Metabolomic profiling of wild rooibos (Aspalathus linearis) ecotypes and their antioxidant-derived phytopharmaceutical potential.

INTRODUCTION: Aspalathus linearis (commonly known as rooibos) is endemic to the Cape Floristic Region of South Africa and is a popular herbal drink and skin phytotherapeutic ingredient, with health benefits derived primarily from its unique phenolic content. Several, seemingly habitat-specific ecotypes from the Cederberg (Western Cape) and Northern Cape have morphological, ecological, genetic and biochemical differences. OBJECTIVES AND METHODS: Despite the commercial popularity of the cultivated variety, the uncultivated ecotypes are largely understudied. To address gaps in knowledge about the biochemical constituency, ultra-performance liquid chromatography-mass spectrometry analysis of fifteen populations was performed, enabling high-throughput metabolomic fingerprinting of 50% (v/v) methanolic extracts. Antioxidant screening of selected populations was performed via three assays and antimicrobial activity on two microbial species was assessed. The metabolomic results were corroborated with total phenolic and flavonoid screening of the extracts. RESULTS AND DISCUSSION: Site-specific chemical lineages of rooibos ecotypes were confirmed via multivariate data analyses. Important features identified via PLS-DA disclosed higher relative abundances of certain tentative metabolites (e.g., rutin, aspalathin and apiin) present in the Dobbelaarskop, Blomfontein, Welbedacht and Eselbank sites, in comparison to other locations. Several unknown novel metabolites (e.g., m/z 155.0369, 231.0513, 443.1197, 695.2883) are responsible for metabolomic separation of the populations, four of which showed higher amounts of key metabolites and were thus selected for bioactivity analysis. The Welbedacht and Eselbank site 2 populations consistently displayed higher antioxidant activities, with 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities of 679.894 ± 3.427 µmol Trolox/g dry matter and 635.066 ± 5.140 µmol Trolox/g dry matter, respectively, in correlation with a high number of phenolic and flavonoid compounds. The contribution of the individual metabolites to the pharmacological effectiveness of rooibos remains unknown and as such, further structural elucidation and phytopharmacological testing is thus urgently needed.

Comprehensive metabolite and biological profile of "Sulmona Red Garlic" ecotype's aerial bulbils.

"Sulmona Red Garlic" is a well-known Italian traditional product. Bulbs, used for culinary purposes, have been largely investigated for their medicinal properties whereas aerial bulbils are usually removed as waste material. Here, for the first time, chemical composition and biological properties of the hydroalcoholic extract from aerial bulbils were investigated. Complementary information on metabolite composition were obtained using both NMR based untargeted and HPLC-DAD targeted methodologies. The NMR analysis revealed the presence of sugars, organic acids, amino acids, organosulphur compounds (methiin, alliin, allicin and cycloalliin), and other secondary metabolites. In particular, methiin and alliin were identified for the first time in the NMR spectra of aerial bulbil garlic extracts. Polyphenol content was determined by HPLC-DAD analysis: catechin, chlorogenic acid, and gallic acid turned out to be the most abundant phenolics. Hydroalcoholic extract blocked cell proliferation of colon cancer cell line HCT116 with an IC50 of 352.07 µg/mL, while it was non-toxic to myoblast cell line C2C12. In addition, it caused seedling germination reduction of two edible and herbaceous dicotyledon species, namely Cichorium intybus and C. endivia. Moreover, the same extract reduced the gene expression of TNF-α (tumor necrosis factor), HIF1-α (hypoxia-inducible factor), VEGFA (vascular endothelial growth factor), and transient receptor potential (TRP) M8 (TRPM8) indicating the ability to contrast cancer development through the angiogenic pathway. Final, in silico experiments were also carried out supporting the biological effects of organosulphur compounds, particularly alliin, which may directly interact with TRPM8. The results here reported suggest the potential use of garlic aerial bulbils often considered a waste product as a source in phytotherapeutic remedies.

Quantification of fatty acids in seed oil and important bioactive compounds in Iranian Rosa canina L. ecotypes for potential cosmetic and medicinal uses.

Rosa canina L. (Rosaceae), commonly known as the rose hip, is originated from Europe, Africa, and Asia with a long history in medicinal applications. This study aimed to analyze the morphological traits, fatty acids profile, and content of phenolic compounds, anthocyanins, vitamin C, total carotenoid, total phenol, total flavonoid, and antioxidant activity of the fruits of eleven Iranian R. canina ecotypes (RCEs). The highest coefficient of variation was obtained in 1000 seed weight (46.57%). The seed oil varied from 8.08 ± 0.17% to 16.91 ± 0.35%. Linoleic (35.41 ± 0.78% to 49.59 ± 0.96%) and eicosanoic (17.67 ± 0.06% to 25.36 ± 0.54%) acids were the predominant fatty acids in the studied samples. The anthocyanin content in the fruits was ranged from 0.98 ± 0.03 to 4.41 ± 0.04 mg cyanidin 3-glucoside/100 g of dry weight (mg C3G/100 g DW). The high content of vitamin C (103.51 ± 1.24-419.70 ± 3.12 mg/100 g DW), total carotenoid (111.22 ± 0.78-206.98 ± 1.25 mg ß-carotene equivalents per g of dry weight (mg ß-CARE/g DW)), total phenol (52.87 ± 0.82-104.52 ± 0.23 mg GAE/g DW), and total flavonoid (14.20 ± 0.12-25.18 ± 0.47 mg RE/g DW) were observed in the studied samples. Catechin (20.42 ± 0.47-19.22 ± 0.13 µg/g DW) was the major phenolic compound. The high antioxidant activity in the fruits of the plant was recorded in the studied RCEs (IC50 = 12.54 ± 0.18-26.33 ± 0.13 µg/ml). A significant correlation between some phytochemical compounds (dependent variable) and morphological features (independent variable) was found. Based on our findings, the fruit of the studied ecotypes can be used for future breeding programs and drug development.

Effect of Ecotype and Starch Isolation Methods on the Physicochemical, Functional, and Structural Properties of Ethiopian Potato (Plectranthus edulis) Starch.

The Ethiopian potato (Plectranthus edulis) is an annual tuber crop indigenous to Ethiopia. The crop is underutilized and not much studied despite its high yield of starch, which has a good potential to contribute to the effort in meeting the quickly growing demand for starch. In this study, the effects of the ecotype and isolation methods on the physicochemical, functional, structural, and crystalline properties of starches were evaluated. Starches were isolated from two Ethiopian potato ecotypes (Loffo and Chanqua) using distilled water (DW), 0.01% sodium metabisulphite (SMS), and 1M sodium chloride (NaCl) in the isolation media. The results showed that the lowest starch yield was obtained from Chanqua using DW (97.4%), while the maximum was from Loffo using SMS (99.3%). The L* (lightness) and whiteness values of the starches obtained from Loffo were higher than those of Chanqua starches, with NaCl and SMS extractants yielding the highest values. The bulk density, water activity (aw), pH, proximate composition (moisture content, protein, ash, fat, crude fiber, and carbohydrate contents), and techno-functional properties were established. The majority of these parameters varied depending on both the isolation method and the ecotype. The crystallinity pattern of all starches showed B-type diffraction, with differences in diffraction peak intensities between all starches. FTIR tests showed structural changes as a function of the ecotype and isolation procedure used. The Loffo ecotype exhibited considerably better results, and the SMS isolation method was found to be the most effective way to acquire the highest starch quality in most of the characteristics evaluated.

Photoprotective and antigenotoxic properties of Cutibacterium acnes ecotypes native to terrestrial subsurface habitats.

Actinobacteria are known to produce a variety of secondary metabolites with skin-protective properties. This study aimed to investigate the photoprotective and antigenotoxic properties against UVB of extracts obtained from Cutibacterium acnes strains. Bacterial growth was measured spectrophotometrically and the constant maximum growth rate (µ) value to each strain, were calculated. In vitro photoprotection efficacy was evaluated using in vitro indices such as sun protection factor (SPFespectrophotometric) and critical wavelength (λc). UVB-antigenotoxicity was also evaluated using the SOS Chromotest. Correlation analysis was used to examine the relationship between SPFespectrophotometric and extract concentration and the %GI estimates. Among the studied strains, one showed low (6.0 ≤ SPFespectrophotometric ≤ 14.9) and eight showed media (15.0 ≤ SPFespectrophotometric ≤ 29.9) UVB photoprotection efficacy. All of them resulted in broad-spectrum (UVA-UVB) photoprotection (λc > 370 nm). In total, two C. acnes ecotypes with different growth rates were evidenced, but the protective metabolites in the extracts were produced without the influence of growth rate. Photoprotective efficacy depended on the extract concentration and was correlated with antigenotoxicity. We demonstrated that C. acnes extracts can be used as sunscreen ingredients that reduce UVB-induced genotoxicity.

Larger presence of ectomycorrhizae detected from pygmy pine ecotype in the fire-frequent pine barrens ecosystem.

Pine barrens ecosystem has acidic, sandy, and nutrient-poor soil and is prone to drought and fire. In the New Jersey Pine Barrens, the predominant pitch pine (Pinus rigida) consists of two ecotypes: the regular pitch pines with heights of 4.6-12 m, and the pygmy pines of low stature (1.2-1.8 m) in the New Jersey Pine Plains. Previous ecological studies suggested that the dwarf pines in the Pine Plains that are embedded within the Pine Barrens were an evolutionary adaptation to frequent fire. Pines are obligate ectomycorrhizal (EcM) mutualists, and their root mycobiota may contribute to stress protection and plant health. However, information on the mycobiota associated with plants in the pine barrens ecosystem is lacking. To have a holistic understanding of the evolution and adaptation in this stressed environment, we used both culture-independent metabarcoding and culture-based method to characterize the mycobiota from soil and root of the two ecotypes and to identify core mycobiota. We found that Agaricomycetes, Leotiomycetes, and Mucoromycotina are predominant fungi in the New Jersey Pine Barrens ecosystem, which is rich in root mutualistic fungi. We observed that the pygmy pine roots had significantly higher density of EcM tips than the regular pine roots. This was corroborated by our metabarcoding analysis, which showed that the pygmy pine trees had higher ratio of ectomycorrhiza-forming fungi than the regular-statured pines. We hypothesize that symbiotrophic EcM fungi associated with pygmy pines are capable of mitigating high fire stress in the Pine Plains.

Integrated Multiomics and Synergistic Functional Network Revealed the Mechanism in the Tolerance of Different Ecotypes of Salvia miltiorrhiza Bge. to Doxycycline Pollution.

Tetracycline pollution in soil irreversibly damages the biosafety of plants by inhibiting the mitochondrial function. Some traditional Chinese medicine (TCM) plants, such as Salvia miltiorrhiza Bunge, have a strong tolerance to mitochondrial damage. We comprehensively compared the doxycycline (DOX) tolerances of two ecotypes of S. miltiorrhiza in the Sichuan and Shandong provinces and found that the Sichuan ecotype had a lower yield reduction, more stable accumulation of medicinal ingredients, higher mitochondrial integrity, and a more robust antioxidant system. The synergetic response networks under DOX pollution of both ecotypes were constructed using RNA sequencing and ultrahigh-performance liquid chromatography-tandem mass spectrometry. The differentiation of the downstream pathways of aromatic amino acids (AAAs) produced variations in the DOX tolerance of S. miltiorrhiza in different regions. The Sichuan ecotype maintained redox homeostasis and xylem development by activating salvianolic acid and indole biosynthesis, while the Shandong ecotype balanced chemical and mechanical defenses by regulating the flavonoid biosynthesis. Rosmarinic acid, a downstream AAA molecule, maintains the mitochondrial homeostasis of plant seedlings under DOX pollution by targeting the ABCG28 transporter. We also highlight the significance of downstream AAA small molecules in guiding the development of bio-based environmental pollution remediation agents.

Multivariate analysis of seed chemical diversity among wild fenugreek (Trigonella monantha C. A. Mey.) ecotypes.

BACKGROUND: Wild fenugreek (Trigonella monantha), a multi-purpose annual plant, has traditionally been used as a food, forage, and medicinal plant. However, the knowledge of the diversity of its chemical characteristics is limited. In this study, 40 wild fenugreek ecotypes collected from their natural habitats in Iran and grown together in field conditions, were analyzed for their seed chemical properties. RESULTS: The ecotypes were cultivated in a randomized complete block design (RCBD) with three replications. The results of ANOVA revealed a significant difference among the ecotypes for all measured characters (P < 0.01). The results showed a high level of diversity among the ecotypes based on the measured characters, including antioxidant activity (48.19 to 86.85%), phenol (0.82 to 1.51 mg gallic acid per g dry weight), flavonoid (1.07 to 3.11 mg quercetin per g dry weight), trigonelline (0.02 to 0.08 mmol/l), 4-hydroxyisoleucine (0.197 to 0.906 mg/g), sucrose (0.13 to 3.77 mM), glucose (1.07 to 12.1 mM), and fructose (13.3 to 45.5 mM). The cluster analysis divided the ecotypes into four groups and the PCA analysis showed that the three first components explained 73% of the total variance among the ecotypes. Also, heat map correlation revealed that many positive and negative correlations were observed among the measured characters. The results did not show a relationship between the amounts of compounds and the place of sample collection. CONCLUSIONS: The present study suggests considerable diversity in the seed chemical compositions of the wild fenugreek ecotypes. Therefore, many ecotypes could be useful for medicinal purposes, as well as for human nutrition.

Identification of a secondary Q-marker in high-quality ecotypes of Carthamus tinctorius L. and exploration of the target preference.

Safflower (Carthamus tinctorius) has the efficacy for promoting blood circulation and preventing cardiovascular and Alzheimer's diseases and is thus a valuable medicinal and functional food plant. However, how to evaluate high-quality safflower is still a problem. To differentiate intraspecies ecotypes and illustrate the mechanisms of differential metabolites of C. tinctorius from different regions, this study combined the widely targeted metabolome, weighted network pharmacology, and molecular docking to filter bioactive compounds and predict the target preference. The results indicated that kaempferol is suitable as a secondary Q-marker to differentiate intraspecies ecotypes. In secondary metabolites, the average content of kaempferol and its derivates in C. tinctorius from Sichuan is three times that of other areas, which have the potential for the targeted medicine of CA2 and TNF. In volatile metabolites, isoaromadendrene epoxide has the potential as a specifically targeted medicine of RXRA. The change of the target preference could be the reason for the difference in drug efficacy among different varieties of C. tinctorius. It is reasonable that Sichuan was recognized as a high-quality ecotype producing region of C. tinctorius in China, which promotes blood circulation and removes blood stasis. This study provides an innovative method to differentiate intraspecies ecotypes and explore their target preference.

Methyl Jasmonate Induces Genes Involved in Linalool Accumulation and Increases the Content of Phenolics in Two Iranian Coriander (Coriandrum sativum L.) Ecotypes.

The medicinal herb coriander (Coriandrum sativum L.), with a high linalool (LIN) content, is widely recognized for its therapeutic benefits. As a novel report, the goals of this study were to determine how methyl jasmonate (MeJA) affects total phenolic content (TPC), LIN content, flavonoid content (TFC), and changes in gene expression involved in the linalool biosynthesis pathway (CsγTRPS and CsLINS). Our findings showed that, in comparison to the control samples, MeJA treatment substantially enhanced the TPC, LIN, and TFC content in both ecotypes. Additionally, for both Iranian coriander ecotypes, treatment-induced increases in CsγTRPS and CsLINS expression were connected to LIN accumulation in all treatments. A 24 h treatment with 150 µM MeJA substantially increased the LIN content in the Mashhad and Zanjan ecotypes, which was between 1.48 and 1.69 times greater than that in untreated plants, according to gas chromatography-mass spectrometry (GC-MS) analysis. Our findings demonstrated that MeJA significantly affects the accumulation of LIN, TPC, and TFC in Iranian C. sativum treated with MeJA, which is likely the consequence of gene activation from the monoterpene biosynthesis pathway. Our discoveries have improved the understanding of the molecular mechanisms behind LIN synthesis in coriander plants.

Genetic basis of maturity time is independent from that of flowering time and contributes to ecotype differentiation in common buckwheat (Fagopyrum esculentum Moench).

BACKGROUND: Common buckwheat is considered a quantitative short-day plant and is classified into the autumn (highly photoperiod sensitive), summer (weakly photoperiod sensitive), and intermediate ecotype. Understanding ecotype differentiation is essential for adaptive expansion and maximizing yield. The genetic analysis for ecotype has focused on photoperiod-dependent flowering time, whereas post-flowering traits such as seed set and maturity time might also regulate ecotype differentiation. RESULTS: A field experiment revealed that ecotype differentiation is mainly defined by the timing of seed set and maturation, whereas flowering time is less relevant. Thus, we focused on maturity time as a trait that defines the ecotype. To detect QTLs for maturity time, we developed two F2 populations derived from early × late-maturing accessions and intermediate × late-maturing accessions. Using genotyping by random amplicon sequencing-direct analysis, we generated a high-density linkage map. QTL analysis detected two major QTLs for maturity time, one in each F2 population. We also detected QTLs for flowering time at loci different from maturity time QTLs, which suggests that different genetic mechanisms regulate flowering and maturity. Association analysis showed that both QTLs for maturity time were significantly associated with variations in the trait across years. CONCLUSIONS: Maturity time appeared to be more suitable for explaining ecotype differentiation than flowering time, and different genetic mechanisms would regulate the timing of flowering and maturation. The QTLs and QTL-linked markers for maturity time detected here may be useful to extend the cultivation area and to fine-tune the growth period to maximize yield in buckwheat.

Ecotype Division and Chemical Diversity of Cynomorium songaricum from Different Geographical Regions.

Cynomorium songaricum is an important endangered plant with significant medicinal and edible values. However, the lack of resources and quality variation have limited the comprehensive developments and sustainable utilization of C. songaricum. Here, we evaluated the chemical and genetic traits of C. songaricum from the highly suitable habitat regions simulated with species distribution models. The PCA and NJ tree analyses displayed intraspecific variation in C. songaricum, which could be divided into two ecotypes: ecotype I and ecotype II. Furthermore, the LC-MS/MS-based metabolomic was used to identify and analyze the metabolites of two ecotypes. The results indicated that a total of 589 compounds were detected, 236 of which were significantly different between the two ecotypes. Specifically, the relative content and the kind of flavonoids were more abundant in ecotype I, which were closely associated with the medicinal activities. In contrast, amino acids and organic acids were more enriched in ecotype II, which may provide better nutritional quality and unique flavor. In summary, our findings demonstrate the ecotype division and chemical diversity of C. songaricum in China from different geographical regions and provide a reference for the development of germplasm and directed plant breeding of endangered medicinal plants.

Comparison of buckwheat genomes reveals the genetic basis of metabolomic divergence and ecotype differentiation.

Golden buckwheat (Fagopyrum dibotrys or Fagopyrum cymosum) and Tartary buckwheat (Fagopyrum tataricum) belong to the Polygonaceae and the Fagopyrum genus is rich in flavonoids. Golden buckwheat is a wild relative of Tartary buckwheat, yet golden buckwheat is a traditional Chinese herbal medicine and Tartary buckwheat is a food crop. The genetic basis of adaptive divergence between these two buckwheats is poorly understood. Here, we assembled a high-quality chromosome-level genome of golden buckwheat and found a one-to-one syntenic relationship with the chromosomes of Tartary buckwheat. Two large inversions were identified that differentiate golden buckwheat and Tartary buckwheat. Metabolomic and genetic comparisons of golden buckwheat and Tartary buckwheat indicate an amplified copy number of FdCHI, FdF3H, FdDFR, and FdLAR gene families in golden buckwheat, and a parallel increase in medicinal flavonoid content. Resequencing of 34 wild golden buckwheat accessions across the two morphologically distinct ecotypes identified candidate genes, including FdMYB44 and FdCRF4, putatively involved in flavonoid accumulation and differentiation of plant architecture, respectively. Our comparative genomic study provides abundant genomic resources of genomic divergent variation to improve buckwheat with excellent nutritional and medicinal value.

[Resistance of different ecotypes of Gastrodia elata to tuber rot].

Tuber rot has become a serious problem in the large-scale cultivation of Gastrodia elata. In this study, we compared the resistance of different ecotypes of G. elata to tuber rot by field experiments on the basis of the investigation of G. elata diseases. The histological observation and transcriptome analysis were conducted to reveal the resistance differences and the underlying mechanisms among different ecotypes. In the field, G. elata f. glauca had the highest incidence of tuber rot, followed by G. elata f. viridis, and G. elata f. elata and G. elata f. glauca×G. elata f. elata showed the lowest incidence. Tuber rot showcased obvious plant source specificity and mainly occurred in the buds and bottom of G. elata plants. After infection, the pathogen spread hyphae in host cortex cells, which can change the endophytic fungal community structure in the cortex and parenchyma of G. elata. G. elata f. glauca had thinner lytic layer and more sugar lumps in the parenchyma than G. elata f. elata. The transcription of genes involved in immune defense, enzyme synthesis, polysaccharide synthesis, carbohydrate transport and metabolism, hydroxylase activity, and aromatic compound synthesis had significant differences between G. elata f. glauca and G. elata f. elata. These findings suggested that the differences in resis-tance to tuber rot among different ecotypes of G. elata may be related to the varied gene expression patterns and secondary metabolites. This study provides basic data for the prevention and control of tuber rot and the improvement of planting technology for G. elata.

Change in Secondary Metabolites and Expression Pattern of Key Rosmarinic Acid Related Genes in Iranian Lemon Balm (Melissa officinalis L.) Ecotypes Using Methyl Jasmonate Treatments.

The medicinal herb, lemon balm (Melissa officinalis L.), which is high in rosmarinic acid (RA), has well-known therapeutic value. The goals of this study were to investigate the effects of methyl jasmonate (MeJA) on RA content, total phenolic content (TPC), and total flavonoid content (TFC), as well as changes in expression of their biosynthesis-related key genes (MoPAL, Mo4CL, and MoRAS) in Iranian lemon balm ecotypes, as first reported. Our results revealed that MeJA doses significantly increase the RA content, TPC, and TFC in both ecotypes compared with the control samples. Additionally, the higher expression levels of MoPAL, Mo4CL, and MoRAS following treatment were linked to RA accumulation in all treatments for both Iranian lemon balm ecotypes. After 24 h of exposure to 150 µM MeJA concentration, HPLC analysis showed that MeJA significantly increased RA content in Esfahan and Ilam ecotypes, which was about 4.18- and 7.43-fold higher than untreated plants. Our findings suggested that MeJA has a considerable influence on RA, TPC, and TFC accumulation in MeJA-treated Iranian M. officinalis, which might be the result of gene activation from the phenylpropanoid pathway. As a result of our findings, we now have a better understanding of the molecular processes behind RA production in lemon balm plants.

Genetic diversity of Norway spruce ecotypes assessed by GBS-derived SNPs.

We investigated the genetic structure of three phenotypically distinct ecotypic groups of Norway spruce (Picea abies) belonging to three elevational classes; namely, low- (acuminata), medium- (europaea), and high-elevation (obovata) form, each represented by 150 trees. After rigorous filtering, we used 1916 Genotyping-by-Sequencing generated SNPs for analysis. Outputs from three multivariate analysis methods (Bayesian clustering algorithm implemented in STRUCTURE, Principal Component Analysis, and the Discriminant Analysis of Principal Components) indicated the presence of a distinct genetic cluster representing the high-elevation ecotypic group. Our findings bring a vital message to forestry practice affirming that artificial transfer of forest reproductive material, especially for stands under harsh climate conditions, should be considered with caution.

Plant growth promoters mediated quality and yield attributes of milk thistle (Silybum marianum L.) ecotypes under salinity stress.

Silybum marianum (L.) Gaertn (Astraceae) is a well-reputed medicinal plant mostly utilized for silymarin (Sily) content and oil production, however, the information about Sily contents in achene part is still fragmented under different climatic conditions. In this study four milk thistle ecotypes from Faisalabad (FSD), Gujranwala (GUJ), Quetta (QTA), and Kallar kahar (KK) having an altered achene color were analyzed under salt stress. Application of plant growth promoters (PGPs) is one of the solution for ameliorating the effect of salinity and increasing the quantity and quality traits of milk thistle, so ascorbic acid (AsA), thiourea (TU), and moringa leaf extract (MLE) were soil supplied after developing salinity stress (120 mM with irrigation) at germination stage. Predetermined levels were selected for PGPs such as AsA (500 µM), MLE (3%), and TU (250 µM). Results revealed that all yield related attributes were significantly decreased, while secondary metabolites, pericarp epidermis, pericarp parenchyma, and pericarp seed integument increased under salinity stress. Data suggested that PGPs treatment was helpful to alleviate the deleterious effects of salinity stress and enhance the milk thistle quality and quantity parameters. The ecotypic variations with altered achene color patterns represent an advantage for QTA ecotypes for higher Sily extraction under salt stressed conditions.

Natural variation in wild tomato trichomes; selecting metabolites that contribute to insect resistance using a random forest approach.

BACKGROUND: Plant-produced specialised metabolites are a powerful part of a plant's first line of defence against herbivorous insects, bacteria and fungi. Wild ancestors of present-day cultivated tomato produce a plethora of acylsugars in their type-I/IV trichomes and volatiles in their type-VI trichomes that have a potential role in plant resistance against insects. However, metabolic profiles are often complex mixtures making identification of the functionally interesting metabolites challenging. Here, we aimed to identify specialised metabolites from a wide range of wild tomato genotypes that could explain resistance to vector insects whitefly (Bemisia tabaci) and Western flower thrips (Frankliniella occidentalis). We evaluated plant resistance, determined trichome density and obtained metabolite profiles of the glandular trichomes by LC-MS (acylsugars) and GC-MS (volatiles). Using a customised Random Forest learning algorithm, we determined the contribution of specific specialised metabolites to the resistance phenotypes observed. RESULTS: The selected wild tomato accessions showed different levels of resistance to both whiteflies and thrips. Accessions resistant to one insect can be susceptible to another. Glandular trichome density is not necessarily a good predictor for plant resistance although the density of type-I/IV trichomes, related to the production of acylsugars, appears to correlate with whitefly resistance. For type VI-trichomes, however, it seems resistance is determined by the specific content of the glands. There is a strong qualitative and quantitative variation in the metabolite profiles between different accessions, even when they are from the same species. Out of 76 acylsugars found, the random forest algorithm linked two acylsugars (S3:15 and S3:21) to whitefly resistance, but none to thrips resistance. Out of 86 volatiles detected, the sesquiterpene α-humulene was linked to whitefly susceptible accessions instead. The algorithm did not link any specific metabolite to resistance against thrips, but monoterpenes α-phellandrene, α-terpinene and ß-phellandrene/D-limonene were significantly associated with susceptible tomato accessions. CONCLUSIONS: Whiteflies and thrips are distinctly targeted by certain specialised metabolites found in wild tomatoes. The machine learning approach presented helped to identify features with efficacy toward the insect species studied. These acylsugar metabolites can be targets for breeding efforts towards the selection of insect-resistant cultivars.

Oxidative stress tolerance potential of milk thistle ecotypes after supplementation of different plant growth-promoting agents under salinity.

The aim of the present work was to evaluate the effect of different plant growth promoters (PGPs) such as ascorbic acid (500 µM), thiourea (250 µM) and moringa leaf extract (3%) to mitigate salinity stress (120 mM NaCl) in four different milk thistle [Silybum marianum (L.) Gaertn.] ecotypes from Faisalabad (FSD), Gujranwala (GUJ), Kallar Kahar (KK), and Quetta (QTA) under field conditions for two years (2017-2018). In the present study, oxidative stress indicators such as malondialdehyde (MDA) and hydrogen peroxide (H2O2) and activities of different antioxidant enzymes and levels of non-enzymatic antioxidants were significantly differed among ecotypes, salinity, and PGPs. Supplementation with ascorbic acid and moringa leaf extract improved antioxidant defense machinery during the acclimation process against salinity, and milk thistle ecotypes represent their background of ecological zones and inherent tendency to face and confronting stress with improving antioxidant levels to a significant extent in varying ways. Ecotypic variations showed that QTA ecotype Followed by FSD, GUJ, and KK had more antioxidant capacity, with minimum reactive oxygen species production. Interestingly, the correlation data revealed that MDA and H2O2 had a positive correlation with each other and showed a negative correlation with all the enzymatic and non-enzymatic antioxidants.

Random amplified polymorphic DNA and inter simple sequence repeat markers reveals genetic diversity between micro propagated, wild and field cultivated genotypes of Gloriosa superba: an endangered medicinal plant.

Gloriosa superba L., an endangered medicinal plant with global interest due to presence of colchicine, an important alkaloid used in formulations of Indian and Traditional medicine. The plant has become endangered due to its unscientifically exploitation and high medicinal values. In the Present study 10 randomly amplified polymorphic DNA (RAPD) and 6 ISSR markers were employed to assess genetic divergence among micro propagated, wild and field cultivated plants of Gloriosa superba collected from different parts of India. In RAPD analysis, all the 10 accession with 10 RAPD primers amplified 466 fragments, with 96.43 % polymorphism and with an average of 46.6 bands per primer. The size of amplicons varied from 1656 to 100 bp. While, ISSR primers produced 328 fragments of which 298 were polymorphic with an average of 49.7 bands per primer with 91.83% polymorphism. The size of amplicons ranges from 2395 to 181 bp. RAPD, ISSR markers were also assessed by calculating polymorphic information content (PIC) to discriminate the genotypes, Average PIC value for RAPD, ISSR and combined RAPD + ISSR markers obtained was ≤ 0.50 suggesting the informativeness of markers. Jaccard's coefficient ranges from 0.18 to 0.75 (RAPD) and 0.17 to 0.61 (ISSR) and 0.21-0.52 for pooled ISSR and RAPD markers. The clustering pattern based on UPGMA analysis of the genotypes in the combined analysis revealed that the majority of the genotypes remained similar to the ISSR dendrogram, while the RAPD-based dendrogram showed some variation in the clustering of genotypes. The result of PCA scattered plot obtained were in agreement with the UPGMA dendrogram, which further confirms the genetic relationships explain by cluster analysis. Results confirmed that the genotype studied had good genetic diversity and can be used for identification, conservation, and future breeding program of Gloriosa species and consequently for the benefit of the pharmaceutical industries.