Light and temperature sensing and signaling in induction of bud dormancy in woody plants

Abstract

In woody species cycling between growth and dormancy must be precisely synchronized with the seasonal climatic variations. Cessation of apical growth, resulting from exposure to short photoperiod (SD) and altered light quality, is gating the chain of events resulting in bud dormancy and cold hardiness. The relative importance of these light parameters, sensed by phytochromes and possibly a blue light receptor, varies with latitude. Early in SD, changes in expression of light signaling components dominate. In Populus active shoot elongation is linked to high expression of FLOWERING LOCUS T (FT) resulting from coincidence of high levels of CONSTANS and light at the end of days longer than a critical one. In Picea, PaFT4 expression increases substantially in response to SD. Thus, in contrast to Populus-FT, PaFT4 appears to function in inhibition of shoot elongation or promotion of growth cessation. Accordingly, different FT-genes appear to have opposite effects in photoperiodic control of shoot elongation. Reduction in gibberellin under SD is involved in control of growth cessation and bud formation, but not further dormancy development. Coinciding with formation of a closed bud, abscisic acid activity increases and cell-proliferation genes are down-regulated. When dormancy is established very few changes in gene expression occur. Thus, maintenance of dormancy is not dependent on comprehensive transcriptional regulation. In some species low temperature induces growth cessation and dormancy, in others temperature affects photoperiod requirement. The temperature under SD affects both the rate of growth cessation, bud formation and depth of dormancy. As yet, information on the molecular basis of these responses to temperature is scarce.

Shoot growth of Merlot and Cabernet Sauvignon grapevine varieties

“…Several authors reported that temperature, water and nutrient availability play important roles in the induction of shoot growth cessation (Koundouras et al, 1999;Leeuwen et al, 2004;Coipel et al, 2006). In addition, photoperiod (Wake & Fennell, 2000;Heide, 2008;Garris et al, 2009;Victor et al, 2010) and probably thermoperiod (Olsen, 2010;Tanino et al, 2010) also play important roles.…”

“…The vegetative growth phase is dependent on several factors, and meteorological variables have an essential role in the control of grapevine development (Pouget, 1972;Andreini et al, 2009;Garris et al, 2009;Olsen, 2010).…”

“…Recently, it has been suggested that those factors may be synergistic, inducing biochemical pathways of hormonal regulation, which control the completion of the meristematic activity of the shoots (Garris et al, 2009;Olsen, 2010;Tanino et al, 2010). Temperature affects the cell metabolism, carbon accumulation and other biochemical processes (Tanino et al, 2010).…”

“…Temperature affects the cell metabolism, carbon accumulation and other biochemical processes (Tanino et al, 2010). The variation in the photoperiod, including long nights, affects the phytochromes (photoreceptors), which control signal transduction in order to regulate shoot growth (Chao et al, 2007;Olsen, 2010;Tanino et al, 2010;Victor et al, 2010).…”

The Cold Awakening of Doritaenopsis ‘Tinny Tender’ Orchid Flowers: The Role of Leaves in Cold-induced Bud Dormancy Release

“…Most flowering plants use photoperiod and temperature variations to detect seasonal shifts and reproductive periods (Boss and others 2004;Jaeger and others 2006;Penfield 2008;Adrian and others 2009;Amasino 2010;Olsen 2010). Vernalization and bud dormancy are two distinct mechanisms that allow temperature changes to affect flowering time (Chouard 1960;Penfield 2008).…”