This is the first report of chrysanthemum virus B (CVB) and chrysanthemum chlorotic mottle viroid (CChMVd) on Chrysanthemum × morifolium cultivars, in South Africa. Samples were collected from plants showing vein clearing, mosaic and chlorosis, in the Western Cape province. RNAtag-seq was applied and indicated the presence of CVB in all four samples and the co-infection with CChMVd in one sample. The presence of CVB and CChMVd were confirmed using RT-PCR and Sanger sequencing.
During 2021 surveys, greengage witches’-broom (GWB) and decline (GD) diseases were respectively observed in Fars and Yazd provinces of Iran. Presence of phytoplasma in the symptomatic plants was confirmed by PCR amplifications of 16S rRNA gene. Sequence analyses showed affiliation of the GWB and GD phytoplasmas to‘Candidatus Phytoplasma phoenicium’ (16SrIX-B) and‘Ca. P. aurantifolia’ (16SrII-C) related strains, respectively. This is the first report of phytoplasma diseases of greengage in Iran and probably in the world.
This paper reports the first occurrence of Lasiodiplodia theobromae in Brazil nut (Bertholletia excelsa). Cankers were found on branches of 3-year-old Brazil nut plants in Belém, Pará, Brazil. The symptomatic plants displayed reddish vascular lesions. The pathogen was identified using morphological and phylogenetic analyses. Koch’s postulates were fulfilled, confirming the first occurrence of L. theobromae in Brazil nut.
In August 2021, jimson weed (Datura stramonium) plants growing as weeds in potato fields in Bolu province, Turkey, exhibited leaf spots with dark concentric rings. Sunken and lens-shaped lesions with a light center were also frequently observed on petioles, branches, and stems. Based on morphological characteristics and phylogenetic analysis of the transcription elongation factor 1-α, RNA polymerase second largest subunit, and glyceraldehyde-3- phosphate dehydrogenase loci, the causal agent was identified as Alternaria crassa. The pathogen was successfully re-isolated from inoculated jimson weed plants in the pathogenicity assay, proving Koch’s postulates. Alternaria crassa caused necrotic lesions on potato plants, similar to those of early blight, confirming them as an alternative host of the pathogen. This is apparently the first report of leaf spot caused by A. crassa on jimson weed in Turkey.
Fig (Ficus carica) trees exhibited symptoms of little leaf, mottling and deformation in Sanliurfa province, Turkey. Poylmerase chain reaction (PCR) through direct and nested-PCR, phylogeny based on the sequence analysis revealed that the infecting agent was closely related to ‘Candidatus Phytoplasma aurantifolia’ (16SrII-B subgroup). This is the first report of Ca. P. aurantifolia in fig trees in Turkey.
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