title: Mapping and characterisation of QTL x E interactions for traits determining grain and stover yield in pearl millet.
abstract: A mapping population of 104 F(3) lines of pearl millet, derived from a cross between two inbred lines H 77/833-2 x PRLT 2/89-33, was evaluated, as testcrosses on a common tester, for traits determining grain and stover yield in seven different field trials, distributed over 3 years and two seasons. The total genetic variation was partitioned into effects due to season (S), genotype (G), genotype x season interaction (G x S), and genotype x environment-within-season interaction [G x E(S)]. QTLs were determined for traits for their G, G x S, and G x E(S) effects, to assess the magnitude and the nature (cross over/non-crossover) of environmental interaction effects on individual QTLs. QTLs for some traits were associated with G effects only, while others were associated with the effects of both G and G x S and/or G, G x S and G x E(S) effects. The major G x S QTLs detected were for flowering time (on LG 4 and LG 6), and mapped to the same intervals as G x S QTLs for several other traits (including stover yield, harvest index, biomass yield and panicle number m(-2)). All three QTLs detected for grain yield were unaffected by G x S interaction however. All three QTLs for stover yield (mapping on LG 2, LG 4 and LG 6) and one of the three QTLs for grain yield (mapping on LG 4) were also free of QTL x E(S) interactions. The grain yield QTLs that were affected by QTL x E(S) interactions (mapping on LG 2 and LG 6), appeared to be linked to parallel QTL x E(S) interactions of the QTLs for panicle number m(-2) on (LG 2) and of QTLs for both panicle number m(-2) and harvest index (LG 6). In general, QTL x E(S) interactions were more frequently observed for component traits of grain and stover yield, than for grain or stover yield per se.
authors.affiliation: Institute of Grassland and Environmental Research (IGER), Plas Gogerddan, Aberystwyth, Ceredigion, SY23 3EB Wales, UK. rattan.yadav@bbsrc.ac.uk
authors.forename: R S
authors.initials: RS
authors.lastname: Yadav
authors.forename: F R
authors.initials: FR
authors.lastname: Bidinger
authors.forename: C T
authors.initials: CT
authors.lastname: Hash
authors.forename: Y P
authors.initials: YP
authors.lastname: Yadav
authors.forename: O P
authors.initials: OP
authors.lastname: Yadav
authors.forename: S K
authors.initials: SK
authors.lastname: Bhatnagar
authors.forename: C J
authors.initials: CJ
authors.lastname: Howarth
mesh_terms: D002874:Chromosome Mapping; D003433:Crosses, Genetic; D004777:Environment; D008040:Genetic Linkage; D005819:Genetic Markers; D005838:Genotype; D031782:Pennisetum / Q000235:genetics*; D010641:Phenotype; D040641:Quantitative Trait Loci; D019655:Quantitative Trait, Heritable
chemical_list: D005819:Genetic Markers