Production Of Adventitious Roots Research Articles

Assessment of Morphological Diversity and Vegetative Growth Parameters of Fifteen Betel Vine Varieties Cultivated Along the Odisha Coast

Betel vine (Piper betle) is a tropical evergreen plant renowned for its cultural and medicinal significance. With origins in Southeast Asia, its heart-shaped leaves, vibrant colors and aromatic properties contribute to its widespread cultivation. The study investigates the morphological diversity and vegetative growth parameters of fifteen betel vine varieties cultivated along the Odisha coast, with a focus on vine elongation, leaf dimensions, internodal length, leaf area, weight of fresh leaves, number of adventitious root production and the number of leaves per meter of vine. The results revealed significant variation among the varieties. Notably, vine elongation ranged from 39.5 to 68.8 cm/month, with the Golabandha varieties showing the highest rate. Leaf length varied from 8.84 to 20.24 cm, and the Chandrakana varieties displayed the longest leaves. Leaf breadth ranged from 4.46 to 15.3 cm, with the widest leaves found in Chandrakana varieties. Internodal length varied from 3.06 to 6.46 cm, with Gunthuni having the lowest internodes. Leaf area ranged from 38.04 to 177.37 cm2, with Chandrakana exhibiting the largest leaf area. Weight of fresh leaves varied significantly, with Chandrakana and Ralaba varieties having the highest and lowest weights, respectively. Cluster analysis grouped varieties based on their morphological characteristics, revealing distinct clusters related to leaf dimensions and growth parameters. Understanding the morphological diversity of betel vine varieties is crucial for identifying the superior varieties for sustainable cultivation and ensuring the quality of this culturally and economically significant crop.

Developing an in vitro elicitation strategy for specialized secondary metabolites production in adventitious root cultures of Primula veris subsp. veris

The demand for new sources of bioactive plant secondary metabolites (SMs) with importance as pharmaceutical and food additives, cosmetics and flavors, have emerged as rising scientific topic in parallel to the protection of natural habitats due to overexploitation and decreasing of biodiversity. Cowslip (Primula veris L. subsp. veris) is a perennial medicinal plant in which pharmaceutically important SMs such as phenolic acids glycosides (primulaverin, primeverin) and triterpene saponins (primulic acid I and II) are produced in the roots and aerial parts. These metabolites serve as quality markers for the evaluation of raw materials used for the production of expectorant and diuretic drugs. Alternatively to traditional soil-cultivation of whole plants, in vitro adventitious root production systems have the potential for elevated and stable production of plant SMs through elicitation processes. Additionally, these systems have an advantageous perspective from ecological and economical aspect comparing with conventional method for mass production of valuable compounds. In the present study eight abiotic elicitors [salicylic acid (SA), cazeine hydrolysate (CH), L-proline, silver nitrate (AgNO3), cobalt chloride (CoCl2), sucrose, jasmonic acid (JA) and putrescine], under a 60-day culture period into 250 mL flasks were tested. Afterwards, the following three elicitors applied in single (100 mg/L CH, 100 mg/L L-proline, 25 μM JA) or combinations (JA + CH, JA + L-proline), under two exposure times (30 and 60 days). The results showed that primeverin [35.7 mg/g dry weight (DW)], and cumulative phenolic acids glycosides (52.9 mg/g) content, yield index (YI) of primeverin (97.4 mg of pure dry extract), cumulative phenolic acids glycosides (144.4 mg), primulic acid I (37.2 mg), primulic acid II (9.1 mg) and cumulative saponins (45.4 mg), as well as root fresh biomass growth rate (× 10.2-fold), and root DW (2.7 g) were promoted after elicitation with 100 mg/L L-proline for 60 days. Primulaverin (23.6 mg/g), primeverin (14.4 mg/g) and the cumulative phenolic acids glycosides (38.1 mg/g) content was considerably maximized after treatment with 25 μM JA for 30 days. Combined elicitation of roots with 25 μM JA + 100 mg/L L-proline for 30 days, indicated the highest content in primulic acid II (5.9 mg/g), cumulative saponins (22 mg/g), while primulic acid I represented the highest content under 100 μM JA for 60 days (27 mg/g). Among the eight elicitors tested, L-proline, JA, and L-proline + JA proved to be the most beneficial treatments for SMs production. Following that, root fresh biomass growth rate (× 8.1), content, and YI of primulaverin (14.3 mg/g, 149.1 mg), primeverin (0.3 mg/g, 3.2 mg), cumulative phenolic acids glycosides (14.6 mg/g, 152.3 mg), primulic acid I (10.3 mg/g, 93.3 mg), primulic acid II (2.5 mg/g, 19.2 mg), and cumulative saponins (12.8 mg/g, 112.5 mg) were considerably higher after 90 days of culture in a 2 L balloon bubble type bioreactor system than after 60 days. Elicitor type, elicitor concentration, and elicitation exposure duration are factors that play a key role in the production of SMs. In the present study, the importance of abiotic elicitation strategies, and bioreactor systems which are novel in the scale-up process, on adventitious root in vitro cultures of P. veris subsp. veris have been discussed in detail and are highlighted for the first time. The production systems applied herein lay the possibilities for the large-scale manufacturing of specialized plant-derived SMs including triterpene saponins and phenolic acid glycosides, presenting commercial applications due to higher root biomass and bioactive compounds productivity obtained.

The Impact of Auxin and Cytokinin on the Growth and Development of Selected Crops

With a very diverse structure and small molecules, phytohormones are regulators of plant growth and development. Despite the fact that they are synthesized by plants in small quantities, they are highly active physiologically. According to their action, phytohormones can be divided into two categories, as either activators of plant growth and development or as inhibitors, with auxins and cytokinins belonging to the former group. Auxins are synthesized by plants in the apical meristems of shoots, but also in young leaves, seeds, and fruits. They stimulate the elongation growth of shoots and initiate the production of adventitious and lateral roots. Cytokinins, in turn, are formed in root tips and in unripe fruits and seeds. These hormones are responsible for stimulating the growth of lateral shoots, they also stimulate cytokinesis and, consequently, cell division. The aim of this review paper is to present the progress of the research on the effect of selected auxins and cytokinins on crops, considering the prospect of using them in plant growing methods.

Differences in eco-physiological responses to the removal of adventitious roots between Syzygium nervosum A. Cunn. ex DC. and Syzygium cumini (L.) Skeels saplings under waterlogging

Key messageThe production of adventitious roots partially counteracts the negative effects of waterlogging on the growth of Syzygium nervosum A. Cunn. ex DC. and Syzygium cumini (L.) Skeels. S. cumini was more responsive and suffered from larger negative effects than S. nervosum after the removal of adventitious roots.ContextAdventitious roots contain gas channels and functionally replace or compensate for the loss of primary roots that usually decay during waterlogging. However, the importance of adventitious roots on growth in waterlogged woody plants varies with species. Therefore, there has been some controversy about whether adventitious roots have beneficial effects on the growth of waterlogged plants.AimsWe assessed whether S. nervosum and S. cumini differentially responded to the ablation of adventitious roots during waterlogging and whether compensatory responses occurred in the primary roots in both species.MethodsS. nervosum and S. cumini saplings were subjected to waterlogging and adventitious root removal for 120 days, and morphological, physiological, biochemical parameters, and biomass were recorded.ResultsAll plants survived waterlogging, and produced adventitious roots at the shoot base. Waterlogging had negative effects on the growth of both species, but the effect was more severe in S. cumini than in S. nervosum as seen from the values of comprehensive evaluation and total biomass. However, S. nervosum compensated for the ablation of adventitious roots with increased primary root dry mass, primary root activity, total root length, root tip number, and peroxidase activity.ConclusionsS. nervosum with a high proportion of adventitious roots would be at an advantage during waterlogging. The removal of adventitious roots was detrimental to the growth of both species, but S. nervosum exhibited less damage than S. cumini due to its compensatory physiological responses and its primary roots.

Species-Specific Secondary Metabolites from Primula veris subsp. veris Obtained In Vitro Adventitious Root Cultures: An Alternative for Sustainable Production

Primula veris subsp. veris L. is a perennial herbaceous and medicinal plant species the roots and flowers of which are a source of valuable pharmaceutical raw materials. The plant tissues are used to produce expectorant and diuretic drugs due to their high content of triterpene saponins and phenolic glycosides. Underground roots of P. veris can be obtained only through a destructive process during the plant’s harvesting. In the present study, an in vitro adventitious root production protocol was developed as an alternative way of production, focused on four species-specific secondary metabolites. Root explants were cultured in Murashing & Skoog liquid medium supplemented with 5.4 μM α-naphthaleneacetic acid, 0.5 μM kinetin, L-proline 100 mg/L, and 30 g/L sucrose, in the dark and under agitation. The effect of temperature (10, 15 and 22 °C) on biomass production was investigated. The content of two flavonoid compounds (primeverin and primulaverin), and two main triterpene saponins (primulic acid I and II) were determined after 60 days of culture and compared with 1.5-year-old soil-grown plants. The accumulated content (mg/g DW) of bioactive compounds of in vitro adventitious roots cultured under 22 °C was significantly higher than the other two temperatures of the study, being 9.71 mg/g DW in primulaverin, 0.09 mg/g DW in primeverin, 6.09 mg/g DW in primulic acid I, and 0.51 mg/g DW in primulic acid II. Compared to the soil-grown roots (10.23 mg/g DW primulaverin, 0.28 mg/g DW primeverin, 17.01 mg/g DW primulic acid I, 0.09 mg/g DW primulic acid II), the in vitro grown roots at 22 °C exhibited a 5.67-fold higher content in primulic acid II. However, primulic acid I and primeverin content were approximately three-fold higher in soil-grown roots, while primulaverin content were at similar levels for both in vitro at 22 °C and soil-grown roots. From our results, tissue culture of P. veris subsp. veris could serve not only for propagation but also for production of species-specific secondary metabolites such as primulic acid II through adventitious root cultures. This would therefore limit the uncontrolled collection of this plant from its natural environment and provide natural products free from pesticides in a sustainable way.

Inbreeding depression changes with stress response over time in flooded Mimulus guttatus

Inbreeding usually reduces offspring fitness (‘inbreeding depression’, ID), and may affect the plasticity of functional traits involved in the response to stress. ID is often found to increase under stress, but there are also reports of no effects or even a reduction of ID under stress. One reason for this variation that has received little attention may be related to different concepts of stress. In particular, the magnitude of ID may be unrelated to the effect of an environment on fitness (evolutionary stress concept), but increase particularly during the ‘alarm phase’ after a stress has been initiated (physiological stress concept). We clonally replicated inbred and outbred Mimulus guttatus plants, for which ID was known to increase under flooding. We exposed the clonal replicates to control and flooding conditions and harvested replicates of each genotype after two, six and 11 weeks of growth. As functional traits related to stress response we measured chlorophyll fluorescence, root mass and the production of stolons and adventitious roots. As fitness estimates we measured biomass and flower number, and we pollinated a subset of plants and grew a second generation of plants under control and flooding conditions to calculate multiplicative fitness. Overall, M. guttatus proved to be very flooding-tolerant. Chlorophyll fluorescence (Fv/Fm) was not influenced by flooding, but decreased with leaf age and increased after fertilization. At the end of the experiment, biomass and flower number (F1 generation) as well as multiplicative fitness (including performance in the F2 generation) were even higher under flooding than under control conditions. Flooding reduced the root mass in the pots, but increased the production of stolons and floating roots. Plasticity in these traits can be regarded as beneficial, although selection gradient analysis failed to identify plasticity in stolon number as adaptive. Only two functional traits were influenced by an interaction between flooding and inbreeding, early stolon length (suggesting a reduced flooding escape response of inbred plants) and root tissue density of floating adventitious roots (suggesting a reduced aeration of the roots of inbred offspring). ID in fitness-related traits was higher under flooding, but its magnitude changed strongly over the course of the experiment. ID under flooding was particularly high after two weeks (δ = 0.42 vs. 0.05 in the control), suggesting sensitivity of inbred plants to the initiation of flooding (‘alarm phase’ of stress response). This effect had disappeared after 6 weeks when plants had acclimated to ongoing flooding. However, under flooding ID increased again after 11 weeks, this time because outbred plants grew much better under flooded than control conditions, and the same pattern was found for the multiplicative fitness function (δ = 0.68 under flooding vs. 0.36 in the control). Our results suggest that ID was higher under flooding, but not because this environment was generally more stressful. Instead, at an early stage ID increased because inbred offspring was more sensitive to the physiological stress after the initiation of flooding (‘alarm phase’), whereas at a late stage ID increased because outbred offspring was more capable of exploiting the favourable flooding conditions. In general, our results show that phenotypic plasticity may often be robust against the effects of inbreeding. Moreover, ID may increase in particular under conditions of physiological stress, during which many stress-specific genes are expressed, whereas ID may not necessarily increase under constant poor conditions that reduce fitness, even if the stress is very strong in the evolutionary sense.

Endocormic roots: transforming death into life

ABSTRACT There is a substantial literature on the production of adventitious roots by the trunks and branches by intact trees but one type that has received very little attention are the endocormic roots that develop inside the trunks of old trees with extensive heart rot. They were first described in 1853 and are an indicator of the senescent phase of a tree’s life span. Endocormic roots are produced by wound-wood that comes in contact with its own rotten heartwood. As the tree’s core hollows out, endocormic roots can grow down through the trunk into the soil where they have the potential to produce a new root system and thicken into columns that support the hollow stem. While the formation of endocormic roots has been documented in many angiosperms, it is a relatively uncommon phenomenon that develops mainly in ancient trees that have experienced extensive branch loss due to natural disturbances or pollarding. A parallel term, epicormic roots, is proposed to describe adventitious roots produced by the trunk or branches of a tree that come in contact with the soil.

Scale-up production of Rehmannia glutinosa adventitious root biomass in bioreactors and improvement of its acteoside content by elicitation

Rehmannia glutinosa is an important medicinal crop that has been widely used globally to treat various ailments such as hematinic deficiencies, diabetes, and adrenal disorders. To provide a sustainable supply to meet large demands, alternative cultivation methods, apart from conventional ones, are indispensable. This study developed an optimized condition for R. glutinosa adventitious root culture and a scale-up production system using a bioreactor. A woody plant medium enriched with vitamins, 30 g/L sucrose, and 2.0 mg/L 1-naphthaleneacetic acid (NAA) supported the optimum growth rate of adventitious roots (growth index of 25.67). The application of methyl jasmonate (MeJa) at a concentration of 200 μM showed the best enhancement of acteoside biosynthesis, with an approximately 2.53-fold increase (14.37 mg/g dry weight [DW]) compared with the control (5.67 mg/g DW). However, all treatments with MeJa and salicylic acid reduced the biomass of R. glutinosa adventitious roots compared with control. To validate the optimized protocol, the culture system was scaled up by comparing shake flask cultures with 2- and 20-L balloon type (air lift) bubble bioreactors (BTBB) along with elicitation using 200 μM MeJa. The 20-L BTBB cultures produced good-quality R. glutinosa roots with higher biomass (15.94 g DW), acteoside content (22.13 mg/g DW), and antioxidant activity (84.22 %) than shake flask cultures. In addition, fourier transform near-IR (FT-NIR) analysis showed no significant difference in the chemical composition of the in vitro adventitious roots and those that were commercially available. Thus, these findings will provide a basis for the development of large-scale R. glutinosa adventitious root production to meet the demands of pharmaceutical and oriental medicine industries without affecting its availability in nature.

Depicting the molecular responses of adventitious rooting to waterlogging in melon hypocotyls by transcriptome profiling.

The online version contains supplementary material available at 10.1007/s13205-021-02866-w.

Floodwater Depth Causes Different Physiological Responses During Post-flooding in Willows.

Willows are widely planted in areas under risk of flooding. The physiological responses of willows to flooding have been characterized, but little is known about their responses during the post-flooding period. After the end of the stress episode, plants may modify some traits to compensate for the biomass loss during flooding. The aim of this work was to analyze the post-flooding physiological responses of willow under two different depths of stagnant floodwater. Cuttings of Salix matsudana NZ692 clone were planted in pots in a greenhouse. The experiment started when the plants were 2 months old with the following treatments: Control plants (watered to field capacity); plants partially flooded 10 cm above soil level (F10) and plants partially flooded 40 cm above soil level (F40). The flooding episode lasted 35 days and was followed by a recovery period of 28 days (post-flooding period). After the flooding period, height, diameter and total biomass were higher in F10, while F40 plants showed an increase in plant adventitious root production and leaf nitrogen content. During the post-flooding period, the photosynthetic rate, nitrogen, chlorophyll and soluble sugar contents were significantly higher in leaves of F40 than in Control and F10 treatments. Stomatal conductance and specific leaf area were higher in the previously flooded plants compared to Control treatment. Plants from F10 treatments showed a higher growth in height, root-to-shoot ratio, and carbon isotope discrimination than F40, while the opposite occurred for growth in diameter, vessel size and leaf area. We conclude that depth of floodwater not only causes different responses during flooding, but that its effects are also present in the post-flooding recovery period, affecting the growth and physiology of willows once the stress episode has ended. Even when flooding impacted growth negatively in F40, in the post-flooding period these plants compensated by increasing the photosynthetic rate, plant leaf area and xylem vessel size. Willows endurance to flooding is the result of both responses during flooding, and plastic responses during post-flooding.

The responses of Spinifex littoreus to sand burial on the coastal area of Pingtan Island, Fujian Province, South China

ABSTRACT The adaptive capacity of psammophytes to sand burial is crucial for the ecological restoration of coastal dune systems. The responses of Spinifex littoreus to different sand burial depths and levels were examined on the coast of Pingtan Island, Fujian Province, South China. The results indicated that, compared with the control group (CG), sand burial on the S. littoreus stolons had no significant impact on the vertical growth of its conjoint ramets. However, the horizontal growth of S. littoreus stolons was stimulated and significantly increased in half-intense (HI) and complete-intense (CI) sand burial treatments by 24.56% and 40.79%, respectively. Throughout the experiment, about 96% of adventitious roots were observed on the base section of stolons, while no roots in the control group (CG). After 20-day artificial sand burial treatments, the dry weight ratio between stem and leaf of S. littoreus was decreased in all three sections of stolons, especially for the top sections. Overall, S. littoreus can adapt to the complete and intense sand burial in growing season by rapid growth of stolons, abundant production of adventitious roots on the stolon base, and more germination of leaves on the stolon top.

Restructuring the Cellular Responses: Connecting Microbial Intervention With Ecological Fitness and Adaptiveness to the Maize (Zea mays L.) Grown in Saline-Sodic Soil.

Salt stress hampers plant growth and development. It is now becoming one of the most important threats to agricultural productivity. Rhizosphere microorganisms play key roles in modulating cellular responses and enable plant tolerant to salt stress, but the detailed mechanisms of how this occurs need in-depth investigation. The present study elucidated that the microbe-mediated restructuring of the cellular responses leads to ecological fitness and adaptiveness to the maize (Zea mays L.) grown in saline–sodic soil. In the present study, effects of seed biopriming with B. safensis MF-01, B. altitudinis MF-15, and B. velezensis MF-08 singly and in consortium on different growth parameters were recorded. Soil biochemical and enzymatic analyses were performed. The activity and gene expression of High-Affinity K+ Transporter (ZmHKT-1), Sodium/Hydrogen exchanger 1 (zmNHX1), and antioxidant enzymes (ZmAPX1.2, ZmBADH-1, ZmCAT, ZmMPK5, ZmMPK7, and ZmCPK11) were studied. The expression of genes related to lateral root development (ZmHO-1, ZmGSL-1, and ZmGSL-3) and root architecture were also carried out. Seeds bioprimed with consortium of all three strains have been shown to confer increased seed germination (23.34–26.31%) and vigor indices (vigor index I: 38.71–53.68% and vigor index II: 74.11–82.43%) as compared to untreated control plant grown in saline–sodic soil at 30 days of sowing. Results indicated that plants treated with consortium of three strains induced early production of adventitious roots (tips: 4889.29, forks: 7951.57, and crossings: 2296.45) in maize compared to plants primed with single strains and untreated control (tips: 2019.25, forks: 3021.45, and crossings: 388.36), which was further confirmed by assessing the transcript level of ZmHO-1 (7.20 folds), ZmGSL-1 (4.50 folds), and ZmGSL-3 (12.00 folds) genes using the qPCR approach. The uptake and translocation of Na+, K+, and Ca2+ significantly varied in the plants treated with bioagents alone or in consortium. qRT-PCR analysis also revealed that the ZmHKT-1 and zmNHX1 expression levels varied significantly in the maize root upon inoculation and showed a 6- to 11-fold increase in the plants bioprimed with all the three strains in combination. Further, the activity and gene expression levels of antioxidant enzymes were significantly higher in the leaves of maize subjected seed biopriming with bioagents individually or in combination (3.50- to 12.00-fold). Our research indicated that ZmHKT-1 and zmNHX1 expression could effectively enhance salt tolerance by maintaining an optimal Na+/K+ balance and increasing the antioxidant activity that keeps reactive oxygen species at a low accumulation level. Interestingly, up-regulation of ZmHKT-1, NHX1, ZmHO-1, ZmGSL-1, and ZmGSL-3 and genes encoding antioxidants regulates the cellular responses that could effectively enhance the adaptiveness and ultimately leads to better plant growth and grain production in the maize crop grown in saline–sodic soil.

Heterologous expression of Arabidopsis thaliana rty gene in strawberry (Fragaria \xd7 ananassa Duch.) improves drought tolerance

BackgroundStrawberry (Fragaria × ananassa Duch.) is an important fruit crop worldwide. It was particularly sensitive to drought stress because of their fibrous and shallow root systems. Mutant rty of Arabidopsis thaliana ROOTY (RTY) results in increased endogenous auxin levels, more roots, and shoot growth. It is still unclear whether the rty gene improves stress tolerance in strawberry.Resultsrty gene was isolated from Arabidopsis thaliana and placed under the control of the cauliflower mosaic virus (CaMV) 35S promoter in the pBI121-rty binary vector carrying the selectable marker of neomycin phosphotransferase II (NPT II). Seven transgenic lines were confirmed by PCR and western blot analysis. Accumulations of IAA and ABA were significantly increased in the transgenic plants. The endogenous IAA contents were 46.5 ng g− 1 and 66.0 ng g− 1in control and transgenic plants respectively. The endogenous ABA contents in the control plant were 236.3 ng g− 1 and in transgenic plants were 543.8 ng g− 1. The production of adventitious roots and trichomes were enhanced in the transgenic plants. Furthermore, transcript levels of the genes including IAA and ABA biosynthetic, and stress-responsive genes, were higher in the transgenic plants than in the control plants under drought conditions. Water use efficiency and a reduced water loss rate were enhanced in the transgenic strawberry plants. Additionally, peroxidase and catalase activities were significantly higher in the transgenic plants than in the control plants. The experiment results revealed a novel function for rty related to ABA and drought responses.ConclusionsThe rty gene improved hormone-mediated drought tolerance in transgenic strawberry. The heterologous expression of rty in strawberry improved drought tolerance by promoting auxin and ABA accumulation. These phytohormones together brought about various physiological changes that improved drought tolerance via increased root production, trichome density, and stomatal closure. Our results suggested that a transgenic approach can be used to overcome the inherent trade-off between plant growth and drought tolerance by enhancing water use efficiency and reducing water loss rate under water shortage conditions.

Aeration Volume and Inoculum Density Using in Bioreactor to Optimized Biomass Production and Secondary Metabolites in Gynura procumbens (Lour.) Merr. Adventitious Roots Culture

Phenolic compounds and flavonoids are secondary metabolite compositions of the Gynura procumbens plant. Limited amounts of these secondary metabolites in nature limit their potential as raw material for pharmaceutical drugs. Hence, the optimization of adventitious root culture in vitro should be used as an alternative to producing these compounds. Under optimal culture conditions, the target secondary metabolites can be significantly increased. In this work, we determined the optimum aeration volume and inoculum density on growth and secondary metabolite production of Gynura procumbens adventitious roots in a laboratory-scale bioreactor. The adventitious roots were cultured in a 2 L liquid MS in a 3 L capacity Balloon-Type Bubble Bioreactor (BTBB). The 3 g/L adventitious roots were cultured in 4 variations of aeration volume treatment. The best aeration treatment is 0.15 vvm were used in 4 variations of the inoculum density treatment. The highest biomass (75.38 ± 0.95 g/L), total phenolic contents production (27.98 mg/DW), and flavonoid production rates (256.24 mg/DW) from adventitious roots culture in the BTBB has produced from a treatment combination aeration volume of 0.15 vvm and inoculum density 3 g/L. Accumulation of malondialdehyde and proline in roots in that treatment was lower than other treatments. The four flavonoid compounds that known used as drugs pharmaceutical compound as myricetin, catechin, kaempferol, and quercetin was successfully determined under that treatment. These optimal conditions of aeration volume and inoculum density could be used to mass-produce the desired compounds from Gynura procumbens adventitious root on a pilot scale for industries.

Salt Tolerance in the Halophyte Suaeda maritima L. Dum.\u2014the Effect of Oxygen Supply and Culture Medium on Growth

Suaeda maritima is an annual species that grows in salt marshes and tolerates not only salt but also flooding, although plants are smaller at lower than at higher elevations of salt marshes. We investigated whether adventitious roots play a role in tolerance to flooding and how flooding affects ion accumulation in the shoots, a determinant of growth in this species. We examined the response of plants grown in Stout and Arnon culture solution to different periods of flooding at different salinities and verified our results with plants grown in other culture solutions (Hoagland and Yoshida). We measured growth, photosynthesis and estimated stomatal frequency as well as the accumulation of Na+, Ca2+, Mg2+ and K+: plants grew and photosynthesised optimally in 200-mM Na+ (in Stout and Arnon solution), but the optimal concentration for growth increased to 450 mM when in Yoshida solution. Flooding always decreased growth, but had little effect on Na+ concentrations. Although plants produced adventitious roots, their mass decreased rather than increased with flooding. The decrease in production of adventitious roots under flooded conditions suggested that they were not important in the tolerance of this species to submergence—an unusual response compared with the general response of flooding-tolerant plants.

Optimization of culture conditions for in vitro adventitious roots and selected flavonoids production in Boesenbergia rotunda liquid suspension culture

Boesenbergia rotunda (L.) Mansf. is one of the unique monocotyledonous perennial plant species belonging to the ginger (Zingiberaceae) family. Locally known as ‘Temu Kunci’ in Malaysia and Indonesia, this medicinal plant has been widely used in Asian dishes, particularly as a condiment or as traditional natural medicines. The important medicinal properties of B. rotunda majorly derived from flavonoids which are highly sought as pharmaceuticals. In this study, culture conditions for the growth of adventitious roots in liquid suspension cultures were optimized. The highest adventitious root production was achieved when cultured with initial inoculum density of 1.5 g and pH value at 5.8 after five weeks of culture. HPLC analysis discovered that production of valuable flavonoid compounds (pinostrobin, cardamonin and panduratin A) was significantly higher when the adventitious roots were cultured with initial inoculum density of 1.5 g whereas the initial pH medium did not significantly affect flavonoid production.

Vertical Production of ‘Konstancin’ Rose Cuttings in the Growth Chamber Under Led Light

Abstract The impact of light quality generated by light-emitting diodes (LEDs) on the adventitious root formation and cuttings’ quality of rose hip ‘Konstancin’ under controlled conditions in multilevel growth chamber without access to natural light and in the greenhouse was evaluated. In the growth chamber, the lighting was provided by a combination of red and blue LED arrays and white LED tubes, while in the greenhouse, red and blue LED lights were used as a supplement to natural light. The number of rooted cuttings under both growth conditions was not affected by the light conditions generated by LEDs. However, light quality showed significant effects on the biomass production and development of adventitious roots, with the most stimulating red light generated by LEDs. In the growth chamber, the root biomass of the cuttings illuminated with white LEDs supplemented with red LEDs was on average 2.2 times higher than of the cuttings illuminated with white LEDs only. A similar reaction was noted under greenhouse conditions. Supplementation of natural light with red LEDs resulted in 1.7 times increase of the fresh biomass of roots. Both in the growth chamber and in the greenhouse, illumination with red LEDs promoted axillary bud outgrowth. LED lamps can be used in the production of high-quality rose cuttings, both in greenhouses as a complement to natural light and in multilevel rooms as a sole-source lighting for plants.

Biomass and Flavonoid Production of Gynura procumbens Adventitious Roots Influenced by MS Salt Strength and Nitrogen Source in a Balloon-type Bubble Bioreactor

Biomass and Flavonoid Production of Gynura procumbens Adventitious Roots Influenced by MS Salt Strength and Nitrogen Source in a Balloon-type Bubble Bioreactor

Higher rates of liana regeneration after canopy fall drives species abundance patterns in central Amazonia

Abstract In tropical rainforest, most vascular plants have some capacity to resprout, and lianas are often effective resprouters after canopy fall. However, the diversity of resprouting responses of liana species and the consequence for plant persistence are poorly understood. We hypothesized that variation in regeneration among liana species causes differences in liana species abundance in tropical rainforest through differential resprouting capacity, such that liana species with higher densities produce more resprouts after canopy falls. We applied a manipulative field experiment investigating the effect of different levels of disturbance on the production of resprouts and adventitious roots in 10 liana species of the tribe Bignonieae (Bignoniaceae) with contrasting abundances in central Amazonia. We selected 15 individuals of each species and assigned the lianas to three distinct conditions: (a) total canopy fall with lianas severely damaged and detached from trees; (b) partial fall of lianas, without visible damage; and (c) intact lianas (control). We tested whether liana species regeneration patterns were related to species density. Liana species density was calculated using previous research on liana species distribution in 30 1‐ha plots systematically distributed in a 6 × 6 km2 grid at the Ducke Reserve. The number of aerial resprouts produced by lianas under the total canopy fall treatment was twice that of plants under lower levels of disturbance, while the production of adventitious roots did not differ among treatments. Liana species showed different intensities of resprouting, and species with higher average densities on the forest landscape had more resprouts after the total canopy fall treatment. Synthesis. Our results shed new light on the factors that influence liana species abundance, highlighting the role of resprouting after canopy fall and its variation among liana species. Resprouting mitigates the negative effects of canopy damage, suggesting that the impact of increased tree fall disturbances over time, which has been attributed to Amazonian forests in the literature, may increase already abundant liana species with effective resprouting capacity. We identify liana species that are more resilient to disturbance and may alter forest dynamics during climatic change.

Oplopanax elatus adventitious root production through fed-batch culture and their anti-bacterial effects

Fed-batch culture (FBC) is extensively used in microbial culture to achieve a high yield of the desired products. However, the FBC application is less in plant cells or organs because of relatively complex chemical components in the culture medium. To develop the FBC of adventitious roots (ARs) of Oplopanax elatus, the present study designed two FBC systems, where the initial culture media were controlled as 3 L of half- (FBC1) and full-strength (FBC2) of Murashige and Skoog medium, and the culture efficiency was compared with the batch culture (BC). The result showed that AR biomass and bioactive compound accumulation were favorable in both FBC systems compared with those in the BC system. Between FBC1 and FBC2, a significant difference was exerted, with the former showing a good culture efficiency, and 5381.6 mg l−1 of total polysaccharides and 950.8 mg l−1 of total flavonoids were produced in FBC1. In addition, the anti-bacterial property of O. elatus ARs was evaluated for their further using in the production of relative products. The extract from FBC1-cultured ARs (OAE) inhibited growth of bacteria including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis, and a higher anti-bacterial effect was found on E. coli. Consequently, the effects of OAE on cell permeability and oxidative respiratory metabolism of E. coli were investigated. The levels of alkaline phosphatase activity, nucleotide or protein leakage, and electrical conductivity in the bacterial substrate were increased by the OAE treatment, illustrating that OAE changed the permeability of cell membranes or walls of E. coli. Simultaneously, OAE inhibited the respiratory of E. coli and a low superposition rate (30.5%) was found in the combination group of OAE with sodium phosphate. Furthermore, the activity of the key enzyme (glucose-6-phosphate dehydrogenase) in the hexose monophosphate (HMP) pathway was obviously decreased by the OAE treatment, confirming that OAE exerts its anti-bacterial effect on E. coli by regulating the HMP pathway. Fed-batch culture improves culture efficiency of Oplopanax elatus adventitious roots. Large amounts of polysaccharides and flavonoids were produced in fed-batch culture. Adventitious roots possessed higher anti-bacterial effect against Escherichia coli. Cell permeability of Escherichia coli were changed by treatments of adventitious root extracts. Extracts inhibited respiratory of Escherichia coli by affecting hexose monophophate pathway.