Axillary Shoot Research Articles

Two Advanced Cryogenic Procedures for Improving Stevia rebaudiana (Bertoni) Cryopreservation.

Cryopreservation is a useful tool for the long-term storage of plant genetic resources, and different cryogenic procedures have recently been developed. The present study focused on the use of the Droplet-vitrification (DV) and V cryo-plate protocol for the cryopreservation of Stevia rebaudiana in vitro-derived apical shoot tips and axillary shoot tips. A preliminary test showed that 90 and 120 min PVS2 (Plant Vitrification Solution 2) treatment significantly reduced the regrowth of the explants before immersion in liquid nitrogen (LN). For both procedures tested, the best osmoprotective condition for obtaining a higher regrowth of cryopreserved explants occurred when explants were PVS2 treated for 60 min. After direct immersion in LN, thawing and plating, the highest regrowth recorded was 80% with DV and 93% with V cryo-plate. Moreover, shoot tips proved to be a more suitable material for Stevia cryopreservation. A satisfactory vegetative regrowth was observed in the subcultures following cryopreservation by DV and V cryo-plate cryogenic procedures.

Cell Quiescence Is the Fountain of Youth in Plants

What determines the rate at which a multicellular organism matures is a fundamental question in biology. In plants, the decline of miR156 with age serves as an intrinsic, evolutionarily conserved timer for the juvenile-to-adult phase transition. However, the way in which age regulates miR156 abundance is poorly understood. Here, we show that the rate of decline in miR156 is correlated with developmental age rather than chronological age. Mechanistically, we found that cell division in the apical meristem is a trigger for miR156 decline. The transcriptional activity of MIR156 genes is gradually attenuated by the deposition of the repressive histone mark H3K27me3 along with cell division. In perennial plants, the quiescent axillary shoot meristematic cells preserve their original epigenetic status at the MIR156 gene loci, thereby contributing to the formation of juvenile zones at the root crown. Our findings thus provide a plausible explanation of why the maturation program of a multicellular organism is unidirectional and irreversible, and uncover a molecular mechanism underlying the unique life-cycle strategy of long-lived perennial plants.

Meta-topolin and liquid medium enhanced in vitro regeneration in Scaevola taccada (Gaertn.) Roxb

Scaevola taccada (Gaertn.) Roxb. is a hemi-sclerophyllous littoral shrub of the family Goodeniaceae. It is a salt-tolerant plant and used in soil reclamation and coastal landscaping programs to control beach erosion. The present article reports a reproducible in vitro regeneration system using meta-topolin (mT) through liquid medium employing nodal segment cultures. The highest number of axillary shoots (5.8 ± 0.29) was differentiated on Murashige and Skoog’s (MS) medium containing meta-topolin (1.5 mg L−1). The amplification of shoots (49.8 ± 0.37) and fresh growth was achieved by recurrent subcultures on liquid MS medium supplemented with 0.25 mg L−1 mT and 0.15 mg L−1 indole-3-acetic acid (IAA) in the presence of additives (50 mg L−1 ascorbic acid + 25 mg L−1 citric acid, adenine sulphate and l-arginine). Rooting and acclimatization was simultaneously achieved using concurrent ex vitro rooting and acclimatization (CEVRA) technique by pulse treating the shoot base with 300 mg L−1 IBA for 5 min. The in vitro developed shoots represented a maximum percentage (100%) of rooting in autoclaved soilrite in a greenhouse. After 2 mo, the plantlets were established in the field with cent percentage survival success. The genetic fidelity analysis using inter simple sequence repeats (ISSR) DNA molecular markers developed maximum of 55 monomorphic bands and revealed the genetic homogeneity of in vitro regenerated plantlets with the mother plant.

Evolutionary and ecological significance of photosynthetic organs inPhyllocladus(Podocarpaceae)

AbstractThe structure of phylloclades and true leaves in Phyllocladus was investigated with emphasis on function, ecology and evolution. Only in the earliest ontogenetic stages are true, needle leaves developed. The earliest phylloclades comprise a fusion product of a shoot axis of the first order and its inserted leaves. Later, this is augmented by the expansion of axillary short shoots from the base of some of the fused leaves. Phylloclades of mature individuals are entire short shoot systems, including leaves and shoots, becoming fused with photosynthetic tissue. These phylloclades represent one of the adaptations for increasing functional photosynthetic area that are present in Podocarpaceae. Such adaptations were probably needed because Podocarpaceae are usually medium-sized trees faced with competition from the ever-expanding angiosperm forests at mid to high latitudes in the Southern Hemisphere from the Late Cretaceous, but especially during the Palaeocene–Eocene, when dense and diverse angiosperm-dominated rainforests were common. The data obtained from living species were compared to those from fossil material of Phyllocladus. Phyllocladus with fully developed phylloclades have been in place since at least the early Cenozoic.

Micropropagation of the potential blueberry rootstock—Vaccinium arboreum through axillary shoot proliferation

Vaccinium arboreum is adapted to soils with low organic matter and high pH. It is considered as a potential blueberry rootstock. The objective of this research was to establish a rapid mass propagation protocol of V. arboreum through axillary shoots proliferation with minimum somaclonal variation. Nodal segments from cuttings were cultured on Driver and Kuniyaki walnut medium (DKW) with different cytokinins for initial culture establishment. DKW, woody plant medium (WPM), and Long and Preece medium (LP) were compared for best shoot proliferation. Zeatin (ZT) concentrations from 0 to 4.56 μM were evaluated for optimizing the concentration. Both in vitro and ex vitro rooting were evaluated. The pH tolerance of in vitro shoots was investigated by adjusting the media pH from 5 to 8.5. Best shoot proliferation was achieved by LP medium supplemented with 2.28 μM ZT and 0.05 μM indole-3-butyric acid (IBA). In vitro shoots proliferated best on medium pH 5, though the shoots could survive on pH 8. All the micropropagated shoots successfully rooted by ex vitro rooting after dipping with auxin. All rooted plantlets acclimatized and grew well in greenhouse. Micropropagation through axillary shoots proliferation is an efficient method to propagate true-to-type V. arboreum in large number for future use as rootstock.

Establishment of in vitro aseptic culture of Philodendron xanadu Croat

ABSTRACT The philodendron is a plant with a high sales price, however, in Mexico there is not enough plant material available for the producers of this ornamental. Therefore, the objective of this research was to establish an in vitro aseptic culture of philodendron, for this, the effect of fungicides and bactericides applied from the transplantation of mother plants to the production and harvest of explants (axillary shoots) for in vitro establishment was evaluated. Two experiments were carried out using MS culture medium; in the second, silver nanoparticles (AgNPs) were added to the culture medium. Both experiments were established in a completely randomized experimental design. It was observed that with the joint action of the sanitizing products in the treatment of mother plants and in the disinfection process, as well as the addition of AgNPs to the culture medium, it was possible to establish an aseptic culture of philodendron. Results show that 2 g L-1 of Agry-Gent Plus 5000® plus 2 g L-1 of Prozycar® in the treatment of mother plants was the one generated the highest percentage of aseptic explants (25.71%) in the first in vitro establishment, while, in the second experiment, the same products plus the addition of AgNPs to the culture medium for seven days generated 100% aseptic explants. The contaminants identified were yeasts, Aspergillus sp. and Penicillium sp.

In vitro large scale clonal propagation of Achyranthes aspera L.: A high value medicinal plant

Achyranthes aspera is an important medicinal plant widely used in indigenous systems of medicine for the treatment of a variety of diseases and disorders. Efficient and reproducible protocols were established for in vitro clonal propagation of A. aspera through axillary shoot proliferation from nodal segments and de novo adventitious shoot formation directly from the leaf and stem explants. Multiple shoot proliferation from nodal segments was achieved on Murashige and Skoog’s (MS) medium supplemented with different concentrations of cytokinins like benzyl aminopurine and kinetin and the best results were achieved on MS medium supplemented with 8.88 μM benzyl aminopurine where 15-16 shoots were initiated after 5-6 weeks. The present material exhibited a high propensity of de novo adventitious root and shoot formation directly from the leaf and stem segments without the intervening callus phase. Direct regeneration of shoots was observed on MS medium supplemented with naphthlene acetic acid (10.74-21.48 μM) alone or in conjunction with benzyl aminopurine or kinetin producing 18-20 shoots. The regenerated shoots were rooted on basal MS medium and the plantlets were successfully acclimatized and established in the field with 80% survival.

Micropropagation of the therapeutic-honey plants

Demand for therapeutic honey is driving establishment of Leptospermum plantations. This study developed micropropagation methods for two species – Leptospermum polygalifolium Salisb. and L. scoparium J.R.Forst. & G.Forst. The study determined how shoot proliferation and adventitious rooting were influenced by the original explant position on the seedling and the concentration of benzyladenine (BA) in the proliferation medium. Hormone-free node culture was highly effective for both species. Nodal explants often formed roots in the absence of BA and developed elongated axillary shoots. Median shoot numbers of 584 and 659 were formed in 31–32 weeks from a single L. polygalifolium or L. scoparium seed, respectively. A low BA dose was effective for callogenesis and shoot proliferation of L. polygalifolium, but not L. scoparium. The median number of shoots produced from a single L. polygalifolium seed was 630 using 2.22-μM BA. This dose induced extremely high shoot numbers in some clones because explants often produced extensive callus and multiple short shoots. Shoots formed adventitious roots without indole-3-butyric acid and plantlets were acclimatised to nursery conditions. The original explant position did not influence shoot proliferation or adventitious rooting. Leptospermum polygalifolium and L. scoparium proved amenable to micropropagation, facilitating rapid establishment of nectar plantations.

Determination of different shoot pruning efficiency for controlling Lasioptera sp. (Diptera: Cecidomyiidae) in protected tomato cultivation and pests visual preferences

Lasioptera sp. is one of the problematic pests in the Mediterranean and Aegean regions where protected tomato cultivation is done in Turkey. The larvae that cause tunnel and deteriorations in the plant’s main stem by feeding on the core part of the body mostly lead to the death of the plant in a dense pest population. Since harmful larvae live in plant tissue and thus are protected against insecticides and biological agents, control of the pest is very crucial. As an alternative method to pest control, the effects of tomato axillary shoot pruning for controlling the pest were examined. For this purpose, while pruning of axillary shoots in tomato plants as recommended in cultural processes, shoots that are cut off from the body completely and stub-pruning sprouts with 3-5 cm length were assessed in the experiment. The study was carried out in Erdemli district of Mersin province in 2015 and 2017. Although it is ensured that the harmful larvae can feed inside stub-pruned shoots left on the body, the larvae could not reach the plant’s main stem and do not cause any damage to the plant. In terms of damaged plants, it was determined that 77.8% and 85.2% of the stub-pruning application are effective in 2015 and 2017, respectively. Additionally, in the study, the attractiveness of visual sticky traps in six different colors including, yellow, black, blue, white, red, and green was investigated. As a result of the study, it was concluded that the colors tested were not sufficient to attract pests.

Investigation on the direct shoot regeneration in date palm CV.Pyarum and possible genetics changes in induced shoots

The palm (Phoenix Dactylifera) is one of important trees, and is economically important in south of Iran. Date palm is propagated by the offshoots, number of which is limited. Therefore, adult Date palms produce shoot tips and axillary shoot meristems through the use of a tissue culture. This study was conducted to perform in -vitro tissue culture direct shoot regeneration and determine the best combination of plant regulators and other conditions. To achieve organogenesis and multiplication directly from shoot tips and axillary shoot meristems of Date palm (Phoenix Dactylifera L. Var Pyarum) was used without callus formation. Direct regeneration of vegetative buds minimizes the risk of somaclonal variation among plant regenerates. Results revealed that MS medium supplemented with 4mg/l of kinetin and 3 mg/l of IAA or 2mg/l of BA and 4 mg/l of NAA was the best formation from shoot tip after 16-20 weeks. Subculture per month was evaluated at following conditions: temperature for growth of 27±1°C during the lighted period and 22±1°C during the dark period.

Assessment of Somaclonal Variations in Embryo-derived Axillary Shoots of Chickpea using Molecular Markers

Background: Somaclonal variation is considered as a source of genetic variation for crop improvement. It has been investigated using cytological, biochemical and molecular techniques.Methods: Genetic stability in the embryo-derived axillary shoots of 4 chickpea genotypes was assessed using eight inter-simple sequence repeat (ISSR) and 19 random amplified polymorphic DNA (RAPD) primers. Result: RAPD primers produced 94 and ISSR primers produced 38 distinct and scorable alleles, with an average of 4.9 alleles for RAPD and 4.75 for ISSR primers. The polymorphic information content (PIC) ranged from 0.36 to 0.90 for RAPD and from 0.50 to 0.87 for ISSR. ISSR recognized a 90%, but RAPD recognized 82% similarity value. No absolute similarity value was between the mother plant and the regenerated shoots for the overall genotypes. At a 90% similarity value, 15 out of the 20 regenerated shoots from ‘Giza 88’ group with their mother plant using ISSR markers; however, 11 regenerated shoots grouped with their mother plant in one central cluster for ‘Giza 4’ using RAPD markers. The observed variations in the total number of polymorphic RAPD and ISSR bands and the number of bands specific to the mother and regenerated shoots, detected intra-clonal variation and genetic instability seem to be genotype-dependent.

In vitro Propagation of Mortiño (Vaccinium floribundum Kunth.)

The disinfected axillary shoots of mortino - a wild plant species were cultured in MS with different concentrations (0.002, 0.05 and 0.1%) of methyl N-(1H-benzimidazol-2-yl) carbamate to develop an in vitro protocol for micropropagation through organogenesis. They were then placed in a concentration matrix (0.1, 1.0 and 10.0 μM) whose factorial design involved BAP and IAA in WPM. Results showed a 100% disinfection at 0.05% concentrations of carbendazim and the combination of IAA and BAP at 10 μM yielded a multiplication factor of 3.35, with rooting after seven weeks. This system showed efficient disinfection, multiplication and yielding an acceptable root system.
 Plant Tissue Cult. & Biotech. 30(2): 167-177, 2020 (December)

A Micropropagation Protocol for the Endangered Medicinal Tree Prunus africana (Hook f.) Kalkman: Genetic Fidelity and Physiological Parameter Assessment.

Prunus africana is an endangered medicinal plant and hence new propagation methods are urgently required to increase its populations. Unfortunately, propagation through seeds is challenging due to its long flowering cycle and recalcitrant seeds. We developed a protocol for micropropagation using nodal segment explants. A woody plant medium supplemented with vitamins, 15 g L−1 sucrose, and 1.0 mg L−1 6-benzylaminopurine (BAP) supported the optimum rate (100%) of axillary shoot initiation. Supplementation with 15 g L−1 sucrose and 1.5 mg L−1 indole-3-acetic acid (IAA) provided the optimum rate (75%) of root initiation. Rooted plantlets were successfully planted in sterilized horticultural soil containing perlite (2:1 v/v) and the survival rate was 98% following acclimatization. The photosynthetic rate assessed using FlourPen FP110 series showed that the ratio of variable fluorescence to maximum fluorescence mean value for in vitro regenerated P. africana (0.830 ± 0.0008) was similar to that of the maternal P. africana plant (0.825 ± 0.005), indicating similarity in their photosynthetic performance; a pivotal process for growth and development. The Fourier transform near-IR (FT-NIR) spectrometer analysis of the in vitro regenerated and the maternal P. africana plant samples exhibited homogeneity in the absorbance peaks at 8,273, 6,344, and 4,938–4,500 cm−1 associated with lipids, starch, and proteins. The genetic fidelity of regenerated plants was confirmed using the randomly amplified polymorphic DNA (RAPD) technique. Our protocol is suitable for use in large-scale P. africana to meet the increasing demands for it in the global market.

Leaf Response to Different Light Spectrum Compositions during Micropropagation of Gerbera Axillary Shoots

The experiment evaluated the influence of different light qualities and 6-benzyladenine (BA) concentration in a medium on the leaf response of multiplied Gerbera jamesonii Bolus ex Hook. f.‘Big Apple’ shoots. Three different light-emitting diode (LED) spectra—100% blue (B), 100% red (R) and red and blue mixture (7:3, RB)—were used, and a fluorescent lamp was used as a control (Fl). Concentrations of BA in Murashige and Skoog (MS) medium were 1, 2.5 and 5 µM. Leaves developed under 100% blue light had a lower frequency of stomata and a smaller area as compared with those from plants exposed to light with red in spectrum. Under 100% red light, the leaf area and the frequency of stomata increased along with growing concentration of BA in the medium. The thickest mesophyll was spotted in the cross-section of leaves exposed to the blue LED light. Leaves developed under the 100% red light had the thinnest mesophyll layers. Increasing concentration of BA in the medium resulted in enhanced leaf blade thickness. The cross-section of leaf vascular bundles was only half of that in petioles. The leaves under the LED combinations had larger vascular bundles than those under fluorescent light. The highest level of photosynthetic pigments was noticed in the leaves grown under LED R and RB lights. Our study demonstrated that 2.5 µM BA and a mixture of blue and red light provided by LED improved leaf quality during multiplication of gerbera shoots.

A Rapid Method for Quantifying RNA and Phytohormones From a Small Amount of Plant Tissue.

Phytohormones are involved in most plant physiological processes and the quantification of endogenous phytohormone levels and related gene expressions is an important approach to studying phytohormone functions. However, the quantification of phytohormones is still challenging due to their extremely low endogenous level in plant tissues and their high chemical diversity. Therefore, developing a method to simultaneously quantify phytohormone levels and RNA would strongly facilitate comparative analyses of phytohormones and gene expression. The present work reports a convenient extraction protocol enabling multivariate analysis of phytohormones and RNA from small amounts of plant material (around 10 mg). This high-throughput ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method demonstrates quantification of phytohormones and their related metabolites from four plant hormone classes: cytokinin, auxin, abscisic acid, and gibberellin. The UPLC-MS/MS method can quantify thirteen phytohormones and their metabolites simultaneously in 14 min. To validate the developed method, we determined the dynamic profiles of phytohormones and gene expressions in small axillary shoot buds in garden pea. This new method is applicable to quantification analysis of gene expression and multiple phytohormone classes in small amounts of plant materials. The results obtained using this method in axillary buds provide a basis for understanding the phytohormone functions in shoot branching regulation.

Micropropagation of Mountain Mulberry (Morus bombycis Koidz.) 'Kenmochi' on Cytokinin-Free Medium.

The aim of the study was to compare two methods of micropropagation of mulberry: single-node culture (“SNC”), and axillary-branching (“AxB”). The experiments were carried out on in vitro cultures for 6 successive passages. The “AxB” cultures were propagated on modified MS medium (+ 25% Ca2+ and Mg2+), supplemented with WPM vitamins, sucrose (30 g L−1), and BA (1.5 mg l-1). The “SNC” cultures were grown on cytokinin-free 1/2 MS (macro- and micronutrients) medium supplemented with WPM vitamins, IBA (0.05 mg l-1), and sucrose (15 g l-1). Both media (pH 5.8) were solidified with agar (7.0 g l-1). Initiation of in vitro cultures from explants taken from adult trees and young, potted plants was feasible on both media. Cultures were established from about 1 cm long nodal explants. Generally “SNC” cultures formed one well rooted, significantly longer axillary shoot with bigger leaves than “AxB” cultures, which developed significantly more shoots and big callus at the explant base. All shoots collected from “SNC” and “AxB” cultures rooted in vivo in peat mixture and developed into similar plantlets. The single-node method based on application of cytokinin-free medium is a good alternative for the axillary-branching method for micropropagation of mountain mulberry (Morus bombycis) ‘Kenmochi”’.

In vitro micropropagation of Basella rubra L. through proliferation of axillary shoots

In vitro micropropagation protocol for Basella rubra regeneration was tried through proliferation of axillary shoots of the potted mature plant. The improved seed germination (70%) was recorded upon 2% urea treatment. The nodal shoot segments from matured potted plant were used to initiate the multiple shoot proliferation. The shoot segments exhibited 70% shoot initiation when cultured on Murashige and Skoog (MS) medium supplemented with Indole-3-acetic acid (IAA) + N6 – Benzylaminopurine (BAP) (0.25 + 2.0 mg/L) and BAP + Kinetin (Kin) (2.0 + 0.5 mg/L) respectively. Multiple shoots (5–6) were obtained on MS medium supplemented with BAP + Kin and IAA + BAP respectively. When compared with silver nitrate (AgNO3) (2–40 µM) and activated charcoal (AC) (0.1–1.0%), the MS medium devoid of any plant growth regulator showed good number of shoots (5.48 ± 2.42), elongation (15.64 ± 2.42 cm) and root length (14.52 ± 2.78 cm). Upon transferring of regenerated microshoots to MS medium, simultaneous elongation of shoots with more shoot number, shoot length and rooting was achieved during four subcultures that carried out at 6 weeks’ interval. The regenerated in vitro shoots showed 100% rooting in MS medium and also in MS medium supplemented with 0.1–1.0% AC. Hundred percent survival of micropropagated shoots well rooted was established successfully under greenhouse condition and the plants were subsequently acclimatized and transferred to the field conditions wherein 90% success rate was noted. We established a novel, and efficient protocol for in vitro B. rubra shoot cultures further multiplication in MS basal medium without any plant growth regulators with 100% elongation and rooting of microshoots that will overcome the use of synthetic hormones for improved micropropagation.

Phytochemical Composition, Antioxidant Capacity, and Enzyme Inhibitory Activity in Callus, Somaclonal Variant, and Normal Green Shoot Tissues of Catharanthus roseus (L) G. Don.

This study aimed to investigate the impact of plant growth regulators, sucrose concentration, and the number of subcultures on axillary shoot multiplication, in vitro flowering, and somaclonal variation and to assess the phytochemical composition, antioxidant capacity, and enzyme inhibitory potential of in vitro-established callus, somaclonal variant, and normal green shoots of Catharanthus roseus. The highest shoot induction rate (95.8%) and highest number of shoots (23.6), with a mean length of 4.5 cm, were attained when the C. roseus nodal explants (0.6–1 cm in length) were cultivated in Murashige and Skoog (MS) medium with 2 µM thidiazuron, 1 µM 2-(1-naphthyl) acetic acid (NAA), and 4% sucrose. The in vitro flowering of C. roseus was affected by sucrose, and the number of subcultures had a significant effect on shoot multiplication and somaclonal variation. The highest levels of phenolics and flavonoids were found in normal green shoots, followed by those in somaclonal variant shoots and callus. The phytochemicals in C. roseus extracts were qualified using liquid chromatography–tandem mass spectrometry. A total of 39, 55, and 59 compounds were identified in the callus, somaclonal variant shoot, and normal green shoot tissues, respectively. The normal green shoot extracts exhibited the best free radical scavenging ability and reducing power activity. The strongest acetylcholinesterase inhibitory effects were found in the callus, with an IC50 of 0.65 mg/mL.

Early topping: an alternative to standard topping increases yield in cannabis production

In commercial settings, cannabis is generally propagated through cuttings, a process referred in the industry as cloning. Some producers perform either topping or fimming to trigger the production of axillary shoots, which will enhance the number of flowers per plants and thus increase the yield of the cannabis plants. Topping or fimming is generally performed after the cuttings have been transferred to rooting media for two weeks. We have tested a new method to increase the shoot number per plant. The modification of the standard topping method consist of performing the topping on mother plants, prior to taking the cuttings for cloning, and the cuttings are taken one week after the topping is performed. The resulting plantlets develop axillary shoots much faster and the time of production from cuttings to harvesting is decreased by 7-10 days. The method proposed herein requires minimal adjustment to the existing workflow and the plants produce as much as when standard topping is performed. Moreover, this method cuts backs on the production time and nearly two weeks are saved compared to the standard topping procedure since the plantlets do not need to recover after topping. Application of this new procedure results in faster production time and ultimately enhanced productivity.

Features of the growth and development of <i>Lycopus americanus</i> Muhlenberg. in the Moscow region

One of the main tasks of botanical gardens is to create and maintain biological collections. There are 5 types of Lycopus in the biological collection of «All-Russian research Institute of medicinal and aromatic plants». One of them is the Lycopus americanus Muhlenberg ex W. P. C. Bart., was the object of this work, as the most difficult in cultivation. In nursery 1-4 years of vegetation researches of growth and development of a Lycopus americanus were carried out. Seeds of Lycopus americanus were received by the exchange Fund from Canada. Sowing was carried out in May 2016 inthe conditions of protected soil in pallets 7×7 cm. Seedlings were grown for two months at a temperature of +18+20 °С and illumination of 1000-1200 lux. In the first decade of July, the nursery was laid with 60-day seedlings according to the scheme 20×60 cm. The area of the plot is 0.8 m2, the repetition is fourfold. Accounting of indicators and processing of results were carried out according to standard methods. Experience in vegetative propagation of Lycopus americanus (2018-2019) got them out from the mother plant and according to the scheme experience, after dividing and planting these divided roots once watered with a solution of homeopathic preparation "Arnica C200" in a concentration of one granule/5 l of water, a flow rate of 5 l/ m2(experiment 1). Of experiment 2, plants after transplantation were once watered with a solution of lactose (milk sugar), the granules of which are filler for homeopathic preparations. The concentration of the solution in option 2 is 1 granule /5 lof water. Control plants were watered with water in the same volume. In the course of the studies it was revealed that the most significant increase in height have plants of the 2nd year of vegetation. The growth decreases with age and in 4-year-old plants reaches minimum. During the season, the greatest increase in height occurs in July and August (in the stalk stage). Watering with a solution of the homeopathic drug "Arnica C200" (experiment 1) during vegetative reproduction of Lycopus americanus causes an increase in height in the first year of vegetation (from 60 days from transplantation) by 30% - 36%. The number of axillary shoots in treated plants by the end of the growing season exceeded the control by 1.6-1.8 times. The dry land mass of treated plants (experiment 1) increased by 34% relative to control group. The treated plants showed an increase in the size of tubers with buds of renewal relative to the control group. The dry mass of the underground part of the treated plants of Lycopus americanus (experiment 1) us by the end of the growing season exceeded that of the control plants by 21%. The average dry mass of 1 tuber at the end of the growing season was 0.63±0.061 gin control plants and 1.17±0.112 gin experimental samples. It is possible to grow Lycopus americanus as a long-term culture in theMoscowregion. The largest increase in biomass of the grain falls on the second year of vegetation. Starting from the third year of vegetation, it is advisable to propagate the plant by dividing the rhizomes in the spring. The homeopathic preparation "Arnica C200" as growth regulator well proved at vegetative reproduction of a Lycopus americanus . Its use causes excessive buildup of Lycopus americanus - storing tubers with the buds of renewal