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The Nile tilapia, Oreochromis niloticus, GIFT strain is suggested to be a good candidate for culture in brackish water. Gill is regarded as the dominate site of osmo-regulation. Recently, the mechanisms underlying salinity challenge in gill of tilapia are getting increasing attention. In this study, an integrated analysis of metabolomics and transcriptomics on gill of GIFT tilapia under salinity 17 and 27 challenge for three and a half months are conducted. 1164 DEGs in the comparison 0 vs 17 and 910 DEGs in the comparison 0 vs 27 are identified. Many typical genes involved in osmo-regulation are found, including calcium/calmodulin-dependent protein kinase II beta 1, Aquaporin 3, Potassium channel subfamily K member, chloride channel 2, Solute Carrier Family 12 Member 8, Solute Carrier Family 12 Member 2, Na +/K + ATPase. Some biosynthesis, metabolism, energy or transport related pathways are over-represented, such as Synthesis of UDP-N-acetyl-glucosamine, Synthesis of substrates in N-glycan biosynthesis, Biosynthesis of DPAn-3 SPMs, Metabolism of lipids, Gluconeogenesis and SLC-mediated transmembrane transport. In addition, totally 23 metabolites are significantly responded in gill under salinity challenge. Of which, 11 metabolites including 12-Hydroxyeicosatetraenoic acid and choline are significantly down-regulated and 8 metabolites including adenine, Lys-Pro, inosine are significantly up-regulated under salinity challenge. Our study provides an important database for further functional analysis of osmo-regulation in gill of Nile tilapia.

Tea (Camellia sinensis) is the most popular nonalcoholic beverage worldwide. During cultivation, tea plants are susceptible to herbivores and pathogens, which can seriously affect tea yield and quality. A previous report showed that (Z)-3-hexenol is a potentially efficient defensive substance. However, the molecular mechanism mediating (Z)-3-hexenol signaling in tea plants and the resulting effects on plant defenses remain uncharacterized. To clarify the signaling mechanisms in which (Z)-3-hexenol and light are involved, the gene transcription and metabolite levels were assessed, respectively. This study demonstrated that tea plants rapidly and continuously release (Z)-3-hexen-1-ol in response to an insect infestation. (Z)-3-Hexen-1-ol absorbed by adjacent healthy plants would be converted into three insect defensive compounds: (Z)-3-hexenyl-glucoside, (Z)-3-hexenyl-primeveroside, and (Z)-3-hexenyl-vicianoside identified with laboratory-synthesized standards. Moreover, (Z)-3-hexen-1-ol also activates the synthesis of jasmonic acid to enhance the insect resistance of tea plants. Additionally, a continuous light treatment induces the accumulation of (Z)-3-hexenyl-glycosides. Hence, (Z)-3-hexenol serves as a light-regulated signaling molecule that activates the systemic defenses of adjacent plants. Our study reveals the molecular mechanisms by which biotic and abiotic factors synergistically regulate the signaling functions of herbivore-induced plant volatiles in plants, providing valuable information for future comprehensive analyses of the systemic defense mechanisms in plants.

Herbivore-induced plant volatiles (HIPVs) play an important role in insect resistance. As a common HIPV in tea plants (Camellia sinensis), β-ocimene has shown anti-insect function in other plants. However, whether β-ocimene in tea plants also provides insect resistance, and its mechanism of synthesis and emission are unknown. In this study, β-ocimene was confirmed to interfere with tea geometrid growth via signaling. Light was identified as the key factor controlling regular emission of β-ocimene induced by the wounding from tea geometrids. β-Ocimene synthase (CsBOS1) was located in plastids and catalyzed β-ocimene formation in overexpressed tobacco. CsBOS1 expression in tea leaves attacked by tea geometrids showed a day-low and night-high variation pattern, while CsABCG expression involved in volatile emission showed the opposite pattern. These two genes might regulate the regular β-ocimene emission from tea plants induced by tea geometrid attack. This study advances the understanding on HIPV emission and signaling in tea plants.

Some members of the CYP51G subfamily has been shown to be obtusifoliol 14α-demethylase, key enzyme of the sterol and brassinosteroid (BR) biosynthesis, which mediate plant development and response to stresses. However, little is known about the functions of CYP51H subfamily in rice. Here, OsCYP51H3, an ortholog of rice OsCYP51G1 was identified. Compared with wild type, the mutants oscyp51H3 and OsCYP51H3-RNAi showed dwarf phenotype, late flowering, erected leaves, lower seed-setting rate, and smaller and shorter seeds. In contrast, the phenotypic changes of OsCYP51H3-OE plants are not obvious. Metabolomic analysis of oscyp51H3 mutant indicated that OsCYP51H3 may also encode an obtusifoliol 14α-demethylase involved in phytosterol and BR biosynthesis, but possibly not that of triterpenes. The RNA-seq results showed that OsCYP51H3 may affect the expression of a lot of genes related to rice development. These findings showed that OsCYP51H3 codes for a putative obtusifoliol 14α-demethylase involved in phytosterol and BR biosynthesis, and mediates rice development.

Phytoliths are microscopic particles of amorphous silica produced by plants that have vital importance for environmental change and carbon sequestration. This study investigated phytoliths and their morphotype assemblages, and phytolith-occluded carbon (PhytOC) along a marsh degradation gradient to clarify the significance of phytoliths for evaluating carbon sequestration dynamics during marsh degradation on the Zoige Plateau, China. Soil samples from non-degraded marsh (NDM), lightly degraded marsh (LDM), moderately degraded marsh (MDM), and seriously degraded marsh (SDM) were collected. Soil phytolith shape and PhytOC were determined using heavy liquid suspension, microscope observations, and alkali-solution spectrophotometry. The dominant phytolith morphotypes among the 15 identified in the soils from the differently degraded marshes were lanceolate, rectangular, and elongate, which originated from Poaceae and Cyperaceae. Soil phytolith morphotype assemblages show potential for studying past vegetation and climatic succession in alpine wetlands. The soil phytolith and PhytOC content exhibited no significant differences between the NDM and LDM samples. Compared with the NDM soil, phytolith content was significantly lower in the MDM (33.8–58.8%) and SDM (52.7–65.4%) soils, respectively, and PhytOC content was also significantly lower (by 31.0–57.1% and 47.5–74.4%, respectively). The soil phytolith and PhytOC content decreased significantly with soil depth, especially once the marsh has become moderately degraded. Alpine marsh degradation reduced the accumulation of soil PhytOC by decreasing the PhytOC input flux, thereby altering the long-term carbon sequestration mechanism of phytoliths in this alpine-marsh wetland ecosystem.

Potassium (K) deficiency is widespread in Alfisols on which tea is grown, and quantifying the availability of K to the tea plants is important in designing fertilizer regimes and in ensuring that tea production systems remain sustainable. In this study, the contents of available K, its release characteristics, and the composition of K-bearing minerals were determined for Alfisols on which tea had been grown for 5, 10, 15, or 30 years. The contents of exchangeable K (EK), non-exchangeable K (NEK), K extracted with sodium tetraphenylboron, release threshold values of total labile K, and equilibrium K concentration increased as the age of the plantation increased. However, the content of EK even in the oldest plantations was far below the critical value for K deficiency (80 mg kg−1). The concentration of total labile K was higher than that of EK irrespective of the age of the plantation, which points to serious exhaustion of NEK reserves. Furthermore, compared to older plantations, the younger plantations contained less of illite and chlorite and more of kaolinite and vermiculite in the clay fraction of the soils. Chlorite and illite was significantly positive correlated to available K either in the surface layer (0–15 cm) or in the deeper layer (15–30 cm), whereas kaolinite was significantly and negatively correlated to available K at both depths. Although tea plantations increased the reserves of soil available K, the increase was not enough either to overcome the deficiency of available K—which continues to be extremely severe—or to prevent the distortion of clay minerals in Alfisols. Adequate inputs of K are therefore essential for increasing the inherent capacity of the Alfisols to supply K and, in turn, to obtain high yields and superior-quality tea.

Soil organic carbon (SOC) fractions play a crucial role in the carbon cycle of alpine wetland ecosystems and regional climate regulation. In the last decades, alpine marshes at Tibetan Plateau have undergone increased degradation. The effects of marsh degradation on soil labile and recalcitrant organic carbon fractions and on SOC stability remain unclear. In this study, we investigated changes in SOC fractions with different biochemical recalcitrance and stability in the marsh ecosystems with various levels of degradation in the Zoige Wetland, Eastern Qinghai-Tibet Plateau. Soil samples of relatively pristine marsh (RPM), lightly degraded marsh (LDM), moderately degraded marsh (MDM), heavily degraded marsh (HDM) and severely degraded marsh (SDM) were collected and analysed using the acid hydrolysis method. Compared with RPM, the concentrations of SOC labile fraction I (non-cellulosic polysaccharides), SOC labile fraction II (cellulose) and recalcitrant organic carbon (ROC) in degraded marshes decreased significantly: 29–97, 38–95 and 32–99%, respectively, except for the LDM. The SOC recalcitrance index (RIc) in the HDM and SDM was significantly lower than that in RPM by 11–35 and 15–47%, respectively; compared with RPM, the stability of organic carbon was significantly lower in the HDM and SDM. Additionally, the marsh degradation increased vertical variation in the concentrations of SOC fractions. The degradation of alpine marshes decreases the capacity for carbon (C) sequestration via decreasing the resistance of SOC to biodegradation, indicating that the alpine marsh degradation may weaken the carbon sink capacity of the Zoige Plateau, thus aggravating the global greenhouse effect.

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Background The obligate mutualism between fig trees (Ficus, Moraceae) and pollinating fig wasps (Agaonidae) is a model system for studying co-evolution due to its perceived extreme specificity, but recent studies have reported a number of examples of trees pollinated by more than one fig wasp or sharing pollinators with other trees. This will make the potential of pollen flow between species and hybridization more likely though only few fig hybrids in nature have been found. We reared pollinator fig wasps from figs of 13 Chinese fig tree species and established their identity using genetic methods in order to investigate the extent to which they were supporting more than one species of pollinator (co-pollinator). Results Our results showed (1) pollinator sharing was frequent among closely-related dioecious species (where pollinator offspring and seeds develop on different trees); (2) that where two pollinator species were developing in figs of one host species there was usually one fig wasp with prominent rate than the other. An exception was F. triloba, where its two pollinators were equally abundant; (3) the extent of co-pollinator within one fig species is related to the dispersal ability of them which is stronger in dioecious figs, especially in small species. Conclusions Our results gave more examples to the breakdown of extreme specificity, which suggest that host expansion events where pollinators reproduce in figs other than those of their usual hosts are not uncommon among fig wasps associated with dioecious hosts. Because closely related trees typically have closely related pollinators that have a very similar appearance, the extent of pollinator-sharing has probably been underestimated. Any pollinators that enter female figs carrying heterospecific pollen could potentially generate hybrid seed, and the extent of hybridization and its significance may also have been underestimated.

The enzymatic hydrolysis of glycosidically bound volatiles (GBVs) plays an important role in tea aroma formation during the tea manufacturing process. However, during the enzyme-active manufacturing process of oolong tea, most GBVs showed no reduction, while ( Z)-3-hexenyl-β-glucopyranoside significantly enhanced at the turnover stage. This study aimed to determine the reason for this increase in ( Z)-3-hexenyl-β-glucopyranoside. Continuous wounding stress in the turnover stage did not enhance the expression level of glycosyltransferase 1 ( CsGT1), while it induced a significant increase in the ( Z)-3-hexenol content ( p ≤ 0.05). Furthermore, observing the cell structures of tea leaves exposed to continuous wounding and subcellular localizations of CsGTs suggested that the interaction of ( Z)-3-hexenol (substrate) and CsGT1 (enzyme) was available. In conclusion, both continuous wounding and subcellular localizations led to a ( Z)-3-hexenyl-β-glucopyranoside enhancement mechanism during the oolong tea's turnover stage. These results advance our understanding of GBV formation during the tea manufacturing process and their relationship with the stress from the tea manufacturing process. In addition, the information will help us further evaluate contribution of GBVs to enzymatic formation of oolong tea aroma compounds.

Urbanization has progressively intensified over the past few decades, transforming the structure and function of urban ecosystems and influencing the concentrations and spatial distributions of phosphorus (P) in the soil. This study collected 177 surface soil samples (to a depth of 20 cm) to understand the dynamics of soil P along a gradient of urbanization from a densely urbanized central city to less human-affected suburbs to a new exurban satellite in Chengdu, China. The results showed that concentrations of soil total P (TP) and its fractions (except Water-Po, NaOH-Pi, and Residual-P) in the central city and exurban satellite were significantly higher than in suburban areas (p

Alpine marsh wetlands in the Qinghai-Tibetan Plateau are ecological hotspots for global carbon (C) cycling in Central Asia; however, the soil C sinks are increasingly limited by marsh degradation. To assess the physical mechanisms by which changes in the soil C sequestration occur, the distribution and functional groups of soil organic C (SOC) in aggregates along a marsh degradation gradient on the Zoige Plateau in China were investigated using soil samples collected from differently degraded marshes. Our results showed that, beyond the state of light degradation, the large aggregate content decreased significantly by 31.1–55.2%, while the micro-aggregate content increased significantly by 23.1–93.1%. The SOC content in the aggregates decreased significantly by 39.1–84.8% and the dominant aggregate size for SOC preservation decreased to small or micro-aggregate. Marsh degradation also decreased the relative ratio of aliphatic-C while increasing that of alcohol and phenolic-C, and polysaccharide-C. Index I (relative decomposition of SOC in aggregates) was 73.5–429.0% higher for degraded marshes than for relatively pristine marsh (RPM), while Index Ⅱ (relative recalcitrance of SOC in aggregates) was 13.8–79.5% lower in comparison. Therefore, we concluded that marsh degradation probably reduces the organic C sequestration capacity of soil by increasing the decomposition of SOC in aggregates after both the dominant aggregate size for SOC preservation and aggregate stability decreased. This result represents the physical mechanism by which the decrease in SOC content occurs in response to marsh degradation in alpine regions.

Siegesbeckia orientalis L. was identified as a novel Cd-hyperaccumulator and valuable phytoremediation material. However, the molecular mechanisms underlying Cd accumulation in S. orientalis are largely unknown. In this study, RNA-Seq analysis was performed to study the Cd-accumulating mechanisms in its roots with or without Cd treatment. The RNA-seq analysis generated 312 million pairs of clean reads and 78G sequencing data. De novo transcriptome assembly produced 355,070 transcripts with an average length of 823.59 bp and 194,207 unigenes with an average length of 605.68 bp. Comparative transcriptome analyses identified a large number of differentially expressed genes in roots under Cd stress, and functional annotation suggested that S. orientalis utilizes various biological pathways involving many gene networks working simultaneously to cope with the stress. This study revealed that four biological pathways were mainly involved in S. orientalis tolerance to Cd stress, including reactive oxygen species scavenging, phenylpropanoid biosynthesis pathway, Cd absorption and transport, and ABA signaling pathway. The genes related to photosynthesis and heavy metal transport are likely the potential candidates and could be further investigated to determine their roles in Cd tolerance in S. orientalis roots. These findings will be useful to understand the Cd accumulation mechanisms in S. orientalis and facilitate the study of phytoremediation at the molecular level in plants.

Siegesbeckia orientalis L. is a promising species for cadmium (Cd) phytoextraction with large biomass and fast growth rate, while little information about their intracellular mechanisms involved in Cd tolerance and detoxification has been explored. A soil pot experiment with total target Cd concentrations of 0, 10, 50, 100, and 150 mg kg-1 were designed to investigate the subcellular distribution, chemical forms and thiol synthesis characteristics of Cd in S. orientalis. More than 90% of Cd was bound to the soluble fractions (48.4-76.5%) and cell walls (19.9-46.3%). Increasing soil Cd concentrations enhanced Cd sequestration into the cell walls. Most of the Cd (69.8-82.7%) in the plant organ was mainly in the forms of pectate and protein integrated Cd and undissolved Cd phosphate, while a minor portion (6.8-20.9%) was in the forms of the inorganic Cd and the water soluble Cd. Nonprotein thiols and phytochelatins significantly increased with increasing soil Cd treatment levels, while glutathione concentrations had no obvious change trends. Therefore, intracellular detoxification mechanisms of Cd in S. orientalis mainly rely on formation of less toxic Cd chemical forms, store of a large amount of Cd in cell wall and synthesis of thiol compounds.

Jasmine lactone has a potent odor that contributes to the fruity, sweet floral aroma of tea ( Camellia sinensis). Our previous study demonstrated that jasmine lactone was mostly accumulated at the turnover stage of the oolong tea manufacturing process. This study investigates the previously unknown mechanism of formation of jasmine lactone in tea leaves exposed to multiple stresses occurring during the growth and manufacturing processes. Both continuous mechanical damage and the dual stress of low temperature and mechanical damage enhanced jasmine lactone accumulation in tea leaves. In addition, only one pathway, via hydroperoxy fatty acids from unsaturated fatty acid, including linoleic acid and α-linolenic acid, under the action of lipoxygenases (LOXs), especially CsLOX1, was significantly affected by these stresses. This is the first evidence of the mechanism of jasmine lactone formation in tea leaves and is a characteristic example of plant volatile formation in response to dual stress.

Excessive ammonium (NH4+) and phosphate (PO43−) in aquatic environments can cause serious eutrophication. Agricultural waste is an efficient adsorbent for nutrients removal and has good potential for comprehensive utilisation of resources. In this study, two Chinese medicinal herbal residues, Rhizoma Typhonium Gigantei (ZB) and Radix Glycyrrhizae Preparata (ZG), were implemented to simultaneously remove NH4+ and PO43− from water. Parameters such as adsorbent dosage, solution pH, contact time and initial concentration that influenced the adsorption process onto adsorbents, along with removal mechanism and practical performance were investigated. The microstructure of ZB was irregular with numerous spherical particles, while ZG displayed an uneven flaky structure with few rough grooves. The nutrients adsorption was significantly influenced by pH. The maximum adsorption capacity by ZB was 91.84 N mg g−1 and 71.81 P mg g−1. In addition, the maximum adsorption capacity recorded by ZG was 100.86 N mg g−1 and 89.51 P mg g−1 (pH, 8.0; dosage, 0.2 g L−1; initial concentration, 60 mg L−1; and contact time, 180 min, for both the herbal residues). The adsorption of NH4+ and PO43− was well described by the pseudo-second-order and intra-particle diffusion models, respectively. The Langmuir isotherm model is the best fit model for the adsorption equilibrium data, suggesting monolayer adsorption of NH4+ and PO43− by the two adsorbents. In addition, NH4+ was predominantly adsorbed by electrostatic attraction, ion exchange and complexation, whereas PO43− was predominantly adsorbed by intra-particle diffusion and ligand exchange. Practical application analysis demonstrated that ZG could remove and recover more NH4+ and PO43− from swine wastewater than ZB. Therefore, ZG exhibited a more significant potential to simultaneously remove and recover NH4+ and PO43− from wastewater.

The purpose of this study was to synthesize FeS/chitosan/biochar composite (FSBC) to remove Cr(VI). Results indicate that the modification of FeS particles and chitosan to biochar provided large specific surface area and more active adsorption sites. FSBC(1:1:1) have an enhanced Cr(VI) adsorption capacity of 103.93 mg g-1 at 0.01 g per 50 mL Cr(VI) solution compared with 19.97 mg g−1 for FeS particles and 22.45 mg g−1 for biochar. Increasing temperature promote Cr(VI) removal. By contrast, increasing Cl- and SO42- concentrates and solution pH prevented Cr(VI) adsorption. Cr(VI) removal could attribute to surface adsorption, reduction and precipitation. XPS results indicated that 76.07% of Cr(VI) removal was due to reduction or precipitation, and 23.93% could be ascribed to surface adsorption. After adsorption-desorption cycle, Cr(VI) removal capacities are 70.42, 65.33 and 11.67 mg g−1 for FSBC(1:1:1), FSBC(1:1:5) and FSBC(5:5:1), respectively. The study demonstrated that FSBC were high-effective adsorbents for Cr(VI) removal in the water environment.

The perturbation induced by a wall-mounted transverse circular cylinder element (TCCE) to a turbulent boundary layer (TBL) is studied using particle image velocimetry (PIV). Measurements are also performed on a smooth wall, which is used as baseline for comparison. The modification of the TBL caused by the sudden perturbation, in a statistical sense, is quantified by comparing the distributions of mean velocity, Reynolds stresses and shape factor in the two geometrical configurations. The impact of the TCCE on the TBL is found to extend more than 9 boundary-layer thickness downstream. Combining the side- and top-view PIV data indicates that the packet-like structures are stretched along the streamwise direction within a flat inclination angle when climbing over the TCCE, and retain their large spatial scales. The separated vortices induced downstream of the TCCE, are quickly lifted up to form the hairpin vortices within strong swirling strength. Then, the robust hairpin packets are generated downstream through the auto-generation scenario, which occupies the low-speed regions beneath the residual hairpin packet’s heads and impairs the process that the low-momentum fluids feed the concentrated vorticity into the residual hairpin heads. Meanwhile, the streamwise-stretched low-momentum regions (LMRs) are redeveloped in the inner layer underneath the new-generated hairpin packets. Further downstream, even though the residual hairpin packets’ heads are merged by the robust hairpin packets, they are not completely dissipated, and still interact with the new-generated hairpin packets in the outer layer to the end of the field of view.

Banana is a tropical fruit widely accepted by people over the world. Its chemical composition is critical for its organoleptic properties and nutritional value. In this work, the metabolite changes during postharvest senescence were investigated using NMR spectroscopy. The 1D and 2D NMR spectroscopic information revealed the primary and secondary metabolites in banana fruit, including organic acids, amino acids, carbohydrates and phenolics. Bananas at five senescence stages showed similar chemical profiles, but the levels of the individual compounds varied to a large extent. The principal metabolites responsible for postharvest senescence of banana were valine, alanine, aspartic acid, choline, acetate, glucose, malic acid, gallic acid and dopamine. At stage V, ethanol was present due to the conversion of glucose. Salsolinol was generated due to the conversion of dopamine. This was a characteristic marker for the postharvest senescence of banana fruit.

Soil washing, an emerging method for treating soils contaminated by heavy metals, requires an evaluation of its efficiency in simultaneously removing different metals, the quality of the soil following remediation, and the reusability of the recycled washing agent. In this study, we employed N,N-bis (carboxymethyl)-l-glutamic acid (GLDA), a novel and readily biodegradable chelator to remove Cd, Pb, and Zn from polluted soils. We investigated the influence of washing conditions, including GLDA concentration, pH, and contact time on their removal efficiencies. The single factor experiments showed that Cd, Pb, and Zn removal efficiencies reached 70.62, 74.45, and 34.43% in mine soil at a GLDA concentration of 75mM, a pH of 4.0, and a contact time of 60min, and in polluted farmland soil, removal efficiencies were 69.12, 78.30, and 39.50%, respectively. We then employed response surface methodology to optimize the washing parameters. The optimization process showed that the removal efficiencies were 69.50, 88.09, and 40.45% in mine soil and 71.34, 81.02, and 50.95% in polluted farmland soil for Cd, Pb, and Zn, respectively. Moreover, the overall highly effective removal of Cd and Pb was connected mainly to their highly effective removal from the water-soluble, exchangeable, and carbonate fractions. GLDA-washing eliminated the same amount of metals as EDTA-washing, while simultaneously retaining most of the soil nutrients. Removal efficiencies of recycled GLDA were no >5% lower than those of the fresh GLDA. Therefore, GLDA could potentially be used for the rehabilitation of soil contaminated by heavy metals.

The Lycium ruthenicum (Lr) fruit is a widely used nutritional food that contains various bioactive components such as anthocyanin and spermidine derivatives. In the present study, ultra-high-performance liquid chromatography with tandem mass spectrometry was utilized to profile the metabolic dynamics of four developmental stages of Lr fruit. A total of 49 compounds, including anthocyanin, alkaloids, hydroxycinnamic acid derivatives, flavonoids, and amino acids, were tentatively identified. Principal component analysis distinguished the fruit at four developmental stages using 15 (9 were tentatively identified) potential marker compounds. Pearson correlation analysis suggested that anthocyanin and spermidine derivative hexoses had a strong positive correlation coefficient. A glucosyltransferase (HG27071) was confirmed to glucosylate both anthocyanidin and spermidine derivative in vitro. Our results provide insight into the metabolic linkages among bioactive components in Lr fruits. The glucosyltransferase identified in this study will promote its potential use in functional foods and natural pigment resources.

Table S1. Composition of volatiles from four sandalwood tissues. Table S2. Length distribution of assembled transcripts and unigenes. Table S3. Terpene synthase identified based on transcriptome data. Table S4. Information of three SaTPSs isolated from S. album. Table S5. TPS proteins from other plant species used in phylogenetic analysis. Table S6. Predicted chloroplast transit peptides. Table S7. In vitro assay products that each recombination SaTPS and FPP or GPP. Table S8. List of primers used in this study. Table S9 Restriction enzymes used for YPF plasmid construction and expression vectors. Figure S1. Length distribution of S. album unigenes. Figure S2. Agarose gel electrophoresis of three SaTPS ORFs. Figure S3. Comparison of deduced amino acid sequences of SaTPS1 and two other TPSs. Figure S4. Comparison of transcript levels of SaTPSs. Figure S5. SDS-PAGE analysis of recombinant proteins. Figure S6. In vitro enzymatic assays of recombinant SaTPS1 using GPP and Mn2+. Figure S7. In vitro enzyme assays of recombinant SaTPS2 using FPP and Mn2+. Figure S8. In vitro enzyme assays of recombinant SaTPS2 using GPP and Mn2+. Figure S9. In vitro enzymatic assays of recombinant SaTPS3 using GPP and Mn2+. Figure S10. Michaelis-Menten plots for three SaTPSs. Figure S11â 28. Characterization of six authentic standards by NMR. (PDF 2014 kb)

Soil culture experiments were carried out to study the effects of the mixture of Amaranthus chinense L. straw and phosphate rock on soil pH, available phosphorus (AP), available potassium (AK) and DTPA-Cd content in Cd polluted soil. The results showed that: (1) 2% phosphate rock powder combined with 1%, 2%, 3% of Amaranthus chinense L. straw can significantly increase soil pH, AP and AK content. Compared with CK, pH was increased by 0.42~0.56, 0.53~0.70 and 0.47~0.73 units, respectively, and AP was increased by 19.03%~32.62%, 14.91%~43.63% and 18.88%~58.01%, respectively, and AK was increased by 201.46%~234.66%, 210.5%~266.56% and 184.07%~224.98%, respectively. (2) The DTPA-Cd content in soil decreased significantly after adding three different ratios of compound materials, which were 1.75%~9.01%, 2.86%~10.02% and 0.98%~8.7% lower than CK, respectively. In summary, the mixture of 1% Amaranthus chinense L. straw and 2% phosphate rock powder had the best passivation effect on Cd.

In this study, we took Oenanthe javanica DC. as experimental material, and we used floating-bed cultivation technique to investigate the removal effect of TN and TP in 3 kinds of eutrophic water to explore the feasibility of using Oenanthe javanica DC. in ecological remediation. The results showed that the removal rates for NH4+-N, NO3--N and PO43--P of Oenanthe javanica DC. were 94.19%-99.35%, 89.52%-98.10% and 77.63%-79.74%, respectively. The removal rates for TN and TP were 91.67%-96.93% and 72.53%-79.74%, while the contribution of Oenanthe javanica DC. to TN and TP absorption in eutrophic water were 46.43% -63.44% and 50.54%-38.08%, respectively, indicating that the purification for TN and TP in eutrophic water by Oenanthe javanica DC. was good under the experimental conditions, and Oenanthe javanica DC. uptake played an important role. Therefore, Oenanthe javanica DC. can be used for ecological restoration of eutrophic water.

In this paper, hyperaccumulator straw (Solanum nigrum L., Amaranthus chinense L., and Siegesbeckia orientalis L.) and phosphate rock powder were selected as materials, a pot experiment was used to study the effects of three compounding modifiers on the growth, nutritional quality and cadmium (Cd) content of Chinese cabbage. The results showed that: (1) The combination of Siegesbeckia orientalis + phosphate rock powder can significantly promote the growth of Chinese cabbage, while Solanum nigrum + phosphate rock powder and Amaranthus chinense + phosphate rock powder have no effect on the growth of Chinese cabbage. (2) The combination of Solanum nigrum and phosphate rock powder increased the content of soluble sugar, soluble protein and VC in shoots of Chinese cabbage by 64.33%, 16.27% and 2.2%, respectively, and the nitrite content decreased by 34.58%, which improved the quality of Chinese cabbage. (3) Different compounding modifiers can significantly reduce the Cd content in shoots of Chinese cabbage, and the reduction of Solanum nigrum + phosphate rock powder is the largest, reaching 61.29%. In conclusion, all three modifiers can improve the nutritional quality and reduce the Cd content in the shoots of Chinese cabbage, and Solanum nigrum + phosphate rock powder has the best effect.

Estimating the spatial distribution of soil nitrogen at different scales is crucial for improving soil nitrogen use efficiency and controlling nitrogen pollution. We evaluated the spatial variability of soil total nitrogen (TN) and available nitrogen (AN) in the Fujiang River Valley, a typical hilly region composed of low, medium and high hills in the central Sichuan Basin, China. We considered the two N forms at single hill, landscape and valley scales using a combined method of classical statistics, geostatistics and a geographic information system. The spatial patterns and grading areas of soil TN and AN were different among hill types and different scales. The percentages of higher grades of the two nitrogen forms decreased from low, medium to high hills. Hill type was a major factor determining the spatial variability of the two nitrogen forms across multiple scales in the valley. The main effects of general linear models indicated that the key affecting factors of soil TN and AN were hill type and fertilization at the single hill scale, hill type and soil type at the landscape scale, and hill type, slope position, parent material, soil type, land use and fertilization at the valley scale. Thus, the effects of these key factors on the two soil nitrogen forms became more significant with upscaling.

Complex and dynamic land-use patterns have been observed globally due to rapid urbanization and persistent human disturbance. Analyzing the effect of urbanization on carbon (C) stocks is a key step toward enhancing C sequestration and mitigating emissions of carbon dioxide. In a newly urbanized area of western Chengdu, China, we analyzed soil organic C (SOC), soil inorganic C (SIC) stocks down to 1 m, and aboveground vegetation C, and we discussed the effects of land use, density of construction and roads, and distance from the urban center on SOC and SIC density. The SOC, SIC stocks down to 1 m, and aboveground vegetation C stocks were 1.08 × 109 kg, 4.67 × 107 kg, and 1.58 × 107 kg, respectively. Our analyses of SOC and SIC density provided three results: (1) it was significantly higher in rural than in urban land-use types; (2) it tended to decrease as the density of construction and roads increased; and (3) it increased with distance far from the urban center. The results indicated that urbanization led to SOC and SIC loss in our study area. SOC and SIC loss will be alleviated by decreasing the construction and road density and increasing green space area.

Soil labile organic carbon fractions (LOCF) are valuable indicators of changes in soil quality and soil total organic carbon (TOC), and they are easily influenced by changes in soil management practice. To explore the sensitivity of LOCF and their enzymatic conversion under straw mulch for scientific management of crop straw use on the Chengdu plain, a straw mulch field experiment was conducted to observe the LOCF changes and explore their relationships with C-cycle enzymes during wheat growth. The treatments included no fertilizer or straw (Control), only mineral fertilizer (MF), 10% rice straw nitrogen (N) plus 90% fertilizer N (RS1), 20% rice straw N plus 80% fertilizer N (RS2), 30% rice straw N plus 70% fertilizer N (RS3), 100% rice straw (RS). The water-soluble organic carbon (WSOC) and microbial biomass carbon (MBC) under straw treatments in the 0–20 cm soil layer were significantly higher than those of Control and MF treatments from the seedling stage, and showed significant differences among straw treatments from the tillering stage. Correspondingly, the dissolved organic carbon (DOC) and permanganate oxidized carbon (POXC) showed no obvious differences among straw treatments in most growth stages. Therefore, WSOC and MBC were the most sensitive indicators for assessing soil organic carbon (SOC) change under straw mulch. Moreover, stepwise multiple linear regression revealed that cellulase and β-glucosidase were significantly positive impact factors for LOCF in the two soil layers, while polyphenol oxidase had both positive and negative impacts on WSOC at different soil layers, and peroxidase was a negative factor for LOCF.

The water-soluble bioactive polysaccharides can contribute to the health benefits of Lycium barbarium fruit. However, the structure characteristics of these polysaccharides remain unclear yet. An important polysaccharide (LBPA) was isolated and purified from L. barbarium in this work. It was identified by chemical and spectroscopic methods as arabinogalactan with β-d-(1→6)-galactan as backbone, which was different to any reported polysaccharides from this species before. This arabinogalactan was comprised of Araf, Galp, GlcpA and Rhap with a molar ratio of 9.2:6.6:1.0:0.9. The side chains, including α-l-Araf-(1→, α-l-Araf-(1→5)-α-l-Araf-(1→, β-l-Araf-(1→5)-α-l-Araf-(1→ and α-l-Rhap-(1→4)-β-d-GlcpA-(1→6)-β-d-Galp-(1→, were linked to β-d-(1→6)-galactan at O-3. The putative structure was drawn as below. The molecular weight was determined to be 470,000g/mol by gel permeation chromatography.

Fruit of two different papaya cultivars (‘Sui huang’, yellow flesh, and ‘Sui hong’, red flesh) were characterized in terms of carotenoid and volatile profiles throughout storage at 25 °C. The results showed that ‘Sui huang’ cultivar exhibited significantly lower carotenoid contents than ‘Sui hong’, which accounted for the different color characteristic. The analyses of HPLC coupled to mass spectrometry showed that zeaxanthin, β-cryptoxanthin and and β-carotene were identified as the most abundant carotenoids in ‘Sui huang’ fruit while the most abundant carotenoids were lycopene, followed by β-carotene, zeaxanthin and β-cryptoxant hin in ‘Sui hong’ fruit. The high expression of carotenoid cleavage dioxygenase gene (CpCCD1) in ‘Sui hong’ papaya fruit might stimulate the degradation of β-carotene and lycopene and then form the specific volatiles of 6-methyl-5-hepten-2-one and β-ionone.

Soil washing with natural chelators to remediate metal-contaminated soils has been gained attention by researchers. However, the abilities of the chelators to remediate the multiple metal polluted soils are less effective. This study employed zero-valent iron nanoparticle (nZVI) to enhance the removal efficiencies of citric (CA), tartaric (TA) and oxalic acids (OA), and evaluate their feasibility. Results showed that metal removal efficiencies increased with the increasing concentration of nZVI and soil-liquid ratio, decreased with the increasing solution pH. The kinetic simulation indicated that pseudo-first-order and pseudo-second-order models could be used for describing the washing processes. Additionally, metal removals were significantly improved by addition of nZVI (p 0.05). The highest enhancements of soil Cd, Pb and Zn removals under solution pH of 4.0, soil-liquid ratio of 1:20 and washing time of 120 min reached 12.83% (OA- nZVI), 24.92% (CA-nZVI) and 11.64% (OA- nZVI) for mine soil, and 19.24% (TA- nZVI), 18.16% (CA-nZVI) and 8.93% (OA- nZVI) for farmland soil, respectively. After soil washing, the exchangeable forms and the environmental risks of residual metals were markedly diminished in soils. Therefore, the combinations of the organic acids and nZVI are the feasible practices to repair the soils contaminated by heavy metals.

Soil washing with chelators is a promising and efficient method of remediating metals-contaminated soils. However, the toxicity of residual metals and the effects on soil microbial properties have remained largely unknown after washing. In this study, we employed four biodegradable chelators for removal of metals from contaminated soils: iminodisuccinic acid (ISA), glutamate-N,N-diacetic acid (GLDA), glucomonocarbonic acid (GCA), and polyaspartic acid (PASP). The maximum removal efficiencies for Cd, Pb, and Zn of 85, 55, and 64% and 45, 53, and 32% were achieved from farmland soil and mine soil using biodegradable chelators, respectively. It was found that the capacity of ISA and GLDA to reduce the labile fraction of Cd, Pb, and Zn was similar to that of the conventional non-biodegradable chelator ethylenediaminetetraacetic acid (EDTA). The leachability, mobility, and bioaccessibility of residual metals after washing decreased notably in comparison to the original soils, thus mitigating the estimated environmental and human health risks. Soil β-glucosidase activity, urease activity, acid phosphatase activity, microbial biomass nitrogen, and microbial biomass phosphorus decreased in the treated soils. However, compared with EDTA treatment, soil enzyme activities distinctly increased by 5–94% and overall microbial biomass slightly improved in the remediated soils, which would facilitate reuse of the washed soils. Based on soil toxicity tests that employed wheat seed germination as the endpoint of assessment, the washed soils exhibited only slight effects especially after ISA and GLDA treatments, following high-efficiency metal removal. Hence, ISA and GLDA appear to possess the greatest potential to rehabilitate polluted soils with limited toxicity remaining.

Cuticular wax forms a hydrophobic layer covering aerial plant organs and acting as a protective barrier against biotic and abiotic stresses. Compared with well-known wax biosynthetic pathway, molecular regulation of wax biosynthesis is less known. Here, we show that rice OsWS1, a member of the membrane-bound O-acyl transferase gene family, involved in wax biosynthesis and was regulated by an osa-miR1848. OsWS1-tagged green fluorescent protein localized to the endoplasmic reticulum (ER). Compared with wild-type rice, OsWS1 overexpression plants displayed a 3% increase in total wax, especially a 35% increase in very long-chain fatty acids, denser wax papillae around the stoma, more cuticular wax crystals formed on leaf and stem surfaces, pollen coats were thicker and more seedlings survived after water-deficit treatment. In contrast, OsWS1-RNAi and osa-miR1848 overexpression plants exhibited opposing changes. Gene expression analysis showed that overexpression of osa-miR1848 down-regulated OsWS1 transcripts; furthermore, expression profiles of OsWS1 and osa-miR1848 were inversely correlated in the leaf, panicle and stem, and upon water-deficit treatment. These results suggest that OsWS1 is regulated by osa-miR1848 and participates in cuticular wax formation.

Phytosterols are membrane components or precursors for brassinosteroid (BR) biosynthesis. As they cannot be transported long distances, their homeostasis is tightly controlled through their biosynthesis and metabolism. However, it is unknown whether microRNAs are involved in their homeostatic regulation. Rice (Oryza sativa) plants transformed with microRNA osa-miR1848 and its target, the obtusifoliol 14α-demethylase gene, OsCYP51G3, were used to investigate the role of osa-miR1848 in the regulation of phytosterol biosynthesis. osa-miR1848 directs OsCYP51G3 mRNA cleavage to regulate phytosterol and BR biosynthesis in rice. The role of OsCYP51G3 as one of the osa-miR1848 targets is supported by the opposite expression patterns of osa-miR1848 and OsCYP51G3 in transgenic rice plants, and by the identification of OsCYP51G3 mRNA cleavage sites. Increased osa-miR1848 and decreased OsCYP51G3 expression reduced phytosterol and BR concentrations, and caused typical phenotypic changes related to phytosterol and BR deficiency, including dwarf plants, erect leaves, semi-sterile pollen grains, and shorter cells. Circadian expression of osa-miR1848 regulated the diurnal abundance of OsCYP51G3 transcript in developing organs, and the response of OsCYP51G3 to salt stress. We propose that osa-miR1848 regulates OsCYP51G3 expression posttranscriptionally, and mediates phytosterol and BR biosynthesis. osa-miR1848 and OsCYP51G3 might have potential applications in rice breeding to modulate leaf angle, and the size and quality of seeds.