Physiological and biochemical regulation of Valeriana jatamansi Jones under water stress.

Understanding the physiological and biochemical regulations in a medicinal plant under stress environments is essential. Here, the effect of water stress such as flooding and water deficit [80% (control), 60%, 40%, 20% field capacity (FC)] conditions on Valeriana jatamansi was studied. Both types of water stresses retarded the plant growth and biomass. Photosynthetic pigments were reduced with maximum reduction under flood stress. Chlorophyll fluorescence study revealed distinct attributes under applied stresses. Better performance index (PI) of flood-grown plants (than 20% and 40% FC) and higher relative fluorescence decrease ratio (Rfd) in 40% FC and flood-grown plants than that of control plants, indicated the adaptation ability of plants under water deficit (40% FC) and flood stress. Reduction in net photosynthetic rate was lesser in flood stress (40.92%) compared to drought stress (73.92% at 20% FC). Accumulation of starch was also decreased (61.1% at 20% FC) under drought stress, while it was increased (24.59%) in flood stress. The effect of water stress was also evident with modulation in H2O2 content and membrane damage. Differential modulation of biosynthesis of secondary metabolites (valtrate, acevaltrate and hydroxyl valerenic acid) and expression of iridoid biosynthetic genes under water stress was also revealed. The present study demonstrated the distinct effect of drought and flood stress on V. jatamansi plants, and drought [20% FC] caused severe loss and more damage than flood stress. Therefore, severe drought should be avoided during cultivation of V. jatamansi and regulated water stress-applications have potential for modulation of biosynthesis of specific secondary metabolites.

Endomicrobiome of in vitro and natural plants deciphering the endophytes-associated secondary metabolite biosynthesis in Picrorhiza kurrooa, a Himalayan medicinal herb.

IMPORTANCE: Picrorhiza kurrooa is a major source of picrosides, potent hepatoprotective molecules. Due to the ever-increasing demands, overexploitation has caused an extensive decline in its population in the wild and placed it in the endangered plants' category. At present plant in-vitro systems are widely used for the sustainable generation of P. kurrooa plants, and also for the conservation of other commercially important, rare, endangered, and threatened plant species. Furthermore, the in-vitro-generated plants had reduced content of therapeutic secondary metabolites compared to their wild counterparts, and the reason behind, not well-explored. Here, we revealed the loss of plant-associated endophytic communities during in-vitro propagation of P. kurrooa plants which also correlated to in-planta secondary metabolite biosynthesis. Therefore, this study emphasized to consider the essential role of plant-associated endophytic communities in in-vitro practices which may be the possible reason for reduced secondary metabolites in in-vitro plants.

Role of Nutraceuticals and Physical Activity in Parkinson's Disease Risk and Lifestyle Management.

BACKGROUND: Parkinson's disease is a complicated, gradually progressive neurological illness characterized by locomotor and non-motor symptomatology that impedes daily activities. Despite significant advances in symptomatic therapies with various extents of negative effects, there are currently no disease-modifying medicinal alternatives. Symptoms worsen, creating an additional strain that reduces living quality and creates the perception that prescription drugs are no longer productive. OBJECTIVE: Adopting healthy lifestyle habits can help patients feel more empowered, promote wellness, relieve symptoms, and potentially slow neurodegeneration. Nutrition, intellectual stimulation, physical exercise, and stress reduction are all examples of lifestyle habits that improve cognitive health and life satisfaction. We discuss how changes in lifestyle, nutrition, yoga, exercise, and acupuncture can help with managing the disease's symptoms. METHODS: We searched Google Scholar for various research papers and review articles from publishers, such as Bentham Science, Elsevier, Taylor and Francis, Springer Nature, and others for gathering the data for the study. RESULTS: Pesticide exposure, environmental hazards, dietary choices, stress, and anxiety all have an indirect or immediate influence on the commencement of Parkinson's disease. Naturopathic remedies, such as nutraceuticals, yoga, exercise, and acupuncture, have been shown to help with Parkinson's disease management. CONCLUSION: Various preclinical and clinical studies have shown that the various factors mentioned are beneficial in the management of the disease, but more research is needed to validate the extent to which such factors are beneficial.

Corrigendum: Calliterpenone, a natural plant growth promoter from a medicinal plant Callicarpa macrophylla, sustainably enhances the yield and productivity of crops.

[This corrects the article DOI: 10.3389/fpls.2022.960717.].

Calliterpenone, a natural plant growth promoter from a medicinal plant Callicarpa macrophylla, sustainably enhances the yield and productivity of crops.

The global population is rising at an alarming rate, which is threatening food and nutritional security. Although chemical fertilizers and pesticides are important for achieving food security, their excessive usage critically affects soil health and adds up residues in the food chain. There is an increasing interest in identifying eco-friendly farm inputs that can improve crop productivity through sustainable agricultural practices. One of the most common approaches to reducing chemical inputs in agriculture is the use of plant growth regulators (PGRs). Here, we demonstrate the benefits of a natural and novel plant growth enhancer "calliterpenone," isolated from Callicarpa macrophylla, a medicinal plant, for increasing crop productivity in six crops, viz., rice, wheat, potato, tomato, chickpea, and onion. Results revealed that the application of calliterpenone (foliar spraying or seed soaking) enhanced the yield of rice (28.89%), onion (20.63%), potato (37.17%), tomato (28.36%), and chickpea (26.08%) at 0.001 mM and of wheat (27.23%) at 0.01 mM concentrations in comparison to control. This enhancement in yield was reflected through improvements in its growth attributes, viz., spike length, tillers plant-1, seeds spike-1, plant height, and biomass. Furthermore, the exogenous application of calliterpenone could increase the endogenous level of indole-3-acetic acid (IAA) in all tested crops and decrease the content of abscisic acid (ABA) in a few. Trials conducted at farmers' fields showed an overall ~12% increase in rice yield (mean of 11 farmers' fields ranging from 3.48 to 19.63%) and ~10% increase in wheat yield (ranging from 3.91 to 17.51%). The 0.001 mM of calliterpenone was the best effective dose for most crops except wheat, where a concentration of 0.01 mM was found to be the most optimal. This study indicates that calliterpenone is a natural plant growth promoter that can be used in boosting the yields of multiple crops and would be an important input component of organic farming.

Arnebia euchroma, a Plant Species of Cold Desert in the Himalayas, Harbors Beneficial Cultivable Endophytes in Roots and Leaves.

The endophytic mutualism of plants with microorganisms often leads to several benefits to its host including plant health and survival under extreme environments. Arnebia euchroma is an endangered medicinal plant that grows naturally in extreme cold and arid environments in the Himalayas. The present study was conducted to decipher the cultivable endophytic diversity associated with the leaf and root tissues of A. euchroma. A total of 60 bacteria and 33 fungi including nine yeasts were isolated and characterized at the molecular level. Among these, Proteobacteria was the most abundant bacterial phylum with the abundance of Gammaproteobacteria (76.67%) and genus Pseudomonas. Ascomycota was the most abundant phylum (72.73%) dominated by class Eurotiales (42.42%) and genus Penicillium among isolated fungal endophytes. Leaf tissues showed a higher richness (S chao 1) of both bacterial and fungal communities as compared to root tissues. The abilities of endophytes to display plant growth promotion (PGP) through phosphorus (P) and potassium (K) solubilization and production of ACC deaminase (ACCD), indole acetic acid (IAA), and siderophores were also investigated under in vitro conditions. Of all the endophytes, 21.51% produced ACCD, 89.25% solubilized P, 43.01% solubilized K, 68.82% produced IAA, and 76.34% produced siderophores. Six bacteria and one fungal endophyte displayed all the five PGP traits. The study demonstrated that A. euchroma is a promising source of beneficial endophytes with multiple growth-promoting traits. These endophytes can be used for improving stress tolerance in plants under nutrient-deficient and cold/arid conditions.

Application of essential oils as a natural and alternate method for inhibiting and inducing the sprouting of potato tubers.

Use of harmful chemicals and expensive maintenance of cold-storage conditions for controlling sprouting are among the major problems in potato storage. Here, 20 essential oils (EOs) were tested for their sprouting-inhibiting and sprouting-inducing activities. Overall, treatments of lemon grass (LG) and clove (CL) oils could induce sprouting whereas palmarosa (PR) and ajwain (AZ) oils could inhibit sprouting of potato tubers at normal-room-temperature (25 ±â€¯2 °C) storage. Selected-EOs treatments affected sprouting by modulation of accumulation of reducing sugars, ethylene, and expression of genes involved in tuber-sprouting such as ARF, ARP, AIP and ERF. Surprisingly, 7-days AZ-treatments could inhibit sprouting for 30-days which was mediated via damaging apical meristem. However, LG- and CL-treated tubers could produce enhanced potato yield as well. Present work clearly demonstrates that selected-EOs can be used as a promising eco-friendly approach for inducing/inhibiting sprouting of potato tubers during potato storage and those enhancing sprouting can be used for enhancing productivity.

Enhanced expression of ginsenoside biosynthetic genes and in vitro ginsenoside production in elicited Panax sikkimensis (Ban) cell suspensions.

Dual metabolite, i.e., ginsenoside and anthocyanin, co-accumulating cell suspensions of Panax sikkimensis were subjected to elicitation with culture filtrates of Serratia marcescens (SD 21), Bacillus subtilis (FL11), Trichoderma atroviridae (TA), and T. harzianum (TH) at 1.25% and 2.5% v/v for 1- and 3-week duration. The fungal-derived elicitors (TA and TH) did not significantly affect biomass accumulation; however, bacterial elicitors (SD 21 and FL11), especially SD 21, led to comparable loss in biomass growth. In terms of ginsenoside content, differential responses were observed. A maximum of 3.2-fold increase (222.2 mg/L) in total ginsenoside content was observed with the use of 2.5% v/v TH culture filtrate for 1 week. Similar ginsenoside accumulation was observed with the use of 1-week treatment with 2.5% v/v SD 21 culture filtrate (189.3 mg/L) with a 10-fold increase in intracellular Rg2 biosynthesis (31 mg/L). Real-time PCR analysis of key ginsenoside biosynthesis genes, i.e., FPS, SQS, DDS, PPDS, and PPTS, revealed prominent upregulation of particularly PPTS expression (20-23-fold), accounting for the observed enhancement in protopanaxatriol ginsenosides. However, none of the elicitors led to successful enhancement in in vitro anthocyanin accumulation as compared to control values.