Publications des agents du Cirad


Mapping QTLs for Black pod (Phytophthora palmivora) resistance in three hybrid progenies of cocoa (Theobroma cacao L.) using SSR markers

Akaza J.M., Kouassi A.B., Akaffou D.S., Fouet O., N'Guetta A.S.P., Lanaud C.. 2016. International Journal of Scientific and Research Publications, 6 (1) : p. 298-311.

To identify QTLs for cacao resistance to Phytopthorapalmivora., a study was conducted in three hybrid progenies of CNRA in Côte d'Ivoire obtained from crosses (SCA6 x H) x C1, (P7 x ICS100) x C1 and (P7 x ICS95 x) x C1. SCA6 (Scavina 6) and P7 (Pound 7) are resistant Forastero clones, while ICS100, ICS95 and H are moderately susceptible Trinitario clones and C1 (IFC1), a susceptible Forastero clone. Resistance to P. palmivorawas assessed by means of pod rot rate (PRR) in field and leaf discs inoculation with zoospores (Folres) in both half-sib progenies, while only PRR was investigated in the progeny derived from (SCA6 x H) x C1. For each progeny, a SSR-based linkage map was constructed and Kruskal-Wallis test and interval mapping were applied, associating phenotypic data. Over the three progenies, 8 QTLs of PRR and 3 QTLs of Folres were detected on different chromosomes. One QTL of Folres (R2 = 17.3 %) has been identified on chromosome 10, for the first time. The chromosome 1, carrying QTLs of PRR and Folres, is an interesting support of cacao resistance to Phytophthora. Chromosomes 4 and 6, each, of of two different parents carry QTLs of PRR In addition, the association mTcCIR291-PRR, on the chromosome 6 was noted in the family derived from (SCA6 x H) x C1, as well as in one of the two half-sib families. Markers linked to QTLs are valuable potential candidates for a future exploiting of these QTLs as selection tools.

Mots-clés : theobroma cacao; phytophthora palmivora; locus des caractères quantitatifs; résistance génétique; carte génétique; marqueur génétique; résistance aux maladies; phénotype; séquence nucléotidique; côte d'ivoire; qtl; ssr

Documents associés

Article (b-revue à comité de lecture)

Agents Cirad, auteurs de cette publication :