Cryopreservation of Plant Cells, Tissues and Organs

Morphogenetic response of shoot tips to cryopreservation by encapsulation-dehydration in a solid mutant and periclinal chimeras of Chrysanthemum × grandiflorum /Ramat./Kitam.

“…Our research, however, confirmed the possibility of securing not only the entire meristem (both tunica and the deeper parts of the corpus) but also leaf primordia and even large parts of young leaf with no change in their structure. Similar to our results, Kartha (1985) reported that in Dianthus most of subapical tissue was damaged, while the meristem and leaf primordia remained viable. As a consequence, a fully protected shoot tip was capable of forming a single shoot in post-rewarming culture.…”

“…Electron microscopy is a very useful tool used in cryobiology, which enables tracking how soon after rewarming do the thawed tissue regain its original state of vacuolisation, or the explant regeneration path. Histological and ultrastructural (transmission electron microscopy, TEM) analyses of Dianthus shoot tips (Kartha 1985), Hypericum perforatum L. tissues (Skyba et al 2012), as well as Dendrobium sonia-28 (Poobathy et al 2013) and Oncidium hamana 'Elfin' (Miao et al 2005) protocorm-like bodies (PLBs) were used in order to indicate to which explant regions do the freezing and thawing cycles inflict most damages. Cellular and subcellular changes after various cryopreservation regimes were examined to explain the mechanism of the beneficial effect of different pretreatment conditions (Miao et al 2005;Mikuła et al 2005;Kushnarenko et al 2010).…”

Caracterização morfoanatômica e bioquímica da germinação, sistemas de conservação ex situ e indução de calos para a embriogênese somática de pinhão-manso (Jatropha curcas L.)

“…De acordo com Benson et al (2000), tanto a velocidade de congelamento quanto a de descongelamento influenciam a germinação e, quanto mais rápido ocorrer o descongelamento das sementes, melhor deve ser a preservação de suas características fisiológicas. Para os autores, o método de descongelamento lento (temperatura ambiente) se torna questionável, uma vez que existe a possibilidade de ocorrer um recongelamento durante este período, ocosionando a formação de cristais de gelo que podem provocar injurias na membrana plasmática, resultando em danos ou morte celular.…”