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Les descripteurs qualitatifs ont été toujours négligés dans les études de caractérisation du cocotier surtout chez les écotypes de type Grand. Cet article se propose de mettre en évidence la contribution de six caractères morphologiques de type qualitatif dans la description et la typologie de 18 populations de cocotier Grand plantées dans la collection internationale de Côte d’Ivoire. Pour y arriver les stipes, les inflorescences, les fleurs femelles et les fruits ont été observés. Compte tenu à la fois de leurs fortes valeurs d’indice de diversité de Shannon normalisé (H’ variant entre 0,93 et 0,99) et faibles valeurs d’indice de diversité de Simpson (D variant entre 0,24 et 0,28), les caractères formes du fruit et de la noix débourrée ont été les plus discriminants. Les résultats de la classification des populations de cocotier Grand de la collection de Côte d’Ivoire utilisant les caractères qualitatifs sont en désaccord avec la structuration admise et fournie antérieurement à partir des marqueurs morphologiques quantitatifs et moléculaires microsatellites (SSRs). Bien que longtemps marginalisé dans l’étude de la diversité génétique des écotypes Grand de cocotier, l’apport des caractères qualitatifs dans l’identification de ces accessions de la collection de Côte d’Ivoire est discuté. Aussi, l’intérêt du recours aux descripteurs qualitatifs comme alternative aux marqueurs moléculaires pour le suivi de la pureté des accessions de cocotier au champ pendant les cycles de régénération est souligné.© 2020 International Formulae Group. All rights reserved. English abstract Qualitative morphological descriptors have always been neglected in coconut population’s characterization, especially in Tall coconut varieties. This paper proposes the contribution of six qualitative traits in the description and typology of 18 Tall coconut populations planted at the international field genebank of Côte d'Ivoire. Relatively to high values of standardized index of Shannon Weaver diversity H' (0.93 to 0.99) and low values of Simpson diversity index D (0.24 to 0.28), the two qualitative traits that are fruit and husked nut shapes were more discriminating. The results about clustering of the Tall coconut populations in Côte d'Ivoire genebank using all studied qualitative characters were in disagreement with the clustering assumed and provided before from quantitative traits and SSRs molecular markers. Although a long time marginalized in the genetic diversity studies, the contribution of the qualitative traits in the identification of Tall coconut populations in international field genebank of Côte d’Ivoire has been discussed. Also, the interest of recourse of the qualitative descriptors as alternative to the molecular markers for purity follow-up of the coconut accession during the cycles of field genebank regeneration is clearly underlined.

Agromorphological diversity structure of the elite shea trees identified in village lands and conserved in situ in the districts of Bagoue and Tchologo by the shea breeding program of the University of Peleforo Gon Coulibaly (UPGC, Cote d’Ivoire), are not known. In the present study, we characterized the agromorphological parameters of 220 elite shea trees using a set of 12 quantitative traits. The results showed that elite shea trees population has been structured into three morphological clusters or genetic pools that do not overlap with the original geographic areas. Morphological Cluster I contain elite shea trees with small trunk diameters carrying large leaves and producing fewer fruits per tree. Morphological Cluster II consisted of elite shea trees with stronger trunks bearing small leaves and producing a high number of fruits per tree. Morphological Cluster III regrouped elite shea trees of medium trunk diameters carrying medium sized leaves; fruit production level is intermediate compare to preceding groups. The elite shea trees of morphological Clusters II, which are more interesting from an agronomic point of view, can be used as grafting trees for the production of high-yielding grafted plants for farmers in Cote d'Ivoire. Key words: elite shea trees, genetic improvement, phenotypic variability, Northern Cote d’Ivoire.

Teak (Tectona grandis L.f; Verbenaceae) is a diploid species (2n=36). It is native to the tropical deciduous forests of India, Myanmar, Thailand and Laos. Snuffed for its aesthetic physical properties and its qualities, teak is becoming increasingly important in the forest plantation development in Côte d'Ivoire. To preserve the genetic resources of this species and ensure the supply of genetically superior quality germplasm for improvement and plantations, a core collection of superior genotypes with large genetic diversity is a prerequisite. This paper reports the use of site-specific recombinase (SSR) technology using microsatellite DNA markers to investigate the level of genetic variability, distribution of genetic variation and genetic relatedness in Tectona grandis grown in Côte d'Ivoire. The proportion of the total genetic variation resides within provenances (80.52 %) with 5.5 % of the variation occurring among populations of one region and 13.98 % among regions. The SSR markers showed a clear differentiation of the populations introduced in Côte d'Ivoire with an Fst = 0.21. The populations coming from the natural area were characterized by three clusters corresponding to South India, North India and Thailand. The study on the origin of African teak was close to North of India. However, Bambuku 7 population was an exception, as it seemed to have some affinity with Thailand populations. The use of SSR markers for conservation of teak forest diversity is discussed.