Genomic insights advance the fight against black rot of crucifers

AbstractXanthomonas campestris pv. campestris, the causal agent of black rot of crucifers, was one of the first bacterial plant pathogens ever identified. Over 130 years later, black rot remains a threat to cabbage, cauliflower, and other Brassica crops around the world. Recent genomic and genetic data are informing our understanding of X. campestris taxonomy, dissemination, inoculum sources, and virulence factors. This new knowledge promises to positively impact resistance breeding of Brassica varieties and management of inoculum sources.

Download Full-text

Identification of Black Rot Resistance in a Wild Brassica Species and Its Potential Transferability to Cauliflower

Agronomy ◽

10.3390/agronomy10091400 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1400

Author(s):

Xiao-Guang Sheng ◽

Ferdinando Branca ◽

Zhen-Qing Zhao ◽

Jian-Sheng Wang ◽

Hui-Fang Yu ◽

...

Keyword(s):

Xanthomonas Campestris ◽

Resistance Breeding ◽

Brassica Species ◽

Gene Location ◽

F1 Hybrids ◽

Black Rot ◽

Resistant Parent ◽

F2 Population ◽

Related Wild Species ◽

Wild Accessions

Black rot is a destructive disease that affects B. oleracea crops, causing significant losses to growers throughout the world. The purpose of this study was to screen out new sources resistant to Xanthomonas campestris pv. campestris race 4 (Xcc4) in 26 cauliflower and six related wild species, and to assess the inheritance of resistance. The results indicate that most of the tested accessions were susceptible or had intermediate resistance, except the Boc4601 (a cauliflower stable inbred line) and PI435896, UNICT5168, and UNICT5169 (wild accessions). Among them, UNICT5169 (Brassica montana) and PI435896 (Brassica balearica) showed the strongest resistance to Xcc4, with significantly lower disease index (DI), area of the infected part (AIP) and proportion of the infected part to the total leaf area (PTL) values. UNICT 5169 was selected as an Xcc4-resistant parent because of its relatively good cross seed-setting rate with cauliflower cultivars. F1 hybrids were successfully produced between this wild resistant accession (UNICT 5169) and one susceptible cauliflower breeding line (Boc3202-4), indicating the potential transferability of this resistance to cauliflower. The results of the symptoms severity evaluation of the F2 population indicate that Xcc4 resistance in UNICT5169 is a quantitative trait, which guides future resistance gene location and black rot resistance breeding.

Download Full-text

Construction of a Linkage Map and QTL analysis for Black Rot Resistance in Brassica oleracea L.

International Journal of Natural Sciences ◽

10.3329/ijns.v1i1.8591 ◽

1970 ◽

Vol 1 (1) ◽

pp. 1-6 ◽

Cited By ~ 7

Author(s):

MAU Doullah ◽

GM Mohsin ◽

K Ishikawa ◽

H Hori ◽

K Okazaki

Keyword(s):

Linkage Map ◽

Brassica Oleracea ◽

Phenotypic Variation ◽

Xanthomonas Campestris ◽

Resistance Breeding ◽

Black Rot ◽

Significant Qtls ◽

Disease Rating ◽

Genomic Regions ◽

Xanthomonas Campestris Pv Campestris

For quantitative trait loci (QTL) controlling resistance to Xanthomonas campestris pv. Campestris, we constructed linkage map using cleaved amplified plymorphic sequences (CAPS) and sequence-related amplified polymorphism (SRAP) analysis with disease rating of F3 families obtained from a susceptible broccoli and resistant cabbage [Green commet P09 × Reiho P01]. We established inoculation technique. In this technique, leaves from approximately 50-day old F3 plants were inoculated by cutting 1.0 cm at mid vain near the margins. A total of 38 CAPS and 60 SRAP primer pairs were screened to assess parental polymorphism against black rot resistance. Ninety two markers were distributed in 10 linkage groups (LGs) covering 320.5 cM (centimorgan), with average 3.56 cM interval between markers. Two genomic regions on LG 2 and LG 9 were significantly associated with resistance to the disease. The analysis revealed QTLs in the map interval between CAM1 – GSA1 on LG 2 accounting for up to 10% of the phenotypic variation and one QTL in the map interval between F12-R12e – BORED on LG 9 explaining 16% phenotypic variation with LOD score of 3.09. Two additional non-significant QTLs on LG 3 in the interval between CHI – ASB1 (LOD = 2.04) and on LG 7 in the interval between IPI – FLC3 (LOD = 2.25) were also detected for resistance to the disease. The QTLs, which were mapped to LG 2 and LG 9 for the disease, could be useful for marker-assisted selection in resistance breeding. Key words: Linkage map; QTL; Black rot; Resistance; Brassica oleracea DOI: http://dx.doi.org/10.3329/ijns.v1i1.8591 International Journal of Natural Sciences (2011), 1(1):1-6

Download Full-text

Evaluation of Proposed Amended Names of Several Pseudomonads and Xanthomonads and Recommendations

Phytopathology ◽

10.1094/phyto.2000.90.3.208 ◽

2000 ◽

Vol 90 (3) ◽

pp. 208-213 ◽

Cited By ~ 34

Author(s):

N. W. Schaad ◽

A. K. Vidaver ◽

G. H. Lacy ◽

K. Rudolph ◽

J. B. Jones

Keyword(s):

Pseudomonas Syringae ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Plant Pathogens ◽

Genetic Data ◽

Published Data ◽

Type B ◽

American Phytopathological Society ◽

Code Of Nomenclature ◽

International Code Of Nomenclature

In 1980, over 90% of all plant-pathogenic pseudomonads and xanthomonads were lumped into Pseudomonas syringae and Xanthomonas campestris, respectively, as pathovars. The term “pathovar” was created to preserve the name of plant pathogens, but has no official standing in nomenclature. Proposals to elevate and rename several pathovars of the genera Pseudomonas and Xanthomonas to the rank of species has caused great confusion in the literature. We believe the following changes have merit and expect to adopt them for publication in a future American Phytopathological Society Laboratory Guide for Identification of Plant Pathogenic Bacteria. Upon review of published data and the Rules of The International Code of Nomenclature of Bacteria, we make the following recommendations. We reject the proposal to change the name of P. syringae pvs. phaseolicola and glycinea to P. savastanoi pvs. phaseolicola and glycinea, respectively, because both pathogens are easily differentiated phenotypically from pv. savastanoi and convincing genetic data to support such a change are lacking. We accept the elevation of P. syringae pv. savastanoi to the rank of species. We accept the reinstatement of X. oryzae to the rank of species with the inclusion of X. oryzicola as a pathovar of X. oryzae and we accept the species X. populi. We agree with the elevation of the pvs. cassavae, cucurbitae, hyacinthi, pisi, and translucens to the rank of species but not pvs. melonis, theicola, and vesicatoria type B. We recommend that all type A X. vesicatoria be retained as X. campestris pv. vesicatoria and all type B X. vesicatoria be named X. exitiosa. We reject the newly proposed epithets arboricola, bromi, codiaei (poinsettiicola type B), hortorum, sacchari, and vasicola and the transfer of many pathovars of X. campestris to X. axonopodis. The proposed pathovars of X. axonopodis should be retained as pathovars of X. campestris.

Download Full-text

EXPLORATION OF BACTRIOPHAGE VIRULENT TO XANTHOMONAS CAMPESTRIS PV CAMPETRIS TOWARD DEVELOPMENT AS BIOCONTROL AGENT FOR CABBAGE BLACK ROT DISEASE

Caraka Tani Journal of Sustainable Agriculture ◽

10.20961/carakatani.v27i1.14344 ◽

2017 ◽

Vol 27 (1) ◽

pp. 7

Author(s):

Sri Widadi ◽

Linayanti Darsana ◽

Sumijati Sumijati

Keyword(s):

Xanthomonas Campestris ◽

Biocontrol Agent ◽

Low Cost ◽

Biocontrol Agents ◽

Black Rot ◽

Integrated Disease Management ◽

Central Java ◽

The World ◽

Negative Effect ◽

Rot Disease

Black rot disease which is caused by Xanthomonas campestris pv campetris is animportant disease on cabbage and so far could not be controlled satisfactory yet.Recently, people getting conscious the negative effect of applicating synthetic pesticidesand the importance of using biocontrol agents fo controlling pests because they arerelatively save and environmentally friendly. Bacteriophage is viruse that infectsbacteria. The use of phages for disease control is a fast expanding area of plantprotection with great potential to replace the chemical control and now prevalent.Phages can be used effectively as part of integrated disease management strategies.The relative ease of preparing phage treatments and low cost of production of theseagents make them good candidates for widespread use in developing countries as well.So far, in Indonesia bacteriophage exploration for development as biocontrol agents hasnot been conducted yet. On the other hand, Indonesia is one of view countries having alot of biodiversity resourches in the world. So it can be predicted that it is a lot ofbacteriophages strains naturally, which could be developed for biocontrol agents ofblack rot disease in cabbage. This research was aimed to isolate some bacteriophagevirulent to Xanthomonas campestris pv campetris from field. X. campestris pv campetris has been isolated from diseased cabbage in Blumbang, Tawangmangu.Biological characterization assay of 10 diseased cabbage leaf samples showed that allsample were indicated innfected by X. campestris pv campetris. Whereas plaque assayof 10 samples taken from fields showed indication of plague formation. This researchstill be continued to explore more samples form Tawangmangu, and also from othercabbage field in Central Java.

Download Full-text

Genetic Diversity and Population Structure of the Xanthomonas campestris pv. campestris Strains Affecting Cabbages in China Revealed by MLST and Rep-PCR Based Genotyping

The Plant Pathology Journal ◽

10.5423/ppj.oa.06.2021.0088 ◽

2021 ◽

Vol 37 (5) ◽

pp. 476-488

Author(s):

Guo Chen ◽

Congcong Kong ◽

Limei Yang ◽

Mu Zhuang ◽

Yangyong Zhang ◽

...

Keyword(s):

Genetic Diversity ◽

Population Structure ◽

Xanthomonas Campestris ◽

Resistance Breeding ◽

Black Rot ◽

Yield Losses ◽

Mlst Analysis ◽

Pathogen Diversity ◽

Pathogenicity Tests ◽

Xanthomonas Campestris Pv Campestris

Xanthomonas campestris pv. campestris (Xcc) is the causal agent of black rot for cruciferous vegetables worldwide, especially for the cole crops such as cabbage and cauliflower. Due to the lack of resistant cabbage cultivars, black rot has brought about considerable yield losses in recent years in China. Understanding of the pathogen features is a key step for disease prevention, however, the pathogen diversity, population structure, and virulence are largely unknown. In this study, we studied 50 Xcc strains including 39 Xcc isolates collected from cabbage in 20 regions across China, using multilocus sequence genotyping (MLST), repetitive DNA sequence-based PCR (rep-PCR), and pathogenicity tests. For MLST analysis, a total of 12 allelic profiles (AP) were generated, among which the largest AP was AP1 containing 32 strains. Further cluster analysis of rep-PCR divided all strains into 14 DNA groups, with the largest group DNA I comprising of 34 strains, most of which also belonged to AP1. Inoculation tests showed that the representative Xcc strains collected from diverse regions performed differential virulence against three brassica hosts compared with races 1 and 4. Interestingly, these results indicated that AP1/DNA I was not only the main pathotype in China, but also a novel group that differed from the previously reported type races in both genotype and virulence. To our knowledge, this is the first extensive genetic diversity survey for Xcc strains in China, which provides evidence for cabbage resistance breeding and opens the gate for further cabbage-Xcc interaction studies.

Download Full-text

Isolation and Identification of Xanthomonas Campestris Pv. Campestris Causing Black Rot on Cauliflower From Plains of Kerala

International Journal of Scientific Research ◽

10.15373/22778179/feb2014/2 ◽

2012 ◽

Vol 3 (2) ◽

pp. 4-6

Author(s):

S. Lakshmi Prasanna ◽

◽

Dr. S. Ravi Dr. S. Ravi

Keyword(s):

Xanthomonas Campestris ◽

Black Rot ◽

Isolation And Identification ◽

Xanthomonas Campestris Pv Campestris

Download Full-text

Effect of C6-Volatiles on Bioluminescent Plant Pathogens

HortScience ◽

10.21273/hortsci.33.3.557d ◽

1998 ◽

Vol 33 (3) ◽

pp. 557d-557

Author(s):

Jennifer Warr ◽

Fenny Dane ◽

Bob Ebel

Keyword(s):

Biological Activity ◽

Bacterial Growth ◽

Xanthomonas Campestris ◽

Plant Pathogens ◽

Genetically Engineered ◽

The Other ◽

Computer Assisted ◽

Signal Molecules ◽

Low Concentrations

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.

Download Full-text

Making sense of “superbugs” on YouTube: A storytelling approach

Public Understanding of Science ◽

10.1177/0963662521989251 ◽

2021 ◽

pp. 096366252198925

Author(s):

Monika Djerf-Pierre ◽

Mia Lindgren

Keyword(s):

Social Media ◽

Antimicrobial Resistance ◽

Health Knowledge ◽

Social Media Platform ◽

Making Sense ◽

New Knowledge ◽

The World ◽

Media Platform ◽

Youtube Videos ◽

Health Experts

Antimicrobial resistance is one of the greatest challenges facing the world. With the rapid growth of social media, YouTube has become an influential social media platform providing publics with expert health knowledge. This article explores how antimicrobial resistance is communicated on YouTube. Drawing on qualitative media analyses of the most viewed YouTube videos 2016–2020, we identify seven different genres and two main storytelling approaches, personalized and fictionalized storytelling, used to make sense of antimicrobial resistance and its complexities. The study contributes new knowledge about YouTube as a platform for health communication and the types of videos about antimicrobial resistance that gets most traffic. This is useful, not the least for public health experts working to improve communication strategies that target hard-to-reach media publics.

Download Full-text