Changes in carbohydrate contents of Zantedeschia leaves under gibberellin-stimulated flowering

Abstract

The effect of gibberellic acid (GA 3 ) on the carbohydrate accumulation in relation to vegetative growth of Zantedeschia 'Black Magic' plants undergoing transition to flowering was investigated. In response to GA treatment the carbohydrate level increased independently of earlier stimulation of shoot emergence. Under vegetative growth stage the content of reducing sugars of leaf blades was 2.5-fold higher than in control plants, and suggests the stimulation of photosynthetic activity. The changes observed during the flowering, in principle noted in petiole tissues, support the GA-effect on assimilate transport to the sink organs. Moreover, the high level of non-structural carbohydrates in petiole tissues, in particular reducing sugars, can be an effect of photosynthetic activity of these organs and/or essential for osmoregulation and high turgor pressure. The results indicate that apart from the influence on the shoot emergence, the GAs may stimulate the photosynthetic activity from the beginning of shoot growth and are thus responsible for the enhancement of callas flower yield.

Ácido giberélico na indução e qualidade do florescimento de orquídea Phalaenopsis ‘White Dream’

“…estas condições, por sua vez, ativam a enzima α-amilase, resultando no aumento da relação C/N nas folhas (TAIZ e ZEIGER, 2008). O GA 3 também estimulou o florescimento e a atividade fotossintética em Zantedeschia 'Black Magic', sendo esse outro fator associado ao aumento da relação C/N pelas GAs (KOZLOWSKA et al, 2007). KATAOKA et al (2004) observaram aumento do teor de sacarose nas folhas de plantas de Phalaenopsis em pré-florescimento, tendo o uso de temperaturas altas reduzido tanto o teor de sacarose quanto a taxa de florescimento desta orquídea.…”

“…O GA 3, aplicado pela imersão na concentração de 100mg L -1 em colmos de Gladiolus grandiflorus 'eurovision', acelerou o florescimento e aumentou a porcentagem de plantas floridas, comprimento de inflorescência e número de flores nesta espécie, melhorando a produtividade e a qualidade da floração (KARAGÜZEL et al, 2007). Também foi observado aumento no número de flores em Zantedeschia 'Black Magic' pela aplicação de GA 3 (KOZLOWSKA et al, 2007). A aplicação de GA 3 em morango (Fragaria x ananassa) aumentou o número, o peso e a qualidade de frutos produzidos (DUARTE FILHO et al 2004), mostrando que o efeito desse regulador vegetal na qualidade não se aplica apenas a flores.…”

The Role of Plant Growth Regulators in the Development of in vitro Flowering, Histology and Ultrastructural Studies in Impatiens balsamina cv. Dwarf Bush

“…Early in vitro flowering of micropropagated plantlets can shorten their breeding cycle to generate better quality of plant varieties to meet market demand (Haque and Ghosh, 2013). In this study, we have induced in vitro flowering and promoted adventitious shoot formation of I. balsamina GA 3 was found to promote earlier in vitro flowering in I. balsamina GA 3 has previously been reported to promote flowering in long day ornamental plants, such as Zantedeschia (Kozlowska et al, 2007) and a facultative long day plant, Brunonia (Wahyuni et al, 2011).…”

Global Change and Sustainable Development in Mountain Regions – Proceedings of the COST Strategic Workshop

“…Different amounts of yeast were cultivated in suspension media containing carbohydrates and phosphate buffer pH 7. The assimilation levels of monosaccharide glucose and disaccharide sucrose in the yeast medium were quantified by 3,5-dinitrosalicilic acid (DNS) colorimetric method (Kozłowska et al, 2007). In parallel, the quantity of the inorganic phosphate converted into organic one in the progress of cell cycle was analyzed by means of Molybdenum blue phosphorous method (He and Honeycutt, 2005).…”