Next-generation methods for early disease detection in crops.

Plant pathogens are commonly identified in the field by the typical disease symptoms that they can cause. The efficient early detection and identification of pathogens are essential procedures to adopt effective management practices that reduce or prevent their spread in order to mitigate the negative impacts of the disease. In this review, the traditional and innovative methods for early detection of the plant pathogens highlighting their major advantages and limitations are presented and discussed. Traditional techniques of diagnosis used for plant pathogen identification are focused typically on the DNA, RNA (when molecular methods), and proteins or peptides (when serological methods) of the pathogens. Serological methods based on mainly enzyme-linked immunosorbent assay (ELISA) are the most common method used for pathogen detection due to their high-throughput potential and low cost. This technique is not particularly reliable and sufficiently sensitive for many pathogens detection during the asymptomatic stage of infection. For non-cultivable pathogens in the laboratory, nucleic acid-based technology is the best choice for consistent pathogen detection or identification. Lateral flow systems are innovative tools that allow fast and accurate results even in field conditions, but they have sensitivity issues to be overcome. PCR assays performed on last-generation portable thermocyclers may provide rapid detection results in situ. The advent of portable instruments can speed pathogen detection, reduce commercial costs, and potentially revolutionize plant pathology. This review provides information on current methodologies and procedures for the effective detection of different plant pathogens. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Identifying conserved genes involved in crop tolerance to cold stress.

Low temperature is a limiting factor for crop productivity in tropical and subtropical climates. Cold stress response in plants involves perceiving and relaying the signal through a transcriptional cascade composed of different transduction components, resulting in altered gene activity. We performed a meta-analysis of four previously published datasets of cold-tolerant and cold-sensitive crops to better understand the gene regulatory networks and identify key genes involved in cold stress tolerance conserved across phylogenetically distant species. Re-analysing the raw data with the same bioinformatics pipeline, we identified common cold tolerance-related genes. We found 236 and 242 commonly regulated genes in sensitive and tolerant genotypes, respectively. Gene enrichment analysis showed that protein modifications, hormone metabolism, cell wall, and secondary metabolism are the most conserved pathways involved in cold tolerance. Upregulation of the abiotic stress (heat and drought/salt) related genes [heat shock N -terminal domain-containing protein, 15.7kDa class I-related small heat shock protein-like, DNAJ heat shock N -terminal domain-containing protein, and HYP1 (HYPOTHETICAL PROTEIN 1)] in sensitive genotypes and downregulation of the abiotic stress (heat and drought/salt) related genes (zinc ion binding and pollen Ole e 1 allergen and extensin family protein) in tolerant genotypes was observed across the species. Almost all development-related genes were upregulated in tolerant and downregulated in sensitive genotypes. Moreover, protein-protein network analysis identified highly interacting proteins linked to cold tolerance. Mapping of abiotic stress-related genes on analysed species genomes provided information that could be essential to developing molecular markers for breeding and building up genetic improvement strategies using CRISPR/Cas9 technologies.

Meta-analysis of transcriptomic responses to cold stress in plants.

Transcriptomic analyses are needful tools to gain insight into the molecular mechanisms underlying plant responses to abiotic stresses. The aim of this study was to identify key genes differentially regulated in response to chilling stress in various plant species with different levels of tolerance to low temperatures. A meta-analysis was performed using the RNA-Seq data of published studies whose experimental conditions were comparable. The results confirmed the importance of ethylene in the hormonal cross-talk modulating the defensive responses against chilling stress, especially in sensitive species. The transcriptomic activity of five Ethylene Response Factors genes and a REDOX Responsive Transcription Factor 1 involved in hormone-related pathways belonging to ethylene metabolism and signal transduction were induced. Transcription activity of two genes encoding for heat shock factors was enhanced, together with various genes associated with developmental processes. Several transcription factor families showed to be commonly induced between different plant species. Protein-protein interaction networks highlighted the role of the photosystems I and II, as well as genes encoding for HSF and WRKY transcription factors. A model of gene regulatory network underlying plant responses to chilling stress was developed, allowing the delivery of new candidate genes for genetic improvement of crops towards low temperatures tolerance.

An Epigenetic Alphabet of Crop Adaptation to Climate Change.

Crop adaptation to climate change is in a part attributed to epigenetic mechanisms which are related to response to abiotic and biotic stresses. Although recent studies increased our knowledge on the nature of these mechanisms, epigenetics remains under-investigated and still poorly understood in many, especially non-model, plants, Epigenetic modifications are traditionally divided into two main groups, DNA methylation and histone modifications that lead to chromatin remodeling and the regulation of genome functioning. In this review, we outline the most recent and interesting findings on crop epigenetic responses to the environmental cues that are most relevant to climate change. In addition, we discuss a speculative point of view, in which we try to decipher the "epigenetic alphabet" that underlies crop adaptation mechanisms to climate change. The understanding of these mechanisms will pave the way to new strategies to design and implement the next generation of cultivars with a broad range of tolerance/resistance to stresses as well as balanced agronomic traits, with a limited loss of (epi)genetic variability.

Thymol protects against 6-hydroxydopamine-induced neurotoxicity in in vivo and in vitro model of Parkinson's disease via inhibiting oxidative stress.

BACKGROUND: Parkinson's disease (PD) is a multifactorial movement disorder with the progressive degeneration of the nigrostriatal system that impairs patients' movement ability. Oxidative stress has been found to affect the etiology and pathogenesis of PD. Thymol, a monoterpenic phenol, is one of the most important dietary constituents in thyme species. It has been used in traditional medicine and possesses some properties including antioxidant, free radical scavenging, anti-inflammatory. In this study, in vitro and in vivo experiments were performed with the thymol in order to investigate its potential neuroprotective effects in models of PD. METHODS: The present study aimed to evaluate the therapeutic potential of thymol in 6-hydroxydopamine (6-OHDA)-induced cellular and animal models of PD.  RESULTS: Post-treatment with thymol in vitro was found to protect PC12 cells from toxicity induced by 6-OHDA administration in a dose-dependent manner by (1) increasing cell viability and (2) reduction in intracellular reactive oxygen species, intracellular lipid peroxidation, and annexin-positive cells. In vivo, post-treatment with thymol was protective against neurodegenerative phenotypes associated with systemic administration of 6-OHDA. Results indicated that thymol improved the locomotor activity, catalepsy, akinesia, bradykinesia, and motor coordination and reduced the apomorphine-caused rotation in 6-OHDA-stimulated rats. Increased level of reduced glutathione content and a decreased level of MDA (malondialdehyde) in striatum were observed in the 6-OHDA rats post-treated with thymol. CONCLUSIONS: Collectively, our findings suggest that thymol exerts protective effects, possibly related to an anti-oxidation mechanism, in these in vitro and in vivo models of Parkinson's disease.

Botanical, Phytochemical, Anti-Microbial and Pharmaceutical Characteristics of Hawthorn (Crataegusmonogyna Jacq.), Rosaceae.

Hawthorn (Crataegus monogyna Jacq.) is a wild edible fruit tree of the genus Crataegus, one of the most interesting genera of the Rosaceae family. This review is the first to consider, all together, the pharmaceutical, phytochemical, functional and therapeutic properties of C. monogyna based on numerous valuable secondary metabolites, including flavonoids, vitamin C, glycoside, anthocyanin, saponin, tannin and antioxidants. Previous reviews dealt with the properties of all species of the entire genera. We highlight the multi-therapeutic role that C. monogyna extracts could have in the treatment of different chronic and degenerative diseases, mainly focusing on flavonoids. In the first part of this comprehensive review, we describe the main botanical characteristics and summarize the studies which have been performed on the morphological and genetic characterization of the C. monogyna germplasm. In the second part, the key metabolites and their nutritional and pharmaceutical properties are described. This work could be an essential resource for promoting future therapeutic formulations based on this natural and potent bioactive plant extract.