Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks
Armillaria root rot (ARR), caused by Armillaria species and Desarmillaria tabescens, is a severe disease that affects stone fruit trees in the United States. One strategy to mitigate the impact of this disease is to develop ARR-resistant rootstocks. However, current techniques to screen Prunus speci...
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| Format: | Article |
| Language: | English |
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American Society for Horticultural Science (ASHS)
2023-09-01
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| Series: | HortScience |
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| Online Access: | https://journals.ashs.org/hortsci/view/journals/hortsci/58/10/article-p1163.xml |
| _version_ | 1797656982659792896 |
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| author | Pratima Devkota Amy Iezzoni Ksenija Gasic Gregory Reighard Raymond Hammerschmidt |
| author_facet | Pratima Devkota Amy Iezzoni Ksenija Gasic Gregory Reighard Raymond Hammerschmidt |
| author_sort | Pratima Devkota |
| collection | DOAJ |
| description | Armillaria root rot (ARR), caused by Armillaria species and Desarmillaria tabescens, is a severe disease that affects stone fruit trees in the United States. One strategy to mitigate the impact of this disease is to develop ARR-resistant rootstocks. However, current techniques to screen Prunus species for resistance to ARR are time-consuming, labor-intensive, and may not fully replicate field conditions. To address these limitations, we developed a new rapid in vitro screening assay, which uses roots of 2-year-old Prunus rootstock genotypes. We screened 12 Prunus genotypes against Armillaria mellea, Armillaria solidipes, and Desarmillaria tabescens in vitro. Freshly excavated root segments were placed next to or on top of fungal cultures. After 21 days, the circumferential percentage and horizontal length of the fungal colonization and the ability of the fungus to enter through root periderm were evaluated. The root tissue surrounding the infection was also evaluated to assess any response reactions against the ARR pathogens. Our results showed that inoculated root tissues displayed signs of fungal infection, and infection and host responses varied among the Prunus genotypes. Host responses similar to those observed in the field, such as compartmentalization of infected tissue with barrier zones, necrophylactic periderm formation, and callus formation on root surfaces, were observed and were more evident in less susceptible genotypes. In conclusion, our newly developed assay, which uses freshly excavated roots from 2-year-old rootstocks, can rapidly screen Prunus genotypes for resistance to ARR. |
| first_indexed | 2024-03-11T17:37:51Z |
| format | Article |
| id | doaj.art-6f36587ad78e45e6b9d4ecf30d59af9a |
| institution | Directory Open Access Journal |
| issn | 2327-9834 |
| language | English |
| last_indexed | 2024-03-11T17:37:51Z |
| publishDate | 2023-09-01 |
| publisher | American Society for Horticultural Science (ASHS) |
| record_format | Article |
| series | HortScience |
| spelling | doaj.art-6f36587ad78e45e6b9d4ecf30d59af9a2023-10-18T17:14:47ZengAmerican Society for Horticultural Science (ASHS)HortScience2327-98342023-09-015810https://doi.org/10.21273/HORTSCI17196-23Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young RootstocksPratima Devkota 0Amy Iezzoni1Ksenija Gasic 2Gregory Reighard 3Raymond Hammerschmidt 4Department of Plant, Soil and Microbial Sciences, Michigan State University Department of Horticulture, Michigan State UniversityDepartment of Plant and Environmental Sciences, Clemson UniversityDepartment of Plant and Environmental Sciences, Clemson UniversityDepartment of Plant, Soil and Microbial Sciences, Michigan State UniversityArmillaria root rot (ARR), caused by Armillaria species and Desarmillaria tabescens, is a severe disease that affects stone fruit trees in the United States. One strategy to mitigate the impact of this disease is to develop ARR-resistant rootstocks. However, current techniques to screen Prunus species for resistance to ARR are time-consuming, labor-intensive, and may not fully replicate field conditions. To address these limitations, we developed a new rapid in vitro screening assay, which uses roots of 2-year-old Prunus rootstock genotypes. We screened 12 Prunus genotypes against Armillaria mellea, Armillaria solidipes, and Desarmillaria tabescens in vitro. Freshly excavated root segments were placed next to or on top of fungal cultures. After 21 days, the circumferential percentage and horizontal length of the fungal colonization and the ability of the fungus to enter through root periderm were evaluated. The root tissue surrounding the infection was also evaluated to assess any response reactions against the ARR pathogens. Our results showed that inoculated root tissues displayed signs of fungal infection, and infection and host responses varied among the Prunus genotypes. Host responses similar to those observed in the field, such as compartmentalization of infected tissue with barrier zones, necrophylactic periderm formation, and callus formation on root surfaces, were observed and were more evident in less susceptible genotypes. In conclusion, our newly developed assay, which uses freshly excavated roots from 2-year-old rootstocks, can rapidly screen Prunus genotypes for resistance to ARR.https://journals.ashs.org/hortsci/view/journals/hortsci/58/10/article-p1163.xmlbarrier zonecompartmentalizationperidermroot defense |
| spellingShingle | Pratima Devkota Amy Iezzoni Ksenija Gasic Gregory Reighard Raymond Hammerschmidt Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks HortScience barrier zone compartmentalization periderm root defense |
| title | Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks |
| title_full | Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks |
| title_fullStr | Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks |
| title_full_unstemmed | Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks |
| title_short | Rapid In Vitro Screening of Prunus Genotypes for Resistance to Armillaria Root Rot Using Roots of Young Rootstocks |
| title_sort | rapid in vitro screening of prunus genotypes for resistance to armillaria root rot using roots of young rootstocks |
| topic | barrier zone compartmentalization periderm root defense |
| url | https://journals.ashs.org/hortsci/view/journals/hortsci/58/10/article-p1163.xml |
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