Medicinal potential, utilization and domestication status of bitter kola (Garcinia kola Heckel) in West and Central Africa

Garcinia kola Heckel (Clusiaceae), known as bitter kola, is a multipurpose tree indigenous to West and Central Africa. This highly preferred species is called wonder plant because all of its parts can be used as medicine. Its seeds, the most valued product of the tree, are commonly eaten to prevent/cure gastric disorders and for their typical astringent taste. There is a vast evidence that bioactive components of the seeds can serve as alternative medicine to treat/prevent severe illnesses such as malaria, hepatitis and immune-destructive diseases. Despite the species' pharmaceutical potential and its high preference by West and Central African communities, G. kola is still at the beginning of its domestication process. Even though, there are numerous scientific articles published on species biological activities, it is a difficult task to find basic information on its diversity, distribution, genetics, silvicultural management or botany. Therefore, in this very first review published on G. kola, we summarize all relevant information known about the species, target some of the challenges connected with its cultivation and propose a leading direction for future research and domestication process

Core Collection Formation in Guatemalan Wild Avocado Germplasm with Phenotypic and SSR Data

Guatemala's wild avocado germplasm holds vital genetic value, but lacking conservation strategies imperils it. Studying its diversity is pivotal for conservation and breeding. The study aimed to comprehensively assess the wild avocado germplasm in Guatemala by combining phenotypic and genotypic data and to create a core collection for conservation and future breeding programs. A total of 189 mature avocado trees were sampled across Guatemala's northern, southern, and western regions. Morphological characteristics were documented, and genetic diversity was assessed using 12 SSR loci. The investigated germplasm revealed three distinct genetic clusters, exhibiting an average gene diversity of 0.796 and a 7.74% molecular variation among them. The samples showed various morphological characteristics that indicate the presence of three avocado races in Guatemala. The weak correlation between phenotypic and genotypic distances highlighted their independence and complementary nature. The joint matrix effectively integrated and captured genotypic and phenotypic data for comprehensive genetic diversity analysis. A core collection comprising 20% of total accessions that captured maximum genetic diversity was formed. This study exposed wild Guatemalan avocados' genetic diversity, morphological traits, and conservation significance. Integrated data capture via clustering validates holistic genetic insight for conservation and breeding strategies

Domestication Potential of Garcinia kola Heckel (Clusiaceae): Searching for Diversity in South Cameroon

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

Variability Analysis of Wild Guatemalan Avocado Germplasm Based on Agro-Morphological Traits

Background. For the Guatemalan culture, the avocado (Persea americana 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. Objective. To explore wild germplasm based on agromorphological characteristics using the standardized descriptors for avocado (Persea spp.). Methodology. 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. Results. 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. Implications. 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. Conclusion. 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

Core Collection Formation in Guatemalan Wild Avocado Germplasm with Phenotypic and SSR Data

Guatemala’s wild avocado germplasm holds vital genetic value, but lacking conservation strategies imperils it. Studying its diversity is pivotal for conservation and breeding. The study aimed to comprehensively assess the wild avocado germplasm in Guatemala by combining phenotypic and genotypic data and to create a core collection for conservation and future breeding programs. A total of 189 mature avocado trees were sampled across Guatemala’s northern, southern, and western regions. Morphological characteristics were documented, and genetic diversity was assessed using 12 SSR loci. The investigated germplasm revealed three distinct genetic clusters, exhibiting an average gene diversity of 0.796 and a 7.74% molecular variation among them. The samples showed various morphological characteristics that indicate the presence of three avocado races in Guatemala. The weak correlation between phenotypic and genotypic distances highlighted their independence and complementary nature. The joint matrix effectively integrated and captured genotypic and phenotypic data for comprehensive genetic diversity analysis. A core collection comprising 20% of total accessions that captured maximum genetic diversity was formed. This study exposed wild Guatemalan avocados’ genetic diversity, morphological traits, and conservation significance. Integrated data capture via clustering validates holistic genetic insight for conservation and breeding strategies

Domestication Potential of <i>Garcinia kola</i> Heckel (Clusiaceae): Searching for Diversity in South Cameroon

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

Domestication Potential of Garcinia kola Heckel (Clusiaceae): Searching for Diversity in South Cameroon

Seeds and bark of Garcinia kola Heckel (Clusiaceae) are popular products in West and Central Africa. Despite the tree&rsquo;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 &ldquo;elite trees&rdquo; 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

Diversity, Chemical Composition, and Domestication Potential of <i>Allanblackia parviflora</i> A. Chev. in West Africa

Allanblackia parviflora A. Chev. is an indigenous tree species which is found in West African rainforest zones. It is an underutilized fruit tree species that has been targeted for improvement as part of efforts to domesticate high-value indigenous multi-purpose trees for fruit and seed production in Africa. Allanblackia has several benefits, such as providing shade, timber, and medicine; however, the production of edible oil from its seeds is the economically most important use. There is evidence that the Allanblackia seed oil, which is used for cooking, the production of margarine and the manufacturing of ointments and soap, is being developed as a new agri-business in Ghana, Nigeria, Cameroon, and Tanzania. Despite the nutritional and socio-economic importance of A. parviflora, it is still at the early stages of its domestication process. Even though several researchers have explored the biology of this species, there is very limited scientific information available on its morphological and genetic diversity and silvicultural management in West Africa. Therefore, this systematic review presents an up-to-date overview on the uses, seed chemical composition, and morphological and genetic diversity of this fruit tree species, and proposes a way forward for future research towards improvement and domestication

Correction: Maňourová et al. Domestication Potential of <i>Garcinia kola</i> Heckel (Clusiaceae): Searching for Diversity in South Cameroon. <i>Plants</i> 2023, <i>12</i>, 742

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VARIABILITY ANALYSIS OF WILD GUATEMALAN AVOCADO GERMPLASM BASED ON AGRO-MORPHOLOGICAL TRAITS

Background. For the Guatemalan culture, the avocado (Persea americana 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. Objective. To explore wild germplasm based on agro-morphological characteristics using the standardized descriptors for avocado (Persea spp.). Methodology. 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. Results. 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. Implications. 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. Conclusion. 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