Phytophthora pseudocitrophthora, A New Pathogen of Carnations Causing Root Rot and Basal Stem Necroses in Türkiye

İ. Kurbetli G. Sülü S. Woodward M. Aydoğdu T. I. Burgess

Jul 2026 · Plant Pathology · Vol 75 · 0 citations · 25 references

TL;DR

Pathogenicity trials using soil with inoculated wheat grains showed that isolates induced main root rot and basal stem necroses consistent with field symptoms and significantly reducing root biomass in carnation seedlings within 3 months.

Abstract

A previously unreported root rot and basal stem necrosis disease was observed in carnation (Dianthus caryophyllus) plants grown in greenhouses in Yalova Province, Türkiye, in 2018. A Phytophthora species was consistently isolated from symptomatic root and vascular tissues. Morphological examination revealed a heterothallic species with papillate, usually non‐caducous sporangia (sometimes with double papillae) having ovoid, obpyriform, ellipsoid or nearly spherical shapes, lateral attachment of sporangiophores and spherical chlamydospores in cultures. Mycelial growth on carrot agar occurred between 9.5°C and 31.5°C, with optimum growth at 25°C. Phylogenetic analyses performed using data from three nuclear (ITS, β‐tubulin and heat shock protein 90) and four mitochondrial regions (cytochrome c oxidase subunit 1, cytochrome c oxidase subunit 2, NADH dehydrogenase subunit 1 and ribosomal protein L10) placed isolates in a monophyletic subclade of Phytophthora Clade 2a, matching the recently described species Phytophthora pseudocitrophthora. Pathogenicity trials using soil with inoculated wheat grains showed that isolates induced main root rot and basal stem necroses consistent with field symptoms and significantly reducing root biomass in carnation seedlings within 3 months. All inoculated isolates were reisolated, fulfilling Koch's postulates. This study presents the first report of P. pseudocitrophthora causing disease in carnations and highlights its potential significance in ornamental plant pathology.

DOI Semantic Scholar

View source

Similar papers

Review Open access Aug 2026

First Report of Phytopythium vexans Causing Stem and Leaf Necrosis on Rubber Tree (Hevea brasiliensis): Biological Characteristics and Fungicide Sensitivity

The findings provide a theoretical foundation for accurate disease diagnosis, epidemiological surveillance, and the development of effective chemical control strategies for rubber plantations.

Zhi-Ying Cai, Li-Li He, Li-Ming Dai et al. · Plants · 0 citations

Jul 2026

First report of Globisporangium irregulare causing wilt and root rot on greenhouse-grown common sage in the United States

This is the first report of G. irregulare infecting common sage, and recognizing G. irregulare as a pathogen of common sage is important for effective disease management and reducing losses in the greenhouse.

Cora M. Kenderdine · Plant Disease · 0 citations

Review Jul 2026

First report of Phytophthora ramorum causing leaf blight on Ceratonia siliqua in the United States

To the authors' knowledge, this is the first report of P. ramorum occurring on C. siliqua globally and the first confirmation of Koch’s postulates for this host-pathogen combination.

Dinh-Hieu Pham, T. Pastalka, Huiying Liu et al. · Plant Disease · 0 citations

Jul 2026

Multilocus evidence of Phytophthora palmivora and P. tropicalis as causal agents of cacao black pod disease in southern Mexico

This study provides the first multilocus evidence of the coexistence of P. palmivora and P. tropicalis in cacao plantations in southern Mexico and redefine the known species composition of the cacao black pod disease complex in Mexico.

Marilyn Estefania Yzquierdo-Alvarez, C. Ortíz-García, J. Rincón-Ramírez et al. · Tropical Plant Pathology · 0 citations

Aug 2026

Taxonomy, Biological Characterization, and Fungicide Sensitivity of a New Species, Cladobotryum hypsigum, Causing Cobweb Disease in Gold Mushroom (Pholiota conissans) in China.

In vitro fungicide sensitivity assays, performed using the hyphal growth inhibition method against six common fungicides, demonstrated that Carbendazim was the most effective agent, indicating significant selectivity.

Fang Wu, Jing Tu, Zhu-Xiang Liu et al. · Plant Disease · 0 citations

Open access Jul 2026

First report of Cladosporium uredinicola causing leaf spot on eggplant (Solanum melongena L.) in Iraq

Leaf spot diseases represent a major constraint to eggplant production under favourable environmental conditions. Therefore, potential pathogenicity of the fungus Cladosporium uredinicola on the leaves of eggplant (Solanum melongena L.), cultivar 'Barcelona F1', was confirmed in this study. Symptomatic leaf tissues were obtained from several greenhouse locations in Basrah governorate, southern Iraq. The first isolation of the fungus was done on potato dextrose agar (PDA) plates, followed by the investigation of morphological and microscopic features. Cladosporium uredinicola fungal growth on the PDA medium was olive-green to dark olivaceous-brown pigmentation and irregular margins, while the microscope conidiophores were light to medium olive colorin colour, smooth to finely roughened, bearing short terminal chains of 2–5 conidia. Pale olivaceous-brown, ellipsoid to oblong in shape, smooth-walled conidia were observed with 0–3 transverse septa. The internal transcribed spacer (ITS) region was targeted for confirming the identification; the ITS sequence was deposited in the National Center for Biotechnology Information (NCBI) GenBank database under accession number PV961371.1. Pathogenicity trials were followed under greenhouse conditions, revealing the pathogenic effect of C. uredinicola on eggplant leaves, showing necrotic lesion symptoms, which initially appeared after five days post-inoculation as small brown, circular to irregular margins, subsequently extended and coalesced into large spots and patches with chlorosis symptoms and ended with leaf abscission. The fungal pathogen was re-isolated from diseased leaves to confirm Koch's postulates. The current study represents the first report of C. uredinicola as a potential pathogen on eggplant leaves in Iraq.

A. M. Angham, H. A. Mohammed · Plant Science Today · 0 citations