Response of Xanthomonas citri pv. malvacearum isolates to cotton differing in susceptibility to the bacterium and their predicted type III effectors.

Author(s):  
Terry A Wheeler ◽  
Taylor Harris ◽  
Rebecca Bart ◽  
Jason Woodward ◽  
Thomas Isakeit ◽  
...  

From 2015 to 2020, 342 isolates of Xanthomonas citri pv. malvacearum (Xcm) were obtained from cotton fields in Texas, including 64 isolates collected from symptomatic cultivars that were thought to be resistant to race 18 strains of Xcm (the predominant race in the USA). Symptoms on highly resistant cultivars prompted concern that a new race of Xcm was present. The 342 isolates were inoculated on a race 18 susceptible (DP 1747NR B2XF) and race 18 resistant (S295) cotton cultivar and none of the isolates caused blight type symptoms (water soaking and chlorosis) on S295, indicating that the B12 resistant gene was still beneficial for disease management. Four cultivars, varying in their field response to bacterial blight, were inoculated with each of 17 isolates of Xcm and the incidence of plants exhibiting bacterial blight symptoms averaged 87% for DP 1747NR B2XF, 51% for partially susceptible NG 4936 B3XF, 16% for partially resistant DP 1646 B2XF, and 0% for S295. Xcm isolates from Texas (11), Georgia (1) and Oklahoma (1) were sequenced, and their type three effectors (T3Es) were predicted. All isolates (GA, OK, TX) had the same T3E proteins as previously identified Xcm race 18 isolates (tested for 25 genes), including XopJ. Race 1, 2, 3, and 12 of Xcm included in the comparisons were all missing the XopJ gene. Use of cultivars with the B12 gene is an effective strategy to manage bacterial blight of cotton.

2022 ◽  
Vol 8 ◽  
Author(s):  
Maéva Zysman ◽  
Chantal Raherison-Semjen

Chronic obstructive pulmonary disease (COPD) is no longer a respiratory disease that predominantly affects men, to the point where the prevalence among women has equaled that of men since 2008, partly due to their increasing exposure to tobacco and to biomass fuels. Indeed, COPD has become the leading cause of death in women in the USA. A higher susceptibility of female to smoking and pollutants could explain this phenomenon. Besides, the clinical presentation appears different among women with more frequent breathlessness, anxiety or depression, lung cancer (especially adenocarcinoma), undernutrition and osteoporosis. Quality of life is also more significantly impaired in women. The theories advanced to explain these differences involve the role of estrogens, smaller bronchi, impaired gas exchange in the lungs and smoking habits. Usual medications (bronchodilators, ICS) demonstrated similar trends for exacerbation prevention and lung function improvement in men and women. There is an urgent need to recognize the increasing burden of COPD in women and therefore to facilitate global improvements in disease management (smoking cessation, pulmonary rehabilitation…) in half of the population. Nevertheless, important limitations to the treatment of women with COPD include greater under-diagnosis than in men, fewer spirometry tests and medical consultations. In conclusion there is an urgent need to recognize the increasing burden of COPD in women and therefore to facilitate globally improvements in disease management in this specific population.


Plant Disease ◽  
2019 ◽  
Vol 103 (3) ◽  
pp. 422-429 ◽  
Author(s):  
Xiao-Qiang Wang ◽  
Tom W. Allen ◽  
Hui Wang ◽  
Daniel G. Peterson ◽  
Robert L. Nichols ◽  
...  

Bacterial blight, historically a seed-borne disease of cotton (Gossypium hirsutum) is caused by Xanthomonas citri pv. malvacearum, resulted in significant economic losses prior to development of resistant varieties and implementation of acid-delinting of planting seed. Periodic outbreaks have been associated with seed since the early twentieth century; of note, the disease has experienced a resurgence since 2011. Effective management of bacterial blight is dependent on accurate diagnosis and detection of the pathogen. Currently, detection of X. citri pv. malvacearum is performed by time-consuming microbiological methods. In this study, a novel and sensitive TaqMan-based qPCR protocol was developed to test for X. citri pv. malvacearum in cotton plant tissue. The primers developed are specific to five races of X. citri pv. malvacearum, but not to other Xanthomonas species or cotton-associated nonpathogenic bacteria. The efficiency of this assay was evaluated on artificially inoculated cotton leaves and seed, on naturally infected cotton leaves, and on bolls and seed originating from bacterial blight symptomatic bolls. The protocol’s efficiency from artificially inoculated plant tissue was 102 copies g−1 and 37 copies from 1 g seed for leaves and seed, respectively. In addition, X. citri pv. malvacearum was detected from 94% of the seed samples originating from blight symptomatic bolls. The qPCR protocol provides a rapid and accurate method for diagnosis and detection of bacterial blight and offers a tool for monitoring X. citri pv. malvacearum and potentially reducing its spread in seed.


2014 ◽  
Vol 104 (10) ◽  
pp. 1088-1097 ◽  
Author(s):  
Margaret Essenberg ◽  
Melanie B. Bayles ◽  
Margaret L. Pierce ◽  
Laval M. Verhalen

Near-isogenic lines of upland cotton (Gossypium hirsutum) carrying single, race-specific genes B4, BIn, and b7 for resistance to bacterial blight were used to develop a pyramid of lines with all possible combinations of two and three genes to learn whether the pyramid could achieve broad and high resistance approaching that of L. A. Brinkerhoff's exceptional line Im216. Isogenic strains of Xanthomonas axonopodis pv. malvacearum carrying single avirulence (avr) genes were used to identify plants carrying specific resistance (B) genes. Under field conditions in north-central Oklahoma, pyramid lines exhibited broader resistance to individual races and, consequently, higher resistance to a race mixture. It was predicted that lines carrying two or three B genes would also exhibit higher resistance to race 1, which possesses many avr genes. Although some enhancements were observed, they did not approach the level of resistance of Im216. In a growth chamber, bacterial populations attained by race 1 in and on leaves of the pyramid lines decreased significantly with increasing number of B genes in only one of four experiments. The older lines, Im216 and AcHR, exhibited considerably lower bacterial populations than any of the one-, two-, or three-B-gene lines. A spreading collapse of spray-inoculated AcBIn and AcBInb7 leaves appears to be a defense response (conditioned by BIn) that is out of control.


HortScience ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 888a-888 ◽  
Author(s):  
James D. McCreight ◽  
Michael D. Coffey ◽  
Thomas A. Turini ◽  
Michael E. Matheron

Races 1 and 2 of Podosphaera xanthii (syn. Sphaerotheca fuliginea) were defined in Imperial Valley, Calif. 1938 when P. xanthii overcame genetic resistance in `PMR 45'. Race 3 was first observed in the U.S. in 1976 in Texas; 15 additional races of P. xanthii have been reported in the literature since 1996. Races 1 and 2 have been common in Arizona and California based upon the effectiveness of the powdery mildew resistance genes in commercially available melon cultivars grown in these states. Field data from 11 commonly used melon P. xanthii race differentials in 2001 and 2002 indicated the presence of race 1 in the Imperial Valley and San Joaquin Valley of California, and Yuma, Arizona. In spring 2003, the powdery mildew race situation changed. The first evidence was the occurrence of a severe and widespread infection of powdery mildew in a commercial cantaloupe field. The 11 powdery mildew race differentials were susceptible to powdery mildew in a nearby replicated field test. PI 313970, a melon from India, was resistant to this apparent new race of powdery mildew.


Medicina ◽  
2019 ◽  
Vol 55 (12) ◽  
pp. 785
Author(s):  
Nicola Luigi Bragazzi

Background and Objectives: Nanomedicine, a term coined by the American engineer Eric Drexler (1955) and Robert Freitas Jr. (1952) in the nineties, can be defined as a complex, multi-disciplinary branch of medicine, in which nano-technologies, molecular biotechnologies, and other nano-sciences are applied at every step of disease management, from diagnosis (nano-diagnostics) to treatment (nano-therapeutics), prognosis, and monitoring of biological parameters and biomarkers. Nanomedicine is a relatively young discipline, which is increasingly and exponentially growing, characterized by emerging ethical issues and implications. Nanomedicine has branched out in hundreds of different sub-fields. Materials and Methods: A bibliometrics-based analysis was applied mining the entire content of PubMed/MEDLINE, using “nanomedicine” as a Medical Subject Heading (MeSH) search term. Results: A sample of 6696 articles were extracted from PubMed/MEDLINE and analyzed. Articles had been published in the period from 2003 to 2019, showing an increasing trend throughout the time. Six thematic clusters emerged (first cluster: molecular methods; second cluster: molecular biology and nano-characterization; third cluster: nano-diagnostics and nano-theranostics; fourth cluster: clinical applications, in the sub-fields of nano-oncology, nano-immunology and nano-vaccinology; fifth cluster: clinical applications, in the sub-fields of nano-oncology and nano-infectiology; and sixth cluster: nanodrugs). The countries with the highest percentages of articles in the field of nanomedicine were the North America (38.3%) and Europe (35.1%). Conclusions: The present study showed that there is an increasing trend in publishing and performing research in the super-specialty of nanomedicine. Most productive countries were the USA and European countries, with China as an emerging region. Hot topics in the last years were nano-diagnostics and nano-theranostics and clinical applications in the sub-fields of nano-oncology and nano-infectiology.


2020 ◽  
Vol 4 (2) ◽  
Author(s):  
Hatem A Hejaz ◽  
Ameera Zalloum ◽  
Bara’a Shalaldeh ◽  
Taima’ Alnatsheh ◽  
Rozan Attili

Objective: Coronavirus is a positive-strand RNA virus in which consists of a certain virus that infects both animals and humans; including the recent one which is known as severe acute respiratory syndrome coronavirus (SARS-CoV). Coronavirus has been a significant threat in November 2019. Methods: The review focus on full coverage of the epidemic state of the virus worldwide, major diagnostic approaches used, the therapeutic drugs types and approaches used, the pathology and pathogenesis of the disease in infected patients and its consequences in addition to the virus and the major guidelines for the disease management in different countries. Different literature and guidelines among different databases were searched. Literature reviewing was conducted using the following search engines, Google Scholar, Medline, Pub Med, Web of Science, and Science Direct, so in order to better reveal the published peer-reviewed articles about  SARS-CoV, MERS-CoV, and 2019-nCoV. Results: SARS-CoV data collected in this review will give help to medical researchers and further decision-makers, social and economic makers concerned with health status, and pandemic infections among countries in different aspects. As understanding, the disease and the different responses to this virus could help to find immune-based therapeutics or/ and traditional medicines. By June 1st2020, the pandemic cases are about six million worldwide and the number is rising everyday sharply. While the actual and accurate causes and effective treatment of COVID-19 are still unknown or unavailable and the number of active cases of the infection is rising every day which rising panic and concern on public health worldwide. The greatest number of new cases and deaths of COVID-19 were reported in the USA, Brazil, Russia, Spain, the UK, Italy, Germany, and France. This growing number of cases is due to the person-to-person transmission that has been reported both in and outside of China. In Palestine, the pandemic cases were about 600 by the end of May 2020. In June 28th 2020 coronavirus cases were 10,088,576, deaths 501,442, and recovered 5,466,534 globally. The cases increased very sharply within a short period (about three weeks); in Palestine, the spread of the disease is also nearly tripled by this time (1,815 cases reported). The outbreak of the disease is extremely very fast as by the end of June (within only one month period), the cases have been nearly doubled as the coronavirus cases confirmed were 10,690,566, deaths 516,393 (8%), and recovered are 5,856,464 worldwide. The high incidence rate and cases were also in the USA (2,751,571), then Brazil (1,426,913), Russia (654,405), etc. In Palestine by this time, at the end of June, the reported cases were increased very sharply by about six times; as more than 3,095 cases were reported including East Jerusalem (337 cases), with 11 deaths. The highest cases (1947 cases) were in Hebron Governorate; with these confirmed cases Palestine ranked 97 among 215 countries that have coronavirus; with the highest outbreak rate in the world; compare to population number. Conclusions: The pandemic by COVID-19 is a very dangerous issue affecting people worldwide. Without fundamental therapeutic interventions, current management is to reduce the virus spread and provide supportive care for diseased patients. There is an urgent need to develop targeted therapies. Understanding the disease and the different responses to this virus could help to find immune-based therapeutics or/ and traditional medicines. It is important to have the latest information but we must ensure that information is coming from trustworthy sources. We have collected a variety of helpful resources related to COVID-19. We also have several initiatives to get the public involved in our work and educated on how to make informed health decisions. The global impact of this new pandemic is yet uncertain.


Plant Disease ◽  
2020 ◽  
Vol 104 (1) ◽  
pp. 198-203
Author(s):  
Bruna Alicia Rafael de Paiva ◽  
Adriane Wendland ◽  
Nara Cristina Teixeira ◽  
Marisa A. S. V. Ferreira

A single loop-mediated isothermal amplification (LAMP) assay was developed for specific detection of both pathogens that cause bacterial blight in common bean, Xanthomonas phaseoli pv. phaseoli (Xpp) and Xanthomonas citri pv. fuscans (Xcf). The objective was to provide a simple, easy-to-use, specific, and sensitive method to investigate the presence of one or both pathogens in plant material and seeds for routine diagnosis. The detection limits for both pathogens were 10 CFU/ml for cell suspensions and 1 fg of DNA, whereas in conventional PCR, the primers detected up to 105 CFU/ml and 1 ng of DNA. Specificity was confirmed by testing DNA from bean leaves, other Xanthomonas species, common fungal and bacterial bean pathogens, and bacteria from the leaf microbiota. The method was tested with bean leaves inoculated with Xpp, and the pathogen could be detected from 4 h up to 15 days postinoculation, even before disease symptoms were visible. When the method was applied to bacterium detection (Xpp or Xcf) in seed lots from infected plants, the bacterium detection rate was 100% (24 of 24). The pathogens were detected in seeds incubated for just 1 h in saline solution (0.85%), reducing the time needed for bacterium detection. The LAMP assay could be useful as a tool in bean bacterial blight management. Rapid and sensitive detection of bacteria in bean seed lots would reduce the risks of planting highly contaminated seeds in environments favorable to blight multiplication.


2017 ◽  
Vol 5 (36) ◽  
Author(s):  
Mylène Ruh ◽  
Martial Briand ◽  
Sophie Bonneau ◽  
Marie-Agnès Jacques ◽  
Nicolas W. G. Chen

ABSTRACT Xanthomonas citri pv. vignicola strains cause bacterial blight of the legume crop cowpea. We report whole-genome sequences of three X. citri pv. vignicola strains obtained using PacBio single-molecule real-time sequencing. Such genomic data provide new information on pathogenicity factors, such as transcription activator-like effectors.


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