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Yield-associated putative gene regulatory networks in Oryza sativa L. subsp. indica and their association with high-yielding genotypes

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Background With the increase in population and economies of developing countries in Asia and Africa, the research towards securing future food demands is an imminent need. Among japonica and indica genotypes, indica rice varieties are largely cultivated across the globe. However, our present understanding of yield-contributing gene information stems mainly from japonica and studies on the yield potential of indica genotypes are limited. Methods and results In the present study, yield contributing orthologous genes previously characterized from japonica varieties were identified in the indica genome and analysed with binGO tool for GO biological processes categorization. Transcription factor binding site enrichment analysis in the promoters of yield-related genes of indica was performed with MEME-AME tool that revealed putative common TF regulators are enriched in flower development, two-component signalling and water deprivation biological processes. Gene regulatory networks revealed important TF-target interactions that might govern yield-related traits. Some of the identified candidate genes were validated by qRT-PCR analysis for their expression and association with yield-related traits among 16 widely cultivated popular indica genotypes. Further, SNP-metabolite-trait association analysis was performed using high-yielding indica variety Rasi. This resulted in the identification of putative SNP variations in TF regulators and targeted yield genes significantly linked with metabolite accumulation. Conclusions The study suggests some of the high yielding indica genotypes such as Ravi003, Rasi and Kavya could be used as potential donors in breeding programs based on yield gene expression analysis and SNP-metabolites associations.
Grain yield-based phenotypic association of 16 Oryza sativa (indica group) genotypes. Correlation of phenotypic variations related to different yield attributes classified 16 rice indica genotypes into high, medium and low yield. a Pearson correlation coefficients among 9 yield attributes (DTM days to maturity, PH plant height, PL panicle length, NP number of panicles, NFG, number of filled grains, TSW thousand grain weight, NSP number of spikelets/plant, SF spikelet fertility and GYP grain yield/plant) during the plant growth. Positive correlations are denoted in red and negative correlations in blue color. Circle size and color intensity represents correlation coefficients. b Comparative plot of NFG and NSP phenotypic attributes in 16 rice indica genotypes. The X-axis and Y-axis represents rice indica genotype names and quantitative value, respectively. Based on the significant variations in the phenotypic attributes, 16 genotypes were considered as high, medium and low yield. The color palette is indicated on the right of the plot. The represented data are means of three biological replicates. Vertical bars indicate the standard error. The complete statistical analyses are provided in Table S2b. c Expression validation of known candidate target genes was performed using qPCR in flag leaf and young panicle of 16 indica rice genotypes. The specific primers used are listed in Table S2e. The colour scale for transcript abundance levels are shown at the right side of the figure along with genotype and tissue information. The represented transcript abundances are means of three biological replicates. The complete statistical analyses are provided in Table S2c and Table S2d
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Molecular Biology Reports (2022) 49:7649–7663
https://doi.org/10.1007/s11033-022-07581-0
ORIGINAL ARTICLE
Yield‑associated putative gene regulatory networks inOryza sativa L.
subsp. indica andtheir association withhigh‑yielding genotypes
AparnaEragam1,2· VishnuShukla2· VijayaSudhakararaoKola2· P.Latha3· SrividhyaAkkareddy3·
MadhaviL.Kommana4· EswarayyaRamireddy2 · LakshminarayanaR.Vemireddy1
Received: 27 January 2022 / Accepted: 6 May 2022 / Published online: 25 May 2022
© The Author(s), under exclusive licence to Springer Nature B.V. 2022
Abstract
Background With the increase in population and economies of developing countries in Asia and Africa, the research towards
securing future food demands is an imminent need. Among japonica and indica genotypes, indica rice varieties are largely
cultivated across the globe. However, our present understanding of yield-contributing gene information stems mainly from
japonica and studies on the yield potential of indica genotypes are limited.
Methods and results In the present study, yield contributing orthologous genes previously characterized from japonica
varieties were identified in the indica genome and analysed with binGO tool for GO biological processes categorization.
Transcription factor binding site enrichment analysis in the promoters of yield-related genes of indica was performed with
MEME-AME tool that revealed putative common TF regulators are enriched in flower development, two-component sig-
nalling and water deprivation biological processes. Gene regulatory networks revealed important TF-target interactions
that might govern yield-related traits. Some of the identified candidate genes were validated by qRT-PCR analysis for their
expression and association with yield-related traits among 16 widely cultivated popular indica genotypes. Further, SNP-
metabolite-trait association analysis was performed using high-yielding indica variety Rasi. This resulted in the identifica-
tion of putative SNP variations in TF regulators and targeted yield genes significantly linked with metabolite accumulation.
Conclusions The study suggests some of the high yielding indica genotypes such as Ravi003, Rasi and Kavya could be
used as potential donors in breeding programs based on yield gene expression analysis and SNP-metabolites associations.
Keywords Rice· Oryza sativa L.· Gene regulatory networks· Gene expression· SNP-metabolite associations· Yield and
high-yielding genotypes
* Eswarayya Ramireddy
eswar.ramireddy@iisertirupati.ac.in
* Lakshminarayana R. Vemireddy
vlnreddy@angrau.ac.in
Aparna Eragam
aparnareddy003@gmail.com
Vishnu Shukla
vishnushukla@iisertirupati.ac.in
Vijaya Sudhakararao Kola
vijayasudhakarkola@rediffmail.com
P. Latha
p.latha@angrau.ac.in
Srividhya Akkareddy
a.srividhya@angrau.ac.in
Madhavi L. Kommana
madhavi2011040@gmail.com
1 Department ofMolecular Biology andBiotechnology, S.V.
Agricultural College, Acharya NG Ranga Agricultural
University (ANGRAU), Tirupati517502, India
2 Biology Division, Indian Institute ofScience Education
andResearch Tirupati (IISER Tirupati), Tirupati517507,
India
3 Regional Agricultural Research Station (RARS), ANGRAU ,
Tirupati, India
4 Department ofGenetics andPlant Breeding,
S.V. Agricultural College, Acharya NG Ranga Agricultural
University (ANGRAU), Tirupati517502, India
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