Roles of Cytokinin and Abscisic Acid in the Maturing of Strawberry Fruits

Abstract

SummaryThe changes of the activity of growth inhibitors in the latter half of the development of strawberry fruits and the interaction of cytokinin and growth inhibitors on fruit development were investigated.1. Fruits grown at day/night temperature of 30°C/25°C matured earlier than those at 20°C/17°C. The activity of growth inhibitors in the fruits increased with their maturing, and inhibitor activity in the fruits grown at high temperature appeared earlier than that at low temperature.In chromatography of inhibitors on a Sephadex column, peak of inhibitory activity in a bioassay using rice seedling was found in fractions 5 and 6 corresponding with those of authentic ABA.2. Number of days to maturity of fruits in vitro decreased as the concentration of ABA increased in the medium. Number of days to maturity was definitely affected by the concentration of ABA independently of BA concentration when fruits were cultured on the medium with BA and ABA. Fruit maturing was suppressed and inhibitor activity in them decreased when fruits were cultured on the medium with BA.Based on these results, following conclusion can be induced. In the latter half of the development of strawberry fruits, ABA synthesized actively owing to lowering of cytokinin activity in fruits promotes fruit maturing.

Abscisic Acid Plays an Important Role in the Regulation of Strawberry Fruit Ripening

“…These results demonstrated that TRV-mediated VIGS is a viable strategy to silence gene expression in strawberry fruit. There are several reports suggesting that strawberry fruit ripening may be promoted by ABA (Kano and Asahira, 1981;Manning, 1994;Perkins-Veazie, 1995;Jiang and Joyce, 2003). To confirm this, we first quantified ABA levels in the receptacles of Fugilia strawberry fruit and detected an increase during development (Fig.…”

“…It has been hypothesized that the ABA-auxin ratio could be part of the signal that triggers fruit ripening (Archbold and Dennis, 1984;Perkins-Veazie, 1995). Auxin stimulates receptacle expansion during early fruit development and later inhibits fruit ripening (Given et al, 1988), whereas exogenous ABA markedly promotes fruit maturation (Kano and Asahira, 1981;Manning, 1994;Perkins-Veazie, 1995;Jiang and Joyce, 2003). This model was supported by studies of another nonclimacteric fruit, the grape berry (Coombe, 1992;Davies et al, 1997;Giovannoni, 2001;Rodrigo et al, 2003;Yu et al, 2006).…”

“…It was previously observed that 9-cisepoxycarotenoid dioxygenase (NCED), a key enzyme involved in ABA biosynthesis (Qin and Zeevaart, 1999), is implicated in the ripening of several fruits, including avocado (Persea americana; Chernys and Zeevaart, 2007), orange (Citrus sinensis; Rodrigo et al, 2006), grape (Vitis vinifera), peach (Prunus persica; Zhang et al, 2009a), and tomato (Solanum lycopersicum; Zhang et al, 2009b). Strawberry (Fragaria ananassa), which is widely used as a research model to study nonclimacteric fruits, has also been associated with ABA as an inducer of ripening (Kano and Asahira, 1981;Manning, 1994;Perkins-Veazie, 1995;Jiang and Joyce, 2003). However, direct genetic/molecular evidence has not yet been reported.…”

Cytokinin antagonizes ABA suppression to seed germination of Arabidopsis by downregulating ABI5 expression

“…For decades, numerous studies demonstrate the antagonistic effects of cytokinin and ABA in plant development (Das et al. , 1976; Kano and Asahira, 1981; Blackman and Davies, 1983; Christianson, 2000; Tanaka et al. , 2006; Polanská et al.…”

MicroRNAs play an important role in the regulation of strawberry fruit senescence in low temperature

“…ABA, as the important phytohormone, besides the key roles on plant growth and responses to environmental stresses (Leung and Giraudat, 1998;Finkelstein et al, 2002;Himmelbach et al, 2003;Hirayama and Shinozaki, 2007) was also involved in the ripening of climacteric (Chernys and Zeevaart, 2007;Zhang et al, 2009a) and non-climacteric fruit (Rodrigo et al, 2003;Davies et al, 1997;Zhang et al, 2009b), including strawberry fruit (Kano and Asahira, 1981;Manning 1994;Jiang and Joyce, 2003;Jia et al, 2011). In Arabidopsis, PYR1/PYL1-PP2C-SnRK2 is one of the core signaling transduction networks of ABA, in which ABA could promote the interaction of PYR1/PYL1 and PP2C, repress PP2C and activate SnRK2, then transmit the ABA signals Ma et al, 2009;Park et al, 2009).…”