TAKEO SUZUKI: Lateral bud-burst and shoot growth in horizontally trained stems of low-pruned mulberry plants (Morus alba L.). Training of 1-year-old stems (coppiced shoots) of low-pruned stumps of mulberry (Morus alba L, cv. Shin-ichinose) horizontally (arching) before spring bud-burst resulted in a remarkable inhibition of the development of buds on the abaxial (lower) side which remained dormant or grew only into spur buds or poor short shoots. On the other hand, some of the buds (basal ones)

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... on the abaxial (upper) side grew into leading shoots. This inhibitory effect was found to be a gravimorphic one, by the removal of the buds on the upper (or upper and lateral) side (s) of the arched stems (disbudding) before spring budburst. Thus in these disbudded, arched stems, there was a delay in the sprouting of the buds on the lower side as in the case of the buds on the lower side of the untreated arched stems. The effects of arching applied during sprouting and the beginning of elongation of the new sprouts on bud activity and shoot length were generally similar to those of earlier arching before spring bud-burst. However, the removal of the buds on the upper (and also lateral) side (s) of the arched stems during sprouting or the excision of the new sprouts on the upper (and also lateral) side(s) at the onset of new shoot elongation somehow alleviated the inhibition of elongation of the sprouts and shoots from the lower side. Sprouted buds (new sprouts) on the lower side of the arched stem thus appeared to be inhibited by gravitional effects, including effects mediated through components translocated from the new shoot growth on the upper and lateral sides.