Putrescine extends effective pollination period in ‘Comice’ pear ( Pyrus communis L.) irrespective of post-anthesis ethylene levels

• Published in: Scientia horticulturae Vol. 49; no. 3; pp. 211 - 221
• Main Authors: Crisosto, C.H., Lombard, P.B., Richardson, D.G., Tetley, R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 1992; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Economic plant physiology; endogenous polyamines; ETHYLENE; ETILENO; evolved ethylene; flower culture in vitro; Flowering, floral biology, reproduction patterns; Fundamental and applied biological sciences. Psychology; Growth and development; ovule senescence; POLIAMINAS; POLINIZACION; pollen tube growth; POLLINATION; POLLINISATION; POLYAMINE; POLYAMINES; PYRUS COMMUNIS; vacuum extracted ethylene; TMF = time of maximum fertilization; ACC = 1-aminocyclopropane-1-carboxylic acid; EPP = effective pollination period, FPA = formaldehyde/propionic acid/95% ethanol; OLP = ovule longevity period; SPD = spermidine; flower culture in vitro; evolved ethylene; SPM = spermine; vacuum extracted ethylene; PUT = putrescine; SAM = S-adenosyl-methionine; ovule senescence; pollen tube growth; endogenous polyamines; Pyrus communis; Polyamine; Flower; Senescence; Application time; Rosaceae; Ethylene; Putrescine; Fecundation; Pollen tube; Phenological stage; Pollination; Controlled environment study; Dicotyledones; Biogenic amine; Angiospermae; Ovule; Spermatophyta; Yield; Fruit tree; Mechanism of action; Fruit setting
• ISSN: 0304-4238; 1879-1018
• DOI: 10.1016/0304-4238(92)90158-9

Putrescine (PUT) 10 −3 M, a polyamine applied at bloom, enhanced pollen tube ovule penetration and delayed ovule senescence, extending the effective pollination period of cultivar ‘Comice’ pear ( Pyrus communis L.) by at least 2 days and 4 days in 1985 and 1986, respectively, without reducing post-pollination flower ethylene levels. Evolved flower ethylene peaked at pollination and again at petal senescence in vivo while vacuum-extracted ethylene peaked only during fertilization. Endogenous polyamine levels were not related to ethylene levels during the post-bloom period in any flowers. After pollination, putrescine-treated flowers exhibited lower levels of evolving ethylene than untreated flowers. Hand-pollinated flowers had greater polyamine levels than unpollinated. Putrescine-treated flowers had lower endogenous polyamine levels and higher nitrogen contents than untreated flowers. Earlier pollen tube penetration, delayed ovule longevity and extended ‘Comice’ effective pollination period from a PUT application were not associated with reduced post-anthesis, ethylene levels.