title: Identification of quantitative trait loci for yield and yield related traits in groundnut (Arachis hypogaeaL.) under different water regimes in Niger and Senegal.
abstract: Yield under drought stress is a highly complex trait with large influence to even a minor fluctuation in the environmental conditions. Genomics-assisted breeding holds great promise for improving such complex traits more efficiently in less time, but requires markers associated with the trait of interest. In this context, a recombinant inbred line mapping population (TAG 24 × ICGV 86031) was used to identify markers associated with quantitative trait loci (QTLs) for yield and yield related traits at two important locations of West Africa under well watered and water stress conditions. Among the traits analyzed under WS condition, the harvest index (HI) and the haulm yield (HYLD) were positively correlated with the pod yield (PYLD) and showed intermediate broad sense heritability. QTL analysis using phenotyping and genotyping data resulted in identification of 52 QTLs. These QTLs had low phenotypic variance (<12 %) for all the nine traits namely plant height, primary branching, SPAD chlorophyll meter reading, percentage of sound mature kernels, 100 kernel weight, shelling percentage, HI, HYLD and PYLD. Interestingly, few QTLs identified in this study were also overlapped with previously reported QTLs detected for drought tolerance related traits identified earlier in Indian environmental conditions using the same mapping population. Accumulating these many small-effect QTLs into a single genetic background is nearly impossible through marker-assisted backcrossing and even marker-assisted recurrent selection. Under such circumstances, the deployment of genomic selection is the most appropriate approach for improving such complex traits with more precision and in less time.
authors.affiliation: Institut Sénégalais de Recherches Agricoles (ISRA)-Centre National de Recherches Agronomiques (CNRA), BP 53, Bambey, Senegal.
authors.forename: Issa
authors.initials: I
authors.lastname: Faye
authors.affiliation: International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, 502 324 India.
authors.forename: Manish K
authors.initials: MK
authors.lastname: Pandey
authors.affiliation: International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Sahelian Center, 12404 Niamey, Niger ; Department of Biology, Faculty of Sciences, University Abdou Moumouni, BP 10662, Niamey, Niger.
authors.forename: Falalou
authors.initials: F
authors.lastname: Hamidou
authors.affiliation: International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, 502 324 India.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Rathore
authors.affiliation: Institut Sénégalais de Recherches Agricoles (ISRA)-Centre National de Recherches Agronomiques (CNRA), BP 53, Bambey, Senegal.
authors.forename: Ousmane
authors.initials: O
authors.lastname: Ndoye
authors.affiliation: International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, 502 324 India.
authors.forename: Vincent
authors.initials: V
authors.lastname: Vadez
authors.affiliation: International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, 502 324 India.
authors.forename: Rajeev K
authors.initials: RK
authors.lastname: Varshney
keywords: Drought tolerance; Epistatic QTLs; Main-effect QTLs; Pod yield; Quantitative trait locus