Advertisement
Utilizing genomic resources for understanding the stay-green QTLs interactions in Sorghum
Upcoming SlideShare
Fast forward genetic mapping provides candidate genes for resistance to fusar...Fast forward genetic mapping provides candidate genes for resistance to fusar...
Loading in ... 3
1 of 1
Advertisement

More Related Content

Slideshows for you(20)

Advertisement

Similar to Utilizing genomic resources for understanding the stay-green QTLs interactions in Sorghum(20)

More from ICRISAT(20)

Advertisement

Utilizing genomic resources for understanding the stay-green QTLs interactions in Sorghum

  1. About ICRISAT: www.icrisat.org ICRISAT’s scientific information: http://EXPLOREit.icrisat.org Feb 2017 Poster- IDT7-054 Utilizing genomic resources for understanding the stay-green QTLs interactions in Sorghum Manasa K G1, Santosh P Deshpande1* 1International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, India * Email: s.deshpande@cgiar.org Abstract Sorghum [Sorghum bicolor (L.) Moench] is a fifth most important cereal crop in the world providing food, fodder/forage and bio-fuel. The postrainy sorghum crop in India is grown on residual moisture and inadvertently faces terminal drought. “Stay-green” (delayed senescence) is a post-flowering drought tolerance response, which help plants to maintain photosynthetically active leaf area and continue to fill their grains normally under stress. Sorghum crop is referred to express functional type of stay-green and the trait has been mapped to six major QTLs viz., Stg1, Stg2, Stg3A, Stg3B, StgC and Stg4. However, the gap in understanding the key mechanism has not been deciphered clearly. In this scenario to understand the actual mechanism of the stay-green pathway the information from different crops on candidate genes responsible for stay-green phenotype were considered viz., STAY-GREEN (SGR) along with one or two homologous (SGR1or NYE1/SGRL); Pheophytin Pheophorbide Hydrolase (PPH); Pheophorbide a Oxygenase (PAO); Red Chlorophyll Catabolite Reductase (RCCR); Non-Yellow Coloring (NYC) and it’s homologous NYC1-Like (NOL); 7-Hydroxymethyl Chlorophyll a Reductase (HCAR) from Zea mays, Arabidopsis thaliana and Orzya sativa. Apart from these, senescence associated genes SAG2, SAG102 and SAG39 were also considered from Arabidopsis thaliana and Orzya sativa respectively. The sequence and functional/annotation information for these genes retrieved for sequence similarity search and it has revealed 45 to 88 % of similarity in sorghum. The mapping of these candidate gene sequences within the defined QTL regions contributing for Stay-green has given an insight to utilize the re-sequencing data for improved drought tolerance in sorghum. Hypothetical understanding of stay green trait in sorghum based on the review of stay green associated genes in Arabidopsis thaliana (Reference: Sakuraba et al, 2015, molcells.0039; Thomas, H. and Howarth, C.J. 2000, J.Exp. Bot. 51, 329-337.) RCCRHCAR PPH NYC PAONOL Senescence triggering (SAG) Abiotic stress at maturity (Post flowering) Senescence associated complex Senescence Genes responsible for regular transition from vegetative to senescence Stg A, Stg B Genes responsible for regular transition from vegetative to senescence Stg A, Stg B HCAR RCCR PPH NYC PAO NOL Stress induced signaling Unknown gene Stg Z Senescence triggering (SAG) At maturity Senescence associated complex Genes responsible for regular transition from vegetative to senescence Stg A, Stg B Genes responsible for regular transition from vegetative to senescence Stg A, Stg B HCAR RCCR PPH NYC PAO NOL Senescence RCCRHCAR PPH NYC PAONOL  Candidate gene information from different model organisms were considered to construct circos and check synteny among different species with respect to sorghum. SGR and it’s homologous genes were mapped to Stg3A and Stg3B QTLs of SBI-02 indicating these could be putative candidates. However other genes involved in the mechanism were mapped to other major and minor QTLs located on SBI- 01, SBI-03, SBI-05 and SBI-07.  Protein sequence for SGR gene was retrieved from Genome database, Multiple sequence alignment using T-coffee software was done to compare the homology. Highest percentage similarity was observed with Zea mays up to 88% indicating the presence of similar kind of candidate gene for Stay-green in Sorghum. Results and Conclusions Acknowledgements Conclusions Reviewing the reports on Stay-green candidate gene studies from other organisms and comparing the results at gene (Circos), protein (alignment) and mechanism (Hypothesis) level helped in understanding the relationship between senescence and stay-green trait. Many of the genes involved in the mechanism are mapped to known Stay-green QTL regions giving insight to utilize the re-sequencing data to address knowledge gap for developing tools /markers and their utilization in breeding for better adaptation to drought scenarios. Financial support from GCP, ACIAR and CRP-DC is greatly acknowledged. Alignment of SGR Protein sequences from Arabidopsis, rice, maize and sorghum using T-coffee software for comparison Analogy of Stay-green candidate genes from other model organism viz., Arabidopsis, rice and maize on sorghum genome. Linkage map of Sorghum Stay-green QTLs Stg 4
Advertisement