scholarly journals Using Anther Culture Method for Flax Breeding Intensification

Author(s):  
Andra Miķelsone ◽  
Dace Grauda ◽  
Veneranda Stramkale ◽  
Reinis Ornicāns ◽  
Isaak Rashal

Flax breeding is a long and complicated process based on hybridization and following selection of the best plants. Because of possible occasional cross-pollination the development of genetically stable homozygous lines could last more than 15 years. For more rapid creating of initial material for flax breeding anther culture methods for producing doubled haploid (DH) lines could be used successfully. The goal of this study was to develop the best anther culture protocol for producing DH lines from hybrids included in Latvian flax breeding programme and to do preliminary field evaluation of obtained DH lines. F4 hybrids were used in the experiment. Method, most applicable for establishing of DH from anther cultures, was elaborated; 13 DH lines were obtained during the experiment. Such agronomic important traits, as vegetation period, total plant height, number of seed vessels, number of seeds in a seed vessel, 1000 seeds weight, oil and bast fibre content were evaluated for obtained DH lines. Several accessions showed high 1000 seeds weight, number of seeds in a seed vessel, good oil and bast fibre content. It was concluded that anther culture method is of value of using as an adjunct to classical methods of flax breeding.

1998 ◽  
Vol 78 (4) ◽  
pp. 537-544 ◽  
Author(s):  
D. B. Dewan ◽  
G. Rakow ◽  
R. K. Downey

The production of doubled haploid (DH) lines of Brassica rapa could be an efficient procedure for the development of inbred parents for hybrid production. A total of 162 B. rapa DH lines were evaluated in field tests at Saskatoon, Canada, in single row, replicated tests and 10 DH lines were tested in four-row plot, multilocation, replicated tests. Seed of DH lines was produced by bud selfing in the greenhouse. Approximately one-fifth of all DH lines tested were chlorophyll deficient, presumably due to the expression of recessive alleles. Inbreeding depression was evident in low seed and biological yields, low number of seeds per pod and delayed flowering. Seed yield of DH lines was positively associated with the number of seeds per pod, early flowering and a long pod-filling period. One DH line was equal in yield to its donor population (DP), suggesting that dominance deviation was the genetic basis for high seed yield in this species. The consistent performance of DH lines over years and locations indicated that DH lines may be selected after 1 year of evaluation for combining ability testing. Higher yielding DH lines of B. rapa must be selected before they can be used as parents for hybrid development. Key words: Brassica rapa, doubled haploid, field evaluation


Animals ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 20
Author(s):  
Luigi De Grossi ◽  
Davide Santori ◽  
Antonino Barone ◽  
Silvia Abbruzzese ◽  
Matteo Ricchi ◽  
...  

Paratuberculosis is a chronic disease of ruminants caused by Mycobacterium avium subsp. Paratuberculosis (MAP). Since isolation of MAP type I (S) is rarely reported in Italy, our research was aimed at isolating, by an inexpensive liquid culture manual method, this type of MAP isolates. At first, we used an ELISA to point out to serologically positive samples from five flocks. Secondly, we used a fecal direct IS900-qPCR on the ELISA positive samples, in order to detect shedder animals. Feces from IS900-qPCR positive samples were inoculated in solid and liquid culture media. IS900-qPCR was further used to test the growth of MAP isolates in liquid medium, which were further confirmed by f57-qPCR and submitted to typing by specific PCR in order to identify the MAP type. Twenty-eight samples (24 fecal and four tissutal samples) were processed by culture methods, resulting in the isolation of six type I MAP field isolates. Notably, no isolates were recovered by solid media, underlining the utility of this liquid method. Few data about this type of MAP are currently available in Italy, and further analyses should be carried out in order to study the origin and epidemiology of type I strains circulating in Italy.


2012 ◽  
Vol 75 (4) ◽  
pp. 743-747 ◽  
Author(s):  
BWALYA LUNGU ◽  
W. DOUGLAS WALTMAN ◽  
ROY D. BERGHAUS ◽  
CHARLES L. HOFACRE

Conventional culture methods have traditionally been considered the “gold standard” for the isolation and identification of foodborne bacterial pathogens. However, culture methods are labor-intensive and time-consuming. A Salmonella enterica serotype Enteritidis–specific real-time PCR assay that recently received interim approval by the National Poultry Improvement Plan for the detection of Salmonella Enteritidis was evaluated against a culture method that had also received interim National Poultry Improvement Plan approval for the analysis of environmental samples from integrated poultry houses. The method was validated with 422 field samples collected by either the boot sock or drag swab method. The samples were cultured by selective enrichment in tetrathionate broth followed by transfer onto a modified semisolid Rappaport-Vassiliadis medium and then plating onto brilliant green with novobiocin and xylose lysine brilliant Tergitol 4 plates. One-milliliter aliquots of the selective enrichment broths from each sample were collected for DNA extraction by the commercial PrepSEQ nucleic acid extraction assay and analysis by the Salmonella Enteritidis–specific real-time PCR assay. The real-time PCR assay detected no significant differences between the boot sock and drag swab samples. In contrast, the culture method detected a significantly higher number of positive samples from boot socks. The diagnostic sensitivity of the real-time PCR assay for the field samples was significantly higher than that of the culture method. The kappa value obtained was 0.46, indicating moderate agreement between the real-time PCR assay and the culture method. In addition, the real-time PCR method had a turnaround time of 2 days compared with 4 to 8 days for the culture method. The higher sensitivity as well as the reduction in time and labor makes this real-time PCR assay an excellent alternative to conventional culture methods for diagnostic purposes, surveillance, and research studies to improve food safety.


2018 ◽  
Vol 2018 ◽  
pp. 1-3
Author(s):  
Carol E. Muenks ◽  
Patrick G. Hogan ◽  
Carey-Ann D. Burnham ◽  
Stephanie A. Fritz

Given the lack of standardization of methodologies for microbial recovery from built environments, we sought to compare the yield of Staphylococcus aureus with a broth enrichment method when incubated in agitated versus static conditions. Five unique strains of S. aureus at five different concentrations were cultured to compare direct plating, agitated broth enrichment, and static broth enrichment culture methods. All samples were incubated at 35° in ambient air. The lowest concentration recovered across three replicates and five strains did not differ between culture methods (Fisher’s exact test, p=0.50); notably, recovery of S. aureus was equivalent between static and agitated broth incubation. When broth enrichment was used (both static and agitated), the burden of S. aureus growth was higher (by semiquantitative assessment of 4-quadrant streaking) compared to the direct plating culture method. Optimizing strategies for microbial recovery is essential, particularly in areas of lower biomass, given the paucity of research concerning microbial communities of built environments. The results of this study, in conjunction with other experiments investigating microbiomes of built environments, can help inform protocols for standardizing culturing methods within built environments.


2007 ◽  
Vol 70 (5) ◽  
pp. 1080-1087 ◽  
Author(s):  
V. M. BOHAYCHUK ◽  
G. E. GENSLER ◽  
M. E. McFALL ◽  
R. K. KING ◽  
D. G. RENTER

Conventional culture methods have traditionally been considered the “gold standards” for the isolation and identification of foodborne pathogens. However, culture methods are labor-intensive and time-consuming. We have developed a real-time PCR assay for the detection of Salmonella in a variety of food and food-animal matrices. The real-time PCR assay incorporates both primers and hybridization probes based on the sequence of the Salmonella invA gene and uses fluorescent resonance energy transfer technology to ensure highly sensitive and specific results. This method correctly classified 51 laboratory isolates of Salmonella and 28 non-Salmonella strains. The method was also validated with a large number of field samples that consisted of porcine feces and cecal contents, pork carcasses, bovine feces and beef carcasses, poultry cecal contents and carcasses, equine feces, animal feeds, and various food products. The samples (3,388) were preenriched in buffered peptone water and then selectively enriched in tetrathionate and Rappaport-Vassiliadis broths. Aliquots of the selective enrichment broths were combined for DNA extraction and analysis by the real-time PCR assay. When compared with the culture method, the diagnostic sensitivity of the PCR assay for the various matrices ranged from 97.1 to 100.0%, and the diagnostic specificity ranged from 91.3 to 100.0%. Kappa values ranged from 0.87 to 1.00, indicating excellent agreement of the real-time PCR assay to the culture method. The reduction in time and labor makes this highly sensitive and specific real-time PCR assay an excellent alternative to conventional culture methods for surveillance and research studies to improve food safety.


2020 ◽  
Author(s):  
Ming Wang ◽  
Aisi Fu ◽  
Ben Hu ◽  
Gaigai Shen ◽  
Ran Liu ◽  
...  

AbstractBACKGROUNDAs approximately 19% of global deaths are attributable to infectious diseases, early diagnosis of infection is very important to reduce mortality. Traditional infection detection strategies have limited sensitivity, detection range, and turnaround times; a detection technology that can simultaneously detect bacterial and fungal infections within 24 h is urgently need in clinical settings.METHODSWe developed nanopore targeted sequencing (NTS) for same-day simultaneous Diagnosis of fungal and bacterial infections. NTS was developed by amplification of 16s rRNA gene (for bacteria), IST1/2 gene (for fungal), and rpoB (for Mycobacterium spp.) using multiple primers, and sequenced by a real-time nanopore sequencing platform. An in-house bioinformatic analyze pipeline was used to diagnose the infectious pathogens by mapping the sequencing results with the constructed databases.RESULTSComparison of 1312 specimens from 1257 patients using NTS and culture method; NTS detected pathogens in 58.71% of specimens from patients, compared to 22.09% detected using the culture method. NTS showed significantly higher sensitivity than culture methods for many pathogens. Importantly, a turnaround time of <24 h for all specimens, and a pre-report within 6 h in emergency cases was possible in clinical practice. Modification of antibiotic therapy and maintenance of original anti-infection regimens in 51.52% (17/33) and 36.36% (12/33) of patients was in accordance with NTS results, and quantitative monitoring of clinical treatment effects was evaluated in four patients by continuous NTS tests.CONCLUSIONSApplication of NTS in clinically detected pathogens can improve targeted antibiotic treatment and therapeutic monitoring.


2008 ◽  
Vol 54 (9) ◽  
pp. 742-747 ◽  
Author(s):  
Shiyong Lin ◽  
Xinying Wang ◽  
Haoxuan Zheng ◽  
Zhengguo Mao ◽  
Yong Sun ◽  
...  

Our purpose was to establish a quick and accurate real-time PCR (rtPCR) method to detect Campylobacter jejuni directly from human diarrheal stool as an alternative to traditional culture methods. To determine the consistency of rtPCR and culture method, 256 clinical diarrheal stool samples and 50 normal stool samples from healthy individuals were examined, and the whole process was double-blinded. Our data showed that the sensitivity of rtPCR in pure cultures and stool was 102CFU·mL–1and 103CFU·g–1, respectively. Of the 256 diarrheal samples, 10 specimens were successfully detected by both methods, whereas two specimens were PCR positive but culture negative. No positive results were found by these two methods in 50 normal specimens. Our data suggested that rtPCR was convenient in operation and time-saving (turnaround time 3.5–4 h), so it could be used for clinical diagnostic and epidemiological purposes.


2013 ◽  
Vol 37 (2) ◽  
pp. 156-160
Author(s):  
Mohammed J. Alwan

     The aim of this study was to determine the percentage of borne tuberculin infection in milk sample by using PCR.  (102) milk samples were collected from  cows , AL-Dejella (39) samples,  AL-Suara (20) samples cow station, AL-Fthalia (20) samples,  AL-Azezia (11) samples and AL-Twarege (12) samples (Iraq) during the period  July 10th   2010 to  Nov.30th   2010. The samples were examined by direct smear stained by Ziehle-Neelson stain, culture methods and confirmed the isolates by Polymerase Chain Reaction (PCR) assay. The results showed that  5, 102 (4.9%) milk samples were M. bovis positive that were detected by direct milk smear method and 10 out 102(9.8%) M.bovis +ve were detected by culture method and PCR assay. The results also showed that high percentage of bacterial isolates from milk samples AL-Dejella city show (12.8%) by culturing and PCR method followed by AL-Suara (10%), AL-Fthelia (10%), Al-Twarege (8.3%) but no bacterial isolation was recorded in AL-Azezia milk samples. This study concluded that M.bovis infection was spreading in dairy cow within the mentioned areas and PCR was more sensitive, rapid, and accurate technique for M.bovis infection diagnosis.


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