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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.

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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.

This study compared different methods of determining starch digestibility (in vivo vs in vitro) in wheat grains and evaluated the influence of extrusion on digestibility. In vivo starch digestibility was determined in broiler chickens by calculating the residual starch content in their ilea and the digestibility using a chromium oxide indicator. In vitro digestibility was examined using pepsin and pancreatin. During in vivo testing, the highest digestibility coefficient (DC) was achieved by the Bonanza variety in its extruded form (91.19 ± 0.40%). In contrast, the lowest DC was achieved by the Tobak variety in its non-extruded form (81.45 ± 1.92%). Generally, a higher DC was observed in vivo for extruded forms of wheat. During in vitro testing, the highest DC was achieved by the Stefii variety in its non-extruded form (96.10 ± 0.55%), whereas the lowest DC was observed in the Yetti variety in its extruded form (49.72 ± 0.41%). Overall, the in vitro experiments did not exhibit significant differences between extruded and non-extruded forms of wheat. Linear regression analysis showed a strong relationship (r2 = 0.860; 85.98%) between in vivo- and in vitro-derived DC values in all wheat varieties, both in extruded and non-extruded forms. The study showed that in vivo testing is a suitable method for the determination and control of starch levels in extruded materials. However, despite the accuracy of this technique, it is also very demanding in terms of time, space, equipment, and methodological knowledge. Therefore, based on the strong correlation between the in vivo and in vitro assays, we recommend in vitro digestibility testing as a preferable alternative.

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.

Currently, the negative effects of unified and intensive agriculture are of growing concern. To mitigate them, the possibilities of using local but nowadays underused crop for food production should be more thoroughly investigated and promoted. The soybean is the major crop cultivated for vegetable oil production in Zambia, while the oil production from local oil-bearing plants is neglected. The chemical composition of oils and cakes of a three traditional oil plant used by descendants of the Lozi people for cooking were investigated. Parinari curatellifolia and Schinziophyton rautanenii oils were chiefly composed of α-eleostearic (28.58–55.96%), linoleic (9.78–40.18%), and oleic acid (15.26–24.07%), whereas Ochna serrulata contained mainly palmitic (35.62–37.31%), oleic (37.31–46.80%), and linoleic acid (10.61–18.66%); the oil yield was high (39–71%). S. rautanenii and O. serrulata oils were rich in γ-tocopherol (3236.18 μg/g, 361.11 μg/g, respectively). The O. serrulata oil also had a very distinctive aroma predominantly composed of p-cymene (52.26%), m-xylene (9.63%), γ-terpinene (9.07%), o-xylene (7.97), and limonene (7.23%). The cakes remaining after oil extraction are a good source of essential minerals, being rich in N, P, S, K, Ca, and Mg. These plants have the potential to be introduced for use in the food, technical, or pharmaceutical industries.