Plant phase extraction: A method for enhanced discovery of the RNA-binding proteome and its dynamics in plants.

RNA-binding proteins (RBPs) play critical roles in posttranscriptional gene regulation. Current methods of systematically profiling RBPs in plants have been predominantly limited to proteins interacting with polyadenylated (poly(A)) RNAs. We developed a method called plant phase extraction (PPE), which yielded a highly comprehensive RNA-binding proteome (RBPome), uncovering 2,517 RBPs from Arabidopsis (Arabidopsis thaliana) leaf and root samples with a highly diverse array of RNA-binding domains. We identified traditional RBPs that participate in various aspects of RNA metabolism and a plethora of nonclassical proteins moonlighting as RBPs. We uncovered constitutive and tissue-specific RBPs essential for normal development and, more importantly, revealed RBPs crucial for salinity stress responses from a RBP-RNA dynamics perspective. Remarkably, 40% of the RBPs are non-poly(A) RBPs that were not previously annotated as RBPs, signifying the advantage of PPE in unbiasedly retrieving RBPs. We propose that intrinsically disordered regions contribute to their nonclassical binding and provide evidence that enzymatic domains from metabolic enzymes have additional roles in RNA binding. Taken together, our findings demonstrate that PPE is an impactful approach for identifying RBPs from complex plant tissues and pave the way for investigating RBP functions under different physiological and stress conditions at the posttranscriptional level.

Sugar yield and composition of tubers from Jerusalem Artichoke (Helianthus tuberosus) irrigated with saline waters.

Currently, major biofuel crops are also food crops that demand fertile soils and good-quality water. Jerusalem artichoke (Helianthus tuberosus, Asteraceae) produces high tonnage of tubers that are rich in sugars, mainly in the form of inulin. In this study, plants of the cultivar "White Fuseau" grown under five salinity levels were evaluated for tuber yield. Results indicated that this cultivar is moderately salt-tolerant if the goal is tuber production. Hydraulic pressings of the tubers produced juice that contained 15% (wet weight) or 55% (dry weight) free sugars, with 70% of these in the form of inulin and the rest as fructose, sucrose, and glucose. Importantly, salinity did not affect the total free sugar or inulin content of the tubers. Tubers were composed of about 12% dry washed bagasse (wet weight) or 44% (dry matter basis) and bagasse retained such high quantities of free sugars after pressing that washing was required for complete sugar recovery. Chemical composition analysis of tuber bagasse suggested that it had low lignin content (11-13 wt%), and its structural sugar composition was similar to chicory root bagasse. Because of the high hemicellulose and pectin content of the bagasse, adding xylanase and pectinase to cellulase substantially improved sugar yields from enzymatic hydrolysis compared to at the same protein loading as cellulase alone. In addition to the high total sugar yield of tuber, these first findings on the sugar and lignin content and enzymatic hydrolysis of tuber bagasse can lead to low-cost production of ethanol for transportation fuels.

Flower morphology and floral sequence in Artemisia annua (Asteraceae)1.

UNLABELLED: • PREMISE OF THE STUDY: Artemisia annua produces phytochemicals possessing antimalarial, antitumor, anti-inflammatory, and anthelmintic activities. The main active ingredient, artemisinin, is extremely effective against malaria. Breeding to develop cultivars producing high levels of artemisinin can help meet worldwide demand for artemisinin and its derivatives. However, fundamental reproductive processes, such as the sequence of flowering and fertility, are not well understood and impair breeding and seed propagation programs.• METHODS: Capitulum structure and floral sequence were studied using light and scanning electron microscopy to describe inflorescence architecture, floret opening, and seed set.• KEY RESULTS: Florets are minute and born in capitula containing pistillate ray florets and hermaphroditic disk florets. Ray florets have elongated stigmatic arms that extend prior to disk floret opening. Disk florets exhibit protandry. During the staminate phase, pollen is released within a staminate tube and actively presented with projections at the tip of stigmas as the pistil elongates. During the pistillate phase, stigmatic arms bifurcate and reflex. Stigmas are of the dry type and stain positively for polysaccharides, lipids, and an intact cuticle. Floret numbers vary with genotype, and capitula are predominantly composed of disk florets. Both ray and disk florets produce filled seed.• CONCLUSIONS: Gynomonoecy, early opening of ray florets, and dichogamy of disk florets promote outcrossing in A. annua For breeding and seed development, flowering in genotypes can be synchronized under short days according to the floral developmental stages defined. Floret number and percentage seed fill vary with genotype and may be a beneficial selection criterion.

The effects of combining Artemisia annua and Curcuma longa ethanolic extracts in broilers challenged with infective oocysts of Eimeria acervulina and E. maxima.

Due to an increasing demand for natural products to control coccidiosis in broilers, we investigated the effects of supplementing a combination of ethanolic extracts of Artemisia annua and Curcuma longa in drinking water. Three different dosages of this herbal mixture were compared with a negative control (uninfected), a positive control (infected and untreated), chemical coccidiostats (nicarbazin+narazin and, later, salinomycin), vaccination, and a product based on oregano. Differences in performance (weight gain, feed intake, and feed conversion rate), mortality, gross intestinal lesions and oocyst excretion were investigated. Broilers given chemical coccidiostats performed better than all other groups. Broilers given the two highest dosages of the herbal mixture had intermediate lesion scores caused by Eimeria acervulina, which was higher than in broilers given coccidiostats, but less than in broilers given vaccination, oregano and in negative controls. There was a trend for lower mortality (P = 0·08) in the later stage of the growing period (23-43 days) in broilers given the highest dosage of herbal mixture compared with broilers given chemical coccidiostats. In conclusion, the delivery strategy of the herbal extracts is easy to implement at farm level, but further studies on dose levels and modes of action are needed.

Anthelmintic activity of Artemisia annua L. extracts in vitro and the effect of an aqueous extract and artemisinin in sheep naturally infected with gastrointestinal nematodes.

There is no effective natural alternative control for gastrointestinal nematodes (GIN) of small ruminants, with Haemonchus contortus being the most economically important GIN. Despite frequent reports of multidrug-resistant GIN, there is no new commercial anthelmintic to substitute failing ones. Although trematocidal activity of artemisinin analogs has been reported in sheep, neither artemisinin nor its plant source (Artemisia annua) has been evaluated for anthelmintic activity in ruminants. This study evaluated the anthelmintic activity of A. annua crude extracts in vitro and compared the most effective extract with artemisinin in sheep naturally infected with H. contortus. A. annua leaves extracted with water, aqueous 0.1% sodium bicarbonate, dichloromethane, and ethanol were evaluated in vitro by the egg hatch test (EHT) and with the bicarbonate extract only for the larval development test (LDT) using H. contortus. The A. annua water, sodium bicarbonate (SBE), ethanol, and dichloromethane extracts tested in vitro contained 0.3, 0.6, 4.4, and 9.8% of artemisinin, respectively. The sodium bicarbonate extract resulted in the lowest LC99 in the EHT (1.27 µg/mL) and in a LC99 of 23.8 µg/mL in the LDT. Following in vitro results, the SBE (2 g/kg body weight (BW)) and artemisinin (100 mg/kg BW) were evaluated as a single oral dose in naturally infected Santa Inês sheep. Speciation from stool cultures established that 84-91% of GIN were H. contortus, 8.4-15.6 % were Trichostrongylus sp., and 0.3-0.7% were Oesophagostomum sp. Packed-cell volume and eggs per gram (EPG) of feces were used to test treatment efficacy. The SBE tested in vivo contained no artemisinin, but had a high antioxidant capacity of 2,295 µmol of Trolox equivalents/g. Sheep dosed with artemisinin had maximum feces concentrations 24 h after treatment (126.5 µg/g artemisinin), which sharply decreased at 36 h. By day 15, only levamisole-treated sheep had a significant decrease of 97% in EPG. Artemisinin-treated and SBE-treated sheep had nonsignificant EPG reductions of 28 and 19%, respectively, while sheep in infected/untreated group had an average EPG increase of 95%. Sheep treated with artemisinin and A. annua SBE maintained blood hematocrits throughout the experiment, while untreated/infected controls had a significant reduction in hematocrit. This is the first time oral dose of artemisinin and an aqueous extract of A. annua are evaluated as anthelmintic in sheep. Although oral dose of artemisinin and SBE, at single doses, were ineffective natural anthelmintics, artemisinin analogs with better bioavailability than artemisinin should be tested in vivo, through different routes and in multiple doses. The maintenance of hematocrit provided by artemisinin and A. annua extract and the high antioxidant capacity of the latter suggest that they could be combined with commercial anthelmintics to improve the well-being of infected animals and to evaluate potential synergism.

Understanding the salt overly sensitive pathway in Prunus: Identification and characterization of NHX, CIPK, and CBL genes.

Salinity is a major abiotic stress factor that can significantly impact crop growth, and productivity. In response to salt stress, the plant Salt Overly Sensitive (SOS) signaling pathway regulates the homeostasis of intracellular sodium ion concentration. The SOS1, SOS2, and SOS3 genes play critical roles in the SOS pathway, which belongs to the members of Na+/H+ exchanger (NHX), CBL-interacting protein kinase (CIPK), and calcineurin B-like (CBL) gene families, respectively. In this study, we performed genome-wide identifications and phylogenetic analyses of NHX, CIPK, and CBL genes in six Rosaceae species: Prunus persica, Prunus dulcis, Prunus mume, Prunus armeniaca, Pyrus ussuriensis × Pyrus communis, and Rosa chinensis. NHX, CIPK, and CBL genes of Arabidopsis thaliana were used as controls for phylogenetic analyses. Our analysis revealed the lineage-specific and adaptive evolutions of Rosaceae genes. Our observations indicated the existence of two primary classes of CIPK genes: those that are intron-rich and those that are intron-less. Intron-rich CIPKs in Rosaceae and Arabidopsis can be traced back to algae CIPKs and CIPKs found in early plants, suggesting that intron-less CIPKs evolved from their intron-rich counterparts. This study identified one gene for each member of the SOS signaling pathway in P. persica: PpSOS1, PpSOS2, and PpSOS3. Gene expression analyses indicated that all three genes of P. persica were expressed in roots and leaves. Yeast two-hybrid-based protein-protein interaction analyses revealed a direct interaction between PpSOS3 and PpSOS2; and between PpSOS2 and PpSOS1C-terminus region. Our findings indicate that the SOS signaling pathway is highly conserved in P. persica.

A Targeted and an Untargeted Metabolomics Approach to Study the Phytochemicals of Tomato Cultivars Grown Under Different Salinity Conditions.

In this study, we evaluated the effect of increasing the salinity of irrigation water on the metabolic content and profiles of two tomato cultivars ('Jaune Flamme' (JF) and 'Red Pear' (RP)) using targeted and untargeted metabolomics approaches. Irrigation of tomato plants was performed with four different salt concentrations provided by chloride (treatment 1) and sulfate (treatment 2) salts. Targeted analysis of the methanolic extract resulted in the identification of nine major polyphenols. Among them, chlorogenic acid, rutin, and naringenin were the prominent compounds in both cultivars. In addition, the quantification of 18 free amino acids from both tomato cultivars showed that different salinity treatments significantly enhanced the levels of glutamine, glutamic acid, and γ-aminobutyric acid (GABA). Using the untargeted metabolomic approach, we identified 129 putative metabolites encompassing a diverse array of phytochemicals including polyphenols, organic acids, lipids, sugars, and amino acids. Principal component analysis (PCA) of mass spectral data acquired under positive and negative ionization modes showed a clear separation between the two cultivars. However, only positive ionization showed separation among different salinity treatments. Unsupervised and supervised learning algorithms were applied to mine the generated data and to pinpoint metabolites different from the two cultivars. These findings suggest that different salinity conditions significantly influenced the accumulation of phytochemicals in tomato cultivars. This study will help tomato breeding programs to develop value-added tomato cultivars under varying environmental conditions.

Dissemination of antibiotic resistance genes through soil-plant-earthworm continuum in the food production environment.

Treated municipal wastewater (TMW) can provide a reliable source of irrigation water for crops, which is especially important in arid areas where water resources are limited or prone to drought. Nonetheless, TMW may contain residual antibiotics, potentially exposing the crops to these substances. The goal of this study was to investigate the dissemination of antibiotics resistance genes (ARGs) in the soil-plant-earthworm continuum after irrigation of spinach and radish plants with TMW containing trimethoprim, sulfamethoxazole, and sulfapyridine in a greenhouse experiment, followed by feeding of earthworms with harvested plant materials. Our results showed that antibiotic resistance genes (ARGs) were enriched in the soil-plant-earthworm microbiomes irrigated with TMW and TMW spiked with higher concentrations of antibiotics. The number of ARGs and antibiotic-resistant bacteria (ARB) enrichment varied with plant type, with spinach harboring a significantly higher amount of ARGs and ARB compared to radish. Our data showed that bulk and rhizosphere soils of spinach and radish plants irrigated with MilliQ water, TMW, TMW10, or TMW100 had significant differences in bacterial community (p < 0.001), ARG (p < 0.001), and virulence factor gene (VFG) (p < 0.001) diversities. The abundance of ARGs significantly decreased from bulk soil to rhizosphere to phyllosphere and endosphere. Using metagenome assembled genomes (MAGs), we recovered many bacterial MAGs and a near complete genome (>90 %) of bacterial MAG of genus Leclercia adecarboxylata B from the fecal microbiome of earthworm that was fed harvested radish tubers and spinach leaves grown on TMW10 irrigated waters, and this bacterium has been shown to be an emerging pathogen causing infection in immunocompromised patients that may lead to health complications and death. Therefore, crops irrigated with TMW containing residual antibiotics and ARGs may lead to increased incidences of enrichment of ARB in the soil-plant-earthworm continuum.

Dissemination of antimicrobial resistance in agricultural ecosystems following irrigation with treated municipal wastewater.

The spread of antimicrobial resistance (AMR) in agricultural systems via irrigation water is a serious public health issue as it can be transmitted to humans through the food chain. Therefore, understanding the dissemination routes of antibiotic resistance genes (ARGs) in agricultural systems is crucial for the assessment of health risks associated with eating fresh vegetables such as spinach and radish irrigated with treated municipal wastewater (TMW). In this study, we investigated the bacterial community structure and resistome in the soil-plant-earthworm continuum after irrigation of spinach and radish with TMW containing the antibiotics trimethoprim (TMP), sulfamethoxazole (SMZ), and sulfapyridine (SPD) using 16S rRNA gene sequencing and high throughput quantitative PCR (HT-qPCR). The study was conducted in two phases: Phase I involved eight weeks of spinach and radish production using TMW for irrigation, whereas Phase II entailed three weeks of earthworm exposure to contaminated plant material obtained in Phase I. The 16S data indicated that the rhizosphere bacterial community composition and structure were more resilient to antibiotic residuals in the irrigated water, with radish showing less susceptibility than spinach than those of bulk soils. The HT-qPCR analysis revealed that a total of 271 ARGs (out of 285) and 9 mobile genetic elements (MGEs) (out of 10) were detected in all samples. Higher diversity and abundance of ARGs were observed for samples irrigated with higher concentrations of antibiotics in both spinach and radish treatments. However, compared to spinach, radish ARG dynamics in the soil biome were more stable due to the change of antibiotic introduction to the soil. At the class level, multi-drug resistance (MDR) class was altered significantly by the presence of antibiotics in irrigation water. Compared to earthworm fecal samples, their corresponding soil environments showed a higher number of detected ARGs, suggesting that earthworms could play a role in reducing ARG dissemination in the soil environments. These findings will not only provide insight into the dissemination of ARGs in agricultural environments due to antibiotic residuals in irrigated water but could help understand the potential human health risks associated with ARGs.

Dissemination of antibiotics through the wastewater-soil-plant-earthworm continuum.

Under the ongoing climate change scenario, treated municipal wastewater (TMW) is a potential candidate for irrigated agriculture but may result in the exposure of agricultural environments to antibiotics. We studied the transfers of trimethoprim, sulfamethoxazole, and sulfapyridine in the TMW-soil-plant-earthworm continuum under greenhouse/laboratory conditions. Irrigation of potted spinach and radish with as-collected TMW resulted in no transfers of antibiotics into soil or plants owing to their low concentrations in the tertiary-treated TMW. However, TMW spiked with higher antibiotic concentrations led to transfers through this continuum. High initial inputs, slow soil degradation, and chemical speciation of the antibiotics, coupled with an extensive plant-root distribution, were important factors enhancing the plant uptake of antibiotics. In microcosm studies, transfers from vegetable materials into earthworms were low but showed potential for bioaccumulation. Such food chain transfers of antibiotics may be a driver for antibiotic resistance in agricultural systems, which is an area worthy of future study. These issues can perhaps be mitigated through high levels of TMW purification to effectively remove antibiotic compounds.

Deciphering Molecular Mechanisms Involved in Salinity Tolerance in Guar (Cyamopsis tetragonoloba (L.) Taub.) Using Transcriptome Analyses.

Guar is a commercially important legume crop known for guar gum. Guar is tolerant to various abiotic stresses, but the mechanisms involved in its salinity tolerance are not well established. This study aimed to understand molecular mechanisms of salinity tolerance in guar. RNA sequencing (RNA-Seq) was employed to study the leaf and root transcriptomes of salt-tolerant (Matador) and salt-sensitive (PI 340261) guar genotypes under control and salinity. Our analyses identified a total of 296,114 unigenes assembled from 527 million clean reads. Transcriptome analysis revealed that the gene expression differences were more pronounced between salinity treatments than between genotypes. Differentially expressed genes associated with stress-signaling pathways, transporters, chromatin remodeling, microRNA biogenesis, and translational machinery play critical roles in guar salinity tolerance. Genes associated with several transporter families that were differentially expressed during salinity included ABC, MFS, GPH, and P-ATPase. Furthermore, genes encoding transcription factors/regulators belonging to several families, including SNF2, C2H2, bHLH, C3H, and MYB were differentially expressed in response to salinity. This study revealed the importance of various biological pathways during salinity stress and identified several candidate genes that may be used to develop salt-tolerant guar genotypes that might be suitable for cultivation in marginal soils with moderate to high salinity or using degraded water.

Morphological, physiological, biochemical, and transcriptome studies reveal the importance of transporters and stress signaling pathways during salinity stress in Prunus.

The almond crop has high economic importance on a global scale, but its sensitivity to salinity stress can cause severe yield losses. Salt-tolerant rootstocks are vital for crop economic feasibility under saline conditions. Two commercial rootstocks submitted to salinity, and evaluated through different parameters, had contrasting results with the survival rates of 90.6% for 'Rootpac 40' (tolerant) and 38.9% for 'Nemaguard' (sensitive) under salinity (Electrical conductivity of water = 3 dS m-1). Under salinity, 'Rootpac 40' accumulated less Na and Cl and more K in leaves than 'Nemaguard'. Increased proline accumulation in 'Nemaguard' indicated that it was highly stressed by salinity compared to 'Rootpac 40'. RNA-Seq analysis revealed that a higher degree of differential gene expression was controlled by genotype rather than by treatment. Differentially expressed genes (DEGs) provided insight into the regulation of salinity tolerance in Prunus. DEGs associated with stress signaling pathways and transporters may play essential roles in the salinity tolerance of Prunus. Some additional vital players involved in salinity stress in Prunus include CBL10, AKT1, KUP8, Prupe.3G053200 (chloride channel), and Prupe.7G202700 (mechanosensitive ion channel). Genetic components of salinity stress identified in this study may be explored to develop new rootstocks suitable for salinity-affected regions.

In vitro trematocidal effects of crude alcoholic extracts of Artemisia annua, A. absinthium, Asimina triloba, and Fumaria officinalis: trematocidal plant alcoholic extracts.

Trematode infections negatively affect human and livestock health, and threaten global food safety. The only approved human anthelmintics for trematodiasis are triclabendazole and praziquantel with no alternative drugs in sight. We tested six crude plant extracts against adult Schistosoma mansoni, Fasciola hepatica, and Echinostoma caproni in vitro. Mortality was best achieved by ethanolic extracts of Artemisia annua (sweet Annie), Asimina triloba (paw-paw), and Artemisia absinthium (wormwood) which, at 2 mg/mL, killed S. mansoni and E. caproni in 20 h or less (except for wormwood), F. hepatica between 16 and 23 h (sweet Annie), or 40 h (paw-paw). Some extracts were active at 0.2 mg/mL and 20 µg/mL, although more time was required to kill trematodes. However, aqueous A. annua and methanol extracts of Fumaria officinalis had no activity. Chromatographic analysis of the three best extracts established that A. annua and A. triloba extracts contained bioactive artemisinin and acetogenins (asimicin and bullatacin), respectively. The anthelmintic activity of our extracts at such low doses indicates that their anthelmintic activity deserves further testing as natural alternative controls for parasites of both animals and humans. Our results also support recent evidence that synergistic effects of multiple bioactive compounds present in crude plant extracts is worth exploring.

Linking genetic determinants with salinity tolerance and ion relationships in eggplant, tomato and pepper.

The Solanaceae family includes commercially important vegetable crops characterized by their relative sensitivity to salinity. Evaluation of 8 eggplant (Solanum melongena), 7 tomato (Solanum lycopersicum), and 8 pepper (Capsicum spp.) heirloom cultivars from different geographic regions revealed significant variation in salt tolerance. Relative fruit yield under salt treatment varied from 52 to 114% for eggplant, 56 to 84% for tomato, and 52 to 99% for pepper. Cultivars from all three crops, except Habanero peppers, restricted Na transport from roots to shoots under salinity. The high salt tolerance level showed a strong association with low leaf Na concentration. Additionally, the leaf K-salinity/K-control ratio was critical in determining the salinity tolerance of a genotype. Differences in relative yield under salinity were regulated by several component traits, which was consistent with the gene expression of relevant genes. Gene expression analyses using 12 genes associated with salt tolerance showed that, for eggplant and pepper, Na+ exclusion was a vital component trait, while sequestration of Na+ into vacuoles was critical for tomato plants. The high variability for salt tolerance found in heirloom cultivars helped characterize genotypes based on component traits of salt tolerance and will enable breeders to increase the salt tolerance of Solanaceae cultivars.

Influence of seasonal changes and salinity on spinach phyllosphere bacterial functional assemblage.

The phyllosphere is the aerial part of plants that is exposed to different environmental conditions and is also known to harbor a wide variety of bacteria including both plant and human pathogens. However, studies on phyllosphere bacterial communities have focused on bacterial composition at different stages of plant growth without correlating their functional capabilities to bacterial communities. In this study, we examined the seasonal effects and temporal variabilities driving bacterial community composition and function in spinach phyllosphere due to increasing salinity and season and estimated the functional capacity of bacterial community16S V4 rRNA gene profiles by indirectly inferring the abundance of functional genes based on metagenomics inference tool Piphillin. The experimental design involved three sets of spinach (Spinacia oleracea L., cv. Racoon) grown with saline water during different seasons. Total bacteria DNA from leaf surfaces were sequenced using MiSeq® Illumina platform. About 66.35% of bacteria detected in the phyllosphere were dominated by four phyla- Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria. Permutational analysis of variance (PERMANOVA) showed that phyllosphere microbiomes were significantly (P < 0.003) affected by season, but not salinity (P = 0.501). The most abundant inferred functional pathways in leaf samples were the amino acids biosynthesis, ABC transporters, ribosome, aminoacyl-tRNA biosynthesis, two-component system, carbon metabolism, purine metabolism, and pyrimidine metabolism. The photosynthesis antenna proteins pathway was significantly enriched in June leaf samples, when compared to March and May. Several genes related to toxin co-regulated pilus biosynthesis proteins were also significantly enriched in June leaf samples, when compared to March and May leaf samples. Therefore, planting and harvesting times must be considered during leafy green production due to the influence of seasons in growth and proliferation of phyllosphere microbial communities.

Transcriptional profiling of two contrasting genotypes uncovers molecular mechanisms underlying salt tolerance in alfalfa.

Alfalfa is an important forage crop that is moderately tolerant to salinity; however, little is known about its salt-tolerance mechanisms. We studied root and leaf transcriptomes of a salt-tolerant (G03) and a salt-sensitive (G09) genotype, irrigated with waters of low and high salinities. RNA sequencing led to 1.73 billion high-quality reads that were assembled into 418,480 unigenes; 35% of which were assigned to 57 Gene Ontology annotations. The unigenes were assigned to pathway databases for understanding high-level functions. The comparison of two genotypes suggested that the low salt tolerance index for transpiration rate and stomatal conductance of G03 compared to G09 may be due to its reduced salt uptake under salinity. The differences in shoot biomass between the salt-tolerant and salt-sensitive lines were explained by their differential expressions of genes regulating shoot number. Differentially expressed genes involved in hormone-, calcium-, and redox-signaling, showed treatment- and genotype-specific differences and led to the identification of various candidate genes involved in salinity stress, which can be investigated further to improve salinity tolerance in alfalfa. Validation of RNA-seq results using qRT-PCR displayed a high level of consistency between the two experiments. This study provides valuable insight into the molecular mechanisms regulating salt tolerance in alfalfa.

Flavonoids from Artemisia annua L. as antioxidants and their potential synergism with artemisinin against malaria and cancer.

Artemisia annua is currently the only commercial source of the sesquiterpene lactone artemisinin.Since artemisinin was discovered as the active component of A. annua in early 1970s, hundreds of papers have focused on the anti-parasitic effects of artemisinin and its semi-synthetic analogs dihydroartemisinin, artemether, arteether, and artesunate. Artemisinin per se has not been used in mainstream clinical practice due to its poor bioavailability when compared to its analogs. In the past decade, the work with artemisinin-based compounds has expanded to their anti-cancer properties. Although artemisinin is a major bioactive component present in the traditional Chinese herbal preparations (tea), leaf flavonoids, also present in the tea, have shown a variety of biological activities and may synergize the effects of artemisinin against malaria and cancer. However, only a few studies have focused on the potential synergistic effects between flavonoids and artemisinin. The resurgent idea that multi-component drug therapy might be better than monotherapy is illustrated by the recent resolution of the World Health Organization to support artemisinin-based combination therapies (ACT), instead of the previously used monotherapy with artemisinins. In this critical review we will discuss the possibility that artemisinin and its semi-synthetic analogs might become more effective to treat parasitic diseases (such as malaria) and cancer if simultaneously delivered with flavonoids. The flavonoids present in A. annua leaves have been linked to suppression of CYP450 enzymes responsible for altering the absorption and metabolism of artemisinin in the body, but also have been linked to a beneficial immunomodulatory activity in subjects afflicted with parasitic and chronic diseases.

Spinach Plants Favor the Absorption of K+ over Na+ Regardless of Salinity, and May Benefit from Na+ When K+ is Deficient in the Soil.

Two spinach (Spinacea oleracea L.) cultivars were evaluated for their response to deficient (0.25 mmolc L-1 or 0.25 K) and sufficient (5.0 mmolc L-1 or 5.0 K) potassium (K) levels combined with salinities of 5, 30, 60, 90, and 120 mmolc L-1 NaCl. Plants substituted K for Na proportionally with salinity within each K dose. Plants favored K+ over Na+, regardless of salinity, accumulating significantly less Na at 5.0 K than at 0.25 K. Salinity had no effect on N, P, and K shoot accumulation, suggesting that spinach plants can maintain NPK homeostasis even at low soil K. Ca and Mg decreased with salinity, but plants showed no deficiency. There was no Na+ to K+ or Cl- to NO3- competition, and shoot biomass decrease was attributed to excessive NaCl accumulation. Overall, 'Raccoon' and 'Gazelle' biomasses were similar regardless of K dose but 'Raccoon' outproduced 'Gazelle' at 5.0 K at the two highest salinity levels, indicating that 'Raccoon' may outperform 'Gazelle' at higher NaCl concentrations. At low K, Na may be required by 'Raccoon', but not 'Gazelle'. This study suggested that spinach can be cultivated with recycled waters of moderate salinity, and less potassium than recommended, leading to savings on crop input and decreasing crop environmental footprint.

Functional relationships between aboveground and belowground spinach (Spinacia oleracea L., cv. Racoon) microbiomes impacted by salinity and drought.

Salinity is a major problem facing agriculture in arid and semiarid regions of the world. This problem may vary among seasons affecting both above- and belowground plant microbiomes. However, very few studies have been conducted to examine the influence of salinity and drought on microbiomes and on their functional relationships. The objective for the study was to examine the effects of salinity and drought on above- and belowground spinach microbiomes and evaluate seasonal changes in their bacterial community composition and diversity. Furthermore, potential consequences for community functioning were assessed based on 16S V4 rRNA gene profiles by indirectly inferring the abundance of functional genes based on results obtained with Piphillin. The experiment was repeated three times from early fall to late spring in sand tanks planted with spinach (Spinacia oleracea L., cv. Racoon) grown with saline water of different concentrations and provided at different amounts. Proteobacteria, Cyanobacteria, and Bacteroidetes accounted for 77.1% of taxa detected in the rhizosphere; Proteobacteria, Bacteroidetes, and Actinobacteria accounted for 55.1% of taxa detected in soil, while Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria accounted for 55.35% of taxa detected in the phyllosphere. Salinity significantly affected root microbiome beta-diversity according to weighted abundances (p = 0.032) but had no significant effect on the relative abundances of microbial taxa (p = 0.568). Pathways and functional genes analysis of soil, rhizosphere, and phyllosphere showed that the most abundant functional genes were mapped to membrane transport, DNA repair and recombination, signal transduction, purine metabolism, translation-related protein processing, oxidative phosphorylation, bacterial motility protein secretion, and membrane receptor proteins. Monoterpenoid biosynthesis was the most significantly enriched pathway in rhizosphere samples when compared to the soil samples. Overall, the predictive abundances indicate that, functionally, the rhizosphere bacteria had the highest gene abundances and that salinity and drought affected the above- and belowground microbiomes differently.

Linking diverse salinity responses of 14 almond rootstocks with physiological, biochemical, and genetic determinants.

Fourteen commercial almond rootstocks were tested under five types of irrigation waters to understand the genetic, physiological, and biochemical bases of salt-tolerance mechanisms. Treatments included control (T1) and four saline water treatments dominant in sodium-sulfate (T2), sodium-chloride (T3), sodium-chloride/sulfate (T4), and calcium/magnesium-chloride/sulfate (T5). T3 caused the highest reduction in survival rate and trunk diameter, followed by T4 and T2, indicating that Na and, to a lesser extent, Cl were the most toxic ions to almond rootstocks. Peach hybrid (Empyrean 1) and peach-almond hybrids (Cornerstone, Bright's Hybrid 5, and BB 106) were the most tolerant to salinity. Rootstock's performance under salinity correlated highly with its leaf Na and Cl concentrations, indicating that Na+ and Cl- exclusion is crucial for salinity tolerance in Prunus. Photosynthetic rate correlated with trunk diameter and proline leaf ratio (T3/T1) significantly correlated with the exclusion of Na+ and Cl-, which directly affected the survival rate. Expression analyses of 23 genes involved in salinity stress revealed that the expression differences among genotypes were closely associated with their performance under salinity. Our genetic, molecular, and biochemical analyses allowed us to characterize rootstocks based on component traits of the salt-tolerance mechanisms, which may facilitate the development of highly salt-tolerant rootstocks.