The influence of the cooling of donor cultures on the in vitro adventitious regeneration and carbohydrate metabolism of four dwarfing apple rootstocks

Abstract

We examined the effects of cooling applied for 4 to 20 weeks on donor cultures of four dwarfing apple rootstocks (P16, P22, P59 and M26). Our aim includes increasing their competence for in vitro adventitious shoot regeneration from the leaves. Donor cultures were maintained on a shoot multiplication medium at 4°C in the dark for 4 months, followed by subculture on a fresh medium for 4 weeks. The cooling of the cultures caused an increase in the adventitious shoot number and a decrease in the starch content and an increase in the soluble sugar content (monosaccharides, raffinose and stachyose). The accumulation of stachyose in response to cold is a new observation, and it suggests that raffinose and stachyose play important role in the acclimation of dwarf apple rootstocks to low temperatures.

Effect of light conditions and ABA on cold storage and post-storage propagation of Taraxacum pieninicum

“…A similar effect was obtained after storage of Podophyllum peltatum where the proliferation rate after 4 and 8 months at a temperature of 10°C was higher than at 25°C (Lata et al 2010). Cold storage in the dark of apple cultures also caused an increase in adventitious shoot number (Orlikowska et al 2010).…”

“…Poplar shoots were in better condition after storage in the dark than under light (Hausman et al 1994). Vigorous growth of Malus and Pistacia lentiscus after cooling was obtained also following dark storage (Orlikowska et al 2010;Koç et al 2014). The presence of 5 lM ABA in the medium even more decreased condition of T. pienicum shoots.…”

Simple strategy for the in vitro conservation of Alnus glutinosa (L.) Gaertn. germplasm

“…Malus (Orlikowska et al 2010) and Digitaria (Garbero et al 2012) report smaller starch granules or the disappearance of starch granules under chilling stress. Low-temperature stress (5ºC for 12h) has been shown to be associated with starch degradation due to β-amylase, a major enzyme of starch breakdown in Arabidopsis chloroplasts (Fulton et al 2008) leading to release of cold-protective maltose (Kaplan and Guy 2004).…”