Biologia futura最新文献

Biotic stress, particularly from fungal diseases, significantly impedes agricultural productivity worldwide. To meet the increasing demand for sustainable food production, environment-friendly and cost-effective solutions are needed. Plant growth-promoting rhizobacteria (PGPR) provide a sustainable alternative by enhancing plant health and acting as biocontrol agents. This study aimed to investigate the genetic diversity and biocontrol potential of biotic stress-tolerant rhizobacteria isolated from the rhizosphere of cotton and wheat plants infected with fungi in a cotton-wheat rotation area. A total of 136 rhizobacteria were isolated and screened for their in-vitro antifungal activity against Fusarium oxysporum. Among these, 108 isolates demonstrated antifungal activity against F. oxysporum. Additionally, various biocontrol-linked traits were assessed, including hydrogen cyanide (HCN) production, starch hydrolysis, exopolysaccharide (EPS) production, enzyme production (pectinase, protease, gelatinase, catalase) and biofilm formation. The results showed that 88 isolates exhibited pectinase activity, 105 showed biofilm formation and EPS production, 20 demonstrated protease production, 93 showed starch hydrolysis activity. Only three isolates produced hydrogen cyanide. Gelatinase activity was observed in 124 isolates, while catalase activity was detected in 87 isolates. Genetic diversity analysis of the tolerant rhizobacteria was performed using REP, ERIC, and (GTG)₅-PCR fingerprinting. The dendrogram constructed from (GTG)₅ and REP-PCR fingerprint profiles indicated greater diversity. Moreover, all three PCR-primers effectively differentiated the cotton rhizosphere isolates from those obtained from the wheat rhizosphere, indicating a distinct resident bacterial community despite the cotton-wheat rotation. These findings suggest the presence of diverse, biotic stress-tolerant rhizobacteria in the cotton-wheat rotation area, which could be utilized as potential biocontrol agents against fungal plant diseases. However, further research is required to explore the pathways underlying their antifungal potential and to develop sustainable and efficient bio-formulations for field applications.

Monitoring the root system plays an important role in understanding plant physiological processes; however, its assessment using non-destructive methods remains challenging. Here, we evaluate the utility of root capacitance (C_R) as a practical indicator of root function and its relationship to plant growth parameters in Capsicum annuum L. To improve the accuracy of root function assessment, we applied artificial neural networks (ANN) as a novel data evaluation approach, comparing its predictive performance against multiple linear regression (MLR). Across two soil types (sandy and sandy loam), we applied multiple treatments ranging from microbial inoculants to wool pellet and inorganic nitrogen sources primarily to test whether C_R could detect differences in root activity and biomass production under different conditions. We measured root dry biomass, shoot dry biomass, and leaf N content, treating these variables as independent predictors in a statistical framework. Multiple linear regression (MLR) initially showed strong relationship between C_R and both root and shoot biomass in sandy soil, and between C_R and total plant N content in sandy loam. However, an ANN model consistently outperformed MLR in predicting C_R from plant physiological parameters, as evidenced by lower mean absolute error (MAE) in all treatments. These findings confirm that C_R correlates strongly with plant growth parameters and can reliably distinguish the effects of different soil amendments even those with markedly different nutrient-release profiles.

Pellets made from waste wool, typically sourced from sheep shearing residues generated by the textile or wool industry, have recently emerged as a promising alternative for plant nutrition. However, limited information is available on the impact of wool pellets (WP), applied at a dosage of 4 g per pot, on soil functioning, biological activity, plant physiology, and nutrient supply. A pot experiment was set up in a randomized block design with four replicates on sweet peppers (Capsicum annuum L.). The effect of WP on permanganate-oxidizable carbon, fluorescein diacetate, and β-glucosidase enzyme activities were investigated in two soils differing in their soil organic matter (SOM) contents (low and high) and compared to the control and a reference N fertilizer solution. The nitrate and total nitrogen content of plants, the photosynthetic pigments, gas exchange intensity, shoot and root biomass, pepper fruit, and photosynthetic rate per total N-uptake were also examined. WP treatments (4 g per pot) increased soil biological activity in both soil types (with 0.58% and 1.84% soil organic matter, respectively) and significantly improved plant physiological parameters and N-use efficiency compared to the control and reference N fertilizer addition. Although the total N content in wool pellets was higher than in the mineral reference N-solution, this reference treatment served as a baseline dose allowing comparison with the N-supply intensity of the WP. WP significantly increased shoot biomass in both soil types, with a more pronounced effect in the low SOM soil due to faster mineralization and higher air capacity. In contrast, higher fruit was achieved in the high SOM soil. WP treatment increased N-uptake to 2.18 and 2.34 mg/week in low and high SOM, respectively. The research findings highlight wool pellets as a powerful alternative to inorganic fertilizers, offering a sustainable nutrient supply. Moreover, utilizing wool a by-product often considered waste as an organic fertilizer contributes to solving both economic and environmental challenges associated with wool disposal.

Calcipaenic bone disorders (e.g., osteoporosis) are becoming an epidemic as a significant public health concern. The underlying genetic, epigenetic, and homeostatic factors and the determinants of bone tissue expression are triggered by environmental exposures. Endocrine disruptor compounds are important in the development of pathological bone alterations. The aim of this study is to design an in vivo subtoxic chlorobenzene exposure model that can be used to explore certain bone changes and their consequences. Male Wistar rats were treated via gastric tube with a 1:1 mixture of hexachlorobenzene + 1,2,4-trichlorobenzene at a dose of 1.0 μg/kg bw; in a final volume of 1 mL, for 30, 60 and 90 days. Blood serum and bone samples were obtained from the femur diaphysis. The results of the treatments (n = 10/group) were interpreted as related to the controls. Serum levels of γGT, SGOT, SGPT were determined, along with bone tissue morphology, as well as the total mineral content of the bone and the mobilizable anorganic content. ANOVA was used to analyze the measurement data. As a result of the treatment protocol, histological examinations of bone morphology showed osteoid degeneration, as well as an altered state of the bone matrix. These findings are supported by the DEXA images, which showed a time-dependent decrease in surface mineral content, in parallel, an increase in the mobilizable anorganic content of the bone was detected. These results suggest that chlorobenzene administered may be a causal factor and changes in bone tissue structure can be traced.

Artificial breeding is a valid strategy for the reverse of current extinction tendency in wild population of amphibian like toads. Considering public health, an alternative to antibiotics is demanded for ameliorating survival of toads during the culture period. Relying on the cognition of probiotics or antagonistic bacteria, the present work investigated viability and soil microorganism variations induced by distribution characteristic on toads using high-throughput sequencing technology. Comparison and analysis of soil metagenome from clustered and depopulated groups distinguished by toad behavior showed differences of bacterial community composition (e.g., Proteobacteria bacterium TMED72 and Nannocystis exedens) and antibiotic resistance genes involving antibiotic efflux and inactivation (e.g., mdtB and acrF). There were 18 and 10 distribution-typical genes independently enriched in Proteobacteria bacterium TMED72 and bacterium TMED88 of clustered group and Nannocystis exedens of depopulated group. In Nannocystis exedens, one of the distribution-typical genes was annotated as 6-phosphogluconate dehydrogenase acting role on bacterial growth restriction. It implied that, compared with the group emerging rare traces, the reduction of soil bacteria which possess genes retarding bacterial growth putatively impairs competitiveness to pathogenic bacteria and results in poor survivability of toads under clustering behavior. With the co-occurrence of virulence genes, more evidences are needed on the antagonistic bacteria Nannocystis exedens as antibiotic substitute.

Gene flow may be limited between urban and non-urban populations of wild animals that can influence their landscape-level genetic structure and potential to adapt to new ecological conditions. To test this idea, we genetically characterized great tit (Parus major) populations breeding in an urban and a forest area 3.5 km apart, differing in several phenotypic traits some of which may contribute to adaptation to urban living. We used 16 microsatellite markers to genotype 189 breeding adult individuals (119 urban and 70 forest birds) and (1) tested whether the two populations are genetically differentiated, and (2) estimated the rate and direction of migration between the sites. Heterozygosity tended to be lower in the urban than in the forest habitat. Genetic population structure analyses did not show a consistent clustering of breeding birds between the urban and forest sites, and this conclusion was not affected by the inclusion of phenotypic data in the analyses. The pairwise fixation index (F_st) was low (0.009) and only 1% of the total genetic variance was explained by variation between populations. Finally, there was detectable gene flow between the two areas, and its estimated values did not suggest asymmetry in the direction of migration. We conclude that great tits living in the city are genetically connected to the nearby forest population by reciprocal migration, which may explain the low level of genetic differentiation.

Given the growing importance of assessing the condition of wild bees in agroecosystems, we focused on developing a BEE indicator that could be easily used by non-expert taxonomists to score bee diversity. Our goal was to create a tool suitable for farm-level use, one that does not require taxonomic expertise nor heavy field work. Since existing literature has emphasized the significance of environmental features surrounding any investigated site, we incorporated this aspect into our design. We began by identifying a user-friendly field tool to differentiate among bee morphogenera, then proceeded by developing a process for data analyses and interpretation. A protocol is also shared. Further on, we run a case-study testing this tool at 13 sites in three countries, differentiating farms based on farming practices (conventional or organic, as proxy of opposite conditions). The results confirmed that (a) a diagnostic table based on morphological similarities is a practical field tool that, in almost all cases, allows for accurate classification of a bee individual into a specific group (morphogenus); (b) the process of analysis, based on number of morphogenera and landscape composition reflects variability among bees and across sites; (c) evaluating environmental features is essential for placing the results of bee variability into the appropriate context.

Biofilms by E. coli is not only the primary cause of recurrent urinary tract infections, but also lead to medical device-associated infections. Ever increasing antibiotic resistance due to biofilms has sparked a search for plant-based replacements. This study examines anti-biofilm potential of essential oils from lemon (Citrus limon), lemongrass (Cymbopogon citratus), and lavender (Lavandula officinalis) against 26 clinical isolates of E. coli. Essential oils (EOs) were extracted by using hydro-distillation and characterized by GC-MS and FT-IR. Biofilms were quantitatively and qualitatively evaluated. The extracted essential oils had yields ranging from 1.37 to 1.45 (w/v). The main constituents were limonene (94%) in lemon, citral (42%) and ketones (9%) in lemongrass, and linalool (35%) and linalyl anthranilate (20%) in lavender EO. MICs and MBCs of EOs were in the range of 3.13-50 µg/ml. The oils under investigation exhibited notable biofilm inhibition and eradication properties. The percent inhibition and eradication varied between 6-89% and 3-82.25% (p < 0.0001), respectively. These findings suggest that essential oils from lemon, lemongrass, and lavender may offer a promising natural approach to combat E. coli biofilms and associated infections. Further research is warranted to elucidate the underlying mechanisms of action and to explore their clinical applications.

Invasive plants can disrupt the growth performance of native plants by releasing allelochemicals affecting on litter decomposition. Furthermore, these invaders can establish a plant-soil feedback loop with soil microorganisms, which promotes their continued successful invasion primarily through decomposition process. Consequently, it is of the utmost importance to conduct research that analyzes the impacts of invasive plants' allelopathy on their interaction with soil microorganisms. This study aims to investigate the effects of Amaranthus retroflexus L., an invasive Amaranthaceae plant's allelopathy, on its interaction with soil bacterial communities, compared to the native plant A. tricolor L., and also the impacts of the allelopathy of Amaranthus retroflexus on soil enzyme activities. The research was conducted via an indoor planting experiment in which a gradient of Amaranthus retroflexus leaf litter was added. In particular, Amaranthus retroflexus leaf litter resulted in an increase in pH, electrical conductivity, total nitrogen, and neutral protease activity in soil under certain treatments. The amount of Amaranthus retroflexus leaf litter and the form of incubation condition may be the primary determinants of the composition of bacterial communities in soil and the number of functional gene pathways of soil bacteria involved in the decomposition process (especially the decomposition of carbon-containing substances), rather than the alpha diversity of soil bacteria. Consequently, Amaranthus retroflexus may predominantly modify the composition of bacterial communities in soil and the number of functional gene pathways of soil bacteria involved in the decomposition process, rather than the alpha diversity of soil bacteria, to facilitate its subsequent invasion.

The term 'weasel word' is used for vague, ambiguous, or misleading language when the speaker creates an impression of meaning or certainty without committing to specific facts. In academic writings, clear presentation of the declarant's thoughts is inevitable for the transmission and/or sharing of knowledge with high fidelity; hence, weasel words and phrases should be avoided. So far, the topic has received little attention in the behavioural sciences, including ethology, although research in fields focusing on behaviour and the mind provide fertile ground where such rhetorical strategies may go unnoticed. By presenting examples of weasel words used in ethology, we aim to demonstrate how they can lead to misunderstandings among scientists, as well as to prolonged and unproductive debates. We argue that the use of weasel words may stem equally from ingrained bad habits, knowledge gaps, anthropomorphism and inconsistent jargon. Instead of referring to mental states, the description of the behaviours should be in focus from a functional point of view. This allows more precise behaviour measurement and greater agreement in the use of terminology. Adopting a more descriptive and precise terminology may facilitate interdisciplinary discussions and lay the groundwork for novel approaches, such as synthetic or computational ethology.