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Highbush blueberry is an increasingly important crop due to its economic value and demonstrated health benefits of blueberries. Leaf spots are considered as minor diseases of blueberry plants, but they adversely affect blueberry productivity, causing reduced photosynthetic activity, flower bud formation and berry production. Surveys of blueberry crops were conducted in Piedmont, Northern Italy, during 2019-2020. Fungi isolated from leaf spots of the blueberry cultivar ‘Blue Ribbon’ were identified as Colletotrichum helleniense through a robust multi-locus phylogeny. Eight genomic loci were considered: tub, gapdh, act, cal, his3, chs-1, ApMat and gs. Morphological characters of a representative strain were assessed. Pathogenicity was confirmed on four blueberry cultivars, although with different levels of aggressiveness to the cultivars. This study shows the importance of a polyphasic approach to investigate species of Colletotrichum, and the relevance of molecular tools for the species-level characterization within the ‘Kahawae’ clade. This is the first report of Colletotrichum helleniense causing leaf anthracnose on Vaccinium corymbosum.

The genera Paramyrothecium and Albifimbria have been established from the former genus Myrothecium and they generally comprise common soil-inhabiting and saprophytic fungi. Within these genera, only two fungi have been recognized as phytopathogenic thus far: P. roridum and A. verrucaria, both of which cause necrotic leaf spots and plant collapse. Severe leaf necrosis and plant decay have been observed in Northern and Southern Italy on leafy vegetable crops. Thirty-six strains of Paramyrothecium- and Albifimbria-like fungi were isolated from affected plants belonging to eight different species. Based on morphological characteristics, 19 strains were assigned to A. verrucaria, whereas the remaining strains, which mostly resembled Paramyrothecium-like fungi, could not be identified precisely. Molecular characterization of six loci (internal transcribed spacer [ITS], β-tubulin [tub2], calmodulin [cmdA], translation elongation factor 1-alpha [tef1], large subunit ribosomal RNA [LSU], and mitochondrial ATP 6synthase 6 [ATP6]) of the 36 new isolates and three previously ITS-characterized isolates assigned all strains to four species: A. verrucaria, P. roridum, P. foliicola, and P. nigrum. Single and concatenated phylogenetic analyses were conducted, and they clearly distinguished the isolated fungi into four different groups. A. verrucaria, P. roridum, P. foliicola, and P. nigrum were able to induce leaf necrosis singly, and they were confirmed to be the causal agents of the leaf spot disease through pathogenicity assays. The involvement of fungi previously considered saprophytic (i.e., P. foliicola and P. nigrum) in the development of plant disease for the first time deserves particular attention because of the possibility of their transmission by seeds and the limited knowledge of their management with chemicals.

This study represents the first survey studying the occurrence, genetic diversity, and pathogenicity of Botryosphaeriaceae species associated with symptomatic citrus species in citrus-production areas in five European countries. Based on morphological features and phylogenetic analyses of internal transcribed spacer (ITS) of nuclear ribosomal DNA (nrDNA), translation elongation factor 1-alpha (TEF1) and β-tubulin (TUB2) genes, nine species were identified as belonging to the genera Diplodia, Dothiorella, Lasiodiplodia, and Neofusicoccum. Isolates of Neofusicoccum parvum and Diplodia pseudoseriata were the most frequently detected, while Dothiorella viticola had the widest distribution, occurring in four of the five countries sampled. Representative isolates of the nine Botryosphaeriaceae species used in the pathogenicity tests caused similar symptoms to those observed in nature. Isolates assayed were all re-isolated, thereby fulfilling Koch’s postulates. Isolates of Diplodia pseudoseriata and Diplodia olivarum are recorded for the first time on citrus and all species found in our study, except N. parvum, are reported for the first time on citrus in Europe.

The importance and sad fame of Claviceps purpurea, a fungus that attacks rye, are linked to the disastrous consequences for human and animal health caused by the presence of its sclerotia in the flours and fodder.

Twelve trials, in closed soilless culture under controlled conditions, were carried out to evaluate the efficacy of resistance inducers (based on K-phosphite and K-silicate used alone or in combination), and of experimental biocontrol agents (Trichoderma sp. TW2, a mixture of Pseudomonas FC 7B, FC 8B, and FC 9B, Fusarium solani FUS25, Pseudomonas sp. PB26), and a commercial formulation of Trichoderma gamsii + T. asperellum, against diseases caused by Phytophthora capsici of sweet pepper. The products were applied using three different protocols, and effects on incidence of Phytophthora crown, stem and root rots (% dead plants), disease development (area under the disease progress curve; AUDPC), and plant fresh weights were evaluated. Potassium phosphite, applied directly at standard P2O5:K2O, 1.30 + 1.05 g L-1) and at half standard rates, onto growing media, or via nutrient solution, and before infestation of peat plant growing medium with P. capsici, provided the best disease management in a dose-dependent manner, with an 80% reduction of Phytophthora crown, stem and root rots for the standard dosage and for both types of application. These treatments also reduced proportions of dead plants by 47% from the standard rate and by 62% at the half standard rate, when applied via the nutrient solution or directly to the substrate. K-silicate alone partially reduced the percentage of dead plants, with efficacy of 20–23%. No improvement in disease control was observed when K-silicate was applied in combination with phosphite, while K-silicate alone or combined with K-phosphite reduced disease development, compared to untreated controls. Biocontrol agents (BCAs), applied preventively, reduced Phytophthora crown, stem and root rots, with similar or better results than those from the commercial mixture of Trichoderma asperellum + T. gamsii. Among the tested BCAs, Fusarium solani FUS25 provided the most consistent disease reduction (60–65%) and gave increased plant fresh weights. All the tested BCAs reduced disease development, with a similar trend for different disease pressures. The least AUDPC values, compared to the non-treated controls, were from Fusarium solani FUS25, followed by the tested Pseudomonas strains and Trichoderma sp. TW2. These results indicate the potential for potassium phosphite and biocontrol agents in management of Phytophthora crown, stem and root rots of pepper grown in soilless systems.

Mistletoe (Viscum album) is an evergreen epiphitic plant parasite of several species of trees, such as poplars, oak, lindens, elms and pines, from which it draws water and nutrients. It is able to perform photosynthesis (hence the green colour), but needs other plants’ contribution for its growth.

This grapevine disease is caused by a phytoplasma (a bacterium with no cell wall) transmitted by a leafhopper, Scaphoideus titanus, native to North America, introduced by accident to France after 1950 at a latitude around the 43rd parallel.

The behaviour of Myrothecium roridum, artificially inoculated on cultivated rocket (Eruca sativa), has been evaluated under eight different temperature and CO2 concentration combinations (from 14-18 °C to 26-30 °C and with 400-450 or 800-850 ppm of CO2). The pathogen isolate used for this study was inoculated on rocket and disease severity increased with high temperatures for both CO2 levels. Verrucarin A and roridin E mycotoxins were produced under all the tested temperatures at high CO2 conditions. The maximum level of verrucarin A was found at 14-18 °C and 800-850 ppm of CO2, and the maximum roridin E production was detected at 26-30 °C with 800-850 ppm of CO2. The results obtained in this study show that both the CO2 concentration and the temperature influence disease severity and mycotoxin production in different ways. An increase in temperature, which is favourable for attacks of the pathogen, could induce the spread of M. roridum in temperate regions, and this pathogen could take on even greater importance in the future, considering its ability to produce mycotoxins.

Grapevine may be affected simultaneously by several pathogens whose complex interplay is largely unknown. We studied the effects of infection by two grapevine viruses on powdery mildew and downy mildew development and the molecular modifications induced in grapevines by their multiple interactions. Grapevine fanleaf virus (GFLV) and grapevine rupestris stem pitting-associated virus (GRSPaV) were transmitted by in vitro-grafting to Vitis vinifera cv Nebbiolo and Chardonnay virus-free plantlets regenerated by somatic embryogenesis. Grapevines were then artificially inoculated in the greenhouse with either Plasmopara viticola or Erysiphe necator spores. GFLV-infected plants showed a reduction in severity of the diseases caused by powdery and downy mildews in comparison to virus-free plants. GFLV induced the overexpression of stilbene synthase genes, pathogenesis-related proteins, and influenced the genes involved in carbohydrate metabolism in grapevine. These transcriptional changes suggest improved innate plant immunity, which makes the GFLV-infected grapevines less susceptible to other biotic attacks. This, however, cannot be extrapolated to GRSPaV as it was unable to promote protection against the fungal/oomycete pathogens. In these multiple interactions, the grapevine genotype seemed to have a crucial role: in ‘Nebbiolo’, the virus-induced molecular changes were different from those observed in ‘Chardonnay’, suggesting that different metabolic pathways may be involved in protection against fungal/oomycete pathogens. These results indicate that complex interactions do exist between grapevine and its different pathogens and represent the first study on a topic that still is largely unexplored.

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 &beta, 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.

Species of Colletotrichum are considered important plant pathogens, saprobes, and endophytes on a wide range of host plants. In Italy, several Colletotrichum species have been reported in glasshouse environments. In this study, we have explored the occurrence, diversity, and pathogenicity of Colletotrichum spp. associated with aromatic and ornamental plants belonging to the Lamiaceae family. Surveys were carried out during the 2011−2018 period in Liguria and Piedmont, Italy. A total of 19 Colletotrichum isolates were collected from symptomatic leaves and seeds of Ocimum basilicum (basil), Origanum vulgare (oregano) and different Salvia spp. A multi-locus phylogeny was established based on the basis of four genomic loci (ITS, GAPDH, ACT and TUB2). The aggressiveness of selected, representative isolates were tested. Colletotrichum isolates were identified as being members of three major species complexes: C. acutatum, C. destructivum, and C. gloeosporioides. Colletotrichum fioriniae, C. bryonicola, and C. fructicola were found in association with leaf lesions on Salvia leucantha, S. nemorosa, and S. greggii, respectively. Colletotrichum nigrum was isolated from twig lesions of S. greggii. Moreover, C. fioriniae and C. ocimi were found to be responsible for causing leaf anthracnose of oregano and basil, respectively. All the tested isolates were pathogenic and reproduced identical symptoms to those observed in commercial glasshouses. The present study improves our understanding of Colletotrichum species associated with several hosts belonging to the Lamiaceae family, which are cultivated extensively throughout Italy for different purpose, and provides information that may be useful for an effective disease management program.

Cineraria maritima L. (synonym Senecio cineraria DC.), commonly known as dusty-miller, is grown in Italy for landscape use in parks and gardens. In the spring of 2001, severe outbreaks of a previously unknown disease were observed in commercial farms located in northern Italy. Leaves of infected plants showed several sori on the abaxial surface, progressing to the adaxial surface, and often in the interveinal areas. On the adaxial surface of leaves, chlorotic areas developed and eventually turned brown. Severely infected leaves wilted, but remained attached to the stem. Signs of the fungus were present as whitish and catenulate sporangia emerging from the sori. Sporangia, organized in chains, had an average diameter of 20.5 × 26.5 μm. On the basis of the microscopic observations, the causal agent of the disease was identified as Albugo tragopogonis. Pathogenicity was confirmed by inoculating leaves of healthy C. maritima plants with a sporangial suspension (5 × 102 sporangia per ml) obtained from infected plants. Noninoculated plants served as a control. Plants were kept covered with plastic bags for 72 h and maintained at 15°C. After 10 days, typical symptoms of white rust developed on inoculated plants starting from the basal leaves. Within 30 days, affected leaves were completely wilted. Microscopic examination of sporangia within sori verified the pathogen to be A. tragopogonis. No symptoms developed on the control plants. A. tragopogonis has been reported as the causal agent of white rust on several species belonging to the genus Senecio in the United States (1). In New Zealand, the presence of A. tragopogonis was reported on the genus Cineraria in 1959 (2). To our knowledge, this is the first report of the presence of white rust on Cineraria maritima in Italy. References: (1) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society, St Paul, MN, 1989. (2) J. M. Dingley. N. Z. J. Agric. Res. 2:380, 1959.

Lamium galeobdolon L. (Labiatae) is a common ornamental species that grows in shade areas and often used as a ground cover in gardens. During the summer of 2006, severe outbreaks of a previously unknown powdery mildew were observed on all Lamium spp. plants in some gardens near Biella (northern Italy). Both surfaces of the leaves of affected plants were covered with dense, white mycelia and conidia. As the disease progressed, infected leaves turned yellow and died. Mycelia and conidia also were observed on stems and flowers. Conidia were hyaline, ellipsoid, borne in short chains (with a maximum of five conidia per chain), and measured 29 to 37 × 16 to 20 μm (average 33 × 18 μm). Conidiophores, 91 to 104 μm (average 96 μm) long, showed the foot cell measuring 28 to 49 × 9 to 11 μm (average 38 × 10 μm), followed by three shorter cells measuring 14 to 26 × 9 to 15 μm (average 21 × 11 μm). Fibrosin bodies were absent. Chasmothecia were not observed in the collected samples. The internal transcribed spacer region (ITS) of rDNA was amplified using the primers ITS4/ITS6 (4) and sequenced. BLASTn analysis (1) of the 436 bp obtained showed an E-value of 0.0 with Golovinomyces orontii (Erysiphe orontii.) (3). The nucleotide sequence has been assigned GenBank Accession No. EF 121871. Inoculations were made by gently pressing diseased leaves onto leaves of five healthy L. galeobdolon plants. Five noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a greenhouse at temperatures between 15 and 28°C. After 10 days, typical powdery mildew colonies developed on inoculated plants. Noninoculated plants did not show symptoms. The pathogenicity test was carried out twice. To our knowledge, this is the first report of the presence of powdery mildew on L. galeobdolon caused by G. orontii in Italy. Blumer (2) was able to reproduce powdery mildew symptoms on L. galeobdolon using populations from cucumber, while Braun (3) reported L. galeobdolon as a possible host of E. orontii. Herbarium specimens of this disease are available at AGROINNOVA Collection, University of Torino, Italy. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) S. Blumer. Ber. Schweiz. Bot. Ges. 62:384, 1952. (3) U. Braun. A Monograph of the Erysiphaceae (Powdery Mildews). Cramer, Berlin, GDR, 1987. (4) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997.

Penstemon barbatus (Cav.) Roth (synonym Chelone barbata), used in parks and gardens and sometimes grown in pots, is a plant belonging to the Scrophulariaceae family. During the summers of 2004 and 2005, symptoms of a root rot were observed in some private gardens located in Biella Province (northern Italy). The first symptoms resulted in stunting, leaf discoloration followed by wilt, root and crown rot, and eventually, plant death. The diseased tissue was disinfested for 1 min in 1% NaOCl and plated on a semiselective medium for Oomycetes (4). The microorganism consistently isolated from infected tissues, grown on V8 agar at 22°C, produced hyphae with a diameter ranging from 4.7 to 5.2 μm. Sporangia were papillate, hyaline, measuring 43.3 to 54.4 × 26.7 to 27.7 μm (average 47.8 × 27.4 μm). The papilla measured from 8.8 to 10.9 μm. These characteristics were indicative of a Phytophthora species. The ITS region (internal transcribed spacer) of rDNA was amplified using primers ITS4/ITS6 (3) and sequenced. BLASTn analysis (1) of the 800 bp obtained showed a 100% homology with Phytophthora citrophthora (R. & E. Sm.) Leonian. The nucleotide sequence has been assigned GenBank Accession No. DQ384611. For pathogenicity tests, the inoculum of P. citrophthora was prepared by growing the pathogen on autoclaved wheat and hemp kernels (2:1) at 25°C for 20 days. Healthy plants of P. barbatus cv. Nano Rondo, 6 months old, were grown in 3-liter pots (one plant per pot) using a steam disinfested substrate (peat/pomix/pine bark/clay 5:2:2:1) in which 200 g of kernels per liter of substrate were mixed. Noninoculated plants served as control treatments. Three replicates were used. Plants were maintained at 15 to 20°C in a glasshouse. The first symptoms, similar to those observed in the gardens, developed 21 days after inoculation, and P. citrophthora was consistently reisolated from infected plants. Noninoculated plants remained healthy. The pathogenicity test was carried out twice with similar results. A nonspecified root and crown rot of Penstemon spp. has been reported in the United States. (2). To our knowledge, this is the first report of P. citrophthora on P. barbatus in Italy as well as in Europe. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997 (2) F. E. Brooks and D. M. Ferrin. Plant Dis. 79:212, 1995. (3) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (4) H. Masago et al. Phytopathology 67:425, 1977.

Lupinus polyphyllus Lindl., a perennial ornamental belonging to the Leguminosae family, is grown in gardens for flower beds and borders. During the summer of 2006, in several gardens located in the Biella Province (northern Italy), a new wilt of Lupine was observed in 20 to 30% of the plants. The vascular tissue in stems of affected plants appeared brown. These plants were stunted and developed yellow leaves with brown or black streaks in the vascular tissue. Verticillium dahliae was consistently isolated from symptomatic vascular tissue and leaves when cultured on potato dextrose agar (PDA) (3). Microscopic observations revealed hyaline hyphae, with many irregular, dark microsclerotia, ranging from 17 to 61 μm. Conidiophores showed two verticils of three elements. Conidia were hyaline, elliptical, single-celled, measuring 3.4 to 6.0 × 1.8 to 3.1 μm (average 4.5 × 2.4 μm). The ITS region (internal transcribed spacer) of rDNA was amplified using the primers ITS4/ITS6 (2) and sequenced. BLASTn analysis (1) of the 521 bp obtained showed an E-value of 0.0 with V. dahliae. The nucleotide sequence has been assigned GenBank Accession No. EF015891. Healthy 30-day-old plants (10 per treatment) of L. polyphyllus were inoculated by root dip with a conidial suspension (0.5 × 106 CFU/ml) of V. dahliae isolated from infected plants. Ten noninoculated plants served as control treatments. All plants were transplanted into pots filled with a mix of sphagnum peat/pomix/pine bark/clay (50:20:20:10) and grown outdoors at temperatures ranging from 15 to 25°C. First wilt symptoms and vascular discoloration in the roots, crown, and veins developed within 20 days on each inoculated plant and become evident after 50 days. V. dahliae was consistently reisolated from infected plants. Noninoculated plants remained healthy. The pathogenicity test was conducted twice. To our knowledge, this is the first report of V. dahliae on L. polyphyllus in Italy. A wilt caused by V. dahliae on L. polyphyllus was observed in the Netherlands in 1925 (4). References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (3) G. F. Pegg and B. L. Brady. Verticillium Wilts. CABI Publishing, Wallingford, UK, 2002. (4) J. H. H. Van der Meer. Meded. Landbouwhogesch. Wagening. 28, 1925.

In the winter of 2007 in Piedmont (northern Italy), symptoms of a previously unknown disease were observed on beet (Beta vulgaris L. subsp. vulgaris) (garden beet group) grown under a tunnel on several commercial farms near Cuneo. First symptoms appeared on 1-month-old plants, occurring as brown, round-to-oval spots as much as 2 cm in diameter with dark concentric rings near the perimeter. Small, dark pycnidia were present throughout the spots in concentric rings. Generally, older, lower leaves were affected more than the younger ones. Ten to fifteen percent of the plants were affected. Symptoms on the roots began near the crown as small, dark, sunken spots that became soft and water soaked. Eventually, spots on the roots turned dark brown to black and black lines separated diseased and healthy tissues. Older infected tissues were black, dry, shrunken, and spongy. Pycnidia were not observed on affected roots. From infected leaves and roots, a fungus was consistently isolated on potato dextrose agar (PDA) amended with 25 mg/l of streptomycin. The fungus was grown on PDA and maintained at 22°C (12 h of light, 12 h of dark). After 10 days, black pycnidia (130 to 328 [204] μm in diameter) developed, releasing abundant hyaline, elliptical, nonseptate conidia measuring 3.9 to 6.7 (5.1) × 2.4 to 5.9 (3.6) μm. On the basis of its morphological characteristics, the fungus was identified as a Phoma sp. (1). The internal transcribed spacer (ITS) region was amplified using primers ITS4/ITS6 (2) and sequenced. BLASTn analysis of the 557 bp obtained showed an E-value of 0.0 with Phoma betae. The nucleotide sequence has been assigned GenBank Accession No. EU003450. Pathogenicity tests were performed by spraying leaves of healthy 20-day-old potted B. vulgaris plants with a spore and mycelial suspension (1 × 106 spores or mycelial fragments per ml). Noninoculated plants sprayed only with water served as controls. Fifteen plants (three per pot) were used for each treatment. Plants were covered with plastic bags for 5 days after inoculation and kept in a growth chamber at 20°C. Symptoms previously described developed on leaves of all inoculated plants 5 days after inoculation, while control plants remained healthy. Later, pycnidia and conidia, with the same dimensions and characteristics previously described, were observed on the infected leaves. The fungus was consistently reisolated from the lesions of the inoculated plants. The pathogenicity test was carried out twice. P. betae on B. vulgaris var. cycla has been reported in Canada (3) as well as in other countries. The same pathogen was reported in Italy on sugar beet (2). References: (1) G. H. Boerema and G. J. Bollen. Persoonia 8:111, 1975. (2) A. Canova. Inf. Fitopatol. 16:207, 1966. (3) D. E L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (4) J. R. Howard et al. Diseases of Vegetable Crops in Canada. Canadian Phytopathological Society, 1994.

Camellia cultivation has a long history in the Lake Maggiore area of northern Italy where a wide selection of varieties is present. Camellias are appreciated for their large, colorful flowers that bloom from late fall through early spring. In July 2005, a previously unknown foliar disease was observed on a collection of 2- to 12-month-old camellia cultivars (Camellia japonica) grown in several nurseries located in the Verbania Province (northern Italy). The disease was observed on plants grown in pots (10 to 24 cm in diameter) that were maintained either in the open or in a greenhouse and was present for the entire growing season. However, symptoms were more severe during the summer with temperatures ranging between 25 and 30°C with high relative humidity values. During the months of June and July of 2005, severe attacks involving as much as 70% of plants were observed on C. japonica cvs. Mrs. Tingley, Burnside, Hagoromo (synonym Magnoliaeflora), and Giuseppe Traverso. The disease was again observed in 2006. On the upper side of the younger leaves, small necrotic spots (3 to 8 mm in diameter) initially developed mainly at the margin of the leaves and near the petioles. Necrotic areas were surrounded by a chlorotic halo that turned progressively black. The necrotic areas often coalesced, generating larger spots with a diameter ranging from 15 to 30 mm. Severely affected plants were defoliated. Infected plants sometimes died. The presence of lesions on mature plants decreased aesthetic quality and market value. Leaf spots contained dark brown, multicellular, pyriform conidia. Conidia, generally in short chains, were 20.5 to 34.8 μm (average 29.3 μm) long, 6.9 to 12.2 μm (average 9.9 μm) wide, with 3 to 4 longitudinal cross walls, and an average of 5.7 single cells. From 15 samples of infected leaves, several isolates of a fungus identified on the basis of its morphological characteristics as belonging to the Alternaria alternata complex (2) were consistently isolated on potato dextrose agar containing 25 mg/l of streptomycin sulfate. Pathogenicity tests were performed by spraying leaves of healthy 6-month-old potted C. japonica cv. Burnside plants with a spore and mycelial suspension (1 × 105 CFU/ml) prepared by using a mixture of three isolates obtained in 2005 grown on PDA for 30 days at 23 ± 2°C in a growth chamber (12 h of light per day). Plants without inoculation served as a control. Five plants were used for each treatment. Plants were covered with plastic bags for 3 days after inoculation and maintained at 25°C in growth chambers. The first lesions developed on leaves 3 days after inoculation, while control plants remained healthy. Sixty days after artificial inoculation, 25% of the inoculated plants were dead, while the control plants remained healthy. From lesions of infected plants, a fungus belonging to the A. alternata complex was consistently reisolated. The pathogenicity test was carried out twice. The presence of A. alternata on C. sinensis, the commercial tea plant, was reported in India (1). Previously, a flower blight caused by A. tenuis was reported in the United States (3). This is, to our knowledge, the first report of A. alternata on C. japonica in Italy and probably in the world. The disease was present in 2005 and 2006 in several commercial nurseries affecting 50% of plants of susceptible cultivars. References: (1) B. N. Chakraborty et al. Plant Pathol. 55:303, 2006. (2) E. G. Simmons. Pages 1–35 in: Alternaria Biology, Plant Diseases and Metabolites. J. Chelchowski and A. Visconti, eds. Elsevier, Amsterdam, 1992. (3) A. J. Watson. Plant Dis. Rep. 34:186, 1950.

Paris daisy (Argyranthemum frutescens), also known as Marguerite daisy, is an economically important crop in the Riviera Ligure (northern Italy) where approximately 18 million potted plants per year are produced for export. During the fall and winter of 2007, Paris daisy ‘Bright Carmen’ plants, started in a greenhouse and growing outside in a commercial nursery at Albenga, showed a previously unknown powdery mildew. Young stems, particularly in the interior portions of the plant, were covered with a white mycelium. As the disease progressed, leaves became covered with the mycelium, resulting in smaller, chlorotic leaves. Conidia were hyaline, cylindrical, borne in chains (two to three conidia per chain) and measured 30 × 12 μm (20 to 34 × 10 to 15 μm). Conidia were generated by conidiophores represented by a foot cell measuring 55 to 101 × 11 to 12 μm followed by two shorter cells measuring 19 to 29 × 11 to 14 and 24 to 33 × 12 to 14 μm. Fibrosin bodies were absent. Chasmothecia were not observed in the collected samples. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 441 bp showed a 100% homology with the sequence of Golovinomyces cichoracearum (= Erysiphe cichoracearum) (3). The nucleotide sequence has been assigned GenBank Accession No. EU486992. Pathogenicity was confirmed through inoculation by gently pressing diseased leaves onto leaves of healthy Paris daisy plants of cvs. Blazer Rose, Bright Carmine, Cherry Harmony, Crowned Rose, Fulvia, Sole Mio, Stella 2000, Summit Pink, and Sun Light. Three plants per cultivar were inoculated, while the same number served as noninoculated controls. The pathogenicity test was carried out twice. Plants were maintained in a greenhouse at temperatures ranging from 15 to 21°C. Fifteen days after inoculation, typical symptoms of powdery mildew developed on inoculated plants of all cultivars, with the exception of Stella 2000. The fungus observed on inoculated plants was morphologically identical to that originally observed. Noninoculated plants did not show symptoms. To our knowledge, this is the first report of powdery mildew on A. frutescens in Italy. G. cichoracearum has been reported on Chrysanthemum frutescens in Switzerland (2). The economic impact of this disease is limited but can easily increase because of the intensive cultivation of this crop. The availability of resistant or partially resistant cultivars will help reduce the impact of this new disease. Voucher specimens are available at the AGROINNOVA Collection, University of Torino. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) A. Bolay, Cryptogam. Helv. 20:1, 2005. (3) U. Braun and S. Takamatsu. Schlechtendalia 4:1, 2000.

Rudbeckia fulgida (common name orange coneflower) is an herbaceous perennial (Asteraceae) grown in full sun in perennial borders in gardens. At the end of the summer of 2007, in a public garden located in Turin (northern Italy), symptoms of vascular wilt and stunting were observed on approximately 80% of the plants grown in a mixed border. Initial symptoms were yellowing of external leaves and brown or black streaks in the vascular tissue of roots, crown, and leaves. A fungus was consistently and readily isolated on potato dextrose agar from symptomatic vascular tissue previously disinfested in 1% sodium hypochloride. Ovoid, dark microsclerotia, 41 to 108 μm, developed in hyaline hyphae after 10 days of growth at 23°C (12 h of light and 12 h of dark). Hyaline, elliptical, single-celled conidia, 3.2 to 7.3 × 2.1 to 3.7 (average 4.7 × 2.8) μm, developed on verticillate conidiophores. On the basis of these morphological characteristics, the fungus was identified as Verticillium dahliae (4). The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 530 bp showed a 100% homology with the sequence of V. dahliae. The nucleotide sequence has been assigned GenBank Accession No. EU 627007. Healthy, 30-day-old R. fulgida plants were grown in a steam-disinfested mix of sphagnum peat:pomix:pine bark:clay (50:20:20:10) infested with a conidial suspension (1.5 × 106/ml) of three isolates of V. dahliae isolated from infected plants. Noninoculated plants served as controls. Plants (16 per treatment) were grown in pots (3 liter vol) and maintained in a glasshouse at temperatures between 22 and 25°C and relative humidity between 50 and 70%. First wilt symptoms and vascular discoloration in the roots, crown, and veins developed 17 days after inoculation. Noninoculated plants remained healthy. The pathogenicity tests were carried out twice. To our knowledge, this is the first report in Italy of Verticillium wilt on R. fulgida. Wilts caused by V. dahliae on R. laciniata in Poland (3) and V. albo-atrum on R. hirta in the United States (2) were previously reported. The importance and economic impact of this disease is currently limited but may increase because of the popularity of Rudbeckia spp. in private and public parks. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. F. Farr et al. Fungi on Plants and Their Products in the United States. The American Phytopathological Society, St Paul, MN, 1989. (3) B. Leski. Rocz. Nauk Roln. 253, 1974. (4) G. F. Pegg and B. L. Brady. Verticillium Wilts. CABI Publishing, Wallingford, UK, 2002.

Paris daisy (Argyranthemum frutescens (L.) Sch. Bip.) is an economically important crop on the Riviera Ligure (northern Italy), where approximately 10 million plants per year are produced for export. In the winter of 2007, extensive wilting was observed on 5-month-old potted plants of A. frutescens grown in a commercial greenhouse near Albenga. First symptoms included stem necrosis, darkening and withering of leaves, and wilting of young buds. As stem and foliar necrosis progressed, infected plants wilted and died. Wilt occurred a few days after the appearance of the first symptoms. Infected plants were characterized by the presence of soft, watery tissues. Lesions became covered with a whitish mycelium and dark sclerotia were produced on the mycelium. Diseased stem tissue was surface sterilized for 1 min in 1% NaOCl and plated on potato dextrose agar (PDA) amended with 100 mg/l streptomycin sulfate. Sclerotinia sclerotiorum (Lib.) de Bary (2) was consistently recovered from infected stem pieces. Sclerotia produced on PDA measured 1.4 to 5.2 × 2.3 to 6.7 (average 3.3 to 4.2) mm. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and then sequenced. BLAST analysis (1) of the 531-bp segment showed a 100% homology with the sequence of S. sclerotiorum. The nucleotide sequence has been assigned GenBank Accession No. EU 556701. Pathogenicity of two isolates obtained from infected plants was confirmed by inoculating 10 90-day-old plants for each isolate. Plants were grown singly in 18-cm-diameter pots maintained in a greenhouse under shade and were regularly irrigated and fertilized. Mycelium plugs 1 cm2 were excised from a 10-day-old PDA culture of both isolates and placed on the soil surface around the base of each plant. Ten noninoculated plants served as controls. Plants were maintained in a greenhouse under shade at temperatures ranging between 6 and 22°C (average 18°C) and relative humidity at >90%. The inoculation trial was carried out twice. All inoculated plants developed leaf yellowing by 22 days after inoculation. White, cottony mycelium and black sclerotia developed on stems and at the base of all inoculated plants. Eventually, infected plants wilted. Control plants remained symptomless. S. sclerotiorum was reisolated from the stems of inoculated plants. To our knowledge, this is the first report of S. sclerotiorum causing white mold on A. frutescens in Italy as well as worldwide. The economic importance of this disease can be considered limited at the moment. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997 (2) N. F. Buchwald. Kongl. Veterisk Landb. Aarssk. 75, 1949.

Lampranthus sp. N.B. Brown (figmarigold) of the Aizoaceae family is used as groundcover in gardens. In October of 2008, severe outbreaks of a previously unknown rot were observed in a nursery located in Liguria, near Savona (northern Italy), on 35-day-old rooted cuttings grown in a peat substrate. Approximately 50% of rooted cuttings of red-flowered cultivars were affected. Lesions on collars and young stems were brown, water soaked, and soft. Plants eventually collapsed as roots rotted. Thin, aerial hyphae were visible on the surface of the stems and substrate. Later, a thick, light yellow, mycelial mat surrounded infected plants. Tissue fragments were excised from the margins of the lesions, dipped in a solution containing 1% sodium hypochlorite, and plated on potato dextrose agar and a medium selective for Oomycetes (4). Plates were incubated under constant fluorescent light at 23 ± 1°C for 4 to 5 days. Hyphae of five isolates grown on V8 medium were aseptate and 4.2 to 7.9 (average 6.2) μm wide. Sporangia consisted of complexes of swollen hyphal branches. Oogonia were globose, smooth, and 23.5 to 28.0 (average 25.9) μm in diameter. Antheridia were barrel shaped, intercalary, and diclinous. Oospores were globose and 19.4 to 23.6 (average 21.4) μm in diameter. The internal transcribed spacer (ITS) region of rDNA of a single isolate (DB24112008) was amplified with primers ITS4/ITS6 and sequenced. A BLAST analysis (1) in GenBank of the 1,074-bp segment showed a 100% homology with the sequence of Pythium aphanidermatum (Accession No. EU245039). The nucleotide sequence has been assigned the GenBank Accession No. FJ492745. Pathogenicity tests were performed twice on a red-flower cultivar of a Lampranthus sp. grown in 1-liter pots containing a peat moss substrate infested with wheat and hemp kernels colonized with one isolate of P. aphanidermatum at a rate of 20 g/liter. Ten plants were grown in infested media and 10 plants were grown in noninfested media. Greenhouse temperatures were 18 to 24°C. The first symptoms of stem and root rot developed 15 days later, while control plants remained healthy. P. aphanidermatum was consistently reisolated from the lesions. To our knowledge, this is the first report of P. aphanidermatum on a Lampranthus sp. in Italy. The disease has been reported in Japan (3) in 2008, while in the United States, a Pythium sp. was reported on L. aureus and L. glomeratus (2). Currently, the economic importance of Pythium rot on figmarigold in Italy is still limited. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. F. Farr et al. Fungi on Plants and Products in the United States. The American Phytopathological Society, St Paul, MN, 1989. (3) H. Kawarazachi et al. J. Gen. Plant Pathol. 74:94, 2008. (4) H. Masago et al. Phytopathology, 67, 425, 1977.

Aquilegia flabellata (Ranunculaceae), fan columbine, is a perennial herbaceous plant with brilliant blue-purple flowers with white petal tips. It can also be grown for cut flower production. In April of 2008, in several nurseries located near Biella (northern Italy), a leaf blight was observed on 10 to 15% of potted 30-day-old plants grown on a sphagnum peat substrate at 15 to 20°C and relative humidity of 80 to 90%. Semicircular, water-soaked lesions developed on leaves just above the soil line at the leaf-petiole junction and later along the leaf margins. Lesions expanded over several days along the midvein until the entire leaf was destroyed. Blighted leaves turned brown, withered, and abscised. Severely infected plants died. Diseased tissue was disinfested for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 25 mg/liter streptomycin sulfate. A fungus with the morphological characteristics of Rhizoctonia solani was consistently recovered, then transferred and maintained in pure culture. Ten-day-old mycelium grown on PDA at 22 ± 1°C appeared light brown, rather compact, and had radial growth. Sclerotia were not present. Isolates obtained from affected plants successfully anastomosed with tester isolate AG 4 (AG 4 RT 31, obtained from tobacco plants). Results were consistent with other reports on anastomosis reactions (2). Pairings were also made with tester isolates of AG 1, 2.1, 2.2, 3, 6, 7, 11, and BI with no anastomoses observed between the recovered and tester isolates. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 648-bp fragment showed a 100% homology with the sequence of R. solani AG-4 AB000018. The nucleotide sequence has been assigned GenBank Accession No. FJ 534555. For pathogenicity tests, the inoculum of R. solani was prepared by growing the pathogen on PDA for 10 days. Five plants of 30-day-old A. flabellata were grown in 3-liter pots. Inoculum consisting of an aqueous suspension of PDA and mycelium disks (5 g of mycelium + agar per plant) was placed at the collar of plants. Five plants inoculated with water and PDA fragments alone served as control treatments. Plants were maintained in a greenhouse at temperatures between 20 and 24°C. The first symptoms, similar to those observed in the nursery, developed 7 days after the artificial inoculation. R. solani was consistently reisolated from infected leaves and stems. Control plants remained healthy. The pathogenicity test was carried out twice with similar results. The presence of R. solani AG1-IB on A. flabellata has been reported in Japan (4), while in the United States, Rhizoctonia sp. is described on Aquilegia sp. (3). This is, to our knowledge, the first report of leaf blight of A. flabellata caused by R. solani in Italy as well as in Europe. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. Carling. Grouping in Rhizoctonia solani by hyphal anastomosis reactions. In: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, The Netherlands, 1996. (3) D. F. Farr et al. Fungi on Plants and Products in the United States. The American Phytopathological Society, St Paul, MN, 1989. (4) E. Imaizumi et al. J. Gen. Plant Pathol. 66:210, 2000.

Lupinus polyphyllus (Leguminosae), Washington lupine, is a perennial herbaceous plant. In March 2008, in a campus greenhouse at the University of Torino, Grugliasco (northern Italy), a leaf blight was observed on 20% of potted 30-day-old plants. Semicircular, water-soaked lesions developed on leaves just above the soil line at the leaf-petiole junction and later along the leaf margins. Lesions expanded for several days along the midvein until the entire leaf was destroyed. Blighted leaves turned brown, withered, clung to the shoots, and matted on the surrounding foliage. Severely infected plants died. Plants were grown in a sphagnum peat/perlite/clay (70:20:10) substrate at temperatures between 18 and 25°C and relative humidity of 60 to 80%. Diseased tissue was disinfested for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 25 mg/liter of streptomycin sulfate. A fungus with the morphological characteristics of Rhizoctonia solani (4) was consistently and readily recovered, then transferred and maintained in pure culture. Ten-day-old mycelium grown on PDA at 20 ± 1°C appeared light brown, rather compact, and exhibited radial growth. The isolates of R. solani successfully anastomosed with tester isolate AG 4 (AG 4 RT 31, obtained from tobacco plants). The hyphal diameter at the point of anastomosis was reduced, the anastomosis point was obvious, and cell death of adjacent cells was observed. Results were consistent with other reports on anastomosis reactions (3). Pairings were also made with tester isolates AG 1, 2.1, 2.2, 3, 6, 7, 11, and BI with no anastomoses observed between the recovered and tester isolates. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 660-bp fragment showed 100% homology with the sequence of R. solani. The nucleotide sequence has been assigned GenBank Accession No. FJ486272. For pathogenicity tests, the inoculum of R. solani was prepared by growing the pathogen on PDA for 10 days. Plants of 30-day-old L. polyphyllus were grown in 10-liter containers (10 plants per container) on a steam disinfested sphagnum peat/perlite/clay (70:20:10) medium. Inoculum, consisting of an aqueous suspension of mycelium disks prepared from PDA cultures (5 g of mycelium per plant), was placed at the collar of plants. Plants inoculated with water and PDA fragments alone served as control treatments. Three replicates were used. Plants were maintained in a greenhouse at temperatures between 18 and 23°C. First symptoms, similar to those observed in the nursery, developed 10 days after the artificial inoculation. R. solani was consistently reisolated from infected leaves and stems. Control plants remained healthy. The pathogenicity test was repeated twice. The susceptibility of L. polyphyllus to R. solani was reported in Poland (2). This is, to our knowledge, the first report of leaf blight of L. polyphyllus caused by R. solani in Italy. The importance of the disease is at the moment limited. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) W. Blaszczak. Rocz. Nauk. Roln. Ser A 85:705, 1962. (3) D. E. Carling. Grouping in Rhizoctonia solani by hyphal anastomosis reactions. In: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, The Netherlands, 1996. (4) B. Sneh et al. Identification of Rhizoctonia species. The American Phytopathological Society, St Paul, MN, 1991.

Spider flower (Cleome hassleriana L. [synonym = C. spinosa]) is used as a tall border in parks and gardens worldwide. During July 2008, severe outbreaks of a powdery mildew were observed in a public park in Torino (northern Italy). Leaves were covered with dense, white hyphae and conidia, especially on the adaxial surface. Hyphae were also present on petioles and fruits, but not on petals and stems. As the disease progressed, infected leaves turned chlorotic, curled, and wilted. Conidia were hyaline, cylindrical, single, and measured 31.1 to 48.2 × 12.9 to 17.6 μm (average 37.1 × 15.6 μm). Germ tubes terminating in a moderately lobed appressorium were produced terminally. The cylindrical foot cells of the erect condiophores were 19.2 to 27.8 × 6.5 to 8.6 μm (average 23.3 × 7.7 μm). Fibrosin bodies were absent. Chasmothecia were observed mostly on the lower surfaces of leaves. At maturity, they were dark amber and spherical with a diameter of 92.9 to 151.0 μm (average 121.4 μm). Each chasmothecium contained six stalked asci (average size 63.7 × 35.9 μm). Each ascus contained four ellipsoid ascospores that measured 17.3 to 26.4 × 10.9 to 15.6 μm (average 23.3 × 12.8 μm). The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced (1). The 602-bp sequence was deposited in GenBank under the Accession No. GQ149478 and was 99% similar to that of Erysiphe cruciferarum (Accession No. EU140958). As proof of pathogenicity, diseased leaves of C. hassleriana were pressed against leaves of three healthy 4-month-old potted plants of the same species for 10 min. Three noninoculated plants served as controls. Inoculated and noninoculated plants were maintained in a greenhouse at 22 to 25°C in isolation. After 11 days, typical powdery mildew colonies developed on inoculated plants. Noninoculated plants did not develop symptoms. The pathogenicity test was repeated once. Powdery mildew on C. hassleriana caused by E. cruciferarum was reported in Italy (2) but the pathogen was not characterized. Herbarium specimens are deposited at AGROINNOVA Collection, University of Torino, Italy. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) U. Braun. The Powdery Mildews (Erysiphales) of Europe. Gustav Fischer Verlag, Jena, Germany, 1995.

In the summer of 2007, a wilt of endive (Cichorium endivia) cv. Myrna plants was observed on several commercial farms near Alessandria in northern Italy. Approximately 40% of the plants on each farm were symptomatic. Affected plants were stunted and yellow and their root systems were poorly developed. Basal leaves eventually wilted. Black streaks were observed in the proximal part of the leaf vascular system. Fusarium oxysporum was consistently isolated from symptomatic vascular tissue on a Fusarium-selective medium (1). To confirm identification of the pathogen, the translation elongation factor 1α and the ribosomal DNA intergenic spacer (IGS) region were partially sequenced (2). Genomic DNA was extracted from mycelia growing on potato dextrose agar. Amplification of the EF-1α region generated a sequence of 648 bp; the IGS amplicon was 2,500 bp. The EF-1α sequence (GenBank Accession No GQ398152) was 99% similar to the sequence of a F. oxysporum strain isolated from soil and a strain pathogenic on cotton plants (GenBank Accession No. EU246574). The IGS sequence (GenBank Accession No GQ398153) was 97% similar to the sequence of a F. oxysporum strain (GenBank Accession No. EF661647). Pathogenicity tests were conducted on 15-day-old endive plants (cv. Myrna). Ten plants were inoculated by dipping their roots in a 1 × 106 CFU/ml suspension of one of the isolates recovered from a wilted endive plant. Inoculated and noninoculated plants were transplanted into pots filled with steamed soil and maintained in a glasshouse at 23 to 28°C. Wilt symptoms and vascular discoloration of the roots, crown, and veins developed 60 days after inoculation. F. oxysporum was consistently reisolated from infected plants. Noninoculated plants remained healthy. The pathogenicity test was conducted twice. To our knowledge, this is the first report of wilt caused by F. oxysporum on endive in Italy. References: (1) H. Komada. Rev. Plant Prot. Res. 8:114, 1975. (2) G. Mbofung et al. Phytopathology 97:87, 2007.

In northern Italy, blue mold can occur generally on apples after 3 months of storage under controlled atmospheres. The mold can be caused by Penicillium griseofulvum Dierckx (synonym P. urticae Bainier). During 2008, several postharvest fruit rots were observed on apples (cv. Golden Delicious) after 180 to 240 days of storage at 1°C. Approximately 8% of the fruits showed blue mold. Apples had been cultivated in Aosta (Aosta Valley Region) and Lagnasco (Piedmont Region). Infected fruits showed soft, watery, brown spots enlarging rapidly at 20°C. There was a distinct margin between soft rotted flesh and firm healthy tissues. Under high humidity, masses of blue-green spores formed on the surface of the lesion. Apple fruit excisions from the margin between the healthy and diseased tissues were plated on potato dextrose agar (PDA), pH 5.6. The recovered fungus produced abundant mycelium and conidia, with the colonies attaining a diameter of 2.0 to 2.4 cm after 7 days at 20 ± 2°C on PDA. Colonies were mostly yellow-green, with a yellowish-to-orange brown underside. Conidiophores were mononematous or loosely synnematous, hyaline, with branches strongly divergent. Phialides were cylindrical with a very short neck. Conidia were ellipsoidal, sometimes subglobose, 2.5 to 3.5 × 2.2 to 2.5 μm, hyaline to greenish. Preliminary morphological identification of the fungus (2) was confirmed by PCR using genomic DNA extracted from mycelia of pure cultures. Two sequences, obtained through the amplification of ribosomal region ITS1-5.8S-ITS2 (1), were blast searched in GenBank and showed 99% sequence coverage and 99% similarity to ribosomal sequences of P. griseofulvum. Two sequences were deposited in GenBank with Accession Nos. HQ012498 (a strain from Aosta Valley) and HQ012499 (a strain from the Piedmont Region). Pathogenicity was tested on 20 ripe fruits each of four apple cultivars (Golden Delicious, Red Chief, Granny Smith, and Royal Gala). Fruits were surface sterilized with 1% sodium hypochlorite. Conidial suspensions (30 μl of 105 conidia/ml) of the fungus were placed on artificial wounds generated on the apple surface. Control fruits were treated with sterile water. Seven days after inoculation, the symptoms were reproduced on the four cultivars and P. griseofulvum was reisolated on PDA from the inoculated fruits of all four cultivars. Control fruits were symptomless. An analysis using high-performance liquid chromatography with diode array of the rotting tissues associated with inoculated fruits of all four cultivars (4) confirmed, as in the case of other strains of P. griseofulvum, the production of the mycotoxin patulin (12.1 to 44.4 mg kg–1). Previously, P. griseofulvum was reported on apple in other countries such as the United States (3), Japan, Egypt, and Brazil. To our knowledge, this is the first report of P. griseofulvum on apples during storage in Italy. References: (1) R. Nilsson et al. FEMS Microbiol. Lett. 296:97, 2009. (2) R. A. Samson and J. L. Pitt. Integration of Modern Taxonomic Methods for Penicillium and Aspergillus Classification. Harwood Academic Publishers, Singapore, 2001. (3) P. G. Sanderson and R. A. Spotts. Phytopathology 85:103, 1995. (4) D. Spadaro et al. Food Addit. Contam. B 1:134, 2008.

Spearmint (Mentha spicata) is grown for its aromatic and carminative oil and as an ornamental. During the fall of 2009, 4-month-old plants grown on a commercial farm located near Albenga (northern Italy) showed signs and symptoms of an unknown powdery mildew. The adaxial leaf surfaces were covered with white mycelia and conidia, while the abaxial surfaces were less infected. As the disease progressed, infected leaves turned yellow and wilted. Mycelia were also observed on stems. Conidia were hyaline, elliptical to doliform, borne in short chains (two to three conidia per chain), and measured 35 × 21 μm (30 to 43 × 18 to 26 μm). Conidiophores measured 86 × 11 μm (76 to 97 × 9 to 13 μm) followed by one to three shorter cells, measuring, respectively, 22 × 11 μm (13 to 28 × 9 to 15 μm). Fibrosin bodies were absent. Chasmothecia were not observed in the collected samples. The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS4/ITS6 and sequenced (1) (GenBank Accession No. HM053470). The 567-bp amplicon had 100% homology with the sequence of Golovinomyces biocellatus (GenBank Accession No. AB307675). Pathogenicity was confirmed through inoculation by gently pressing diseased leaves onto leaves of healthy M. spicata plants. Three plants were inoculated, while the same number of noninoculated plants served as a control. Plants were maintained at temperatures from 18 to 25°C. Twelve days after inoculation, typical symptoms of powdery mildew developed on inoculated plants. The fungus observed on inoculated plants was morphologically identical to that originally observed. Noninoculated plants did not show symptoms. The pathogenicity test was carried out twice. G. biocellatus has been reported on Mentha spp. in Australia (3) and the United States (4) and the pathogen is present on other plant genera in Italy. A similar powdery mildew of M. spicata was attributed to Erysiphe orontii in the United States (2). The economic importance of this disease is currently limited in Italy because of the limited planting of this host, but potted aromatic plants represent a steadily increasing crop in Italy. Voucher specimens are available at the Agroinnova Collection, University of Torino. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) S. T. Koike and G. S. Saenz. Plant Dis. 83:399, 1999. (3) J. R. Liberato and J. H. Cunnington. Australas. Plant Dis. Notes 2:83, 2007. (4) D. B. Marcum et al. Plant Dis. 94:276, 2010.

Euphorbia susannae (common name Suzane's spurge) and E. inermis (Euphorbiaceae family) are grown in pots and commercialized in northern Italy. In March 2012, plants of these species grown on the same commercial farm showed signs of powdery mildew. On E. susannae, apexes of stems were covered with white mycelia and conidia, with the ultimate development of necrosis on symptomatic tissues more interested by the disease. Of 5,000 plants, 5% were affected. Conidia were hyaline, elliptical, borne in short chains (two to three conidia per chain), and 27.7 (24.4 to 30.6) μm long and 16.1 (13.6 to 19.1) μm wide. Conidiophores were erect, with a foot cell straight or slightly flexuous, 82.8 (52.7 to 117.1) μm long and 10.0 (9.2 to 11.2) μm wide, followed by two to three shorter cells 19.8 (14.7 to 28.9) μm long and 10.7 (8.7 to 13.0) μm wide. On E. inermis, a white mycelium covered the stems starting from the apexes, causing yellowing and necrosis on leaves finally killing infected tissues. Of 500 plants, 80% were affected. Conidia were 33.2 (25.7 to 42.0) μm long and 17.3 (12.6 to 21.6) μm wide. Conidiophores were erect, with a foot cell straight or slightly flexuous, 96.7 (67.0 to 138.6) μm long and 9.5 (7.7 to 11.7) μm wide, followed by two to three shorter cells 26.3 (17.5 to 42.2) μm long and 11.8 (8.3 to 16.2) μm wide. Fibrosin bodies were present on both hosts, while chasmothecia were not observed in samples from either host. The internal transcribed spacer (ITS) region of rDNA of samples of mycelium and conidia collected from the two hosts was amplified using the primers ITS1-ITS4 (3) and directly sequenced (GenBank Accession Nos. JX179221 and JX179219 for E. susannae and E. inermis, respectively). By performing BLAST analysis, the 692-bp amplicon from E. susannae and the 541-bp amplicon from E. inermis showed 100% homology with several sequences of Podosphaera spp. On the basis of morphological characteristics of the imperfect state and the ITS analysis, the causal agent of powdery mildew on E. susannae and E. inermis was identified as Podosphaera sp. Pathogenicity was confirmed by gently brushing healthy 20-month-old potted plants of E. susannae and E. inermis with mycelia and conidia from diseased plants. Four plants/treatment/species were used. Non-inoculated plants belonging to the two species served as control. Plants were maintained in a glasshouse at temperatures ranging from 18 to 25°C and relative humidity from 65 to 80%. About 20 days after inoculation, typical symptoms of powdery mildew developed on inoculated plants. The fungus observed on inoculated plants was morphologically identical to the original isolate. Non-inoculated plants did not exhibit symptoms. The pathogenicity test was performed in duplicate. Several agents of powdery mildew have been reported on Euphorbia spp. Among others, Podosphaera euphorbiae was reported on numerous Euphorbiaceae (1), P. euphorbiae-hirtae was observed on E. hirta (1) and P. euphorbiae-helioscopiae on E. pekinensis (2). To our knowledge, this is the first report of Podosphaera sp. on E. susannae and E. inermis in Italy. This disease is not presently of economic importance. Specimens are available at the Agroinnova Collection. References: (1) U. Braun. A Monograph of the Erysiphales (Powdery Mildews). J. Cramer, Berlin-Stuttgard, German Democratic Republic, 1987. (2) S. Y. Liu. Plant Dis. 95:1314, 2011. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

During fall 2011, symptoms of a wilt disease were observed in a commercial nursery near Ventimiglia as well as in the Research Center of Floriculture of Sanremo (northern Italy) on plants of Papaver nudicaule (Iceland poppy) of a local unnamed cultivar. In the commercial nursery, 15 to 20% of plants were affected, while about 3% of plants were affected at the Research Center. Symptoms consisted of chlorosis, premature leaf drop, and foliar wilting, followed by the stem wilting, bending, and eventually rotting from the base. Brown discoloration was observed in the stem vascular tissue. Using Komada's Fusarium-selective agar medium (2), a fungus was consistently and readily isolated from symptomatic vascular tissue of plants collected from both sites. The isolates were purified and subcultured on potato dextrose agar (PDA), on which medium both isolates produced pale violet, abundant, aerial mycelium, felted in old cultures, with pale purple pigments in the agar medium. The isolate generated short monophialides with unicellular, ovoid-elliptical microconidia of 3.9 to 6.7 × 1.4 to 3.0 (average 5.4 × 2.3) μm. On carnation leaf agar (CLA) (1), isolates produced pale orange sporodochia with macroconidia that were 3-septate, slightly falcate with a foot-shaped basal cell and a short apical cell, and 26.0 to 43.5 × 3.1 to 4.4 (average 35.3 × 3.7) μm. Chlamydospores were abundant, terminal, and intercalary, rough walled, mostly singles but sometime in short chains or clusters, and 5.2 to 10.1 μm in diameter. Such characteristics are typical of Fusarium oxysporum (3). The internal transcribed spacer (ITS) region of rDNA was amplified from the isolates using the primers ITS1/ITS4 (4), and sequenced. BLASTn analysis of the 507-bp ITS sequence of one isolate from P. nudicaule collected from the commercial nursery (GenBank Accession No. JX103564) showed an E-value of 0.0 and 100% identity with the ITS sequence of F. oxysporum (HQ649820). To confirm pathogenicity of one of the Iceland poppy isolates, tests were conducted on 2-month-old plants of the same cultivar on which symptoms were first observed. Plants (n = 14) were inoculated by dipping roots in a 1 × 107 CFU/ml conidial suspension of the isolate of F. oxysporum prepared from 10-day-old cultures grown in potato dextrose broth (PDB) on a shaker (90 rpm) for 10 days at 22 ± 1°C (12-h fluorescent light, 12-h dark). Non-inoculated control plants (n = 14) were dipped in sterilized water. All the plants were transplanted into pots filled with steamed potting mix (sphagnum peat/perlite/pine bark/clay at 50:20:20:10), and maintained in a glasshouse at 24 to 28°C. Inoculated plants showed typical symptoms of Fusarium wilt after 10 days. The stems then wilted and plants died. Non-inoculated plants remained healthy. F. oxysporum was reisolated from inoculated plants but not from control plants. The pathogenicity test was conducted twice with the same results. Since Fusarium wilt has not previously been described on Iceland poppy at any location, this is first report of F. oxysporum on P. nudicaule in Italy and anywhere in the world. References: (1) N. L. Fisher et al. Phytopathology 72:151, 1982. (2) H. Komada. Rev. Plant Prot. Res. 8:114, 1975. (3) J. F. Leslie and B.A. Summerell. The Fusarium Laboratory Manual, Blackwell Professional, IA, 2006. (4) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990.

Satureja montana L. (winter savory “Repandens”) is an evergreen shrub. In late summer 2010, blight was observed on a farm near Albenga (northern Italy) on 3% of 500 potted 2-month-old plants. Semicircular, water-soaked lesions appeared first on stems then on leaves. As the disease progressed, blighted leaves turned brown, withered, clung to the shoots, and matted on the surrounding foliage within 5 to 6 days. Stem fragments taken from the margin of the diseased tissues of 10 plants were disinfected for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 100 μg/liter streptomycin sulfate. A fungus with morphological characters of Rhizoctonia solani was consistently isolated. Three isolates of R. solani obtained from affected plants were successfully anastomosed with R. solani isolate AG 1 (ATCC 58946). Three pairings were made for each tested strain. Hyphal diameter at the point of anastomosis was reduced, the anastomosis point was obvious, and death of adjacent cells was observed. Results were consistent with other reports on anastomosis reactions (2). Isolates from winter savory were paired with R. solani isolates AG 2, 3, 4, 6, 7, or 11 and examined microscopically. Anastomosis was not observed in any of the pairings. Tests were repeated once. Mycelium of 10-day-old isolates from winter savory appeared light brown, compact, and radiate. Numerous, dark brown sclerotia, 1 to 4 mm in diameter (average 1.7), developed within 20 days after transfer of mycelia to PDA in 90-mm-diameter petri dishes and incubated (11-h daylight, 13-h dark) at 21 to 24°C. Descriptions of mycelium and sclerotia were typical for subgroup IA Type 2 (3). The internal transcribed spacer (ITS) region of rDNA was amplified with primers ITS1/ITS4 and sequenced. BLASTn analysis (1) of the 696 bp showed a 99% homology with the sequence of R. solani. The nucleotide sequence has been assigned GenBank No. JQ313811. For pathogenicity tests, inoculum of R. solani was prepared by growing the pathogen on wheat kernels autoclaved in 1-liter glass flasks (30 min at 121°C and 1 atm) for 15 days. One of the isolates assigned to the anastomosis group AG 1 IA was tested. Five 90-day-old plants of S. montana were inoculated. Each plant grown in 2-liter pots in a steam disinfested peat/pumice/pine bark/clay mix (50:20:20:20:10) was inoculated with 10 g of infested wheat kernels placed at the base of the stem. Five plants inoculated with noninfested wheat kernels served as the control. Plants covered with plastic bags were arranged randomly in a growth chamber at 20 ± 1°C with 12-h light/dark for 5 days. Symptoms, similar to those observed in the farm, developed 4 days after inoculation. Ten colonies of R. solani were reisolated from infected leaves and stems of each inoculated plant. Control plants remained healthy. The pathogenicity test was carried out twice. Symptoms caused by R. solani have been recently observed on S. hortensis in Poland (4). This is, to our knowledge, the first report of blight of S. montana caused by R. solani in Italy. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. Carling. Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, The Netherlands, 1996. (3) R. T. Sherwood. Phytopathology 59:1924, 1969. (4) B. Zimowska. Herba Polonica 56:29, 2010.

During an extensive survey carried out in Piedmont (northern Italy) aimed at identifying the emerging soilborne diseases affecting tomato in commercial fields where alternatives to methyl bromide have been implemented in response to national and international regulations, sudden collapse of tomato plants, cv. Tomahawk, grafted on cv. Beaufort, were repeatedly observed in a commercial plastic tunnel operation. Affected plants suddenly collapsed 60 days after transplant during the month of May 2010. Symptoms included chlorosis, stunting, and severe root and crown rot, leading to sudden collapse of approximately 25% of the plants within 60 days of transplant. Symptomatic tissues from the root and collar of infected plants were surface disinfested for 1 min in a 1% NaOCl solution, rinsed for 5 min in water, and submerged in selective medium based on corn meal agar. A Phytophthora-like organism (2) with characteristic coenocytic hyphae was consistently isolated and transferred to V8 agar. The sporangia were spherical to ovoid, papillate, and 40 to 77 × 23 to 34 (average 55.1 × 30.3) μm. Oospores were globose and 22.2 to 30.8 μm. The internal transcribed spacer (ITS) region of rDNA of a single isolate was amplified using the primers ITS1/ITS4 and sequenced. BLAST analysis (1) of the 750-bp segment showed a 100% homology with the sequence of Phytophthora capsici JN382543.1. The nucleotide sequence has been assigned the GenBank Accession No. JX090306. Pathogenicity tests were performed on healthy 30-day-old tomato plants cv. Beaufort by using one strain of P. capsici grown for 15 days at 22 to 25°C on a mixture of 2:1 wheat/hemp kernels, and then 1 g per L of the inoculum was mixed into a substrate based on peat blonde/peat black (15:85 v/v). Two plants were transplanted into 3-L pots, with five replicates. Ten non-inoculated plants represented the control treatment; the trial was repeated once. All plants were kept in a greenhouse at temperatures ranging from 22 to 25°C. Inoculated plants became chlorotic 7 days after inoculation and root and crown rot developed 30 days after inoculation. Control plants remained symptomless. P. capsici consistently was reisolated from inoculated plants. In Italy, the presence of P. nicotianae on hybrids of Solanum lycopersicum × S. hirsutum is known (3), while, to the best of our knowledge, this is the first report of P. capsici on the hybrid S. lycopersicum × S. hirsutum in Italy. The economic importance of the disease can increase due to the expanding use of grafted tomato plants. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997 (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. APS Press, St Paul, MN, 1996. (3) A. Garibaldi and M. L. Gullino. Acta Hortic. 833:35, 2010. (4) H. M. Masago et al. Phytopathology 67:425, 1977.

During spring 2012, symptoms of an unusual leaf spot disease were observed in several commercial greenhouses near Salerno (southern Italy) on plants of Diplotaxis tenuifolia (cv Selvatica). The first symptoms on leaves of affected plants consisted of small (1 mm) black-brown spots of irregular shape, later coalescing into larger spots, 1 cm in diameter. Spots were surrounded by a yellow halo, and were mostly located on the foliar limb, rib, and petiole. Affected leaves were often distorted, appearing hook-like. The disease was severe under 75 to 90% RH, at air temperature of 20 to 26°C, and caused severe production losses on about 50 ha. Particularly, affected tissues rotted quickly after packaging and during transit and commercialization of processed rocket. Diseased tissue was excised, immersed in a solution containing 1% sodium hypochlorite for 60 s, rinsed in water, then placed on potato dextrose agar (PDA) medium, containing 25 mg/l of streptomycin sulphate. After 5 days, a fungus developed producing a whitish-orange mycelium when incubated under 12 h/day of fluorescent light at 22°C. The isolates obtained were purified on PDA. On this medium, they produced hyaline elliptical and ovoid conidia, sometimes one-septate, measuring 4.5 to 9.2 × 1.7 to 3.5 (average 6.8 × 2.6) μm. Conidia were born on phialides, measuring 6.8 to 20.2 × 1.3 to 3.1 (average 16.5 × 2.1) μm. Such characteristics are typical of Plectosphaerella sp. (2). The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 (3) and sequenced. BLAST analysis of the 519-bp segment showed a 98% similarity with the sequence of Plectosphaerella cucumerina (GenBank Accession No. AB469880). The nucleotide sequence has been assigned the GenBank Accession JX185769. To confirm pathogenicity, tests were conducted on 45-day-old D. tenuifolia plants. Plants (21/treatment), grown in 15 liter pots (7 plants/pot) were inoculated by spraying a 1 × 106 CFU/ml conidial suspension of one isolate of P. cucumerina, prepared from 10-day-old cultures, grown on PDA. Inoculated plants were maintained in a growth chamber at 23 ± 1°C, at 90% RH for 4 days. Non-inoculated plants served as control. Inoculated plants showed the typical first leaf spots 6 days after the artificial inoculation. Four days later, spots enlarged and leaves became distorted, showing chlorosis. Non-inoculated plants remained healthy. P. cucumerina was reisolated from inoculated plants. The pathogenicity test was conducted twice with identical results. This is, to our knowledge, the first report of P. cucumerina on D. tenuifolia in Italy as well as worldwide. P. cucumerina has been described as associated with root and collar rots of other horticultural crops in southern Italy (1). Due to the importance of the crop in Italy, this disease can cause serious economic losses. References: (1) A. Carlucci et al., Persoonia, 28:34, 2012. (2) M. E. Palm et al. Mycologia, 87:397, 1995. (3) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

Rebutia perplexa, Cactaceae family, is a clumping fine thorny cactus, producing several flushes of pink flowers. In the spring of 2013, a blight was observed in a farm located near Imperia (northern Italy) on 2% of 2,000 3-year-old plants, grown in plastic pots. Affected plants showed pale brown discoloration of stems, starting from the base, and eventually collapsed. Flowers also rotted and wilted. In the presence of high relative humidity, a rare, whitish mycelium developed on the surface of the substrate. Eventually, infected plants died. Symptomatic tissues of the stem were taken from 10 plants and plated on potato dextrose agar (PDA). A fungus with the morphological characters of Rhizoctonia solani (3) was consistently recovered. Three representative isolates obtained from affected plants were successfully paired with tester strains of R. solani (AG 1, AG 2-2-IIIB, AG 2-2-IV, AG 4, AG 7, AG 11) (2) and examined microscopically. Three replicated pairings were made for each tester strain. The Rebutia isolates anastomosed only with AG 2-2-IIIB tester strain with high hyphal fusion frequency. The hyphal diameter at the point of anastomosis was reduced, the anastomosis point was obvious, and death of adjacent cells was observed, indicating anastomosis reactions (1). Tests were performed twice. Mycelium of 15-day-old isolates maintained at 27 to 30°C, appeared whitish or pale buff in color, coarse, with a concentric zonation, scarce aerial mycelium, and without sclerotia. The optimum temperature for mycelium growth was 30°C (daily growth rate: 24.6 mm) and isolates grew also at 35°C. The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 and sequenced. BLASTn analysis of the 523-bp amplicon (GenBank Accession No. KF719318) showed a 99% homology with the sequence of the R. solani AG 2-2-IIIB isolate GU811672. The nucleotide sequence has been assigned the GenBank Accession No. KF719318. Therefore, on the basis of molecular characteristics, anastomosis tests, temperature growth, and cultural characteristics, the isolates from R. perplexa were identified as R. solani AG 2-2-IIIB. For pathogenicity tests, 3 g of colonized wheat kernel from 10-day-old cultures of a representative isolate of the fungus was added per 1 l of substrate in 12 potted healthy plants of R. perplexa. The inoculum was prepared by inoculating wheat kernels with the mycelium of 10-day-old cultures of the fungus and incubating at 25 ± 1°C (12 h fluorescent light, 12 h dark). Twelve plants inoculated with non-infested wheat kernels served as controls. Plants were covered with plastic bags and maintained in a growth chamber at 25 ± 1°C. The first symptoms, similar to those observed in the farm, developed 5 days after inoculation. Fifteen days after the artificial inoculation, all inoculated plants were dead. R. solani was re-isolated only from the stems of symptomatic plants. Control plants remained healthy. The pathogenicity test was carried out twice with similar results. This is, to our knowledge, the first report of blight of R. perplexa caused by R. solani in Italy as well as worldwide. References: (1) D. E. Carling. Grouping in Rhizoctonia solani by hyphal anastomosis reactions. In: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease control. Kluwer Academic Publishers, The Netherlands, pp. 37-47, 1996. (2) A. Ogoshi. Ann. Rev. Phytopathol. 25:125, 1987. (3) B. Sneh et al. Identification of Rhizoctonia species. APS Press, St Paul, MN, 1991.

Seed treatments with essential oils (from savory and thyme) and biocontrol agents (Pseudomonas spp. and Fusarium oxysporum) have been evaluated in vivo after dry hot air treatments against Fusarium oxysporum f. sp. basilici on basil seeds. The savory and thyme essential oils showed a significant pathogen control activity because of their innate antifungal activity and because of the seed application method, but the dry hot pre-treatment did not show any obvious effect on the performance of the essential oil treatments. The dry heat treatment improved the Pseudomonas seed dressing effect against F.oxysporum f. sp. basilici, and showed important reductions in plant infection and the disease index on the treated seed plants, without any negative effect on seed germination. However, the pathogen control provided by the heat treatments combined with the application of the biocontrol agents never reached the same performance as the chemical treatments considered as the reference. Thus, short dry heat treatments on basil seeds have been shown to be a valid but complementary seed disinfection method against Fusarium wilt.

Aims To identify cultivable filamentous fungi before ensiling, after silage conservation, in farm-silos covered with two different plastic films (polyethylene (PE) vs biodegradable (MB)), as well as after aerobic exposure of whole-crop corn silage. Methods and Results Molecular techniques coupled with traditional microbial counting were utilized to identify the predominant fungal species. The cultivable fungal population changed remarkably from harvesting to silo opening. Anaerobiosis and low pH reduced mould count and the presence of Fusarium species both under PE and MB film. However, in the peripheral areas of the silo, where air penetration could not be completely prevented, the fungal population did not decrease. The predominant fungal species after aerobic exposure of silage was Aspergillus fumigatus, without differences between the two plastic films. Conclusions Maintenance of anaerobiosis and a low pH also in the upper layer of the silo reduce the risk of mould growth during corn silage feed-out. Significance and Impact of the Study Even if the new MB plastic film did not completely maintain the anaerobiosis in the upper layer of silage, the overall silage quality was not compromised and was similar to that observed under PE, indicating that the development and use of MB film to cover silage is promising, but needs some improvement.

Symptoms of a vascular wilt were observed on many plants of Lavandula × allardii (hybrid of Lavandula dentata and L. latifolia) cultivated in a nursery near Albenga, Liguria region, Northern Italy. After identification based on morphological characteristic and ITS sequence analysis, the pathogen was identified as Fusarium oxysporum. Eight single-spore isolates obtained from infected tissues were used for a phylogenetic analysis in order to identify the forma specialis. Translation elongation factor 1-α (EF-1α), intergenic spacer (IGS) and three genes encoding for polygalacturonase genes (pg1, pg5 and pgx1) were amplified by PCR. Gene sequences were aligned with other formae speciales of Fusarium oxysporum obtained from GenBank databases in order to build phylogenetic trees. Results obtained for each genomic region showed a unique group with isolates derived from L. × allardii well separated from the other formae speciales. Results obtained, together with pathogenicity tests, allowed us to introduce a new forma specialis named F. oxysporum f. sp. lavandulae.

The susceptibility of nine Papaver species commonly grown for gardens, cut flowers and potted plants, to Fusarium wilt, caused by Fusarium oxysporum f. sp. papaveris, has been evaluated. The susceptibility of Chelidonium majus L. and Papaver rhoeas L., both belonging to Papaveraceae family and naturally present in Italian flora, was also tested. Plants were inoculated by dipping the roots into the conidial suspensions of each of five single-spore isolates of F. oxysporum f. sp. papaveris isolated from P. nudicaule grown in Italy. After appearance of the symptoms, the disease index (D.I.) was evaluated for each tested species that was successively assigned to one of the following susceptibility classes: R = resistant (D.I. 0–5); PR = partially resistant (D.I. 6–20); MS = moderately susceptible (D.I. 21–50); S = susceptible (D.I. 51–75); and HS = highly susceptible (D.I. 76–100). None of the tested species was found to be totally or partially resistant to F. oxysporum f. sp. papaveris. However, Papaver atlanticum (Ball) Cosson, P. dubium L., P. glaucum Boiss. and Hausskn., P. pseudocanescens Popov, P. nudicaule L., P. rupifragum Boiss. and Reuter and Papaver “Daneborg” were susceptible or highly susceptible to the pathogen, while P. trinifolium Boiss. and P. orientale L. showed an average susceptibility to the tested isolates. The susceptibility classes of Chelidonium majus L. and P. rhoeas L. ranged from moderately to highly susceptible. About the origin of F. oxysporum f. sp. papaveris, two hypotheses are discussed. The first hypothesis is related to the susceptibility of C. majus L. and P. rhoeas to F. oxysporum f. sp. papaveris. This fact indicates that this pathogen might have been present in the wild of Italy and that the wild species belonging to the Papaveraceae may be a potential sources of disease outbreaks. The second hypothesis is related to the climatic conditions of subpolar areas in which P. nudicaule is indigenous. Low temperatures might limit the appearance of plant symptoms caused by F. oxysporum, which is generally favored by elevated temperatures, such as those typical of glasshouse cultivation in Liguria region (north of Italy) where the pathogen was reported for the first time on P. nudicaule. The first hypothesis should be validated with further monitoring activities in order to isolate the pathogen on wild flora, whereas the second hypothesis should be confirmed with epidemiology tests.

Alternaria leaf-spot is a new disease recently reported on basil in Italy. The correct identification of Alternaria species has suffered from many reclassifications in function of morphological features and molecular data. In our study, we performed an overall approach to obtain a better characterization of basil Alternaria isolates. Morphological characteristics, seven-genome region phylogenic analysis, and secondary metabolite profile differentiated the majority of the isolates as A. alternata. OPA 1-3 and OPA 10-2 were the best molecular regions to discriminate among the isolates. Morphological characteristics and sporulation groups helped to discriminate A. tenuissima from A. alternata isolates. All isolates in the A. sect. Alternaria were mycotoxigenic and pathogenic on basil, the production of mycotoxins was enhanced on basil compared to in vitro conditions used in this work.