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Vine shoots were successfully used to produce butanol by ABE fermentation. Biomass pretreatment and enzymatic hydrolysis were optimised to obtain high sugar concentrations while reducing inhibitor generation. Thirty-one Clostridium strains were compared in order to select the most adequate one for the fermentation of vine shoot hydrolysates. Clostridium beijerinckii CECT 508 produced 7-8 g/L butanol with the only addition of CaCO3, FeSO4·7H2O and NH4Cl to the hydrolysates. In addition, CaCO3 could be replaced by eggshell to further reduce reagent costs., This study was funded by the European Regional Development Fund (ERDF) within the programme Interreg V-A España-Portugal (POCTEP) 2014-2020 through the project BIOVINO (0688_BIOVINO_6_E).

Background: Xanthomonas arboricola pv. pruni (Xap) causes bacterial spot of stone fruits and almond, an important disease that may reduce the yield and vigour of the trees, as well as the marketability of affected fruits. Xap lies within the Xanthomonas genus, which has been intensively studied because of its strain specialization and host range complexity. Here, we summarize the recent advances in our understanding of the complexities of Xap, including studies of the molecular features that result after comparative phenotypic and genomic analyses, in order to obtain a clearer overview of the bacterial behaviour and infection mechanism in the context of the X. arboricola species. Taxonomic status: Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Xanthomonadales; Family Xanthomonadaceae; Genus Xanthomonas; Species X. arboricola; Pathovar pruni. Host range and symptoms: Xap infects most Prunus species, including apricot, peach, nectarine, plum and almond, and occasionally cherry. Symptoms are found on leaves, fruits, twigs and branches or trunks. In severe infections, defoliation and fruit dropping may occur. Distribution: Bacterial spot of stone fruits and almond is worldwide in distribution, with Xap being isolated in Africa, North and South America, Asia, Europe and Oceania. It is a common disease in geographical areas in which stone fruits and almonds are grown. Xap is listed as a quarantine organism in several areas of the world. Genome: The genomes of six isolates from Xap have been publicly released. The genome consists of a single chromosome of around 5 000 000 bp with 65 mol% GC content and an extrachromosomal plasmid element of around 41 000 bp with 62 mol% GC content. Genomic comparative studies in X. arboricola have allowed the identification of putative virulence components associated with the infection process of bacterial spot of stone fruits and almond. Disease control: Management of bacterial spot of stone fruits and almond is based on an integrated approach that comprises essential measures to avoid Xap introduction in a production zone, as well as the use of tolerant or resistant plant material and chemical treatments, mainly based on copper compounds. Management programmes also include the use of appropriate cultivation practices when the disease is already established. Finally, for the effective control of the disease, appropriate detection and characterization methods are needed for use in symptomatic or asymptomatic samples as a first approach for pathogen exclusion. USEFUL WEBSITES: https://gd.eppo.int/taxon/XANTPR; http://www.cost.eu/COST_Actions/ca/CA16107; http://www.xanthomonas.org.

Xanthomonas arboricola is a species in genus Xanthomonas which is mainly comprised of plant pathogens. Among the members of this taxon, X. arboricola pv. pruni, the causal agent of bacterial spot disease of stone fruits and almond, is distributed worldwide although it is considered a quarantine pathogen in the European Union. Herein, we report the draft genome sequence, the classification, the annotation and the sequence analyses of a virulent strain, IVIA 2626.1, and an avirulent strain, CITA 44, of X. arboricola associated with Prunus spp. The draft genome sequence of IVIA 2626.1 consists of 5,027,671Â bp, 4,720 protein coding genes and 50 RNA encoding genes. The draft genome sequence of strain CITA 44 consists of 4,760,482Â bp, 4,250 protein coding genes and 56 RNA coding genes. Initial comparative analyses reveals differences in the presence of structural and regulatory components of the type IV pilus, the type III secretion system, the type III effectors as well as variations in the number of the type IV secretion systems. The genome sequence data for these strains will facilitate the development of molecular diagnostics protocols that differentiate virulent and avirulent strains. In addition, comparative genome analysis will provide insights into the plant-pathogen interaction during the bacterial spot disease process.

La Red FRUTSAN 112RT0441, perteneciente al Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED), se inició en 2011 y en él participan investigadores de España, Argentina, Bolivia, Brasil, Chile y Uruguay. El objetivo de FRUT-SAN es profundizar en el conocimiento científico-tecnológico de las principales enfermedades y plagas que afectan el cultivo de los frutales de hueso para optimizar conjuntamente las estrategias de control integrado. En este trabajo se revisan comparativamente la situación y conocimientos sobre la mancha bacteriana de los frutales de hueso y del almendro (Xanthomonas arboricola pv. pruni) en España y Sudamérica.

La mancha bacteriana de los frutales de hueso y del almendro es una enfermedad emergente en España. Está causada por Xanthomonas arboricola pv. pruni, patógeno considerado de cuarentena en la Unión Europea y por la European and Mediterranean Plant Protection Organization. La bacteria se identificó en nuestro país en el año 2002 y, desde entonces, se han detectado nuevos brotes en distintas Comunidades Autónomas. En este trabajo se describen aspectos sobre la sintomatología, epidemiología y medidas de control de esta bacteriosis

Se realizó un estudio durante los años 2002, 2003 y 2004, con el fin de determinar la composición, la abundancia, riqueza, diversidad, equidad, ocurrencia y fluctuación temporal de las especies de saltahojas en tres zonas productoras de café de Costa Rica. Se utilizaron trampas amarillas pegajosas para clasificar y cuantificar el número de saltahojas adultos durante el período de muestreo. Se encontró un total de 82.500 individuos, pertenecientes a 139 especies ubicadas dentro de nueve subfamilias. San Isidro de León Cortés presentó la mayor diversidad entre los sitios estudiados. Veinticinco especies se encontraron frecuentemente en al menos uno de los sitios muestreados, y solamente Coelidiana sp.1, Osbornellus sp.1, Scaphytopius sp.1 y Empoasca sp. se capturaron a lo largo de todo el período de estudio. La fluctuación temporal de los taxa que comprenden los principales vectores de X. fastidiosa Wells et al. mostró diferencias entre las zonas estudiadas. A survey was conducted during 2002, 2003 and 2004 to determine the leafhopper species composition, abundance, richness, diversity, evenness, occurrence and flight activity among three coffee production zones of Costa Rica. Yellow sticky traps were used to qualify and quantify the number of aerial leafhoppers during the sampling period. A total of 82,500 individuals, belonging to 139 species within nine leafhopper subfamilies, were trapped. San Isidro de León Cortés site presented the highest diversity from the three surveyed sites. Twenty five species were frequently trapped at least in one of the studied zones, and only Coelidiana sp.1, Osbornellus sp.1, Scaphytopius sp.1 and Empoasca sp. were trapped throughout the sampling period. The flight activity of the taxa that contain the main vectors of Xylella fastidiosa Wells et al. showed differences among the sampling zones.

Kapateira coffea, Godoy, sp. nov. (Figs. 1���13) Type material: Holotype: male, COSTA RICA: San Jos��: Desamparados, 1200m, 5 ��I�� 2001, C.M. Rodr��guez (CAS). Paratypes: 13 males and 6 females, same data as holotype; 4 male and 7 female, same data except 19 ��I�� 2000; 1 female, same data except 8 ��II�� 2000; 2 males and 3 females, same data except 15 ��II�� 2000; 4 males and 7 females, same data except 21 ��XII�� 2000; 2 females same data except 8 ��II�� 2001; 4 males and 3 females, same data except 12 ��II�� 2001; 2 females, same data except 8 ��III�� 2001; 1 male and 2 females, same data except 19 ��III�� 2001; 1 male and 3 females, same data except 28 ��III�� 2001; 1 male and 2 females, same data except 6 ��IV�� 2001; 2 females, same data except 21 ��XII�� 2001; 1 male and 3 females, same data except 29 ��X�� 2001 (CAS, INBio, BMNH, UCR). Description. Length of male 6.7���7.2 mm, female 6.5���7.4 mm. General color mustard yellow, with black spots or lines on the dorsum of head; pronotum with two spots (Fig. 1). Male genitalia: pygofer with ventral posterior margin rounded, posteriorly produced into short spine on dorsal posterior margin (Fig. 2). Subgenital plate narrowly triangular, extending posteriorly beyond apex of pygofer, with uniseriate macrosetae (Figs. 2, 3). Style extending posteriorly beyond apex of connective, without preapical lobe (Fig. 5). Connective short, Y��shaped (Fig. 4). Aedeagus symmetrical in lateral view with a paired elongate apical processes projecting distally, gonopore located apically, atrium with spine, basal apodemes greatly elongate (Figs. 6, 7). Female sternum VII with ventral surface convex, posterior margin pointed at apex and concave on both sides (Fig. 8). First and second valvulae elongate, slightly wider subapically, tapered to apex. First valvula in lateral aspect wider in apical half and slightly curved, with strigate sculpture on dorsal and apical margins (Fig. 9). Second valvula in lateral aspect with dorsal teeth, individual teeth rounded and slightly elevated (Fig. 10 a���b). Third valvula shorter, narrowed apically to rounded point (Fig. 11). Nymphs (Figs. 12 a���e). Color yellowish, with four distinct longitudinal brown to black stripes. Head large, as long as basal width, crown with anterior portion brown to black; clypeus broad with two longitudinal stripes. Abdominal tergites VI to VIII each with short setae on posterior lateral margins, usually more setae on tergite IX. There are five instars, each resembling the other except for size and the developing wings as shown in Fig. 12 e. The developing wings, in the form of wing pads, become more pronounced in the third, fourth and fifth instars. In these same instars the tibiae have a brown line between setal rows I and II. The nymphs vary from 1.6 to 1.8 mm in length in the first instar, to 6 mm in the fifth instar. Distribution. Known only from Costa Rica. Diagnosis. Kapateira coffea is similar to K. rosipennis but the pygofer has the ventral margin rounded and it is produced into a short spine. Moreover, the aedeagus has paired processes, which is very distinct from the aedeagus of K. rosipennis. Etymology. The specific name refers to the host plant Coffea arabica. Biology. The eggs (Fig. 13) are generally laid in pairs, rarely individually, the two eggs together and in the same position. They are covered with a transparent mucilaginous secretion and are inserted just under the surface of the epidermis, on both the underside and the upperside of the leaf, occasionally on young, nonwoody stems. Each egg is about 2 mm long and yellow. They are fairly difficult to find even with a hand lens, but can be recognized as small, bean��shaped blisters (Fig. 13). The red eye of the developing nymph can be recognized shortly before it hatches. The egg stage lasts about 7 days (n = 10). Immediately after eclosion the nymphs began feeding, generally on the underside of young leaves. The average duration of the first stadium was 11 days (n= 10). Nymphs observed in the process of molting in the laboratory (n= 10), were always located on the undersides of mature leaves on the lower part of the plant. The average duration of the second, third, and fourth stadia was 5 (n= 9), 4.5 (n= 8), and 9.5 days (n= 8), during which time feeding behavior remained the same, except that the fourth and fifth instars began feeding for greater lengths of time on nonwoody stems. The average duration of the fifth stadium was 11 days (n= 6). Of the ten total individuals under observation in the laboratory, one died during the second stadium, one in the third, and two died during the fourth stadium. The adult stage, which lasted about 37.5 days (n= 6), fed on both young and mature leaves. Adults also fed on young stems, on which they remained for most of the day. A total of 120 individuals were tested with DAS��ELISA, and of these 43 were positive for Xylella fastidiosa. This suggests that K. coffea is a potential vector of plant diseases caused by this bacterium, although further tests are needed to determine its actual role in disease transmission. In North America X. fastidiosa has a diverse host range encompassing over 30 families of monocotyledonous and dicotyledonous plants (Purcell and Hopkins, 1996). In Costa Rica this bacterium causes coffee leaf scorch and citrus variegated chlorosis, although the latter seems to occur primarily when citrus is planted in coffee plantations (Rodr��guez, et al. 2001; Aguilar et al. 2005)., Published as part of Godoy, Carolina, Garita-Cambronero, Jerson & Villalobos, Carmen Rivera William, 2006, Two new species of Kapateira Young from Costa Rica (Auchenorrhyncha: Cicadellidae: Cicadellinae), pp. 29-38 in Zootaxa 1282 on pages 31-36, DOI: 10.5281/zenodo.173429, {"references":["Purcell, A. H. & Hopkins, D. L. (1996). Fastidious xylem-limited bacterial plant pathogens. Annual Review of Phytopathology, 34, 131 - 151.","Rodriguez, C. M., Obando, J. J., Villalobos, W., Moreira, L. & Rivera C. (2001). First Report of Xylella fastidiosa Infecting Coffee in Costa Rica. Plant Disease, 85, 1027.","Aguilar, E., Villalobos, W., Moreira, L., Rodriguez, C. M., Kitajima, E. W. & Rivera C. (2005) First Report of Xylella fastidiosa Infecting Citrus in Costa Rica. Plant Disease, 89, 687."]}

Genus Kapateira Young Type Species. Oncometopia rosipennis Osborn (1926 b: 172). Diagnosis. Male 6.7���10.6 mm, female 6.5���7.4 mm. Color dull yellowish. Anterior portion of the pronotum and the scutellum dull yellow, with the disk of the pronotum and the forewing tan to purplish. Some species with black pronotal spots. Head moderately produced, crown with or without a concavity across ocelli, surface without sculpturing or setae. Thorax with pronotal width less than transocular width of head, lateral margins parallel or slightly convergent anteriorly, dorsopleural carinae complete, posterior margin concave; scutellum not transversely rugose. Forewing with membrane including all or almost all apical cells, extending proximally along costal margin or not, with three closed anteapical cells, middle anteapical cell the longest, texture coriaceous with or without weak transverse rugae. Hind femoral setal formula 2: 1: 1, first tarsomere slightly longer than combined length of distal tarsomeres and with two parallel asymmetrical rows of small setae on plantar surface. Male genitalia: Pygofer moderately produced, posterior margin varying from regularly convex to slightly produced posterodorsally and slightly angular, with numerous macrosetae on posterior half of disk, occasionally with interspersed microsetae, pygofer processes absent. Subgenital plate narrowly triangular, variable in their posterior extent compared with apex of pygofer, with uniseriate macrosetae. Style extending posteriorly beyond apex of connective,without preapical lobe. Connective occurring as a transverse bar, or short and Y��shaped. Aedeagus symmetrical, usually with paired processes occurring basally or at apex of shaft, with or without additional processes. Paraphyses usually absent., Published as part of Godoy, Carolina, Garita-Cambronero, Jerson & Villalobos, Carmen Rivera William, 2006, Two new species of Kapateira Young from Costa Rica (Auchenorrhyncha: Cicadellidae: Cicadellinae), pp. 29-38 in Zootaxa 1282 on page 31, DOI: 10.5281/zenodo.173429

Godoy, Carolina, Garita-Cambronero, Jerson, Villalobos, Carmen Rivera William (2006): Two new species of Kapateira Young from Costa Rica (Auchenorrhyncha: Cicadellidae: Cicadellinae). Zootaxa 1282: 29-38, DOI: 10.5281/zenodo.173429

Four agro-food industrial wastes (apple pomace, potato peel, brewers’ spent grain and coffee silverskin) were pretreated with various chemical compounds in order to obtain hydrolysates for ABE fermentation. Sixty-seven potential inhibitors were identified by GC-MS. Then, an HPLC-DAD method was developed and validated for the quantification of the main potential inhibitors identified in the hydrolysates.

Vine shoots (Vitis vinifera L.) were assessed as a feedstock for lactic acid production. Vine shoots were pretreated with acidic or alkaline solutions. The best pretreatment consisted in H2SO4 1.72% (w/w) at 134°C for 17 min, followed by an enzymatic hydrolysis. Three thermotolerant strains, namely Bacillus coagulans DSM 2314, Geobacillus stearothermophilus DSM 2313 and G. stearothermophilus DSM 494, were compared to produce lactic acid from vine-shoot hydrolysates under aerobic and non-sterile conditions, without the need of detoxification steps. In addition, wine lees were satisfactorily employed as nitrogen sources for the fermentation; providing similar results to yeast extract and being the only nutrient added to vine-shoot hydrolysates. Under optimal conditions, B. coagulans DSM 2314 produced 29.21 ± 0.23 g/L lactic acid in 24 h, with a sugar consumption of 98.74 ± 0.07 % and a yield of 96.38 ± 0.76 %, when supplemented with red wine lees.

Corn stover can be efficiently transformed into biobutanol by using low acid concentrations during the physicochemical pretreatment, employing adequate Clostridium strains and performing a detoxification with reusable resins. A broth with 4.75 g/L acetone and 9.02 g/L butanol was obtained. Off-line gas stripping is efficient for butanol recovery from fermentation broths., This document is a pre-print version of the manuscript that was subsequently peer-reviewed and accepted for publication by the journal Renewable Energy (Vol. 148, pages 223-233, year 2020). The final publication is available at Elsevier via https://doi.org/10.1016/j.renene.2019.12.026. This work has been funded by the European Union's Horizon 2020 Research and Innovation Programme (Agrocycle, grant agreement 690142). MH-V is supported by a postdoctoral contract (DOC-INIA, grant number DOC 2013-010) funded by the Spanish National Institute for Agricultural and Food Research and Technology (INIA) and the European Social Fund.

Vine shoots (Vitis vinifera L.) were assessed as a feedstock for lactic acid production. Vine shoots were pretreated with acidic or alkaline solutions. The best pretreatment consisted in H2SO4 1.72% (w/w) at 134��C for 17 min, followed by an enzymatic hydrolysis. Three thermotolerant strains, namely Bacillus coagulans DSM 2314, Geobacillus stearothermophilus DSM 2313 and G. stearothermophilus DSM 494, were compared to produce lactic acid from vine-shoot hydrolysates under aerobic and non-sterile conditions, without the need of detoxification steps. In addition, wine lees were satisfactorily employed as nitrogen sources for the fermentation; providing similar results to yeast extract and being the only nutrient added to vine-shoot hydrolysates. Under optimal conditions, B. coagulans DSM 2314 produced 29.21 �� 0.23 g/L lactic acid in 24 h, with a sugar consumption of 98.74 �� 0.07 % and a yield of 96.38 �� 0.76 %, when supplemented with red wine lees., This study was funded by the European Regional Development Fund (ERDF) within the programme Interreg V-A Espa��a-Portugal (POCTEP) 2014-2020 through the project BIOVINO [0688_BIOVINO_6_E] and also by the H2020-WASTE-2015-two-stage Agrocycle project (Sustainable techno-economic solutions for the agricultural value chain. GA - 690142), funded by the European Union's Horizon 2020 Research and Innovation Programme. This preprint has not undergone peer review or any post-submission improvements or corrections. The Version of Record of this article is published in Applied Microbiology and Biotechnology (2021) 105, 9385-9402, and is available online at https://doi.org/10.1007/s00253-021-11693-1.

Xanthomonas arboricola es una especie de bacterias asociada a plantas. Dentro de la misma se han descrito nueve grupos infraespecíficos o patovares causantes de enfermedad en diversas especies vegetales. Asimismo, se han identificado tanto cepas patógenas como no patógenas que no se incluyen en ninguno de estos grupos. Entre los grupos definidos como fitopatógenos se encuentra X. arboricola pv. pruni, agente causal de la mancha bacteriana de los frutales de hueso y el almendro. Este patógeno de aparición reciente en España, está considerado como organismo de cuarentena en la Unión Europea. En este trabajo se ha caracterizado, tanto molecular como fenotípicamente, una serie de cepas de X. arboricola aisladas de Prunus spp. Un análisis de secuencias multilocus determinó que junto a las cepas de X. arboricola pv. pruni, existían, cohabitando en los mismos huéspedes, algunas cepas de la misma especie que no pertenecían a ninguno de los grupos que se integran en X. arboricola. Además, según la caracterización fenotípica basada en aspectos relacionados con la infección bacteriana, estas cepas no presentaban la capacidad para producir enfermedad en Prunus spp. La caracterización inicial de las cepas de Xanthomonas aisladas de Prunus spp. fue aprovechada para seleccionar una cepa patógena de almendro y otra de ciruelo, CITA 33 e IVIA 2626.1 respectivamente, y tres cepas no patógenas, CITA 14, aislada de P. mahaleb, así como CITA 44 y CITA 124, aisladas de melocotonero. El estudio de genómica comparativa de estas cepas permitió identificar factores que podían estar relacionados con el desarrollo de la enfermedad de la mancha bacteriana de los frutales del género Prunus. El análisis filogenético basado en el “core genome” de la especie, así como un análisis de similitud basado en la presencia de los genes del pan genoma entre las diversas cepas de X. arboricola, permitió corroborar que las cepas no patógenas formaban un grupo filogenético diferente al del patovar pruni, junto con otras cepas de baja virulencia o no patógenas aisladas de diferentes plantas huésped. Además, la comparación de los diferentes genomas permitió encontrar diferencias en los genes relacionados con mecanismos implicados en los estados iniciales de la infección, tales como transportadores TonB-dependientes (TBDTs), sensores del sistema regulador de dos componentes (STCRs) y proteínas aceptoras de grupos metilo (MCPs). Asimismo, se observó en el patovar pruni la presencia de adhesinas no fimbrilares, como FhaB2, que no estaban presentes en las cepas no patógenas. De la misma manera, se encontró variación en cuanto al contenido de genes asociados al pilus tipo IV entre ambos grupos bacterianos. Respecto a la estructura del flagelo, tanto las cepas patógenas como las no patógenas presentaron el mismo perfil en aquellos genes relacionados con su estructura y biogénesis, sin embargo, se observó un cambio en la secuencia de aminoácidos de la proteína flagelina de X. arboricola pv. pruni, la cual podría estar relacionada con la respuesta de la bacteria frente a los mecanismos de defensa de la planta. De igual manera, se encontraron diferencias entre las cepas patógenas y no patógenas en caracteres asociados con etapas tardías de la infección. Una de ellas fue la presencia de diferentes perfiles de genes codificantes de enzimas degradadoras de la pared celular. Otra diferencia encontrada entre ambos grupos de organismos fue la referente al sistema de secreción tipo III y sus efectores. Las cepas patógenas, identificadas como pertenecientes al patovar pruni, presentaron todos los genes asociados a los componentes estructurales y de regulación de este sistema de secreción, así como un total de 21 efectores tipo III. Sin embargo, dos de las cepas no patógenas CITA 44 y CITA 124, no presentaron sistema de secreción tipo III, ni ninguno de los efectores tipo III descritos en Xanthomonas. La cepa no patógena CITA 14 presentó los componentes génicos para un sistema de secreción tipo III funcional pero se identificó solamente un repertorio de seis efectores. Se seleccionó además el gen xopE3, que solamente está presente en el patovar pruni y se desarrolló un protocolo de PCR tiempo real que permitió aumentar la especificidad del protocolo de diagnóstico para la mancha bacteriana de los frutales de hueso y el almendro, al permitir diferenciar de manera específica y sensible las cepas causantes de la enfermedad de aquellas cepas no patógenas que cohabitan los frutales del género Prunus. Este estudio ha permitido conocer una serie de componentes genéticos que podrían estar asociados con el desarrollo de la enfermedad de la mancha bacteriana de los frutales del género Prunus. De la misma manera ha permitido profundizar en el conocimiento sobre la diversidad biológica de X. arboricola y ha generado datos que pueden marcar las pautas de cómo ha podido ser la evolución de la patogenicidad y especificidad de huésped en esta especie de bacterias. Los datos generados han permitido además el desarrollo de un nuevo método de diagnóstico de esta enfermedad más preciso basado en PCR en tiempo real. ABSTRACT Xanthomonas arboricola is a species of plant-associated bacteria, conformed by at least nine infraspecific groups or pathovars. The species encompasses groups of bacteria with diverse plant host range, as well as pathogenic and non-pathogenic strains that does not belong to any of these nine pathovars. Within the plant pathogenic groups, X. arboricola pv. pruni, which is the causal agent of bacterial spot disease of stone fruits and almond, has been recently determined as present in Spain and it is regulated as a quarantine pathogen in the European Union. In this work, a group of Spanish strains of X. arboricola, isolated from Prunus spp. has been characterized using molecular and phenotypic approaches. An initial molecular characterization, conducted by using a multilocus sequence type analysis, determined that there were two groups of strains that cohabited in these hosts. The first one was composed by strains of X. arboricola pv. pruni and the second one by atypical strains that did not belong to any of the nine well-stablished pathovars of X. arboricola. In addition, according to the phenotypic analysis, none of the atypical strains were able to cause disease on Prunus spp. Based on these results, two pathogenic strains of X. arboricola pv. pruni, CITA 33 and IVIA 2626.1, isolated from peach and plum respectively, and three non-pathogenic strains of X. arboricola, CITA 14, isolated from P. mahaleb and CITA 44 and CITA 124, both isolated from peach, were selected for whole genome sequencing. The genome comparative analysis of these strains permitted to find those genomic characters that could be associated with the development of bacterial spot disease of stone fruits and almond. A phylogenetic analysis based in the core genome of X. arboricola as well as a similarity analysis based on the pan-genome of this species, corroborated that the atypical non-pathogenic strains formed cluster which was different to the one composed by the strains of the pathovar pruni. These non-pathogenic strains clustered in a group with other non-pathogenic or low-pathogenic strains isolated from a wide range of plant hosts. Additionally, according to the gene content comparison, variants in the genes related to the different stages of the disease process were found. For instance, both groups showed a different repertoire of genes associated with the sensing of the environmental stimuli, such as those related to the Ton-B dependent transporters (TBDTs), the sensors of the two-component regulatory system (STCRs) and the methyl accepting chemotaxis proteins (MCPs). Beside this, in X. arboricola pv. pruni, some non-fimbrial adhesins, like FhaB2, as well as some components related to the type IV pilus that were absent in the non-pathogenic strains, were found. According to the gene content associated with the flagella structure and regulation, no differences among gene profile of both groups of organisms were elucidated, however, in the pathovar pruni, a variant in the flagellin protein sequence. This variant could be associated with the ability of this bacterial group to avoid the initial steps of the plant defence process. In the same way, variations in the gene content of some key characters related to late stages of the disease process were found. One of the differences was the dissimilar profile of cell wall degrading enzymes between pathogenic and non-pathogenic strains. Moreover, the most important difference observed between these two groups was found in the gene content associated with the type III secretion system and its related effectors. Plant pathogenic strains of X. arboricola pv. pruni harboured all the genetic components related to the structure and regulation of the type III secretion system as well as in a repertoire of 21 type III effectors. Nevertheless, non-pathogenic strains CITA 44 and CITA 124 did not harbour this secretion system or none of the type III effectors described in Xanthomonas. In the case of the non-pathogenic strain CITA 14, this contained all the genes related to a functional type three secretion system but a reduced profile of effectors composed by only six genes was determined. In addition, the gene xopE3, which is present only in X. arboricola pv pruni, was selected and used to design a real-timer PCR protocol which permitted to improve the specificity of the available protocol to identify the bacteria associated to the spot disease of stone fruit and almond. This protocol allowed to perform a specific and sensitive differentiation of the disease-associated strains from those non-pathogenic strains that cohabited on Prunus spp. This study provides a global overview of the genetic components that could be associated with the development of the bacterial spot disease of Prunus. At the same time, it reveals new insights in some other elements of the biology of this bacterial group such as its biological diversity and the potential process associated with the evolution of pathogenicity and host specificity. All the data generated in this investigation has also permitted to develop a new and more accurate real time PCR diagnostic tool for this disease.

La importancia de las enfermedades causadas por bacterias fitopatógenas en España se ha ido incrementando exponencialmente desde la detección, a finales de la década de 1990, de diversas bacteriosis emergentes y reemergentes que han tenido serias repercusiones económicas hasta la detección, desde 2016, de distintos focos deXylella fastidiosaen varias Comunidades Autónomas. Por ello, la Junta Directiva de la Sociedad Española de Fitopatología (SEF) consideró que existía una gran demanda de un libro español de texto o de consulta que recopilara información actualizada sobre estas enfermedades. Este tratado, actualmente único internacionalmente, pretende cubrir ese hueco y ofrecer información proporcionada por 52 expertos bacteriólogos. El libro incluye 48 capítulos que pretenden ofrecer una revisión científica actualizada, pero también realista y práctica, sobre las bacterias fitopatógenas y las enfermedades que ocasionan. Consta de seis capítulos generales introductorios, 13 sobre los géneros de las bacterias seleccionadas y 29 sobre las enfermedades de mayor importancia actual para la agricultura española y también de las que representan una amenaza potencial. La lectura de los distintos capítulos nos lleva a profundizar en el complejo patosistema que constituye cada bacteriosis, su etiología, diagnóstico, epidemiología y control. Cada problema bacteriano se trata con rigor académico, por lo que este texto sirve como fuente básica de conocimiento tanto para profesores como para estudiantes, pero también para técnicos y profesionales de la Sanidad Vegetal, así como para todos los actores que intervienen en la cadena de valor agrícola, desde la producción hasta la comercialización.