Adventitious shoot organogenesis from leaf explants of Portulaca pilosa L.

Abstract

This study established, for the first time, shoot proliferation and plant regeneration protocols via shoot organogenesis from leaf explants of a medical and ornamental plant, Portulaca pilosa L. the optimal proliferation of axillary shoots was 6.2-fold within 30 days on Murashige and Skoog (MS) medium supplemented with 3.0 µM 6-benzyladenine (BA). Shoots could be induced directly from leaf explants, forming an average of 3.8 adventitious shoots per explant, on optimal MS medium supplemented with 1.0 µM thidiazuron (TDZ) and 0.1 µM α-naphthaleneacetic acid (NAA). A higher concentration of TDZ (3.0 µM), alone or in combination with 0.1 µM NAA, induced somatic embryo-like shoot buds and then developed into real shoots. Rooting was easier since roots were induced on all rooting media within one month. Half-strength MS medium free of plant growth regulators was best for rooting. Rooted plantlets were transferred to a sand: perlite (1:1, v/v) substrate, resulting in highest survival (90%). Plantlets showed more robust growth, however, on substrates of yellow mud: perlite (1:1, v/v) or peat soil: vermiculite: perlite (1:1:1, v/v).Portulacaceae, consisting of annual or perennial plants and distributed in temperate and tropical regions of the world, is one of 19 families of terrestrial plants that display C 4 photosynthesis 1,2 . Portulaca pilosa L. (Portulacaceae) is an annual herb native to Asia but that spread to North and South America 3,4 . In China, P. pilosa is distributed only in southern provinces where it grows in the wild on seashores, in orchards, wastelands, and roadsides. A diterpenoid, pilosanone C, was isolated from the shoots and roots of P. pilosa 5,6 . P. pilosa contains a variety of chemical components, including polyphenols, flavonoids, sugars, organic acids, steroids, tannins, steroids, and others, but the highest content is of flavonoids and polyphenols explaining its high antioxidant activity and thus high toxicity to tumor cells 7,8 . It is commonly used as a traditional remedy to treat antipyresis and analgesia and serves as a hepato-protective, anti-diarrheal, and diuretic for healing burns, erysipelas, and injuries 9 . Phytochemical screening revealed the presence of reducing sugars, phenols, tannins, steroids, terpenoids, cardiac glycosides, and carotenoids in the ethanolic extract of dried aerial parts of P. pilosa, which also demonstrated an antimicrobial effect against Pseudomonas aeruginosa 7,10 . In addition, P. pilosa, which has red-purple flowers that bloom over a long flowering period, is regarded as an excellent ornamental succulent plant 11 .The capsules of P. pilosa, which is autogamous and self-compatible, yield a large number of seeds that require light and 25 °C for maximum germination 12 . P. pilosa seeds show no dormancy and poor viability in long-term storage 13 . Therefore, seeds need to be sown as quickly as possible when they mature. In fact, in natural conditions in the wild, it is not always possible to attain suitable seed germination conditions related to soil, light, t...

Indirect in vitro Regeneration of the Medicinal Plant, Aspilia africana, and Histological Assessment at Different Developmental Stages

“…In this study, although all rooting responses were very good, the best, with consistently highest values of all the measured rooting parameters, was in 1/2 MS augmented with 0.1 mg/L NAA, although were not significantly different from other treatments for some parameters. In agreement with our findings, a half-strength MS medium was reported in several studies to be effective for the rooting of many in vitro regenerated plant species such as Ruscus hypophyllum (Winarto and Setyawati, 2014), Phlox Pilosa (Chen et al, 2020), and Phellodendron amurense (Yang et al, 2011). Hariprasath et al (2015) also recorded optimum rooting in S. candicans in 1/2 MS medium, although it was supplemented with a much greater concentration of 3.0 mg/L NAA.…”

A Novel and Efficient In Vitro Organogenesis Approach for Ajuga lupulina Maxim

“…In vitro propagation via the multiplication of axillary shoots is an efficient system for mass producing true-to-type plants [ 14 ]. This approach sees the widespread usage of nodal segment explants as reported for Portulaca pilosa [ 15 ], Caryopteris terniflora [ 16 ], and Teucrium scorodonia [ 17 ]. Results along the similar line have been reported for the genus Ajuga .…”

“…TDZ is believed to be the best synthetic cytokinin present for the regeneration of numerous plant systems [ 19 , 20 ]. High cytokinin activity of TDZ inhibits shoot elongation; however, it is conducive to the formation of somatic embryos [ 15 , 21 ]. Whereas, in our study, TDZ induced the fewest shoots with bulk differentiated callus supporting this view.…”

“…In our study, we also reported morphologically similar embryo-like structures (ELSs) induction from the leaf explants. The induction of adventitious shoots and ELSs have been simultaneously induced from explants of Alupulina that has also been found in other species as well, such as Portulaca Pilosa [ 15 ], Metabriggsia ovalifolia [ 21 ], and Camellia nitidissima [ 24 ]. This induction of adventitious shoots or somatic embryo-like shoots was seen on MS medium containing cytokinins (3.0–4.0 mg L −1 BA and TDZ) or along with 0.1 mg L −1 NAA ( Figure 2 c,i).…”

In vitro daylily (Hemerocallis species) bract multiple shoot induction

“…This establishes the bract as a reliable explant for daylily in vitro propagation. The application of TDZ in previous tissue culture studies has often resulted in very effective responses across plant species and superior performances over different other growth regulators (Huang et al, 2020;Chen et al, 2020). Because of the differential level of difficulty to micro-propagate plant species, there is an exhaustive effort to explore a spectrum of plant tissues, including the bract, for their totipotency potential.…”