Variation in bean morphology and biochemical composition measured in different genetic groups of arabica coffee (Coffea arabica L.)

Abstract

The narrow genetic base of commercial arabica resulting from intensive selection for quality during domestication and self-pollination has been well documented, raising the need for new diverse germplasm sources. Beans of 232 diverse arabica coffee accessions originating from 27 countries were harvested from the germplasm collection at CATIE, Costa Rica. Substantial variation was observed for bean morphology including 100 bean weight, bean length, width, thickness and bulk density. Non-volatiles including caffeine and trigonelline were analysed and showed larger variation in range than has previously been reported. Results of targeted analysis of 18 volatiles from 35 accessions also showed significant variation, with coefficients of variation from 140% for 4-vinylguaiacol to 62% for geraniol. There were strong correlations between some volatile compounds, suggesting that representative volatiles used in selection would save analytical costs. However, no strong correlation was found between bean morphology and the levels of non-volatile or volatile compounds, implying that it is difficult to select for low or high composition of these compounds based on bean physical characteristics. Utilizing the large variation observed for bean morphology and biochemical traits, it should be possible to select for desirable combinations of traits in arabica coffee breeding.

Genome-wide association study reveals candidate genes influencing lipids and diterpenes contents in Coffea arabica L

“…The genetic diversity analysis using SNP markers revealed that the collection of C . arabica used in this study has a higher genetic diversity than traditional cultivars, consistent with the great phenotypic variability observed for the biochemical characterization previously reported 2 , 7 , 12 . In this context, our Ethiopian germplasm collection has been shown to be a valuable source of novel favorable biochemical characteristic-related alleles, which can be explored by breeding programs.…”

“…Although biochemical compounds related to beverage quality traits in coffee, including lipid and diterpene contents 2 , 7 , 12 , have been already described, this is the first large-scale study using an Arabica population that includes several wild accessions from Ethiopia. Accessions with different lipid and diterpene contents may serve as a source of alleles for the development of plants with desirable lipid and diterpene contents in the beans.…”

“…Overall, our results can help us to define which accessions are more important to preserve in order to have a good genetic representation of the FAO collection. The genetic diversity of plants from the western region demonstrated the importance of carefully preserving and exploring the accessions from this region in order to increase genetic variability, especially for coffee beverage quality 12 . It is important to observe that our work was performed only with a subset of the full FAO collection.…”

“…The accessions available in this collection show great phenotypic variation in plant architecture, and size of branches, leaves, fruits, and seeds. In relation to biotic and abiotic factors, these coffee accessions exhibit various levels of tolerance and resistance 11 , 12 . In addition to these morphological and agronomical characteristics, these accessions present a large variability in terms of biochemical contents in green beans, which often translates into a large range of beverage qualities 2 , 12 , 13 .…”

G × E interactions on yield and quality in Coffea arabica: new F1 hybrids outperform American cultivars

“…However, The W100 is widely used for other crops. For coffee, this measurement is used in some studies where it appears to be representative of the bean density and therefore of the quality of seed filling during the development and ripening of the fruit (Bertrand et al 2005;Tran et al 2017). Here, we studied the bean size and the weight of 100 healthy green beans.…”