Dr. Ajay Kumar Mahato

Dr. Dr. Ajay Kumar Mahato

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 May 2020 in Scientific Reports
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Journal Article
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ASAnuradha Singh
Anuradha Singh
YSYashi Singh
Yashi Singh
DMDr. Ajay Kumar Mahato
Dr. Ajay Kumar Mahato
PJPawan K. Jayaswal
Pawan K. Jayaswal
SSSangeeta Singh
Sangeeta Singh
VRVandna Rai
Vandna Rai
Erratic rainfall leading to flash flooding causes huge yield losses in lowland rice. The traditional varieties and landraces of rice possess variable levels of tolerance to submergence stress, but gene discovery and utilization of these resources has been limited to the Sub1A-1 allele from variety FR13A. Therefore, we analysed the allelic sequence variation in three Sub1 genes in a panel of 179 rice genotypes and its association with submergence tolerance. Population structure and diversity analysis based on a 36-plex genome wide genic-SNP assay grouped these genotypes into two major categories representing Indica and Japonica cultivar groups with further sub-groupings into Indica, Aus, Deepwater and Aromatic-Japonica cultivars. Targetted re-sequencing of the Sub1A, Sub1B and Sub1C genes identfied 7, 7 and 38 SNPs making 8, 9 and 67 SNP haplotypes, respectively. Haplotype networks and phylogenic analysis revealed evolution of Sub1B and Sub1A genes by tandem duplication and divergence of the ancestral Sub1C gene in that order. The alleles of Sub1 genes in tolerant reference variety FR13A seem to have evolved most recently. However, no consistent association could be found between the Sub1 allelic variation and submergence tolerance probably due to low minor allele frequencies and presence of exceptions to the known Sub1A-1 association in the genotype panel. We identified 18 cultivars with non-Sub1A-1 source of submergence tolerance which after further mapping and validation in bi-parental populations will be useful for development of superior flood tolerant rice cultivars.

18 March 2020 in Scientific Reports
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SSSangeeta Singh
Sangeeta Singh
DMDr. Ajay Kumar Mahato
Dr. Ajay Kumar Mahato
PJPawan K. Jayaswal
Pawan K. Jayaswal
NSNisha Singh
Nisha Singh
MDMeenakshi Dheer
Meenakshi Dheer
Nagendra Kumar SinghNagendra Kumar Singh
Nagendra Kumar Singh
Pigeonpea is the second most important pulse legume crop for food and nutritional security of South Asia that requires accelerated breeding using high throughput genomic tools. Single nucleotide polymorphisms (SNPs) are highly suitable markers for this purpose because of their bi-allelic nature, reproducibility and high abundance in the genome. Here we report on development and use of a pigeonpea 62 K SNP chip array ‘CcSNPnks’ for Affymetrix GeneTitan® platform. The array was designed after filtering 645,662 genic-SNPs identified by re-sequencing of 45 diverse genotypes and has 62,053 SNPs from 9629 genes belonging to five different categories, including 4314 single-copy genes unique to pigeonpea, 4328 single-copy genes conserved between soybean and pigeonpea, 156 homologs of agronomically important cloned genes, 746 disease resistance and defense response genes and 85 multi-copy genes of pigeonpea. This fully genic chip has 28.94% exonic, 33.04% intronic, 27.56% 5′UTR and 10.46% 3′UTR SNPs and incorporates multiple SNPs per gene allowing gene haplotype network analysis. It was used successfully for the analysis of genetic diversity and population structure of 95 pigeonpea varieties and high resolution mapping of 11 yield related QTLs for number of branches, pod bearing length and number of seeds per pod in a biparental RIL population. As an accurate high-density genotyping tool, ‘CcSNPnks’ chip array will be useful for high resolution fingerprinting, QTL mapping and genome wide as well as gene-based association studies in pigeonpea.

31 July 2023 in Microorganisms
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Shyam PaulShyam Paul
Shyam Paul
SRSavaram Venkata Rama Rao
Savaram Venkata Rama Rao
RCRudra Nath Chatterjee
Rudra Nath Chatterjee
M.V.L.N. RajuM.V.L.N. Raju
M.V.L.N. Raju
DMDr. Ajay Kumar Mahato
Dr. Ajay Kumar Mahato
PKPrakki Santosh Phani Kumar
Prakki Santosh Phani Kumar
Antimicrobial growth promoters (AGP) are used in chicken production to suppress pathogens in the gut and improve performance, but such products tend to suppress beneficial bacteria while favoring the development and spread of antimicrobial resistance. A green alternative to AGP with the ability to suppress pathogens, but with an additional ability to spare beneficial gut bacteria and improve breeding performance is urgently required. We investigated the effect of supplementation of a blend of select essential oils (cinnamon oil, carvacrol, and thyme oil, henceforth referred to as EO; at two doses: 200 g/t and 400 g/t feed) exhibiting an ability to spare Lactobacillus while exhibiting strong E. coli inhibition ability under in vitro tests and immobilized in a sunflower oil and calcium alginate matrix, to broiler chickens and compared the effects with those of a probiotic yeast (Y), an AGP virginiamycin (V), and a negative control (C). qPCR analysis of metagenomic DNA from the gut content of experimental chickens indicated a significantly (p < 0.05) lower density of E. coli in the EO groups as compared to other groups. Amplicon sequence data of the gut microbiome indicated that all the additives had specific significant effects (DESeq2) on the gut microbiome, such as enrichment of uncultured Clostridia in the V and Y groups and uncultured Ruminococcaceae in the EO groups, as compared to the control. LEfSe analysis of the sequence data indicated a high abundance of beneficial bacteria Ruminococcaceae in the EO groups, Faecalibacterium in the Y group, and Blautia in the V group. Supplementation of the immobilized EO at the dose rate of 400 g/ton feed improved body weight gain (by 64 g/bird), feed efficiency (by 5 points), and cellular immunity (skin thickness response to phytoheamagglutinin lectin from Phaseolus vulgaris by 58%) significantly (p < 0.05), whereas neither yeast nor virginiamycin showed a significant effect on performance parameters. Expression of genes associated with gut barrier and immunity function such as CLAUDIN1, IL6, IFNG, TLR2A, and NOD1 were significantly higher in the EO groups. This study showed that the encapsulated EO mixture can improve the density of beneficial microbes in the gut significantly, with concomitant suppression of potential pathogens such as E.coli and improved performance and immunity, and hence, has a high potential to be used as an effective alternative to AGP in poultry.

23 April 2021 in The Journal of Horticultural Science and Biotechnology
Verified
Journal Article
Closed access
SRSridhar Ramachandra
Sridhar Ramachandra
MSManish Srivastav
Manish Srivastav
SSSanjay Kumar Singh
Sanjay Kumar Singh
DMDr. Ajay Kumar Mahato
Dr. Ajay Kumar Mahato
NSNisha Singh
Nisha Singh
Nagendra Kumar SinghNagendra Kumar Singh
Nagendra Kumar Singh
Our aim was to screen new hyper-variable mango SSRs (MSSRs) designed from Amrapali genome sequences to find polymorphic ones between Amrapali and Sensation parental genotypes. Out of 253 MSSRs screened against Amrapali and Sensation genotypes, 212 were polymorphic, of which 8 MSSRs showed aa, bb or bb, aa allelic patterns. MSSRs showing polymorphism in terms of homozygous for ‘a’ allele in Amrapali and homozygous ‘b’ allele for Sensation and vice versa were selected for assignment of parentage of hand-pollinated (Amrapali x Sensation) hybrids and open-pollinated Amrapali. MSSR markers were mapped back to the Amrapali genome version 3.0 NCBI GenBank database. MSSRs (M109, P125, M15, and M73) assigned parentage to more than 88.0% of hand-pollinated hybrids. P125 confirmed parentage of 93.61% progenies followed by M109 (90.43%), M15 (89.36%), and M73 (88.29%). Randomly three MSSRs, viz. M109, P125, and M73, were used for assignment of parentage of OP seedlings of Amrapali. Out of 22 OP seedlings, only 2 seedlings showed the identical heterozygous allelic pattern and their hybrid origin was confirmed. It is concluded that MSSRs (P125, M109, M15, and M73) from the Amrapali genome have immense value in MAS in mango and can be utilised for early stage selection of true hybrids.

14 November 2025 in Scientific Reports
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RERamesh Eerapagula
Ramesh Eerapagula
ASAkshay Singh
Akshay Singh
AMAvantika Maurya
Avantika Maurya
RSRakesh Singh
Rakesh Singh
NSNagendra Kumar Singh
Nagendra Kumar Singh
DMDr. Ajay Kumar Mahato
Dr. Ajay Kumar Mahato
Grain amaranth ( Amaranthus hypochondriacus ) is a climate-resilient pseudo-cereal with high nutritional value and stress tolerance. NAC transcription factors (TFs) are key regulators in plant development and environmental responses. Here, we performed a comprehensive genome-wide analysis of 70 NAC genes ( AhypNACs ), classified into 24 phylogenetic subfamilies. Gene structure analysis showed exon variation (1–7), and chromosomal mapping revealed uneven distribution, with 32 segmental, 5 tandem, and 32 transposed duplications. Promoter analysis identified diverse cis -regulatory elements linked to light, hormone signaling, and stress response. miRNA analysis suggested Ahyp-miR164a targets four NAC genes, indicating post-transcriptional control. Comparative genomics showed both conserved and lineage-specific expansions among Oryza sativa , Beta vulgaris , Arabidopsis thaliana , and Chenopodium quinoa. Transcriptome analysis across seven tissues and five stress conditions identified several condition-specific and multi-stress-responsive NAC genes, with AhypNAC17, AhypNAC23 , and AhypNAC24 showing strong induction. RT-qPCR validation under drought stress confirmed early and sustained upregulation of AhypNAC23 and AhypNAC24 , and downregulation of AhypNAC03 and AhypNAC70 , supporting their functional roles in drought adaptation. This study provides key insights into the structural diversity, evolutionary patterns, and stress-regulatory roles of NAC TFs in A. hypochondriacus , laying the foundation for genetic improvement of stress-resilient cultivars.

Verified
Journal Article
Open access
PDF file
RSRakesh Singh
Rakesh Singh
Akshay SinghAkshay Singh
Akshay Singh
DMDr. Ajay Kumar Mahato
Dr. Ajay Kumar Mahato
RPRitu Paliwal
Ritu Paliwal
GTGunjan Tiwari
Gunjan Tiwari
AKAshok Kumar
Ashok Kumar
Andrographis paniculata belongs to the family Acanthaceae and is known for its medicinal properties owing to the presence of unique constituents belonging to the lactones, diterpenoids, diterpene glycosides, flavonoids, and flavonoid glycosides groups of chemicals. Andrographolide, a major therapeutic constituent of A. paniculata, is extracted primarily from the leaves of this plant and exhibits antimicrobial and anti-inflammatory activities. Using 454 GS-FLX pyrosequencing, we have generated a whole transcriptome profile of entire leaves of A. paniculata. A total of 22,402 high-quality transcripts were generated, with an average transcript length and N50 of 884 bp and 1007 bp, respectively. Functional annotation revealed that 19,264 (86%) of the total transcripts showed significant similarity with the NCBI-Nr database and were successfully annotated. Out of the 19,264 BLAST hits, 17,623 transcripts were assigned GO terms and distributed into three major functional categories: molecular function (44.62%), biological processes (29.19%), and cellular component (26.18%) based on BLAST2GO. Transcription factor analysis showed 6669 transcripts, belonging to 57 different transcription factor families. Fifteen TF genes that belong to the NAC, MYB, and bHLH TF categories were validated by RT PCR amplification. In silico analysis of gene families involved in the synthesis of biochemical compounds having medicinal values, such as cytochrome p450, protein kinases, heat shock proteins, and transporters, was completed and a total of 102 different transcripts encoding enzymes involved in the biosynthesis of terpenoids were predicted. Out of these, 33 transcripts belonged to terpenoid backbone biosynthesis. This study also identified 4254 EST-SSRs from 3661 transcripts, representing 16.34% of the total transcripts. Fifty-three novel EST-SSR markers generated from our EST dataset were used to assess the genetic diversity among eighteen A. paniculata accessions. The genetic diversity analysis revealed two distinct sub-clusters and all accessions based on the genetic similarity index were distinct from each other. A database based on EST transcripts, EST-SSR markers, and transcription factors has been developed using data generated from the present study combined with available transcriptomic resources from a public database using Meta transcriptome analysis to make genomic resources available in one place to the researchers working on this medicinal plant.