Taxonomic information	Current valid scientific name: Coniella castaneicola Synonyms: Anthasthoopa simba, Asteromella castaneicola, Coniella simba, Dothidella castaneicola, Embolidium eucalypti, Gloeosporium castaneicola, Phyllosticta castanicola, Pilidiella castaneicola (according to Index Fungorum) Name used in the EU legislation: – Order: Diaportales Family: Schizoparmaceae Common name: white rot, Coniella leaf blight Name used in the Dossier: Coniella castaneicola
Group	Fungi
EPPO code	–
Regulated status	Coniella castaneicola is neither regulated in the EU, nor listed by EPPO. Coniella castaneicola is quarantine pathogen for New Zealand (MAF Biosecurity New Zealand, 2009), Western Australia (Australian Department of Agriculture, 2014) and Korea (Korea Government, 2013).
Pest status in the UK	Coniella castaneicola is present in the UK, where it is found in the London area (Elmbridge, Wandsworth) and in south England (New Forest) (NBN Atlas, online; Dossier Section 5.0). The pathogen was recorded from England in 1991 (South Hampshire), 1997 (Surrey), 2001 (Surrey) and from Scotland in 2006 (Dawyck Botanic Garden) (NBN atlas, online). In 2015 it was found on cupules of Castanea sativa from Studland, Dorset, England (Dorset nature, online).
Pest status in the EU	Coniella castaneicola is present in the EU in Germany (Kehr and Wulf, 1993) and Latvia, where it was found on few strawberry plantations in Kurzeme, in 2007 and 2008 (Laugale et al., 2009).
Host status on Acer	The only available record for Acer sp. being a host of Coniella castaneicola is from Canada (Farr and Rossman, online, citing Nag Raj, 1993).
PRA information	Available Pest Risk Assessment: – Import health standard commodity sub‐class: fresh fruit/vegetables mango, Mangifera indica from Australia (MAF Biosecurity New Zealand, 2009); – Draft report for the non‐regulated analysis of existing policy for table grapes from Japan (Australian Department of Agriculture, 2014).
Other relevant information for the assessment
Biology	Coniella castaneicola is an ascomycete fungus causing rot of fruits and leaf spots on a number of hosts throughout the world, frequently found on living, decaying and dead leaves (Farr and Rossman, online). It is present in Africa (South Africa, Nigeria) (Van Niekerk et al., 2004; Australian department of Agriculture, 2014); Asia (China, Korea, India, Indonesia, Pakistan, Japan, Taiwan) (Farr and Rossman, online; Australian department of Agriculture, 2014; Wang and Lin, 2004); Australia (Australian department of Agriculture, 2014); North America and Caribbean (Canada, the US, Cuba) (Farr and Rossman, online); South America (Brazil) (Barreto et al., 2022).
	Coniella castaneicola is also present in Europe in Germany (Kehr and Wulf, 1993), Latvia (Laugale et al., 2009), Switzerland (Bissegger and Sieber, 1994), Russia (Melkumov, 2014) and the UK (GBIF, online; NBN Atlas, online). There is poor information on the biology and life cycle of C. castaneicola; however, its biology is considered very similar to that of Pilidiella diplodiella, so that the two species have been assessed together in Australia on grapevine (Australian Department of Agriculture, 2014). Coniella castaneicola is mostly known as a pathogen of grapevine, affecting peduncle, rachis, pedicel and berries; secondarily it is found on foliage of deciduous trees. Infections are frequently associated with hailstorms causing wounds on grapes and foliage. Heavy rain, sun scorch and wounding caused by insects can also facilitate infection to a lesser extent (Australian Department of Agriculture, 2014). The pathogen reproduces sexually and asexually, producing ascospores and conidia, respectively, both able to cause infection and dispersed by air or water. Conidia are also able to survive in the environment for long time. Infection rapidly develops at temperatures of 24–27°C, slowly at temperatures below 15°C and only slightly above 34°C. Incubation period varies from 3 to 8 days, depending on temperature, relative humidity, means of penetration and the tissue infected (Australian Department of Agriculture, 2014). Pycnidia and conidia of the pathogen overwinter on dead leaves and survive in the soil for long time (up to 15 years in case of P. diplodiella); conidia may germinate under favourable conditions and establish infection on suitable hosts. Conidia are dispersed over short distances by water splash from infected plant material as well as contaminated soil. On medium‐long distances, both ascospores and conidia may be dispersed by air currents. The movement of infected material or nursery stock and contaminated soil may also contribute to spreading of the pathogen (Australian Department of Agriculture, 2014).
Symptoms	Main type of symptoms	Typical symptom on grapevine is white rot of peduncle, rachis, pedicel and berries. The infection begins as small, pale brown, elongated depressions, which may rapidly spread in favourable conditions, causing drying and falling of berries (Australian Department of Agriculture, 2014). According to Kaneko (1981), on Castanea and Quercus species in Japan the first symptom on leaves in summer is sparse small spots pale brown, becoming greyish white in colour. The spots increase in size and form irregular‐shaped lesions causing marked leaf blight. Pycnidia are produced in the lesions on both leaf surfaces as minute black points. Usually, the disease seems not causing premature defoliation. No information about the symptoms on Acer leaves was found.
	Presence of asymptomatic plants	In Switzerland, C. castaneicola was isolated from young healthy shoots of Castanea sativa (Bissegger and Sieber, 1994).
	Confusion with other pests	On grapevine, Coniella castaneicola and Pilidiella diplodiella cause very similar symptoms, hardly distinguishable. On deciduous trees, the symptoms of C. castaneicola may possibly be confused with those of foliage diseases caused by other ascomycete fungi, also depending on the host plant. Identification of the pathogen cannot be done on a symptomatic basis and requires microscopic examination of isolates in cultures or infected plant material with fruiting structures by specialists. A good description of sexual morph of the pathogen on Castanea is provided by Jiang et al. (2021).
Host plant range	Coniella castaneicola has a variety of hosts including Acer sp., Carya sp., Castanea sativa, C. crenata, C. mollissima, C. dentata, Castanea spp., Castanopsis sempervirens, Eucalyptus grandis, Eucalyptus spp., Fragaria spp., Liquidambar styraciflua, Mangifera indica, Quercus alba, Q. rubra, Quercus sp., Rhus copallina, Rhus spp., Rosa rugosa‐prostrata, Syzygium aromaticum, Vaccinium virgatum, Vitis cordifolia and V. vinifera (Crous and Van der Linde, 1993; Farr and Rossman, online). Other host plants recognised in Europe are Aesculus hippocastanum (Melkumov, 2014) and Quercus robur (Kehr and Wulf, 1993).
Reported evidence of impact	Coniella castaneicola and Pilidiella diplodiella are mostly known as causing damage to grapevine berries, leading to crop losses and reduced marketability. In regions where hailstorms are frequent, white rot caused by C. castaneicola and P. diplodiella can lead to crop losses of 20–80% (Australian Department of Agriculture, 2014). Coniella castaneicola is also known to cause leaf and fruit diseases of strawberry in the US but no information on the economic significance was found (Australian Department of Agriculture, 2014). In Latvia the pathogen has only a little economic significance in strawberry plantations (Laugale et al., 2009). Coniella castaneicola is commonly found on leaves of Eucalyptus species, in plantations and nurseries in South Africa, Brazil and Australia, but is considered of minor importance as a pathogen causing leaf spot (Van Niekerk et al., 2004; Australian Department of Agriculture, 2014). In September 2020, C. castaneicola was observed on blueberries (Vaccinium virgatum) in Nanchang, China. The pathogen caused damage to the leaves (blight, curling, falling off), dieback and even shoot blight. Subsequently the pathogen lowered yield potential (floral buds' development was affected when the leaves fell off) (Lai et al., 2022).
Evidence that the commodity is a pathway	Although C. castaneicola has never been intercepted on plants for planting, the pathogen can move both via infected leaves on plants and contaminated soil in potted plants, therefore Acer plants for planting may be a pathway.
Surveillance information	Coniella castaneicola is not under official control in the UK (Dossier Section 5.0).