Genotypic variation and identification of QTLs for agronomic traits, using AFLP and SSR markers in RILs of sunflower (Helianthus annuus L.)

• Published in: Theoretical and applied genetics Vol. 109; no. 7; pp. 1353 - 1360
• Main Authors: RACHID, G, AL-CHAARANI, GENTZBITTEL, L, HUANG, X. Q, SARRAFI, A
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.11.2004; Berlin Springer Nature B.V
• Subjects: Analysis of Variance; Biological and medical sciences; Chromosome Mapping; Chromosomes, Plant - genetics; Classical genetics, quantitative genetics, hybrids; Crosses, Genetic; Fundamental and applied biological sciences. Psychology; Genetic Markers; Genetic Variation; Genetics; Genetics of eukaryotes. Biological and molecular evolution; Genomics; Helianthus - genetics; Helianthus annuus; Pteridophyta, spermatophyta; Quantitative Trait Loci; Vegetals; Helianthus annuus; Dicotyledones; Quantitative character; Angiospermae; Genetics; Spermatophyta; Agriculture; Identification; Molecular marker; Compositae
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-004-1770-1

A population of 77 recombinant inbred lines (RILs) were developed through single-seed descent from a cross between 'PAC-2' and 'RHA-266'. Seeds of the above-mentioned RILs and their parents were planted in the field in a randomised complete block design with two replications. Genetic control for some agronomical traits-sowing-to-flowering date, plant height, stem diameter (SD), head diameter (HD), grain weight per plant, 1,000-grain weight (TGW) and the percentage of oil in grains-were measured for RILs and their parents. Genetic variability was observed among 77 RILs for all traits studied. Transgressive segregation occurred for some traits, and the comparison between 10% of selected RILs with the best parent showed significant difference for SD and HD as well as for TGW. A set of 123 RILs from the same cross, including the 77 above-mentioned RILs and their two parents, were screened with 409 AFLP and SSR markers, and a linkage map was constructed based on 367 markers. Several QTLs associated with the studied traits were identified. The effects of each QTL are moderate, ranging from 7% to 37%, but a high percentage of phenotypic variance is explained when considering all the covariants (TR2 mean around 80% in each trait). Although the detected regions need to be more precisely mapped, the information obtained should help in marker-assisted selection.