans interaction. To perform large-scale membrane protein-based comparison of these responses, we established a method to extract proteins from subcellular compartments in leaves. In the membrane fractions that were subjected to quantitative proteomics analysis, we found that most proteins regulated during PTI were also regulated in the same way in ETI. Proteins related to photosynthesis had lower abundance, while proteins related to oxidative and biotic stress, as well as those related to general antimicrobial defense and cell wall degradation, were found to be higher in abundance. On the other hand, we identified a few proteins—for instance, an ABC transporter-like protein—that were only found in the PTI reaction. Furthermore, we also identified proteins that were regulated only in ETI interactions. These included proteins related to GTP binding and heterotrimeric G-protein signaling, as well as those related to phospholipase signaling.
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Affiliation(s)
- Dharani Dhar Burra
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
| | - Marit Lenman
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
| | - Fredrik Levander
- Department of Immunotechnology, Lund University, 221 00 Lund, Sweden.
| | - Svante Resjö
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
| | - Erik Andreasson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, 230 53 Alnarp, Sweden.
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8
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Alexandersson E, Mulugeta T, Lankinen Å, Liljeroth E, Andreasson E. Plant Resistance Inducers against Pathogens in Solanaceae Species-From Molecular Mechanisms to Field Application. Int J Mol Sci 2016; 17:E1673. [PMID: 27706100 PMCID: PMC5085706 DOI: 10.3390/ijms17101673] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 09/16/2016] [Accepted: 09/21/2016] [Indexed: 12/17/2022] Open
Abstract
This review provides a current summary of plant resistance inducers (PRIs) that have been successfully used in the Solanaceae plant family to protect against pathogens by activating the plant's own defence. Solanaceous species include many important crops such as potato and tomato. We also present findings regarding the molecular processes after application of PRIs, even if the number of such studies still remains limited in this plant family. In general, there is a lack of patterns regarding the efficiency of induced resistance (IR) both between and within solanaceous species. In many cases, a hypersensitivity-like reaction needs to form in order for the PRI to be efficient. "-Omics" studies have already given insight in the complexity of responses, and can explain some of the differences seen in efficacy of PRIs between and within species as well as towards different pathogens. Finally, examples of field applications of PRIs for solanaceous crops are presented and discussed. We predict that PRIs will play a role in future plant protection strategies in Solanaceae crops if they are combined with other means of disease control in different spatial and temporal combinations.
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Affiliation(s)
- Erik Alexandersson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden.
| | - Tewodros Mulugeta
- Department of Zoological Science, Addis Ababa University, 1176 Addis Ababa, Ethiopia.
| | - Åsa Lankinen
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden.
| | - Erland Liljeroth
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden.
| | - Erik Andreasson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, P.O. Box 102, 23053 Alnarp, Sweden.
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Lankinen Å, Abreha KB, Alexandersson E, Andersson S, Andreasson E. Nongenetic Inheritance of Induced Resistance in a Wild Annual Plant. PHYTOPATHOLOGY 2016; 106:877-83. [PMID: 27070426 DOI: 10.1094/phyto-10-15-0278-r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Nongenetic inheritance (e.g., transgenerational epigenetic effects) has received increasing interest in recent years, particularly in plants. However, most studies have involved a few model species and relatively little is known about wild species in these respects. We investigated transgenerational induced resistance to infection by the devastating oomycete Phytophthora infestans in Solanum physalifolium, a wild relative of cultivated potato. We treated plants with β-aminobutyric acid (BABA), a nontoxic compound acting as an inducing agent, or infected plants with P. infestans. BABA treatment reduced lesion size in detached-leaf assays inoculated by P. infestans in two of three tested genotypes, suggesting that resistance to oomycetes can be induced by BABA within a generation not only in crops or model species but also in wild species directly collected from nature. Both BABA treatment and infection in the parental generation reduced lesions in the subsequent generation in one of two genotypes, indicating a transgenerational influence on resistance that varies among genotypes. We did not detect treatment effects on seed traits, indicating the involvement of a mechanism unrelated to maternal effects. In conclusion, our study provides data on BABA induction and nongenetic inheritance of induced resistance in a wild relative of cultivated potato, implying that this factor might be important in the ecological and agricultural landscape.
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Affiliation(s)
- Åsa Lankinen
- First, second, third, and fifth authors: Swedish University of Agricultural Sciences, Plant Protection Biology, P.O. Box 102, S-230 53 Alnarp, Sweden; and fourth author: Department of Biology, Lund University, Ecology Building, S-223 62 Lund, Sweden
| | - Kibrom B Abreha
- First, second, third, and fifth authors: Swedish University of Agricultural Sciences, Plant Protection Biology, P.O. Box 102, S-230 53 Alnarp, Sweden; and fourth author: Department of Biology, Lund University, Ecology Building, S-223 62 Lund, Sweden
| | - Erik Alexandersson
- First, second, third, and fifth authors: Swedish University of Agricultural Sciences, Plant Protection Biology, P.O. Box 102, S-230 53 Alnarp, Sweden; and fourth author: Department of Biology, Lund University, Ecology Building, S-223 62 Lund, Sweden
| | - Stefan Andersson
- First, second, third, and fifth authors: Swedish University of Agricultural Sciences, Plant Protection Biology, P.O. Box 102, S-230 53 Alnarp, Sweden; and fourth author: Department of Biology, Lund University, Ecology Building, S-223 62 Lund, Sweden
| | - Erik Andreasson
- First, second, third, and fifth authors: Swedish University of Agricultural Sciences, Plant Protection Biology, P.O. Box 102, S-230 53 Alnarp, Sweden; and fourth author: Department of Biology, Lund University, Ecology Building, S-223 62 Lund, Sweden
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10
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Lenman M, Ali A, Mühlenbock P, Carlson-Nilsson U, Liljeroth E, Champouret N, Vleeshouwers VGAA, Andreasson E. Effector-driven marker development and cloning of resistance genes against Phytophthora infestans in potato breeding clone SW93-1015. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2016; 129:105-15. [PMID: 26518573 DOI: 10.1007/s00122-015-2613-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 09/29/2015] [Indexed: 05/03/2023]
Abstract
We show the usefulness of integrating effector screening in a breeding program and in resistance gene cloning, with Phytophthora resistance in the Swedish potato breeding clone SW93-1015 as an example. Phytophthora infestans is one of the most devastating plant pathogens worldwide. We have earlier found that the SW93-1015 potato breeding clone has an efficient resistance against P. infestans under field conditions in Sweden, which has an unusually high local diversity of the pathogen. This potato clone has characteristics that are different from classical R-gene-mediated resistance such as elevated levels of hydrogen peroxide (H2O2) under controlled conditions. Analysis of 76 F1 potato progenies from two individual crosses resulted in nearly 50% resistant clones, from both crosses. This result suggests that the SW93-1015 clone has a simplex genotype for this trait. Screening with over 50 different P. infestans effectors, containing the conserved motif RXLR (for Arg, any amino acid, Leu, Arg), revealed a specific response to Avr2, which suggests that SW93-1015 might contain a functional homolog of the R2 resistance gene. We cloned eight R2 gene homologs from SW93-1015, whereof seven have not been described before and one gene encoded a protein identical to Rpi-ABPT. Expression of this gene in potato cultivar Désirée provided R2-specific resistance, whereas other homologues did not. Using RNAseq analyses we designed a new DNA marker for the R2 resistance in SW93-1015. In summary, we have demonstrated the use of effector screening in practical breeding material and revealed the key resistance mechanism for SW93-1015.
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Affiliation(s)
- Marit Lenman
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
| | - Ashfaq Ali
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Per Mühlenbock
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Ulrika Carlson-Nilsson
- Department of Plant Breeding, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Erland Liljeroth
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
| | - Nicolas Champouret
- Wageningen UR Plant Breeding, Wageningen University and Research Centre, Wageningen, The Netherlands
| | | | - Erik Andreasson
- Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden
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