Preliminary Evidence for Domestication Effects on the Genetic Diversity of Guazuma crinita in the Peruvian Amazon

Abstract

Guazuma crinita, a fast-growing timber tree species, was chosen for domestication in the Peruvian Amazon because it can be harvested at an early age and it contributes to the livelihood of local farmers. Although it is in an early stage of domestication, we do not know the impact of the domestication process on its genetic resources. Amplified fragment length polymorphic (AFLP) fingerprints were used to estimate the genetic diversity of G. crinita populations in different stages of domestication. Our objectives were (i) to estimate the level of genetic diversity in G. crinita using AFLP markers, (ii) to describe how the genetic diversity is distributed within and among populations and provenances, and (iii) to assess the genetic diversity in naturally regenerated, cultivated and semi-domesticated populations. We generated fingerprints for 58 leaf samples representing eight provenances and the three population types. We used seven selective primer combinations. A total of 171 fragments were amplified with 99.4% polymorphism at the species level. Nei’s genetic diversity and Shannon information index were slightly higher in the naturally regenerated population than in the cultivated and semi-domesticated populations (He = 0.10, 0.09 and 0.09; I = 0.19, 0.15 and 0.16, respectively). The analysis of molecular variation showed higher genetic diversity within rather than among provenances (84% and 4%, respectively). Cluster analysis (unweighted pair group method with arithmetic mean) and principal coordinate analysis did not show correspondence between genetic and geographic distance. There was significant genetic differentiation among population types (Fst = 0.12 at p ˂ 0.001). The sample size was small, so the results are considered as preliminary, pending further research with larger sample sizes. Nevertheless, these results suggest that domestication has a slight but significant effect on the diversity levels of G. crinita and this should be considered when planning a domestication program.

Genetic Diversity and Population Structure of Capirona (<em>Calycophyllum spruceanum</em> Benth.) from the Peruvian Amazon Assessed by RAPD Markers

“…In addition, this is expected in this species, because it produces seeds that are dispersed over long distances by wind and water. In general, this is the case of tropical trees, and especially those that are outcrossing, and pollinated and/or dispersed by wind, so they tend to harbor high levels of genetic diversity at local and regional spatial scales [24]. Moreover, our results are in agreement with similar studies by Russell et al [1] and Tauchen et al [3].…”

“…Thus, although genetic relationship between species is relatively low using those markers (low Nei´s index), the diversity of the sequences and therefore of the population is relatively high (high Simpson and Shannon indices) [22,23]. Similarly, a recent study on Guazuma crinita reported low Nei´s gene diversity and high Shannon information index [24]. In addition, our expected heterozygosity is similar to the populations of tornillo (Cedrelinga cateniformis) [16].…”

“…To our best knowledge, this is the first study that employs molecular markers to estimate population structure and genetic diversity of capirona from a wide range of natural distribution in Peru. Molecular markers based on DNA (RAPD, AFLP, SSRs) are used to study genetic variation in forest species [1,8,19,24]. Advantages of these methods over others include their better representation of the variation present within species [12].…”

Genetic Diversity and Population Structure of Capirona (Calycophyllum spruceanum Benth.) from the Peruvian Amazon Revealed by RAPD Markers

“…Nei's genetic diversity index ranged from 0.12 to 0.41, indicating high genetic diversity, which is concordant for specimens from natural populations as they are not affected by artificial selection. Maintaining high genetic diversity in natural populations is important because it reduces the risk of local extinction under natural conditions [50,51]. Similarly, the Shannon-Wiener index is slightly high (1.79 to 2.94) and demonstrates the wealth and abundance among capirona clusters.…”

Allometric models to estimate the volume of Guazuma crinitain forest plantations

“…Bolaina blanca (Guazuma crinita Mart, Meliaceae) es una especie forestal maderable de rápido crecimiento que se desarrolla en bosques aluviales de la Amazonía Peruana (Tuisima-Coral et al, 2020). Posee excelentes propiedades físicas, mecánicas y estéticas, razón por la cual viene siendo utilizada en la obtención de madera rolliza y aserrada para la fabricación de parihuelas, cajonería, laminado, juguetería, palos de fósforo, paletas de consultorios médicos, chupetes, palitos de helados, artesanía, tableros contrachapados, entre otros (IIAP, 2009;Basauri et al, 2019).…”