Molecular mapping of QTLs for plant type and earliness traits in pigeonpea (Cajanus cajanL. Millsp.)

BMC Genetics

Research Article

Ranjeet S Raje¹  Nagendra K Singh²  Kishor Gaikwad²  Amitha SVCR Mithra²  Jitendra K Pal²  Shefali Bhutani²  Tilak R Sharma²  Giriraj Kumawat³ 

[1] Division of Genetics, Indian Agricultural Research Institute, 110012, New Delhi, India;National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute, 110012, New Delhi, India;National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute, 110012, New Delhi, India;Directorate of Soybean Research, 452001, Indore, Madhya Pradesh, India;

关键词: Earliness;    Pigeonpea;    Plant height;    QTL mapping;    SSR marker;    SNP marker;   

DOI  :  10.1186/1471-2156-13-84

 received in 2012-05-08, accepted in 2012-09-28,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundPigeonpea is an important grain legume of the semi-arid tropics and sub-tropical regions where it plays a crucial role in the food and nutritional security of the people. The average productivity of pigeonpea has remained very low and stagnant for over five decades due to lack of genomic information and intensive breeding efforts. Previous SSR-based linkage maps of pigeonpea used inter-specific crosses due to low inter-varietal polymorphism. Here our aim was to construct a high density intra-specific linkage map using genic-SNP markers for mapping of major quantitative trait loci (QTLs) for key agronomic traits, including plant height, number of primary and secondary branches, number of pods, days to flowering and days to maturity in pigeonpea.ResultsA population of 186 F2:3 lines derived from an intra-specific cross between inbred lines ‘Pusa Dwarf’ and ‘HDM04-1’ was used to construct a dense molecular linkage map of 296 genic SNP and SSR markers covering a total adjusted map length of 1520.22 cM for the 11 chromosomes of the pigeonpea genome. This is the first dense intra-specific linkage map of pigeonpea with the highest genome length coverage. Phenotypic data from the F2:3 families were used to identify thirteen QTLs for the six agronomic traits. The proportion of phenotypic variance explained by the individual QTLs ranged from 3.18% to 51.4%. Ten of these QTLs were clustered in just two genomic regions, indicating pleiotropic effects or close genetic linkage. In addition to the main effects, significant epistatic interaction effects were detected between the QTLs for number of pods per plant.ConclusionsA large amount of information on transcript sequences, SSR markers and draft genome sequence is now available for pigeonpea. However, there is need to develop high density linkage maps and identify genes/QTLs for important agronomic traits for practical breeding applications. This is the first report on identification of QTLs for plant type and maturity traits in pigeonpea. The QTLs identified in this study provide a strong foundation for further validation and fine mapping for utilization in the pigeonpea improvement.

【 授权许可】

Unknown   
© Kumawat et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.