Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya

Ralstonia solanacearum is a pathogen causing bacterial wilt disease of potato, resulting in 70% potato production losses in Kenya. A study was conducted to determine the diversity of R. solanacearum species complex strains within the main potato-growing regions of Kenya. Potato tubers were collected...

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Autores principales: Okiro, L.A., Mulwa, R.M., Oyoo, M.E., Machuka, Eunice M., Parker, M.
Formato: Journal Article
Lenguaje:Inglés
Publicado: Scientific Societies 2022
Materias:
Acceso en línea:https://hdl.handle.net/10568/119612
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author Okiro, L.A.
Mulwa, R.M.
Oyoo, M.E.
Machuka, Eunice M.
Parker, M.
author_browse Machuka, Eunice M.
Mulwa, R.M.
Okiro, L.A.
Oyoo, M.E.
Parker, M.
author_facet Okiro, L.A.
Mulwa, R.M.
Oyoo, M.E.
Machuka, Eunice M.
Parker, M.
author_sort Okiro, L.A.
collection Repository of Agricultural Research Outputs (CGSpace)
description Ralstonia solanacearum is a pathogen causing bacterial wilt disease of potato, resulting in 70% potato production losses in Kenya. A study was conducted to determine the diversity of R. solanacearum species complex strains within the main potato-growing regions of Kenya. Potato tubers were collected in different potato-growing regions of Kenya from visibly wilted potato plants as well as samples of tomato, irrigation water, and cultures for pathogen isolation. Genomic DNA was isolated from 135 purified cultures of RSSC isolates and PCR-amplified using multiplex and sequevar primers targeting the endoglucanase (egl) partial gene sequences. Pathogenicity tests using R. solanacearum strain (phylotype II sequevar I) were done on the cultivars Kenya Karibu, Shangi, Chulu, Wanjiku, and MoneyMaker. Phylogenetic analysis of the partial egl gene identified two genospecies, R. pseudosolanacearum sp. nov. (1.5%) and R. solanacearum (98.5%). All R. solanacearum strains clustered in sequevar I and were distributed in all the potato-growing regions surveyed. The cultivars were grown in a greenhouse for two cycles in a randomized complete block design and inoculated with R. solanacearum strain. The severity scores were assessed and the area under the disease progress curve (AUDPC) was determined. All the cultivars tested for pathogenicity exhibited wilting symptoms at varying intervals after infection, with none showing complete resistance to R. solanacearum. Cultivar Shangi exhibited minimum disease severity and progression of 41.14% and AUDPC of 1041.7, respectively, while 'Kenya Karibu' was the most susceptible with a high progression rate of 68.24% and AUDPC of 1897.5, respectively. 'MoneyMaker', 'Chulu', and 'Wanjiku' showed no significant difference in disease severity, depicting a simultaneous rate of infection among them. These findings provide valuable information to better understand the pathogen genetic diversity in Kenya and how it spreads.
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spelling CGSpace1196122025-12-02T10:59:51Z Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya Okiro, L.A. Mulwa, R.M. Oyoo, M.E. Machuka, Eunice M. Parker, M. pathogenicity potatoes ralstonia solanacearum phylogenetics Ralstonia solanacearum is a pathogen causing bacterial wilt disease of potato, resulting in 70% potato production losses in Kenya. A study was conducted to determine the diversity of R. solanacearum species complex strains within the main potato-growing regions of Kenya. Potato tubers were collected in different potato-growing regions of Kenya from visibly wilted potato plants as well as samples of tomato, irrigation water, and cultures for pathogen isolation. Genomic DNA was isolated from 135 purified cultures of RSSC isolates and PCR-amplified using multiplex and sequevar primers targeting the endoglucanase (egl) partial gene sequences. Pathogenicity tests using R. solanacearum strain (phylotype II sequevar I) were done on the cultivars Kenya Karibu, Shangi, Chulu, Wanjiku, and MoneyMaker. Phylogenetic analysis of the partial egl gene identified two genospecies, R. pseudosolanacearum sp. nov. (1.5%) and R. solanacearum (98.5%). All R. solanacearum strains clustered in sequevar I and were distributed in all the potato-growing regions surveyed. The cultivars were grown in a greenhouse for two cycles in a randomized complete block design and inoculated with R. solanacearum strain. The severity scores were assessed and the area under the disease progress curve (AUDPC) was determined. All the cultivars tested for pathogenicity exhibited wilting symptoms at varying intervals after infection, with none showing complete resistance to R. solanacearum. Cultivar Shangi exhibited minimum disease severity and progression of 41.14% and AUDPC of 1041.7, respectively, while 'Kenya Karibu' was the most susceptible with a high progression rate of 68.24% and AUDPC of 1897.5, respectively. 'MoneyMaker', 'Chulu', and 'Wanjiku' showed no significant difference in disease severity, depicting a simultaneous rate of infection among them. These findings provide valuable information to better understand the pathogen genetic diversity in Kenya and how it spreads. 2022-06-01 2022-05-21T01:16:51Z 2022-05-21T01:16:51Z Journal Article https://hdl.handle.net/10568/119612 en Open Access Scientific Societies Okiro, L. A.; Mulwa, R. M.; Oyoo, M. E.; Machuka, E. M.; Parker, M. L.; Pelle, R. 2022. Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya. Plant Disease. ISSN 1943-7692.
spellingShingle pathogenicity
potatoes
ralstonia solanacearum
phylogenetics
Okiro, L.A.
Mulwa, R.M.
Oyoo, M.E.
Machuka, Eunice M.
Parker, M.
Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya
title Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya
title_full Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya
title_fullStr Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya
title_full_unstemmed Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya
title_short Phylogenetic Distribution of Ralstonia solanacearum Species Complex Populations in Potato in Kenya
title_sort phylogenetic distribution of ralstonia solanacearum species complex populations in potato in kenya
topic pathogenicity
potatoes
ralstonia solanacearum
phylogenetics
url https://hdl.handle.net/10568/119612
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