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This study was part of an in vivo investigation of methane (CH4) abatement feed on local Menz breed sheep in Ethiopia, conducted over 90 days period using a randomized complete block design. Sheep were subjected to four dietary treatments: Control, Acacia (Acacia nilotica), BSG (Brewer's Spent Grain), and Ziziphus (Ziziphus spina-christi). The aim of the study was to investigate the rumen microbial community composition, diversity, and their relationships with CH4 intensity. Rumen fluid was collected on days 0 (SD_0), 45 (SD_45), and 90 (SD_90), using an esophageal tube. The dynamics of the bacterial and archaeal domains were assessed by 16S rRNA gene sequencing. The sequencing results showed that 92.9% of ASVs were Bacteria, and 0.05% Archaea. At the genus level, Rikenellaceae RC9 gut group (18%), Prevotella (17%), and Candidatus Saccharimonas (8.9%) were the most abundant Bacteria, while Methanobrevibacter (88%) dominated the Archaeal genera across all treatment groups. Treatment feed significantly altered microbial profiles, notably reducing Methanobrevibacter abundance in CH4 abatement diets and increasing the presence of Methanosphaera. Shannon diversity increased in the abatement diet and decreased when the sheep were fed BSG. CH4 intensity was most strongly associated with the archaeal genus Methanomicrobium, but did not associate strongly with any other Bacteria or Archaea, although Methanobrevibacter and Methanosphaera were correlated negatively (r = –0.97). CH4 intensity also did not covary with volatile fatty acids (VFAs), of which Acacia yielded the highest acetate (772 mmol/mol) and BSG the highest propionate (172 mmol/mol) concentration. The volatile fatty acids (VFAs) showed a strong correlation: a positive correlation between acetate and butyrate (r = 0.80) and a strong negative correlation between acetate and propionate (r = –0.92). These findings highlight the complex relationship between diet, rumen microbiota, and fermentation products, with implications for CH4 mitigation strategies in sheep.

The characterization of the seasonal dynamics of endophytic bacteria in beech leaves can be hindered by co-amplification of chloroplast and mitochondrial plant DNA. This study applies established peptide nucleic acid (PNA) clamps to suppress host-derived amplification while resolving bacterial succession across the vegetative season. Chloroplast- and mitochondrion-specific PNAs inverted the proportion of host to bacterial reads, enabled the recovery of bacterial sequence variants, and increased alpha diversity accordingly. Beta-diversity analyses showed that, once host contamination was removed, samples displayed a clear seasonal trajectory. Early-season leaves contained high abundances of Pseudomonas together with taxa likely introduced through plant–insect–microbe interactions. As leaves matured, the microbiome shifted toward a more stable composition dominated by well-established genera. The transition from early transient taxa to the later enrichment of phyllosphere-adapted and nutrient-cycling genera demonstrates that beech leaves host a temporally structured microbiome shaped by leaf development and seasonal environmental stress.

Accurate profiling of plant-associated fungal and oomycete communities depends critically on the choice of ITS marker. Using Illumina sequencing for ITS1/ITS2 and PacBio HiFi sequencing for full-length ITS (ITSf), we compared read recovery, taxonomic assignment depth, and diversity patterns across potato leaf and root tissues. ITS2 generally recovered more diverse and even community profiles in leaves, whereas ITSf recovered comparatively more even and taxonomically broad profiles in roots. In contrast, ITS1 showed high read recovery but produced strongly skewed compositional profiles and was frequently dominated by host-derived sequences. Beta-diversity analyses indicated that ITS marker choice was associated with substantial variation in observed community composition, while functional annotation highlighted communities composed of taxa associated with multiple ecological guilds, including endophytes and opportunistic pathogens such as Cladosporium and Ilyonectria. Overall, the results demonstrate that ITS marker choice strongly influences the observed structure and diversity of plant-associated communities. ITS2 was generally more suitable for phyllosphere-associated communities, whereas ITSf provided broader recovery of root-associated taxa. Combining complementary markers therefore offers a more comprehensive representation of potato-associated microbial eukaryotic communities than single-marker approaches alone.

Plant growth-promoting rhizobacteria (PGPR) can influence plant development through hormone signalling, nutrient mobil ization, and activation of defence pathways. While individual bacterial strains can enhance plant performance, microbial consortia may generate complementary or synergistic effects that remain poorly understood, particularly with respect to crop developmental signalling. Potato (Solanum tuberosum), the most important dicot food crop globally, represents a suit able model for investigating how beneficial microbes influence tuber development. In this study, we investigated the effects of two well-characterized PGPR strains, Pseudomonas protegens CHA0 and P. simiae WCS417, applied individually or in combination, on two potato cultivars (‘Mandel’ and ‘Désirée’) under long-day conditions. Confocal microscopy confirmed rapid root colonization by both strains within 24 h of inoculation. Metabolomic profiling of bacterial exudates revealed dis tinct metabolic signatures for the two strains and non-additive metabolite patterns when cultured together, suggesting metabolic interactions within the bacterial consortium. Plant responses were cultivar dependent, with bacterial treatments influencing vegetative growth and selected tuber quality traits, including starch and ascorbic acid levels. Gene expression analyses revealed strong induction of the tuberization regulator StSP6A in roots, with up to 5-fold increased expression fol lowing P. protegens and combined inoculation, accompanied by activation of jasmonic acid-related signalling pathways. Together, these results indicate that interactions between beneficial Pseudomonas strains can influence potato develop ment through coordinated effects on root architecture and signalling pathways associated with tuberization and defence.

Potato is the world's third most important food crop, yet its production relies heavily on pesticides, creating a need for sustainable alternatives. We assessed how straw mulching, a practice known to improve soil fertility, enrich microbial activity, and suppress diseases, affects below-ground bacterial community structure and functional potential across different potato-associated sample types. A field experiment was conducted in northern Sweden using two potato cultivars under mulched and control soil conditions. Samples from the rhizosphere, root, soil, and tuber peel were analyzed using 16S ribosomal RNA (rRNA) gene sequencing (Illumina platform) to assess bacterial diversity and community composition. Straw mulching significantly increased bacterial richness and altered community structure across sample types and cultivars. Copiotrophic genera, which thrive in nutrient-rich environments, included Rhodanobacter, Mucilaginibacter, Flavobacterium, and Pseudomonas, and were enriched in rhizosphere, root, and tuber peel. Oligotrophs such as Bryobacter and Candidatus Solibacter dominated the soil and are known to contribute to organic matter turnover and plant growth. Notably, in the peel of one cultivar (King Edward), the abundance of Pseudomonas increased 5–7-fold, correlating with elevated starch and ascorbic acid contents of the tubers. In conclusion, the effect of straw mulching on soil bacterial communities and tuber quality appears to be diverse and cultivar dependent. Long-term and large-scale studies are needed to evaluate cumulative impacts on soil health, yield, and resilience.

Plant growth-promoting rhizobacteria (PGPRs) play a crucial role in enhancing plant development through a variety of direct and indirect mechanisms. These include the production of phytohormones, nitrogen fixation, phosphate solubilization, siderophore-mediated iron acquisition, and biocontrol of plant pathogens. Predominantly inhabiting the rhizosphere, PGPRs interact with plant roots via complex molecular and ecological processes involving signalling molecules, metabolite exchanges, and modulation of plant immune responses. Such interactions enhance nutrient uptake and stress tolerance but also contribute to long-term plant health and productivity across diverse environmental conditions. This review focuses on the genera Pseudomonas and Bacillus, which are extensively studied for their strong colonization abilities, metabolic versability, and demonstrated potential in improving crop resilience. Advances in microbial genomics, metagenomics, and high-throughput phenotyping have greatly enhanced our ability to identify, characterize, and apply beneficial microbes across a range of crop systems. However, key challenges remain, including limited understanding of native soil microbiotas, the functional outcome of microbiome-soil-plant interactions, and the development of agricultural practices that efficiently integrate microbial solutions. With potato (Solanum tuberosum) as a model crop, this review synthesizes current knowledge on PGRP-mediated growth promotion - primarily by Pseudomonas and Bacillus acting alone or in microbial consortia, identifies critical research gaps, and outlines future directions for the application of PGPRs in sustainable crop production.

Based on discussions within the Northern Tubers of Potato network (N’TOP-net), this review highlights northern Scandinavia’s potential for sustainable, low pest seed potato production. While long transport distances currently limit large-scale supply for consumption or processing, low pest pressure and stricter EU plant protection regulations increase its value for seed production. Climate change is expected to extend the growing season, driving renewed interest in Northern Scandinavia’s role in European food security. Finland exemplifies this potential, and parts of northern and central Sweden—historically suppliers of disease-free seed potatoes, even exported to Brazil—offer expansion opportunities. Nordic potato production, key biotic stressors, and opportunities for regional cooperation are examined, with a focus on novel farming practices, breeding innovations, and disease surveillance to improve resilience and sustainability. Despite shared values in cultivar selection, certification, and potato preferences, Nordic production strategies remain uncoordinated for long-term sustainability. We advocate for transnational, interdisciplinary collaboration to enhance Europe’s food security through joint efforts in three key areas: (1) soil-conserving farming, (2) breeding for adaptation to longer day length and resistance traits, and (3) transnational pest and disease surveillance. A Nordic potato initiative can strengthen European cooperation on sustainable production amid climate change. However, as policies must balance the benefits of longer growing seasons with emerging risks such as pests, droughts, and flooding, coordinated research, regulatory adaptation, and climate resilience investments are essential for safeguarding seed potato quality, food security, and supply chain stability.

The study evaluates the impact of two metal oxide nanoparticles: copper oxide (CuO) and zinc oxide (ZnO) on the growth and physiology of Raphanus sativus L. (radish) under salinity stress. Fifteen days old seedlings of R. sativus were subjected to different concentrations of salt stress (0 mM, 150 mM, and 300 mM NaCl) alone and in interaction with 100 mgL−1 metal oxide nanoparticle treatments (CuO and ZnO NPs via foliar spray) for 15 days. The results confirmed the severe effects of salinity stress on the growth and physiology of radish plants by decreasing nutrient uptake, leaf area, and photosystems photochemistry and by increasing proline accumulation, anthocyanin, flavonoids content, and antioxidant enzyme activities which is directly linked to increased oxidative stress. The foliar application of CuO and ZnO NPs alleviated the adverse effects of salt stress on radish plants, as indicated by improving these attributes. Foliar spray of ZnO NPs was found efficient in improving the leaf area, photosynthetic electron transport rate, the PSII quantum yield, proton conductance and mineral content in radish plants under NaCl stress. Besides, ZnO NPs decreased the NaCl-induced oxidative stress by declining proline, anthocyanin, and flavonoids contents and enzymatic activities such as superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (GOPX). Thus, our study revealed that ZnO NPs are more effective and have beneficial effects over CuO NPs in promoting growth and reducing the adverse effects of NaCl stress in radish plants.

In modern agriculture, nano-priming represents an innovative approach, harnessing the power of nanotechnology to enhance crop yields and nutrition. However, to effectively harness the potential of nanoparticles (NPs) for agriculture applications, understanding their mode of action and optimal application rates for positive effects on microgreen growth and physiology is critical. In this interdisciplinary study, we investigated the priming of sunflower seeds with a range of concentrations (25, 50, and 100 mg/L) of ferric oxide (Fe2 O3) nanoparticles (FeNPs) and compared them with control samples. Our findings revealed a significant increase in plant biomass, leaf size, and photosynthetic activity in treated samples. The activities of photosystems I and II increased with higher FeNPs concentration. The treated samples exhibited elevated levels of total phenolics, anthocyanin, and antioxidant enzyme activity, along with increased macronutrients and micronutrients. These findings highlight the potential of FeNPs as a promising tool for enhancing plant growth and physiology in sunflower microgreens.

The present study evaluated the repercussions of magnetopriming on the root system architecture of soybean plants subjected to arsenic toxicity using synchrotron radiation source based micro-computed tomography (SR-µCT). This will be used evey where as abbreviation for the technique for three-dimensional imaging. Seeds of soybean were exposed to the static magnetic field (SMF) of strength (200 mT) for 1h prior to sowing. Magnetoprimed and non-primed seeds were grown for 1 month in a soil-sand mixture containing four different levels of sodium arsenate (0, 5, 10, and 50 mg As kg⁻¹ soil). The results showed that arsenic adversely affects the root growth in non-primed plants by reducing their root length, root biomass, root hair, size and number of root nodules, where the damaging effect of As was observed maximum at higher concentrations (10 and 50 mg As kg⁻¹ soil). However, a significant improvement in root morphology was detected in magnetoprimed plants where SMF pretreatment enhanced the root length, root biomass, pore diameter of cortical cells, root hair formation, lateral roots branching, and size of root nodules and girth of primary roots. Qualitative analysis of x-ray micro-CT images showed that arsenic toxicity damaged the epidermal and cortical layers of the root as well as reduced the pore diameter of the cortical cells. However, the diameter of cortical cells pores in magnetoprimed plants was observed higher as compared to plants emerged from non-primed seeds at all level of As toxicity. Thus, the study suggested that magnetopriming has the potential to attenuate the toxic effect of As and could be employed as a pre-sowing treatment to reduce the phytotoxic effects of metal ions in plants by improving root architecture and root tolerance index. This study is the very first exploration of the potential benefits of magnetopriming in mitigating the toxicity of metals (As) in plant roots utilizing the micro-CT technique.