High frequency in vitro regeneration of adventitious shoots in daylilies (Hemerocallis sp) stem tissue using thidiazuron

Abstract

Background: Daylilies are a lucrative crop used for its floral beauty, medicinal proprieties, landscaping, fire prevention, nutritional value, and research. Despite the importance, daylilies remain extremely challenging for multiplying in vitro. The response difficulty is exacerbated because a few good protocols for daylilies micropropagation are generally difficult to reproduce across genotypes. An efficient strategy, currently applied at Langston University, is to systematically explore individual tissues or organs for their potential to micropropagation. This article is a partial report of the investigation carried out under room environmental conditions and focuses on developing an efficient daylilies in vitro propagation protocol that uses the stem tissue as the principal explant. Results: In less than three months, using thidiazuron, the use of the stem tissue as the in vitro experimental explant was successful in inducing multiple shoots several folds greater than current daylilies shoot organogenesis protocols. The study showed that tissue culture can be conducted successfully under unrestricted room environmental conditions as well as under the controlled environment of a growth chamber. It also showed that splitting lengthwise stem explants formed multiple shoots several folds greater than cross-sectioned and inverted explants. Shoot conversion rate was mostly independent of the number of shoots formed per explants. The overall response was explant and genotype-dependent. Efficient responses were observed in all thidiazuron treatments. Conclusion: An efficient protocol, which can be applied for mass multiple shoots formation using the daylilies stem tissue as the main explant, was successfully developed. This could lead to a broad and rapid propagation of the crop under an array of environmental conditions to meet the market demand and hasten exogenous gene transfer and breeding selection processes.

Cellular, Molecular, and Physiological Aspects of In Vitro Plant Regeneration

“…Figure 1 shows morphology of different stages during plant organogenesis in Nicotiana rustica . Although in vitro regeneration techniques via somatic embryogenesis have been optimized for many crops, some important crop species, such as Hemerocallis sp L. [ 66 ] and Corylus avellana L. [ 67 ], are still difficult to multiply in vitro. Therefore, understanding the physiological, cellular, and molecular mechanisms of plant regeneration is important to address unanswered fundamental questions in cell and developmental biology.…”

Micropropagation of Daylily (Hemerocallis fulva) from Crown-Tip Explants and Assessment of Somaclonal Variation of in Vitro-Propagated Plants Using SCoT Markers

“…Daylily (Hemerocallis fulva) is a profitable plant, which is increasingly popular, mainly due to its uses in the landscape [1], beautiful flowers [2], and medicinal and pharmaceutical uses [3,4]. Like many other economically valuable crops, the daylily is investigated for reliable in vitro mass production.…”

Deciphering the mitochondrial genome of Hemerocallis citrina (Asphodelaceae) using a combined assembly and comparative genomic strategy

“…H. citrina has been proposed as a Chinese herbal medicine in antioxidant, anti-inflammatory, and antidepressant treatments for a long time. Research on H. citrina has mainly focused on morphological assessment (Li et al, 2021b), pharmaceutical properties (Wang et al, 2018), tissue culture (Matand et al, 2020), and circadian flowering rhythm (Ren et al, 2019). In recent years, sequencing information of the cp (Ou et al, 2020) and nuclear (Qing et al, 2021) genomes in H. citrina has been successively obtained and utilized.…”