Genetic Structure and Molecular Diversity of Cacao Plants Established as Local Varieties for More than Two Centuries: The Genetic History of Cacao Plantations in Bahia, Brazil

Author(s)

Santos, Elisa S. L. ^{[1, 2]} ; Cerqueira-Silva, Carlos Bernard M. ^{[1, 2]} ; Mori, Gustavo M. ^[2] ; Ahnert, Dario ^[3] ; Mello, Durval L. N. ^[4] ; Pires, Jose Luis ^[5] ; Correa, Ronan X. ^[3] ; de Souza, Anete P. ^{[2, 6]}

Affiliation

^[1] State Univ Southwest Bahia, Lab Appl Mol Genet, Dept Exact & Nat Sci, Itapetinga, BA - Brazil

^[2] Univ Estadual Campinas, Ctr Mol Biol & Genet Engn, Campinas, SP - Brazil

^[3] Univ Estadual Santa Cruz, Dept Biol Sci, Genet & Biotechnol Ctr, Ilheus, BA - Brazil

^[4] Bahian Fed Inst Educ Sci & Technol, Urucuca, BA - Brazil

^[5] Execut Comm Plan Cacao Farming, Cocoa Res Ctr, Itabuna, BA - Brazil

^[6] Univ Estadual Campinas, Inst Biol, Dept Plant Biol, Campinas, SP - Brazil

• Document type: Journal article
• Source: PLoS One; v. 10, n. 12 DEC 16 2015.
• Web of Science Citations: 6

Abstract

Bahia is the most important cacao-producing state in Brazil, which is currently the sixth-largest country worldwide to produce cacao seeds. In the eighteenth century, the Comum, Para and Maranhao varieties of cacao were introduced into southern Bahia, and their descendants, which are called `Bahian cacao' or local Bahian varieties, have been cultivated for over 200 years. Comum plants have been used to start plantations in African countries and extended as far as countries in South Asia and Oceania. In Brazil, two sets of clones selected from Bahian varieties and their mutants, the Agronomic Institute of East (SIAL) and Bahian Cacao Institute (SIC) series, represent the diversity of Bahian cacao in germplasm banks. Because the genetic diversity of Bahian varieties, which is essential for breeding programs, remains unknown, the objective of this work was to assess the genetic structure and diversity of local Bahian varieties collected from farms and germplasm banks. To this end, 30 simple sequence repeat (SSR) markers were used to genotype 279 cacao plants from germplasm and local farms. The results facilitated the identification of 219 cacao plants of Bahian origin, and 51 of these were SIAL or SIC clones. Bahian cacao showed low genetic diversity. It could be verified that SIC and SIAL clones do not represent the true diversity of Bahian cacao, with the greatest amount of diversity found in cacao trees on the farms. Thus, a core collection to aid in prioritizing the plants to be sampled for Bahian cacao diversity is suggested. These results provide information that can be used to conserve Bahian cacao plants and applied in breeding programs to obtain more productive Bahian cacao with superior quality and tolerance to major diseases in tropical cacao plantations worldwide. (AU)

• FAPESP's process: 08/52197-4 - Genomic-assisted breeding of sugarcane: using molecular markers for understanding the genetic architecture of quantitative traits and to implement marker assisted selection
• Grantee: Anete Pereira de Souza
• Support type: Program for Research on Bioenergy (BIOEN) - Thematic Grants
• FAPESP's process: 13/08086-1 - Population and functional genomics and an ecophysiological approach on the evolutionary study of neotropical mangrove species in face of historical and current climate changes
• Grantee: Gustavo Maruyama Mori
• Support type: Scholarships in Brazil - Post-Doctorate