Burkholderia pseudomallei
causes a fatal and infectious disease, melioidosis or Whitmore’s disease in humans and animals. Melioidosis is present in different parts of the world and is endemic in ...Southeast Asia and Northern Australia. Accurate diagnosis of melioidosis is difficult due to its common flu-like symptoms, potentially long incubation period and erroneous identification as culture contaminant. Early diagnosis of the disease is essentially required for administration of suitable antibiotics and disease containment. The present study reports a rapid, specific and sensitive recombinase polymerase amplification lateral flow assay for detection of
B. pseudomallei.
Specific primers and probe were designed and the assay was performed at 41 °C for 20 min in a portable incubator. End products were detected using ready-to-use lateral flow strips. RPA lateral flow assay could detect ≥ 250 fg genomic DNA of
B. pseudomallei
and ≥ 50 copies of recombinant plasmid harbouring the target DNA sequence. The assay was found to be highly specific and did not cross-react with other bacterial strains. In artificially spiked human blood and urine samples, the detection limit of the assay was 4.8 × 10
4
and 4.95 × 10
4
CFU/mL of
B. pseudomallei
, respectively. The detection limit of assay after 6 h of enrichment of artificially spiked urine samples was found to be 4.95 × 10
3
CFU/mL of
B. pseudomallei
. Detection limit in artificially spiked tap water and soil samples was determined to be 7.5 × 10
2
CFU/mL and 3.3 × 10
4
CFU per 5 g of
B. pseudomallei
, respectively.
Bacillus anthracis
, the causative agent of anthrax is one of the most potent listed biological warfare agents. The conventional microbiological methods of its detection are labor intensive and time ...consuming, whereas molecular assays are fast, sensitive and specific. PCR is one of the most reliable diagnostic tools in molecular biology. The combination of PCR with lateral flow strips can reduce the diagnostic/detection time. It gives an alternative to gel electrophoresis and offers easy and clear interpretation of results. In the present study, a PCR Lateral flow (PCR-LF) assay targeting
cya
gene present on pXO1 plasmid of
B. anthracis
has been developed. The forward and reverse primers were tagged with 6-carboxyflourescein (6-FAM) and biotin, respectively, at 5′ end. The dual labeled PCR products were detected using lateral flow (LF) strips developed in this study. The PCR-LF assay could detect ≥ 5 pg of genomic DNA and ≥ 500 copies of target DNA harboured in a recombinant plasmid. The assay was able to detect as few as 10
3
and 10 CFU/mL of
B. anthracis
Sterne cells spiked in human blood after 6 and 24 h of enrichment
,
respectively.
Bacillus anthracis
, the causative agent of anthrax is a Gram-positive, non-motile, spore forming bacterium. Its spores can persist in soil and water for years and can also be aerosolized. A rapid, ...sensitive and specific method to detect
B. anthracis
is important for clinical management and preventing spread of anthrax. Loop-mediated isothermal amplification (LAMP) assay is a rapid technique that amplifies target DNA in isothermal conditions with high sensitivity and specificity. In this study, a LAMP assay set targeting a chromosomal and two plasmid markers was developed. The individual assays of the LAMP set targeting pXO1 plasmid (
lef
), pXO2 plasmid (
capB
), and chromosome (
BA5345
) sequences could detect 10, 250, and 100 fg of genomic DNA and 10, 100, and 50 copies of the DNA targets harboured in recombinant plasmids, respectively. The
lef
and
capB
LAMP assays could detect ≥ 1 × 10
3
CFU per mL of bacteria in spiked human blood samples, while
BA5345
LAMP assay could detect ≥ 1 × 10
4
CFU of bacteria per mL of spiked blood. The amplification was monitored in real-time by turbidimeter, and visual detection was also accomplished under normal and UV light after adding SYBR Green 1 dye on completion of the reaction. The assay set was found to be highly sensitive and did not cross-react with the closely related
Bacillus
spp. and other bacterial strains used in the study.
The consequences of climate change are drastically impacting field crop production; it is an immense prerequisite to attribute resilience through crop improvement. Thus, the breeders' task is to ...sustain yield potential in changing climate, which imperils the food grain security. Globally, high temperature is one of the grounds that support climate change. High temperature critically affects the sensitive stages of rice, starting from anthesis to grain filling, which dictates plant reproduction. In tropical conditions, it is often the yield-limiting factor and sources for yield penalty with poor grain quality. Exploring the ways to mitigate heat tolerance in rice resulted in identifying key traits like early morning flowering, pollen fertility, pollen shedding percentage, stigma receptivity, and spikelet fertility. Identifying germplasm resources with heat-tolerance traits is the foremost task followed by exploiting them in climate-resilient rice breeding. It prompts the breeding practices to improve tolerant varieties as an adaptation option suggested by various simulated crop models. With the advances in biotechnology, there are still more comprehensions required in connection to genetics, physiology, and molecular responses of heat tolerance. Herein, we reviewed the consequence of heat tolerance, germplasm resources, genetic and genomic mechanisms for attenuating heat stress impact of rice.
Rice (Oryza sativa) being among the most important food crops in the world is also susceptible to various bacterial and fungal diseases that are the major stumbling blocks in the way of increased ...production and productivity. The bacterial leaf blight caused by Xanthomonas oryzae pv. oryzae and the sheath blight disease caused by Rhizoctonia solani are among the most devastating diseases of the rice crop. In spite of the availability of array of chemical control, there are chances of development of resistance. Thus, there is a need for the nanotechnological intervention for management of disease in the form of copper and silver nano-composites. The copper (CuNPs) and silver nanoparticles (AgNPs) were synthesized using green route and characterized using different high throughput techniques, i.e., UV-Vis, FT-IR, DLS, XRD, FE-SEM, TEM. The particle size and zeta potential of synthesized CuNPs and AgNPs were found 273 nm and - 24.2 mV; 95.19 nm and - 25.5 mV respectively. The nanocomposite of CuNPs and AgNPs were prepared having particle size in the range of 375-306 nm with improved stability (zeta potential - 54.7 to - 39.4 mV). The copper and silver nanoparticle composites evaluated against Xanthomonas oryzae pv. oryzae and Rhizoctonia solani were found to have higher antibacterial (inhibition zone 13 mm) and antifungal activities (77%) compared to only the copper nanoparticle (8 mm; 62% respectively). Net house trials of nano-composite formulations against the bacterial blight of rice also corroborated the potential of nanocomposite formulation. In silico studies were carried out selecting two disease-causing proteins, peptide deformylase (Xanthomonas oryzae) and pectate lyase (Rhizoctonia solani) to perform the molecular docking. Interaction studies indicatedthat both of these proteins generated better complex with CuNPs than AgNPs. The study suggested that the copper and silver nano-composites could be used for developing formulations to control these devastating rice diseases.
Reeta is a popular late-maturing high-yielding rice variety recommended for cultivation in the eastern Indian states. The cultivar is highly sensitive to submergence stress. Phosphorus deficiency is ...an additional constraint for realizing high yield. The quantitative trait loci (QTLs),
, for submergence and
for low phosphorus stress tolerance along with narrow-grained trait,
were introgressed into the variety from the donor parent, Swarna-Sub1 through marker-assisted breeding. In addition, phenotypic selections for higher panicle weight, grain number, and spikelet fertility were performed in each segregating generation. Foreground selection detected the 3 target QTLs in 9, 8 and 7 progenies in the BC
F
, BC
F
, and BC
F
generation, respectively. Recurrent parent's genome recovery was analyzed using 168 SSR polymorphic markers. The foreground analysis in 452 BC
F
progenies showed five pyramided lines in homozygous condition for the target QTLs. No donor fragment drag was noticed in the
and
QTLs carrier while a segmentwas observed in the
carrier chromosome. The developed lines were higher yielding, had submergence, and had low phosphorus stress-tolerance alongwith similar to the recipient parent in the studied morpho-quality traits. A promising pyramided line is released in the name of Reeta-Panidhan (CR Dhan 413) for the flood-prone areas of Odisha state.
The majority of Gladiolus plants growing in the botanical garden at NBRI, Lucknow, India and adjoining areas exhibited symptoms of mosaic, color breaking, stunting of spikes and reduction in flower ...size. The occurrence of Cucumber mosaic virus (CMV) was suspected in symptomatic Gladiolus plants. Cucumber mosaic virus, the type species of the genus Cucumovirus of the family Bromoviridae, is an important plant virus worldwide, which infects many plants and causes quantity and quality losses. For virus characterization, total RNA was isolated from leaves of infected plants and used in reverse transcriptase polymerase chain reaction with a primer set designed in the Cucumber mosaic virus coat protein region. Viral amplicons of the expected 657 bp size were obtained from infected plants. No viral amplicon was obtained from healthy control plants. Viral amplicons were cloned and sequenced (DQ295914). Molecular characterization was performed and phylogenetic relationship determined by the comparison of coat protein gene nucleotide and amino acid sequences with other Cucumber mosaic virus isolates reported from India and worldwide. The nucleotide and amino acid percentage comparison and phylogenetic tree results revealed that Cucumber mosaic virus infecting Gladiolus show resemblance with the Fny strain, which is not common in the Asian continent.
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