ROOTSTOCK EFFECTS ON THE RESPONSE OF COX'S ORANGE PIPPIN APPLE TO FRUIT-SETTING HORMONE SPRAYS OF GA3, DPU AND EITHER NAA OR NOXA

J.E. Jackson, A.B. Blasco, S.M. El Senfaz
Spraying open-pollinated trees of Cox's Orange Pippin apple on M.9 rootstock at 80% petal-fall with GA3, DPU and either NAA or NOXA in a 3-component mixture increased both initial and final fruit set. The same treatments applied to Cox trees on M.26, M.7 and MM.106, randomised with the trees on M.9 in the same field experiment, gave increases in initial set but had no effects on final set. The difference in Cox response on the different rootstocks appears to be linked to the greater ability of trees on M.9 to retain seedless or few-seeded fruits: it may provide an explanation for the contrasting effects of fruit-setting sprays on Cox which have been reported by different research workers.
Jackson, J.E., Blasco, A.B. and El Senfaz, S.M. (1983). ROOTSTOCK EFFECTS ON THE RESPONSE OF COX'S ORANGE PIPPIN APPLE TO FRUIT-SETTING HORMONE SPRAYS OF GA3, DPU AND EITHER NAA OR NOXA. Acta Hortic. 137, 261-268
DOI: 10.17660/ActaHortic.1983.137.29
https://doi.org/10.17660/ActaHortic.1983.137.29

Acta Horticulturae