Spatial distribution of the different strains of the distinct coconut lethal yellowing-type phytoplasma species associated with the syndrome in Tanzania

Mpunami Anatolia, Pilet Fabian, Fabre Sandrine, Kullaya Alois, Dickinson Mathhew, Dollet Michel. 2021. Spatial distribution of the different strains of the distinct coconut lethal yellowing-type phytoplasma species associated with the syndrome in Tanzania. Tropical Plant Pathology, 12 p.

Journal article ; Article de recherche ; Article de revue à facteur d'impact Revue en libre accès total
Version Online first - Anglais
Use under authorization by the author or CIRAD.
Mpunami et al 2021. different strains of phytoplasma species LYTS Tanzania 10.1007_s40858-020-00407-z-1.pdf

Télécharger (1MB) | Preview

Abstract : Phytoplasmas are associated with the lethal disease of coconut palms in Tanzania (LDT). It is a destructive lethal yellowing-type syndrome (LYTS) exhibiting differences in losses between the southern districts and the northern districts. To explain these differences, the existence of variable pathogenic strains of the LDT phytoplasma was investigated using ribosomal RNA gene PCR primers. A total of 84 samples were collected from 67 palms in 14 coastal districts of Tanzania, including the low, moderate, and high incidence areas. Of these, 38 samples were studied in detail. Detected phytoplasma rDNA was characterized by either sequencing of the PCR products and/or restriction fragment length polymorphism (RFLP). Sequence analysis of the P1/P7-primed PCR products revealed several positions of variability, making it possible to distinguish two main geographical clusters. The northern cluster included samples from Tanga region only and is associated with low/moderate disease incidence. A second larger cluster included samples from the rest of the coastline between Bagamoyo and Mtwara. Five genotypes could be identified based on mutations/deletions in the P1/P7 PCR product, two within the northern cluster, and three within the southern cluster. The geographical distribution of the two clusters and the genotypes could be related to the history of coconut introductions in Tanzania. The sequences obtained also confirm that the phytoplasmas associated with LDT are significantly different from all of the other phytoplasmas associated with coconut lethal yellowing-type syndromes worldwide, and it is proposed that these phytoplasmas should be classified into their own 16Sr group.

Mots-clés Agrovoc : Phytoplasme, Maladie des plantes, Distribution spatiale, Maladie bactérienne, Cocos nucifera, Génotype, Séquence d'ADN

Mots-clés géographiques Agrovoc : République-Unie de Tanzanie

Mots-clés complémentaires : Candidatus phytoplasma, Jaunissement mortel

Mots-clés libres : Candidatus phytoplasma cocostanzaniae, East African tall coconut populations, Lethal yellowing-type syndromes, Phylogenetic tree, RFLP, RRNA gene

Classification Agris : H20 - Plant diseases
F30 - Plant genetics and breeding

Champ stratégique Cirad : CTS 4 (2019-) - Santé des plantes, des animaux et des écosystèmes

Agence(s) de financement européenne(s) : European Commission

Auteurs et affiliations

  • Mpunami Anatolia, Mikocheni Agricultural Research Institute (TZA)
  • Pilet Fabian, CIRAD-BIOS-UMR PVBMT (REU) ORCID: 0000-0003-0079-216X
  • Fabre Sandrine, CIRAD-BIOS-UMR BGPI (FRA)
  • Kullaya Alois, Mikocheni Agricultural Research Institute (TZA)
  • Dickinson Mathhew, University of Nottingham (GBR)
  • Dollet Michel, EMBRAPA (BRA) - auteur correspondant

Source : Cirad-Agritrop (

View Item (staff only) View Item (staff only)

[ Page générée et mise en cache le 2021-04-08 ]