Multiplex PCR Protocol Research Articles

Development of molecular diagnostic protocols for simultaneous identification of common bed bugs (Cimex lectularius) and tropical bed bugs (Cimex hemipterus)

BackgroundThe resurgence of two bed bug species, the common bed bug (Cimex lectularius Linnaeus, 1758) and tropical bed bug (Cimex hemipterus Fabricius, 1803), in the same geographical regions has been frequently reported recently. Consequently, the rapid identification of these species is crucial for implementing targeted capture traps and tailored pyrethroid resistance diagnosis, due to differences in genetic and physiological traits.MethodsTo develop molecular diagnostic methods, distinct protocols were established for multiplex PCR and loop-mediated isothermal amplification (LAMP) using species-specific primers based on species-specific segments of internal transcribed spacer 2 sequences. These methods were optimized for rapid and accurate identification of the two bed bug species.ResultsBoth multiplex PCR and LAMP protocols were effective in simultaneously identifying the two bed bug species, even when utilizing DNA released from dead specimens. Notably, the straightforward procedure and minimal time commitment of LAMP suggest its potential for rapid and accurate diagnosis of bed bugs in the field. The diagnostic accuracy of these methods was validated through a blind test.ConclusionsThe multiplex PCR and LAMP protocols lay the foundation for rapid and accurate field identification of bed bug species, enabling the use of appropriate traps and the detection of species-specific pyrethroid resistance mutations. This approach ensures effective management tailored to the unique characteristics of each bed bug species.Graphical

Molecular Survey of Parasitic Contamination of Frozen Berries.

Berries represent healthy dietary options and contain bioactive compounds associated with a decreased risk of diseases. Despite representing healthy food choices, these products can be contaminated by pathogenic microorganisms, including parasites. Among foodborne parasites, Giardia duodenalis, Cryptosporidium parvum, Cyclospora cayetanensis, Toxoplasma gondii, and Echinococcus multilocularis are of significant public health importance and have been recently detected in fresh berries in Europe, including Italy. Berries can be purchased fresh or frozen, and it is worrying that even frozen berries could represent a risk for the consumer. In fact, several parasites can resist freezing temperatures and have been responsible for outbreaks of infection. The aim of this study was to investigate the presence of G. duodenalis, C. parvum, C. cayetanensis, T. gondii, and E. multilocularis in frozen berries with simplex and multiplex real-time PCR protocols. A total of 108 packages of mixed frozen berries were bought from supermarkets located in a south-eastern region of Italy. The samples were tested using two simplex real-time PCR protocols targeting C. parvum and G. duodenalis, respectively, and a multiplex real-time PCR targeting C. cayetanensis, T. gondii, and E. multilocularis. None of the investigated parasites were detected in the frozen berry samples tested. This research topic is still unexplored and of great current interest. These results represent a first attempt to investigate parasitic contamination of frozen berries sold on the Italian market, but further large-scale surveys are required.

A Multiplex RT-PCR for the Detection of Three Viruses and One Viroid Infecting Hemp

Hemp ( Cannabis sativa L.) is an emerging industrial crop in the United States. In recent surveys of hemp growers, disease identification and management were determined to be significant priority areas for future research. From previous studies on disease identification in Western U.S. hemp production systems, hop latent viroid (HLVd), beet curly top virus (BCTV), Cannabis sativa mitovirus 1 (CasaMV1), and citrus yellow vein associated virus (CYVaV) were detected at high incidences. In the present study, a multiplex reverse transcription PCR protocol was developed to detect this viroid and viruses from hemp leaf samples simultaneously. Using the developed protocol, the multiplex reverse transcription PCR could detect each virus and viroid specifically in 10−1-diluted cDNA. The protocol was validated on 6 hemp metavirome leaf samples from field-grown hemp grown in 2019 and 23 uncharacterized leaf samples in 2021 from Colorado. Of the samples tested, 95% tested positive for CasaMV1 in 2021. This was greater than infections of BCTV (4%), HLVd (0%), and CYVaV (0%). Coinfections accounted for 4% of samples in 2021. This method offers sensitive, specific, and fast simultaneous detection of three viruses and one viroid from hemp, contributing to large-scale pathogen-free hemp certification schemes. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

Sensitivity Assessment of a Multiplex and Real-Time PCR Protocols for the Detection of Malaria in External Quality Control Samples in the Malaria Reference Center in Greece

Background: Accurate malaria diagnosis constitutes a challenging task, necessitating the need for the implementation of targeted and effective diagnostic tools. The purpose of the current study was to evaluate the effectiveness of two different molecular methodologies in terms of sensitivity for the detection of External Quality Assessment (EQA) Plasmodium samples. Methods: A total of 104 lyophilized blood samples from 14 different UK-NEQAS (National External Quality Assessment Site) (2016–2021) and eight WHO-NEQAS distributions (2017–2020) were analyzed. An in-house multiplex PCR protocol, followed by single target real-time PCR protocols for all five Plasmodium species, was implemented. Results: The multiplex PCR had a success rate of 10/16 and 20/28 for P. vivax and P. falciparum species, respectively. On the other hand, the respective results for real-time PCR had a success rate of 13/16 (P. vivax), 28/28 (P. falciparum), 5/8 (P. malariae), 8/10 (P. ovale), and 10/14 (P. knowlesi). Plasmodium falciparum samples displayed the highest sensitivity of detection, 0.02 parasites/μL. Plasmodium vivax samples displayed a 0.1 parasites/μL cutoff value, greater than the respective value for whole blood samples, while P. ovale species displayed a respective cutoff value of 0.05 parasites/μL. Due to the limited number of tested samples, data obtained for P. malariae and P. knowlesi species samples were inconclusive. Conclusions: Real-time PCR comprises a credible molecular methodology in terms of sensitivity assessment and detection of low parasitemia levels of Plasmodium sp. in EQA lyophilized blood samples.

Validation of a Forensic Method to be used in Food Fraud Investigation

Food fraud is the act in which food is purposefully mislabeled, adulterated, or contaminated, often to make up a percentage of a missing substance when the product is being made. It is often done purposefully to mislead consumers into thinking some ingredient is or is not present in the food, which can be hazardous to the consumer. This project aimed to validate a forensic domestic animal species reference ladder and multiplex PCR kit that can be used in animal investigations, with a focus on food fraud. A multiplex PCR protocol targeting mitochondrial DNA (mtDNA) markers and a species reference ladder can quickly identify DNA from chicken, cow, sheep, turkey, goat, horse, dog, and cat. To validate the kit, it was tested on five different brands of dog food, specifically four brands of kibble alongside a canned wet stew dog food. DNA extraction was performed using the QIAamp MinElute Column kit or the Qiagen EZ1 investigator kit, then DNA quantification, multiplex PCR, gel electrophoresis, and capillary electrophoresis to build species mtDNA profiles for each food’s contents. Results from one dog food kibble yielded some speculation as DNA for sheep and goat contents not listed in the ingredients were detected using both the gel and capillary electrophoresis.

A multiplex PCR assay to detect mislabelling in fish products

ABSTRACT Fish substitution in fish products is an important issue in fish markets, as it is a widespread practice. An authentication protocol for Rohu, Thaila and Tilapia was developed by multiplex PCR. Three species-specific and one degenerate common forward primer were designed using the Cytb gene of the mitochondrial genome. These primers for Labeo rohita, Labeo catla and Oreochromis niloticus showed the fragment size of 235 bp, 186 bp and 506 bp on the agarose gel, respectively. The primers for L. rohita and L. catla were sensitive to 0.1 ng of DNA template, while for O. niloticus this value was 1 ng of DNA template. A total of 230 commercial samples (160 fried and 70 processed fish products) were screened, where 60% mislabeling in fried and 30% mislabeling in processed fish were found. This multiplex PCR protocol could give useful insights for food inspection and enforcement of regulatory food control.

A foundation for comparative genomics and evolutionary studies in Nucella lapillus based on complete mitogenome assembly

The Atlantic dog whelk, Nucella lapillus, is a marine snail that exhibits divergent evolution in response to habitat adaptation, resulting in distinct populations at the phenotypic, genotypic, and karyotypic levels. In this study, we utilized short- and long-read NGS data to perform a de novo assembly of the entire mitochondrial genome of N. lapillus and developed a multiplex PCR protocol to sequence most of its length using ONT sequencing. Our analysis revealed a typical circular configuration of 16,474 bp in length with 13 protein-coding genes, 22 different tRNA genes, 2 of them showing two copies, 2 rRNA genes, and a control region. Long-read sequencing enabled us to identify a 1826 bp perfect inverted repeat within the control region. Comparative analysis of the mitogenomes of related species in the Muricidae family revealed a conserved gene configuration for N. lapillus. We found a low genetic diversity, as well as a moderate genetic differentiation among the studied populations. Interestingly, there was no observed differentiation between the two chromosomal races, suggesting either introgression and permanent incorporation of the mitochondrial DNA haplotype from one of the chromosomal races into the other or a slower evolutionary rate of the mtDNAs with respect to that of the karyotypes. Our study serves as a foundation for comparative genomics and evolutionary investigations in this species.

Three novel multiplex PCR assays for rapid detection of virulence, antimicrobial resistance, and toxin genes in Acinetobacter calcoaceticus-baumannii complex species.

The Acinetobacter calcoaceticus-baumannii (ACB) complex is an often-overlooked group of nosocomial pathogens with a significant environmental presence. Rapid molecular screening methods for virulence, antimicrobial resistance, and toxin (VAT) genes are required to investigate the potential pathogenicity of environmental isolates. This study aimed to develop and apply novel ACB complex-specific multiplex PCR (mPCR) primers and protocols for the rapid detection of eight VAT genes. We optimized three single-tube mPCR assays using reference DNA from ACB complex and other Acinetobacter species. These assays were then applied to detect VAT genes in cultured ACB complex isolates recovered from clinical and environmental sources. Widespread detection of VAT genes in environmental isolates confirmed the validity, functionality, and applicability of these novel assays. Overall, the three newly developed ACB complex species-specific mPCR assays are rapid and simple tools that can be adopted in diagnostic and clinical lab settings. The detection of VAT genes in environmental isolates suggests that environmental niches could serve as a reservoir for potentially pathogenic ACB complex and warrants further investigation. The newly developed mPCR assays are specific, sensitive, and efficient, making them well-suited for high-throughput screening in epidemiological studies and evaluating the potential pathogenicity of ACB complex recovered from various sources.

Detection and full genomic sequencing of rare hepatitis E virus genotype 4d in Italian wastewater, undetected by clinical surveillance

Hepatitis E is a liver disease caused by the hepatitis E virus (HEV), primarily transmitted through contaminated water or food. There are four different HEV genotypes in humans, with genotypes 1 and 2 being the most widespread. Genotypes 3 and 4 are found in animals and can also infect humans. Genotype 4 is prevalent in Asia, mainly in China. In Italy, only one outbreak of HEV-4 has been documented, which occurred in 2011, involving five patients. In 2013, HEV G4 was also detected in a pig farm. Since then, no further evidence of HEV genotype 4 has been found in the country. This study describes the first detection of HEV genotype 4, subtype d, in wastewater in central Italy, despite a lack of any clinical case reported in the area. By using a multiplex PCR protocol and two sequencing strategies, Illumina and ONT, the virus's complete genome was sequenced and characterized as subtype 4d. These findings shed light on the potential of environmental surveillance for infectious agents to improve our understanding of epidemiology and support public health efforts.

Development and Validation of a TaqMan Multiplex Real-Time PCR Assay for High-Throughput Quantification of Fusarium graminearum Biomass in Barley Spikes and Grains

Fusarium head blight (FHB) is a devastating disease primarily caused by Fusarium graminearum that commonly affects North American small grains. Although the disease causes visible symptoms, the more pressing concern is the contamination of grain with trichothecene toxins, especially deoxynivalenol (DON), which can cause toxicity in humans and animals by inhibiting protein biosynthesis. The DON levels are more critical when breeding for resistance, but this does not account for pathogen infection and disease severity. To link DON and Fusarium infection, we optimized and validated a real-time multiplex quantitative PCR protocol for high-throughput quantification of Fusarium biomass based on the Tri5 gene, which encodes trichodiene synthase, the first enzyme involved in trichothecene toxin production. The primers and probes were designed to measure the abundance of Tri5 and normalized to the barley actin gene. The assay is repeatable, robust, and sensitive, up to 0.003 ng/µl of F. graminearum and 0.3 ng/µl of barley DNA. The method is cost-effective and has the potential to quantify Fusarium biomass, monitor disease progression, and determine DON levels in barley spikes and harvested grains. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Characterization of DoTc2 4510-Identifying HPV16 Presence in a Cervical Carcinoma Cell Line Previously Considered to Be HPV-Negative.

Cervical cancer is the fourth leading cause of cancer deaths in women, with over 340,000 women dying from this disease in 2020. Almost all cases have an underlying persistent infection with an oncogenic high-risk type of human papillomavirus (HPV), mainly HPV16. While cervical squamous cell carcinoma is hardly ever HPV-negative, a small subset of adenocarcinoma exhibits absence of HPV, even after disproval of false-negative testing results due to low viral load. This proportion is evident in many cervical cancer studies and is reflected in the repertoire of model cell lines commonly used in research. As the viral origin of cervical cancer makes it a disease preventable and potentially treatable by immunotherapeutic approaches, it is the focus of many studies. For pertinent research, both a broad set of HPV-infected cervical carcinoma models are required, as well as stringent negative controls. A ubiquitously used HPV-negative cervical adenocarcinoma cell line is C-33A. Another cervical cancer cell line is available for purchase from the American Type Culture Collection (ATCC), namely DoTc2 4510, described to be HPV-negative and thus as a model for a rare gynecological malignancy. Here, we present findings proving that DoTc2 4510 is, in fact, an HPV16-positive cell line. This we assessed using a highly sensitive nested multiplex PCR protocol adapted for the identification of 12 carcinogenic HPV types and a second PCR targeting the HPV16 oncogenes E6 and E7. Subsequently, the protein expression of E6 and E7 was examined, as well as the expression of their target proteins p53, p21, and p16INK4a, to assess E6/E7 functionality. Finally, to attest to the survival dependence of DoTc2 4510 cells on HPV16, we performed an HPV16 E6/E7-targeted siRNA knock-down, which indeed led to senescence induction. Together, these findings demonstrate that DoTc2 4510 is an HPV16-transformed cell line.

Multiplex touchdown Polymerase Chain Reaction for rapid detection of Salmonella enterica subsp. enterica serovars Enteritidis and Typhimurium in food

The Salmonella outbreak is one of the leading foodborne diseases in the world with increasing cases being reported annually. However, the current methods for Salmonella detection in foods are outdated, laborious and time-consuming. This necessitated developing a technique that is rapid for Salmonella detection in foods. Thus, the current study aimed to develop a multiplex touchdown PCR (m-TdPCR) protocol for rapid and simultaneous detection of Salmonella enterica subsp. enterica serovars Enteritidis and Typhimurium in foods. A two-phase m-TdPCR protocol was developed and optimized with primer pairs targeting the Salmonella enterica subsp. enterica (ST11/ST15-0.15 µM), serovars Enteritidis (sdfI gene-1.2 µM), Typhimurium (fliC gene-1.5 µM) and an internal amplification control (16S rRNA-0.08 µM). It was found that the m-TdPCR protocol is highly sensitive detecting up to 1 ng of Salmonella DNA and its specificity was verified using the in-silico method. Furthermore, the developed m-TdPCR shows no non-specific PCR amplicons and is able to detect both S. enterica ser. Enteritidis and S. enterica ser. Typhimurium in real-time when tested against the artificially contaminated food samples at up to 10-3 dilutions. Therefore, the validated m-TdPCR protocol in this study can be used as a tool for rapid detection of S. enterica ser. Enteritidis and S. enterica ser. Typhimurium in food samples and this may significantly reduce any related foodborne incidences in future.

Development of TaqMan Real-Time PCR Protocols for Simultaneous Detection and Quantification of the Bacterial Pathogen Ralstonia solanacearum and Their Specific Lytic Bacteriophages.

Ralstonia solanacearum is the causal agent of bacterial wilt, one of the most destructive diseases of solanaceous plants, affecting staple crops worldwide. The bacterium survives in water, soil, and other reservoirs, and is difficult to control. In this sense, the use of three specific lytic R. solanacearum bacteriophages was recently patented for bacterial wilt biocontrol in environmental water and in plants. To optimize their applications, the phages and the bacterium need to be accurately monitored and quantified, which is laborious and time-consuming with biological methods. In this work, primers and TaqMan probes were designed, and duplex and multiplex real-time quantitative PCR (qPCR) protocols were developed and optimized for the simultaneous quantification of R. solanacearum and their phages. The quantification range was established from 108 to 10 PFU/mL for the phages and from 108 to 102 CFU/mL for R. solanacearum. Additionally, the multiplex qPCR protocol was validated for the detection and quantification of the phages with a limit ranging from 102 targets/mL in water and plant extracts to 103 targets/g in soil, and the target bacterium with a limit ranging from 103 targets/mL in water and plant extracts to 104 targets/g in soil, using direct methods of sample preparation.

Response Surface Methodology for Optimization of Multiplex-PCR Protocols for Detection of TYLCV, TSWV and Fol Molecular Markers: Analytical Performance Evaluation.

Molecular markers linked to disease resistance genes which affect economically important crops are of great interest. In the case of tomato, a major focus on resistance breeding to multiple fungal and viral pathogens such as Tomato yellow leaf curl virus (TYLCV), Tomato spotted wilt virus (TSWV) and Fusarium oxysporum f. sp. lycopersici (Fol), have led to the introgression of several resistance genes; therefore, molecular markers have become important in molecular-assisted selection (MAS) of tomato varieties resistant to those pathogens. However, assays that allow simultaneous evaluation of resistant genotypes, such as multiplex PCR, need to be optimized and evaluated to demonstrate their analytical performance, as many factors can affect them. This work aimed to generate multiplex PCR protocols for the joint detection of the molecular markers associated with pathogen resistance genes in tomato plants that are sensitive, specific and repeatable. For the optimization a central composite design of a response surface methodology (RSM-CCD) was used. For analytical performance evaluation, specificity/selectivity and sensibility (limit of detection and dynamic range) were analyzed. Two protocols were optimized: the first one with a desirability of 1.00, contained two markers (At-2 and P7-43) linked to I- and I-3-resistant genes. The second one with a desirability of 0.99, contained markers (SSR-67, SW5 and P6-25) linked to I-, Sw-5-, and Ty-3-resistant genes. For protocol 1, all the commercial hybrids (7/7) were resistant to Fol, and for protocol 2, two hybrids were resistant to Fol, one to TSWV and one to TYLCV with good analytical performance. In both protocols, the varieties considered susceptible to the pathogens, no-amplicon or susceptible amplicons, were observed. The optimized multiplex PCR protocols showed dynamic ranges from 5.97 up to 161.3 ng DNA. The limit of detection was 17.92 ng and 53.76 ng DNA for protocols 1 and 2, respectively, giving 100% positive results in the test replicates. This method allowed to develop optimized multiplex PCR protocols with few assays which translates into less time and resources, without sacrificing method performance.

Multiplex PCR assay for the simultaneous identification of race specific and non-specific leaf resistance genes in wheat (Triticum aestivum L.)

Race-nonspecific resistance is a key to sustainable management of pathogens in bread wheat (Triticum aestivum L.) breeding. It is more durable compared to race-specific immunity, conferred by the major genes (R), which are often overcome by pathogens. The accumulation of the genes, which provide the resistance to a specific race of a pathogen, together with the introduction of race-non-specific resistance genes is the most effective strategy aimed at preventing the breakdown of genetically conditioned immunity. PCR markers improved the productivity and accuracy of classical plant breeding by means of marker-assisted selection (MAS). Multiplexing assays provide increased throughput, reduced reaction cost, and conservation of limited sample material, which are beneficial for breeding purposes. Here, we described the process of customizing multiplex PCR assay for the simultaneous identification of the major leaf rust resistance genes Lr19, Lr24, Lr26, and Lr38, as well as the slow rusting, race-nonspecific resistance genes: Lr34 and Lr68, in thirteen combinations. The adaptation of PCR markers for multiplex assays relied on: (1) selection of primers with an appropriate length; (2) selection of common annealing/extension temperature for given primers; and (3) PCR mixture modifications consisting of increased concentration of primers for the scanty band signals or decreased concentration of primers for the strong bands. These multiplex PCR protocols can be integrated into a marker-assisted selection of the leaf rust-resistant wheat genotypes.

Pre-implantation genetic testing for Marfan syndrome using mini-sequencing

Marfan syndrome (MFS1) is an autosomal dominant condition causing aortopathy including fatal aortic dissection. This study aimed to perform clinical PGT-M in a family with a history of MFS1 for two generations. A family with two members affected by MFS1 approached the hospital for PGT-M. The couple decided to join the project following extensive counselling and informed consent was obtained. The mutation contributory to MFS1 was identified using whole-exome sequencing (WES). A novel PGT-M protocol using multiplex fluorescent PCR and mini-sequencing was developed and tested. Ten blastocysts were subjected to PGT-M in two clinical PGT cycles. Mini-sequencing revealed four normal and six affected embryos. Microsatellite-based linkage analysis confirmed mutation analysis results in all samples. The embryos diagnosed as normal (non-MFS1) were chosen for transfer. A pregnancy was obtained in the third embryo transfer. Invasive prenatal diagnosis confirmed the normal genotype of the baby. This study demonstrated comprehensive management using the application of clinical-based diagnosis, WES for mutation identification within the MFS1 gene, mini-sequencing for embryo selection and microsatellite-based linkage analysis for backup of PGT-M results and contamination detection to assist couples in having a healthy child when there was a family history of Marfan syndrome. Impact Statement What is already known on this subject? Marfan syndrome (MFS1, OMIM#154700) is an autosomal dominant condition causing aortopathy including fatal aortic dissection. Pre-implantation genetic testing (PGT) is an alternative to traditional invasive prenatal diagnosis (PND) giving the couples the chance of starting pregnancy with the confidence that the baby will be unaffected. Most of the previous PGT reports employed microsatellite-based linkage analysis. A few PGT studies used sequencing, mini-sequencing and mutation analysis; however, the details of the techniques were not described. What do the results of this study add? Single-cell PCR protocol using multiplex fluorescent PCR and mini-sequencing was developed and validated. Two clinical PGTs cycles for Marfan syndrome were performed. A healthy baby was resulted. The details of multiplex fluorescent PCR and mini-sequencing protocols are described in this study so that the procedures can be reproduced. What are the implications of these findings for clinical practice and/or further research? Embryo selection can help the family suffering from Marfan syndrome for two generations to start a pregnancy with confidence that their child will be unaffected. This study also shows the use of a mini-sequencing protocol for PGT, which can be a universal protocol for other mutations by changing the PCR primers and mini-sequencing primers.

Prevalence of extended spectrum Beta-Lactamase producing Klebsiella species from patients' specimens in a tertiary teaching hospital in Ile-Ife, Southwest Nigeria.

This study determined the prevalence of ESBL genes amongst Klebsiella species isolated from patients' specimens attending a Tertiary Teaching Hospital, in Ile-Ife, Southwest Nigeria. A cross sectional study of presumptive isolates of Klebsiella (n=180) were collected, after ethical approval in the microbiology laboratory. Isolates were identified to species level by conventional biochemical tests and MicrobactTM 24E Identification Kits. Antibiotic susceptibility testing was performed by the Kirby Bauer's disk diffusion method. ESBL production was detected by the double disc synergy and ESBL genes by the multiplex PCR protocol. The Klebsiella species identified were Klebsiella pneumoniae 95.6%, Klebsiella oxytoca 3.3%, Klebsiella ornithinolytica 0.6% and Klebsiella terrigena 0.6%. The prevalence of ESBL genes among the Klebsiella isolates was 47.2%, and the most common ESBL gene was blaSHV (38.9%), also 75% of the study isolates had MAR index greater than 0.2. The study establishes the prevalence of Extended Spectrum Beta-Lactamase producing Klebsiella sp in the hospital and identified the most prevalent ESBL genes circulating as blaSHV followed by blaTEM and blaCTX-M in this environment. This underscores the need for regular and continuous surveillance of antimicrobial resistance trend as a strong component of the antibiotics stewardship and infection prevention and control programs in the hospital.

A novel one-step multiplex PCR protocol to detect avian haemosporidian parasites in the subgenus Haemoproteus (Kruse, 1890) used to quantify parasite prevalence in domestic pigeons (Columba livia) in Turkey.

Infections of avian haemosporidian parasites are regularly identified by molecular methods including multiplex PCR, which allows researchers to distinguish mixed infections of parasites from multiple genera. Here we extend the utility of a previously designed multiplex PCR by designing a primer set specific to parasites of the subgenus Haemoproteus (genus: Haemoproteus). The updated one-step multiplex PCR protocol we describe here allows for the detection of the genera Plasmodium and Leucocytozoon and the two subgenera (Haemoproteus and Parahaemoproteus) of the genus Haemoproteus. A sensitivity analysis showed that the multiplex PCR could amplify DNA of parasites in the subgenus Haemoproteus at very low levels of infection. We used this multiplex PCR to identify haemosporidian infections in 250 adult domestic pigeons (Columba livia) in Turkey. All samples were also screened by microscopy and a widely used nested PCR to compare with the results of multiplex PCR, to detect low levels of parasitemia, and to identify possible abortive infections. In total, 71 pigeons (28.4%) were found to be infected by all three methods. The multiplex PCR protocol successfully detected and discriminated both subgenera Haemoproteus and Parahaemoproteus infections. We compared our results with previous host species records to assess the host specificity of the parasite lineages we found. Our findings provide novel data on the prevalence of avian haemosporidians in domestic pigeons and demonstrate the utility of the new one-step multiplex PCR protocol for the determination of mixed avian haemosporidian infections. We expect that this protocol will contribute to a better understanding of the distribution, epizootiology, and ecology of avian haemosporidians.

Development of Multiplex PCR-based Protocols for Simultaneous Caterpillar Diagnosis of Three Spodoptera and One Mamestra Species (Lepidoptera: Noctuidae).

Since many noctuid moth species are highly destructive crop pests, it is essential to establish proper management strategies, which primarily require accurate and rapid species identification. However, diagnosis of noctuid species in the field, particularly at the larval stage, is very difficult due to their morphological similarity and individual color variation. In particular, caterpillars of Spodoptera exigua (Hübner), Spodoptera litura (Fabricius), Spodoptera frugiperda (Smith), and Mamestra brassicae (L.) (Lepidoptera: Noctuidae) are hard to be identified by morphology and frequently found on the same host crops in the same season, thus requiring a reliable species diagnosis method. To efficiently diagnose these species, we identified species-specific internal transcribed spacer 1 (ITS1) sequences and developed two molecular species diagnosis protocols using ITS1 markers. The first protocol was multiplex conventional PCR in conjunction with subsequent gel electrophoresis for species identification based on amplicon size. The second protocol was based on multiplex real-time PCR using fluorescent dye-labeled primers for single-step diagnosis. Template genomic DNA (gDNA) prepared by the DNA release method was also suitable for both protocols as the template prepared by DNA extraction. The two protocols enabled rapid and robust species diagnosis using a single multiplex PCR step. Depending on laboratory instrumentation, one of the two protocols can be easily adapted for species diagnosis of the four noctuid caterpillars in the field, which is essential for establishing proper management strategies. The multiplex real-time PCR protocol, in particular, will facilitate accurate diagnosis of the four species in a single step regardless of template gDNA quality.

Development of multiplex PCR assay for detection of Alternaria brassicae, A. brassicicola and Xanthomonas campestris pv. campestris in crucifers.

Among biotic stresses, Alternaria leaf spots caused by Alternaria brassicae and A. brassicicola and black rot caused by Xanthomonas campestris pv. campestris are major limiting factors in brassica cultivation across the world. Because of seed-borne nature of these pathogens primarily, disease-free conservation as well as exchange of brassica seeds at domestic as well as international level are major challenges. To facilitate disease-free conservation and transboundary movement of brassica germplasm, a highly specific and sensitive method was developed for simultaneous detection of these pathogens. A set of primers namely, AbeABC1F and AbeABC1R based on ABC transporter (Atr1) gene for A. brassicae, Aba28sF and Aba28sR based on SSR marker was developed for A. brassicicola as well as rpf gene-based primers namely, rpfH_F and rpfH_R for X. campestris pv. campestris were used for multiplex PCR. The specific bands of 586, 201 and 304bp were obtained in multiplex PCR assay for A. brassicae, A. brassicicola and X. campestris pv. campestris, respectively. Therefore, the developed multiplex PCR protocol could be utilized for a reliable diagnosis of these pathogens to facilitate safe conservation, exchange of seeds to the researchers and also by seed certification agencies for ensuring quality seed availability to farmers.