title: Performance and grain yield stability of maize populations developed using marker-assisted recurrent selection and pedigree selection procedures.
abstract: A marker-assisted recurrent selection (MARS) program was undertaken in sub-Saharan Africa to improve grain yield under drought-stress in 10 biparental tropical maize populations. The objectives of the present study were to evaluate the performance of C1S2-derived hybrids obtained after three MARS cycles (one cycle of recombination (C1), followed by two generations of selfing (S2), and to study yield stability under both drought-stress (DS) and well-watered (WW) conditions. For each of the 10 populations, we evaluated hybrids developed by crossing 47-74 C1S2lines advanced through MARS, the best five S5lines developed through pedigree selection, and the founder parents with a single-cross tester from a complementary heterotic group. The hybrids and five commercial checks were evaluated in Kenya under 1-3 DS and 3-5 WW conditions with two replications. Combined across DS locations, the top 10 C1S2-derived hybrids from each of the 10 biparental populations produced 0.5-46.3 and 11.1-55.1 % higher mean grain yields than hybrids developed using pedigree selection and the commercial checks, respectively. Across WW locations, the best 10 hybrids derived from C1S2of each population produced 3.4-13.3 and 7.9-36.5 % higher grain yields than hybrids derived using conventional pedigree breeding and the commercial checks, respectively. Mean days to anthesis of the best 10 C1S2hybrids were comparable to those of hybrids developed using the pedigree method, the founder parents and the commercial checks, with a maximum difference of 3.5 days among the different groups. However, plant height was significantly (P < 0.01) different in most pairwise comparisons. Our results showed the superiority of MARS over pedigree selection for improving diverse tropical maize populations as sources of improved lines for stress-prone environments and thus MARS can be effectively integrated into mainstream maize breeding programs.
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 1041, Village Market, Nairobi, 00621 Kenya.
authors.forename: Yoseph
authors.initials: Y
authors.lastname: Beyene
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 1041, Village Market, Nairobi, 00621 Kenya.
authors.forename: Kassa
authors.initials: K
authors.lastname: Semagn
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 1041, Village Market, Nairobi, 00621 Kenya.
authors.forename: Stephen
authors.initials: S
authors.lastname: Mugo
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 1041, Village Market, Nairobi, 00621 Kenya.
authors.forename: Boddupalli M
authors.initials: BM
authors.lastname: Prasanna
authors.affiliation: CIMMYT, 12.5 km peg Mazowe Road, Mount Pleasant, P.O. Box MP163, Harare, Zimbabwe.
authors.forename: Amsal
authors.initials: A
authors.lastname: Tarekegne
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 1041, Village Market, Nairobi, 00621 Kenya.
authors.forename: John
authors.initials: J
authors.lastname: Gakunga
authors.affiliation: Monsanto SAS, Croix de Pardies, BP21, 40305 Peyrehorade, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Sehabiague
authors.affiliation: Monsanto South Africa (Pty) Ltd, P.O. Box 69933, Bryanston, 2021 South Africa.
authors.forename: Barbara
authors.initials: B
authors.lastname: Meisel
authors.affiliation: African Agricultural Technology Foundation (AATF), P.O. Box 30709-00100, Nairobi, Kenya.
authors.forename: Sylvester O
authors.initials: SO
authors.lastname: Oikeh
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), P.O. Box 1041, Village Market, Nairobi, 00621 Kenya.
authors.forename: Michael
authors.initials: M
authors.lastname: Olsen
authors.affiliation: International Maize and Wheat Improvement Center (CIMMYT), Apdo. Postal 6-641, 06600 Mexico, DF Mexico.
authors.forename: Jose
authors.initials: J
authors.lastname: Crossa
keywords: Africa; Drought; Molecular breeding; Rapid cycle recombination; SNP; Testcross evaluation