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Seeds and bark of Garcinia kola Heckel (Clusiaceae) are popular products in West and Central Africa. Despite the tree’s economic and cultural importance, little is known about its phenotypic and genotypic variation. This study characterised the morphological and genetic diversity of G. kola in South Cameroon, searching for traits and populations that might be used for domestication. Morphological assessment and amplified fragment length polymorphism (AFLP) markers were applied to characterise diversity among geographic populations from Central and South regions, and between managed and wild trees. AFLP-SURV and analysis of molecular variance results indicated that a major part of genetic diversity is harboured within populations rather than between them. Bayesian analysis, principal component analysis and t-SNE identified three clusters where Ebolowa emerged as the transition population combining features from both regions. Trees from the South demonstrated a higher incidence of domestication-related traits, showing higher genetic diversity compared to the Central region. This suggests that individuals from the South might be more suitable for selection as “elite trees” in future breeding strategies for the species. No significant differences in phenotype and genotype were revealed between wild and managed populations, suggesting G. kola is still in the early stages of its domestication process.

<p><strong>Background. </strong>For the Guatemalan culture, the avocado (<em>Persea americana</em> Mill) represents more than a crop, since it has religious, mythical, economical, and medicinal significance typical of the center of domestication of the species. Although there is speculation about the wide variability of wild avocado germplasm, there are no studies describing avocado populations. <strong>Objective.</strong> To explore wild germplasm based on agro-morphological characteristics using the standardized descriptors for avocado (<em>Persea</em> spp.). <strong>Methodology. </strong>The distribution of characteristics of 189 avocado trees across eight populations was evaluated using cross-tabulation and Chi-square testing. In order to properly handle qualitative and quantitative data, it was employed the factor analysis of mixed data (FAMD) and hierarchical clustering on principal components (HCPC) to analyze the relationship and variation of features within and between populations. <strong>Results.</strong> The samples showed various morphological characteristics that indicate the presence of Mexican, Guatemalan, and West Indian avocado races in Guatemala. The FAMD revealed that the fruit shape, skin color and flesh texture, and anise odor in the leaves are ideal traits for distinguishing between individual trees. At the population level, the HCPC showed considerable variance amongst the studied trees but no distinct geographic groups of the samples. <strong>Implications.</strong> Although not all wild avocados grown in Guatemala are of the highest quality, several trees of extraordinary excellence are strewn over the republic's highlands. Thus, due to the danger posed by the introduction of commercial varieties, it is advisable preserving the germplasm. <strong>Conclusion. </strong>The clustering methods revealed that the 189 avocado trees could be regrouped into three main clusters. The morphological descriptors proved to be useful for grouping trees according to known races and can therefore be used in the characterization of cultivars and wild trees whose ancestry is unknown.</p>

Even though Guatemala is considered one of the three domestication centres of the avocado (Persea americana Mill), little is known about the genetic diversity of its native populations. This is the first study to explore avocado genetic diversity and population structure in native dispersal areas using microsatellite markers. We sampled 189 avocado trees grown from seeds in eight geographical populations, and 12 microsatellite loci were tested for diversity. There were a total of 289 alleles found throughout the 12 loci, with an average of 23.83 alleles per locus. The average observed and expected heterozygosity were 0.53 and 0.83, respectively. The analysis of molecular variance revealed that the eight populations comprised around 2% of the variation. Five of the 28 G'ST(Nei) pairwise comparisons indicated no genetic difference. We discovered a mixture of avocado trees from various populations using unweighted pair group method with arithmetic mean (UPGMA) hierarchical cluster analysis. The sampled individuals were classified into three main genetic clusters by the model-based STRUCTURE and discriminant analysis of principal components (DAPC). The weak genetic structure exhibited by mixing avocado trees from different populations could be mainly attributed to high human-mediated gene flow (Nm = 12.25) due to avocado's importance in food, culture, and Guatemala's religion. The high genetic diversity found in the avocado germplasm suggests that it might be a valuable source of variable alleles that could be used in breeding programs for this crop in Guatemala.