TY - JOUR
T1 - East Timor as an important source of cashew (Anacardium occidentale L.) genetic diversity
AU - Guterres, Lara Maria Aquino
AU - Barnabé, João
AU - Barros, André
AU - Charrua, Alberto Bento
AU - Duarte, Maria Cristina
AU - Romeiras, Maria M.
AU - Monteiro, Filipa
N1 - Funding Information:
This research was funded by FCT–Fundac¸ão para a Ciência e a Tecnologia, I.P. under the project GenoCash (PTDC/ASP-AGR/0760/2020). Fellowships were funded by Portuguese National Funds through FCT, Portugal: SFRH/BD/135358/2017 to Lara Guterres and SFRH/BD/135360/2017 to Alberto Bento Charrua, and research units: UID/AGR/04129/2020 (LEAF); UID/BIA/00329/2020 (cE3c). The fellowship for João Barnabé was funded by FAO/UN (TCP/GBS/3801). The APC was funded by Fundacão para a Ciência e Tecnologia (FCT) under the GenoCash project (PTDC/ASP-AGR/0760/2020). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Publisher Copyright:
Copyright 2023 Guterres et al.
PY - 2023/4/24
Y1 - 2023/4/24
N2 - Background. Cashew (Anacardium occidentale L.) is a crop currently grown in several tropical countries because of the economic importance of cashew nuts. Despite its enormous economic worth, limited research has been conducted on the molecular diversity of cashew genetic resources. In this study, a wide comprehensive assessment of the genetic diversity of cashew trees in East Timor was performed using microsatellites (SSRs) to evaluate intraspecific diversity and population structuring. Methods. A total of 207 individual cashew trees, including trees from East Timor (11), and outgroup populations from Indonesia (one) and Mozambique (two), were analyzed with 16 cashew-specific SSRs. A comprehensive sampling of cashew trees within East Timor was performed, covering the distribution of cashew orchards in the country. Genetic diversity indices were calculated, and population structuring was determined using three different approaches: genetic distances (UPGMA and NJ), AMOVA, and individual-based clustering methods through Bayesian (STRUCTURE) and multivariate (DAPC) analyses. Results. The population structuring analysis revealed that the genetic diversity of cashew populations in East Timor was higher in this study than previously reported for cashew trees. A higher allelic richness was found within cashew populations in East Timor compared with the outgroup populations (Mozambique and Indonesia), reinforced by the presence of private alleles. Moreover, our study showed that cashew populations in East Timor are grouped into two dissimilar genetic groups, which may suggest multiple cashew introductions over time. These new cashew genetic resources could be explored for future crop improvement. Conclusions. Crop diversity underpins the productivity, resilience, and adaptive capacity of agriculture. Therefore, this study provides useful information regarding genetic diversity and population structure that can be harnessed to improve cashew production in East Timor. This data is also important to creating a country-specific genetic cashew signature to increase cashew market value.
AB - Background. Cashew (Anacardium occidentale L.) is a crop currently grown in several tropical countries because of the economic importance of cashew nuts. Despite its enormous economic worth, limited research has been conducted on the molecular diversity of cashew genetic resources. In this study, a wide comprehensive assessment of the genetic diversity of cashew trees in East Timor was performed using microsatellites (SSRs) to evaluate intraspecific diversity and population structuring. Methods. A total of 207 individual cashew trees, including trees from East Timor (11), and outgroup populations from Indonesia (one) and Mozambique (two), were analyzed with 16 cashew-specific SSRs. A comprehensive sampling of cashew trees within East Timor was performed, covering the distribution of cashew orchards in the country. Genetic diversity indices were calculated, and population structuring was determined using three different approaches: genetic distances (UPGMA and NJ), AMOVA, and individual-based clustering methods through Bayesian (STRUCTURE) and multivariate (DAPC) analyses. Results. The population structuring analysis revealed that the genetic diversity of cashew populations in East Timor was higher in this study than previously reported for cashew trees. A higher allelic richness was found within cashew populations in East Timor compared with the outgroup populations (Mozambique and Indonesia), reinforced by the presence of private alleles. Moreover, our study showed that cashew populations in East Timor are grouped into two dissimilar genetic groups, which may suggest multiple cashew introductions over time. These new cashew genetic resources could be explored for future crop improvement. Conclusions. Crop diversity underpins the productivity, resilience, and adaptive capacity of agriculture. Therefore, this study provides useful information regarding genetic diversity and population structure that can be harnessed to improve cashew production in East Timor. This data is also important to creating a country-specific genetic cashew signature to increase cashew market value.
KW - Genetic diversity
KW - SSRs
KW - Population structuring
KW - Southeast Asia
KW - Diversity hotspots
UR - http://www.scopus.com/inward/record.url?scp=85159200228&partnerID=8YFLogxK
U2 - 10.7717/peerj.14894
DO - 10.7717/peerj.14894
M3 - Article
AN - SCOPUS:85159200228
SN - 2167-8359
VL - 11
JO - PeerJ
JF - PeerJ
M1 - e14894
ER -