The species Pantoea agglomerans includes strains that are agronomically relevant for their growth-promoting or biocontrol traits. Molecular analysis demonstrated that the IPDC pathway involved in the conversion of tryptophan (Trp) to indole-3-acetic acid (IAA) is highly conserved among P. agglomerans strains at both gene and protein levels. Results also indicated that the promoter region controlling the inducible expression of ipdC gene differs from the model system Enterobacter cloacae, which is in accordance with the observation that P. agglomerans accumulates higher levels of IAA when cells are collected in the exponential phase of growth. To assess the potential applications of these microorganisms for IAA production, P. agglomerans C1, an efficient auxin-producer strain, was cultivated in 5 L fermenter so as to evaluate the effect of the medium formulation, the physiological state of the cells, and the induction timing on the volumetric productivity. Results demonstrated that higher IAA levels were obtained by using a saline medium amended with yeast extract and saccharose and by providing Trp, which acts both as a precursor and an inducer, to a culture in the exponential phase of growth. Untargeted metabolomic analysis revealed a significant effect of the carbon source on the exometabolome profile relative to IAA-related compounds and other plant bioactive signaling molecules. The IAA-enriched metabolites secreted in the culture medium by P. agglomerans C1 were used as plant biostimulants to run a series of trials at a large-scale nursery farm. Tests were carried out with in vitro and ex vitro systems following the regular protocols used for large-scale plant tree agamic propagation. Results obtained with 4,540 microcuttings of Prunus rootstock GF/677 and 1,080 plantlets of Corylus avellana L. showed that metabolites from strain C1 improved percentage of rooted-explant, number of adventitious root formation, plant survival, and quality of plant as vigor, with an increase in the leaf area between 17.5 and 42.7% compared to IBA-K (indole-3-butyric acid potassium salt)–treated plants.

Strains belonging to Pantoea agglomerans species are known for their ability to produce metabolites that can act in synergy with auxins to induce the adventitious root (AR) formation. The latter is critically important in the agamic propagation of several woody species, including pear (Pyrus communis L.), playing a considerable role in the commercial nursery farms including those using micropropagation techniques. When grown on a medium amended with tryptophan, the plant-growth-promoting (PGP) strain P. agglomerans C1 produces a cocktail of auxin and auxin-like molecules that can be utilized as biostimulants to improve the rooting of vegetable (Solanum lycopersicum L.) and woody crop species (Prunus rootstock GF/677 and hazelnut). In this study, we evaluated the morphological and molecular responses induced by strain C1 exometabolites in microcuttings of P. communis L. cv Dar Gazi and the potential benefits arising from their application. Results showed that exometabolites by P. agglomerans C1 induced a direct and earlier emergence of roots from stem tissues and determined modifications of root morphological parameters and root architecture compared to plants treated with the synthetic hormone indole-3-butyric acid (IBA). Transcription analysis revealed differences in the temporal expression pattern of ARF17 gene when IBA and C1 exometabolites were used alone, while together they also determined changes in the expression pattern of other key auxin-regulated plant genes. These results suggest that the phenotypic and molecular changes triggered by P. agglomerans C1 are dependent on different stimulatory and inhibitory effects that auxin-like molecules and other metabolites secreted by this strain have on the gene regulatory network of the plant. This evidence supports the hypothesis that the strategies used to harness the metabolic potential of PGP bacteria are key factors in obtaining novel biostimulants for sustainable agriculture. Our results demonstrate that metabolites secreted by strain C1 can be successfully used to increase the efficiency of micropropagation of pear through tissue culture techniques.

The European Construction Sector Observatory outlined that green building envelopes as green roofs and walls contribute to the reduction of energy demand and CO₂ emissions due to the air conditioning in summer periods, and the mitigation of heat islands in urban areas. For this reason, the understanding about the contribution of urban greening infrastructures on buildings to sustainable energy use for air conditioning is urgent. This paper focuses on the analysis of a vertical surface provided with a Parthenocissus quinquefolia (L.) Planch., a winter deciduous species, as green cover of a building, assessing the reduction of the solar radiation energy absorbed by the façade and, consequently, the heat flux (HF) transmitted into the internal ambient. This research shows that, in July, surface temperatures (STs) on the vegetated façade were up to 13 °C lower than on the unvegetated (bare) façade. Under the climate and environmental conditions of the green wall located at ENEA Casaccia Research Center, a saving of 2.22 and 1.94 kWh_e/m², respectively in 2019 and 2020, for the summer cooling electricity load, was achieved. These energy reductions also allowed the saving of 985 and 862 g CO₂/m² emissions, respectively, in 2019 and 2020. Ultimately, a green factor named $K_v^{*}$ was also elaborated to evaluate the influence of vegetation on the STs as well as on HFs transmitted into the indoor ambient and adapted to the case of a detached vertical green cover. Measurements of $K_v^{*}$ factor lasting three years showed the suitability of this index for defining the shading capacity of the vegetation on the building façade surfaces, which can be used to predict thermal gains and effects in a building endowed of a vertical green system.

Current and predicted climate changes scenarios require crops with an improved adaptability to mutable environmental features, such as, hypoxia for the root system. In order to overcome the reduction of oxygen, plants activate coping mechanisms and strategies. Prunus spp. are hypoxia-sensitive woody species and although many information has been gathered over the last decades, many physiological mechanisms remain unclear. To verify whether anoxic plant responses are also regulated by photoperiod, plants of Mr.S.2/5-WT plum, and its variant genotypes S.4 tolerant (plus) and S.1 sensitive (minus) to flooding, were grown in a greenhouse and were submitted to natural photoperiod (NP) and to constant photoperiod (CP) from mid-July until the first 10 days of October. From mid-September plants from each genotype, grown under the two photoperiods, were divided into two groups, and one of them underwent long-term flooding. Gas exchange parameters, energetic and biochemical activities, leaf chlorophyll contents, and stress symptoms were measured at different times, whereas soluble sugars were quantified in leaves and roots 14 days after flooding, when stress symptoms in WT and S.1 became prominent. Seasonal changes in the photoperiod played a role in the adaptability to anoxia, although flooding stress response differed among the three genotypes. Anoxia affected leaf gas exchange and S.4 flooded-leaves retained higher ACO₂ under conditions of NP and CP. Leaf soluble sugar concentration differed among genotypes. Regardless the photoperiod, S.4 anoxic-leaf sugar concentration was the lowest, except for sorbitol. S.4 anoxic-roots under CP accumulated the highest levels of sucrose and sorbitol. Influences of the photoperiod were observed in WT and S.1 anoxic-leaves, whereas S.1 anoxic roots accumulated the lowest concentration of sugars, regardless of photoperiod. Leaf and root respiratory activity in flooded-plants was highest in S.4, and ADH activity increased in all flooded plants under CP but the highest activity was observed only in S.1 under NP during flooding. Results are consistent with the hypothesis that the S.4 genotype has a plastic adaptability to flooding stress, escaping from the photoperiod regulatory cross-talk system, and can better cope with the new scenarios generated by climate changes.

Urbanization poses significant challenges to ecosystems, resources, and human well-being, necessitating sustainable planning. Urban vegetation, particularly trees, provides critical ecosystem services such as carbon sequestration, air quality improvement, and biodiversity conservation. Traditional tree assessments are resource-intensive and time-consuming. Recent advances in remote sensing, especially high-resolution multispectral imagery and object-based image analysis (OBIA), offer efficient alternatives for mapping urban vegetation. This study evaluates and compares the efficacy of Sentinel-2 and Pléiades satellite imagery in classifying tree species within historic urban parks in Rome—Villa Borghese, Villa Ada Savoia, and Villa Doria Pamphilj. Pléiades imagery demonstrated superior classification accuracy, achieving an overall accuracy (OA) of 89% and a Kappa index of 0.84 in Villa Ada Savoia, compared to Sentinel-2’s OA of 66% and Kappa index of 0.47. Specific tree species, such as Pinus pinea (Stone Pine), reached a user accuracy (UA) of 84% with Pléiades versus 53% with Sentinel-2. These insights underscore the potential of integrating high-resolution remote sensing data into urban forestry practices to support sustainable urban management and planning.

Small landscape features (i.e., trees outside forest, small woody features) and linear vegetation such as hedgerows, riparian vegetation, and green lanes are vital ecological structures in agroecosystems, enhancing the biodiversity, landscape diversity, and protecting water bodies. Therefore, their monitoring is fundamental to assessing a specific territory’s arrangement and verifying the effectiveness of strategies and financial measures activated at the local or European scale. The size of these elements and territorial distribution make their identification extremely complex without specific survey campaigns; in particular, remote monitoring requires data of considerable resolution and, therefore, is very costly. This paper proposes a methodology to map these features using a combination of open-source or low-cost high-resolution orthophotos (RGB), which are typically available to local administrators and are object-oriented classification methods. Additionally, multispectral satellite images from the Sentinel-2 platform were utilized to further characterize the identified elements. The produced map, compared with the other existing layers, provided better results than other maps at the European scale. Therefore, the developed method is highly effective for the remote and wide-scale assessment of SWFs, making it a crucial tool for defining and monitoring development policies in rural environments.