Revealing the Diversity of Introduced Coffea canephora Germplasm in Ecuador: Towards a National Strategy to Improve Robusta

Abstract

Genetic resources of Coffea canephora have been introduced in several tropical countries with potential for crop development. In Ecuador, the species has been cultivated since the mid-20th century. However, little is known about the diversity and genetic structure of introduced germplasm. This paper provides an overview of the genetic and phenotypic diversity of C. canephora in Ecuador and some proposals for implementing a breeding program. Twelve SSR markers were used to analyze 1491 plants of C. canephora grown in different living collections in Ecuador, compared to 29 genotypes representing the main genetic and geographic diversity groups identified within the species. Results indicated that most of the genotypes introduced are of Congolese origin, with accessions from both main subgroups, SG1 and SG2. Some genotypes were classed as hybrids between both subgroups. Substantial phenotypic diversity was also found, and correlations were observed with genetic diversity. Ecuadorian Robusta coffee displays wide genetic diversity and we propose some ways of improving Robusta in Ecuador. A breeding program could be based on three operations: the choice of elite clones, the introduction of new material from other countries (Ivory Coast, Uganda), and the creation of new hybrid material using genotypes from the different diversity groups.

Postharvest effects on the physical quality and sensory characteristics of Coffea canephora

“…Originating from Costa Rica and falling within the "Robusta" category (with a genetic group referred to as putative SG2), this genetic material gradually extended its presence to several coastal provinces and the northern areas of the Ecuadorian Amazon. Subsequently, in 1987, Ecuador imported genetic material of the "Conilon" type (putative SG1) from Brazil (Leroy et al, 2014;Loor Solórzano et al, 2017). In Ecuador, scientists developed a breeding program to improve C. canephora coffee plants.…”

Genetic Diversity and Population Structure Analysis of Coffee (Coffea canephora) Germplasm Collections in Indian Gene Bank Employing SRAP and SCoT Markers

“…The genetic diversity of C. canephora accessions has been analyzed using different markers such as Restriction fragment length polymorphism (RFLP) (Gomez et al, 2009), Amplified fragment length polymorphism (AFLP) (Prakash et al, 2005), Random amplified Polymorphic DNA (RAPD) and Inter simple sequence Repeats (ISSR) (Tshilenge et al, 2009), Simple sequence repeats (SSR) (Leroy et al, 2014;Ogutu et al, 2016) and Single nucleotide polymorphism (SNP) (Anagbogu et al, 2019). Interestingly, during the last three years, there was a renewed interest in the molecular-based genetic diversity analysis of C. canephora population in many coffee growing countries which include Brazil (Bikila et al, 2017), Vietnam and Mexico (Garavito et al, 2016), Kenya (Ogutu et al, 2016), Ecuador (Solorzano et al, 2017)and Nigeria (Anagbogu et al, 2019). In past, the genetic diversity analysis of Indian robusta gene pool was analyzed using limited number of SSR and AFLP markers (Prakash et al, 2005).…”