<i>In Vitro</i> Polyploid Induction and Establishment of a Clone for <i>Cyclocodon lancifolius</i> (Roxb.) Kurz

Abstract

The purpose of this experiment is to select Cyclocodon lancifolius (Roxb.) Kurz strain with a high yield and quality to enhance environmental tolerance. Therefore, we report the first case of polyploid induction in C. lancifolius. The treatment of seed and in vitro shoot tips with colchicine was explored as a means of inducing polyploid, and polyploidy was effectively identified by chromosome counting. After successful induction of polyploid, the optimized in vitro culture for polyploid plants was investigated via a complete combination experiment. The results showed that seeds were not suitable for polyploid induction. The shoot tips were treated with 0.05% colchicine solution for 36 h and then transferred to Murashige and Skoog (MS) medium supplemented with 0.1 mg L 1 6-benzylaminopurine (6-BA), 1.0 mg L 1 α-naphthaleneacetic acid (NAA) and 0.05% colchicine for 60 h. Finally, rooting culture was conducted in the above medium without colchicine, yielding the highest induction rate (25.42%), without chimerism. Compared with diploid plants, autotetraploid plants had more distinctive characters, such as larger and darker green leaves, more obvious veins, thicker stems, and more developed root systems. Furthermore, in MS medium supplemented with 1.0 mg•L 1 NAA and 0.01 mg•L 1 6-BA, tetraploid shoots formed complete plantlets through one-step culture, with above 7.0 multiplication coefficient and 100% rooting rate. The survival rate was 100%. The induction system for the autopolyploid of C. lancifolius was successfully established, which provided an experimental basis for breeding heredity and variety improvement.

In vitro tetraploid induction and plant regeneration of Pinellia ternata, a pearl-like herb

“…Effect of material choice on chromosome doubling Importantly in uencing the polyploid induction process was the type of plant material, and tissues or organs with vigorous cell division were generally regarded as the most suitable induction material (Li et al 2018). Seeds are less functionally differentiated, most cells divide at a more uniform rate, and their cells are subject to similar effects when treated with growth inhibitors, so chimera formation is reduced or prevented (Xi et al 2021). However, some species were not suitable for doubling using seeds, and chromosome doubling was not successfully achieved in C. lancifolius (Roxb.)…”

“…However, some species were not suitable for doubling using seeds, and chromosome doubling was not successfully achieved in C. lancifolius (Roxb.) Kurz and Lepidium sativum L. even when the seed coat was removed and germinated seeds were used; this phenomenon may occur because the seeds of these plants were insensitive to colchicine, or it may be that seeds were stimulated by colchicine and triggered their dormancy mechanism (Aqafarini et al 2019;Xi et al 2021). Simultaneously, the seed induction polyploid induction rate was low, the number of seeds required was large, and survival and propagation after successful seed doubling were more challenging, so successful use of seed induction autotetraploid was reported less frequently (Abdoli et al 2013;Pei et al 2019).…”

“…Changes in endogenous hormone concentrations are likely to inhibit or prevent the formation of microscopic tubers in the procambium layer of leaf vascular bundles (Swarup et al 2008;Klimešová et al 2009). In C. lancifolius, the level of cytokinin in the medium of tetraploid plants was 10 times lower than in the medium of diploid plants, and tetraploid plants were able to regenerate without passing through a callus and achieved simultaneous proliferation and rooting (Xi et al 2020;Xi et al 2021). We modi ed the medium optimal for culture of diploid and reformulated the exogenous hormone concentration for orthogonal proliferation experiments to obtain a new medium suitable for the growth and development of autotetraploid P. ternate.…”

Polyploid Induction and Identification of Begonia × benariensis

“…When plants are identified for ploidy, they can be roughly screened using external morphology first, and morphological identification is a more common and simpler identification method for polyploidy. Generally, polyploid plants are larger than normal plants, with broad and thick leaves, thick stems, larger floral organs, and other morphological characteristics [12][13][14]. The gigantism of organs in the polyploid plants is an important characteristic, but plants with hypertrophied organs are not always polyploids, and not all polyploids are definitely hypertrophied.…”