Calonectria queenslandica : Causal Agent of Eucalyptus Leaf Blight in Southern China
Calonectria leaf blight caused by Calonectria spp. is among the most serious diseases affecting the health and sustainability of Eucalyptus plantations in southern China. Recent outbreaks of this disease in GuangDong Province prompted a need to identify the species involved. Typical symptoms of Calo...
| Publié dans: | Plant disease. - 1997. - 107(2023), 3 vom: 30. März, Seite 730-742 |
|---|---|
| Auteur principal: | |
| Autres auteurs: | , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2023
|
| Accès à la collection: | Plant disease |
| Sujets: | Journal Article C. pseudoreteaudii C. reteaudii Calonectria aconidialis mating type pathogenicity |
| Résumé: | Calonectria leaf blight caused by Calonectria spp. is among the most serious diseases affecting the health and sustainability of Eucalyptus plantations in southern China. Recent outbreaks of this disease in GuangDong Province prompted a need to identify the species involved. Typical symptoms of Calonectria leaf blight were observed on 2-year-old Eucalyptus urophylla × E. grandis trees in a plantation in the ZhaoQing region. In total, 38 Calonectria isolates were collected from 32 diseased trees. All isolates were identified using DNA sequence analyses of the translation elongation factor 1-α (tef1), β-tubulin (tub2), calmodulin (cmdA), and histone H3 (his3) gene regions. Phylogenetic analyses revealed that Calonectria queenslandica was the dominant species, accounting for 81.6% of the isolates collected. Other species isolated included C. pseudoreteaudii (10.5%), C. reteaudii (5.3%), and C. aconidialis (2.6%). This is the first report of C. queenslandica in China and all isolates had identical sequences in all four gene regions. PCR amplification using primers targeting the MAT1-1-1 and MAT1-2-1 genes in all C. queenslandica isolates revealed that only the MAT1-2 idiomorph was present. The results suggest that C. queenslandica was introduced into the sampled area with very limited genetic diversity. Pathogenicity tests were conducted on two Eucalyptus genotypes widely planted in the GuangDong Province using isolates representing all species collected. The results showed that these species could all cause disease but the predominance of C. queenslandica on infected trees suggests that it is the major driver of the disease problem studied. Different Eucalyptus genotypes used in the pathogenicity tests differed in susceptibility to infection by the Calonectria spp. tested, providing opportunities to avoid leaf blight by deploying disease-tolerant planting stock |
|---|---|
| Description: | Date Completed 05.04.2023 Date Revised 05.04.2023 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 0191-2917 |
| DOI: | 10.1094/PDIS-01-22-0196-RE |