7 research outputs found
Not Available
Not AvailableIndia is endemic for foot-and-mouth disease (FMD) and in recent years a unique group within serotype A, carrying a codon deletion at an antigenically critical site in capsid protein VP3 has emerged (VP3(59)-deletion group). This tempted us to analyze the noncoding region, which is an under represented area, though critically associated with virus biology and pathogenesis. Analysis of the large fragment of 5' untranslated region (LF-5' UTR) of type A FMD virus revealed discrepancy in the overall tree topology between LF-5' UTR and 1D region possibly due to independent evolution of coding and noncoding regions. The VP3(59)-deletion group maintained its phylogenetic distinctness even at the LF-5' UTR. Eighteen lineage specific signatures detected here support independent evolutionary paths for the lineages. Extensive deletions of 45 and 89 nucleotides corresponding to the pseudoknot region were noticed. Conservation pattern in the 'A(253)AACA' motif in the cre/bus stem-loop indicates the importance of first three 'A' residues in VPg uridylylation. Of the three polypyrimidine tract binding protein (PTB) binding sites mapped on the internal ribosome entry site (IRES), the pyrimidine tract (Py tract) in the loop of domain 2 was found to be maximally conserved and it might be the major PTB binding site. Strikingly, a deletion group lineage specific transversion was noticed in the Py tract at the 3' end of IRES without significantly affecting its in vitro infectious titer. Hence, we presume that for efficient cap-independent viral translation, either a minimum number of pyrimidine residues rather than a complete Py tract or a Py tract tolerating transversions only at specific locations and a core motif 'CUUU' within the Py tract is essential.Not Availabl
Development, standardization and validation of molecular techniques for malaria vector species identification, trophic preferences, and detection of Plasmodium falciparum
Background & objectives: Knowledge on prevalence of malaria vector species of a certain area provides important information for implementation of appropriate control strategies. The present study describes a rapid method for screening of major Anopheline vector species and at the same time detection of Plasmodium falciparum sporozoite infection and blood meal preferences/trophic preferences.
Methods: The study was carried from February 2012 to March 2013 in three seasons, i.e. rainy, winter and summer in Jhumpura PHC of Keonjhar district, Odisha, India. Processing of mosquitoes was carried out in two different methods, viz. mosquito pool (P1) and mosquito DNA pool (P2). Pool size for both the methods was standardized for DNA isolation and multiplex PCR assay. This PCR based assay was employed to screen the major vector composition in three different seasons of four different ecotypes of Keonjhar district. Pearson’s correlation coefficient was determined for a comparative analysis of the morphological identification with the pool prevalence assay for each ecotype.
Results: A pool size of 10 was standardized for DNA isolation as well as PCR. PCR assay revealed that the average pool prevalence for all ecotypes was highest for An. annularis in winter and summer whereas for An. culicifacies it was rainy season. Foothill and plain ecotypes contributed to highest and lowest vectorial abundance respectively. The results of the prevalence of vector species in pool from PCR based assay were found to be highly correlated with that of the results of morphological identification.
Interpretation & conclusion: Screening by pool based PCR assay is relatively rapid as compared to conventional morphological identification and can be employed as an important tool in malaria control programmes
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Not AvailableIn India, there has been co-circulation, extinction and emergence of genotypes/lineages within serotype A foot-and-mouth disease (FMD) virus. At present an antigenically heterogeneous, unique lineage within genotype VII dominates the field outbreaks. This genetic cluster has amino acid deletion at position 59 of VP3 (VP359-deletion group), considered to be critical antigenically. The emergence of this group warrants rapid and accurate detection to facilitate early planning and implementation of an effective control policy. A rapid multiplex PCR assay was developed for detection of the dominating VP359-deletion group with 100% sensitivity and specificity, even before generating sequence data and confirmatory phylogenetic analysis. This development is important for surveillance of FMD in India.Not Availabl
Molecular Breeding for Incorporation of Submergence Tolerance and Durable Bacterial Blight Resistance into the Popular Rice Variety ‘Ranidhan’
Ranidhan is a popular late-maturing rice variety of Odisha state, India. The farmers of the state suffer heavy loss in years with flash floods as the variety is sensitive to submergence. Bacterial blight (BB) disease is a major yield-limiting factor, and the variety is susceptible to the disease. BB resistance genes Xa21, xa13, and xa5, along with the Sub1 QTL, for submergence stress tolerance were transferred into the variety using marker-assisted backcross breeding approach. Foreground selection using direct and closely linked markers detected the progenies carrying all four target genes in the BC1F1, BC2F1, and BC3F1 generations, and the positive progenies carrying these genes with maximum similarity to the recipient parent, Ranidhan, were backcrossed into each segregating generation. Foreground selection in the BC1F1 generation progenies detected all target genes in 11 progenies. The progeny carrying all target genes and similar to the recipient parent in terms of phenotype was backcrossed, and a total of 321 BC2F1 seeds were produced. Ten progenies carried all target genes/QTL in the BC2F1 generation. Screening of the BC3F1 progenies using markers detected 12 plants carrying the target genes. A total of 1270 BC3F2 seeds were obtained from the best BC3F1 progeny. Foreground selection in the BC3F2 progenies detected four plants carrying the target genes in the homozygous condition. The bioassay of the pyramided lines conferred very high levels of resistance to the predominant isolates of bacterial blight pathogen. These BB pyramided lines were submergence-tolerant and similar to Ranidhan in 13 agro-morphologic and grain quality traits; hence, they are likely to be adopted by farmers
Not Available
Not AvailableRanidhan is a popular late-maturing rice variety of Odisha state, India. The farmers of the
state suffer heavy loss in years with flash floods as the variety is sensitive to submergence. Bacterial
blight (BB) disease is a major yield-limiting factor, and the variety is susceptible to the disease. BB
resistance genesXa21, xa13, and xa5, along with the Sub1 QTL, for submergence stress tolerance
were transferred into the variety using marker-assisted backcross breeding approach. Foreground
selection using direct and closely linked markers detected the progenies carrying all four target
genes in the BC1F1, BC2F1, and BC3F1 generations, and the positive progenies carrying these genes
with maximum similarity to the recipient parent, Ranidhan, were backcrossed into each segregating
generation. Foreground selection in the BC1F1 generation progenies detected all target genes in 11
progenies. The progeny carrying all target genes and similar to the recipient parent in terms of
phenotype was backcrossed, and a total of 321 BC2F1 seeds were produced. Ten progenies carried
all target genes/QTL in the BC2F1 generation. Screening of the BC3F1 progenies using markers
detected 12 plants carrying the target genes. A total of 1270 BC3F2 seeds were obtained from the best
BC3F1 progeny. Foreground selection in the BC3F2 progenies detected four plants carrying the target
genes in the homozygous condition. The bioassay of the pyramided lines conferred very high levels
of resistance to the predominant isolates of bacterial blight pathogen. These BB pyramided lines
were submergence-tolerant and similar to Ranidhan in 13 agro-morphologic and grain quality
traits; hence, they are likely to be adopted by farmers.Not Availabl
Molecular Breeding for Incorporation of Submergence Tolerance and Durable Bacterial Blight Resistance into the Popular Rice Variety ‘Ranidhan’
Ranidhan is a popular late-maturing rice variety of Odisha state, India. The farmers of the state suffer heavy loss in years with flash floods as the variety is sensitive to submergence. Bacterial blight (BB) disease is a major yield-limiting factor, and the variety is susceptible to the disease. BB resistance genes Xa21, xa13, and xa5, along with the Sub1 QTL, for submergence stress tolerance were transferred into the variety using marker-assisted backcross breeding approach. Foreground selection using direct and closely linked markers detected the progenies carrying all four target genes in the BC1F1, BC2F1, and BC3F1 generations, and the positive progenies carrying these genes with maximum similarity to the recipient parent, Ranidhan, were backcrossed into each segregating generation. Foreground selection in the BC1F1 generation progenies detected all target genes in 11 progenies. The progeny carrying all target genes and similar to the recipient parent in terms of phenotype was backcrossed, and a total of 321 BC2F1 seeds were produced. Ten progenies carried all target genes/QTL in the BC2F1 generation. Screening of the BC3F1 progenies using markers detected 12 plants carrying the target genes. A total of 1270 BC3F2 seeds were obtained from the best BC3F1 progeny. Foreground selection in the BC3F2 progenies detected four plants carrying the target genes in the homozygous condition. The bioassay of the pyramided lines conferred very high levels of resistance to the predominant isolates of bacterial blight pathogen. These BB pyramided lines were submergence-tolerant and similar to Ranidhan in 13 agro-morphologic and grain quality traits; hence, they are likely to be adopted by farmers