Occurrence and diversity of Xanthomonas campestris pv. campestris in vegetable brassica fields in Nepal

Black rot caused by Xanthomonas campestris pv. campestris was found in 28 sampled cabbage fields in five major cabbage-growing districts in Nepal in 2001 and in four cauliflower fields in two districts and a leaf mustard seed bed in 2003. Pathogenic X. campestris pv. campestris strains were obtained from 39 cabbage plants, 4 cauliflower plants, and 1 leaf mustard plant with typical lesions. Repetitive DNA polymerase chain reaction-based fingerprinting (rep-PCR) using repetitive extragenic palindromic, enterobacterial repetitive intergenic consensus, and BOX primers was used to assess the genetic diversity. Strains were also race typed using a differential series of Brassica spp. Cabbage strains belonged to five races (races 1, 4, 5, 6, and 7), with races 4, 1, and 6 the most common. All cauliflower strains were race 4 and the leaf mustard strain was race 6. A dendrogram derived from the combined rep-PCR profiles showed that the Nepalese X. campestris pv. campestris strains clustered separately from other Xanthomonas spp. and pathovars. Race 1 strains clustered together and strains of races 4, 5, and 6 were each split into at least two clusters. The presence of different races and the genetic variability of the pathogen should be considered when resistant cultivars are bred and introduced into regions in Nepal to control black rot of brassicas

Vitex agnus-castus L.: main features and nutraceutical perspectives

Medicinal plants are used worldwide due to their lower risk of side effects and eco-friendly, cost-effective production when compared to chemical drugs, encouraging researchers to further exploit the therapeutic potential of the former. One of the most popular medicinal plants is Vitex agnus-castus L., grown in tropical and sub-tropical regions, to which different health benefits have already been attributed. In this perspective article, the in vitro and in vivo therapeutic properties of V. agnus-castus L. have been analyzed and reviewed with a special focus on its health-promoting effects and potential nutraceutical applications.The authors acknowledge the support of the research project: Nutraceutica come supporto nutrizionale nel paziente oncologico, CUP: B83D18000140007. E.B.S. acknowledges the sponsorship of the projects M-ERA-NET-0004/2015-PAIRED and UIDB/04469/2020 (strategic fund); A.M.S. acknowledges UIDB/04033/2020 (CITAB), receiving support from the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and co-financed by FEDER under the Partnership Agreement PT2020.info:eu-repo/semantics/publishedVersio

Sage species case study on a spontaneous mediterranean plant to control phytopathogenic fungi and bacteria

Sage species belong to the family of Labiatae/Lamiaceae and are diffused worldwide. More than 900 species of sage have been identified, and many of them are used for different purposes, i.e., culinary uses, traditional medicines and natural remedies and cosmetic applications. Another use of sage is the application of non-distilled sage extracts and essential oils to control phytopathogenic bacteria and fungi, for a sustainable, environmentally friendly agriculture. Biocidal propriety of non-distilled extracts and essential oils of sage are w documented. Antimicrobial effects of these sage extracts/essential oils depend on both sage species and bacteria and fungi species to control. In general, it is possible to choose some specific extracts/essential oils to control specific phytopathogenic bacteria or fungi. In this context, the use of nanotechnology techniques applied to essential oil from salvia could represent a future direction for improving the performance of eco-compatible and sustainable plant defence and represents a great challenge for the future.The authors acknowledge the support of the research project: Nutraceutica come supporto nutrizionale nel paziente oncologico, CUP: B83D18000140007. E.B.S. acknowledges the sponsorship of the projects M-ERA-NET-0004/2015-PAIRED and UIDB/04469/2020 (strategic fund), receiving support from the Portuguese Science and Technology Foundation, Ministry of Science and Education (FCT/MEC) through national funds, and co-financed by FEDER, under the Partnership Agreement PT2020. The authors also acknowledge Agricultural Department of Campania Region (Italy) for financial support.info:eu-repo/semantics/publishedVersio

Astragalus (Astragalus membranaceus Bunge): botanical, geographical, and historical aspects to pharmaceutical components and beneficial role

Medicinal plants always are part of folk medicine and are nowadays receiving worldwide attention for prophylaxis, management, and treatment of several diseases, as an alternative to chemical drugs. The current work provided a comprehensive overview and analysis of the Astragalus and health relationship in literature. The analysis of their therapeutic potential is thus instrumental to understand their bioactivity. Among these, the flowering medicinal plant Astragalus membranaceus has raised interest due to several beneficial health effects. This perspective review discussed the botanical, geographical, historical, and the therapeutic properties of A. membranaceus, with a special focus on its health improving effects and medicinal applications both in vitro and in vivo.Funding provided by Università degli Studi di Napoli Federico II within the CRUI-CARE Agreementinfo:eu-repo/semantics/publishedVersio

The plant pathogen Pseudomonas syringae pv. tomato is genetically monomorphic and under strong selection to evade tomato immunity

addresses: Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, Virginia, United States of America.notes: PMCID: PMC3161960types: Journal Article; Research Support, U.S. Gov't, Non-P.H.S.This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.Recently, genome sequencing of many isolates of genetically monomorphic bacterial human pathogens has given new insights into pathogen microevolution and phylogeography. Here, we report a genome-based micro-evolutionary study of a bacterial plant pathogen, Pseudomonas syringae pv. tomato. Only 267 mutations were identified between five sequenced isolates in 3,543,009 nt of analyzed genome sequence, which suggests a recent evolutionary origin of this pathogen. Further analysis with genome-derived markers of 89 world-wide isolates showed that several genotypes exist in North America and in Europe indicating frequent pathogen movement between these world regions. Genome-derived markers and molecular analyses of key pathogen loci important for virulence and motility both suggest ongoing adaptation to the tomato host. A mutational hotspot was found in the type III-secreted effector gene hopM1. These mutations abolish the cell death triggering activity of the full-length protein indicating strong selection for loss of function of this effector, which was previously considered a virulence factor. Two non-synonymous mutations in the flagellin-encoding gene fliC allowed identifying a new microbe associated molecular pattern (MAMP) in a region distinct from the known MAMP flg22. Interestingly, the ancestral allele of this MAMP induces a stronger tomato immune response than the derived alleles. The ancestral allele has largely disappeared from today's Pto populations suggesting that flagellin-triggered immunity limits pathogen fitness even in highly virulent pathogens. An additional non-synonymous mutation was identified in flg22 in South American isolates. Therefore, MAMPs are more variable than expected differing even between otherwise almost identical isolates of the same pathogen strain

The Plant Pathogen Pseudomonas syringae pv. tomato Is Genetically Monomorphic and under Strong Selection to Evade Tomato Immunity

Recently, genome sequencing of many isolates of genetically monomorphic bacterial human pathogens has given new insights into pathogen microevolution and phylogeography. Here, we report a genome-based micro-evolutionary study of a bacterial plant pathogen, Pseudomonas syringae pv. tomato. Only 267 mutations were identified between five sequenced isolates in 3,543,009 nt of analyzed genome sequence, which suggests a recent evolutionary origin of this pathogen. Further analysis with genome-derived markers of 89 world-wide isolates showed that several genotypes exist in North America and in Europe indicating frequent pathogen movement between these world regions. Genome-derived markers and molecular analyses of key pathogen loci important for virulence and motility both suggest ongoing adaptation to the tomato host. A mutational hotspot was found in the type III-secreted effector gene hopM1. These mutations abolish the cell death triggering activity of the full-length protein indicating strong selection for loss of function of this effector, which was previously considered a virulence factor. Two non-synonymous mutations in the flagellin-encoding gene fliC allowed identifying a new microbe associated molecular pattern (MAMP) in a region distinct from the known MAMP flg22. Interestingly, the ancestral allele of this MAMP induces a stronger tomato immune response than the derived alleles. The ancestral allele has largely disappeared from today's Pto populations suggesting that flagellin-triggered immunity limits pathogen fitness even in highly virulent pathogens. An additional non-synonymous mutation was identified in flg22 in South American isolates. Therefore, MAMPs are more variable than expected differing even between otherwise almost identical isolates of the same pathogen strain