Use of QTL detected for resistance to Phytophthora in Theobroma cacao L.

Lanaud Claire, Flament Marie-Henriette, Nyassé Salomon, Risterucci Ange-Marie, Fargeas Dominique, Kébé Ismael S., Sounigo Olivier, Motilal Lambert A., Thévenin Jean-Marc, Paulin Didier, Ducamp Michel, Clément Didier, Tahi G.Mathias, Bidzanga Nomo Lucien, N'Goran Jeanne A.K., Despréaux Denis, Cilas Christian. 2000. Use of QTL detected for resistance to Phytophthora in Theobroma cacao L.. In : Proceedings of the international workshop on the new technologies and cocoa breeding: abstracts. INGENIC. Reading : INGENIC, p. 14. International Workshop on New Technologies and Cocoa Breeding. 3, Kota Kinabalu, Malaisie, 16 October 2000/17 October 2000.

Paper without proceedings
Published version - Anglais
Use under authorization by the author or CIRAD.

Télécharger (1MB) | Preview

Additional Information : Résumé seul

Abstract : In the framework of a CAOBISCO sponsored project the genetic bases of resistance to several species of Phytophthora have been studied. Different significative QTL identified make it possible to accumulate various resistance genes to improve varietal resistance. Markers closely linked to QTL could allow to control at early stages the presence of resistance alleles in progenies. Several applications or strategies using QTL analyses could be considered to improve resistance level. Creation of genotypes homozygous for resistance alleles.The most resistant clones, as SCA6 and SNK413, could have the resistance genes in an homozygous condition. The identification of a QTL means a heterozygous condition of the resistance gene identified in the parent studied. By selfing the genotypes and using Marker Assisted Selection (MAS), it is possible to produce and screen selfed progenies having homozygous resistance alleles. These clones will have a higher resistance level and a better combining ability to produce resistant hybrids. Accumulation of various resistance genes and other genes of interest Various resistance genes could be accumulated using MAS by crossing clones for which different QTL of resistance have been identified. It is also possible to use MAS to break linkage between favourable and unfavourable alleles located in the same chromosome region. Early selection for resistance and other traits. Increased selection efficiency in pre-breeding, at the nursery stage, would be possible by applying MAS on a limited number of resistance QTL (stronger QTL, QTL for resistance to several Phytophthora species...) and to have available more plants to apply selection for other traits of interest in the field. Combine use of marker information and phenotypic selection to constitute a selection index. Information.,; on a larger number of QTL could be combined with phenotypic selection related to resistance traits (intrinsic resistance revealed by leaf tests) or other traits of interest to constitute a selection index. Apply MAS at other sites than those where QTL have been identified. It is possible to accumulate QTL identified at- different sites for diseases not present in the country (examples : screening in Montpellier for resistance to P. palmivora, P. megakarya, P. capsici, or possible selection of field resistance to P. megakarya on the basis of QTL identified in Cameroon). The first results obtained in the CAOBISCO project allow to put in place several experiments to test MAS strategies (selfing clones to fix resistance genes in homozygous condition, accumulating various resistance genes). However the identification of QTL in important Other resistant ciones has to be continued to identify the all major sources of resistance to Phytophthora in cocoa. (Résumé d'auteur)

Classification Agris : F30 - Plant genetics and breeding
H20 - Plant diseases

Auteurs et affiliations

  • Lanaud Claire, CIRAD-AMIS-BIOTROP (FRA) ORCID: 0000-0001-6411-7310
  • Flament Marie-Henriette, CIRAD-CP-CACAO (FRA)
  • Nyassé Salomon, IRAD (CMR)
  • Risterucci Ange-Marie, CIRAD-AMIS-BIOTROP (FRA)
  • Fargeas Dominique, CIRAD-AMIS-BIOTROP (FRA)
  • Kébé Ismael S., CNRA (CIV)
  • Sounigo Olivier, CIRAD-CP-CACAO (TTO) ORCID: 0000-0001-6278-8903
  • Motilal Lambert A., UWI (TTO)
  • Thévenin Jean-Marc, CIRAD-CP-CACAO (TTO)
  • Paulin Didier, CIRAD-CP-CACAO (FRA)
  • Ducamp Michel, CIRAD-CP-CACAO (FRA)
  • Clément Didier, CIRAD-CP-CACAO (FRA) ORCID: 0000-0002-7602-6472
  • Tahi G.Mathias, CNRA (CIV)
  • Bidzanga Nomo Lucien, IRAD (CMR)
  • N'Goran Jeanne A.K., CNRA (CIV)
  • Despréaux Denis, CIRAD-CP-DIR (FRA)
  • Cilas Christian, CIRAD-CP-CACAO (FRA)

Autres liens de la publication

Source : Cirad - Agritrop (

View Item (staff only) View Item (staff only)

[ Page générée et mise en cache le 2020-07-22 ]