Phytophthora pseudocryptogea is increasingly recognized as a significant threat to Cycas revoluta cultivation in Mediterranean nursery systems. This study assessed the pathogenicity and relative aggressiveness of P. pseudocryptogea, P. nicotianae, and P. multivora through controlled stem-wounding and soil-infestation assays supported by longitudinal ANOVA models and post hoc comparisons. The results show that P. pseudocryptogea is the only species capable of infecting and colonizing C. revoluta, showing rapid symptom onset, high disease severity, and consistent re-isolation from symptomatic tissues. Conversely, P. multivora and P. nicotianae failed to induce significant symptoms and were statistically indistinguishable from the control across all inoculation methods. Time-series analyses revealed clear species-specific virulence trajectories, highlighting differences in pathogenic behavior among taxa. The findings support P. pseudocryptogea as an emerging pathogen in Mediterranean nursery environments and emphasize the importance of integrating longitudinal analytical frameworks to improve the resolution of pathogenicity assessments.

The spread of mistletoe, which mainly affects Scots pine in Europe’s managed forests, has become a serious ecological and economic problem, exacerbated by climate change and drought stress. Research into mistletoe-associated mycobiota provides crucial insights into the biology, ecology and distribution of these fungi and forms the basis for sustainable plant protection and effective management strategies. The aim of this study was to identify the fungal species associated with mistletoe (Viscum album L.) at 75 sites across Poland, with a focus on the northeastern regions of the country. The field work included a systematic and targeted search using the transect method, followed by laboratory analysis, during which fungal samples were prepared and examined under both light and scanning electron microscopes. The genetic analysis was carried out using ITS sequencing to confirm the presence of pathogen-specific fungi in the majority of V. album samples examined. The results showed four fungal species associated with the mycobiota of mistletoe: Sphaeropsis visci, Plenodomus visci, Cylindrodendrum hubeiense and Septoria krystynae. It is noteworthy that two of these species (P. visci and C. hubeiense) have not yet been detected in Poland. Based on these findings, the distribution areas of the identified fungal species were mapped accordingly.

Quambalaria eucalypti is a fungal pathogen that causes leaf spot, shoot blight, and stem canker on Eucalyptus spp. Early diagnosis of the disease is difficult, although the symptoms are clear in its advanced phase. To enable a rapid and sensitive screening of asymptomatic or latently infected plant material for Q. eucalypti, a SYBR green-based real-time PCR assay targeting the partial histone-H3 region was developed. The assay demonstrated specificity for Q. eucalypti, not showing cross-reactivity with other Quambalaria species or the other eucalyptus fungal pathogens tested. The primers developed in this study ensured high analytical sensitivity, allowing the detection of Q. eucalypti DNA concentrations as low as 10 fg DNA from asymptomatic plants. The robustness and efficacy of the assay was demonstrated by interlaboratory comparisons with similar results. This newly developed quantitative PCR assay can be used for more comprehensive epidemiological investigations, testing the plant material in known Q. eucalypti distribution areas for early management strategies, or collecting data for resistance breeding programs.

Ash trees are an important component of both forests and the countryside. Emerging new diseases like ash dieback poses new challenges to Fraxinus spp., which not only have to adapt to global warming but also defend themselves against new threats from pathogenic fungi and insect pests. A new species of fungus, Hymenoscyphus fraxineus, has arrived in Europe from Asia and has severely damaged shoots which alters the structure of ash tree crowns. While some older trees have survived, younger trees are dying en masse, so the only hope is that the surviving trees will produce a younger generation that may be more resistant to the new diseases. The fine roots of ash trees are also attacked by pathogenic oomycetes, and others by Armillaria spp. The current stressed condition of ash trees in Europe is exacerbated by a new threat from insects. Agrillus planipennis, emerald ash borer, migrating from the east (from near Moscow airport) towards the borders of the European Union, killing thousands of ash trees on its way. This raises the question of future prospects for ash cultivation in Europe. This article takes a closer look at the information described in the literature.

A dieback was observed on three-year-old pot-grown plants of Cycas revoluta in Sicily (Italy). Symptoms, including stunting, yellowing and blight of the leaf crown, root rot and internal browning and decay of the basal stem, closely resembled the Phytophthora root and crown rot syndrome, common in other ornamentals. Isolations from rotten stem and roots, using a selective medium, and from rhizosphere soil of symptomatic plants, using leaf baiting, yielded three Phytophthora species, P. multivora, P. nicotianae and P. pseudocryptogea, were obtained. Isolates were identified by both morphological characters and DNA barcoding analysis, using three gene regions: ITS, β-tub and COI. Phytophthora pseudocryptogea was the sole species isolated directly from the stem and roots. The pathogenicity of the isolates of the three Phytophthora species was tested on one-year-old potted plants of C. revoluta, using both stem inoculation by wounding, and root inoculation through infested soil. Phytophthora pseudocryptogea was the most virulent and, like P. nicotianae, reproduced all the symptoms of natural infections, while P. multivora was the least virulent and induced solely very mild symptoms. Phytophthora pseudocryptogea was identified as the causal agent of the decline of C. revoluta, as it was re-isolated from both the roots and stems of artificially infected symptomatic plants, thus fulfilling Koch's postulates.

Paulownia species are fast growing trees native to China, which are being grown in managed plantings in several European countries for the production of wood and biomasses. In 2018, wilting, stunting, leaf yellowing, and collapse, as a consequence of root and crown rot, were observed in around 40% of trees of a 2-year-old planting of Paulownia elongata × P. fortunei in Calabria (Southern Italy). Two species of Phytophthora were consistently recovered from roots, basal stem bark, and rhizosphere soil of symptomatic trees and were identified as Ph. nicotianae and Ph. palmivora on the basis of both morphological characteristics and phylogenetic analysis of rDNA ITS sequences. Koch’s postulates were fulfilled by reproducing the symptoms on potted paulownia saplings transplanted into infested soil or stem-inoculated by wounding. Both Phytophthora species were pathogenic and caused root rot and stem cankers. Even though P. palmivora was the only species recovered from roots of naturally infected plants, in pathogenicity tests through infested soil P. nicotianae was more virulent. This is the first report of Phytophthora root and crown rot of a Paulownia species in Europe. Strategies to prevent this emerging disease include the use of healthy nursery plants, choice of well-drained soils for new plantations, and proper irrigation management.

Late blight caused by the oomycete Phytophthora infestans is a disease of potato and tomato of worldwide relevance and is widespread throughout Europe and the Mediterranean region. While pathogen populations in northern Europe have been sampled and characterized for many years, the genetic structure of populations from southern Europe, including Italy, has been less studied. Between 2018 and 2019, we collected 91 samples of P. infestans from potato and tomato crops in Italy, Algeria, and Tunisia on FTA cards and genotyped them using 12-plex microsatellites. These samples were compared to genotypes of P. infestans previously collected within the framework of the EuroBlight network and from published sources. Four clonal lineages were identified: 13_A2 (Blue 13), 2_A1, 23_A1, and 36_A2. Two other isolates collected could not be matched to any currently known clonal lineage. The 13_A2 and 36_A2 lineages were found exclusively in southern Italy and Algeria, while 2_A1 was only found in Algeria. This is the first report of the 36_A2 lineage in Italy. Two isolates from Solanum nigrum were 13_A2, suggesting this weed host could be a reservoir of inoculum. The 23_A1 lineage was found widely on infected tomato crops in Italy and is the same as the lineage US-23 that is widespread in North America. Differences in genotypes across the country suggests that there may be different sources of introduction into Italy, possibly via infected seed tubers from other countries in Europe, tubers for consumption from North Africa, or tomatoes.

Black spot is a major foliar disease of sweet basil (Ocimum basilicum) present in a typical cultivation area of northern Italy, including the Liguria and southern Piedmont regions, where this aromatic herb is an economically important crop. In this study, 15 Colletotrichum isolates obtained from sweet basil plants with symptoms of black spot sampled in this area were characterized morphologically and by nuclear DNA analysis using internal transcribed spacers (ITS) and intervening 5.8S nrDNA as well as part of the β-tubulin gene (TUB2) regions as barcode markers. Analysis revealed all but one isolate belonged to the recently described species C. ocimi of the C. destructivum species complex. Only one isolate was identified as C. destructivum sensu stricto (s.s.). In pathogenicity tests on sweet basil, both C. ocimi and C. destructivum s.s. isolates incited typical symptoms of black spot, showing that although C. ocimi prevails in this basil production area, it is not the sole causal agent of black spot in northern Italy. While no other hosts of C. ocimi are known worldwide, the close related species C. destructivum has a broad host range, suggesting a speciation process of C. ocimi within this species complex driven by adaptation to the host.

HomePlant DiseaseVol. 104, No. 8First Report of Postharvest Fruit Rot Caused by Fusarium sacchari on Lady Finger Banana in Italy PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Postharvest Fruit Rot Caused by Fusarium sacchari on Lady Finger Banana in ItalyM. Riolo, F. Aloi, R. Faedda, S. O. Cacciola, and A. PaneM. Riolohttp://orcid.org/0000-0001-8058-5624Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, ItalyCouncil for Agricultural Research and Agricultural Economy Analysis, Research Centre for Olive, Citrus and Tree Fruit - Rende CS (CREA-OFA), 87036 Rende, ItalyDepartment of Agricultural Science, Mediterranean University of Reggio Calabria, 89122 Reggio Calabria, ItalySearch for more papers by this author, F. AloiDepartment of Agriculture, Food and Environment, University of Catania, 95123 Catania, ItalyDepartment of Agricultural, Food and Forest Sciences, University of Palermo, 90128 Palermo, ItalySearch for more papers by this author, R. FaeddaDepartment of Agriculture, Food and Environment, University of Catania, 95123 Catania, ItalySearch for more papers by this author, S. O. CacciolaDepartment of Agriculture, Food and Environment, University of Catania, 95123 Catania, ItalySearch for more papers by this author, and A. Pane†Corresponding author: A. Pane; E-mail Address: apane@unict.ithttp://orcid.org/0000-0002-8457-1788Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, ItalySearch for more papers by this author AffiliationsAuthors and Affiliations M. Riolo1 2 3 F. Aloi1 4 R. Faedda1 S. O. Cacciola1 A. Pane1 † 1Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy 2Council for Agricultural Research and Agricultural Economy Analysis, Research Centre for Olive, Citrus and Tree Fruit - Rende CS (CREA-OFA), 87036 Rende, Italy 3Department of Agricultural Science, Mediterranean University of Reggio Calabria, 89122 Reggio Calabria, Italy 4Department of Agricultural, Food and Forest Sciences, University of Palermo, 90128 Palermo, Italy Published Online:3 Jun 2020https://doi.org/10.1094/PDIS-01-20-0143-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat Thin-skinned banana ‘Lady Finger’, a diploid hybrid (AA) of Musa acuminata, is grown for its edible fruits and as an ornamental. In April 2019, in an open-air market in Catania (southern Italy), 42% of fruits in a stock of 2,000 pounds of this banana cultivar showed numerous small, dark circular spots and dark brown to black, sunken lesions, lenticular in shape, along with crown, finger-stalk, and tip-end rot. The surface of lesions was covered with salmon-pink spore masses. The stock originated from Costa Rica and was repacked in Italy using transparent plastic wrapping, each containing a hand of six fruits. A Fusarium species (71% of isolations) was recovered on potato dextrose agar (PDA) supplemented with 100 µg/ml of streptomycin and incubated at 27 ± 1°C for 5 to 7 days from 35 randomly sampled symptomatic fruits. A total of 71 isolates were obtained as pure cultures by single-spore isolations. On PDA, all isolates initially had white or light purple aerial mycelium that became violet with age and had an optimum growth of 27°C (7.6 to 12.3 mm/day). On carnation leaf agar, the cultures produced slender, slight falcate, three- to four-septate macroconidia with an acute apical cell (17.5 to 44.2 × 2.2 to 3.1 µm) and oval and slender microconidia arranged in false heads (5.1 to 14.0 × 1.7 to 3.8 μm). The conidiophores were mostly branched at one level. The β-tubulin (β-tub) and translation elongation factor 1 (tef1) genes of all isolates were amplified from gDNA using βt2α/βt2β (Glass and Donaldson 1995) and EF1/EF2 (O’Donnell et al. 1998) primers, respectively. Pairwise alignments of β-tub and tef1 sequences of all isolates showed 325/325 bp (100%) and 613/615 bp (99.67%) similarity, respectively, with those of Fusarium sacchari in GenBank (accession nos. KU603910 and GU377296, respectively). Being all the same, only the sequences of isolate CBS 145949 were deposited in GenBank (MN255816 and MN255818, respectively). Based on morphological (Leslie and Summerell 2006; Leslie et al. 2005) and molecular features, isolates were identified as F. sacchari (E.J. Butler) W. Gams. Pathogenicity of CBS 145949 was tested by inoculating 24 wounded and 24 unwounded ripe fruits of Lady Finger, surface disinfected with 70% ethanol and rinsed with sterile distilled water. Unwounded fruits were inoculated with mycelium disks (Abd Murad et al. 2017), whereas control fruits were inoculated with sterile agar disks. For wound inoculations, a 1-mm wound was made on the peel with a sterilized needle, and a drop of 5 µl of spore suspension (5 × 105 spores/ml) was placed on three distinct spots per fruit. Twelve control fruits were inoculated with sterile distilled water. Fruits were incubated in a humid chamber at 27°C. All wounded inoculated fruits showed the same rot symptoms as those observed in the market 7 days after inoculation. Control and unwounded inoculated fruits remained symptomless. F. sacchari was reisolated solely from inoculated fruits. These results indicate F. sacchari is a wound parasite on banana fruits. The high incidence of fruit rot observed in this stock was probably due to improper postharvest management and poor packaging. F. sacchari has been reported as pathogen of banana in several producing countries (Abd Murad et al. 2017; Maryani et al. 2019); however, to our knowledge, this is the first report of F. sacchari causing postharvest fruit rot disease on M. acuminata ‘Lady Finger’ worldwide; therefore, it needs to be properly managed to preserve marketability.The author(s) declare no conflict of interest.References:Abd Murad, N. B., et al. 2017. J. Appl. Microbiol. 123:1533. https://doi.org/10.1111/jam.13582 Crossref, ISI, Google ScholarGlass, N. L., and Donaldson, G. C. 1995. Appl. Environ. Microbiol. 61:1323. https://doi.org/10.1128/AEM.61.4.1323-1330.1995 Crossref, ISI, Google ScholarLeslie, J. F., and Summerell, B. A. 2006. The Fusarium Laboratory Manual. Blackwell, Ames, IA. https://doi.org/10.1002/9780470278376 Crossref, Google ScholarLeslie, J. F., et al. 2005. Mycologia 97:718. https://doi.org/10.1080/15572536.2006.11832801 Crossref, ISI, Google ScholarMaryani, N., et al. 2019. Stud. Mycol. 92:155. https://doi.org/10.1016/j.simyco.2018.06.003 Crossref, ISI, Google ScholarO’Donnell, K., et al. 1998. Mycologia 90:465. https://doi.org/10.1080/00275514.1998.12026933 Crossref, ISI, Google ScholarThe author(s) declare no conflict of interest.DetailsFiguresLiterature CitedRelated Vol. 104, No. 8 August 2020SubscribeISSN:0191-2917e-ISSN:1943-7692 DownloadCaptionApple scab lesions on h(11) Malus baccata ‘Jackii’ found in 2011 at Skierniewice, Poland (A. Patocchi et al.). Photo credit: A. Patocchi. Healthy `ōhi`a seedling growing from a crack in a lava field (M. A. Hughes et al.). Photo credit: K. Hughes. Metrics Downloaded 1,163 times Article History Issue Date: 28 Jul 2020Published: 3 Jun 2020First Look: 25 Mar 2020Accepted: 25 Mar 2020 Pages: 2290-2290 Information© 2020 The American Phytopathological SocietyKeywordsFusarium saccharipostharvest diseasefruit rotLady Finger bananaThe author(s) declare no conflict of interest.Cited ByThe Genome of Banana Leaf Blight Pathogen Fusarium sacchari str. FS66 Harbors Widespread Gene Transfer From Fusarium oxysporum4 February 2021 | Frontiers in Plant Science, Vol. 12

Phytophthora species hybrids have been repeatedly reported as causing damaging diseases to cultivated and wild plants. Two known hybrids, P. andina and P. × pelgrandis, are pathogens of Solanaceae and ornamentals, respectively, although the extent of their host ranges are unknown. P. andina emerged from hybridization of P. infestans and an unidentified related species, whereas P. × pelgrandis emerged from P. nicotianae and P. cactorum. Considering that hybrids and parental species can coexist in the same regions and to distinguish them usually requires cloning or whole genome sequencing, we aimed to develop a rapid tool to distinguish them. Specifically, we used high-resolution melting (HRM) assays to differentiate genotypes based on their amplicon melting profiles. We designed primers for P. × pelgrandis and parental species based on available sequences of P. nicotianae and P. cactorum nuclear genes containing polymorphisms between species. For P. andina, heterozygous sites from Illumina short reads were used for the same purpose. We identified multiple amplicons exhibiting differences in melting curves between parental species and hybrids. We propose HRM as a rapid method for differentiation of P. andina and P. × pelgrandis hybrids from parental species that could be employed to advance research on these pathogens.

Important damage caused by the fungus Neofusicoccum parvum in thornless blackberry in southern Italy is reported for the first time. The most noticeable symptoms were stem cankers and yellowing of the foliage. Cankers on stems were initially elongated, and infected tissue was darkly pigmented. The fungus was identified based on morphological characteristics and by sequencing the ITS1-5.8S-ITS2 region and part of the translation elongation factor 1-alpha (EF1-a) gene. Pathogenicity tests confirmed that N. parvum caused the disease on blackberry, inducing symptoms similar to those occurring under natural conditions. This is potentially a serious disease of blackberry in southern Italy, where cultivation is expanding.

Two distinct Phytophthora taxa were found to be associated with brown rot of pomelo (Citrus grandis), a new disease of this ancestral Citrus species, in the Vinh Long province, Mekong River Delta area, southern Vietnam. On the basis of morphological characters and using the ITS1-5.8S-ITS2 region of the rDNA and the cytochrome oxidase subunit 1 (COI) as barcode genes, one of the two taxa was provisionally named as Phytophthora sp. prodigiosa, being closely related to but distinct from P. insolita, a species in Phytophthora Clade 9, while the other one, was closely related to but distinct from the Clade 2 species P. meadii and was informally designated as Phytophthora sp. mekongensis. Isolates of P. sp. prodigiosa and P. sp. mekongensis were also obtained from necrotic fibrous roots of Volkamer lemon (C. volkameriana) rootstocks grafted with 'King' mandarin (Citrus nobilis) and from trees of pomelo, respectively, in other provinces of the Mekong River Delta, indicating a widespread occurrence of both Phytophthora species in this citrus-growing area. Koch's postulates were fulfilled via pathogenicity tests on fruits of various Citrus species, including pomelo, grapefruit (Citrus x paradisi), sweet orange (Citrus x sinensis) and bergamot (Citrus x bergamia) as well as on the rootstock of 2-year-old trees of pomelo and sweet orange on 'Carrizo' citrange (C. sinensis 'Washington Navel' x Poncirus trifoliata). This is the first report of a Phytophthora species from Clade 2 other than P. citricola and P. citrophthora as causal agent of fruit brown rot of Citrus worldwide and the first report of P. insolita complex in Vietnam. Results indicate that likely Vietnam is still an unexplored reservoir of Phytophthora diversity.

HomePlant DiseaseVol. 102, No. 3First Report of Root and Basal Stem Rot Caused by Phytophthora cryptogea and P. inundata on Dwarf Banana in Italy PreviousNext DISEASE NOTES OPENOpen Access licenseFirst Report of Root and Basal Stem Rot Caused by Phytophthora cryptogea and P. inundata on Dwarf Banana in ItalyA. Pane, R. Faedda, G. Granata, I. Puglisi, F. Aloi, F. La Spada, M. Evoli, C. Stracquadanio, and S. O. CacciolaA. Pane, R. Faedda, G. Granata, I. Puglisi, F. Aloi, F. La Spada, M. Evoli, C. Stracquadanio, and S. O. Cacciola†Corresponding author: S. O. Cacciola; E-mail: E-mail Address: [email protected]AffiliationsAuthors and Affiliations A. Pane R. Faedda G. Granata I. Puglisi , Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy F. Aloi , Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy, and Department of Agraria, University Mediterranea of Reggio Calabria, Feo di Vito, 89122 Reggio Calabria, Italy F. La Spada , Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy M. Evoli C. Stracquadanio , Department of Agraria, University Mediterranea of Reggio Calabria, Feo di Vito, 89122 Reggio Calabria, Italy, and Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy S. O. Cacciola † , Department of Agriculture, Food and Environment, University of Catania, 95123 Catania, Italy. Published Online:2 Jan 2018https://doi.org/10.1094/PDIS-08-17-1280-PDNAboutSections ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmailWechat In Sicily (southern Italy), local cultivars of dwarf banana (Musa acuminata) are cultivated for edible fruit and as ornamental plants. During the summer of 2015, in an ornamental nursery of Aci San Filippo (Catania province), eastern Sicily, 10 out of 40 mature plants of dwarf banana grown in the field showed leaf chlorosis, wilt, and sudden collapse of the entire plant associated with root and basal stem rot. Two Phytophthora species (overall 24 and 22 isolates, respectively) were consistently recovered directly from rotted roots and stems on BNPRA-HMI selective medium (Masago et al. 1977). Pure cultures of both species were obtained by single-hypha isolations. The first species formed slight petaloid colonies on potato dextrose agar (PDA) and slightly fluffy colonies on V-8 juice agar (V8A). It grew between 2 and 30°C, with an optimum of 25°C. On V8A discs flooded with nonsterile soil extract, this species produced persistent, ovoid to obpyriform, nonpapillate, internally proliferating sporangia (35 to 57 × 22 to 33 µm, mean length/breadth 1.5). In pairings with A1 and A2 reference isolates of P. cryptogea and P. drechsleri, all 24 isolates formed oogonia (diameter 20 to 36 µm), amphigynous antheridia (diameter 7 to 16 µm), and plerotic oospores (diameter 14 to 36 µm) only with the A2 reference isolates. The 22 isolates of the second species formed rosaceous colonies on PDA and stellate colonies on V8A. They grew between 5 and 35°C, with an optimum of 28°C and produced persistent, ovoid to obpyriform, nonpapillate, internally proliferating sporangia (32 to 57 × 48 to 70 µm, mean length/breadth 1.3). These isolates failed to produce gametangia and oospores in single cultures and in pairings with A1 and A2 reference isolates. PCR amplification and sequence analysis of ITS regions of rDNA of the isolates of each species, using ITS 4 and ITS 6 primers (Cooke et al. 2000), revealed 100% similarity between our dwarf banana isolates (GenBank accession nos. KX853521 and KX853523) and several GenBank accessions of P. cryptogea and P. inundata, respectively. Mitochondrial partial COI fragments for cytochrome oxidase subunit 1 (KX853520 and KX853522) amplified according to the method of Robideau et al. (2011), also showed 100% similarity with GenBank accessions of P. cryptogea and P. inundata, respectively. The first species was identified as P. cryptogea (CBS 141725 and CBS 141726) and the second one as P. inundata (CBS 141727 and CBS 141732). Pathogenicity of the deposited isolates of both species was tested separately by transplanting 1-year-old seedlings of dwarf banana (five plants per isolate) in pots filled with infested soil (Salamone et al. 2011). Five control plants were transplanted in pots containing noninfested soil. All plants were maintained in saturated soil for 48 h after transplanting and then grown at 24 to 28°C in greenhouse in natural light/dark cycle and watered once a week. The inoculated plants developed symptoms of root and crown rot within 4 weeks. Control plants remained healthy. P. cryptogea and P. inundata were reisolated solely from symptomatic plants. Reports of infections by Phytophthora spp. on monocots are not frequent (Erwin and Ribeiro 1996); most probably soil waterlogging may have been a predisposing factor. To our knowledge this is the first report of these two Phytophthora species on dwarf banana worldwide.References:Cooke, D. E. L., et al. 2000. Fungal Genet. Biol. 30:17. https://doi.org/10.1006/fgbi.2000.1202 Crossref, ISI, Google ScholarErwin, D. C., and Ribeiro, O. K. 1996. Phytophthora Diseases Worldwide. APS Press, St. Paul, MN. Google ScholarMasago, H., et al. 1977. Phytopathology 67:425. Google ScholarRobideau, G. P., et al. 2011. Mol. Ecol. Resour. 11:1002. https://doi.org/10.1111/j.1755-0998.2011.03041.x Crossref, ISI, Google ScholarSalamone, A., et al. 2011. Plant Dis. 95:358. https://doi.org/10.1094/PDIS-09-10-0659 Link, ISI, Google ScholarDetailsFiguresLiterature CitedRelated Vol. 102, No. 3 March 2018SubscribeISSN:0191-2917e-ISSN:1943-7692 Metrics Article History Issue Date: 19 Feb 2018Published: 2 Jan 2018First Look: 25 Oct 2017Accepted: 20 Oct 2017 Page: 684 Information© 2018 The American Phytopathological SocietyCited byPhytophthora cryptogea (tomato foot rot)CABI Compendium, Vol. CABI CompendiumPhytophthora inundataCABI Compendium, Vol. CABI CompendiumPhytophthora Diversity in a Sentinel Arboretum and in a Nature Reserve Area1 December 2020Diversity and Distribution of Phytophthora Species in Protected Natural Areas in Sicily14 March 2019 | Forests, Vol. 10, No. 3

A metabarcoding method based on genus-specific primers and 454 pyrosequencing was utilized to investigate the genetic diversity of Phytophthora spp. in soil and root samples of potted plants, from eight nurseries. Pyrosequencing enabled the detection of 25 Phytophthora phylotypes distributed in seven different clades and provided a much higher resolution than a corresponding cloning/Sanger sequencing approach. Eleven of these phylotypes, including P. cactorum, P. citricola s.str., P. palmivora, P. palmivora-like, P. megasperma or P. gonapodyides, P. ramorum, and five putative new Phytophthora species phylogenetically related to clades 1, 2, 4, 6, and 7 were detected only with the 454 pyrosequencing approach. We also found an additional 18 novel records of a phylotype in a particular nursery that were not detected with cloning/Sanger sequencing. Several aspects confirmed the reliability of the method: (i) many identical sequence types were identified independently in different nurseries, (ii) most sequence types identified with 454 pyrosequencing were identical to those from the cloning/Sanger sequencing approach and/or perfectly matched GenBank deposited sequences, and (iii) the divergence noted between sequence types of putative new Phytophthora species and all other detected sequences was sufficient to rule out sequencing errors. The proposed method represents a powerful tool to study Phytophthora diversity providing that particular attention is paid to the analysis of 454 pyrosequencing raw read sequences and to the identification of sequence types.

Penicillium polonicum, Altern aria alternata, and Macrophomina phaseolina were identified as causal agents of three different postharvest diseases of cactus pear fruit in southern Italy. P. polonicutn was responsible for blue mould and was identified by sequencing part of the beta-tubulin gene DNA region. A. alternata and M. phaseolina were the causal agents of a dry rot on fruit stored at 5 degrees C and a basal soft rot on fruit stored at 20 degrees C, respectively. The last two fungal species were identified by sequencing the GAPDH and TEF1-alpha gene regions.

Pomegranate (Punica granatum L.) has become a commercial fruit crop in southern Italy during the last years. In 2013, the specialized pomegranate cultivation extended over 130 ha. Leading producing regions are Apulia and Sicily, southern Italy. Two types of rot of mature pomegranate fruit have been detected in Sicily, heart rot and soft rot. Heart rot, which is also known as black rot, was found on fruit of the cultivar 'Wonderful' and consisted in an internal decay of the arils, usually confined to part of the fruit compartments, while the rind remained unaffected. The causal agent of this disease was identified as Alternaria alternata (Fr) Keissl on the basis of morphological traits as well as of sequencing of the ITS and TEF1-alpha gene regions. Soft rot was observed on mature fruit of 'Mollar de Elche' after dryness periods followed by intense rains. Several species of Alternaria, Aspergillus, Botrytis, Penicillium and Rhizopus genera were isolated from infected fruit but no one was consistently associated with the disease. By contrast, a close relationship was found between the occurrence of soft rot and the attacks of Mediterranean fly or other insects invading the mesocarp.

The objective of this study was to investigate the health conditions of oak and beech stands in the three Regional Parks of Sicily (Etna, Madonie and Nebrodi). A total of 81 sampling areas were investigated, 54 in oak stands and 27 in beech stands. The phytosanitary conditions of each tree within the respective sampling area was expressed with a synthetic index namely phytosanitary class (PC). Oak stands showed severe symptoms of decline, with 85% of the sampling areas including symptomatic trees. In general, beech stands were in better condition, with the exception of Nebrodi Park, where trees showed severe symptoms of decline. On oak trees, infections of fungal pathogens were also observed, including Biscogniauxia mediterranea, Polyporus sp., Fistulina hepatica, Mycrosphaera alphitoides and Armillaria sp. By contrast, on beech trees Biscogniauxia nummularia, Fomes fomentarius and Neonectria radicicola were recognized. Furthermore, twenty-two permanent sampling areas were delimited with the aim of monitoring regularly the health conditions of forests in these three parks.