Cl. Ky et al., Trigonelline inheritance in the interspecific Coffea pseudozanguebariae x C-liberica var. dewevrei cross, THEOR A GEN, 102(4), 2001, pp. 630-634
Trigonelline alkaloid is present in coffee beans, and during roasting it gi
ves rise to the major coffee aroma compounds (several alkyl-pyridines and p
yrroles). In this study we investigated the genetic inheritance of trigonel
line accumulation in green beans in an interspecific cross between a wild e
ast African species, Coffea pseudozanguebariae (PSE) and the west African s
pecies C. liberica var. dewevrei (DEW). Trigonelline content was measured b
y HPLC in both parental species, F-1 hybrids and the reciprocal backcross h
ybrids (BCDEW and BCPSE). The results showed that, on average, PSE accumula
ted twice as much trigonelline as DEW. No year effect or interaction (genot
ype x year) was recorded. Trigonelline showed high heritability (71%), whic
h meant that the genotypic value could be easily estimated from the phenoty
pic value. However, the fact that this trait was not additive suggested the
possibility of nucleo-cytoplasmic inheritance. This hypothesis was confirm
ed by: (1) similar levels of trigonelline content in the PSE, Fl, BCPSE and
BCDEW groups, all having the same maternal cytoplasm, and (2) the location
of one nuclear QTL on the G linkage group.