The use of natural-origin biomaterials in bioengineering has led to innovative approaches in agroforestry. Bacterial cellulose (BC), sharing the same chemical formula as plant-origin cellulose (PC), exhibits significantly different biochemical properties, including a high degree of crystallinity and superior water retention capacity. Previous research showed that natural-origin glucose-based chitin enhanced plant growth in both herbaceous and non-herbaceous plants. In this study, we produced BC in the laboratory and investigated its effects on the substrate and on Solanum lycopersicum seedlings. Soil amended with BC increased root growth compared with untreated seedlings. Additionally, under limited irrigation conditions, BC increased global developmental parameters including fresh and dry weight, as well as total carbon and nitrogen content. Under non-irrigation conditions, BC contributed substantially to plant survival. RNA sequencing (Illumina^®) on BC-treated seedlings revealed that BC, despite its bacterial origin, did not stress the plants, confirming its innocuous nature, and it lightly induced genes related to root development and cell division as well as inhibition of stress responses and defense. The presence of BC in the organic substrate increased soil availability of phosphorus (P), iron (Fe), and potassium (K), correlating with enhanced nutrient uptake in plants. Our results demonstrate the potential of BC for improving soil nutrient availability and plant tolerance to low irrigation, making it valuable for agricultural and forestry purposes in the context of global warming.

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 .

The 21st century presents significant challenges for agriculture, including the adoption of more efficient and sustainable production methodologies and adaptation to climate change. Climate change is altering local climatic conditions, impacting forestry and agriculture, and potentially exacerbating desertification by disrupting patterns of solar radiation, and winds. This could lead to a reduction of 30,000 km² in the country's forested area over 60 years. Water availability is also closely tied to climate change, affecting precipitation and temperature patterns and aquatic ecosystems, resulting in algal blooms and water eutrophication. This Industrial PhD is marked applied corresponding to I+D+i projects for developing three products: the first is enhanced ZOIBAC®, composed of a microbial consortium; the second is BIO100®, and the third is B2P. Their development was focused on improving the fertilizing capacity of livestock waste, controlling algal growth, exerting a positive effect on soils, enhancing vegetative vigour, and increasing stress tolerance. Improved ZOIBAC® was applied to livestock slurry, achieving substantial quality improvements on slurry. ZOIBAC® reduced toxicity by decreasing the content of N, P, K, and heavy metals. This was confirmed using Lolium perenne (Lp), where treated slurry (TS) showed no phytotoxic effects on germination, unlike untreated slurry. TS demonstrated strong bio-fertilizing capacity, enhancing vegetative growth, biomass, and carbon and nitrogen content. The physiological effect of BIOPROD was assessed on Lp in hydroponic conditions, revealing no adverse effects. BIOPROD effects were assessed in desert-Martian-like substrates (DMLS), showing that DMLS negatively impacted germination, but the bioproduct application positively influenced germination without affecting growth. BIO100® was developed to prevent algal growth in irrigation water. Its efficacy in eliminating algae was confirmed, and it had no negative impact on Lp growth. The physiological and molecular effects of one cellulose of bacterial origin (CelB) were studied in Sl under hydroponic and micro-pot systems with standard and DMLS. CelB was found to be beneficial, inducing genes related to plant development. The treatment increased Sl biomass, substrate water content, and the bioavailability of elements essential for plant growth. One of the biopolymers assessed in this PhD was chitin. The chitin applied in micro-pot systems with standard substrate and DMLS revealed enhanced aerial growth and chlorophyll content and increased bioavailability of plant-beneficial compounds. B2P positively affected plant growth (aerial and root biomass) in both micro-pot and greenhouse conditions. The treatment increased the number of definitive leaves, leaf area, and photosynthetic pigment content. Additionally, massive soil microbiome sequencing revealed that the bioproduct application induced changes in microbiome structure and abundance, promoting increases in the presence of Actinobacteria and Proteobacteria. Three effective bioproducts were developed: the first for livestock slurry treatment, the second for irrigation water treatment, and the third for improving soil quality and plant growth. RESUMEN El siglo XXI presenta importantes desafíos para la agricultura, incluyendo la adopción de metodologías de producción más eficientes y sostenibles, así como la adaptación al cambio climático. Este último está alterando las condiciones climáticas locales, impactando la silvicultura y la agricultura, y exacerbando la desertificación al modificar los patrones de radiación solar y vientos. Esto ha conducido a una reducción de 30,000 km² en la superficie forestal del país en los últimos 60 años. La disponibilidad de agua también está estrechamente vinculada al cambio climático, afectando los patrones de precipitación y temperatura, así como los ecosistemas acuáticos, lo que resulta en floraciones de algas y eutrofización del agua. Este Doctorado Industrial está enmarcado en proyectos de I+D+i destinados al desarrollo de tres productos el primero es ZOIBAC® mejorado formado por un consorcio microbiano, el segundo es BIO100®, y el tercero es B2P. Su desarrollo perseguía la mejora de la capacidad fertilizante de los residuos ganaderos, del control del crecimiento de algas, ejercer un efecto positivo en los suelos, mejora del vigor vegetativo e incremento de la tolerancia al estrés. Se aplicó ZOIBAC® mejorado a purines de ganadería, logrando mejoras sustanciales en la calidad del purín. ZOIBAC® redujo la toxicidad al disminuir el contenido de N, P, K y metales pesados. Esto se confirmó mediante ensayos con Lolium perenne (Lp), donde los purines tratados (PT) no mostraron efectos fitotóxicos en la germinación, a diferencia de los purines no tratados. PT demostró una alta capacidad biofertilizante, mejorando el crecimiento vegetativo, la biomasa y el contenido de carbono y nitrógeno. Se evaluó el efecto fisiológico de BIOPROD sobre Lp en hidroponía, sin encontrar efectos adversos. Los efectos de BIOPROD fueron probados en sustratos desérticos tipo marciano (DMLS), mostrando que Los DMLS afectaban negativamente la germinación, pero la aplicación del bioproducto mejoró la germinación sin afectar el crecimiento. BIO100® se desarrolló para prevenir el crecimiento de algas en aguas de riego. Se confirmó su eficacia para eliminar algas y no generó impacto negativo en el crecimiento de Lp. Los efectos fisiológicos y moleculares de celulosa de origen bacteriano (CelB) se estudiaron en Solanum lycopersicum (Sl) en sistemas hidropónicos y de micromaceta con sustrato estándar y DMLS. Se encontró que CelB era...