Abstract
The induction of parthenocarpic fruit set was investigated using the apple cvs. Golden Delicious and Jonagold. The gibberellins GA3, GA4, GA5 and GA7 and the synthetic phenylurea-type cytokinin CPPU (N-(2-chloro-4-pyridyl)-N-phenylurea), were applied alone and in combination to unpollinated flowers at the end of petal fall. Gibberellins induced only a marginal final set of parthenocarpic fruits. CPPU sprays were more effective, particularly in the first year. When applied in combination, CPPU and gibberellins had a positive synergistic effect on parthenocarpic fruit set and fruit size, but a negative effect on flower induction the next year. After CPPU + GA sprays, percent fruit set was similar, or greater, compared to natural pollinated trees. The parthenocarpic fruits induced by CPPU + GA had an increased length to diameter ratio. CPPU stimulated, and GA4 and GA7 reduced, the russeting of the parthenocarpic fruits. The internal quality of the fruits was hardly affected, but Ca-deficiency symptoms occurred more frequently in parthenocarpic fruits.
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References
Bangerth F (1979) Calcium related physiological disorders of plants. Ann Rev Phytopathol 17: 97–122
Bangerth F (1989) Dominance among fruits/sinks and the search for a correlative signal. Physiol Plant 76: 608–614
Banuelos GS, Bangerth F and Marschner H (1987) Relationship between polar basipetal auxin transport and acropetal Ca transport into tomato fruits. Physiol Plant 71: 321–327
Bohner J and Bangerth F (1988) Cell number, cell size and hormone levels in semi-isogenic mutants of Lycopersicon pimpinellifolium differing in fruit size. Physiol Plant 72: 316–320
Browning G (1989) The physiology of fruit set. In: Wright CJ (ed) Manipulation of Fruiting, pp 195–217. London: Butterworths
Buban T and Faust M (1982) Flower bud induction in apple trees: internal control and differentiation. Hortic Rev 4: 174–203
Bukovac MJ and Nakagawa S (1967) Comparative potency of gibberellins in inducing parthenocarpic fruit growth in Malus sylverstris Mill. Experientia 23: 865–867
Bünger-Kibler S and Bangerth F (1983) Relationship between cell number, cell size and fruit size of seeded fruits of tomato and those induced parthenocarpically by the application of plant growth regulators. Plant Growth Reg 1: 143–154
Chan RG and Cain JC (1967) The effect of seed formation on subsequent flowering. Proc Am Soc Hort Sci 91: 63–68
Curry EA and Green DW (1993) CPPU influences fruit quality, fruit set, return bloom, and preharvest drop of apples. Hort Science 28: 115–119
Davison RM (1960) Fruit-setting of apples using gibberellic acid. Nature 188: 681–682
Dennis FG (1973) Physiological control of fruit set and development with growth regulators. Acta Hortic 34: 251–259
Dennis FG (1986) Apple. In: monselise SP (ed) CRC Handbook of Fruit Set and Development, pp 1–44. Boca Raton, Florida. CRC Press
Goldwin GK (1992) Environmental and internal regulation of fruiting, with particular reference to Cox's Orange Pippin apple. In: Marshall C and Grace J (eds) Fruit and Seed Production, pp 75–100. Cambridge: Cambridge University Press
Green DW (1989) CPPU influences McIntosh apple crop load and fruit characteristics. Hort Science 24: 94–96
Gustafson FG (1936) Inducement of fruit development by growth promoting chemicals. Proc Natl Acad Sci USA 22: 628–636
Hoad GV (1984) Hormonal regulation of fruit bud formation in fruit trees. Acta Hortic 149: 13–23
Iwahori S, Tominaga S and Yamasaki T (1988) Stimulation of fruit growth of kiwifruit, Actinidia chinensis Planch., by N-(2-chloro-4-pyridyl)-N-phenylurea, a diphenylurea derivative cytokinin. Sci Hortic 35: 109–115
Kotob MA and Schwabe WW (1971) Induction of parthenocarpic fruit in Cox's Orange Pippin apples. J Hort Sci 46: 89–93
Looney NE, Pharis RP and Noma M (1985) Promotion of flowering in apple trees with gibberellin A4 and C-3 epi-gibberellin A4. Planta 165: 292–294
Luckwill LC (1960) The effect of gibberellic acid on fruit set in apples and pears. Rep Long Ashton Res Station (1959): 59–64
Meador DB and Taylor BH (1987) Effect of early season foliar sprays of GA4+7 on russeting and return bloom of Golden Delicious apple. Hort Science 22: 412–415
Modlibowska J (1972) The effect of gibberellins and cytokinins on fruit development of Bramley's Seedling apple. J Hortic Sci 47: 337–340
Ogata R, Saito T and Oshima K (1989) Effect of N-phenyl-N-(4-pyridyl) urea on fruit size: apple, japanese pear, grape-vine and kiwi fruit. Acta Hortic 239: 395–398
Schwabe WW (1973) The induction of parthenocarpy in Cox's Orange Pippin. Acta Hortic 34: 311–316
Schwabe WW and Mills JJ (1981) Hormones and parthenocarpic fruit set, a literature survey. Hortic Abstracts 51: 661–698
Sugiyama N, Sansavini S, Neri D and Tartarini S (1993) Effect of CPPU on fruit and shoot growth of apple. J Hortic Sci 68: 673–677
Varga A (1966) The specificities of apple cultivars and gibberellins in the induction of parthenocarpic fruits. Proc Kon Ned Akad Wetensch C 69: 641–644
Wertheim SJ (1973) Fruit set and june drop in Cox's orange pippin apple as affected by pollination and treatment with a mixture of gibberellins A4 and GA7. Sci Hortic 1: 85–105
Wertheim SJ (1982) Fruit russeting in apple as affected by various gibberellins. J Hortic Sci 57: 283–288
Williams MW and Letham DS (1969) Effect of gibberellins and cytokinins on development of parthenocarpic apples. Hort Science 4: 215–216
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Bangerth, F., Schröder, M. Strong synergistic effects of gibberellins with the synthetic cytokinin N-(2-chloro-4-pyridyl)-N-phenylurea on parthenocarpic fruit set and some other fruit characteristics of apple. Plant Growth Regul 15, 293–302 (1994). https://doi.org/10.1007/BF00029902
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DOI: https://doi.org/10.1007/BF00029902