Integrative multi-omics analysis reveals the crucial biological pathways involved in the adaptive response to NaCl stress in peanut seedlings.

Plant growth is restricted by salt stress, which is a significant abiotic factor, particularly during the seedling stage. The aim of this study was to investigate the mechanisms underlying peanut adaptation to salt stress by transcriptomic and metabolomic analysis during the seedling stage. In this study, phenotypic variations of FH23 and NH5, two peanut varieties with contrasting tolerance to salt, changed obviously, with the strongest differences observed at 24 h. FH23 leaves wilted and the membrane system was seriously damaged. A total of 1470 metabolites were identified, with flavonoids being the most common (21.22%). Multi-omics analyses demonstrated that flavonoid biosynthesis (ko00941), isoflavones biosynthesis (ko00943), and plant hormone signal transduction (ko04075) were key metabolic pathways. The comparison of metabolites in isoflavone biosynthesis pathways of peanut varieties with different salt tolerant levels demonstrated that the accumulation of naringenin and formononetin may be the key metabolite leading to their different tolerance. Using our transcriptomic data, we identified three possible reasons for the difference in salt tolerance between the two varieties: (1) differential expression of LOC112715558 (HIDH) and LOC112709716 (HCT), (2) differential expression of LOC112719763 (PYR/PYL) and LOC112764051 (ABF) in the abscisic acid (ABA) signal transduction pathway, then (3) differential expression of genes encoding JAZ proteins (LOC112696383 and LOC112790545). Key metabolites and candidate genes related to improving the salt tolerance in peanuts were screened to promote the study of the responses of peanuts to NaCl stress and guide their genetic improvement.

Designing a slippery/superaerophobic hierarchical open channel for reliable and versatile underwater gas delivery.

Achieving long-term and stable gas manipulation in an aqueous environment is necessary to improve multiphase systems relating to gas/liquid interaction. Inspired by the Pitcher plant and the hummingbird beak, we report a slippery/superaerophobic (SLSO) hierarchical fluid channel for continuous, durable, and flexible gas transport. The immiscible lubricant layer inside the SLSO channel promotes one-year stability of gas transport, and the maximum flux of this open channel can reach 3000 mL h-1. Further integration of a CO2 capturing microchip demonstrates the availability and potential of this gas-manipulating interface, which should provide a valuable platform to develop advanced materials and devices.

Optimizing Living Material Delivery During the COVID-19 Outbreak.

The coronavirus disease 2019 (COVID-19) epidemic has spread worldwide, posing a great threat to human beings. The stay-home quarantine is an effective way to reduce physical contacts and the associated COVID-19 transmission risk, which requires the support of efficient living materials (such as meats, vegetables, grain, and oil) delivery. Notably, the presence of potential infected individuals increases the COVID-19 transmission risk during the delivery. The deliveryman may be the medium through which the virus spreads among urban residents. However, traditional delivery route optimization methods don't take the virus transmission risk into account. Here, we propose a novel living material delivery route approach considering the possible COVID-19 transmission during the delivery. A complex network-based virus transmission model is developed to simulate the possible COVID-19 infection between urban residents and the deliverymen. A bi-objective model considering the COVID-19 transmission risk and the total route length is proposed and solved by the hybrid meta-heuristics integrating the adaptive large neighborhood search and simulated annealing. The experiment was conducted in Wuhan, China to assess the performance of the proposed approach. The results demonstrate that 935 vehicles will totally travel 56,424.55 km to deliver necessary living materials to 3,154 neighborhoods, with total risk [Formula: see text]. The presented approach reduces the risk of COVID-19 transmission by 67.55% compared to traditional distance-based optimization methods. The presented approach can facilitate a well response to the COVID-19 in the transportation sector.

Response of carbon, nitrogen and phosphorus concentration and stoichiometry of plants and soils during a soybean growth season to O3 stress and straw return in Northeast China.

Carbon (C), nitrogen (N) and phosphorus (P) concentrations and stoichiometry play important roles in biogeochemical cycles of the ecosystems, yet it is still unclear how the allocations of C, N and P concentrations and stoichiometry among plant organs and soils related to O3 stress and straw return. Here, a pot experiment was conducted in open top chambers to monitor the response of C, N and P concentrations and stoichiometry of leaves, stems, roots and soils during a growing season (branching, flowering and podding stages) of soybean (Glycine max; a species highly sensitive to O3) to background O3 concentration (44.8 ± 5.6 ppb), O3 stress (79.7 ± 5.4 ppb) and straw treatment (no straw return and straw return). O3 stress significantly decreased root biomass. Straw return significantly increased root biomass under O3 stress at branching and flowering stages. Generally, O3 stress and straw return showed significant effects on the C, N and P concentrations of leaves and soils, and stoichiometric ratios of leaves, stems and microbial biomass. The C, N and P concentrations and stoichiometry of leaves, stems, roots and soils in response to O3 stress and straw return at the branching stage were inconsistent with the changes observed at the flowering and podding stages. The P conversion efficiency showed significant relationship with root P concentration under the combined effects of O3 stress and straw return. Altogether, the present study indicated that C, N and P concentrations of soybean might be more important than stoichiometric ratios as a driver of root defence against O3 stress in the case of straw return.

Interannual variability in net ecosystem carbon production in a rain-fed maize ecosystem and its climatic and biotic controls during 2005-2018.

Interannual variability (IAV) in net ecosystem carbon production (NEP) plays an important role in the processes of the carbon cycle, but the long-term trends in NEP and the climatic and biotic control of IAV in NEP still remain unclear in agroecosystems. We investigated interannual variability in NEP, expressed as annual values and anomalies, and its climatic and biotic controls using an eddy-covariance dataset for 2005-2018 for rain-fed spring maize in northeastern China. Average annual NEP was 270±31 g C m-2yr -1, with no significant changes over time. The effects on interannual variability in NEP of gross ecosystem productivity (GEP) that was mainly controlled by soil water content (SWC) and leaf area index (LAI), were more than those of respiration (RE) that was controlled by temperature and LAI. Further, maximum daily NEP (NEPmax) that was dominated by summer vapor pressure deficit explained the largest fraction of annual anomalies in NEP, followed by carbon dioxide uptake period (CUP) that was defined by the beginning date (BDOY) and the end date (EDOY) of CUP. The variability in BDOY was mainly determined by spring precipitation and the effective accumulated temperature, and the variability in EDOY was determined by autumn precipitation, SWC and LAI. NEP may decrease with declining precipitation in the future due to decreasing GEP, NEPmax, or CUP, and irrigation and residues cover may be useful in efforts to maintain current NEP levels. Our results indicate that interannual variability in NEP in agroecosystems may be more sensitive to changes in water conditions (such as precipitation, SWC and VPD) induced by climate changes, while temperature may be an important indirect factor when VPD is dominated.

The Smaller the Leaf Is, the Faster the Leaf Water Loses in a Temperate Forest.

Leaf size (i.e., leaf surface area and leaf dry mass) profoundly affects a variety of biological carbon, water and energy processes. Therefore, the remarkable variability in individual leaf size and its trade-off with total leaf number in a plant have particularly important implications for understanding the adaption strategy of plants to environmental changes. The various leaf sizes of plants growing in the same habitat are expected to have distinct abilities of thermal regulation influencing leaf water loss and shedding heat. Here, we sampled 16 tree species co-occurring in a temperate forest in northeastern China to quantify the variation of leaf, stomata and twigs traits, and to determine the relationships of leaf size with leaf number and leaf water loss. We examined the right-skewed distributions of leaf size, leafing intensity, stomatal size and stomatal density across species. Leafing intensity was significantly negatively correlated with leaf size, accounting for 4 and 12% of variation in leaf area and leaf mass, respectively. Species was the most important factor in explaining the variation in leaf size (conditional R 2 of 0.92 for leaf area and 0.82 for leaf mass). Leaf area and mass significantly increased with increasing diameter of twigs. Leaf water loss was strongly negatively correlated with leaf area and leaf mass during the first four hours of the measurement. Leaf area and leaf mass accounted for 38 and 30% of variation in total leaf water loss, respectively. Leaf water loss rate (k) was significantly different among tree species and markedly linearly decreased with increasing leaf area and leaf mass for simple-leaved tree species. In conclusion, the existence of a cross-species trade-off between the size of individual leaves and the number of leaves per yearly twig unit was confirmed in that temperate forest. There was strongly negative correlation between leaf water loss and leaf size across tree species, which provides evidences for leaf size in leaf temperature regulation in dry environment with strong radiation. The size-dependent leaf water relation is of central importance to recognize the functional role of leaf size in a changing climate including rapid changes in air temperature and rainfall.

Assessing the regional carbon sink with its forming processes- a case study of Liaoning province, China.

Assessing the regional carbon sink sets the basis of regional carbon management, which involves many measures but has large uncertainties. Carbon sink assessment scheme based on its forming processes (CSF) is a recently proposed measure but repeatly calculates emission from water erosion and ignored human inducing carbon inputs. Therefore, we revised the CSF by calculating the direct outputs from land surface and adding human returned carbon (HC) to the input. The revised CSF thus involved gross primary productivity (GPP), ecosystem respiration (ER), carbon removal from cropland (CRC), emission from reactive carbon (ERC), emission from water erosion (Ewat), and HC, which can be obtained from public data sources. Then the revised CSF was applied to the Liaoning province of China. The estimated carbon input of Liaoning province during 2000-2014 was 114.77 ± 8.41 TgC yr-1, while the carbon output was 110.48 ± 8.38 TgC yr-1. The difference between input and output induced a carbon sink of 4.30 ± 2.20 TgC yr-1, accounting for 3.75% of total carbon input. The carbon sink spatially decreased from northeast to southwest, which was highly correlated with that of GPP. However, though its forming fluxes significantly increased from 2000 to 2014, the carbon sink showed a decreasing trend. In addition, the revised scheme only needed published and public data, which made it serve as an alternative approach for regional carbon budget assessment.

Six-Year Nitrogen-Water Interaction Shifts the Frequency Distribution and Size Inequality of the First-Order Roots of Fraxinus mandschurica in a Mixed Mature Pinus koraiensis Forest.

The variation in fine root traits in terms of size inequality at the individual root level can be identified as a strategy for adapting to the drastic changes in soil water and nutrient availabilities. The Gini and Lorenz asymmetry coefficients have been applied to describe the overall degree of size inequality, which, however, are neglected when conventional statistical means are calculated. Here, we used the Gini coefficient, Lorenz asymmetry coefficient and statistical mean in an investigation of Fraxinus mandschurica roots in a mixed mature Pinus koraiensis forest on Changbai Mountain, China. We analyzed 967 individual roots to determine the responses of length, diameter and area of the first-order roots and of branching intensity to 6 years of nitrogen addition (N), rainfall reduction (W) and their combination (NW). We found that first-order roots had a significantly greater average length and area but had smaller Gini coefficients in NW plots compared to in control plots (CK). Furthermore, the relationship between first-order root length and branching intensity was negative in CK, N, and W plots but positive in NW plots. The Lorenz asymmetry coefficient was >1 for the first-order root diameter in NW and W plots as well as for branching intensity in N plots. The bimodal frequency distribution of the first-order root length in NW plots differed clearly from the unimodal one in CK, N, and W plots. These results demonstrate that not only the mean but also the variation and the distribution mode of the first-order roots of F. mandschurica respond to soil nitrogen and water availability. The changes in size inequality of the first-order root traits suggest that Gini and Lorenz asymmetry coefficients can serve as informative parameters in ecological investigations of roots to improve our ability to predict how trees will respond to a changing climate at the individual root level.

Divergent drivers of the spatial and temporal variations of cropland carbon transfer in Liaoning province, China.

Spatial and temporal variations are important points of focus in ecological research. Analysing their differences improves our understanding on the variations of ecological phenomena. Using data from the Liaoning Statistical Yearbook, we investigated the spatial and temporal variations of cropland carbon transfer (CCT), an important ecological phenomenon in quantifying the regional carbon budget, in particular, the influencing factors and difference. The results showed that, from 1992 to 2014, the average CCT in Liaoning province was 18.56 TgC yr-1 and decreased from northwest to southeast. CCT spatial variation was primarily affected by the ratio of planting area to regional area (RPR) via its effect on the magnitude of carbon transfer (MCT), which depended mainly on fertilizer usage per area (FUA). From 1992 to 2014, CCT exhibited a significantly increasing trend with a rate of 0.48 TgC yr-1. The inter-annual variation of CCT was dominated by carbon transfer per planting area (CTP) through its effect on MCT, which significantly correlated with FUA but showed no significant correlation with climatic factors. Therefore, the factors affecting the spatial variation of CCT differed from those that affected its inter-annual variation, indicating that the spatial and temporal variations of ecological phenomena were affected by divergent factors.

Combined Effects of Elevated O3 Concentrations and Enhanced UV-B Radiation of the Biometric and Biochemical Properties of Soybean Roots.

Enhanced ultraviolet-B (UV-B) radiation and elevated tropospheric ozone alone may inhibit the growth of agricultural crops. However, research regarding their combined effects on growth and biochemical properties of roots is still scarce. Using open top chambers, we monitored the response of growth, secondary metabolites, endogenous hormones and enzyme activities of soybean roots to elevated O3 and enhanced UV-B individually and in combination at stages of branching, flowering and podding. Our results indicated that the root biomass decreased by 23.6, 25.2, and 27.7%, and root oxidative capacity declined by11.2, 39.9, and 55.7% exposed to elevated O3, enhanced UV-B, and O3 + UV-B, respectively, compared to the control treatment. Concentrations of quercetin and ABA were significantly increased, while concentrations of total polyphenol and P-coumaric acid responded insignificantly to elevated O3, enhanced UV-B, and O3 + UV-B during the whole period of soybean growth. Elevated O3, enhanced UV-B and O3 + UV-B showed significant negative effects on superoxide dismutase (EC 1.15.1.1) activity at flowering stage, on activities of peroxidase (EC 1.11.1.7) and catalase (EC 1.11.1.6) at podding stage, on ascorbate peroxidase activity during the whole period of soybean growth. Moreover, compared to hormones and enzyme activity, secondary metabolisms showed stronger correlation with root growth exposed to elevated O3 and enhanced UV-B individually and in combination. Our study concluded that combined effects of O3 and UV-B radiation significantly exacerbated the decline of soybean root growth, and for annual legumes, the inhibited root growth exposed to O3 and/or UV-B radiation was mostly associated with secondary metabolisms (especially flavonoids).

Combined effects of O3 and UV radiation on secondary metabolites and endogenous hormones of soybean leaves.

Enhanced ultraviolet radiation (UV) and elevated tropospheric ozone (O3) may individually cause reductions in the growth and productivity of important agricultural crops. However, research regarding their combined effects on important agricultural crops is still scarce, especially on changes in secondary metabolites and endogenous hormones, which are important protective substances and signal components that control plant responses to environment stresses. In this study, using an experimental setup of open top chambers, we monitored the responses of seed yield per plant, leaf secondary metabolites and leaf endogenous hormones under the stress of elevated O3 and enhanced UV radiation individually, as well as their combined stress. The results indicated that elevated O3 (110 ± 10 nmol mol-1 for 8 hours per day) and enhanced UV radiation (1.73 kJ h-1 m-2) significantly decreased seed yield per plant. Concentrations of rutin, queretin and total flavonoids were significantly increased under the elevated O3 treatment or the enhanced UV radiation treatment or the combination treatment at flowering and podding stages, and concentrations of rutin, queretin and total flavonoids showed significant correlations with seed yield per plant. Concentrations of ABA and IAA decreased under the three treatments. There was a significant positive correlation between the ABA concentration and seed yield and a negative correlation between the IAA concentration and seed yield. We concluded that the combined stress of elevated O3 and UV radiation significantly decreased seed yield per plant. Yield reduction was associated with changes in the concentrations of flavonoids, ABA and IAA in soybean leaves. The effects of the combined O3 and UV stress were always greater than those of the individual stresses alone.

Global Transcriptomic Profiling of Cortex and Striatum: Cerebral Injury after Ischemia/Reperfusion in a Mouse Model.

OBJECTIVE: This study aims to investigate the molecular mechanism of injury development in the cortex and the striatum after cerebral ischemia/reperfusion (I/R). METHODS: Gene expression data (GSE23160) in the cortex and the striatum of an intraluminal middle cerebral artery occlusion-I/R mouse model (N = 12) and sham controls (N = 4) were downloaded from the Gene Expression Omnibus. Limma package was used to identify the differentially expressed genes (DEGs) between the I/R (2, 8, and 24 hours) and control groups. Correlation analysis was then performed to identify the highly correlated differentially expressed genes (HCDEGs). STRING and Cytoscape software were used to construct a protein-protein interaction (PPI) network of HCDEGs. Furthermore, Venny 2.0 was used to identify common overlapped DEGs whose transcription factors (TFs) were predicted using iRegulon in Cytoscape. RESULTS: For the cortex and the striatum, 2295 and 2282 DEGs were respectively identified between the I/R group and the controls, and were classified into 3 and 2 correlation modules. For each module, a PPI network was constructed, and Toll-like receptor 2 (Tlr2, degree = 25), interleukin 1ß (Il1b, degree = 21), and heme oxygenase-1 (Hmox1, degree = 17) had high connective degrees. Furthermore, 29 common overlapped DEGs were found across time and tissue, which might be targeted by 13 TFs. Especially, Tlr2, Il1b, and Hmox1 were targeted by myeloblastosis protein (Myb, target count = 16) and FBJ osteosarcoma protein (Fos, target count = 15). Moreover, plasminogen activator urokinase receptor (Plaur) was targeted by Fos, and it was an HCDEG in correlation modules of both cortex and striatum. Upregulation of Tlr2, Il1b, Hmox1, and Plaur in I/R injury was confirmed using quantitative polymerase chain reaction and immunohistochemical staining. CONCLUSION: Tlr2, Il1b, Hmox1, and Plaur regulated by Myb and Fos might participate in cortex and striatum injury after cerebral I/R.

Interactive effects of elevated ozone and UV-B radiation on soil nematode diversity.

Ultraviolet-B (UV-B) radiation and elevated tropospheric ozone may cause reductions in the productivity and quality of important agricultural crops. However, research regarding their interactive effect is still scarce, especially on the belowground processes. Using the open top chambers experimental setup, we monitored the response of soil nematodes to the elevated O3 and UV-B radiation individually as well as in combination. Our results indicated that elevated O3 and UV-B radiation have impact not only on the belowground biomass of plants, but also on the community structure and functional diversity of soil nematodes. The canonical correspondence analysis suggested that soil pH, shoot biomass and microbial biomass C and N were relevant parameters that influencing soil nematode distribution. The interactive effects of elevated O3 and UV-B radiation was only observed on the abundance of bacterivores. UV-B radiation significantly increased the abundance of total nematodes and bacterivores in comparison with the control at pod-filling stage of soybean. Following elevated O3, nematode diversity index decreased and dominance index increased relative to the control at pod-filling stage of soybean. Nematode functional diversity showed response to the effects of elevated O3 and UV-B radiation at pod-bearing stage. Higher enrichment index and lower structure index in the treatment with both elevated O3 and UV-B radiation indicated a stressed soil condition and degraded soil food web. However, the ratios of nematode trophic groups suggested that the negative effects of elevated O3 on soil food web may be weakened by the UV-B radiations.

[Effects of elevated O3 concentration and UV-B radiation on the chlorophyll content and active oxygen metabolism of soybean leaves].

Taking the soybean (Glycine max) cultivar Tiefeng 29 as test material, and by using open-top chamber, this paper studied the effects of elevated O3 concentration and UV-B radiation on the leaf chlorophyll content, lipid peroxidation, reactive oxygen species (ROS) production rate, anti-oxidation enzymes activities, and the grain yield. During the growth period of soybean, as compared with the control, the leaf Chl a, Chl b and Chl (a+b) contents under the stresses of O3 and UV-B had a decreasing trend, the relative electrical conductivity, malondialdehyde content, superoxide anion (O2) production rate, and hydrogen peroxide (H2O2) content increased, and the activities of superoxide dismutase, peroxidase and catalase as well as the grain yield decreased. O3+ UV stress aggravated the leaf membrane lipid peroxidation, promoted the ROS production, and decreased the plant antioxidant capacity and leaf chlorophyll content. The negative effects of O3 stress on soybean leaves were more close to the impacts of O3+UV stress, suggesting that O3 might play an important role in the combined stress.

Effects of elevated O3 and/or elevated CO2 on lipid peroxidation and antioxidant systems in Ginkgo biloba leaves.

Four-year-old seedlings of Ginkgo biloba were exposed to elevated O(3), elevated CO(2) and elevated O(3) plus elevated CO(2) in open-top chambers (OTCs) to study the responses of antioxidant system in Ginkgo biloba leaves. No significant changes in reactive oxygen production and scavenging systems were detected in seedlings exposed to high CO(2). Significant increase in H(2)O(2) and MDA content were induced by elevated O(3). The ascorbate content and antioxidative enzymes activity were increased significantly by exposure to high O(3) as well. But the promoted ability in scavenging did not prevent the increase in H(2)O(2) content and cell membrane lipid peroxidation. The increase was mitigated by high CO(2) in the combined exposure, but the effect was hardly significant.

Respective and interactive effects of doubled CO2 and O3 concentration on membrane lipid peroxidation and antioxidative ability of soybean.

Effects of doubled CO2 and O3 concentration on Soybean were studied in open-top chambers (OTC). Under doubled CO2 concentration, grain yield and biomass increased, the SOD activity, vitamin C (Vc) and carotenoid (Car) content also increased; Superoxide (O2-*) generating rate decreased, relative conductivity and malondialdehyde (MDA) content significantly declined. But under doubled O3 concentration, the SOD activity, Vc and Car contents declined, resulting in imbalance of activated-oxygen production, enhanced O2-* generating rate and accelerated process of lipid peroxidation and increase in MDA content and ion leakage of leaves. The final result was decreased grain yield and plant biomass. Interactive effects of doubled CO2 and O3 concentrations on soybean were mostly counteractive. However, the beneficial effects of concentration-doubled CO2 more than compensate the negative effects imposed by doubled O3, and the latter in its turn partly counteracted the positive effects of the former.

[Effect of doubled CO2 and O3 concentration and their interactions on ultrastructure of soybean chloroplast].

The effect of doubled CO2 and O3 concentration on the ultrastructure of chloroplast in leaf cells of soybean was tested by open-top chamber method, and examined under transmission electron microscope. The results showed that under doubled CO2 concentration, the amount and volume of starch grains in chloroplast increased, but the chloroplast membrane and the lamellar structure still kept integrated. The accumulation of starch grains was restrained, and the chloroplast membrane and the lamellar structure were disorganized under doubled-O3 concentration. The ultrastructure of chloroplast was destroyed in different degrees under the interaction of doubled CO2 and O3 concentration. The damage to chloroplast arose from the abrupt doubling of CO2 and O3 was more severe than that from gradual increase of CO2 and O3 concentration. The negative effect of O3 was partly compensated by the positive effect of doubled CO2.