Acclimation to Ex Vitro Conditions in Ninebark

Abstract

Acclimation is the final phase of micropropagation and often decisive for its economic output. The aim of the experiments was to evaluate the effect of abscisic acid (ABA) and supplementary light on acclimation and leaf anatomy of the in vitro-rooted plants of ninebark (Physocarpus opulifolius L.). The initial material came from 8–10-week-old in vitro cultures on ½MS supplemented with 1 mg·L−1 IBA. After potting, plantlets were sprayed with ABA solutions or distilled water and were grown either under natural daylight or under supplemental sodium light at 230 μmol·m−2·s−1 between 2 and 9 p.m. All measurements and anatomical observations were done after eight weeks in the greenhouse. Supplementary lighting significantly increased the percentage of acclimatized plants, plant height and the internode number. Plant growth was also positively affected by 1 mg·L−1 ABA. During acclimation, the photosynthesis rate increased while the transpiration and stomatal conductance dropped. The assimilation pigment contents increased under supplemental lighting while ABA had no detectable effect. However, relative to water controls, ABA increased photosynthesis, reduced transpiration, and stomatal conductance in plants growing under both light conditions. Leaves from the in vitro plants were about two times thinner than those from plants growing in soil, with only a single layer of the palisade parenchyma, hence with lower proportion in relation to the spongy parenchyma. Supplementary light during acclimation increased leaf thickness but only in the water control while it decreased it in the ABA-treated plants. ABA increased the mesophyll thickness but only in plants growing under natural light. In conclusion, supplementary light and treatment with ABA enhance acclimation of micropropagated ninebark plants.

WITHDRAWN: Bio-hardening of in vitro raised plants of Geneva (G.) series clonal rootstocks of apple (Malus X domestica Borkh.)

“…The conclusion of in vitro propagation is marked by hardening phase which is quite important for determining the success of the end product [10]. Usually,primary hardening of in vitro raised plantlets is done in polyhouse chambers followed by their secondary hardening in shade houses providing shade to the growing plantlets [12]…”

“…During development of plants, certain abnormalities occur regarding morphology, anatomy and physiology because of various conditions. Due to sudden change of environment during growth period the ex-vitro transfer of plants cause damage, so for that hardening period is must which can be given under in vitro conditions or when transferred to polyhouse [10]. At this phase, in vitro raised plantlets are quite susceptible to losses [11].…”

Anatomical Structures of Saskatoon Berry (Amelanchier Medik.)Leaves Under Different Cultivation Conditions

“…E-mail: katyaraevab@gmail.com In vitro culture is carried out under conditions of high relative humidity, which affects the anatomical structure of newly formed tissues and organs in the explant (Hazarika, 2006). This leads to a decrease in the ability of plants to maintain homeostasis under ex vitro conditions and, subsequently, reduces the number of adapted plants (Blanke and Belcher, 1989;Romano and Martins-Loução, 2001;Apóstolo et al, 2005;Pospísilová et al, 2007;Werner et al, 2018;Mitrofanova et al, 2018;Jagiełło-Kubiec, 2021). During the process of adaptation to ex vitro conditions, in vitro-derived plantlets are exposed to water stress.…”

Use of Biotechnological Methods to Support the Production of New Peach Hybrids

“…In turn, the mechanisms of species, forms and cultivars adaptation to environmental conditions are determined by their anatomical, morphological, physiological and biochemical structural features. The acclimatization process, that is, the transfer of a plant from in vitro to ex vitro conditions, is often a critical stage for a seedling survival [12][13][14][15][16]. There are a number of differences between in vitro and ex vitro conditions in terms of light intensity and quality, relative air humidity, availability of nutrients, substrates and gas concentration.…”