| Abstract: | Experimental evidence supports the theory that inhibition ofbuds on the under side of horizontal apple branches is causedby the movement under gravity of substances from the upper tothe under sides. Horizontal shoots of apple Crab C were splitalmost to the apex and the two halves separated by a non-porousplastic film. Where upper and lower sides were isolated by theplastic barrier, long shoots grew from the under as well asfrom the upper side. On control shoots, and shoots split vertically,most buds on the under side remained dormant. |
