Formation and Spread of Ice in Plant Tissues

Response of Germination Rate to Variable Drying Conditions and Moisture Contents for Storage of Dehisced Korean Ginseng Seeds

“…Such differences depend on various factors, such as water content, physio-chemical state, rehydration, and ice crystallization peak (Ashworth, 1992;Sparks et al, 2001;Yoon et al, 2005). Kim et al (2008) reported that seed MC needs to be strictly controlled for routine application of cryopreservation to Korean ginseng seeds due to the morphological and physiological heterogeneity of the seeds (seed length and thickness, dehiscence) and that the hydration window for cryopreservation of Korean ginseng seeds is narrow, namely 8-11%.…”

Genomics and Functional Genomics of Winter Low Temperature Tolerance in Temperate Fruit Crops

“…Tolerating the presence of ice in tissue apoplast and cellular dehydration as water moves from the cell to ice in the extracellular spaces allows many plant tissues to tolerate lower temperatures without injury (Levitt 1980). In apple (Malus), the bark and phloem tissue tolerate extracellular ice formation while the xylem parenchyma cells tolerate subzero temperatures by supercooling as freezing of the xylem parenchyma results in tissue death (Ashworth, 1992;Gusta et al, 2009;. Supercooling limits the strain of freeze dehydration, although progressive dehydration can occur with extended subzero temperatures.…”

“…Development of the ability to supercool depends on low temperature and/or photoperiod induced acclimation responses that promote reduction in water content, changes in cellular biochemistry and the development of barriers to ice propagation from the stem into the bud tissue (Ashworth, 1982;Ashworth and Wisniewski, 1991;Burke and Stushnoff, 1978;Jones et al, 2000;Wisniewski, 2012, Levitt, 1980). In grapevine (Vitis species) and some Prunus species, the overwintering flower or compound buds supercool and adjacent stem tissue may tolerate extracellular freezing (Ashworth, 1992;Fennell, 2004;Mathers, 2004;Kader and Proebsting, 1992;Quamme et al, 1995). The ability to supercool depends on tissue water content, shoot morphology, the stage of bud development and absence of intrinsic and extrinsic nucleators.…”

“…Survival of subzero temperatures depends on the woody plants ability to acclimate in response to low temperature and or photoperiod; promoting physical and biochemical changes in multiple tissues, which will allow the plant to avoid ice nucleation in tissues or compartmentalize ice in locations where it does not cause injury (Ashworth, 1982;1992;Gusta and Wisniewski, 2012;Pearce, 2001;Wisniewski et al, 2004). It should be noted that freezing tolerance and avoidance traits within a given species are not static, rather they are dynamically influenced by stage of development, intrinsic and extrinsic nucleators and environmental conditions (Gusta and Wisniewski, 2012;Pearce 2001).…”

“…Acclimation processes are marked by a reduction in water content, fluxes in calcium, modifications in membranes, metabolic reprogramming, accumulation of carbohydrates, amino acids, proteins and secondary metabolites and changes in cell wall structure (Ashworth, 1992;Fennell, 2004;Gusta and Wisniewski, 2012;Guy, 2003;Levitt, 1980;Smallwood and Bowles, 2002;Theocharis, 2012; 2006; Wisniewski et al, 2009). Correlation of these biochemical changes with freezing tolerance has provided many gene candidates for functional gene analysis; however the complexity of winter survival indicates that, rather than single gene analysis, targeted and holistic analysis are needed to precisely determine the genetic mechanism involved in winter survival.…”