Symbiotic of Ventenata dubia, Bromus tectorum, Boechera stricta, and Phoenix dactylifera L

Symbiotic of Ventenata dubia, Bromus tectorum, Boechera stricta, and Phoenix dactylifera investigates the intricate nature of plant symbiosis as the relationship between specific plant species (four plant species V. dubia, B. tectorum, B. stricta, and P. dactylifera,) in specific contexts (northwest USA and Saudi Arabia), utilizing laboratory experimental design and literature review methodologies. Symbiosis is a relationship between organisms of different species, and the interaction may be beneficial or harmful. There are three types of symbiotic relationships: mutualism, commensalism, and parasitism. Mutualism is a relationship between organisms of different species with each benefiting. Commensalism is a relationship between organisms of different species without any harm but benefiting one organism and this relationship applies to chapter 3, A bottleneck for microbes in seeds of Ventenata dubia, Bromus tectorum, and Boechera stricta, as endophytes have benefit and no effects on the three-plant species V. dubia, B. tectorum, B. stricta. Endophytes are microorganisms that live in the interior of the plant and have no apparent of damage to their host. Endophytes play essential roles in plant protection, act against herbivores, insects, and pathogens of the host and may even increase plant resistance to pathogens, biotic, and abiotic stresses. Lastly, parasitism involves two organisms, for one benefit and the other, which is considered a host is harmed. For example, plant pathogens cause disease to plants. For example, P. dactylifera (date palm) is parasitized by Aspergillus tubingensis (Chapter 4), and we are setting the groundwork to search for a biological control agent for V. dubia (Chapter 2). The dissertation addresses four plant species that can be categorized as native, introduced, and invasive. Boechera stricta is native to North America and is widespread and has a great potential for studies involving symbiosis. The second category, introduced, is represented by date palm (Phoenix dactylifera L.), intentionally introduced by humans to a new area where it was not previously found. Date palm is native to the arid Arabian Peninsula, North Africa, and the Middle East however to date palm has been introduced to many countries including Australia, India, Pakistan, Mexico, South Africa, and the United States. Dates have been a staple food in the Middle East region for years. Dates are the primary source of income and basic food for the local population in many countries where they are grown and have played essential roles in the economy, society, and environment of those countries. The final relationship involves Ventenata dubia and Bromus tectorum and these two species are invasive. Invasive is defined as a non-native species that changes how an ecosystem functions. Invasive plant species are one of the main and most rapidly developing threats to food security, animal, human health, and biodiversity. The transportation of these invader plants can be through global travel, transport, tourism, and trade, timber products, and ornamental flora. When a new and aggressive species is brought into an ecosystem, it might be in a stage of enemy release leaving all its enemies in their native range, and this helps the invader to spread quickly and to take over an area from the native plants. They can change the plant community by competing with native species in the light, water, or nutrient resources. Invasive plants are threats to native wildlife. Prevention, eradication, and management of invasive species are a costly challenge. For example, in this dissertation V. dubia and B. tectorum are choosen because they are especially damaging the native plants. These two are threatening many of the plant communities in the Pacific Northwest, and they are creating economic and ecosystem losses. The reason to be concerned about losing any native species is that loss of a single species can affect the interconnected in life on earth. If enough ""living connections"" are broken, entire ecosystems in the earth could fail, and balance of nature be forever changed. Additionally, the diversity of animals and plants could change as well, and when species were lost humans would lose the benefits of them as food and medicines forever. European settlers introduced many plants to North America from their homelands, for food, medicinal, ornamental, and other purposes. Introductions of non-native plants continue today, and are even increasing due to elevated worldwide travel and expanded worldwide trade. Many introduced plants have become naturalized over the continent, and a few are replacing North American native plant species. Parallel to overpopulation and global immigration, we also contend with impact from climate change on invasive plant species and an overall change of ecosystems. It is hard to know the immediate measurable effects of climate change because we are uncertain about how the invasive species will respond to diverse parameters of climate change, such as temperature and precipitation. However, there is more than one reason to believe that most climate change will have an impact by increasing the frequency and severity of invasive species in any given geographic region. Invasive species will increase in abundance and emergence because the changing climate becomes unsuitable for the native species. With high nutrition resources, invasive species are well suited to succeed in new environments. Climate change leads to warmer temperatures, and higher CO2 concentration. Severe storms become more common due to climate change and may disperse invasive plant seeds more widely. Presented are four chapters: all chapters are related to the concept of plant symbiosis. All of the four plant species, V. dubia, B. tectorum, B. stricta, and P. dactylifera, have symbiotic relationships with microorganisms. However, each chapter has a different experimental design, and the objectives for each are not the same. The first and second chapters focus on V. dubia, an invasive plant in PNW that is affecting ecosystems by reducing native species abundance and diversity and causing an economic loss in the area infected by V. dubia. The species likely is in a state of enemy release, and thus a biological control would assist in its management. The native range of V. dubia had to be specified so that biological control discovery could be carried out within the native range, and we can look for a control agent. The third and fourth chapters involve symbiosis of the four plants species mentioned above. The third chapter tests a hypothesis of a bottleneck and exclusionary interactions for microbes in seeds of invasive plant species V. dubia, B. tectorum, and native plant species B. stricta and builds on prior research. Experimental design in this chapter was different than Newcombe et al. (2018) to see if this could make any difference. In this experiment, different factors were used: varied age of seed, surface-sterilization protocol, and isolation medium, inoculated versus uninoculated during flowering stage and plant genotypes. The fourth chapter is about date palm seeds and the hypothesis that Aspergillus tubingensis affects the emergence of date palm seedlings. In the beginning, we examined the seeds' endophytes, and we noted that there is an effect of Aspergillus to the seedlings of the date palm and no impact to the seedlings by the other endophytes that were found in the seeds of the date palm. This dissertation’s style is each chapter follow by its references, tables, and figures for better organization. Full credit is given to the dissertation author for tables in chapter 2 synthesizing literature review around V. dubia as all tables were compiled by her.doctoral, Ph.D., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-0

Suppression of Seedling Survival and Recruitment of the Invasive Tree <i>Prosopis juliflora</i> in Saudi Arabia through Its Own Leaf Litter: Greenhouse and Field Assessments

Many studies have focused on how leaf litter depth affects seed germination and seedling growth because the seedling stage is the most vulnerable portion of a plant’s life cycle. Invasive plants with the most severe ecological consequences are those that modify ecosystems, and this can occur through the formation of thick litter layers which can suppress the emergence, survival, and recruitment of native plant seedlings; in addition, in some cases, these litter layers can suppress invasive plant seedling recruitment. Prosopis juliflora is a thorny shrub that is native to arid and semi-arid portions of North America, parts of South America, and the Caribbean. It has invaded millions of hectares around the world, including Saudi Arabia. The objective of this study is to evaluate whether P. juliflora leaf litter reduces the recruitment of its own seedlings under greenhouse and field conditions in Saudi Arabia. In both the greenhouse and the field, the number of days to first emergence increased and germination percentage decreased with increasing litter depth. With the 1, 2, and 4 cm litter depth treatments, the number of viable seeds generally decreased, with no emergence, germination, or viable seeds detected for the 8 cm litter depth treatment. Results of this study reveal that increasing the depth of P. juliflora leaf litter suppresses the survival and recruitment of its own seedlings. Future search should assess the actual mechanisms through which P. juliflora seeds are suppressed, the role of allelopathic compounds in this process, and whether viable seeds are dormant and will persist in the soil seed bank

Exploration of genes encoding KEGG pathway enzymes in rhizospheric microbiome of the wild plant Abutilon fruticosum

Abstract The operative mechanisms and advantageous synergies existing between the rhizobiome and the wild plant species Abutilon fruticosum were studied. Within the purview of this scientific study, the reservoir of genes in the rhizobiome, encoding the most highly enriched enzymes, was dominantly constituted by members of phylum Thaumarchaeota within the archaeal kingdom, phylum Proteobacteria within the bacterial kingdom, and the phylum Streptophyta within the eukaryotic kingdom. The ensemble of enzymes encoded through plant exudation exhibited affiliations with 15 crosstalking KEGG (Kyoto Encyclopaedia of Genes and Genomes) pathways. The ultimate goal underlying root exudation, as surmised from the present investigation, was the biosynthesis of saccharides, amino acids, and nucleic acids, which are imperative for the sustenance, propagation, or reproduction of microbial consortia. The symbiotic companionship existing between the wild plant and its associated rhizobiome amplifies the resilience of the microbial community against adverse abiotic stresses, achieved through the orchestration of ABA (abscisic acid) signaling and its cascading downstream effects. Emergent from the process of exudation are pivotal bioactive compounds including ATP, D-ribose, pyruvate, glucose, glutamine, and thiamine diphosphate. In conclusion, we hypothesize that future efforts to enhance the growth and productivity of commercially important crop plants under both favorable and unfavorable environmental conditions may focus on manipulating plant rhizobiomes

Abundant resistome determinants in rhizosphere soil of the wild plant Abutilon fruticosum

Abstract A metagenomic whole genome shotgun sequencing approach was used for rhizospheric soil micribiome of the wild plant Abutilon fruticosum in order to detect antibiotic resistance genes (ARGs) along with their antibiotic resistance mechanisms and to detect potential risk of these ARGs to human health upon transfer to clinical isolates. The study emphasized the potential risk to human health of such human pathogenic or commensal bacteria, being transferred via food chain or horizontally transferred to human clinical isolates. The top highly abundant rhizospheric soil non-redundant ARGs that are prevalent in bacterial human pathogens or colonizers (commensal) included mtrA, soxR, vanRO, golS, rbpA, kdpE, rpoB2, arr-1, efrA and ileS genes. Human pathogenic/colonizer bacteria existing in this soil rhizosphere included members of genera Mycobacterium, Vibrio, Klebsiella, Stenotrophomonas, Pseudomonas, Nocardia, Salmonella, Escherichia, Citrobacter, Serratia, Shigella, Cronobacter and Bifidobacterium. These bacteria belong to phyla Actinobacteria and Proteobacteria. The most highly abundant resistance mechanisms included antibiotic efflux pump, antibiotic target alteration, antibiotic target protection and antibiotic inactivation. antimicrobial resistance (AMR) families of the resistance mechanism of antibiotic efflux pump included resistance-nodulation-cell division (RND) antibiotic efflux pump (for mtrA, soxR and golS genes), major facilitator superfamily (MFS) antibiotic efflux pump (for soxR gene), the two-component regulatory kdpDE system (for kdpE gene) and ATP-binding cassette (ABC) antibiotic efflux pump (for efrA gene). AMR families of the resistance mechanism of antibiotic target alteration included glycopeptide resistance gene cluster (for vanRO gene), rifamycin-resistant beta-subunit of RNA polymerase (for rpoB2 gene) and antibiotic-resistant isoleucyl-tRNA synthetase (for ileS gene). AMR families of the resistance mechanism of antibiotic target protection included bacterial RNA polymerase-binding protein (for RbpA gene), while those of the resistance mechanism of antibiotic inactivation included rifampin ADP-ribosyltransferase (for arr-1 gene). Better agricultural and food transport practices are required especially for edible plant parts or those used in folkloric medicine

Efficacy and Safety of Tixagevimab/Cilgavimab to Prevent COVID-19 (Pre-Exposure Prophylaxis): A Systematic Review and Meta-Analysis

Background: Tixagevimab/cilgavimab (TGM/CGM) are neutralizing monoclonal antibodies (mAbs) directed against different epitopes of the receptor-binding domain of the SARS-CoV-2 spike protein that have been considered as pre-exposure prophylaxis (PrEP). Objectives: This study seeks to assess the efficacy and safety of TGM/CGM to prevent COVID-19 in patients at high risk for breakthrough and severe SARS-CoV-2 infection who never benefited maximally from SARS-CoV-2 vaccination and for those who have a contraindication to SARS-CoV-2 vaccines. Design: This study is a systematic review and meta-analysis. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Methods: Electronic databases (PubMed, CINAHL, Embase, medRxiv, ProQuest, Wiley online library, Medline, and Nature) were searched from 1 December 2021 to 30 November 2022 in the English language using the following keywords alone or in combination: 2019-nCoV, 2019 novel coronavirus, COVID-19, coronavirus disease 2019, SARS-CoV-2, severe acute respiratory syndrome coronavirus 2, tixagevimab, cilgavimab, combination, monoclonal, passive, immunization, antibody, efficacy, clinical trial, cohort, pre-exposure, prophylaxis, and prevention. We included studies in moderate to severe immunocompromised adults (aged &ge;18 years) and children (aged &ge;12 years) who cannot be vaccinated against COVID-19 or may have an inadequate response to SARS-CoV-2 vaccination. The effect sizes of the outcome of measures were pooled with 95% confidence intervals (CIs) and risk ratios (RRs). Results: Of the 76 papers that were identified, 30 articles were included in the qualitative analysis and 13 articles were included in the quantitative analysis (23 cohorts, 5 case series, 1 care report, and 1 randomized clinical trial). Studies involving 27,932 patients with high risk for breakthrough and severe COVID-19 that reported use of TGM/CGM combination were analyzed (all were adults (100%), 62.8% were men, and patients were mainly immunocompromised (66.6%)). The patients&rsquo; ages ranged from 19.7 years to 79.8 years across studies. TGM/CGM use was associated with lower COVID-19-related hospitalization rate (0.54% vs. 1.2%, p = 0.27), lower ICU admission rate (0.6% vs. 5.2%, p = 0.68), lower mortality rate (0.2% vs. 1.2%, p = 0.67), higher neutralization of COVID-19 Omicron variant rate (12.9% vs. 6%, p = 0.60), lower proportion of patients who needed oxygen therapy (8% vs. 41.2%, p = 0.27), lower RT-PCR SARS-CoV-2 positivity rate (2.1% vs. 5.8%, p &lt; 0.01), lower proportion of patients who had severe COVID-19 (0% vs. 0.5%, p = 0.79), lower proportion of patients who had symptomatic COVID-19 (1.8% vs. 6%, p = 0.22), and higher adverse effects rate (11.1% vs. 10.7%, p = 0.0066) than no treatment or other alternative treatment in the prevention of COVID-19. Conclusion: For PrEP, TGM/CGM-based treatment can be associated with a better clinical outcome than no treatment or other alternative treatment. However, more randomized control trials are warranted to confirm our findings and investigate the efficacy and safety of TGM/CGM to prevent COVID-19 in patients at risk for breakthrough or severe SARS-CoV-2 infection

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population