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S U M M A R YThe auxin-transport-inhibiting morphactin chlorflurenolmethylester (CFM; Methyl 2-chloro-9-hydroxyfluorene-9-carboxylate) breaks the dormancy of axillary buds in young coffee plants and produces orthotropic shoots. A concentration of CFM as low as 50 mg/litre induced an average of 24 orthotropic shoots per 6-month-old seedling. This approach could provide a fast and inexpensive method of vegetative propagation for raising disease-resistant cultivars if adult clones respond similarly to the seedlings used here and the treatment does not adversely affect the propagation of induced shoots.The hybrid nature of new cultivars of Coffee arabica L. resistant to coffee berry disease (Colletotrichum coffeanum Noack) and coffee leaf rust (Hemileia vastatrix Berk and br.) requires vegetative propagation to maintain the desirable characteristics of the original selections and to establish uniform plantations (Van der Vossen et al., 1977).Only orthotropic (upright-growing) shoots can be used in propagating coffee by cuttings or grafting, but orthotropic shoots can produce both ortho-and plagiotropic (horizontal-growing) branches; cuttings or grafts taken from the latter, however, cannot produce orthotropic branches and do not show normal vertical growth. Grafting nevertheless offers the advantage that existing coffee plantations can be converted to the new disease-resistant clonal material without the need for replanting (Van der Vossen et al.).Each leaf-axil on orthotropic shoots of coffee has a single extra-axillary 'head of series' bud, which can form a plagiotropic shoot. There are also four to six axillary buds, which can usually produce orthotropic shoots or, occasionally, an inflorescence, but are inhibited from doing so by apical dominance (Meyer, 1939;Moens, 1963;Wormer and Gituanja, 1970). Removal of the auxin-producing apex of an orthotropic shoot breaks apical dominance to the extent that only the topmost node now produces two (orthotropic) branches, one on each side. The apices of these newly-formed orthotropic shoots become dominant in turn, inhibiting buds on their lower nodes (Fig. 1), which explains why young coffee plants have very few upright shoots and can only be increased very slowly by vegetative multiplication.It currently takes many years for a single selected plant to be propagated