José Antonio Manzanera

Phytophthora cinnamomi is a destructive phytopathogen responsible for crown rot, trunk canker, and root rot in over 5,000 plant species worldwide. Despite its significant impact, the molecular interactions between this oomycete and host plants are not well understood. This study aimed to investigate the physiological and molecular responses of Solanum lycopersicum (tomato) to P. cinnamomi infection. The initial defense response in tomato seeds included the production of reactive oxygen species and callose deposition. Screening of commercial tomato varieties revealed varying levels of susceptibility, with the cultivar Marmande exhibiting heightened vulnerability. Three days postinoculation, Marmande showed increased expression of genes associated with reactive oxygen species generation and biosynthesis pathways for phenylpropanoids and flavonoids. Additionally, 850 genes related to cell wall remodeling, including those involved in lignin biosynthesis and pectin methyl esterase inhibitors, were significantly upregulated. Seven days postinoculation, a stronger transcriptional response was observed, with activation of ethylene and jasmonic acid signaling pathways, whereas salicylic acid showed minimal activity. Metabolomic analysis of infected roots revealed elevated levels of metabolites linked to lycopene, flavonoids, and phenylpropanoids. Furthermore, infected roots exhibited a significant reduction in pectin levels, which was corroborated by in vitro assays showing zoospore-mediated pectin degradation. These results suggest that degradation of root pectin is a key mechanism facilitating zoospore invasion in susceptible tomato hosts. This study provides new insights into the molecular mechanisms underlying host–pathogen interactions and identifies potential targets for managing P. cinnamomi-induced diseases in crops. [ ] Copyright © 2025 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Cities play a crucial role in addressing the biodiversity crisis. Despite advancements in urban ecology, effectively integrating biodiversity into urban planning remains limited. Built-environment professionals (BEPs), who are responsible for local actions, often face criticism for their unwillingness to prioritize biodiversity and are seldom studied from their perspectives, especially those from the Global South. Therefore, understanding the viewpoints of diverse BEPs from both the Global South and North on biodiversity-inclusive urban planning and design (BIPD) is crucial. This study employs Q-Methodology to analyze BEPs’ perspectives in Ethiopia, China, Spain, and the United States, revealing four viewpoints: Pluralist, Enthusiast, Pragmatist, and Contextualist. Challenges in realizing BIPD include widespread unawareness among BEPs of existing biodiversity data and methodologies, structural-physical barriers such as land use conflicts and competing resources, and misaligned values with stakeholders. Our research challenges the notion that BEPs resist incorporating biodiversity into their practices by broadly exploring their viewpoints. BEPs exhibit readiness to transcend legislative structural barriers and leverage professional norms to advocate for urban biodiversity, particularly when equipped with evidence-based tools. Pluralists and Enthusiasts demonstrate heightened interest in multidisciplinary collaboration and prescriptive, visual tools to communicate biodiversity’s value to stakeholders. Critically, BEPs’ capacity to act hinges on the availability of contextually sensitive methods, necessitating empowerment through transdisciplinary collaborations to foster transformative changes in cities, especially in the Global South, where complex socioeconomic-ecological trade-offs demand co-produced solutions.

This study investigates the enhanced production of key therapeutic metabolites (ellagic acid, serotonin, and chlorogenic acid) in response to abiotic stress in in vitro cultures of Quercus suber somatic embryos. Findings indicate significant increases in metabolite levels under various stress conditions, highlighting the potential for commercial-scale production of these compounds, known for their antioxidant, anticancer, and anti-COVID-19 properties. Under osmotic/saline stress, ellagic acid production significantly increased, representing an 80% increase compared to control conditions. In embryos exposed to different stressors, serotonin accumulation showed a six-fold increase under osmotic/saline stress. Although the elicitors used did not increase chlorogenic acid levels, exploring alternative stress types may enhance its production. This research paves the way for sustainable, large-scale production of health-beneficial metabolites, addressing global health challenges and promoting resource sustainability.

Aim of study: This study aimed to investigate the biocontrol potential of Bacillus amyloliquefaciens against Phytophthora cinnamomi infection in Quercus suber (cork oak). Both in vitro and in planta experiments were conducted to assess the effectiveness of B. amyloliquefaciens as a biocontrol agent. Area of study: The microorganism strains, B. amyloliquefaciens and P. cinnamomi, as well as the embryogenic lines of Q. suber used, have a Spanish origin. Material and methods: In vitro experiments involved evaluating the inhibitory effects of B. amyloliquefaciens on P. cinnamomi growth through dual-inoculated agar plates. In planta, dual inoculation tests were performed by co-inoculating plantlets with both P. cinnamomi and B. amyloliquefaciens. Physiological parameters, such as photosynthetic activity, chlorophyll content, and oxidative stress markers, were measured. All experiments were conducted under controlled conditions. Main results: In vitro experiments revealed the inhibitory effects of B. amyloliquefaciens on P. cinnamomi growth. Infected plantlets displayed symptoms of root infection. Dual inoculation tests resulted in plant survival against P. cinnamomi infection. Analysis of physiological parameters indicated variations among treatments and clones, highlighting the distinct response of Q. suber plantlets to the pathogen and underscoring the importance of genetic variability for disease management. Research highlights: This study provides insights into the potential of a strain of B. amyloliquefaciens as a biocontrol agent against P. cinnamomi infection in cork oak. Further investigations are warranted to elucidate the underlying mechanisms of susceptibility and resistance in different clones of Q. suber.

This article presents the performance of a vegetation fuel type (FT) classification based on conditional rules according to the Prometheus system, including an analysis of the effect of cell size and scan density on mapping vertical structural types, exemplified as FT, using exclusively LiDAR data. Since the Prometheus system does not specify any criterion for the minimum extension where those methodologies can be applied, we searched for the optimal classification cell size by gridding the study area at 20 and 40 m cell sizes. We also included a study of the effects of varying the scan density from 2 to 0.5 pulses·m-2. To validate the classification method, we used a stratified random sampling without replacement of 15 cells per FT and made an independent visual assessment of FTs. The best results in terms of precision were obtained for the combination of 0.5 pulses·m-2 and 20 m-resolution dataset, with an overall accuracy of 84.13%. It was also showed that an increase in scan density would not improve the global accuracy of the classification, but it would be desirable for a better detection of the shrub stratum.

Airborne Laser Scanning (ALS) is widely extended in forest evaluation, although photogrammetry-based Structure from Motion (SfM) has recently emerged as a more affordable alternative. Return cloud metrics and their normalization using different typologies of Digital Terrain Models (DTM), either derived from SfM or from private or free access ALS, were evaluated. In addition, the influence of the return density (0.5–6.5 returns m^-2) and the sampling intensity (0.3–3.4%) on the estimation of the most common stand structure variables were also analysed. The objective of this research is to gather all these questions in the same document, so that they serve as support for the planning of forest management. This study analyses the variables collected from 60 regularly distributed circular plots (r = 18 m) in a 150-ha of uneven-aged Scots pine stand. Results indicated that both ALS and SfM can be equally used to reduce the sampling error in the field inventories, but they showed differences when estimating the stand structure variables. ALS produced significantly better estimations than the SfM metrics for all the variables of interest, as well as the ALS-based normalization. However, the SfM point cloud produced better estimations when it was normalized with its own DTM, except for the dominant height. The return density did not have significant influence on the estimation of the stand structure variables in the range studied, while higher sampling intensities decreased the estimation errors. Nevertheless, these were stabilized at certain intensities depending on the variance of the stand structure variable.

The main antioxidants present in plant extracts—quercetin, β-carotene, gallic acid, ascorbic acid, hydroxybenzoic acid, caffeic acid, catechin and scopoletin—are able to synthesize silver nanoparticles when reacting with a Ag NO₃ solution. The UV-visible absorption spectrum recorded with most of the antioxidants shows the characteristic surface plasmon resonance band of silver nanoparticles. Nanoparticles synthesised with ascorbic, hydroxybenzoic, caffeic, and gallic acids and scopoletin are spherical. Nanoparticles synthesised with quercetin are grouped together to form micellar structures. Nanoparticles synthesised by β-carotene, were triangular and polyhedral forms with truncated corners. Pentagonal nanoparticles were synthesized with catechin. We used Fourier-transform infrared spectroscopy to check that the biomolecules coat the synthesised silver nanoparticles. X-ray powder diffractograms showed the presence of silver, AgO, Ag₂O, Ag₃O₄ and Ag₂O₃. Rod-like structures were obtained with quercetin and gallic acid and cookie-like structures in the nanoparticles obtained with scopoletin, as a consequence of their reactivity with cyanide. This analysis explained the role played by the various agents responsible for the bio-reduction triggered by nanoparticle synthesis in their shape, size and activity. This will facilitate targeted synthesis and the application of biotechnological techniques to optimise the green synthesis of nanoparticles.

Cork oak (Quercus suber L.) is a forest tree species of the family Fagaceae. It is characterized by long life cycles which hamper doubled haploid plant production to obtain homozygotes and pure lines. The time-consuming method of repeated backcrossings by conventional breeding techniques to produce pure lines is impractical in woody species. Nevertheless, biotechnology has offered new tools to make it possible. A doubled haploid plant or embryo is one that is developed by the doubling of a haploid set of chromosomes. A protocol to produce doubled haploids of cork oak has been developed through microspore embryogenesis. By a heat stress treatment, the microspores inside the anther leave the gametophytic pathway and react shifting their development to the sporophytic pathway by means of which haploid embryos are obtained. Chromosome duplication of haploids from cork oak anther cultures occurs either spontaneously or may be induced by the application of antimitotic agents (e.g., colchicine, oryzalin, amiprophos-methyl). Furthermore, a genetic test is designed through microsatellite markers to elucidate whether the diploid embryos obtained are originally haploids which spontaneously duplicated their genome, or alternatively those embryos are generated from the diploid tissue of the anther wall. Here we describe a detailed protocol to produce doubled haploid individuals from cork oak anther cultures by using temperature stress and antimitotic agents.

Increasing fire size and severity over the last few decades requires new techniques to accurately assess canopy fuel conditions and change over larger areas. This article presents an analysis on vegetation changes by mapping fuel types (FT) based on conditional rules according to the Prometheus classification system, which typifies the vertical profile of vegetation cover for fuel management and ecological purposes. Using multi-temporal LiDAR from the open-access Spanish national surveying program, we selected a 400 ha area of interest, which was surveyed in 2010 and 2016 with scan densities of 0.5 and 2 pulses·m⁻², respectively. FTs were determined from the distribution of LiDAR heights over an area, using grids with a cell size of 20 × 20 m. To validate the classification method, we used a stratified random sampling without replacement of 15 cells per FT and made an independent visual assessment of FT. The overall accuracy obtained was 81.26% with a Kappa coefficient of 0.73. In addition, the relationships among different stand structures and ecological factors such as topographic aspect and forest vegetation cover types were analyzed. Our classification algorithm revealed that stands lacking understory vegetation usually appeared in shady slopes, which were mainly covered by beech stands, whereas sunny areas were preferentially covered by oak stands, where the understory reached greater height thanks to more light availability. Our analysis on FT changes during that 6 year time span revealed potentially hazardous transitions from cleared forests towards a vertical continuum of canopy fuels, where wildfire events would potentially reach tree crowns, especially in oak forests and southern slopes with higher sun exposure for lower fuel moistures and increased flammability. Accurate methods to characterize forest canopy fuels and change over time can help direct forest management activities to priority areas with greater fire hazard. Multi-date canopy fuel information indicated that while some forest types experienced a growth of the shrub layer, others presented an understory decrease. On the other hand, loss of understory was more frequently detected in beech stands; thus, those forests place lower risk of wildfire spread. Our approach was developed using low-density and publicly available datasets and was based on direct canopy fuel measurements from multi-return LiDAR data that can be accurately translated and mapped according to standard fuel type categories that are familiar to land managers.