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1.- Introducción Los cítricos, originarios del sureste asiático, pertenecen al orden Geraniales, familia Rutaceae y subfamilia Aurantioideae. Dentro de esta subfamilia, los cítricos de mayor importancia económica se engloban dentro de la tribu Citreae, subtribu Citrinae, grupo Cítricos Verdaderos, género Citrus y subgénero Eucitrus. Hoy en día los cítricos se cultivan en la mayor parte de las regiones tropicales y subtropicales del planeta con un total de 161,8 millones de toneladas, siendo España el quinto país productor (6,7 mills t) a nivel mundial y el primer productor de la Unión Europea. España destaca también como primer país exportador de cítricos para consumo en fresco (3,6 mills t). En España, Andalucía se sitúa como la segunda Comunidad Autónoma productora de cítricos (2,7 mills t), con un claro predominio del cultivo del naranjo dulce (69,58 % de la superficie de cítricos), seguido del de mandarino (21,40 %), limón (7,46 %), pomelo (0,93 %) y otros cítricos (0,28 %). El cultivo de los cítricos en Andalucía se presenta como un sector agrario de gran importancia territorial (83.180 ha), económica (844 mills euros) y social (5,9 mills jornales). Los nuevos desafíos a los que se enfrenta la citricultura española en general, como consecuencia del incremento de la población mundial, el cambio climático, la globalización, los nuevos gustos del consumidor y los nuevos compromisos europeos en materia de sostenibilidad, requieren del desarrollo e implementación de nuevas tecnologías que permitan una citricultura más competitiva, resiliente y sostenible. Ante esta situación, la intensificación sostenible del cultivo se presenta como una estrategia de gran interés, en la que se identifican tres pilares fundamentales: la adecuada elección del patrón, la mayor densidad de plantación y la mecanización del cultivo. En este sentido, adquiere una gran importancia el estudio de nuevos patrones de cítricos compatibles con este nuevo modelo de producción: patrones de reducid

Citriculture is considered the most important fruit industry and involves the cultivation of several fruit varieties, which are susceptible to many plant pathogens. In this sense, soil-borne pathogenic fungi, such Rosellinia necatrix, threaten citrus fruit production worldwide because they can cause fruit loss. Therefore, we assayed the physiological reaction of novel citrus rootstocks against white root rot disease during long-term management. Data from above-ground symptoms and chlorophyll content were periodically obtained during the experimental process. In addition, plant leaf area and percentage of biomass reduction were determined for each rootstock when the experiment finished. The behavior of the inoculated tolerant rootstocks was as follows: the lowest symptom rate of SAUDPC was achieved by B11R5T25 and N40R3T25; AMB+CZO manifested the highest disease incidence; B11R5T25 and A+VOLK × Orange 19-11-8 displayed the highest and the lowest chlorophyll content, respectively; AMB+CZO and A+VOLK × Orange 19-11-8 showed the highest biomass reduction, and the lowest was detected in B11R5T25 and N40R2T19; concerning the leaf area, N40R1T18, N40R3T25 and N40R2T19 showed the lowest response, and 2247 × 2075-01-2 achieved the highest rate. In summary, B11R5T25 and N40R3T25 displayed the lowest disease rate.

[Abstract] Intertidal communities have been extensively studied for decades. Many of these studies have focused on macroalgae, as they are key components of many rocky coastal ecosystems. Despite this, there are still regions of the world where there is a lack of knowledge of intertidal macroalgal communities. This is the case in some tropical regions, such as the Cape Verde archipelago, located on the tropical west coast of Africa. To contribute to the knowledge of the macroalgal communities of this region, during July 2022, we studied the distributional pattern and zonation of macroalgal communities along the rocky intertidal of Santo Antão Island, the northernmost island of the archipelago and the least studied. Using a nested design, we compared the macroalgal assemblages of six rocky shores along the entire coastline, including three sites per shore, and four quadrats per site and tidal level. We found 43 macroalgal species – 29 Rhodophyta, 12 Ochrophyta, 2 Chlorophyta – and one Cyanobacteria. The orders Ceramiales, Corallinales, and Gigartinales were the groups more represented, followed by Ectocarpales and Dictyotales. The upper intertidal was dominated by brown algae, while red algae dominated the middle intertidal. Green algae had a scarce presence in both tidal levels. Our results found no differences between the north and south of the island but between rocky shores and tidal levels. Our results provide for the first time comprehensive information on the seaweed community structure, zonation patterns, and a comparison of seaweed abundances in a vertical and horizontal gradient along the entire rocky shores of Santo Antão Island. In the face of the current climate change, our data can be the baseline for future work on algal communities in this región.

Los contenidos prácticos constituyen una parte fundamental del programa de la asignatura Propagación Vegetal, impartida en la Escuela Técnica Superior de Ingeniería Agronómica (Universidad de Sevilla), y representan cuatro créditos de un total de seis. Con ellos se pretende consolidar y aplicar los conocimientos teóricos, practicar determinadas técnicas y posibilitar al alumno el desarrollo de destrezas en el manejo de materiales y herramientas propias de los trabajos de obtención de plantas. Con estos objetivos y teniendo en cuenta la disponibilidad de tiempo y medios, se ha diseñado un programa de prácticas que incluye especies hortícolas, frutales, ornamentales y forestales, así como técnicas relacionadas con un amplio número de métodos de propagación

Citrus is one of the most important fruit crops in Mediterranean countries such as Spain, which is one of the main citrus-producing countries worldwide. Soil-borne pathogens, such as Rosellinia necatrix, are relevant limiting biotic factors in fruit trees, due to their tricky management. This fungus is a polyphagous plant pathogen with worldwide distribution, causing white root rot in woody crops, including citrus trees in Spain. The objective of this study was to evaluate the tolerance of new plant material against R. necatrix infection. Therefore, plants of 12 different citrus rootstocks were inoculated with one R. necatrix isolate. During the assay, and periodically, above-ground symptoms and chlorophyll content were evaluated. At the end of the experiment, leaf area and plant biomass measures were obtained. Rootstocks B11R5T64 and B11R5T60 achieved the lowest disease incidence of symptoms and reduction of biomass, and were similar to their respective controls in chlorophyll content and leaf area. Carrizo citrange, CL-5146 and UFR-5 were the most affected rootstocks in symptoms and biomass reduction. This work provides information about R. necatrix-tolerant citrus rootstocks, which can constitute a new integrated, sustainable and effective long-term strategy to avoid white root rot.

Novel species of fungi described in this study include those from various countries as follows: Australia, Agaricus albofoetidus, Agaricus aureoelephanti and Agaricus parviumbrus on soil, Fusarium ramsdenii from stem cankers of Araucaria cunninghamii, Keissleriella sporoboli from stem of Sporobolus natalensis, Leptosphaerulina queenslandica and Pestalotiopsis chiaroscuro from leaves of Sporobolus natalensis, Serendipita petricolae as endophyte from roots of Eriochilus petricola, Stagonospora tauntonensis from stem of Sporobolus natalensis, Teratosphaeria carnegiei from leaves of Eucalyptus grandis × E. camaldulensis and Wongia ficherai from roots of Eragrostis curvula. Canada, Lulworthia fundyensis from intertidal wood and Newbrunswickomyces abietophilus (incl. Newbrunswickomyces gen. nov.) on buds of Abies balsamea. Czech Republic, Geosmithia funiculosa from a bark beetle gallery on Ulmus minor and Neoherpotrichiella juglandicola (incl. Neoherpotrichiella gen. nov.) from wood of Juglans regia. France, Aspergillus rouenensis and Neoacrodontium gallica (incl. Neoacrodontium gen. nov.) from bore dust of Xestobium rufovillosum feeding on Quercus wood, Endoradiciella communis (incl. Endoradiciella gen. nov.) endophytic in roots of Microthlaspi perfoliatum and Entoloma simulans on soil. India, Amanita konajensis on soil and Keithomyces indicus from soil. Israel, Microascus rothbergiorum from Stylophora pistillata. Italy, Calonarius ligusticus on soil. Netherlands, Appendopyricularia juncicola (incl. Appendopyricularia gen. nov.), Eriospora juncicola and Tetraploa juncicola on dead culms of Juncus effusus, Gonatophragmium physciae on Physcia caesia and Paracosmospora physciae (incl. Paracosmospora gen. nov.) on Physcia tenella, Myrmecridium phragmitigenum on dead culm of Phragmites australis, Neochalara lolae on stems of Pteridium aquilinum, Niesslia nieuwwulvenica on dead culm of undetermined Poaceae, Nothodevriesia narthecii (incl. Nothodevriesia gen. nov.) on dead leav

Desert truffle is becoming a new crop in semiarid areas. Climatic parameters and the presence of microorganisms influence the host plant physiology and alter desert truffle production. Desert truffle plants present a typical summer deciduous plant phenology divided into four stages: summer dormancy, autumn bud break, winter photosynthetic activity, and spring fruiting. We hypothesize that the bacterial community associated with desert truffle plants will show a seasonal trend linked to their plant growth–promoting rhizobacteria (PGPR) traits. This information will provide us with a better understanding about its potential role in this symbiosis and possible management implementations. Bacteria were isolated from root-adhering soil at the four described seasons. A total of 417 isolated bacteria were phenotypically and biochemically characterized and gathered by molecular analysis into 68 operational taxonomic units (OTUs). They were further characterized for PGPR traits such as indole acetic acid production, siderophore production, calcium phosphate solubilization, and ACCD (1-amino-cyclopropane-1-carboxilatedeaminase) activity. These PGPR traits were used to infer functional PGPR diversity and cultivable bacterial OTU composition at different phenological moments. The different seasons induced shifts in the OTU composition linked to their PGPR traits. Summer was the phenological stage with the lowest microbial diversity and PGPR functions, whereas spring was the most active one. Among the PGPR traits analyzed, P-solubilizing rhizobacteria were harbored in the mycorrhizosphere during desert truffle fruiting in spring.