In vitro morphogenetic responses from obligatory apomictic Taraxacum belorussicum Val. N. Tikhom seedlings explants

Abstract

Taraxacum belorussicum Val. N. Tikhom, a poorly known and obligatory apomictic species, is an attractive plant material for studying the embryological, genetic and molecular mechanisms of apomixis. This work aims to obtain an efficient protocol for Taraxacum belorussicum regeneration. Four types of explants (cotyledons, hypocotyls, meristems and roots) that were taken from 2-weeks-old seedlings were used for in vitro cultures, and a fast and efficient protocol of T. belorussicum regeneration was obtained. Various ½ MS-based media containing IAA (5.71 µM), TDZ (4.54 µM) and PSK (100 nM) were chosen to assess the morphogenetic abilities of selected T. belorussicum explants. Studies on the role of PSK were done in three independent experiments, where the most significant factors were always light and darkness. All explants produced callus by the third day of culture and adventitious shoots after 7 days, although in an asynchronous indirect manner, and with different intensities for all explant types. The most preferred medium culture for hypocotyl, cotyledon and meristem explants was ½ MS + TDZ, and ½ MS + IAA + TDZ + PSK for roots which were the only explant sensitive to PSK. A short darkness pretreatment (8 days) in PSK medium was found suitable to enhance organogenesis. Secondary organogenesis was observed for regenerated plants on meristem explants from the ½ MS + IAA + TDZ + PSK medium. A weak somatic embryogenesis was observed for hypocotyl and cotyledon explants from ½ MS + IAA + TDZ and ½ MS + IAA + TDZ + PSK media. Histological and scanning electron microscope images (SEM) of T. belorussicum confirmed indirect organogenesis and somatic embryogenesis. Plant material treated with aniline blue solution revealed the presence of callose in the cell walls of cotyledon and hypocotyl explants. The presence of extracellular matrix (ECM) and heterogenic structure of callus was also verified by scanning electron microscopy and light microscopy, confirming the high morphogenetic ability of T. belorussicum. Key messageAn efficient regeneration protocol for Taraxacum belorussicum, the obligatory apomict, was obtained. Application of PSK revealed the significance of light and darkness as a key factor in the morphogenetic response. A short darkness pretreatment (8 days) in PSK medium was found suitable to enhance organogenesis. Histological and scanning electron microscope images confirmed indirect organogenesis and somatic embryogenesis presence. The protocol can enhance the knowledge about this species in studying the embryological, genetic and molecular mechanisms of apomixis.Communicated by Sergio J. Ochatt.

The Efficient and Easy Micropropagation Protocol of Phyllanthus niruri

“…Clorox ® , a conventional bleach that consists of 5.25% of sodium hypochlorite (NaOCl), has the ability to penetrate the inner layers of the plant. It has been extensively used along with ethanol as an effective surface sterilizing agent in various plant species such as Ludisia discolour [41], Gerbera hybrida [42], Ananas comosus [43], Jatropha curcas [44], Aquilaria malaccensis [45], sour cherry [46] and Taraxacum belorussicum [47].…”

Effective callus induction and plant regeneration in callus and protoplast cultures of Nigella damascena L.

“…The positive effect of PSK, a peptidyl plant growth factor, on cell proliferation was reported for the first time by Matsubayashi and Sakagami (1996) in mesophyll cell cultures of Asparagus officinalis. It was also shown to playing a role in diverse aspects of plant development and reproduction, including the formation of tracheary elements and adventitious roots (Yamakawa et al 1998;Matsubayashi et al 1999), somatic embryogenesis (Ochatt et al 2018;Gałuszka et al 2019), and pollen germination (Chen et al 2000). Thus far, its ability to promote mitotic activity was confirmed in numerous suspension and protoplast cultures of both monocotyledonous and dicotyledonous species (Matsubayashi et al 1997(Matsubayashi et al , 2004Maćkowska et al 2014;Adamus 2017, 2019) and as a cell division promoter, PSK-treatment may be particularly preferred in cell cultures of so called recalcitrant species (Grzebelus et al 2012b).…”

Promotive effect of phytosulfokine - peptide growth factor - on protoplast cultures development in Fagopyrum tataricum (L.) Gaertn

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