Search Results (1,187)

Fusarium diseases are among the most dangerous fungal diseases of plants. To date, there are no plant protectants that completely prevent fusariosis. Current breeding trends are therefore focused on increasing genetic resistance. While global modern maize breeding relies on various molecular genetics techniques, they are useless without a precise characterization of genomic regions that determine plant physiological responses to fungi. The aim of this study was thus to characterize the expression of candidate genes that were previously reported by our team as harboring markers linked to fusarium resistance in maize. The plant material included one susceptible and four resistant varieties. Biotic stress was induced in adult plants by inoculation with fungal spores under controlled conditions. qRT-PCR was performed. The analysis focused on four genes that encode for GDSL esterase/lipase (LOC100273960), putrescine hydroxycinnamyltransferase (LOC103649226), peroxidase 72 (LOC100282124), and uncharacterized protein (LOC100501166). Their expression showed differences between analyzed time points and varieties, peaking at 6 hpi. The resistant varieties consistently showed higher levels of expression compared to the susceptible variety, indicating their stronger defense responses. Moreover, to better understand the function of these genes, their expression in various organs and tissues was also evaluated using publicly available transcriptomic data. Our results are consistent with literature reports that clearly indicate the involvement of these genes in the resistance response to fusarium. Thus, they further emphasize the high usefulness of the previously selected markers in breeding programs to select fusarium-resistant maize genotypes. Full article

Honey bees are essential pollinators for the ecosystem and food crops. However, their health and survival face threats from both biotic and abiotic stresses. Fungi, microsporidia, and bacteria might significantly contribute to colony losses. Therefore, rapid and sensitive diagnostic tools are crucial for effective disease management. In this study, molecular assays were developed to quickly and efficiently detect the main honey bee pathogens: Nosema ceranae, Aspergillus flavus, Paenibacillus larvae, and Black queen cell virus. In this context, new primer pairs were designed for use in quantitative Real-time PCR (qPCR) reactions. Various protocols for extracting total nucleic acids from bee tissues were tested, indicating a CTAB-based protocol as the most efficient and cost-effective. Furthermore, excluding the head of the bee from the extraction, better results were obtained in terms of quantity and purity of extracted nucleic acids. These assays showed high specificity and sensitivity, detecting up to 250 fg of N. ceranae, 25 fg of P. larvae, and 2.5 pg of A. flavus DNA, and 5 pg of BQCV cDNA, without interference from bee DNA. These qPCR assays allowed pathogen detection within 3 h and at early stages of infection, supporting timely and efficient management interventions. Full article

Root-knot nematode (Meloidogyne incognita) is a globally destructive plant-parasitic nematode that severely impedes the sustainable production of horticultural crops. Metabolic reprogramming in plant roots represents the host response to M. incognita infection that can also be exploited by the nematode to facilitate its parasitism. In this study, untargeted metabolomics was employed to analyze metabolic changes in cucumber roots following nematode inoculation, with the goal of identifying differentially accumulated metabolites that may influence M. incognita behavior. Metabolomic analysis revealed that M. incognita significantly altered the cucumber root metabolome, triggering an accumulation of lipids and organic acids and enriching biotic stress-related pathways such as alkaloid biosynthesis and linoleic acid metabolism. Among differentially accumulated metabolites, myristic acid and hexadecanal were selected for further study due to their potential roles in nematode inhibition. In vitro assays demonstrated that both metabolites suppressed egg hatching and reduced infectivity of M. incognita, while pot experiments indicated a correlation between their application and reduced root gall formation. Chemotaxis assays further revealed that both metabolites exerted repellent effects on the chemotactic migration of M. incognita J2 and suppressed the transcriptional expression of two motility-and feeding-related neuropeptides, Mi-flp-1 and Mi-flp-18. In conclusion, this study demonstrates the significant potential of differentially accumulated metabolites induced by M. incognita infection for nematode disease control, achieved by interfering with nematode chemotaxis and subsequent infection. This work also provides deeper insights into the metabolomic mechanisms underlying the cucumber-M. incognita interaction. Full article

Soil salinization is a major environmental constraint that poses a significant threat to global agricultural productivity and food security. Coix lacryma-jobi L., a minor cereal crop that is valued for its nutritional and medicinal properties, displays moderate susceptibility to salinity stress. Although exogenous treatments have been demonstrated to enhance plant resilience against various biotic and abiotic stresses, the potential of nano-silicon (NaSi), melatonin (MT), and their combined application in mitigating salinity-induced damage, particularly in relation to the medicinal properties of this medicinal and edible crop, remains poorly understood. This study investigated the effects of exogenous NaSi and MT application on Coix under salinity stress using two varieties with contrasting salinity tolerances. The plants were subjected to salinity stress and treated with NaSi, MT, or a combination of both. The results revealed that salinity stress significantly impaired the agronomic traits, physiological performance, and accumulation of medicinal compounds of Coix. Exogenous MT application effectively alleviated salinity-induced damage to agronomic and physiological parameters, exhibiting superior protective effects compared to NaSi treatment. Strikingly, the combined application of MT and NaSi demonstrated synergistic effects, leading to substantial improvements in growth and physiological indices. However, the medicinal components were only marginally affected by exogenous treatments under both control and salinity-stressed conditions. Further clarification of the molecular mechanisms underlying salinity stress responses and exogenous substance-induced effects is critical to achieving a comprehensive understanding of these protective mechanisms. Full article

The Water Framework Directive (WFD) was designed to protect the quality of all water resources. For reservoirs, the ecological potential classification assesses biological parameters, evaluating only the phytoplankton community. Thus, this study aimed to evaluate the effectiveness of using fish communities to determine water quality in reservoirs. A literature review was conducted to gather information on how fish community data were integrated into reservoir water quality assessment under the WFD. This work includes an exploratory case study of the Aguieira Reservoir (Portugal), evaluating the ichthyofauna community, along with physical, chemical, and biological assessment of the water. The results of the review show that fish abundance and composition (sensitive metrics) should be used to develop ecological indices for assessing water quality in reservoirs. However, the effects of anthropogenic pressures and invasive species are not included in the calculation of most proposed indices. The case study serves as an illustrative example and demonstrates low abundance and composition of the fish community with a high percentage of invasive species, revealing a poor water quality, regarding ichthyofauna biotic index results (F-IBIP). Nevertheless, including these metrics in the classification of ecological potential can help guide restoration strategies to mitigate the effects of anthropogenic pressures. Full article

The ongoing genetic erosion of natural Prunus armeniaca populations in their native habitats underscores the urgent need for targeted conservation and restoration strategies. This study provides the first comprehensive characterization of P. armeniaca populations in the Almaty region of Kazakhstan, integrating morphological descriptors (46 parameters), molecular markers, geobotanical, and remote sensing analyses. Geobotanical and remote sensing analyses enhanced understanding of accession distribution, geological features, and ecosystem health across sites, while also revealing their vulnerability to various biotic and abiotic threats. Of 111 morphologically classified accessions, 54 were analyzed with 13 simple sequence repeat (SSR) markers and four DNA barcoding regions. Our findings demonstrate the necessity of integrated morphological and molecular analyses to differentiate closely related accessions. Genetic analysis identified 11 distinct populations with high heterozygosity and substantial genetic variability. Eight populations exhibited 100% polymorphism, indicating their potential as sources of adaptive genetic diversity. Cluster analysis grouped populations into three geographic clusters, suggesting limited gene flow across Gorges (features of a mountainous landscape) and greater connectivity within them. These findings underscore the need for site-specific conservation strategies, especially for genetically distinct, isolated populations with unique allelic profiles. This study provides a valuable foundation for prioritizing conservation targets, confirming genetic redundancies, and preserving genetic uniqueness to enhance the efficiency and effectiveness of the future conservation and use of P. armeniaca genetic resources in the region. Full article

Magenta Cherry or Eugenia (Syzygium paniculatum Gaertn) is an underutilized berry species with an interesting source of functional components. This study aimed to evaluate these berries’ morphometric, nutritional, and phytochemical characteristics at two ripening stages, CM: consumer maturity (CM) and OM: over-maturity. Morphometric analysis revealed size and weight parameters comparable to commercial berries such as blueberries. Fresh fruits were processed into pulverized material, and in this, a proximate analysis was evaluated, showing high moisture content (88.9%), dietary fiber (3.56%), and protein (0.63%), with negligible fat, indicating suitability for low-calorie diets. Phytochemical screening by HPLC identified gallic acid, chlorogenic acid, hydroxycinnamic acid, ferulic acid, quercetin, rutin, and condensed tannins. Ethanol extracts showed stronger bioactive profiles than aqueous extracts, with significant antioxidant capacity (up to 803.40 µmol _Trolox/g via Ferric Reducing Antioxidant Power (FRAP assay). Fourier-transform infrared spectroscopy (FTIR) and Raman spectroscopic analyses established structural transformations of hydroxyl, carbonyl, and aromatic groups associated with ripening. These changes were supported by observed variations in anthocyanin and flavonoid contents, both higher at the CM stage. A notable pigment loss in OM fruits could be attributed to pH changes, oxidative degradation, enzymatic activity loss, and biotic stressors. Antioxidant assays (DPPH, ABTS, and FRAP) confirmed higher radical scavenging activity in CM-stage berries. Elemental analysis identified minerals such as potassium, calcium, magnesium, iron, and zinc, although in moderate concentrations. In summary, Syzygium paniculatum Gaertn fruit demonstrates considerable potential as a source of natural antioxidants and bioactive compounds. These findings advocate for greater exploration and sustainable use of this native berry species in functional food systems. Full article

Root-emitted volatile organic compounds (VOCs) play a critical role in below-ground ecological interactions by mediating communication between plants, pests, and their natural enemies. This study investigates the chemotactic behavior of three slug-parasitic nematode species—Phasmarhabditis papillosa, Oscheius myriophilus, and Oscheius onirici—in response to four carrot (Daucus carota) root-derived VOCs: α-pinene, terpinolene, bornyl acetate, and 2-ethyl-1-hexanol. Using a modified Petri dish assay, infective juveniles (IJs) were exposed to each compound across four concentrations (pure, 1000 ppm, 10 ppm, and 0.03 ppm), and their directional movement was quantified using a chemotaxis index (CI). The results revealed strong species-specific and concentration-dependent patterns. O. myriophilus exhibited the highest motility and repellency, particularly toward bornyl acetate and terpinolene, indicating its potential for use in VOC-guided biocontrol strategies. O. onirici showed moderate but consistent attraction to most VOCs, while P. papillosa exhibited generally weak or repellent responses, especially at higher concentrations. None of the compounds tested functioned as strong attractants (CI ≥ 0.2), suggesting that plant-derived VOCs alone may not be sufficient to direct nematode recruitment under field conditions. However, their integration with other biotic cues could enhance nematode-based “lure-and-infect” systems for sustainable slug control in carrot cropping systems. Full article

Aquatic plants, as sedentary lifestyle organisms that accumulate chemical substances from their surroundings, can serve as valuable indicators of long-term anthropogenic pressure. In Poland, water monitoring is limited both spatially and temporally, which hampers a comprehensive assessment of water quality. Since the implementation of the Water Framework Directive (WFD), biotic elements, including macrophytes, have played an increasingly important role in water monitoring. Moreover, running waters, due to their dynamic nature, are susceptible to episodic pollution inputs that may be difficult to detect during isolated, point-in-time sampling campaigns. The analysis of stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotope signatures in macrophytes enables the identification of elemental sources, including potential pollutants. Research conducted between 2008 and 2011 encompassed 38 sites along 15 rivers and 108 sites across 21 lakes in northern Poland. This study focused on the isotope signatures of three pondweed species: Stuckenia pectinata, Potamogeton perfoliatus, and Potamogeton crispus. The results revealed statistically significant differences in the δ¹³C and δ¹⁵N values of plant organic matter between river and lake environments. Higher δ¹⁵N values were observed in rivers, whereas higher δ¹³C values were recorded in lakes. Spearman correlation analysis showed a negative relationship between δ¹³C and δ¹⁵N, as well as correlations between δ¹⁵N and the concentrations of Ca²⁺ and HCO₃⁻. A positive correlation was also found between δ¹³C and dissolved oxygen levels. These findings confirm the utility of δ¹³C and, in particular, δ¹⁵N as indicators of anthropogenic eutrophication, including potentially domestic sewage input and its impact on aquatic ecosystems. Full article

Protecting the soil ecosystem’s functioning is one of the main goals of recent regulations of chemicals. It is important to take soil biodiversity into account when designing cropping systems and measuring their impacts. Our main objective was to evaluate the effects of an organic amendment on soil nematode biodiversity compared to two years of fumigation. The plot-trial was conducted on tomato and lettuce plants under greenhouse, and free-living nematodes were used as bio-indicators of soil health. Treatments included a soil fumigant (applied once or twice over time), water control, and an organic substance. Soil samplings were carried out to determine the Meloidogyne incognita reproduction factor and the soil nematode community analysis using soil biological indicators. Data showed that soil fumigation clearly made the soil increasingly dependent on chemicals. Furthermore, fumigants suppressed pests and pathogens as well as their natural antagonists, causing a lack of biodiversity. While soils treated with organic matter respond slowly to stressors, they are progressively more suppressive thanks to biodiversity enrichment. Nematodes have proven to be useful indicators of the soil biota in response to biotic or abiotic disturbances. Their species richness and functional diversity make them valid bioindicators of soil management impact. Full article

Background: The short strand-related sequence (SRS) gene family is a class of plant-specific transcription factors related to a group of genes known as the short internode (SHI) or SRS/STY gene family, which plays important roles in regulating plant growth and development and stress responses. Although the SRS genes have been studied in many plants, in cucurbit crops, they have thus far only been identified in cucumber. Methods: In the Cucurbitaceae database from melon (Cucumis melo), cucumber (Cucumis sativus), watermelon (Citrullus lanatus), bottle gourd (Lagenaria siceraria), wax gourd (Benincasa hispida), moschata pumpkin (Cucurbita moschata), and pumpkin (Cucurbita maxima), a total of 60 SRS genes were identified in seven Cucurbitaceae crops, which were classified into three subfamilies. Results: The same subfamily showed conserved motifs and gene structures. The differences in the number of SRS genes in different Cucurbitaceae crops implied likely gene loss or duplication events during evolution. Analysis of promoter cis-regulatory elements indicated that these SRS genes may be involved in hormone response, growth and development, and biotic and abiotic stress responses in plants. Most of the CmSRS genes in melons were expressed in the roots, with a few expressed in the leaves and ovaries. In addition, CmSRS expression was induced by biotic (wilt and powdery mildew) and abiotic (drought and salt) stresses. Subcellular localization of CmSRS proteins showed predominant expression in the nucleus. Conclusions: A total of 60 Cucurbitaceae SRS genes are present in the genomes of seven Cucurbitaceae crops. These cucurbit SRS genes seem to have maintained similar characteristics and functions during the evolutionary process. These results lay the foundation for the study of biological functions of SRS genes in Cucurbitaceae crops. Full article

Investigations of endogenous plant circular RNAs (circRNAs) in several plant species have revealed changes in their circular RNA profiles in response to biotic and abiotic stresses. Recently, circRNAs have emerged as critical regulators of gene expression. The destructive impacts on agriculture due to plant viral infections necessitate better discernment of the involvement of plant circRNAs during viral infection. However, few such studies have been conducted hitherto. Sobemoviruses cause great economic impacts on important crops such as rice, turnip, alfalfa, and wheat. Our current study investigates the dynamics of plant circRNA profiles in the host Arabidopsis thaliana (A. thaliana) during infections with the sobemoviruses Turnip rosette virus (TRoV) and Rice yellow mottle virus (RYMV), as well as the small circular satellite RNA of the Lucerne transient streak virus (scLTSV), focusing on circRNA dysregulation in the host plants and its potential implications in triggering plant cellular defense responses. Towards this, two rounds of deep sequencing were conducted on the RNA samples obtained from infected and uninfected plants followed by the analysis of circular RNA profiles using RNA-seq and extensive bioinformatic analyses. We identified 760 circRNAs, predominantly encoded in exonic regions and enriched in the chloroplast chromosome, suggesting them as key sites for circRNA generation during viral stress. Gene ontology (GO) analysis indicated that these circRNAs are mostly associated with plant development and protein binding, potentially influencing the expression of their host genes. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed photosynthesis as the most affected pathway. Interestingly, the non-coding exogenous scLTSV specifically induced several circRNAs, some of which contain open reading frames (ORFs) capable of encoding proteins. Our biochemical assays demonstrated that transgenic expression of scLTSV in A. thaliana enhanced resistance to TRoV, suggesting a novel strategy for improving plant viral resistance. Our results highlight the complexity of circRNA dynamics in plant–virus interactions and offer novel insights into potential circRNA-based strategies for enhancing plant disease resistance by modulating the differential expression of circRNAs. Full article

Odonata constitute an important invertebrate group that is strongly dependent on water conditions and sensitive to habitat disturbances, rendering them reliable indicators of habitat quality of both aquatic and terrestrial habitats. We studied the compositional and diversity patterns of Odonates in total, and separately for the two suborders (Zygoptera, Anisoptera) in relation to geographic and ecological parameters at the riparian zone of four rivers and one canal within the Axios Delta National Park and the Natura 2000 SAC GR1220002 in northern Greece, using the line transect technique. In total, 6252 individuals belonging to 28 species were identified. The compositional and diversity patterns were significantly different between agricultural and natural sites. Odonata assemblages at croplands were comparatively poorer, dominated by a few, widely distributed, taxonomically proximal species, tolerant to environmental changes, as a result of modifications and consequent alterations of abiotic conditions at croplands, which also led to higher local contribution to β-diversity and species turnover. The absence of several percher, endophytic, and threatened species from agricultural sites led to significantly lower diversity, as a result of environmental filtering due to ecophysiological restrictions. Taxonomic and functional diversity, uniqueness, and Dragonfly Biotic Index (DBI) were significantly higher in riparian forests, due to the sensitivity of damselflies to dehydration, and the avoidance of habitat loss and extreme temperatures by dragonflies, which prefer natural shelters near the ecotone. The newly introduced Conservation Value Index (CVI) revealed 21 conservation hotspots of Odonata (14 at canopy cover sites), widely distributed within the borders of NATURA 2000 SAC GR1220002. Full article

South Korea is one of the world’s major centers for marine shellfish aquaculture. Since the industry’s rapid expansion began in the 1980s, concerns have grown regarding its environmental impacts on coastal marine ecosystems. Evaluating the benthic ecological quality status (EcoQs) of shellfish farms using benthic indices provides a scientific foundation for the sustainable management of aquaculture areas. In our study, five benthic indices (AZTI’s marine biotic index, BENTIX, benthic opportunistic polychaeta amphipoda index, benthic pollution index, and multivariate AMBI) and one composite index were selected to assess EcoQs of shellfish farms in Gangjin Bay, South Korea. Our results revealed significant differences in macrobenthic community structure and EcoQs between November and December in Gangjin Bay. Spearman correlation analysis and principal coordinates analysis (PCoA) demonstrated that the multivariate AMBI (M-AMBI) exhibited the best overall performance among indices. However, considering the ecological complexity, variability in farming practices, and site-specific conditions typical of shellfish aquaculture environments, the use of five benthic indices and a composite index is recommended to ensure a more comprehensive and robust evaluation of EcoQs in Korean shellfish farms. Full article

Plant growth-promoting rhizobacteria (PGPR) are beneficial rhizosphere microorganisms for plants. They can promote plant absorption of nutrients, inhibit pathogenic microorganisms, enhance plant tolerance to abiotic and biotic stresses, and improve plant growth. Isolating new beneficial microbes and elucidating their promoting mechanisms can facilitate the development of microbial fertilizers. This study combined transcriptome sequencing and related experiments to analyze the mechanism by which the endophytic fungus ‘BF-F’ promotes the growth of Sesuvium portulacastrum. We inoculated the ‘BF-F’ fungus beside S. portulacastrum seedlings as the experimental group. Meanwhile, S. portulacastrum seedlings not inoculated with ‘BF-F’ were set as the control group. After inoculation for 0 d, 7 d, 14 d, 21 d, and 28 d, the plant height and the number of roots were measured. Furthermore, transcriptome sequencing on the roots and leaves of the S. portulacastrum was conducted. Differentially expressed genes were screened, and KEGG enrichment analysis was performed. Nitrogen metabolism-related genes were selected, and qRT-PCR was conducted on these genes. Furthermore, we analyzed the metabolomics of ‘BF-F’ and its hormone products. The results showed that inoculation of ‘BF-F’ significantly promoted the growth of S. portulacastrum. After ‘BF-F’ inoculation, a large number of genes in S. portulacastrum were differentially expressed. The KEGG pathway enrichment results indicated that the ‘BF-F’ treatment affected multiple metabolic pathways in S. portulacastrum, including hormone signal transduction and nitrogen metabolism. The auxin signaling pathway was enhanced because of a decrease in AUX expression and an increase in ARF expression. Contrary to the auxin signal transduction pathway, the zeatin (ZT) signaling pathway was suppressed after the ‘BF-F’ treatment. ‘BF-F’ increased the expression of genes related to nitrogen metabolism (NRT, AMT, NR, and GAGOT), thereby promoting the nitrogen content in S. portulacastrum. The metabolites of ‘BF-F’ were analyzed, and we found that ‘BF-F’ can synthesize IAA and ZT, which are important for plant growth. Overall, ‘BF-F’ can produce IAA and enhance the nitrogen use efficiency of plants, which could have the potential to be used for developing a microbial fertilizer. Full article