Ethylene and polyamine interactions in morphogenesis of Passiflora cincinnata: effects of ethylene biosynthesis and action modulators, as well as ethylene scavengers

Abstract

Ethylene is a plant hormone that is of fundamental importance to in vitro morphogenesis, but in many species, it has not been thoroughly studied. Its relationship with polyamines has been studied mainly because the two classes of hormones share a common biosynthetic precursor, S-adenosylmethionine (SAM). In order to clarify whether competition between polyamines and ethylene influences in vitro morphogenetic responses of Passiflora cincinnata Mast., a climacteric species, different compounds were used that act on ethylene biosynthesis and action, or as ethylene scavengers. Treatment with the ethylene inhibitor, aminoethoxyvinylglycine (AVG) caused a greater regeneration frequency in P. cincinnata, whereas treatment with the ethylene precursor, 1-aminocyclopropane-1-carboxylic-acid (ACC) lessened regeneration frequencies. The data suggested that levels of polyamines and ethylene are not correlated with morphogenic responses in P. cincinnata. It was ascertained that neither the absolute ethylene and polyamine levels, nor competition between the compounds, correlated to the obtained morphogenic responses. However, sensitivity to, and signaling by, ethylene appears to play an important role in differentiation. This study reinforces previous reports regarding the requirement of critical concentrations and temporal regulation of ethylene levels for morphogenic responses. Temporal regulation also appeared to be a key factor in competition between the two biosynthetic pathways, without having any effects on morphogenesis. Further studies investigating the silencing or overexpression of genes related to ethylene perception, under the influence of polyamines in cell differentiation are extremely important for the complete understanding of this process.

Somatic embryogenesis of a wild passion fruit species Passiflora cincinnata Masters: histocytological and histochemical evidences

“…Among these, a number of noncommercially grown species have attracted attention because of their interesting characteristics that may improve fruit yield and quality, as well as cultivars that are resistant to diseases or pests (Vieira and Carneiro 2004;Junqueira et al 2005;Zerbini et al 2008). Thus, in vitro organogenesisbased regeneration systems have been developed and applied to various aspects of passion fruit biotechnology, such as micropropagation (Dornelas and Vieira 1994;Drew 1997;Alexandre et al 2009;Pinto et al 2010a;Garcia et al 2011), germplasm conservation (Passos and Bernacci 2005), physiological studies (Mensuali-Sodi et al 2007;Faria and Segura 1997;Dias et al 2009Dias et al , 2010, breeding (Rêgo et al 2010, and genetic transformation (Alfenas et al 2005;Trevisan et al 2006).…”

“…passiflorae) (Oliveira and Ruggiero 2005). Commonly known as shark passion fruit, this species performs well in vitro, showing an elevated frequency of shoot-bud formation (Lombardi et al 2007;Dias et al 2009Dias et al , 2010Silva et al 2011). In addition, it is one of the few species of the genus in which somatic embryogenesis has been described (Reis et al 2007;Silva et al 2009;Paim Pinto et al 2010) and is considered a model species for further morphogenic studies of the genus ).…”

Morphometry, in vitro-ex vitro germination and tetrazolium testing of stinking passionflower [Passiflora foetida var. glaziovii Killip] (Passifloraceae) seeds

“…In vitro propagation is a promising approach for generating aseptic seedlings and for reducing or overcoming dormancy, in addition to other possibilities, such as obtaining virus-free seedlings (Prammanee et al, 2011) and producing secondary metabolites (Passos et al, 2004;Rosa and Dornelas, 2012). Complete removal of the seed integument is an essential step for the in vitro germination of Passiflora edulis f. flavicarpa (Dias et al, 2009;Rêgo et al, 2011), P. cincinnata (Dias et al, 2009;Dias et al, 2010), P. foetida (Rosa and Dornelas, 2012), and P. foetida var. glaziovii.Temperature also directly influences germination because it can affect water absorption and the biochemical reactions involved in metabolism.…”

In Vitro Plant Tissue Culture: Means for Production of Passiflora Species

“…Ethylene is a gaseous hormone produced in most plant tissues and is involved in several stages of the plant life cycle (Dias et al, 2010). Ethylene accumulates in culture vessels, although vials allow the exchange of ethylene, often the production is higher than the loss, which leads to its accumulation in culture vessels (Pua, 1999).…”