Ploidy level and caffeine content in leaves of Coffea

Abstract

Several species of Coffea and varieties of C. arabica differing in chromosome number had their caffeine content determined in the leaves. For Coffea arabica var. "Angustifolia", var. "Caturra" and var. "Icatu", it was observed caffeine decrease from the haploid (2n = 22) to tetraploid leaves (2n = 44). Caffeine in the tetraploid "Angustifolia" was decreased by 50% when compared to the haploid. Caffeine reduction was also observed in leaves of C. canephora var. "Kouilou" as chromosome number was increased (2n = 22 ® 2n = 44). In this case, caffeine in the leaves of the diploid genotype was close to 4 times higher than in the tetraploid. On the other hand it was observed an increase of the alkaloid when the chromosome number was doubled in the C. canephora var. "Robusta".

Caffeine inheritance in interspecific hybrids of Coffea arabica x Coffea canephora (Gentianales, Rubiaceae)

“…However, the highest caffeine content in leaves occurred in the BV parent and not in the R4x parent, as was the case for seed caffeine content. Previous studies have shown similar values for caffeine in the leaves C. arabica used as P 1 (i.e., 1%: Mazzafera and Magalhães, 1991) and C. canephora R4x used as P 2 (i.e., 0.21%: Silvarolla et al, 1999). In our study, the occurrence of plants transgressive for caffeine in leaves indicate that the parents probably have major and minor genes for caffeine production.…”

“…Dewevrei and the caffeine-free wild species Coffea pseudozanguebariae and proposed that the absence of caffeine was controlled by cc alleles. Interestingly, the caffeine content of coffee seeds and leaves seems to be independently controlled (Mazzafera and Magalhães, 1991), with, in general, the caffeine content of leaves being lower than that of seeds even in coffee species with duplicated chromosome numbers (Silvarolla et al, 1999).…”

Characterisation of AC1: a naturally decaffeinated coffee

“…Currently, the only commercially available decaffeinated beans are those that have been artificially treated using chemical processes. The drawback of chemical decaffeination methods is that, along with the removal of caffeine, there are also losses of or changes to important chemical compounds that contribute to the flavour and aroma of the beverage (Farah et al, 2006a,b;Toci et al, 2006;Abrahão et al, 2008). In an attempt to meet the demands of customers sensitive to caffeine while maintaining the original quality of a coffee product, studies have focused on the selection and breeding of coffee trees that produce beans with a low caffeine content, which would therefore not require chemical processing methods (Mazzafera et al, 2009).…”

“…In 1987, the Agronomic Institute of Campinas established a breeding program to reduce the caffeine content in Arabica coffee beans (Mazzafera and Carvalho, 1992;Mazzafera et al, 1997;Silvarolla et al, 1999;2000). As part of this program, analysis was performed on the alkaloids from C. arabica accessions from Ethiopia and maintained in the germplasm collection of the IAC (Silvarolla et al, 2000;.…”

“…As part of this program, analysis was performed on the alkaloids from C. arabica accessions from Ethiopia and maintained in the germplasm collection of the IAC (Silvarolla et al, 2000;. Among more than 3,000 trees representing 300 accessions, three plants were discovered whose beans had very low concentrations of caffeine, and these plants were named AC1, AC2 and AC3 (Silvarolla et al, 2004). The AC1 plant was the most suitable candidate for the genetic transferral of the "no caffeine" trait to cultivars with high productivity (M.B.…”