Structure and genetic diversity in wild and cultivated populations of Zapote mamey (Pouteria sapota, Sapotaceae) from southeastern Mexico: its putative domestication center

Tropical fruit trees are an important component of the human diet; however, little is known about their genetic diversity levels. Zapote mamey (Pouteria sapota) is a tree native to southeastern Mexico and Central America, and Mexico is the leading producer in the world. Studies of the genetic diversity of Zapote mamey have been based on cultivated materials using morphological and biochemical characterization or dominant molecular markers. To gain a deeper understanding about the conservation status of Zapote mamey in its center of origin and domestication, we collected 188 individuals from eight wild and five cultivated populations in southeastern Mexico and characterized them using eight microsatellite loci. STRUCTURE, 3D-PCoA, and neighbor-joining analyses showed three groups in the wild gene pool and one group in the cultivated gene pool. FST values were significant between wild and cultivated gene pools, among the four groups observed and among the 13 populations collected (0.13, 0.25, and 0.36, respectively). Overall, we found low levels of genetic diversity (A = 2.77, HO = 0.29, HE = 0.39), permutation tests did not show significant differences between wild and cultivated gene pools. The Garza–Williamson index showed low values in both gene pools (wild = 0.16, cultivated = 0.11) and the Bottleneck program indicated a decrease in genetic diversity in both gene pools (wild, P = 0.027; cultivated, P = 0.054); both analyses suggest a potential genetic bottleneck within this species. This study can help to generate adequate sampling techniques and to develop effective management strategies for Zapote mamey of southeastern Mexico

Structure and genetic diversity in wild and cultivated populations of Zapote mamey (Pouteria sapota, Sapotaceae) from southeastern Mexico: its putative domestication center

Tropical fruit trees are an important component of the human diet; however, little is known about their genetic diversity levels. Zapote mamey (Pouteria sapota) is a tree native to southeastern Mexico and Central America, and Mexico is the leading producer in the world. Studies of the genetic diversity of Zapote mamey have been based on cultivated materials using morphological and biochemical characterization or dominant molecular markers. To gain a deeper understanding about the conservation status of Zapote mamey in its center of origin and domestication, we collected 188 individuals from eight wild and five cultivated populations in southeastern Mexico and characterized them using eight microsatellite loci. STRUCTURE, 3D-PCoA, and neighbor-joining analyses showed three groups in the wild gene pool and one group in the cultivated gene pool. FST values were significant between wild and cultivated gene pools, among the four groups observed and among the 13 populations collected (0.13, 0.25, and 0.36, respectively). Overall, we found low levels of genetic diversity (A = 2.77, HO = 0.29, HE = 0.39), permutation tests did not show significant differences between wild and cultivated gene pools. The Garza–Williamson index showed low values in both gene pools (wild = 0.16, cultivated = 0.11) and the Bottleneck program indicated a decrease in genetic diversity in both gene pools (wild, P = 0.027; cultivated, P = 0.054); both analyses suggest a potential genetic bottleneck within this species. This study can help to generate adequate sampling techniques and to develop effective management strategies for Zapote mamey of southeastern Mexico

Characterization of mamey [Pouteria sapota (Jacq.) Moore & Stearn] in the Totonacapan Poblano region of Puebla, Mexico

Abstract The mamey is a fruit tree that is distributed in the Totonacapan Poblano, which has the potential to generate development in that region. It is part of an environmental ecological system that presents morphological variations in size, leaves and fruit. The objective of this study was to morphologically characterize the mamey in 10 municipalities of the Sierra Nororiental of Puebla (Totonacapan Poblano), Mexico. 206 samples were evaluated using qualitative and quantitative morphological descriptors, using principal component analysis and cluster analysis. Eight groups were formed; the tree and leaf variables turned out to be the most important for grouping the samples. The descriptors that contributed the most to the group were those related to the shape, height and size of the tree, the weight, size and shape of the leaf and in relation to the fruit the descriptor that contributed the most was the shape. Keywords: morphological diversity, conglomerates, Sierra Norte of Puebla, Sapotaceae.Objective: The objective of this study was to morphologically characterize mamey in 10 municipalities of the Sierra Nororiental of Puebla (Totonacapan Poblano), Mexico. Design/methodology/approach: In the study, 206 accessions obtained from simple random sampling using qualitative and quantitative morphological descriptors were evaluated, using an analysis of variance, principal components and hierarchical cluster analysis with the Gower distance and the Ward grouping method. Results: Quantitative descriptors had high coefficients of variability (12.66% to 43.40%). The principal components analysis indicated that components 1 (41.66%), 2 (19.97%) and 3 (16.62%) accounted for 78.25% of the variance and the cluster analysis identified eight groups; the tree and leaf variables turned out to be the most important to group the samples. Limitations on study/implications: For greater accuracy on the morphological diversity of mamey, it is necessary to include more descriptors of the fruit and the flower. Findings/conclusions: The descriptors that contributed the most to the grouping were those related to the shape, height and size of the tree, and the weight, size and shape of the leaf; in relation to the fruit, the descriptor that contributed the most was the shape. These results could be useful in programs of conservation, improvement, and use of the mamey