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Cross infection of multiple hosts by fungal trunk pathogens has been reported to occur worldwide. It supports the hypothesis that infected hosts adjacent to vineyards may serve as sources of inoculum for these pathogens. Among the alternative hosts, different studies have shown that almond represents a rich catch-crop for many fungal trunk pathogens. The hyphomycetes Collophora hispanica, Phaeoacremonium (Pm.) amygdalinum, Pm. iranianum and Pleurostomophora richardsiae have recently been isolated from wood samples with internal necroses and brown to black vascular streaking of almond trees showing symptoms of decline in Spain, although their status as pathogens was so far unknown. We inoculated almond trees cv. Ferragnes with these fungal species in greenhouse experiments to determine their pathogenic potential. All of them infected, colonised and produced lesions statistically different from the control, Pl. richardsiae being the most aggressive. Therefore, Co. hispanica, Pm. amygdalinum, Pm. iranianum and Pl. richardsiae should be considered as trunk pathogens of almond trees.

Cross infection of multiple hosts by fungal trunk pathogens has been reported to occur worldwide. It supports the hypothesis that infected hosts adjacent to vineyards may serve as sources of inoculum for these pathogens. Among the alternative hosts, different studies have shown that almond represents a rich catch-crop for many fungal trunk pathogens. The hyphomycetes Collophora hispanica, Phaeoacremonium (Pm.) amygdalinum, Pm. iranianum and Pleurostomophora richardsiae have recently been isolated from wood samples with internal necroses and brown to black vascular streaking of almond trees showing symptoms of decline in Spain, although their status as pathogens was so far unknown. We inoculated almond trees cv. Ferragnes with these fungal species in greenhouse experiments to determine their pathogenic potential. All of them infected, colonised and produced lesions statistically different from the control, Pl. richardsiae being the most aggressive. Therefore, Co. hispanica, Pm. amygdalinum, Pm. iranianum and Pl. richardsiae should be considered as trunk pathogens of almond trees.

[EN] A standard area diagram set (SAD) to aid visual assessment of loquat scab (caused by Fusicladium eriobotryae) severity on fruit was developed and evaluated for improving accuracy, precision and reliability of visual estimates. The SAD set contains eight black and white diagrams of diseased fruit with severity values from 2 % to 98 %. To evaluate the SADs, a group of 20 raters (comprising 10 'experienced' and 10 'inexperienced' raters) assessed the same set of 50 images three times, the first without SADs and the second and third using the SADs as an aid. Only for the group of inexperienced raters did SADs significantly improve accuracy (bias correction factor, C (b) = 0.93 without SADs and 0.98 with SADs), precision (correlation coefficient, r = 0.88 without SADs and r = 0.96 with SADs) and overall agreement (Lin's concordance correlation coefficient, rho (c) = 0.82 without SADs and rho c with SADs = 0.95) of the estimates. Accuracy and precision of the estimates by inexperienced raters were significantly higher than those obtained by the experienced raters, especially for the second assessment with SADs. Inter-rater reliability was improved when SADs were used by inexperienced raters, whereas a high degree of intra-rater reliability was obtained by both experienced and inexperienced raters when using SADs. The SADs developed in this study were useful for obtaining more accurate, precise and reliable assessments of loquat scab for inexperienced raters, and should be used as an aid for assessing scab in epidemiological studies or monitoring for decision-making purposes.

[EN] A standard area diagram set (SAD) to aid visual assessment of loquat scab (caused by Fusicladium eriobotryae) severity on fruit was developed and evaluated for improving accuracy, precision and reliability of visual estimates. The SAD set contains eight black and white diagrams of diseased fruit with severity values from 2 % to 98 %. To evaluate the SADs, a group of 20 raters (comprising 10 'experienced' and 10 'inexperienced' raters) assessed the same set of 50 images three times, the first without SADs and the second and third using the SADs as an aid. Only for the group of inexperienced raters did SADs significantly improve accuracy (bias correction factor, C (b) = 0.93 without SADs and 0.98 with SADs), precision (correlation coefficient, r = 0.88 without SADs and r = 0.96 with SADs) and overall agreement (Lin's concordance correlation coefficient, rho (c) = 0.82 without SADs and rho c with SADs = 0.95) of the estimates. Accuracy and precision of the estimates by inexperienced raters were significantly higher than those obtained by the experienced raters, especially for the second assessment with SADs. Inter-rater reliability was improved when SADs were used by inexperienced raters, whereas a high degree of intra-rater reliability was obtained by both experienced and inexperienced raters when using SADs. The SADs developed in this study were useful for obtaining more accurate, precise and reliable assessments of loquat scab for inexperienced raters, and should be used as an aid for assessing scab in epidemiological studies or monitoring for decision-making purposes.

[EN] Dispersal of conidia of Fusicladium eriobotryae, the causal agent of loquat scab, was investigated in two loquat orchards in Spain from 2010 to 2012. A volumetric spore sampler, horizontally and vertically orientated microscope slides, and rain collectors were placed in loquat fields to trap conidia of F. eriobotryae. No conidia were collected in the volumetric sampler, and highly variable numbers of conidia were collected in the rain gatherers. Large numbers of conidia were collected by microscope slides, particularly by those held in a horizontal orientation compared with those held in a vertical orientation. Approximately 90 % of the F. eriobotryae conidia were collected during rainy periods. Based on ROC and Bayesian analysis, using a parts per thousand yen 0.2 mm rainfall as a cut-off value resulted in a high probability of correctly predicting actual conidial dispersal, and had a low probability of failing to predict actual conidial dispersal. Based on the index of dispersion and the binary power law, the incidence of loquat scab on fruit was highly aggregated in space between and within trees, and aggregation was influenced by disease incidence. Our results demonstrate, for the first time, that F. eriobotryae is dispersed mainly in rain splash. The results will be integrated into a mechanistic, weather-driven, disease prediction model that should help growers to minimize fungicide application for the management of loquat scab.

[EN] Two commercial nurseries located in Comunidad Valenciana region (central-eastern Spain) were sampled in 2010 to evaluate whether the grapevine nursery propagation process could be a source of black-foot disease pathogens. Samples were taken from four sources of the propagation process: pre-grafting hydration tanks, scissors used for cutting buds, omega-cut grafting machines, and peat used for callusing. DNA from these samples was extracted and multiplex nested-PCR using primers specific for "Cylindrocarpon" pauciseptatum, Ilyonectria liriodendri and I. macrodidyma-complex (composed of I. alcacerensis, I. estremocensis, I. macrodidyma, I. novozelandica, I. torresensis, and two undescribed species) was used to identify the species present. Ilyonectria liriodendri and I. macrodidyma-complex were detected in hydration tanks, scissors, grafting machines and peat, I. macrodidyma-complex being the most frequent. Additionally, ten grafted cuttings each from five grapevine scion/rootstock combinations were collected from each nursery immediately after callusing, and again after one growing season in a nursery field. Roots of these grafted cuttings and plants were sampled to isolate the fungal pathogens. Only I. torresensis was isolated after callusing, while I. liriodendri, I. novozelandica and I. torresensis were isolated after one growing season, showing the highest incidence at this latter sampling time. Moreover, DNA was extracted from roots and analyzed as described before. Ilyonectria liriodendri and I. macrodidyma-complex were also detected at both sampling times. The use of the multiplex nested-PCR technique improved the detection of I. liriodendri and I. macrodidyma-complex from grafted cuttings and plants in both nurseries. This work shows that the grapevine nursery propagation process should be considered as a potential infection source for black-foot disease pathogens, and confirms that infections caused by Ilyonectria spp. in grapevine planting material inc

[EN] Little information is currently available regarding the number of species of black-foot and Petri disease pathogens present in soil and their capacity to infect grapevine roots and reach the xylem vessels. Seedlings of grapevine rootstock 41-B, and cvs. Bobal and Palomino were planted both in pots containing soil samples collected from commercial vineyards and in nursery fields. Roots and xylem vessels were later analyzed for fungal isolation. Black-foot pathogens: Ilyonectria alcacerensis, I. macrodidyma, I. novozelandica and I. torresensis were frequently isolated from roots of seedlings grown in all soils evaluated, whereas Petri disease pathogens: Cadophora luteo-olivacea, Phaeoacremonium aleophilum, Pm. parasiticum and Phaeomoniella chlamydospora were only isolated from xylem vessels of seedlings grown in nursery soils, with a low incidence. Ilyonectria alcacerensis, I. novozelandica and I. torresensis were isolated for the first time from grapevines in Spain, and Pm. parasiticum and Ca. luteo-olivacea were detected for the first time in nursery soils. Our results confirm nursery and vineyard soils as an important inoculum source for black-foot pathogens and demonstrate the presence of several Petri disease pathogens in nursery soils.

[EN] Forty-two kiwifruit orchards from Rize and Samsun provinces (Black Sea region, Turkey) exhibiting symptoms of root rot disease were examined between 2009 and 2010. Twenty-four fungal isolates recovered from affected roots were included in this study. Morphological characteristics of all isolates were recorded on potato dextrose agar, malt extract agar and Spezieller Nahrstoffarmer agar. The effect of temperature on radial colony growth was also evaluated at 5, 10, 15, 20, 25, 30, and 35 A degrees C. Histone H3 gene (HIS) was amplified with primers CYLH3F and CYLH3R and the amplified fragments were sequenced. The HIS phylogeny grouped all the isolates into six well-supported clades which were in agreement with phenotypical characteristics. Isolates were identified as "Cylindrocarpon" pauciseptatum, Cylindrocladiella parva, Ilyonectria liriodendri, I. torresensis, I. robusta and I. europaea, I. liriodendri being the most frequent species. All of them are reported for the first time on kiwifruit in Turkey, with the exception of I. liriodendri. Pathogenicity tests with selected isolates showed that 10 out of 11 isolates tested were able to induce typical root rot disease symptoms, affecting plant development and leading to the death of some plants. This study shows the high diversity of root rot pathogens found in kiwifruit trees in the Black Sea region of Turkey, being the first step towards a better understanding and management of the disease in local conditions.

[EN] Fifty eight single-spore Togninia minima (anamorph Phaeoacremonium aleophilum) isolates were recovered from grape rootstock wood of plants that showed symptoms of Petri disease and esca from 2001 to 2008 in Spain. These isolates were studied by means of mating type distribution, UP-PCR analysis, and virulence assays. Analysis of clone-corrected data sets showed equal frequencies of both mating types in the entire Spanish population, in the Ciudad Real region, at inter-vineyard and intra-vine spatial scales; while unequal mating type distribution was detected in Valencia and Zaragoza regions, at intra-vineyard and intra-vine spatial scales. This is the first study on distribution of T. minima mating types on spatial scales varying from vineyards to regions. A total of 49 polymorphic UP-PCR markers were obtained using seven UP-PCR primers. Four optimal clusters were inferred with Bayesian structure and multivariate analyses from the UP-PCR data. The high number of unique genotypes observed within the Spanish population, combined with a near-equal distribution of mating types, suggested that sexual reproduction probably does occur. However, based on allele distribution and frequency, each of the three subpopulations appeared to be evolving independently. Gene and genotype diversities across the subpopulations were similar and ranged from 0.24 to 0.27 and from 0.27 to 0.37, respectively. The detection of genetically identical isolates within and among subpopulations indicates that an asexual reproductive component should not be excluded. Contrast analysis among groups defined by UP-PCR analyses showed no significant differences in the virulence of T. minima isolates.

[EN] Forty-two kiwifruit orchards from Rize and Samsun provinces (Black Sea region, Turkey) exhibiting symptoms of root rot disease were examined between 2009 and 2010. Twenty-four fungal isolates recovered from affected roots were included in this study. Morphological characteristics of all isolates were recorded on potato dextrose agar, malt extract agar and Spezieller Nahrstoffarmer agar. The effect of temperature on radial colony growth was also evaluated at 5, 10, 15, 20, 25, 30, and 35 A degrees C. Histone H3 gene (HIS) was amplified with primers CYLH3F and CYLH3R and the amplified fragments were sequenced. The HIS phylogeny grouped all the isolates into six well-supported clades which were in agreement with phenotypical characteristics. Isolates were identified as "Cylindrocarpon" pauciseptatum, Cylindrocladiella parva, Ilyonectria liriodendri, I. torresensis, I. robusta and I. europaea, I. liriodendri being the most frequent species. All of them are reported for the first time on kiwifruit in Turkey, with the exception of I. liriodendri. Pathogenicity tests with selected isolates showed that 10 out of 11 isolates tested were able to induce typical root rot disease symptoms, affecting plant development and leading to the death of some plants. This study shows the high diversity of root rot pathogens found in kiwifruit trees in the Black Sea region of Turkey, being the first step towards a better understanding and management of the disease in local conditions.

[EN] Fifty eight single-spore Togninia minima (anamorph Phaeoacremonium aleophilum) isolates were recovered from grape rootstock wood of plants that showed symptoms of Petri disease and esca from 2001 to 2008 in Spain. These isolates were studied by means of mating type distribution, UP-PCR analysis, and virulence assays. Analysis of clone-corrected data sets showed equal frequencies of both mating types in the entire Spanish population, in the Ciudad Real region, at inter-vineyard and intra-vine spatial scales; while unequal mating type distribution was detected in Valencia and Zaragoza regions, at intra-vineyard and intra-vine spatial scales. This is the first study on distribution of T. minima mating types on spatial scales varying from vineyards to regions. A total of 49 polymorphic UP-PCR markers were obtained using seven UP-PCR primers. Four optimal clusters were inferred with Bayesian structure and multivariate analyses from the UP-PCR data. The high number of unique genotypes observed within the Spanish population, combined with a near-equal distribution of mating types, suggested that sexual reproduction probably does occur. However, based on allele distribution and frequency, each of the three subpopulations appeared to be evolving independently. Gene and genotype diversities across the subpopulations were similar and ranged from 0.24 to 0.27 and from 0.27 to 0.37, respectively. The detection of genetically identical isolates within and among subpopulations indicates that an asexual reproductive component should not be excluded. Contrast analysis among groups defined by UP-PCR analyses showed no significant differences in the virulence of T. minima isolates.

[EN] Little information is currently available regarding the number of species of black-foot and Petri disease pathogens present in soil and their capacity to infect grapevine roots and reach the xylem vessels. Seedlings of grapevine rootstock 41-B, and cvs. Bobal and Palomino were planted both in pots containing soil samples collected from commercial vineyards and in nursery fields. Roots and xylem vessels were later analyzed for fungal isolation. Black-foot pathogens: Ilyonectria alcacerensis, I. macrodidyma, I. novozelandica and I. torresensis were frequently isolated from roots of seedlings grown in all soils evaluated, whereas Petri disease pathogens: Cadophora luteo-olivacea, Phaeoacremonium aleophilum, Pm. parasiticum and Phaeomoniella chlamydospora were only isolated from xylem vessels of seedlings grown in nursery soils, with a low incidence. Ilyonectria alcacerensis, I. novozelandica and I. torresensis were isolated for the first time from grapevines in Spain, and Pm. parasiticum and Ca. luteo-olivacea were detected for the first time in nursery soils. Our results confirm nursery and vineyard soils as an important inoculum source for black-foot pathogens and demonstrate the presence of several Petri disease pathogens in nursery soils.

Pythium isolates were recovered from endive plants (Cichorium endivia) showing vascular necrosis collected from commercial fields located in Castellón province (eastern Spain). They were identified as Pythium tracheiphilum on the basis of their phenotypical and molecular profile. Pathogenicity tests conducted with two P. tracheiphilum isolates, obtained from endive and lettuce (Lactuca sativa), respectively, in this region, confirmed that both isolates were pathogenic to endive, with no significant differences in virulence between them. This is the first report of vascular necrosis caused by P. tracheiphilum on endive in Spain.

Pythium isolates were recovered from endive plants (Cichorium endivia) showing vascular necrosis collected from commercial fields located in Castellón province (eastern Spain). They were identified as Pythium tracheiphilum on the basis of their phenotypical and molecular profile. Pathogenicity tests conducted with two P. tracheiphilum isolates, obtained from endive and lettuce (Lactuca sativa), respectively, in this region, confirmed that both isolates were pathogenic to endive, with no significant differences in virulence between them. This is the first report of vascular necrosis caused by P. tracheiphilum on endive in Spain.