FOLIAR AND SOIL APPLICATION OF PACLOBUTRAZOL ON GLOSTER APPLE

Foliar and soil treatments of Paclobutrazol on young Gloster apple trees/M26 are reported.
The former were applied 3 times in 1983 and once in 1984 at two rates, the latter in the fall of 1983, replicated at the beginning of 1985, at two rates.

Both treatment regimes mainly suppressed shoot elongation in the second year (1984), although foliar sprays were less effective the first year allowing a growth return after June.
Internode length was shorter and treated leaves were smaller, with higher specific dry matter, chlorophyll, N, Ca and Mg contents.
P was not significant and K slightly lower than control.

Only foliar sprays enhanced fruit bud differentiation and yield in the second year (bearing index over 50%), with minimal negative effects on fruit size and skin color.
The soil drenches either did not affect fruit quality or slightly improved it in the first year.

V International Symposium on Growth Regulators in Fruit Production

S. Sansavini, R. Bonomo, A. Finotti, U. Palara

https://doi.org/10.17660/ActaHortic.1986.179.75