Publications des agents du Cirad

Cirad

Soluble sugars, enzymatic activities and gene expression during development of coffee fruits submitted to shade condition

Marraccini P., Geromel C., Ferreira L.P., Perreira L.F.P., Leroy T., Pot D., Davrieux F., Ribeyre F., Guyot B., Scholz M.B.D.S., Androcioli Filho A., Vieira L.G.E., Mazzafera P.. 2007. In : 21st International Conference on Coffee Science, Montpellier (France), 11th - 15th September 2006. Montpellier : ASIC, p. 673-678. Colloque Scientifique International sur le Café. 21, 2006-09-11/2006-09-15, Montpellier (France).

Effects of shade (50% light) condition on development and sugar metabolism was analyzed in fruits of Coffea arabica L. var. IAPAR 59. Fresh weight measurements of separated tissues (pericarp, perisperm and endosperm) showed that the increased size observed in beans of shaded plants was correlated with high perisperm development. Reducing sugar contents in the pericarp and endosperm of fruits from shaded plants appeared higher than in the same tissues of control ("full-sun") plants. On the contrary, sucrose content was slightly lower in shade than in control beans. At the enzymatic level, sucrose synthase activities detected in the latest stages (197-231 DAF) of perisperm development from shaded plants were higher than from of control, confirming the importance of this tissue in coffee fruit development. At the molecular level, the CaSUS1 and CaSUS2 gene expression was also analyzed in the endosperm from control and shaded fruits. Expression level of CaSUS2 was higher in mature beans (260 DAF) of shaded plants than in control plants (231 DAF). These results showed that light condition affect sucrose metabolism of coffee beans.

Mots-clés : coffea arabica; métabolisme des glucides; développement biologique; fruit; teneur en glucides; ombrage; ligase; activité enzymatique; saccharose; saccharose synthétase

Documents associés

Communication de congrès

Agents Cirad, auteurs de cette publication :