Many studies have found that future predicted CO2 levels (< 800 ppm) can increase plant mass but dilute N content in leaves, impacting antiherbivore compounds. Nitrogen-fixing plants may balance leaf C:N ratio under elevated CO2, counteracting this dilution effect. The aim of this study was to look at how nitrogen-fixing plants grow and respond to herbivore damage at different CO2 levels. Alnus incana ssp. rugosa was grown at 400, 800, or 1600 ppm CO2 in soil collected from the field, inoculated with Frankia and exposed to herbivores (Orgyia leucostigma). Elevated CO2 increased nodulated plant biomass and stimulated the nitrogen fixation rate in the early growth stage. However, nitrogen-fixing plants were not able to balance the C:N ratio under elevated CO2 after grown 19 weeks. When plant were grown at 400 and 1600 ppm CO2, herbivores preferred to feed on leaves of nodulated plants. At 800 ppm CO2, nodulated plants accumulated more total phenolic compounds in response to herbivore damage than plants in the non-Frankia and non-herbivore treatments. Our results suggest that plant leaf defence, not leaf nutritional content, is the dominant driver of herbivory and nitrogen fixing plants have limited ability to balance C:N ratios at elevated CO2 in natural soil.

Lentil (Lens culinaris Medik.) is an essential legume crop providing healthy and nutritious food for people in low- to middle-income countries, worldwide. Lentil roots support symbiotic interactions with soil rhizobia species fostering nitrogen fixation; however, assemblage and diversity of the complete microbial rhizosphere community and the effect of seed genotype and origin remains largely unexplored. In this study we examined with metagenomic analysis, the effects of seed origin on the rhizosphere’s communities in samples of the famous Greek lentil landrace Eglouvis derived from different local farmers and farming systems including a Gene Bank sample, in comparison to a commercial variety. The landrace exhibited higher rhizosphere microbiome diversity compared to the commercial variety for all indexes. A core microbiome comprised of 158 taxa was present in all samples, while higher number of unique bacterial taxa was recorded in the landrace samples compared to the commercial cultivar. Noteworthy, landrace samples originated from organic farming had more than double unique taxa compared to conventional counterparts. The study revealed higher diversity of N2 fixers and archaea, Crenarchaeota and Thaumarchaeota, in landrace samples and particularly in those derived from organic farming, underpinning the distinct recruiting efficiency of beneficial soil microbes by the landrace.

Vachellia nilotica (L.) Willd. Ex Del. is multipurpose leguminous tree which is common in grass-land and savanna ecosystems in southern and eastern Africa. These ecosystem soils are reported to be acidic and nutrient limited, specifically with regards to nitrogen (N) and phosphorus (P). The presence of this plant in these terrestrial ecosystems improves soil fertility benefiting the sur-rounding vegetation due to its ability fix atmospheric N. This study seeks to understand the mi-crobial symbiosis and physiological adaptations of V. nilotica in these acidic and nutrient defi-cient KZN soils. The soils used for this study were collected from the Ukulinga Grassland Nutri-ent Experiment located at the Ukulinga research farm of the University of KwaZulu-Natal, Pie-termaritzburg, South Africa. Due to long-term soil nutrient addition treatments, these soils of-fered a diverse nutrient variation for better understanding the effects of acidity and nutrient var-iation on microbial symbiosis, plant nutrition and biomass accumulation of V. nilotica. V. nilotica was able to maintain growth by relying on both atmospheric and soil derived N across all treat-ments decreasing carbon (C) growth costs. There was an increased reliance on atmospheric de-rived N of un-nodulated high N treated plants. The plants grown in high N+P soils were able to nodulate with various species from the Mesorhizobium genus which resulted in an increased bio-mass compared to other plants. The results of this study show that V. nilotica can alter N sources to reduce C growth costs. Also, free-living N2 fixing bacteria play an important role under P deficient conditions.

Mobile elevating work platforms (MEWPs) consist of a work platform, extending structure, and chassis, and are used to move persons to working positions. MEWPs are useful but are composed of pieces of equipment, and accidents do occur owing to equipment defects. Among these defects, accidents caused by the fracture of bolts fixed to the extension structure and swing system are increasing. This paper presents a failure analysis of the fixing bolts of MEWP. Standard procedure for failure analysis was employed in this investigation. Visual inspection, chemical analysis, tensile strength measurement, and finite element analysis (FEA) were used to analyze the failure of the fixing bolts. Using this failure analysis approach, we found the root cause of failure and proposed a means for solving this type of failure in the future. First, the chemical composition of the fixing bolt is obtained by a spectroscopy chemical analysis method, which determined that the chemical composition matched the required standard. The tensile test showed that the tensile and yield strengths were within the required capacity. The stress analysis was carried out at five different boom angles, and it was determined that the fixing bolt of MEWP can withstand the loads at all the boom angles. The outcomes of the fatigue analysis revealed that the fixing bolt fails before reaching the design requirements. The results of the fatigue analysis showed primarily that the failure of the fixing bolt was due to fatigue. A visual inspection of the fractured section of the fixing bolt also confirmed the fatigue failure. We propose a method to prevent failure of the fixing bolt of the MEWP from four different standpoints: the manufacturer, safety certification authority, safety inspection agency, and owner.

Endophytic bacteria, especially those participate in nitrogen fixation, play critical roles in supplying essential nutrients for legume plant growth. Compared to the numerous bacterial microbiome reports targeting legume roots and nodules, little is known about embryonic bacteria that facilitate plant nutrient utilization after seed germination. Here, we collected and investigated endophytic bacterial microbiomes in edible pea (Pisum sativum) embryos using five representative cultivars and a pea sprout control. Twenty-six nitrogen-fixing bacteria (NFBs) were isolated from pea embryos, with three strains found in fresh pea (FGP) and snow pea (SP) exhibiting the strongest nitrogenase activity. Some NFB isolates are also potassium-solubilizing bacteria (KSBs) or phosphorus-solubilizing bacteria (PSBs) utilizing inorganic and/or organic phosphorus. All 26 NFBs showed variable levels of indole-3-acetic acid (IAA) secretion. The nutrient-solubilizing NFBs identified in our research are valuable resources for biofertilizer development. At the microbiome level, high-throughput 16S ribosomal RNA (rRNA) sequencing of 40 bacterial collections from pea embryos revealed similar community structures and species abundances and diversities in most samples. Our embryo-derived endophytic bacterial pool provides a microbiome platform for seed dormancy and germination research of edible peas.

Endophytic microbes are a ubiquitous group of plant-associated communities that colonize the intercellular or intracellular host tissues while giving numerous beneficial effects to the plants. All the plant species are thought to be associated with endophytes, majorly constituted with bacteria and fungi. During the last two decades, there has been a considerable movement toward the study of endophytes associated with coffee plants. In this review, the main consideration is given to address the coffee-associated endophytic bacteria and fungi, particularly their action on plant growth promotion and the biocontrol of pests. In addition, we sought to identify and analyze the gaps in available research. Additionally, the potential of endophytes to improve the quality of coffee seeds is briefly discussed. Even though there are limited studies on the subject, it has been well recognized the potentiality of coffee endophytes in plant growth promotion through enhancing nitrogen fixation, availability of minerals, nutrient absorption, secretion of phytohormones, and other bioactive metabolites. Further, the antagonistic effect against various coffee pathogenic bacteria, fungi, nematodes, and also insect pests lead to the protection of the crop. Furthermore, it is recognized that endophytes enhance the sensory characteristics of coffee as a new field of study.

BioPBS is gaining attention in the biodegradable polymer market due to their promising properties such as high biodegradability and processing versatility representing a potential sustainable replacement for fossil oil-based commodities. However, there is still a need to enhance its properties for certain applications, being aesthetical and mechanical properties a challenge. The aim of the present work is to improve these properties by adding selected additives that will confer bioPBS with comparable properties to that of current counterparts such as polypropylene (PP) for specific applications in the automotive and household appliances sectors. A total of thirteen materials have been studied and compared, being twelve biocomposites containing combinations of three different additives: a commercial red colourant, itaconic acid (IA) to enhance colour fixation and zirconia (ZrO2) nanoparticles to maintain at least native PBS mechanical properties. Results show that the combination of IA and the colouring agent tends to slightly yellowish the blend due to the absorbance spectra of IA and also to modify the gloss due to the formation of IA nanocrystals that affects light scattering. In addition, for low amounts of IA (4wt.%), young modulus seems to be kept while elongation at break is even raised. Unexpectedly, a strong aging affect was found after 4 weeks. IA increases the hydrophilic behaviour of the samples and thus seems to accelerate the hydrolisation of the matrix, which is accompanied by an accused disaggregation of phases and an overall softening and rigidization effect. The addition of low amounts of ZrO2 (2wt.%) seems to provide the desired effect for hardening the surface while almost not affecting the other properties; however, higher amounts tends to form aggregates saturating the compounds. As a conclusion, IA might be a good candidate for colour fixing in biobased polymers.