African Journal of Biotechnology Vol. 6 (4), pp. 341-347, 19 February 2007   

ISSN 1684–5315 © 2007 Academic Journals        

Full Length Research Paper

Microsatellite gene diversity in coconut (Cocos nucifera L.) accessions resistants to lethal yellowing disease

Konan K. Jean Noël^{1, 2}, Koffi Kouablan Edmond¹, Konan Jean Louïs³, Lebrun Patricia⁴, Dery S. K.⁵ and Sangare Abdourahamane¹

¹Laboratoire Central de Biotechnologies, Km17 Route Dabou, 01 BP 1740 Abidjan     01, Côte d’Ivoire.

²Laboratoire de Génétique, UFR Biosciences Université de Cocody – 22 BP 582 Abidjan 22, RCI.

³Station Marc Delorme de Port Bouët, 07 BP 13 Abidjan 07, Côte d’Ivoire.

⁴Centre de coopération International en Recherche Agronomique pour le Développement, Avenue Agropolis 34398 Montpellier Cedex 5, France.

⁵Coconut program Institute, P.O. Box 245, Sekondi, Ghana.

*Corresponding author. E-mail: konan_jeannoel@yahoo.fr.  Tel: +225 23 47 24 14.

Accepted 13 December, 2006

One of the problems faced in coconut cultivation is the lethal yellowing disease. Experimental trials, conducted in endemic region, showed that the Vanuatu Tall and Sri-Lanka Green Dwarf genotypes were tolerant while the West African Tall appeared susceptible to the lethal yellowing disease. Genetic differences between these tolerant genotypes and the susceptible ones were evaluated using twelve microsatellite markers. This work aimed to use identified materials as reference to select suitable parents for gene mapping studies. A total of 58 alleles were detected at the 12 microsatellite loci. The number of alleles varied from 3 to 7, with an average of 4.83 alleles. The F_st index revealed that 59.70% of the total allele variability explained differences between the three accessions. Genotypes of West African Tall, susceptible to the lethal yellowing disease, were less genetically clustered to the genotypes of the two tolerant accessions. This differentiation was based on specific alleles and frequency variation of shared allele in the three accessions. This molecular typology was useful as reference for large molecular screening of coconut genetic resources and the identification of suitable parents for the development of mapping populations for tagging the lethal yellowing resistance genes.

Key words: Coconut tree, lethal yellowing disease, microsatellite, tolerance.