Detection and Molecular Characterization of Phytoplasmas Associated With Diseases in Squash and Cucumber in Türkiye
JOURNAL OF PHYTOPATHOLOGY, cilt.174, sa.5, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 174 Sayı: 5
- Basım Tarihi: 2026
- Doi Numarası: 10.1111/jph.70386
- Dergi Adı: JOURNAL OF PHYTOPATHOLOGY
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CAB Abstracts, Environment Index, Geobase, Academic Search Ultimate (EBSCO), Natural Science Collection (ProQuest), Biological Science Database (ProQuest), Biomedical Reference Collection: Corporate Edition (EBSCO)
- Hatay Mustafa Kemal Üniversitesi Adresli: Evet
Özet
Phytoplasma-associated diseases pose a serious threat to cucurbit production worldwide. In October 2024, severe phyllody and virescence symptoms were observed in cucumber (Cucumis sativus L.) and summer squash (Cucurbita pepo L.) grown in K & imath;r & imath;khan district, Hatay Province, T & uuml;rkiye. Considering that all flowers on infected plants exhibited phyllody, yield losses in affected plants were estimated to reach up to 100%. A total of 27 symptomatic plant samples, including 19 squash and 8 cucumber plants, were collected and subjected to molecular analyses. Universal primer pairs F1/R0 and R16F2n/R2 were used to amplify the 16S rRNA gene (direct and nested PCR, respectively), and all symptomatic samples tested positive for phytoplasma presence, whereas no amplification was detected in asymptomatic control plants. BLASTn analysis of the 16S rRNA gene indicated that the detected phytoplasma belongs to 'Candidatus Phytoplasma australasiaticum'. To further characterize the detected phytoplasma, multilocus analyses targeting the secA, tuf, imp and SAP11 genes were performed. BLASTn analyses of the representative 16S rRNA, secA, tuf and imp gene sequences revealed 99.93%-100% nucleotide sequence identity with reference strains of 'Ca. P. australasiaticum', cucumber phyllody phytoplasma, and tomato big bud phytoplasma. Phylogenetic trees based on the 16S rRNA, secA, tuf and imp genes showed that the Hatay isolates clustered within the peanut witches' broom subgroup (16SrII-D). To the best of our knowledge, this study represents the first molecular evidence of cucumber and summer squash phyllody associated with 'Ca. P. australasiaticum' (16SrII-D) in T & uuml;rkiye. These findings expand current knowledge of phytoplasma diversity in cucurbit crops and demonstrate the value of multilocus sequence analyses for molecular characterization and phylogenetic inference. Further studies on disease epidemiology, insect vectors and management strategies are needed to better understand and mitigate the spread of this phytoplasma in T & uuml;rkiye.