MINIMAL GROWTH-INVITRO CONSERVATION OF COFFEE (COFFEA SPP) .1. INFLUENCE OF LOW CONCENTRATIONS OF 6-BENZYLADENINE

We have studied the influence of low concentrations of 6-benzyladenine on growth limitation, in order to preserve coffee germplasm through a microcutting collection. Concentrations of 0-mu-M, 1.3-mu-M and 4.4-mu-M were compared in four species: Coffea congensis, C. canephora, C. liberica and C. racemosa. After six months, microcutting behaviour varied between the different treatments, and a species effect was observed. The slow growing species (C. liberica and C. congensis) needed 1.3-mu-M; the others coffee species (C. canephora and C. racemosa) exhibited moderate caulogenesis on 6-benzyladenine-free medium. Zero and low concentrations did not affect survival rates. In conclusion 1.3-mu-M seems most appropriate for conserving all four species.