Abstract

After 20 years of conservation of accessions of Tall coconut palms in the International Coconut Collection for Africa and the Indian Ocean (ICC-AIO), they become unusable because of the hight of the coconut palms which makes variety creation operations difficult. The regeneration of old accessions was therefore undertaken. However, the representativeness of the parental palms used as male or female genitors during the regeneration cycles is not known. So, the success of the regeneration method in terms of the representativeness of the parental genotypes used as genitors has never been evaluated. This work aimed to characterize the of controlled pollinationand method and to evaluate the representativeness of the parental genotypes used during the regeneration of the Tall coconut accessions. The results shwon that to regenerate a Tall coconut accession with n individuals, 2.11 n controlled pollinations must be carried out. In addition, the analysis highlighted differences in the representativeness of the parental genotypes sampled during the regeneration process of a Tall coconut palm accession by controlled pollination. These differences in the representativeness of the parental genotypes are caused by the mortality in the field of the regenerated plants planted, the excessive height of certain parental genotypes as well as their low seed yield by controlled pollination. The evolution of the diversity level of the offspring from the parental genotypes used at each regeneration cycle showed a reduction. Nowadays, in regeneration programmes for ex situ or field collections of coconut palms or other perennial plants, it is essential to take pedigree into account when choosing the genitors to be used in crosses, in order to maintain maximum diversity in the regenerated generations of accessions.

Key words: Cocos nucifera L., tall ecotypes, ex situ collection, rejuvenation, Côte d’Ivoire.