In Vitro Segregation of Tetraploid and Octoploid Plantlets from Colchicine-induced Ploidy Chimeras in Echinacea purpurea L.

Abstract

<jats:p><jats:italic>Echinacea purpurea</jats:italic> L. is one of the important ornamental and medicinal plant species. Ploidy manipulation is a valuable tool for improving plant quality or production in <jats:italic>E. purpurea</jats:italic> as well as in many other plants. To study the segregation of pure ploidy plantlets from colchicine-induced ploidy chimeras in <jats:italic>E. purpurea</jats:italic>, we used a chimera plantlet that consisted of 1.93% diploid, 35.04% tetraploid, and 63.03% octoploid cells as the source material for experiments. The results showed that three factors significantly influenced the segregation, i.e., the component ratios of different ploidy cells in the chimera, the number of sequential passages, and the methods of segregation culture of the chimera plantlets. Other factors, such as explant types (i.e., leaf, petiole, or root) and 6-benzyladenine (BA) concentrations (i.e., 0.2, 0.4, 0.8, and 1.2 mg·L<jats:sup>−1</jats:sup>) occasionally influenced the segregation. Pure chromosome-doubled polyploids are not easily obtained in various plant species, so segregation culture of ploidy chimeras may potentially be more effective. The morphological characteristic and content of cichoric acid were compared among diploid, tetraploid, and octoploid plants. Results indicated that tetraploid and octoploid plants had more stunted growth, larger stomata, lower stomata frequency, more chloroplast number in guard cells, and higher cichoric acid content than original diploid lines.</jats:p>

Induced autopolyploidy—a promising approach for enhanced biosynthesis of plant secondary metabolites: an insight

“…Similar opinions of modulations in metabolism favouring plant species adaptability were opined by Kumar [82]. Li et al [28] in their findings in Echinacea purpurea reported cichoric acid enhancement through tetraploid and subsequent octaploid induction. From the results, it can be deduced that the rate of increment in metabolite production increases in tetraploids and is further improved in octaploids.…”

“…Such predisposition presumably improved seed germination and in process exposed the protruded shoot apical meristems to colchicine. In terms of exposure time, the longest duration was recorded as 37 days in Echinacea purpurea L. [ 28 ], wherein colchicine was added to the basal media resulting in high frequency tetraploids and octaploids along with augmented cichoric acid production. Addition of antimitotic agents to the basal media increased the exposure time which resulted in higher ploidy level in individual plants.…”

“…(dissolved in 2% DMSO)➔ sterile H 2 O washing Shoot tip Colchicine; 0.3%; 12 h Diploid➔tetraploid (2n=4x=56) Increase in betulinic acid (69.73%), oleanolic acid (42.76%), ursolic acid (140.67%) [ 25 ] Stevia rebaudiana Bertoni Treatment in field condition NM Colchicine; 2.5%; NM Diploid➔tetraploid (2n=4x=44) Increase in rebaudioside-A (6.21%) [ 26 ] Colchicine; 1.50%; NM Mixoploid Increase in steviosisde (13.50%) Tetradenia riparia Submerged in colchicine soln. Seed Colchicine; 0.01 g/l; 24 h Diploid➔tetraploid (2n=4x=) Increase in essential oi production (3.5-fold) [ 27 ] Echinacea purpurea L. MS + 0.4 mg/l BA + 0.01 mg/l NAA + Colchicine Petiole Colchicine; 100 mg/l; 37 d Diploid➔tetraploid (2n=4x=44) Tetraploid➔octaploid (2n=8x=88) Increase in cichoric acid content in octoploid (13.76 and 29.84 mg/g) and tetraploid (10.38 and 22.32 mg/g) than diploid plantlets (8.21 and 18.42 mg/g) aboveground and underground parts, respectively [ 28 ] Miscanthus × giganteus NM NM Colchicine; NM; NM Triploid➔hexaploid (2n=6x=114) Lower phenolic compounds in hexaploids (1266 μg/g and 1349 μg/g) than triploid (1570 μg/g and 2268 μg/g) [ 29 ] Lippia integrifolia (MS + 2.2 μM BA) + colchicine Nodal segment Colchicine; 0.01%; 15 d Diploid➔tetraploid (2n=4x=72) Increase in total monoterpene (9%) [ 30 ] Pogostemon cablin MSL + colchicine➔ shaking at 100 rpm at 25°C Cluster bud Colchicine; 0.05%; 72 h Tetraploid➔octaploid (2n=8x=128) Increase in patchoulic alcohol (2.6-fold) [ 31 ] Chamaemelum nobile L. MSL + 1 μM NAA + 0.5 μM BAP + Colchicine; 25 °C; Dark for 12 h Callus Colchicin...…”

Polyploidy in Industrial Crops: Applications and Perspectives in Plant Breeding

“…Slower growth rates, especially in the early stages, may be due to slower rates of cell division, reduced metabolic rate or lower amounts of growth hormones, among other things [106]. Tetraploids with initial slow growth may include, for example, A. vera [106], A. sativum [112], S. viminalis [75] or E. purpurea [117].…”

“…This was due to modification of gene expression involving repression and/or derepression of genes of the phenolic compound biosynthesis pathway [126]. Studies on the relationship between ploidy level and cichoric acid content in E. purpurea were conducted by Li et al [117]. The obtained results indicated that the content of cichoric acid in the aboveground and underground parts of octoploids of E. purpurea was higher than in tetraploid and diploid seedlings.…”