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1.
Phytopathology ; 114(1): 21-34, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37505093

RESUMEN

Species from the Botryosphaeriaceae family are the causal agents of Botryosphaeria dieback (BD), a worldwide grapevine trunk disease. Because of their lifestyle and their adaptation to a wide range of temperatures, these fungi constitute a serious threat to vineyards and viticulture, especially in the actual context of climate change. Grapevine plants from both nurseries and vineyards are very susceptible to infections by botryosphaeriaceous fungi due to several cuts and wounds made during their propagation process and their entire life cycle, respectively. When decline becomes chronic or apoplectic, it reduces the longevity of the vineyard and affects the quality of the wine, leading to huge economic losses. Given the environmental impact of fungicides, and their short period of effectiveness in protecting pruning wounds, alternative strategies are being developed to fight BD fungal pathogens and limit their propagation. Among them, biological control has been recognized as a promising and sustainable alternative. However, there is still no effective strategy for combating this complex disease, conditioned by both fungal life traits and host tolerance traits, in relationships with the whole microbiome/microbiota. To provide sound guidance for an effective and sustainable integrated management of BD, by combining the limitation of infection risk, tolerant grapevine cultivars, and biological control, this review explores some of the factors conditioning the expression of BD in grapevine. Among them, the lifestyle of BD-associated pathogens, their pathogenicity factors, the cultivar traits of tolerance or susceptibility, and the biocontrol potential of Bacillus spp. and Trichoderma spp. are discussed.


Asunto(s)
Ascomicetos , Fungicidas Industriales , Trichoderma , Vitis , Vitis/microbiología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología
2.
Plant Dis ; 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38537147

RESUMEN

Carob tree (Ceratonia siliqua L.) is a crop native to the Mediterranean Basin mainly being used as livestock feed, in pharmaceutical industry, and also a valuable source of human food due to the high dietary fibre and sugar contents. In January 2023, one-year-old 'Duraio' carob trees grafted on 'Rojal' rootstock on pots showing dark brown to necrotic lesions on the secondary roots, decline symptoms and leading to the death of some plants, were detected in a nursery located at the Valencian Community region in Spain. Disease severity was 40 to 50% of root area and disease incidence was approximately 50% on approximately 1000 plants. Six representative plants were randomly collected. Roots were washed under running tap water to rinse the soil away, and small symptomatic pieces were cut, disinfected with 70% ethanol, and then dried on absorbent paper. Two-mm-long segments were plated on CMA-PARBPH, a Phytophthora-selective medium, and incubated at 25ºC. After 2-3 days, growing colonies were transferred to potato dextrose agar (PDA) medium. A Phytophthora-like organism was consistently isolated (50% of root segments, n= 120). Colonies were whitish with irregular margins, had coenocityc mycelium, irregularly branched hyphal swellings, and chlamydospores were absent. Sporangia were non-papillate, persistent, ellipsoid and measuring 25 to 40 × 50 to 90 µm (average: 35.5 × 74.7 µm, n = 50). They proliferated internally with both nested and extended proliferation. These morphological features were similar to those of Phytophthora niederhauserii (Abad et al., 2014). Internal transcribed spacer (ITS) and cytochrome c oxidase I (COX1) regions of a representative isolate CF3 were sequenced to confirm the identity. Both sequences were deposited in GenBank under accession numbers OR763816 for ITS and OR783697 for COX1. OR763816 showed 99.87% sequence identity to P. niederhauserii strain Ex-type MG865552 and OR783697 showed 99.85% sequence identity to P. niederhauserii strain Ex-type MH136944 (Abad et al., 2023). Pathogenicity test was performed on one-year-old carob tree seedlings (Duraio/Rojal) grown in 13 cm-diameter pots to fulfill Koch's postulates. The inoculum was prepared in 1 L glass flasks with a mixture of 200 ml vermiculite, 20 ml oat grains, and 175 ml of V8 broth (20% V8 juice and 0.2% of CaCO3 in demineralized water) (Jung et al., 1996). Glass flasks with vermiculite/oat/V8 mixture were autoclaved three times for 20 min at 120 ºC. These mixtures were inoculated with the isolate CF3 which was previously grown on V8 agar medium and incubated for six weeks in the dark at room temperature (Pérez-Sierra et al., 2013). For inoculation, twenty-gram inoculum were mixed with 200 g autoclaved potting mix (peat, vermiculite and sand; 1:1:1, v/v/v), and added to the pots to plant the seedlings. Seven plants were inoculated and non-infested vermiculite/oat/V8 mixture was used to prepare seven control plants. Two months after inoculation one of the inoculated plants died. Six months after inoculation, only the inoculated plants showed decline symptoms with dry leaves and root necrosis. Isolates resembling P. niederhauserii were recovered by plating the roots from all inoculated plants on CMA-PARBPH, and the identity of the isolates was confirmed as P. niederhauserii based on ITS and COX1 sequencing. To our knowledge, this is the first report of P. niederhauserii causing root rot on carob tree. The detection of this pathogen in nurseries is relevant because its dissemination to orchards could have a negative impact in carob crop production.

3.
Plant Dis ; 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38301223

RESUMEN

In 2021, grapevines (Vitis vinifera L.) cv. Callet growing in a commercial vineyard located at Pollença (northeast of the island of Majorca, Spain) showed severe symptoms of shoot blight during spring and early summer, with an incidence of 70%. Symptoms consisted of elongated cankered-like lesions, surrounded by water-soaked darker tissues, that developed at the base or around the middle nodes of the shoot. For fungal isolation, shoot samples with lesions were collected, surface disinfected with 2% NaCl for 90s, rinsed twice with deionized water and placed in Petri plates containing potato dextrose agar (PDA). The plates were incubated at 25°C under 12 h light-darkness for 6 days. Isolations consistently yielded on kind of fungal colonies that produced white mycelium and black spherical to elongated sclerotia (2 to 10 mm in diameter). Morphological characterization was consistent with the description of Sclerotinia sclerotiorum (Lib.) de Bary (Bolton et al. 2006). Three isolates (UIB 118-1, UIB 118-26, and UIB 129-41) were preserved and deposited in the Culture Collection of Microbiology-Faculty of Sciences, University of Balearic Islands, Spain. Genomic DNA was extracted from isolates UIB 118-26 and UIB 129-41 using the EZNA Miniprep Kit (Omega Bio-Tek, Norcross, GA). The internal transcribed spacer (ITS) region of ribosomal DNA, ß-tubulin (BTUB) and calmodulin (CAL) gene regions were amplified using ITS1F-ITS4 (Gardes and Bruns, 1996; White et al. 1990), Bt-2a/Bt-2b (Glass and Donaldson 1995) and CAL228F/CAL737R (Carbone and Kohn 1999) primer sets, respectively. Amplicons were sequenced and deposited in GenBank with accession numbers MZ604647 and MZ604648 for ITS, OK634402 and OK634403 for BTUB and OK634404 and OK634405 for CAL. BLASTn search showed that isolates were >99 % (ITS, BTUB and CAL) identical to S. sclerotiorum GenBank accession no. KF859933, CP017815 and KF871381, respectively. Pathogenicity tests were conducted using eight one-year old grapevines cv. Cabernet Sauvignon. Old and new green shoots were inoculated by inserting a 6-mm plug of mycelium taken from actively growing cultures on PDA into cuts made at the base and at the distal part of each shoot with a sterile scalpel with a total of eight inoculation points per plant. Inoculated wounds were sealed with Parafilm tape to avoid rapid dehydration. Inoculated plants and an equal number of wounded but non-inoculated plants (negative controls) were maintained at 25 ± 1°C for 48 h in plastic containers to ensure a high relative humidity (>90%). After 5 days, the infection girdled and rotted the green new shoots, whereas the older partially lignified shoots developed a localized long brown lesion that reached 16 cm in length. Due to the rotting of the basal part of the petiole, leaves turned gray, wilted, and died, easily detaching from the stem. In advanced stages of the disease, 7 days after infection, branches died and fell with the leaves remained attached (Fig 1 A, B). Reisolations from diseased shoots were successfully performed on PDA to fulfill Koch's postulates. S. slerotiorum was previously reported on grapevine causing shoot blight in Chile (Latorre and Guerrero, 2001), Korea (Jong-Han et al. 2009), California-USA (Boland and Hall, 1994) and Australia (Hall et al. 2002). AlsoS. sclerotiorum was reported among the endophytic mycobiota associated with Vitis vinifera in the Iberian Peninsula (Gonzalez and Tello, 2011) but not as a pathogen causing visible symptoms on that crop. So, this is the first report of the occurrence of S. slerotiorum as a pathogen of grapevines in Spain causing symptoms of canker and shoot blight. This finding highlights a potential risk of this fungal disease for the wine industry in the Mediterranean region and specially for Spain, the country with the largest acreage devoted to grapevines. Although chemical and biological are suitable control strategies, disease management is difficult as sclerotia of Sclerotinia can remain in the soil for up to eight years (Adams and Ayears, 1979), and preventive surveys are greatly recommended as an important epidemiological tool to monitor the epidemiology of disease and identify potential outbreaks of this new pathogen on grapevine in Spain.

4.
Plant Dis ; 107(5): 1499-1509, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36320134

RESUMEN

Diseases caused by soilborne oomycetes are a limiting factor for the cultivation of Prunus spp., which makes the choice of a suitable rootstock a key factor. The objective of this study was to evaluate the pathogenicity of 12 oomycete species belonging to the genera Globisporangium, Phytophthora (Ph.), and Phytopythium (Pp.) to three Prunus hybrid rootstocks: 'Garnem', 'GF-677', and 'Rootpac-40'. These three rootstocks are widely used to grow stone fruit and almond in the Mediterranean Basin. Pathogenicity tests were conducted using 15 oomycete isolates and 1-year-old rootstock seedlings. Ninety days after inoculation, disease symptoms were evaluated on a severity scale, and the area under the disease progression curve and the survival probability of the inoculated seedlings were calculated. Moreover, root dry weight was recorded. All the isolates included in the pathogenicity tests were pathogenic on the rootstock seedlings and were reisolated from root lesions. Large differences in virulence were detected among the different oomycete species and isolates of Ph. niederhauserii for each rootstock. Phytophthora multivora and Pp. helicoides were generally the most virulent species. The results of the present research offer substantial contribution to increase our knowledge about the pathogenicity of several oomycete species that are frequently isolated in Prunus orchards and the potential risks that they pose for Prunus spp. crops.


Asunto(s)
Phytophthora , Prunus , Virulencia , Enfermedades de las Plantas , Frutas , Plantones
5.
Plant Dis ; 106(7): 1890-1897, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35021872

RESUMEN

Twenty-five almond cultivars were assessed for susceptibility to Diaporthe amygdali, causal agent of twig canker and shoot blight disease. In laboratory experiments, growing twigs were inoculated with four D. amygdali isolates. Moreover, growing shoots of almond cultivars grafted onto INRA 'GF-677' rootstock were used in 4-year field inoculations with one D. amygdali isolate. In both types of experiments, inoculum consisted of agar plugs with mycelium, which were inserted underneath the bark, and the lesion lengths caused by the fungus were measured. Necrotic lesions were observed in the inoculated almond cultivars in both laboratory and field tests, confirming the susceptibility of all evaluated cultivars to all inoculated isolates of D. amygdali. Cultivars were grouped as susceptible or very susceptible according to a cluster analysis. The relationship between some agronomic traits and cultivar susceptibility was also investigated. Blooming and ripening times were found to be relevant variables explaining cultivar performance related to D. amygdali susceptibility. Late and very late blooming and early and medium ripening cultivars were highly susceptible to D. amygdali. Our results may provide valuable information that could assist in ongoing breeding programs of this crop and in the selection of cultivars for new almond plantations.


Asunto(s)
Ascomicetos , Prunus dulcis , Fitomejoramiento , Enfermedades de las Plantas/microbiología , Prunus dulcis/genética , Prunus dulcis/microbiología
6.
Plant Dis ; 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33779259

RESUMEN

Nectarine (Prunus persica (L.) Batsch var. nucipersica (Suckow) C. K. Schneid.) is a fruit crop widely cultivated throughout the Mediterranean basin. In Spain, it is mainly grown in eastern regions of the country. In March 2018, 5-year-old nectarine trees showing twig canker symptoms were observed after a rainy spring period in a 0.5 ha orchard located at Alaior, Menorca island (Spain). Cankers were frequent on affected trees (approximately, 80% of the total trees), thus leading to shoot blight. Ten twig segments of one-year old wood with cankers were cut, washed under running tap water, surface disinfected for 1 min in a 1.5% sodium hypochlorite solution and rinsed twice in sterile distilled water. Small pieces (2 mm) of affected tissues were taken from the margin of the cankers and plated on potato dextrose agar (PDA) supplemented with 0.5 g/L of streptomycin sulphate (PDAS). The plates were then incubated at 25 ºC in the dark for 7 to 10 d. Actively growing colonies were first hyphal-tipped and then transferred to PDA and 2% water agar supplemented with sterile pine needles and incubated at 21-22ºC under a 12h/12h near UV / darkness cycle during 21 d (León et al. 2020). Colonies were white at first, becoming light cream, with visible solitary and aggregate pycnidia at maturity. Alpha conidia were aseptate, fusiform, hyaline, multi-guttulated (mean ± SD = 7.4 ± 0.7 × 2.8 ± 0.4 µm, n = 100). Beta and gamma conidia were not observed. The morphological and cultural characteristics of the isolates were congruent with those of Diaporthe spp. (Gomes et al. 2013). The ITS1-5.8S-ITS2 (ITS) region and fragments of ß-tubulin (tub2), the translation elongation factor 1-alpha (tef1-α) gene regions, histone H3 (his3) and calmodulin (cal) genes of representative isolate DAL-59 were amplified and sequenced (Santos et al. 2017). The BLASTn analysis revealed 100% similarity with sequences of D. mediterranea (Synonym D. amygdali) (Hilário et al. 2021) isolate DAL-34 from almond (ITS: MT007489, tub2: MT006686, tef1-α: MT006989, his3: MT007095 and cal: MT006761). Sequences of isolate DAL-59 were deposited in GenBank Database (ITS: MT007491, tub2: MT006688, tef1-α: MT006991, his3: MT007097 and cal: MT006763). Pathogenicity tests were conducted using one-year-old potted plants of nectarine cv. Boreal, which were inoculated with isolate DAL-59. In each plant, a 3 mm wound was made in the center of the main branch (about 30 cm length) with a scalpel. Colonized agar plugs with 3 mm diameter, which were obtained from active 10-day-old colonies growing on PDA, were inserted underneath the epidermis and the wounds sealed with Parafilm. Inoculated plants were incubated in a growth chamber at 23 ºC with 12 h of light per day. Controls were inoculated with uncolonized PDA plugs. There were twelve plants per treatment, which were arranged in a completely randomized design. Five days after inoculation necrosis development was observed in the area of inoculation. Wilting and twig blight symptoms over the lesion occurred 3-wk after inoculation and pycnidia were detected, while the controls remained asymptomatic. Diaporthe amygdali was re-isolated from symptomatic tissues and identified as described above to satisfy Koch's postulates. To our knowledge, this is the first report of D. amygdali causing twig canker and shoot blight disease on nectarine in Spain.

7.
Plant Dis ; 105(11): 3657-3668, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34096766

RESUMEN

A field survey conducted on asymptomatic grapevine propagation material from nurseries and symptomatic young grapevines throughout different regions of Algeria yielded a collection of 70 Phaeoacremonium-like isolates and three Cadophora-like isolates. Based on morphology and DNA sequence data of ß-tubulin (tub2) and actin, five Phaeoacremonium species were identified including Phaeoacremonium minimum (22 isolates), Phaeoacremonium venezuelense (19 isolates), Phaeoacremonium parasiticum (17 isolates), Phaeoacremonium australiense (8 isolates), and Phaeoacremonium iranianum (4 isolates). The latter two species (P. australiense and P. iranianum) were reported for the first time in Algeria. Multilocus phylogenetic analyses (internal transcribed spacer, tub2, and translation elongation factor 1-α) and morphological features, allowed the description of the three isolates belonging to the genus Cadophora (WAMC34, WAMC117, and WAMC118) as a novel species, named Cadophora sabaouae sp. nov. Pathogenicity tests were conducted on grapevine cuttings cultivar Cardinal. All the identified species were pathogenic on grapevine cuttings.


Asunto(s)
Vitis , Argelia , Secuencia de Bases , Filogenia , Enfermedades de las Plantas
8.
Gastrointest Endosc ; 92(2): 269-275, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32119939

RESUMEN

BACKGROUND AND AIMS: Variceal hemorrhage can be a life-threatening adverse event of chronic liver disease. In contrast to the well-described guidelines for the management of portal hypertension (PH) in adults, there is limited evidence about the optimal prophylactic management of variceal bleeding in children. This study was carried out to assess the efficacy of endoscopic variceal ligation (EVL) as primary prophylaxis to prevent upper GI bleeding in children with PH. METHODS: From January 2014 to April 2018, all pediatric patients with PH disease and medium to large esophageal varices or reddish spots, regardless of the grade of the varix, were prospectively included in the protocol of primary prophylaxis with EVL. A second retrospective group of patients was made after reviewing medical records of 32 pediatric patients with PH that presented esophageal varices in the upper endoscopy and had received propranolol as primary prophylaxis. RESULTS: Twenty-four patients (75%) reached varices eradication in the EVL group, with a median of 2 procedures (range, 1-4) before eradication and a median time to eradication of 3.40 months (range, 1.10-13.33). No EVL-related adverse events were observed. Statistically significant differences were observed in the bleeding rate at 3 years between propranolol and EVL groups (6/32 [21.9%] vs 1/32 [3.2%], P < .02). The hazard ratio for bleeding for patients treated with propranolol compared with those treated with EVL was 2.6 (95% confidence interval, 1.53-3.67). CONCLUSIONS: EVL is a safe and effective treatment to prevent upper GI bleeding in pediatric patients with PH. (Clinical trial registration number: NCT03943784.).


Asunto(s)
Várices Esofágicas y Gástricas , Hipertensión Portal , Adulto , Niño , Várices Esofágicas y Gástricas/complicaciones , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/prevención & control , Humanos , Hipertensión Portal/complicaciones , Ligadura , Estudios Retrospectivos
9.
Phytopathology ; 110(6): 1216-1225, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32129711

RESUMEN

Although the fungus Phaeomoniella chlamydospora is the most commonly detected causal agent of Petri disease and esca, two important fungal grapevine trunk diseases, little is known about the dispersal patterns of P. chlamydospora inoculum. In this work, we studied the dispersal of P. chlamydospora airborne inoculum from 2016 to 2018 in two viticultural areas of eastern (Ontinyent) and northern (Logroño) Spain. The vineyards were monitored weekly from November to April using microscope slide traps, and P. chlamydospora was detected and quantified by a specific real-time quantitative (qPCR) method set up in this work. The method was found to be sensitive, and a good correlation was observed between numbers of P. chlamydospora conidia (counted by microscope) and DNA copy numbers (quantified by qPCR). We consistently detected DNA of P. chlamydospora at both locations and in all seasons but in different quantities. In most cases, DNA was first detected in the last half of November, and most of the DNA was detected from December to early April. When rain was used as a predictor of P. chlamydospora DNA detection in traps, false-negative detections were observed, but these involved only 4% of the total. The dispersal pattern of P. chlamydospora DNA over time was best described (R2 = 0.765 and concordance correlation coefficient = 0.870) by a Gompertz equation, with time expressed as hydrothermal time (a physiological time accounting for the effects of temperature and rain). This equation could be used to predict periods with a high risk of dispersal of P. chlamydospora.


Asunto(s)
Ascomicetos , Vitis , Granjas , Enfermedades de las Plantas , España
10.
Plant Dis ; 102(11): 2083-2100, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30189159

RESUMEN

Cylindrocarpon-like asexual morphs infect herbaceous and woody plants, mainly in agricultural scenarios, but also in forestry systems. The aim of the present study was to characterize a collection of Cylindrocarpon-like isolates recovered from the roots of a broad range of forest hosts from nurseries showing decline by morphological and molecular studies. Between 2009 and 2012, 17 forest nurseries in Spain were surveyed and a total of 103 Cylindrocarpon-like isolates were obtained. Isolates were identified based on DNA sequences of the partial gene regions histone H3 (his3). For the new species, the internal transcribed spacer and intervening 5.8S nrRNA gene (ITS) region, ß-tubulin (tub2), and translation elongation factor 1-α (tef1) were also used to determine their phylogenetic position. Twelve species belonging to the genera Cylindrodendrum, Dactylonectria, and Ilyonectria were identified from damaged roots of 15 different host genera. The species C. alicantinum, D. macrodidyma, D. novozelandica, D. pauciseptata, D. pinicola, D. torresensis, I. capensis, I. cyclaminicola, I. liriodendri, I. pseudodestructans, I. robusta, and I. rufa were identified. In addition, two Dactylonectria species (D. hispanica sp. nov. and D. valentina sp. nov.), one Ilyonectria species (I. ilicicola sp. nov.), and one Neonectria species (N. quercicola sp. nov.) are newly described. The present study demonstrates the prevalence of this fungal group associated with seedlings of diverse hosts showing decline symptoms in forest nurseries in Spain.


Asunto(s)
Hypocreales/aislamiento & purificación , Enfermedades de las Plantas/microbiología , Árboles/microbiología , Agricultura Forestal , Bosques , Hypocreales/citología , Hypocreales/genética , Micelio , Filogenia , Plantones/microbiología , España , Esporas Fúngicas , Encuestas y Cuestionarios , Madera/microbiología
11.
J Clin Microbiol ; 55(5): 1396-1407, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28202792

RESUMEN

The immigration of Latin American women of childbearing age has spread the congenital transmission of Chagas disease to areas of nonendemicity, and the disease is now a worldwide problem. Some European health authorities have implemented screening programs to prevent vertical transmission, but the lack of a uniform protocol calls for the urgent establishment of a new strategy common to all laboratories. Our aims were to (i) analyze the trend of passive IgG antibodies in the newborn by means of five serological tests for the diagnosis and follow-up of congenital Trypanosoma cruzi infection, (ii) assess the utility of these techniques for diagnosing a congenital transmission, and (iii) propose a strategy for a prompt, efficient, and cost-effective diagnosis of T. cruzi infection. In noninfected newborns, a continuous decreasing trend of passive IgG antibodies was observed, but none of the serological assays seroreverted in any the infants before 12 months. From 12 months onwards, serological tests achieved negative results in all the samples analyzed, with the exception of the highly sensitive chemiluminescent microparticle immunoassay (CMIA). In contrast, in congenitally infected infants, the antibody decline was detected only after treatment initiation. In order to improve the diagnosis of congenital T. cruzi infection, we propose a new strategy involving fewer tests that allows significant cost savings. The protocol could start 1 month after birth with a parasitological test and/or a PCR. If negative, a serological test would be carried out at 9 months, which if positive, would be followed by another at around 12 months for confirmation.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedad de Chagas/diagnóstico , Inmunidad Materno-Adquirida/inmunología , Inmunoglobulina G/sangre , Transmisión Vertical de Enfermedad Infecciosa , Trypanosoma cruzi/inmunología , Anticuerpos Antiprotozoarios/inmunología , Enfermedad de Chagas/parasitología , Preescolar , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Inmunoglobulina G/inmunología , Lactante , Recién Nacido , Tamizaje Masivo/métodos , Reacción en Cadena de la Polimerasa/métodos , Pruebas Serológicas , España
12.
Plant Dis ; 100(12): 2483-2491, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30686161

RESUMEN

In this study, 31 almond orchards with trees showing severe decline symptoms were surveyed from 2009 to 2014 on the island of Mallorca (Spain). In all, 45 Botryosphaeriaceae isolates were collected and characterized based on phenotypical features and comparisons of DNA sequence data of the nuclear ribosomal DNA-internal transcribed spacer region and elongation factor 1-α gene. Five species were identified as Diplodia olivarum, D. seriata, Neofusicoccum luteum, N. mediterraneum, and N. parvum. Pathogenicity tests were performed on four cultivars ('Pons', 'Vivot', 'Jordi', and 'Ferragnes') under field conditions for two consecutive years (2013 to 2014), and confirmed that all five species cause canker and dieback of almond, with Neofusicoccum spp. more virulent than Diplodia spp. in both years. Jordi was less sensitive to fungal infection in 2013. First reports from almond in Spain include N. mediterraneum and N. luteum.

13.
Phytopathology ; 104(6): 650-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24328492

RESUMEN

Verticillium wilts caused by the soilborne fungus Verticillium dahliae are among the most challenging diseases to control. Populations of this pathogen have been traditionally studied by means of vegetative compatibility groups (VCGs) under the assumption that VCGs comprise genetically related isolates that correlate with clonal lineages. We aimed to resolve the phylogenetic relationships among VCGs and their subgroups based on sequences of the intergenic spacer region (IGS) of the ribosomal DNA and six anonymous polymorphic sequences containing single-nucleotide polymorphisms (VdSNPs). A collection of 68 V. dahliae isolates representing the main VCGs and subgroups (VCGs 1A, 1B, 2A, 2B, 3, 4A, 4B, and 6) from different geographic origins and hosts was analyzed using the seven DNA regions. Maximum parsimony (MP) phylogenies inferred from IGS and VdSNP sequences showed five and six distinct clades, respectively. Phylogenetic analyses of individual and combined data sets indicated that certain VCG subgroups (e.g., VCGs 1A and 1B) are closely related and share a common ancestor; however, other subgroups (e.g., VCG 4B) are more closely related to members of a different VCG (e.g., VCG 2A) than to subgroups of the same VCG (VCG 4B). Furthermore, MP analyses indicated that VCG 2B is polyphyletic, with isolates placed in at least three distinct phylogenetic lineages based on IGS sequences and two lineages based on VdSNP sequences. Results from our study suggest the existence of main VCG lineages that contain VCGs 1A and 1B; VCGs 2A and 4B; and VCG 4A, for which both phylogenies agree; and the existence of other VCGs or VCG subgroups that seem to be genetically heterogeneous or show discrepancies in their phylogenetic placement: VCG 2B, VCG 3, and VCG 6. These results raise important caveats regarding the interpretation of VCG analyses: genetic homogeneity and close evolutionary relationship between members of a VCG should not be assumed.


Asunto(s)
Productos Agrícolas/microbiología , Variación Genética , Enfermedades de las Plantas/microbiología , Verticillium/genética , ADN de Hongos/química , ADN de Hongos/genética , ADN Intergénico/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Genética de Población , Datos de Secuencia Molecular , Filogenia , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
14.
Pest Manag Sci ; 79(5): 1674-1683, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36573682

RESUMEN

BACKGROUND: Grapevine trunk diseases (GTDs) are a complex group of diseases that lead to major economic losses in all wine-producing countries. The investigation of biocontrol agents (BCAs) capable of forestalling or at least minimizing the development of GTDs has, recently, become a priority. Nursery experiments were set up to (i) assess the biocontrol effect of Trichoderma atroviride (Ta) SC1 and Bacillus subtilis (Bs) PTA-271, alone and in simultaneous application, against Botryosphaeria dieback (BOT)- and black-foot (BF)- associated pathogens during the grapevine propagation process and (ii) evaluate the success of the BCA inoculation during the grapevine propagation process, using quantitative reverse-transcription polymerase chain reaction techniques. RESULTS: The results demonstrated a significant reduction in the percentage of potentially infected plants and the percentage of fungal isolation from wood fragments of BOT and BF pathogens in nursery material treated with Ta SC1 and Bs PTA-271, respectively. In one of the experiments, simultaneous treatments with Bs PTA-271 and Ta SC1 caused a reduction in percentages of potentially infected plants and fungal isolation, from wood fragments containing BOT and BF pathogens. CONCLUSION: These biological treatments may be relevant components of an integrated approach, using complementary management strategies to limit infection by GTD pathogens, but further research is still needed to elucidate the effectiveness of Bs PTA-271 and the benefits of simultaneous application with Ta SC1 for the control of GTD pathogens in nurseries. © 2022 Society of Chemical Industry.


Asunto(s)
Ascomicetos , Vitis , Bacillus subtilis , Vitis/microbiología , Enfermedades de las Plantas/prevención & control , Enfermedades de las Plantas/microbiología
15.
Span J Psychiatry Ment Health ; 16(3): 169-174, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-32499122

RESUMEN

INTRODUCTION: People with schizophrenia have neurocognitive as well as social cognition deficits. Numerous studies have shown impairment in these domains in patients with chronic schizophrenia. However, these disturbances during the early phase of the disease have been less studied. OBJECTIVE: The aim of the study is to explore the theory of mind (ToM) and emotional processing in first-episode patients, compared to healthy subjects. METHOD: Forty patients with a first psychotic episode of less than 5 years' duration, and 40 healthy control subjects matched by age and years of schooling were assessed. The measures of social cognition included four stories of false belief, the Reading the Mind in the Eyes Test (RMET) and the Pictures Of Facial Affect (POFA) series. RESULTS: The patients with a first psychotic episode performed significantly worse in all tasks of social cognition, compared to the healthy controls. The second-order ToM was impaired whereas the first-order ToM was preserved in the patients. Happiness was the emotion most easily identified by both patients and controls. Fear was most difficult for the patients, while for the controls it was disgust. CONCLUSIONS: Deficits in ToM and emotional processing are present in patients with a first psychotic episode.


Asunto(s)
Trastornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/complicaciones , Cognición Social , Pruebas Neuropsicológicas , Trastornos Psicóticos/psicología , Emociones
16.
PeerJ ; 11: e16354, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37901471

RESUMEN

Citrus crops are affected by many fungal diseases. Among them, Citrus Black Spot caused by the ascomycete Phyllosticta citricarpa is particularly economically damaging wherever it occurs. Many other species of Phyllosticta are described on Citrus, but only P. citricarpa is considered a quarantine pest on the European continent. In order to prevent the introduction of this species into Europe, it is essential to have a detection test which can reliably identify it, and not confuse it with other species present on citrus, notably P. paracitricarpa. The latter taxon has recently been described as very close to P. citricarpa, and most detection tests do not allow to distinguish the two species. In this work, we exploited the genomic data of 37 isolates of Phyllosticta spp. from citrus, firstly to assess their phylogenetic relationships, and secondly to search for genomic regions that allowed the definition of species-specific markers of P. citricarpa. Analysis of 51 concatenated genes separated P. citricarpa and P. paracitricarpa in two phylogenetic clades. A locus was selected to define a hydrolysis probe and primers combination that could be used in real-time PCR for the specific detection of the quarantine species, to the exclusion of all others present on Citrus. This test was then thoroughly validated on a set of strains covering a wide geographical diversity, and on numerous biological samples to demonstrate its reliability for regulatory control. The validation data highlighted the need to check the reliability of the test in advance, when a change of reagents was being considered.


Asunto(s)
Ascomicetos , Citrus , Filogenia , Citrus/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Genómica , Ascomicetos/genética
17.
J Aging Stud ; 63: 101030, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36462913

RESUMEN

If (older) gay men have recurrently been stereotyped as hypersexual and as sexually voracious, they have also been represented as weak and effeminate, miserable and lonely, and as less manly than their heterosexual counterparts (Goltz, 2014; Freeman, 2010). Quite often, as Goltz reminds us, the two stereotypes intersect, as in classic films such as Death in Venice, Gods and Monsters, or Love and Death on Long Island, to name but a few, where ageism and homophobia combine to judge intergenerational relations as inappropriate and gay characters as "dirty old men" eager to recover their lost youth. Given these negative images, it is no wonder, then, that both youthism and ableism have become part and parcel of contemporary gay culture, which may also be linked to the few positive cultural images available of aging or disabled gay male bodies (Goltz, 2014). Starting off from the assumption that bodies are shaped and reshaped in complex interactions between physical and symbolic dimensions, the paper will demonstrate, however, how (auto)biographical narratives of older gay men, what we call "egodocuments," may be useful to rethink such traditional (mis)conceptions. Crossing the traditional divide between the Social Sciences and the Humanities, the study will draw on both life stories and film representations of older gay men in Spain, focusing on Spanish director Pedro Almodóvar's (2019) latest film, Pain and Glory, as a (semi-)autobiographical re-vision of traditional representations of gay men's aging. While Almodovar's protagonist and alter-ego, Salvador Mallo, appears as "prematurely aged" (Curtis and Thompson, 2015) due to bodily pain and disability, the film also travels back and forth from Mallos's childhood and youth to his maturity. This shows aging not only as a life-course experience, but also helps redefine it as a "queer" rather than linear or "straight" experience (Halberstam), allowing for both "pain and glory" to coexist in old age. Almodóvar's portraiture of gay aging will be compared to the life stories collected in a number of focus groups with Spanish older gay men, which will provide equally complex, varied, and often contradictory narratives.


Asunto(s)
Películas Cinematográficas , Minorías Sexuales y de Género , Humanos , Masculino , Niño , Adolescente , Anciano , Hombres , Narración , Dolor
18.
Am J Gastroenterol ; 106(10): 1787-95, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21625271

RESUMEN

OBJECTIVES: After an acute variceal bleeding, early decision for aggressive management of patients with worse prognosis may improve outcomes. The effectiveness of currently recommended standard therapy (drugs plus endoscopic ligation) for different risk subgroups and the validity of available risk criteria in clinical practice are unknown. METHODS: We analyzed data of 301 consecutive cirrhotic patients admitted with esophageal variceal bleeding. All patients received antibiotics, somatostatin, and in 263 early endoscopic therapy. A stratified 6-week mortality assessment according to risk (low-risk: Child-Pugh B without active bleeding or Child-Pugh A; high-risk: Child-Pugh B with active bleeding or Child-Pugh C) was performed. A multivariate analysis was conducted to elaborate a new risk classification rule. RESULTS: Among the 162 patients receiving emergency ligation, 14% rebled and 16% died. Standard therapy was very effective in all risk strata, even in high-risk patients, specially if eligible for therapeutic trials (child <14, age ≤75 years, creatinine ≤3.0 mg/dl, no hepatocellular carcinoma, or portal thrombosis), showing this stratum a 10% mortality. In patients receiving ligation, Child-Pugh C patients with baseline creatinine <1.0 mg/dl showed similar mortality to Child-Pugh A or B patients (8% vs. 7%, respectively). Only Child-Pugh C patients with creatinine ≥1.0 were at a significant higher risk (Child-Pugh C: 46% mortality if creatinine ≥1.0 vs. 8% if creatinine <1.0, P=0.006). CONCLUSIONS: The combination of somatostatin, antibiotics, and endoscopic ligation after an acute variceal bleeding in a real-life situation is associated with very low mortality. Child-Pugh C patients with baseline creatinine ≥1.0 mg/dl should be considered high-risk patients in this setting.


Asunto(s)
Antibacterianos/uso terapéutico , Várices Esofágicas y Gástricas/complicaciones , Hemorragia Gastrointestinal/tratamiento farmacológico , Hemorragia Gastrointestinal/cirugía , Somatostatina/uso terapéutico , Enfermedad Aguda , Adulto , Anciano , Terapia Combinada/métodos , Quimioterapia Combinada , Esofagoscopía , Femenino , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/mortalidad , Humanos , Ligadura , Modelos Logísticos , Masculino , Registros Médicos , Persona de Mediana Edad , Análisis Multivariante , Reproducibilidad de los Resultados , Proyectos de Investigación , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad
19.
Front Microbiol ; 12: 726132, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721323

RESUMEN

Grapevine trunk diseases (GTDs) are a big threat for global viticulture. Without effective chemicals, biocontrol strategies are developed as alternatives to better cope with environmental concerns. A combination of biological control agents (BCAs) could even improve sustainable disease management through complementary ways of protection. In this study, we evaluated the combination of Bacillus subtilis (Bs) PTA-271 and Trichoderma atroviride (Ta) SC1 for the protection of Chardonnay and Tempranillo rootlings against Neofusicoccum parvum Bt67, an aggressive pathogen associated to Botryosphaeria dieback (BD). Indirect benefits offered by each BCA and their combination were then characterized in planta, as well as their direct benefits in vitro. Results provide evidence that (1) the cultivar contributes to the beneficial effects of Bs PTA-271 and Ta SC1 against N. parvum, and that (2) the in vitro BCA mutual antagonism switches to the strongest fungistatic effect toward Np-Bt67 in a three-way confrontation test. We also report for the first time the beneficial potential of a combination of BCA against Np-Bt67 especially in Tempranillo. Our findings highlight a common feature for both cultivars: salicylic acid (SA)-dependent defenses were strongly decreased in plants protected by the BCA, in contrast with symptomatic ones. We thus suggest that (1) the high basal expression of SA-dependent defenses in Tempranillo explains its highest susceptibility to N. parvum, and that (2) the cultivar-specific responses to the beneficial Bs PTA-271 and Ta SC1 remain to be further investigated.

20.
Front Plant Sci ; 12: 726461, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34712253

RESUMEN

Fungal grapevine trunk diseases (GTDs) are some of the most pressing threats to grape production worldwide. While these diseases are associated with several fungal pathogens, Phaeomoniella chlamydospora and Phaeoacremonium minimum are important contributors to esca and Petri diseases. Recent research has linked grapevine xylem diameter with tolerance to Pa. chlamydospora in commercial rootstocks. In this study, we screen over 25 rootstocks for xylem characteristics and tolerance to both Pa. chlamydospora and Pm. minimum. Tolerance was measured by fungal incidence and DNA concentration (quantified via qPCR), while histological analyses were used to measure xylem characteristics, including xylem vessels diameter, density, and the proportion of the stem surface area covered by xylem vessels. Rootstocks were grouped into different classes based on xylem characteristics to assess the potential association between vasculature traits and pathogen tolerance. Our results revealed significant differences in all the analyzed xylem traits, and also in DNA concentration for both pathogens among the tested rootstocks. They corroborate the link between xylem vessels diameter and tolerance to Pa. chlamydospora. In Pm. minimum, the rootstocks with the widest xylem diameter proved the most susceptible. This relationship between vasculature development and pathogen tolerance has the potential to inform both cultivar choice and future rootstock breeding to reduce the detrimental impact of GTDs worldwide.

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