scholarly journals First Report of Black Rot of Cauliflower and Kale Caused by Xanthomonas campestris pv. campestris in Yugoslavia

Plant Disease ◽  
1999 ◽  
Vol 83 (10) ◽  
pp. 965-965 ◽  
Author(s):  
A. Obradović ◽  
M. Arsenijević
Keyword(s):  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Black Rot ◽  
Triphenyl Tetrazolium Chloride ◽  
American Phytopathological Society ◽  
Tetrazolium Chloride ◽  
Gram Negative ◽  
First Occurrence ◽  
Dark Green ◽  
Xanthomonas Campestris Pv Campestris

In Yugoslavia, Xanthomonas campestris pv. campestris was isolated from forage kale in 1964 and cabbage in 1997 (1). Recently, the incidence and severity of black rot symptoms on cabbage, cauliflower, and kale have increased. Gram-negative, rod-shaped, motile bacteria were isolated from the diseased leaf and vascular tissues of cauliflower and kale plants collected from 1995 to 1998. The isolates formed yellow, convex, mucoid colonies on yeast dextrose chalk medium, metabolized glucose oxidatively, grew at 37°C, hydrolyzed gelatin and esculin, produced acids from d-arabinose, glucose, sucrose, and trehalose, and did not reduce nitrates. They were nonfluorescent, amylolytic and pectolytic, oxidase negative and catalase positive, and tolerant to 5% NaCl but not to 0.1% triphenyl tetrazolium chloride. Koch's postulates were completed by injecting bacterial suspensions (108 CFU/ml) into leaf petioles of cabbage, cauliflower, and kale seedlings (2- to 3-leaf stage). Dark green watersoaking of petioles and leaf veins followed by yellowing and collapse of inoculated plants was observed after 3 to 5 days. When compared with published information (2), the isolates were identified as X. campestris pv. campestris. This is the first occurrence of this bacterium in cauliflower and kale in Yugoslavia. References: (1) O. Jovanovic et al. Plant Prot. Belgrade 221:175, 1997. (2) N. W. Schaad. 1988. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 2nd ed. The American Phytopathological Society, St. Paul, MN.

scholarly journals Recent Outbreaks of Black Rot of Brassicas Caused by Xanthomonas campestris pv. campestris in Southern Mozambique

Plant Disease ◽  
2009 ◽  
Vol 93 (11) ◽  
pp. 1218-1218
Author(s):  
J. Bila ◽  
A. M. Mondjana ◽  
E. G. Wulff ◽  
C. N. Mortensen
Keyword(s):  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Identification System ◽  
Black Rot ◽  
Microbial Identification ◽  
Brassica Spp ◽  
Brassica Crop ◽  
Leaf Tissues ◽  
Pathogenicity Tests ◽  
Xanthomonas Campestris Pv Campestris

In August and September of 2007, black rot symptoms were observed on seedbed and field plants of Brassica spp. grown in the southern districts of Boane, Mahotas, and Chòkwé in Mozambique. One hundred eighty-two cabbage-growing households were evaluated for the incidence of Xanthomonas campestris pv. campestris. Five Brassica cultivars, Glory F1, Glory of Enkhuizen, Copenhagen Market, Starke (Brassica oleracea pv. capitata L.), and Tronchuda (B. oleracea L. var. costata DC) were grown in the areas for several years. The hybrid Glory F1 was the most popular grown cultivar in the surveyed areas. In the Boane district, the highest incidence of black rot was recorded on Copenhagen Market (70%), Starke (67.9%), and Glory F1 (67.3%). In Chòkwé, Tronchuda (Portuguese kale) was the least affected Brassica crop. Water-soaked lesions starting at the edge of leaves with typical V-shaped necrotic lesions and vein discoloration were the most commonly observed symptoms. When examined with a microscope, cut edges of symptomatic stem and leaf tissues consistently exhibited bacterial streaming. The bacteria were isolated from commercial seed and field-grown plants on semiselective agar media (2). Forty-six X. campestris pv. campestris strains that were gram negative, aerobic, starch positive, nitrate negative, and oxidase negative or weakly positive (3) were further identified on the basis of ELISA (Agdia Inc., Elhart, IN), GN Biolog Microbial Identification System, version 4.2 (Biolog Inc., Hayward, CA), and PCR-specific primers (1). Pathogenicity tests were conducted by pin inoculating two upper leaves of cabbage (cv. Wirosa) in the 2- to 3-leaf stage with bacterial growth from 24-h-old agar cultures (2). Black rot symptoms developed on nearly all inoculated plants within 7 to 14 days. No symptoms were observed on control plants inoculated with a sterile pin without bacterial inoculum. The severity of black rot of Brassica spp. in three important farming districts caused significant losses in Mozambique. References: (1) T. Berg et al. Plant Pathol. 54:416, 2005. (2) S. J. Roberts and H. Koenraadt. Page 1 in: International Rules for Seed Testing: Annexe to Chapter 7 Seed Health Methods. ISTA, 2007. (3) N. W. Schaad et al. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001.

scholarly journals First Report of Black Rot on Arugula Caused by Xanthomonas campestris pv. campestris in Argentina

Plant Disease ◽  
2008 ◽  
Vol 92 (6) ◽  
pp. 980-980 ◽  
Author(s):  
A. M. Romero ◽  
R. Zapata ◽  
M. S. Montecchia
Keyword(s):  
Xanthomonas Campestris ◽  
Pathogenic Bacteria ◽  
Biochemical Characterization ◽  
Bacterial Suspension ◽  
Black Rot ◽  
Strictly Aerobic ◽  
First Report ◽  
Plastic Bags ◽  
Water Plants ◽  
Xanthomonas Campestris Pv Campestris

During the fall of 2005, arugula (Eruca sativa Mill.) plants grown in experimental field plots in Buenos Aires, Argentina presented V-shaped necrotic lesions on leaf margins and blackened veins with broad yellow halos, followed by leaf necrosis. At flowering, 96% of the plants were affected with 27% of the leaves with symptoms. Yellow, round, mucoid, convex, bacterial colonies were isolated from several leaves on yeast dextrose chalk agar. Two strains were further studied. Xanthomonas campestris pv. campestris Xcc8004 was used as a control. Strains were gram negative, rod shaped, strictly aerobic, catalase-positive, oxidase and urease-negative, hydrolyzed starch, gelatine and aesculin, and did not reduce nitrate (2). Pathogenicity was tested by spraying 10 3-week-old arugula plants with either a bacterial suspension (107 CFU/ml) or sterile water. Plants were placed in plastic bags for 72 h after inoculation. All inoculated plants showed necrotic lesions enlarging from the margin of the leaves 7 days after inoculation. No lesions were observed on control plants. On the basis of biochemical characterization (2) and genomic fingerprints generated by BOX-PCR (1), the pathogen was identified as X. campestris pv. campestris. To our knowledge, this is the first report of X. campestris pv. campestris causing black rot on arugula in Argentina. References: (1) J. L. Rademaker et al. Int. J. Syst. Evol. Microbiol. 50:665, 2000. (2) N. W. Schaad et al. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society, St. Paul, MN, 2001.

Improved control of black rot of broccoli caused by Xanthomonas campestris pv. campestris using a bacteriophage and a nonpathogenic Xanthomonas sp. strain

2017 ◽  
Vol 83 (6) ◽  
pp. 373-381 ◽  
Author(s):  
Hirofumi Nagai ◽  
Noriyuki Miyake ◽  
Shinro Kato ◽  
Daisuke Maekawa ◽  
Yasuhiro Inoue ◽  
...  
Keyword(s):  
Xanthomonas Campestris ◽  
Black Rot ◽  
Xanthomonas Campestris Pv Campestris

scholarly journals Antagonism of yeasts to Xanthomonas campestris pv. campestris on cabbage phylloplane in field

1999 ◽  
Vol 30 (3) ◽  
pp. 191-195 ◽  
Author(s):  
Sayonara M.P. Assis ◽  
Rosa L.R. Mariano ◽  
Sami J. Michereff ◽  
Gil Silva ◽  
Elizabeth A.A. Maranhão
Keyword(s):  
Disease Severity ◽  
Xanthomonas Campestris ◽  
Antagonistic Activity ◽  
Black Rot ◽  
Significant Difference ◽  
Xanthomonas Campestris Pv Campestris

Twenty yeast isolates, obtained from cabbage phylloplane, were evaluated for antagonistic activity against Xanthomonas campestris pv. campestris, in field. Plants of cabbage cv. Midori were pulverized simultaneously with suspensions of antagonists and pathogen. After 10 days, plants were evaluated through percentage of foliar area with lesions. Percentage of disease severity reduction (DSR%) was also calculated. Yeast isolates LR32, LR42 and LR19 showed, respectively, 72, 75 and 79% of DSR. These antagonists were tested in seven different application periods in relation to pathogen inoculation (T1=4 d before; T2=simultaneously; T3=4 d after; T4=4 d before + simultaneously; T5=4 d after + simultaneously; T6=4 d before + 4 d after; T7=4 d before + simultaneously + 4 d after). The highest DSRs were showed by LR42 (71%), LR42 (67%), LR35 (69%) and LR19 (68%) in the treatments T7, T4, T5 and T6, which significantly differed from the others. The same yeast antagonists were also tested for black rot control using different cabbage cultivars (Fuyutoyo, Master-325, Matsukaze, Midori, Sekai I and Red Winner). The DSRs varied from 58 to 61%, and there was no significant difference among cultivars.

scholarly journals Characterization of Xanthomonas campestris pv. campestris in Algeria

2021 ◽  
Vol 60 (1) ◽  
pp. 51-62
Author(s):  
Samia LAALA ◽  
Sophie CESBRON ◽  
Mohamed KERKOUD ◽  
Franco VALENTINI ◽  
Zouaoui BOUZNAD ◽  
...  
Keyword(s):  
Xanthomonas Campestris ◽  
Housekeeping Genes ◽  
First Record ◽  
Black Rot ◽  
Physiological And Biochemical Characteristics ◽  
Main Production ◽  
Production Areas ◽  
Cruciferous Plants ◽  
Xanthomonas Campestris Pv Campestris

Xanthomonas campestris pv. campestris (Xcc) causes the black rot of cruciferous plants. This seed-borne bacterium is considered as the most destructive disease to cruciferous crops. Although sources of contamination are various, seeds are the main source of transmission. Typical symptoms of black rot were first observed in 2011 on cabbage and cauliflower fields in the main production areas of Algeria. Leaf samples displaying typical symptoms were collected during 2011 to 2014, and 170 strains were isolated from 45 commercial fields. Xcc isolates were very homogeneous in morphological, physiological and biochemical characteristics similar to reference strains, and gave positive pathogenicity and molecular test results (multiplex PCR with specific primers). This is the first record of Xcc in Algeria. Genetic diversity within the isolates was assessed in comparison with strains isolated elsewhere. A multilocus sequence analysis based on two housekeeping genes (gyrB and rpoD) was carried out on 77 strains representative isolates. The isolates grouped into 20 haplotypes defined with 68 polymorphic sites. The phylogenetic tree obtained showed that Xcc is in two groups, and all Algerian strains clustered in group 1 in three subgroups. No relationships were detected between haplotypes and the origins of the seed lots, the varieties of host cabbage, the years of isolation and agroclimatic regions.

Involvement of a novel peroxidase isozyme and lignification in hydathodes in resistance to black rot disease in cabbage

2000 ◽  
Vol 78 (9) ◽  
pp. 1144-1149 ◽  
Author(s):  
P A Gay ◽  
S Tuzun
Keyword(s):  
Xanthomonas Campestris ◽  
Virulent Strain ◽  
Black Rot ◽  
Peroxidase Isozyme ◽  
Anionic Peroxidase ◽  
Peroxidase Isozymes ◽  
Resistant Varieties ◽  
Rot Disease ◽  
Xanthomonas Campestris Pv Campestris ◽  
Lignin Deposition

The physiological mechanisms associated with resistance of cabbage to black rot disease seem to be associated with the hydathodes. To investigate the role of hydathodes in disease resistance, total peroxidase activities, anionic peroxidase isozyme expression, and lignin deposition were determined in hydathodes of resistant (Hancock and Green Cup), partially resistant (Cheers), and susceptible (Strukton and Perfect Ball) cabbage varieties (Brassica oleracea L.) during pathogenesis with Xanthomonas campestris pv. campestris. Four-week-old plants were petiole-inoculated with a highly virulent strain of X. campestris pv. campestris (FD91L). Hydathodal fluids were collected daily over a 14-day period from infected plants as well as noninfected, mock-inoculated control plants. Hydathodal fluids of resistant varieties had greater peroxidase activity when compared to susceptible ones, with infected plants having higher peroxidase levels than noninfected plants. Isoelectric focusing revealed the presence of four anionic peroxidase isozymes in hydathodal fluids, with the most anionic one (pI of 3.6) accumulating only upon infection. Lignin deposition in and around the hydathodes was associated with the accumulation of this particular isozyme in hydathodal fluids. The evidence suggests that a rapid, systemic response is associated with resistance to the bacterial pathogen.Key words: peroxidases, hydathodes, isozymes, black rot disease, cabbage, Xanthomonas campestris pv. campestris.

Sign in / Sign up

Export Citation Format

Share Document