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Recent quasar absorption line observations suggest that reionization may end as late as |$z \approx 5.3$|⁠. As a means to search for large neutral hydrogen islands at |$z\ \lt\ 6$|⁠ , we revisit long dark gaps in the Ly  |$\beta$| forest in Very Large Telescope/X-Shooter and Keck/Echellette Spectrograph and Imager quasar spectra. We stack the Ly  |$\alpha$| forest corresponding to both edges of these Ly  |$\beta$| dark gaps and identify a damping wing-like extended absorption profile. The average redshift of the stacked forest is |$z=5.8$|⁠. By comparing these observations with reionization simulations, we infer that such a damping wing-like feature can be naturally explained if these gaps are at least partially created by neutral islands. Conversely, simulated dark gaps lacking neutral hydrogen struggle to replicate the observed damping wing features. Furthermore, this damping wing-like profile implies that the volume-averaged neutral hydrogen fraction must be |$\langle x_{\rm H\,{\small {I}}} \rangle \ge 6.1 \pm 3.9~{{\ \rm per\ cent}}$| at |$z = 5.8$|⁠. Our results offer robust evidence that reionization extends below |$z=6$|⁠. [ABSTRACT FROM AUTHOR]

We measure the mean free path (⁠|$\lambda _{\rm mfp,H\, \small {I}}$|⁠), photoionization rate (⁠|$\langle \Gamma _{\rm H\, \small {I}} \rangle$|⁠), and neutral fraction (⁠|$\langle f_{\rm H\, \small {I}} \rangle$|⁠) of hydrogen in 12 redshift bins at 4.85 < z < 6.05 from a large sample of moderate resolution XShooter and ESI QSO absorption spectra. The fluctuations in ionizing radiation field are modelled by post-processing simulations from the Sherwood suite using our new code 'EXtended reionization based on the Code for Ionization and Temperature Evolution' (ex-cite). ex-cite uses efficient Octree summation for computing intergalactic medium attenuation and can generate large number of high resolution |$\Gamma _{\rm H\, \small {I}}$| fluctuation models. Our simulation with ex-cite shows remarkable agreement with simulations performed with the radiative transfer code Aton and can recover the simulated parameters within 1σ uncertainty. We measure the three parameters by forward-modelling the  Lyα forest and comparing the effective optical depth (⁠|$\tau _{\rm eff, H\, \small {I}}$|⁠) distribution in simulations and observations. The final uncertainties in our measured parameters account for the uncertainties due to thermal parameters, modelling parameters, observational systematics, and cosmic variance. Our best-fitting parameters show significant evolution with redshift such that |$\lambda _{\rm mfp,H\, \small {I}}$| and |$\langle f_{\rm H\, \small {I}} \rangle$| decreases and increases by a factor ∼6 and ∼104, respectively from z ∼ 5 to z ∼ 6. By comparing our |$\lambda _{\rm mfp,H\, \small {I}}$|⁠ , |$\langle \Gamma _{\rm H\, \small {I}} \rangle$| and |$\langle f_{\rm H\, \small {I}} \rangle$| evolution with that in state-of-the-art Aton radiative transfer simulations and the Thesan and CoDa-III simulations, we find that our best-fitting parameter evolution is consistent with a model in which reionization completes by z ∼ 5.2. Our best-fitting model that matches the |$\tau _{\rm eff, H\, \small {I}}$| distribution also reproduces the dark gap length distribution and transmission spike height distribution suggesting robustness and accuracy of our measured parameters. [ABSTRACT FROM AUTHOR]

In the Tibetan Plateau grassland ecosystems, nitrogen (N) availability is rising dramatically; however, the influence of higher N on the arbuscular mycorrhizal fungi (AMF) might impact on plant competitive interactions. Therefore, understanding the part played by AMF in the competition between Vicia faba and Brassica napus and its dependence on the N-addition status is necessary. To address this, a glasshouse experiment was conducted to examine whether the grassland AMF community's inocula (AMF and NAMF) and N-addition levels (N-0 and N-15) alter plant competition between V. faba and B. napus. Two harvests took day 45 (1st harvest) and day 90 (2nd harvest), respectively. The findings showed that compared to B. napus, AMF inoculation significantly improved the competitive potential of the V. faba. In the occurrence of AMF, V. faba was the strongest competitor being facilitated by B. napus in both harvests. While under N-15, AMF significantly enhanced tissue N:P ratio in B. napus mixed-culture at 1st harvest, the opposite trend was observed in 2nd harvest. The mycorrhizal growth dependency slightly negatively affected mixed-culture compared to monoculture under both N-addition treatments. The aggressivity index of AMF plants was higher than NAMF plants with both N-addition and harvests. Our observation highlights that mycorrhizal associations might facilitate host plant species in mixed-culture with non-host plant species. Additionally, interacting with N-addition, AMF could impact the competitive ability of the host plant not only directly but also indirectly, thereby changing the growth and nutrient uptake of competing plant species. [ABSTRACT FROM AUTHOR]

We examine the column density distribution function (CDDF) and Doppler parameter distribution from hydrodynamical simulations and Cosmic Origins Spectrograph (COS) observations of the Ly α forest at redshift 0 ≤ z ≤ 0.2. Allowing for a factor of two uncertainty in the metagalactic H  |$\, \rm \scriptstyle I \, $| photoionization rate, our hydrodynamical simulations are in good agreement (1–1.5σ) with the shape and amplitude of the observed CDDF at H  |$\, \rm \scriptstyle I \, $| column densities |$10^{13.3}\rm \, cm^{-2}\le N_{\rm H\,{\small I}}\le 10^{14.5}\rm \, cm^{-2}$|⁠. However, the Doppler widths of the simulated lines remain too narrow with respect to the COS data. We argue that invoking AGN feedback does not resolve this discrepancy. We also disfavour enhanced photoheating rates as a potential solution, as this requires an unphysically hard UV background spectrum. If instead appealing to a non-canonical source of heating, an additional specific heat injection of |$u \lesssim 6.9\rm \, eV\, m_{\rm p}^{-1}$| is required at z ≲ 2.5 for gas that has |$N_{\rm H\,{\small I}}\simeq 10^{13.5}\rm \, cm^{-2}$| by z  = 0.1. Alternatively, there may be an unresolved line of sight turbulent velocity component of |$v_{\rm turb}\lesssim 8.5\rm \, km\, s^{-1}(N_{\rm H\,{\small I}}/10^{13.5}\rm \, cm^{-2})^{0.21}$| for the coldest gas in the diffuse IGM. [ABSTRACT FROM AUTHOR]

American ginseng (Panax quinquefolium L.) is a perennial plant that is cultivated for medicinal purposes. Unfortunately, outbreaks of root rot disease in American ginseng (AG) reduce yields and result in serious economic losses. Information on the dynamics of soil microbial communities associated with healthy and diseased AG of different ages is limited. The present study explored the differences in field soil microbial community structure, composition, interaction, and their predictive functions associated with healthy and diseased AG at different growth ages. Changes in soil physicochemical properties were also examined to determine the possible reasons for disease outbreaks. Results revealed that in different growth years, the genera of soil-borne pathogens, such as Alternaria , Botrytis , Cladosporium , Sarocladium , and Fusarium , were increased in diseased AG soil samples in comparison with those in the healthy AG soil samples. In contrast, the abundance of some key and potentially beneficial microbes, such as Bacillus , Chaetomium , Dyella , Kaistobacter , Paenibacillus , Penicillium , and Trichoderma , was decreased. Additionally, as AG plants age, the relative abundance of symbiotic fungi tended to decrease, while the relative abundance of potential plant pathogenic fungi gradually increased. Various soil properties, such as available phosphorus, the ratio of total nitrogen to total phosphorus (N/P), and pH, were significantly (P < 0.05) associated with microbial community composition. Our findings provide a scientific basis for understanding the relationship among the root rot disease outbreaks in American ginseng as well as their corresponding soil microbial communities and soil physicochemical properties. [ABSTRACT FROM AUTHOR]

More than 80% of land plant species benefit from symbiotic partnerships with arbuscular mycorrhizal (AM) fungi, which assist in nutrient acquisition and enhance the ability of host plants to adapt to environmental constraints. Host-generated plasma membrane-residing receptor-like kinases and the intracellular α/β-hydrolase DWARF14-LIKE, a putative karrikin receptor, detect the presence of AM fungi before physical contact between the host and fungus. Detection induces appropriate symbiotic responses, which subsequently enables a favorable environment for AM symbiosis to occur. To prevent hyper-colonization and maintain a mutually beneficial association, the host plant precisely monitors and controls AM colonization by receptor-like kinases, such as SUPER NUMERIC NODULES. Previous studies have elucidated how host plant receptors and receptor-mediated signaling regulate AM symbiosis, but the underlying molecular mechanisms remain poorly understood. The identification of a rice CHITIN ELICITOR RECEPTOR KINASE 1 interaction partner, MYC FACTOR RECEPTOR 1, and new insights into DWARF14-LIKE receptor- and SUPER NUMERIC NODULES receptor-mediated signaling have expanded our understanding of how host plant receptors and their corresponding signals regulate AM symbiosis. This review summarizes these and other recent relevant findings. The identified receptors and/or their signaling components could be manipulated to engineer crops with improved agronomic traits by conferring the ability to precisely control AM colonization. [ABSTRACT FROM AUTHOR]

The rhizosphere fungal community affects the ability of crops to acquire nutrients and their susceptibility to pathogen invasion. However, the effects of rice domestication on the diversity and interactions of rhizosphere fungal community still remain largely unknown. Here, internal transcribed spacer amplicon sequencing was used to systematically analyze the structure of rhizosphere fungal communities of wild and domesticated rice. The results showed that domestication increased the alpha diversity indices of the rice rhizosphere fungal community. The changes of alpha diversity index may be associated with the enrichment of Acremonium , Lecythophora , and other specific rare taxa in the rhizosphere of domesticated rice. The co-occurrence network showed that the complexity of wild rice rhizosphere fungal community was higher than that of the domesticated rice rhizosphere fungal community. Arbuscular mycorrhizal fungi (AMF) and soilborne fungi were positively and negatively correlated with more fungi in the wild rice rhizosphere, respectively. For restructuring the rhizomicrobial community of domesticated crops, we hypothesize that microbes that hold positive connections with AMF and negative connections with soilborne fungi can be used as potential sources for bio-inoculation. Our findings provide a scientific basis for reshaping the structure of rhizomicrobial community and furthermore create potential for novel intelligent and sustainable agricultural solutions. [ABSTRACT FROM AUTHOR]

A recent study by Choi et al. provides evidence of the interaction between the karrikin (KAR) signaling and strigolactone (SL) biosynthetic pathways. Since SLs shape rhizomicrobiome composition, it is of interest to determine whether KAR signaling could affect rhizomicrobiome composition by improving the synthesis of root-derived SLs to support climate-smart agriculture. [ABSTRACT FROM AUTHOR]

Previous studies have noted difficulties in modelling the highest opacities of the z > 5.5 Ly α forest, epitomized by the extreme Lyα trough observed towards quasar ULAS J0148 + 0600. One possibility is that the most opaque regions at these redshifts contain significant amounts of neutral hydrogen. This explanation, which abandons the common assumption that reionization ended before z  = 6, also reconciles evidence from independent observations of a significantly neutral Universe at z  = 7.5. Here, we explore a model in which the neutral fraction is still |${\approx }10{{\ \rm per\ cent}}$| at z  = 5.5. We confirm that this model can account for the observed scatter in Ly α forest opacities, as well as the observed Ly β transmission in the J0148 trough. We contrast the model with a competing 'earlier' reionization scenario characterized by a short mean free path and large fluctuations in the post-reionization ionizing background. We consider Ly α and Ly β effective optical depths, their correlations, trough size distributions, dark pixel fractions, the IGM thermal history, and spatial distributions of Lyman-α emitters around forest sightlines. We find that the models are broadly similar in almost all of these statistics, suggesting that it may be difficult to distinguish between them definitively. We argue that improved constraints on the mean free path and the thermal history at z > 5 could go a long way towards diagnosing the origin of the z > 5.5 opacity fluctuations. [ABSTRACT FROM AUTHOR]

• Strigolactone (SL) phytohormones determine the rhizomicrobiome in rice. • SL-mediated metabolic pathways are likely to be responsible for the regulation of rhizomicrobiome in rice. • Genetic modulation of rice SL biosynthesis and/or signaling may promote the abundance of specific beneficial bacterial taxa. The rhizomicrobiome helps the host plant to better adapt to environmental stresses. In contrast, plant-derived metabolic substances, including phytohormones, play an active role in structuring rhizomicrobiome. Although strigolactones (SLs), a group of phytohormones, serve as potential rhizosphere signaling molecules, their contributions in shaping the rice (Oryza sativa) rhizomicrobiome remain elusive. To address this issue, we compared the rhizomicrobiome of rice mutants defective in either SL biosynthesis or signaling and wild-type (WT) plants. To understand whether SL-regulated metabolic pathways shape the rhizomicrobiome, a correlation network analysis was conducted among the metabolic pathway-related genes and the rhizomicrobiome of rice. Compared to WT, higher bacterial richness (evidenced by the operational taxonomic unit richness) and lower fungal diversity (evidenced by the Shannon index) were observed in both SL deficient dwarf17 (d17) and signaling (d14) mutants. Additionally, remarkable differences were observed in the composition of a large number of bacterial communities than the fungal communities in the d17 and d14 mutants with respect to the WT. The abundance of certain beneficial bacterial taxa, including Nitrosomonadaceae and Rhodanobacter , were significantly decreased in both mutants relative to the WT. Correlation network analysis between SL-regulated metabolic pathway-associated genes and rhizomicrobiome proposed a role for SL-dependent metabolic pathways in shaping rhizomicrobiome composition. Taken together, our study suggests that SL biosynthesis and signaling play a key role in determining the rice rhizomicrobiome, directly or indirectly, through the mediation of distinct metabolic pathways. Based on our findings, the genetic modulation of rice SL biosynthesis and/or signaling pathways may help to recruit/increase the abundance of the desired rhizomicrobiome, which may assist in the stress resilience of rice. [ABSTRACT FROM AUTHOR]

This study presents evidence that strigolactones (SLs) promote defense against devastating rice blast fungal pathogen Magnaporthe oryzae. Impairment in either SL-biosynthetic dwarf17 (d17) or –signaling (d14) led to increased susceptibility towards M. oryzae. Comparative transcriptome profiling of the SL-signaling d14 mutant and WT plants revealed that a large number of defense-associated genes including hydrogen peroxide (H 2 O 2)-, ethylene- and cell wall-synthesis-related genes were remarkably suppressed in d14 with respect to that of WT plants, during M. oryzae infection. In addition, various KEGG metabolic pathways related to sugar metabolism were significantly suppressed in the d14 plants compared to WT, during M. oryzae infection. Accordingly, WT plants accumulated increased levels of H 2 O 2 and soluble sugar content compared to that of d17 and d14 in response to M. oryzae infection. Altogether, these results propose that SLs positively regulated rice defense against M. oryzae through involvement in the induction of various defense associated genes/pathways. • Strigolactone (SL) synthesis and signaling enhance resistance against rice blast infection. • RNA-sequencing revealed SL-mediated defense-related genes/pathways against blast infection. • SLs may serve as a novel target to improve rice defense against blast infection. [ABSTRACT FROM AUTHOR]

Cultivated soybean (Glycine max) was derived from the wild soybean (Glycine soja), which has genetic resources that can be critically important for improving plant stress resistance. However, little information is available pertaining to the molecular and physiochemical comparison between the cultivated and wild soybeans in response to the pathogenic Fusarium oxysporum Schltdl. In this study, we first used comparative phenotypic and paraffin section analyses to indicate that wild soybean is indeed more resistant to F. oxysporum than cultivated soybean. Genome‐wide RNA‐sequencing approach was then used to elucidate the genetic mechanisms underlying the differential physiological and biochemical responses of the cultivated soybean, and its relative, to F. oxysporum. A greater number of genes related to cell wall synthesis and hormone metabolism were significantly altered in wild soybean than in cultivated soybean under F. oxysporum infection. Accordingly, a higher accumulation of lignins was observed in wild soybean than cultivated soybean under F. oxysporum infection. Collectively, these results indicated that secondary metabolites and plant hormones may play a vital role in differentiating the response between cultivated and wild soybeans against the pathogen. These important findings may provide future direction to breeding programs to improve resistance to F. oxysporum in the elite soybean cultivars by taking advantage of the genetic resources within wild soybean germplasm. [ABSTRACT FROM AUTHOR]

Abstract Plant pathogens represent a huge threat to world food security, affecting both crop production and quality. Although significant progress has been made in improving plant immunity by expressing key, defense-related genes and proteins from different species in transgenic crops, a challenge remains for molecular breeders and biotechnologists to successfully engineer elite, transgenic crop varieties with improved resistance against critical plant pathogens. Upon pathogen attack, including infection of rice (Oryza sativa) by Magnaporthe oryzae , host plants initiate a complex defense response at molecular, biochemical and physiological levels. Plants perceive the presence of pathogens by detecting microbe-associated molecular patterns via pattern recognition receptors, and initiate a first line of innate immunity, the so-called pattern-triggered immunity (PTI). This results in a series of downstream defense responses, including the production of hormones, which collectively function to fend off pathogen attacks. A variety of studies have demonstrated that many genes are involved in the defense response of rice to M. oryzae. In this review, the current understanding of mechanisms that improve rice defense response to M. oryzae will be discussed, with special focus on PTI and the phytohormones ethylene, jasmonic acid, salicylic acid, and abscisic acid; as well as on the mediation of defense signaling mechanisms by PTI and these hormones. Potential target genes that may serve as promising candidates for improving rice immunity against M. oryzae will also be discussed. [ABSTRACT FROM AUTHOR]

Abstract: The evidence to support implantable cardioverter defibrillator (ICD) in subjects with nonischemic cardiomyopathy (NICM) for primary prevention of sudden cardiac death (SCD) is not robust. This meta‐analysis intends to assess the impact of routine ICD implantation for primary prevention of mortality due to SCD in NICM based on all the published randomized clinical trials (RCTs). Six RCTs were selected using PubMed/Medline, EMBASE, and CENTRAL from inception to December 2016. Outcomes were calculated as random‐effects relative risk (RR) and risk difference (RD) with 95% confidence interval (CI). Patients were randomized to ICD arm and control arm (usual care, medical treatment, and anti‐arrhythmic drugs). ICD significantly reduced all‐cause mortality in NICM patients (RR, 0.74, 95% CI, 0.56‐0.97, P = .03, I2 = 40). Mortality benefit was achieved due to a significant reduction in sudden cardiac death (SCD) (RR, 0.47, 95% CI, 0.30‐0.73, P < .001, I2 = 0). There were no statistical differences between two groups with regard to risk of noncardiac mortality, non‐SCD, cardiac arrest, cardiac transplant, sustained ventricular tachycardia (VT), and VT requiring medical treatment. Our results support efficacy of ICDs at reducing all‐cause mortality due to a reduction in SCD. [ABSTRACT FROM AUTHOR]

We study the effect of different feedback prescriptions on the properties of the low-redshift (z ≤ 1.6) Lyα forest using a selection of hydrodynamical simulations drawn from the Sherwood simulation suite. The simulations incorporate stellar feedback, active galactic nuclei (AGN) feedback and a simplified scheme for efficiently modelling the low column density Lyα forest. We confirm a discrepancy remains between Cosmic Origins Spectrograph (COS) observations of the Lyα forest column density distribution function (CDDF) at z ≃ 0.1 for high column density systems (NHI > 1014 cm-2), as well as Lyα velocity widths that are too narrow compared to the COS data. Stellar or AGN feedback-as currently implemented in our simulations-has only a small effect on the CDDF and velocity width distribution. We conclude that resolving the discrepancy between the COS data and simulations requires an increase in the temperature of overdense gas with Δ = 4-40, either through additional He IIphotoheating at z > 2 or fine-tuned feedback that ejects overdense gas into the intergalactic medium at just the right temperature for it to still contribute significantly to the Lyα forest. Alternatively a larger, currently unresolved turbulent component to the line width could resolve the discrepancy. [ABSTRACT FROM AUTHOR]

We use cosmological hydrodynamical simulations to assess the feasibility of constraining the thermal history of the intergalactic medium during reionisation with the Lyαα forest at z ≃ 5 . The integrated thermal history has a measureable impact on the transmitted flu≲x power spectrum that can be isolated from Doppler broadening at this redshift. W≃e parameterise this using the cumulative energy per proton, u0, deposited into a gas parcel at the mean background density, a quantity that is tightly linked with the gas density power spectrum in the simulations. We construct mock observations of the line of sight Lyαα forest power spectrum and use a Markov Chain Monte Carlo approach to recover μ0 at redshifts 5≲z≲12. A statistical uncertainty of ∼20 per cent is expected (at 68 per cent confidence) at z ≃ 5 using high resolution spectra with a total redshift path length of ▵ z▵ = 4 and a typical signal-to-noise ratio of S/N=15S/N=15 per pixel. Estimates for the expected systematic uncertainties are comparable, such that existing data should enable a measurement of μ0 to within ∼30 per cent. This translates to distinguishing between reionisation scenarios with similar instantaneous temperatures at z ≃ 5, but with an energy deposited per proton that differs by 2-3eV3eV over the redshift interval 5≲z≲12. For an initial temperature of T∼104 K following reionisation, this corresponds to the difference between early (zre = 12) and late (zre = 7) reionisation in our models. [ABSTRACT FROM AUTHOR]

Bacterial communities in cold-desert habitats play an important ecological role. However, the variation in bacterial diversity and community composition of the cold-desert ecosystem in Qinghai–Tibet Plateau remains unknown. To fill this scientific gape, Illumina MiSeq sequencing was performed on 15 soil samples collected from different cold-desert habitats, including human-disturbed, vegetation coverage, desert land, and sand dune. The abundance-based coverage estimator, Shannon, and Chao indices showed that the bacterial diversity and abundance of the cold-desert were high. A significant variation reported in the bacterial diversity and community composition across the study area. Proteobacteria accounted for the largest proportion (12.4–55.7%) of all sequences, followed by Actinobacteria (9.2–39.7%), Bacteroidetes (1.8–21.5%), and Chloroflexi (2.7–12.6%). Furthermore, unclassified genera dominated in human-disturbed habitats. The community profiles of GeErMu, HongLiangHe, and CuoNaHu sites were different and metagenomic biomarkers were higher (22) in CuoNaHu sites. Among the soil physicochemical variables, the total nitrogen and electric conductivity significantly influenced the bacterial community structure. In conclusion, this study provides information regarding variation in diversity and composition of bacterial communities and elucidates the association between bacterial community structures and soil physicochemical variables in cold-desert habitats of Qinghai–Tibet Plateau. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) establish symbiotic interaction with 80% of known land plants. It has a pronounced impact on plant growth, water absorption, mineral nutrition, and protection from abiotic stresses. Plants are very dynamic systems having great adaptability under continuously changing drying conditions. In this regard, the function of AMF as a biological tool for improving plant drought stress tolerance and phenotypic plasticity, in terms of establishing mutualistic associations, seems an innovative approach towards sustainable agriculture. However, a better understanding of these complex interconnected signaling pathways and AMF-mediated mechanisms that regulate the drought tolerance in plants will enhance its potential application as an innovative approach in environmentally friendly agriculture. This paper reviews the underlying mechanisms that are confidently linked with plant–AMF interaction in alleviating drought stress, constructing emphasis on phytohormones and signaling molecules and their interaction with biochemical, and physiological processes to maintain the homeostasis of nutrient and water cycling and plant growth performance. Likewise, the paper will analyze how the AMF symbiosis helps the plant to overcome the deleterious effects of stress is also evaluated. Finally, we review how interactions between various signaling mechanisms governed by AMF symbiosis modulate different physiological responses to improve drought tolerance. Understanding the AMF-mediated mechanisms that are important for regulating the establishment of the mycorrhizal association and the plant protective responses towards unfavorable conditions will open new approaches to exploit AMF as a bioprotective tool against drought. [ABSTRACT FROM AUTHOR]

Background: Magnaporthe oryzae, the causal fungus of rice blast disease, negatively impacts global rice production. Wild rice (Oryza rufipogon), a relative of cultivated rice (O. sativa), possesses unique attributes that enable it to resist pathogen invasion. Although wild rice represents a major resource for disease resistance, relative to current cultivated rice varieties, no prior studies have compared the immune and transcriptional responses in the roots of wild and cultivated rice to M. oryzae.Results: In this study, we showed that M. oryzae could act as a typical root-infecting pathogen in rice, in addition to its common infection of leaves, and wild rice roots were more resistant to M. oryzae than cultivated rice roots. Next, we compared the differential responses of wild and cultivated rice roots to M. oryzae using RNA-sequencing (RNA-seq) to unravel the molecular mechanisms underlying the enhanced resistance of the wild rice roots. Results indicated that both common and genotype-specific mechanisms exist in both wild and cultivated rice that are associated with resistance to M. oryzae. In wild rice, resistance mechanisms were associated with lipid metabolism, WRKY transcription factors, chitinase activities, jasmonic acid, ethylene, lignin, and phenylpropanoid and diterpenoid metabolism; while the pathogen responses in cultivated rice were mainly associated with phenylpropanoid, flavone and wax metabolism. Although modulations in primary metabolism and phenylpropanoid synthesis were common to both cultivated and wild rice, the modulation of secondary metabolism related to phenylpropanoid synthesis was associated with lignin synthesis in wild rice and flavone synthesis in cultivated rice. Interestingly, while the expression of fatty acid and starch metabolism-related genes was altered in both wild and cultivated rice in response to the pathogen, changes in lipid acid synthesis and lipid acid degradation were dominant in cultivated and wild rice, respectively.Conclusions: The response mechanisms to M. oryzae were more complex in wild rice than what was observed in cultivated rice. Therefore, this study may have practical implications for controlling M. oryzae in rice plantings and will provide useful information for incorporating and assessing disease resistance to M. oryzae in rice breeding programs. [ABSTRACT FROM AUTHOR]

Highlights • Farm manure can increase soil enzymatic activities. • Farm manure can enhance the rhizospheric bacterial abundance and Shannon index. • Bacterial communities correlated with environmental factors and enzymatic activities. • Incorporation of organic manure can improve saline-alkaline soils fertility. Abstract Soil salinization is one of the key factors that threatens plant existence worldwide and is a major challenge to sustain crop production and soil quality. However, there has been limited research on the responses of microbial communities and enzyme activities under soil amendments application in saline alkaline soils. Here, we explored the response of microbial communities and enzyme activities to soil amendments based on 7-year field experiment. The five treatments included FA, amended with farm manure; DE, amended with desulfurization gypsum; SA, amended with sandy soil; M, amended with a mixture of FA, DE and SA; and CK, non-amended control. Relative to the CK treatment, the four amendments, particularly FA, DE and M, significantly decreased the soil pH. Enzyme activities (catalase, urease, alkaline phosphatase and cellulase) were increased in the FA, DE and M treatments, while no difference was observed between SA and CK, except in cellulase. A total of 439,575 effective sequences after filtering out of 1,017,148 raw reads were obtained resulting in 9096 OTUs. Six bacterial phyla of the highest relative abundance were detected including Proteobacteria , Chloroflexi , Bacteroidetes , Actinobacteria , Acidobacteria and Firmicutes across all soil samples (accounting for >85% of the reads). The bacterial community richness was increased in the FA, DE and M treatments, whereas it showed a similar pattern between the CK and SA treatments. Bacterial community diversity was remarkably higher in the M, FA and DE treatments compared to that of CK, while it was reduced in SA. There was a higher similarity in the bacterial communities among DE, FA and M, as well as between CK and SA. Our findings showed that organic manure is a better application approach for the restoration of saline-alkaline soil based on improving the bacterial community and enzyme activities. [ABSTRACT FROM AUTHOR]

Abstract The rhizomicrobiome plays a key role in suppressing soil-borne plant diseases. It remains unclear if crop domestication has altered the rhizomicrobiome and reduced the resistance of domesticated crops to pathogens. To investigate this question, the pathogenic fungus Magnaporthe oryzae was administered to the rhizosphere of plants of cultivated and wild rice to compare the impact of the fungal pathogen on their rhizomicrobiome. The analysis of the results indicated that the presence of M. oryzae affected the community structure and diversity of the rhizomicrobiome of both cultivated and wild rice species. Bacterial and fungal α- and β-diversity of the rhizosphere of cultivated rice were altered more significantly than in wild rice. Furthermore, the abundance of the introduced pathogen was significantly lower in the rhizosphere of wild rice, while the relative abundance of putatively beneficial bacterial and fungal taxa was higher, relative to cultivated rice. These results suggest that the rhizomicrobiome of cultivated rice was more sensitive to the introduction of the fungal pathogen and more easily disturbed than the rhizosphere community of its wild relative. Additionally, a correlation analysis of microbiome and root transcriptome data, obtained under pathogenic and non-pathogenic conditions, indicated that fungal members of the Glomeromycota are important for promoting phenylpropanoid and lignin syntheses in wild rice, which plays a role in resisting M. oryzae infection. The identified differences between the responses of the rhizomicrobiomes of cultivated and wild rice to M. oryzae may provide information that can be used in developing novel strategies to control soil-borne pathogens, which include reconstructing the rhizomicrobiome of domesticated crops to be similar to their wild relatives. Highlights • Rhizomicrobiomes of both cultivated and wild rice are affected by the pathogen Magnaporthe oryzae. • Rhizomicrobiome of cultivated rice is more sensitive to M. oryzae than that of wild rice. • Glomeromycota fungi might play an important role in the resistance of wild rice to M. oryzae. [ABSTRACT FROM AUTHOR]

The plants and root-associated microbiomes are closely related. Plant metabolic substances can serve as a nutrient source for the microbiome, and in return, the microbiome can regulate the production of plant metabolic substances. Wild rice ( Oryza rufipogon ), as the ancestor of cultivated rice ( Oryza sativa ), has changed several metabolic pathways and root-associated microbiome during evolution. Thus, the study of the different associations between metabolic pathways and root-associated microbiomes in wild and cultivated rice varieties is important for rice breeding. In this article, the co-evolutionary association between metabolic pathways, which are based on transcriptome data, and root-associated microbiomes, which are based on 16S rRNA and internal transcribed spacer (ITS) amplicon data, in wild and cultivated rice was studied. The results showed that the enriched pathways were differentially correlated with the enriched microbiomes in wild and cultivated rice varieties. Pathways for ‘Glutathione metabolism’, ‘Plant-pathogen interaction’, ‘Protein processing in endoplasmic reticulum’ and ‘Tyrosine metabolism’ were positively associated with the improved relative abundance of bacterial and fungal operational taxonomic units (OTUs) in wild rice. On the other hand, ‘Glycolysis/Gluconeogenesis’, ‘Brassinosteroid biosynthesis’, ‘Carbon metabolism’, ‘Phenylpropanoid biosynthesis’ and ‘Caffeine metabolism’ were positively correlated with the improved relative abundance of bacterial and fungal OTUs in cultivated rice. Redundancy analysis showed that certain bacterial and fungal species could positively and significantly affect plant gene expression; for instance, Streptomyces , with 8.7% relative abundance in bacterial community, significantly affected plant gene expression in wild rice. This study can provide the theoretical basis for recognizing the associations between root-associated microbiomes and root transcriptomes in wild and cultivated rice varieties, and can provide practical significance for developing useful bacterial and fungal resources in wild rice. [ABSTRACT FROM AUTHOR]

Background: over the last two decades, only few dermatology research papers have been published in Saudi Arabia provided the small number of experts -in this field -enlisted in higher education institutions. Hence a compelling need to review the recent publications and define the current prevalence, status and interventions needed. Objective: To present an overview of the common dermatological diseases, particularly eczema and dermatitis, in Saudi community as well as their effects and ways to mitigate them. Methods: Review of Randomized Controlled Trials (RCTs) researches conducted and published in Saudi Arabia. Results: Empirical findings revealed that Acne, Eczema and Psoriasis are the most common dermatological disorders among the Saudi community while Atopic Dermatitis was the most common mostly affecting children. In the meantime, Vitiligo emerged to be the most rampant pigmentary ailment, also viral warts appeared predominant covering up to 12% of the patients in the subject. On the other hand, dermatophytoses occurred commonly among the fungal conditions, while psoriasis arose as the most recurrent papulosquamous condition. Conclusion: The prevalence of dermatological disorders in Saudi Arabia is rather high with the issue being overlooked and deprioritized in favor of graver pathological conditions despite the significant social, psychological and quality of life impact on the patients. Thus, we recommended that proper education and awareness campaigns on skin diseases should be provided at all academic and social levels as one way of prevention and alleviation of skin diseased in Saudi Arabia. [ABSTRACT FROM AUTHOR]

[Display omitted] • The bacterial variation within microhabitats associated with the black stone of the Black Gobi desert were investigated. • Bacterial communities within microhabitats were highly different in the desert ecosystems. • Microhabitats formed by black stones support highly diverse and biologically active bacterial communities. • Major environmental controls were water content, total carbon, and total nitrogen. Desert soil around the black stones is highly complex, which substantially affects the diversity and composition of inhabiting microbes. The existence of black stones in the southern part of the Black Gobi desert of China could provide microhabitats for diverse bacterial communities that remain unexplored. Hence, Illumina MiSeq sequencing was used to determine the differences in bacterial communities associated within microhabitats in three sites of the Black Gobi desert, China. Our results show that bacterial communities are significantly affected by each microhabitat. For instance, the α -diversity of bacterial communities indicated more remarkable diversity and richness in these microhabitats. Considering β -diversity, variances were reported mainly in the Proteobacteria (30%), Actinobacteria (26%), Chloroflexi (19%), and Firmicutes (9%). Firmicutes were markedly enriched in the upper surface, especially in site 1. Compared to other microhabitats, the relative abundance of Proteobacteria was greater in the subsurface, and they were also more dominant in the other two sites. Network analysis of soil factors and bacterial genera showed that the most significant-occurrences were positively correlated, demonstrating potential synergistic interactions. Collective with the predicted function profiles and the redundancy analysis, these results indicated the highest variances in bacterial community structure and function in Black Gobi Desert ecosystems. These differences are likely closely related to the soil parameters, mainly water content, total carbon, and total nitrogen, and might be associated with black stones. This study concludes that microhabitats formed by black stones support highly diverse and biologically active bacterial communities. These microhabitats with extreme environmental conditions deliver new opportunities to explore soil bacterial communities at relevant spatial scales in the Black Gobi desert. [ABSTRACT FROM AUTHOR]