Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellul...Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch.展开更多
Rice cooking and eating qualities(CEQ)are mainly determined by cooked rice textural parameters and starch physicochemical properties.However,the genetic bases of grain texture and starch properties in rice have not be...Rice cooking and eating qualities(CEQ)are mainly determined by cooked rice textural parameters and starch physicochemical properties.However,the genetic bases of grain texture and starch properties in rice have not been fully understood.We conducted a genome-wide association study for apparent amylose content(AAC),starch pasting viscosities,and cooked rice textural parameters using 279 indica rice accessions from the 3000 Rice Genome Project.We identified 26 QTLs in the whole population and detected single nucleotide polymorphisms(SNPs)with the lowest P-value at the Waxy(Wx)locus for all traits except pasting temperature and cohesiveness.Additionally,we detected significant SNPs at the SUBSTANDARD STARCH GRAIN6(SSG6)locus for AAC,setback(SB),hardness,adhesiveness,chewiness(CHEW),gumminess(GUM),and resilience.We subsequently divided the population using a SNP adjacent to the Waxy locus,and identified 23 QTLs and 12 QTLs in two sub-panels,WxT and WxA,respectively.In these sub-panels,SSG6 was also identified to be associated with pasting parameters,including peak viscosity,hot paste viscosity,cold paste viscosity,and consistency viscosity.Furthermore,a candidate gene encoding monosaccharide transporter 5(OsMST5)was identified to be associated with AAC,breakdown,SB,CHEW,and GUM.In total,39 QTLs were co-localized with known genes or previously reported QTLs.These identified genes and QTLs provide valuable information for genetic manipulation to improve rice CEQ.展开更多
Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a comm...Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a common characteristic of Gossypium genus and its relatives,appearing as visible dark opaque dots in most tissues and organs of cotton plants.Secondary metabolites,such as gossypol,synthesized and stored in the cavities of pigment glands act as natural phytoalexins,but are toxic to humans and other monogastric animals.However,only a few cotton genes have been identified as being associated with pigment gland morphogenesis to date,and the developmental processes and regulatory mechanism involved in pigment gland formation remain largely unclear.Here,the research progress on the process of pigment gland morphogenesis and the genetic basis of cotton pigment glands is reviewed,for providing a theoretical basis for cultivating cotton with the ideal pigment gland trait.展开更多
[Objectives] This study was conducted to investigate the scientific prevention and control of Solanum nigrum L. [Methods] Through experiments on S. nigrum from different sources, it was found that glyphosate stress ha...[Objectives] This study was conducted to investigate the scientific prevention and control of Solanum nigrum L. [Methods] Through experiments on S. nigrum from different sources, it was found that glyphosate stress had significant effects on antioxidant enzyme activity and oxidative damage of sensitive S. nigrum plants. [Results] Sensitive S. nigrum showed oxidative damage under glyphosate stress, while resistant S. nigrum responded to adversity damage by improving its antioxidant enzyme activity. The experimental results showed that the antioxidant enzymes and reduced glutathione of S. nigrum had certain metabolic detoxification effects under glyphosate stress. [Conclusions] This study provides a theoretical basis for scientific prevention and control of S. nigrum , and has a certain reference value for revealing the glyphosate resistance mechanism of S. nigrum .展开更多
Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological an...Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological and molecular regulation of tillering has been intensively studied in rice and wheat.However,tillering research on barley is scarce.This review used the recent advances in bioinformatics to map all known and potential barley tiller development genes with their chromosomal genetic and physical positions.Many of them were mapped for the first time.We also discussed tillering regulation at genetic,physiological,and environmental levels.Moreover,we established a novel link between the genetic control of phytohormones and sugars with tillering.We provided evidence of how environmental cues and cropping systems help optimize the tiller number.This comprehensive review enhances the understanding of barley’s physiological and genetic mechanisms controlling tillering and other developmental traits.展开更多
As the‘Green Revolution’gene,SD1(encoding GA20ox2),has been widely applied to improve yield in rice breeding.However,research on its transcriptional regulation is limited.Here,we identified a transcription factor Os...As the‘Green Revolution’gene,SD1(encoding GA20ox2),has been widely applied to improve yield in rice breeding.However,research on its transcriptional regulation is limited.Here,we identified a transcription factor OsbZIP01,which can suppress the expression of SD1 and regulate gibberellin(GA)biosynthesis in rice.Knockout mutants of OsbZIP01 exhibited increased plant height,while the overexpression lines showed a semi-dwarf phenotype and diminished germination rate.Furthermore,the semi-dwarf phenotype of OE-bZIP01,was caused by the reduced internode length,which was accompanied by a thin stem width.The predominant expression of OsbZIP01 was observed in leaves and sheaths.OsbZIP01 protein was localized in the nucleus and showed transcriptional repression activity.In addition,OsbZIP01 could directly bind to the promoter of the OsSD1 gene,and inhibit its transcription.The semi-dwarf phenotype of OE-bZIP01 could be rescued by exogenous GA_(3).Meanwhile,the bzip01 sd1 double mutant showed a shorter shoot length compared with the wild type,indicating that OsbZIP01 regulated plant growth mainly through the GA biosynthesis pathway.Collectively,OsbZIP01 negatively regulates GA biosynthesis by restraining SD1 transcription,thereby affecting plant growth and development.展开更多
Lesion mimic mutants(LMMs) are advantageous materials for studying programmed cell death(PCD).Although some rice LMM genes have been cloned, the diversity of functions of these genes indicates that the mechanism of ce...Lesion mimic mutants(LMMs) are advantageous materials for studying programmed cell death(PCD).Although some rice LMM genes have been cloned, the diversity of functions of these genes indicates that the mechanism of cell death regulation in LMMs needs further study. In this study, we identified a rice light-dependent leaf lesion mimic mutant 4(llm4) that showed abnormal chloroplast structure, photoinhibition, reduced photosynthetic protein levels, massive accumulation of reactive oxygen species(ROS), and PCD. Map-based cloning and complementation testing revealed that LLM4 encodes zeaxanthin epoxidase(ZEP), an enzyme involved in the xanthophyll cycle, which functions in plant photoprotection,ROS scavenging, and carotenoid and abscisic acid(ABA) biosynthesis. The ABA content was decreased,and the contents of 24 carotenoids differed between the llm4 mutant and the wild type(WT). The llm4mutant showed reduced dormancy and greater sensitive to ABA than the WT. We concluded that the mutation of LLM4 resulted in the failure of xanthophyll cycle, in turn causing ROS accumulation. The excessive ROS accumulation damaged chloroplast structure and induced PCD, leading eventually to the formation of lesion mimics.展开更多
Cultivating salt-tolerant crops is a feasible way to effectively utilize saline-alkali land and solve the problem of underutilization of saline soils.Quinoa,a protein-comprehensive cereal in the plant kingdom,is an ex...Cultivating salt-tolerant crops is a feasible way to effectively utilize saline-alkali land and solve the problem of underutilization of saline soils.Quinoa,a protein-comprehensive cereal in the plant kingdom,is an exceptional crop in terms of salt stress tolerance level.It seems an excellent model for the exploration of salt-tolerance mechanisms and cultivation of salt-tolerant germplasms.In this study,the seeds and seedlings of the quinoa cultivar Shelly were treated with different concentrations of NaCl solution.The physiological,biochemical characteristics and agronomic traits were investigated,and the response patterns of three salt stress-responsive genes(SSRGs)in quinoa were determined by real-time PCR.The optimum level of stress tolerance of quinoa cultivar Shelly was found in the range of 250–350 mM concentration of NaCl.Salt stress significantly induced expression of superoxide dismutase(SOD),peroxidase(POD),and particularly betaine aldehyde dehydrogenase(BADH).BADH was discovered to be more sensitive to salt stress and played an important role in the salt stress tolerance of quinoa seedlings,particularly at high NaCl concentrations,as it displayed upregulation until 24 h under 100 mM salt treatment.Moreover,it showed upregulation until 12 h under 250 mM salt stress.Taken together,these results suggest that BADH played an essential role in the salt-tolerance mechanism of quinoa.Based on the expression level and prompt response induced by NaCl,we suggest that the BADH can be considered as a molecular marker for screening salt-tolerant quinoa germplasm at the early stages of crop development.Salt treatment at different plant ontogeny or at different concentrations had a significant impact on quinoa growth.Therefore,an appropriate treatment approach needs to be chosen rationally in the process of screening salt-tolerant quinoa germplasm,which is useful to the utilization of saline soils.Our study provides a fundamental information to deepen knowledge of the salt tolerance mechanism of quinoa for the development of salt-tolerant germplasm in crop breeding programs.展开更多
[Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to stud...[Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to study the effects of Sb stress on root growth and Sb accumulation and transport of the root system of cultivated ramie Zhongzhu No.1, as well as on the physiological characteristics of ramie leaves. [Results] The plant height and root dry weight and volume of Zhongzhu No.1 showed an effect of "promoting at low concentrations and inhibiting at high concentrations" with the increase of Sb concentration, and decreased significantly at the concentration of 4 000 mg/kg, but no obvious toxic growth symptoms were observed. The content of Sb in roots(289.7-508.6 mg/kg) and the root-shoot transfer factor(0.09-0.57) of Zhongzhu No.1 increased with the increase of soil Sb concentration, but the change of Sb bioconcentration factor in roots was opposite, indicating that high concentrations of Sb in soil could promote the absorption of Sb in roots and the transport of Sb to the aboveground part, but the Sb enrichment capacity of roots was relatively reduced with the increase of soil Sb. Sb stress had a certain impact on the physiological characteristics of ramie leaves. With the increase of Sb treatment concentration, MDA, POD and SOD showed a change trend of "first increasing and then decreasing", while CAT gradually increased, indicating that Sb stress caused changes in the physiological characteristics of ramie leaves, thereby affecting plant growth and development. [Conclusions] This study provides a theoretical basis for ecological restoration of ramie in mining areas.展开更多
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex...With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.展开更多
[Objectives] To explore the effects of antimony(Sb) in different valence states on the growth and Sb bioconcentration and transfer of wild ramie(Boehmeria nivea). [Methods] A pot experiment was conducted to study the ...[Objectives] To explore the effects of antimony(Sb) in different valence states on the growth and Sb bioconcentration and transfer of wild ramie(Boehmeria nivea). [Methods] A pot experiment was conducted to study the effects of Sb(Ⅲ) and Sb(Ⅴ) stress on plant height, biomass, leaf SPAD value, Sb contents in various organs, Sb bioconcentration and transfer factors, and other indexes. [Results] Both kinds of Sb treatments showed a trend of "first increasing and then decreasing" in plant height as Sb concentration increased. The plant heights in Sb(Ⅲ) treatments with a concentration lower than 1 000 mg/kg and Sb(Ⅴ) treatments with concentrations lower than 4 000 mg/kg were significantly higher than that of the control check(CK);and the Sb(Ⅲ) treatment of the high concentration(4 000 mg/kg) resulted in a significant decrease in plant height, while the 8 000 mg/kg Sb(Ⅴ) treatment still showed an increase in plant height, indicating that the toxicity of Sb(Ⅴ) to wild ramie was significantly lower than that of Sb(Ⅲ). The Sb(Ⅲ) treatments with a concentration lower than 2 000 mg/kg had little effect on the dry weight of the aboveground part, while the treatment with a higher concentration showed a significant decrease;and the dry weights in various concentrations of Sb(Ⅴ) treatments showed no significant differences, but they were significantly higher than the CK and corresponding concentration of Sb(Ⅲ) treatment. Both types of Sb stress could promote the increase of SPAD value in wild ramie leaves, and the performance was significantly higher than the CK. As the concentration of Sb treatment increased, the Sb content in both the aboveground and underground parts showed a significant increase;and the comparison of Sb content under corresponding concentrations of the two types of Sb treatments showed that in the aboveground part, Sb(Ⅲ) was higher than Sb(Ⅴ), while in the underground part, the opposite was true. The bioconcentration factor(BF) of Sb decreased with the increase of Sb treatment concentration overall, and the value of Sb(Ⅴ) was smaller than that of Sb(Ⅲ), but both kinds of Sb stress were significantly smaller than the CK. The transfer factor(TF) of Sb in wild ramie showed a trend of "increasing first and then decreasing" with the concentration of Sb treatment, and various treatments of Sb(Ⅲ) were higher than the CK, with significant differences, while among various treatments of Sb(Ⅴ), except treatment B3, the reduction of which was not significant, other Sb(Ⅴ) treatments showed significant decreases. Comparing the two types of Sb treatments, the BF and TF values of Sb in wild ramie under Sb(Ⅲ) treatments were higher than those under Sb(Ⅴ) treatments, and the TF reached a significant level, indicating that the Sb transport ability of wild ramie under Sb(Ⅲ) treatments was stronger. [Conclusions] This study provides a theoretical basis for the mining of wild ramie Sb restoration genes and the application of large-scale cultivation in ecological restoration.展开更多
Arbuscular mycorrhizal fungi(AMF)are important members of the plant microbiome and affect the uptake and transfer of mineral elements by forming a symbiotic relationship with plant roots.Nitrogen(N),as an important mi...Arbuscular mycorrhizal fungi(AMF)are important members of the plant microbiome and affect the uptake and transfer of mineral elements by forming a symbiotic relationship with plant roots.Nitrogen(N),as an important mineral element,can directly affect plant growth and development at different N levels.It has been confirmed that inoculation with AMF can improve the efficiency of N utilization by plants.However,there are still fewer reports on the dynamic relationship between arbuscular mycorrhizal and plant secondary metabolites at different nitrogen levels.In this experiment,the physiological indexes and genes related to saponin synthesis were determined by applying different concentration gradients of nitrogen to the medicinal plant P.polyphylla var.yunnanensis infested by AMF as the test material.It was found that nitrogen addition increased the biomass,chlorophyll content,and nutrient content of above-and below-ground plant parts and increased the content of saponin content of P.polyphylla var.yunnanensis to some extent,but AMF inoculation increased the saponin content of P.polyphylla var.yunnanensis more significantly.AMF inoculation also promoted the expression of genes related to the saponin synthesis pathway,including 3-hydroxy-3-methylglutaryl coenzyme A synthase(HMGS),squalene epoxidase 1(SE1),and cycloartenol synthase(CAS),which is in according with the accumulation of saponin in plants.It also may increase the saponin content of AMF plants by altering the expression of P450s and UGTs related to saponin synthesis.展开更多
The growth rate method was adopted to measure the inhibitory effect of curcumin,tetrahydrocurcumin,demethoxycurcumin,and bisdemethoxycurcumin on the mycelial growth of Botrytis cinerea and Colletotrichum gloeosporioid...The growth rate method was adopted to measure the inhibitory effect of curcumin,tetrahydrocurcumin,demethoxycurcumin,and bisdemethoxycurcumin on the mycelial growth of Botrytis cinerea and Colletotrichum gloeosporioides.The results showed that the four curcuminoids inhibited the mycelial growth of the two pathogens in a concentration-dependent manner.Bisdemethoxycurcumin at 600 mg/L exerted the strongest inhibitory effect on the mycelial growth of B.cinerea and C.gloeosporioides,with the relative inhibition rates of 98.19%and 100%,respectively;followed by demethoxycurcumin;curcumin exerted the worst inhibitory effect.Toxicity test results also showed that four curcuminoids all had a certain toxicity to B.cinerea and C.gloeosporioides,among which,bisdemethoxycurcumin exhibited the strongest toxicity,with the EC_(50)of 131.125 and 122.235 mg/L,respectively;while curcumin had the lowest toxicity,with the EC_(50)of 273.143 and 194.943 mg/L,respectively.展开更多
In practice, pesticides are usually applied simultaneously or one after another for crop protection, and this type of pesticide application often leads to a combined contamination of pesticide residues in the soil env...In practice, pesticides are usually applied simultaneously or one after another for crop protection, and this type of pesticide application often leads to a combined contamination of pesticide residues in the soil environment. A laboratory study was conducted to investigate the influence of chlorothalonil on chlorpyrifos degradation and its effects on soil bacterial, fungal, and actinomycete populations. Under the experimental conditions here, the half-lives of chlorpyrifos alone, and in combination with chlorothalonil, at the recommended and double dosages, were measured to be 3.24, 2.77, and 2.63 d, respectively. Chlorpyrifos degradation was not significantly altered by its combination with chlorothalonil. However, the inhibitory effect of chlorpyrifos on soil microorganisms was increased by its combination with chlorothalonil, and the increase was related to the levels of chlorothalonil added. Compared to those in the controls, the populations of bacteria, fungi, and actinomycetes were significantly reduced by 44.1%, 61.1%, and 72.8%, respectively, on the first day after treatment (DAT) by chlorpyrifos alone. With the addition of chlorothalonil, the inhibition was increased to 55.2%, 79.3%, and 85,8% at the recommended dosage, and 86.0%, 94.1%, and 90.8% at the double dosage, at one DAT, respectively. The results suggested that combined effects should be taken into account to assess the actual impacts of pesticide applications.展开更多
The solar radiation intensity and duration are continuously decreasing in the major wheat planting area of China. As a con- sequence, leaf senescence, photosynthesis, grain filling and thus wheat yield shall be affect...The solar radiation intensity and duration are continuously decreasing in the major wheat planting area of China. As a con- sequence, leaf senescence, photosynthesis, grain filling and thus wheat yield shall be affected by light deficiency. Therefore, two winter wheat (Triticum aestivum L.) cultivars, Tainong 18 (a large-spike cultivar) and Ji'nan 17 (a multiple-spike cultivar), were subjected to shading during anthesis and maturity under field condition in 2010-2011 and 2011-2012. Under the slight shading treatment ($1,88% of full sunshine), leaf senescence was delayed, net photosynthesis rate (Po) and canopy apparent photosynthesis rate (CAP) were improved, and thus thousand-kernel weight (TKW) and grain yield were higher as compared with the control. However, mid and severe shading (S2 andS3, 67 and 35% of full sunshine, respectively) led to negative effects on these traits substantially. Moreover, superoxide dismutase (SOD), peroxidase (POD) and cat- alase (CAT) activities in flag leaf were significantly greater under slight shading than those in other treatments, while the malondialdehyde (MDA) content was less than that under other treatments. In addition, the multiple-spike cultivar is more tolerant to shading than large-spike cultivar. In conclusion, slight shading after anthesis delayed leaf senescence, enhanced photosynthesis and grain filling, and thus resulted in higher grain yield.展开更多
Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, ...Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, biological hydrogen sulfide removal processes are being investigated to overcome the chemical and disposal costs associated with existing chemically based removal processes. The nitrogen and sulfur metabolism interacts at various levels of the wastewater treatment process. Hence, the sulfur cycle offers possibilities to integrate nitrogen removal in the treatment process, which needs to be further optimized by appropriate design of the reactor configuration, optimization of performance parameters, retention of biomass and optimization of biomass growth. The present paper reviews the biotechnological advances to remove sulfides from various environments.展开更多
Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory condition. The degradation half-live of chlorpyrifos at levels o...Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory condition. The degradation half-live of chlorpyrifos at levels of 4, 8, and 12 mg/kg in soil were calculated to be 14.3, 16.7, and 18.0 d, respectively. The Biolog study showed that the average well color development (AWCD) in soils was significantly (P 〈 0.05) inhibited by chlorpyrifos within the first two weeks and thereafter recovered to a similar level as the control. A similar variation in the diversity indices (Simpson index lID and McIntosh index U) was observed, but no significant difference among the values of the Shannon-Wiener index H' was found in chlorpyrifos-treated soils. With an increasing chlorpyrifos concentration, the half-life of chlorpyrifos was significantly (P ≤ 0.05) extended and its inhibitory effect on soil microorganisms was aggravated. It is concluded that chlorpyrifos residues in soil had a temporary or short-term inhibitory effect on soil microbial functional diversity.展开更多
Eleven evaluating parameters for rice core collection were assessed based on genotypic values and molecular marke' information. Monte Carlo simulation combined with mixed linear model was used to eliminate the interf...Eleven evaluating parameters for rice core collection were assessed based on genotypic values and molecular marke' information. Monte Carlo simulation combined with mixed linear model was used to eliminate the interference from environment in order to draw more reliable results. The coincidence rate of range (CR) was the optimal parameter. Mean Simpson index (MD), mean Shannon-Weaver index of genetic diversity (M1) and mean polymorphism information content (MPIC) were important evaluating parameters. The variable rate of coefficient of variation (VR) could act as an important reference parameter for evaluating the variation degree of core collection. Percentage of polymorphic loci (p) could be used as a determination parameter for the size of core collection. Mean difference percentage (MD) was a determination parameter for the reliability judgment of core collection. The effective evaluating parameters for core collection selected in the research could be used as criteria for sampling percentage in different plant germplasm populations.展开更多
An incubation experiment with soil water content treatments of 0.15 (W1), 0.20 (W2), and 0.40 (W3) g g^-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, ...An incubation experiment with soil water content treatments of 0.15 (W1), 0.20 (W2), and 0.40 (W3) g g^-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, P, and S cycling in a paddy soil from the Taihu Lake region, China, under waterlogged and aerobic conditions. Compared with air-dried soil, waterlogging resulted in a significant decrease (P ≤ 0.05) of fluorescein diacetate (FDA) and /3-D-glucosidase activities, and this effect was enhanced with increasing waterlogging time. Waterlogging also significantly inhibited (P ≤ 0.05) arylsulfatase as well as alkaline and acid phosphatase activities, but did not decrease the activities with the increase in waterlogging time. Short-term waterlogging did not affect urease activity, but prolonged waterlogging decreased it markedly. In contrast, the aerobic incubation (W1 and W2 treatments) significantly increased (P ≤ 0.05) FDA, alkaline phosphatase, and /3-D-glucosidase activities. With aerobic treatments the activities of FDA and alkaline phosphatase increased with incubation time, whereas /3-D-glucosidase activity decreased. A significant difference (P ≤ 0.05) was usually observed between the W1 and W2 treatments for the activities of FDA as well as alkaline and acid phosphatase; however,/3-D-glucosidase and urease were usually not significant (P ≤ 0.05). No activity differences were observed between waterlogging and aerobic incubation for arylsulfatase and urease.展开更多
Blue and red lights differently regulate leaf photosynthesis. Previous studies indicated that plants under blue light generally exhibit better photosynthetic characteristics than those under red light. However, the re...Blue and red lights differently regulate leaf photosynthesis. Previous studies indicated that plants under blue light generally exhibit better photosynthetic characteristics than those under red light. However, the regulation mechanism of related photosynthesis characteristics remains largely unclear. Here, four light qualities treatments (300 μmol m-2 s-1) including white fluorescent light (FL), blue monochromatic light (B, 440 nm), red monochromatic light (R, 660 nm), and a combination of red and blue light (RB, R:B=8:1) were carried out to investigate their effects on the activity of photosystem II (PSII) and photosystem I (PSI), and photosynthetic electron transport capacity in the leaves of cucumber (Cucumis sativus L.) seedlings. The results showed that compared to the FL treatment, the R treatment significantly limited electron transport rate in PSII (ETR11) and in PSI (ETR1) by 79.4 and 66.3%, respectively, increased non-light induced non-photochemical quenching in PSII (q^No) and limitation of donor side in PSI (φND) and reduced most JIP-test parameters, suggesting that the R treatment induced suboptimal activity of photosystems and inhibited electron transport from PSII donor side up to PSI. However, these suppressions were effectively alleviated by blue light addition (RB). Compared with the R treatment, the RB treatment significantly increased ETR, and ETR1 by 176.9 and 127.0%, respectively, promoted photosystems activity and enhanced linear electron transport by elevating electron transport from QA to PSI. The B treatment plants exhibited normal photosystems activity and photosynthetic electron transport capacity similar to that of the FL treatment. It was concluded that blue light is more essential than red light for normal photosynthesis by mediating photosystems activity and photosynthetic electron transport capacity.展开更多
基金financially supported by the National Natural Science Foundation of China (Grant Nos.32101571,32002071)the Zhejiang Science and Technology Major Program on Agricultural New Variety Breeding (Grant No.2021C02071-6)。
文摘Lily(Lilium spp.) is an important ornamental flower, which is mainly propagated by bulbs. Cell wall invertases(CWINs), which catalyze the irreversibly conversion of sucrose into glucose and fructose in the extracellular space, are key enzymes participating in sucrose allocation in higher plants. Previous studies have shown that CWINs play an essential role in bulblet initiation process in bulbous crops, but the underlying molecular mechanism remains unclear. Here, a CWIN gene of Lilium brownii var. giganteum(Lbg) was identified and amplified from genomic DNA. Quantitative RT-PCR assays revealed that the expression level of LbgCWIN1 was highly upregulated exactly when the endogenous starch degraded in non-sucrose medium during in vitro bulblet initiation in Lbg. Phylogenetic relationship, motif, and domain analysis of LbgCWIN1 protein and CWINs in other plant species showed that all sequences of these CWIN proteins were highly conserved. The promoter sequence of LbgCWIN1 possessed a number of alpha-amylase-, phytohormone-, light-and stress-responsive cis-elements. Meanwhile, β-glucuronidase(GUS) assay showed that the 459 bp upstream fragment from the translational start site displayed maximal promoter activity. These results revealed that LbgCWIN1 might function in the process of in vitro bulblet initiation and be in the response to degradation of endogenous starch.
基金financially supported by the National Natural Science Foundation of China(Grant No.U20A2032)the Agro ST Project(Grant No.NK2022050102)the Hainan Provincial Natural Science Foundation,China(Grant No.323MS066)。
文摘Rice cooking and eating qualities(CEQ)are mainly determined by cooked rice textural parameters and starch physicochemical properties.However,the genetic bases of grain texture and starch properties in rice have not been fully understood.We conducted a genome-wide association study for apparent amylose content(AAC),starch pasting viscosities,and cooked rice textural parameters using 279 indica rice accessions from the 3000 Rice Genome Project.We identified 26 QTLs in the whole population and detected single nucleotide polymorphisms(SNPs)with the lowest P-value at the Waxy(Wx)locus for all traits except pasting temperature and cohesiveness.Additionally,we detected significant SNPs at the SUBSTANDARD STARCH GRAIN6(SSG6)locus for AAC,setback(SB),hardness,adhesiveness,chewiness(CHEW),gumminess(GUM),and resilience.We subsequently divided the population using a SNP adjacent to the Waxy locus,and identified 23 QTLs and 12 QTLs in two sub-panels,WxT and WxA,respectively.In these sub-panels,SSG6 was also identified to be associated with pasting parameters,including peak viscosity,hot paste viscosity,cold paste viscosity,and consistency viscosity.Furthermore,a candidate gene encoding monosaccharide transporter 5(OsMST5)was identified to be associated with AAC,breakdown,SB,CHEW,and GUM.In total,39 QTLs were co-localized with known genes or previously reported QTLs.These identified genes and QTLs provide valuable information for genetic manipulation to improve rice CEQ.
基金National Key Technology R&D Program of China(2022YFF1001403)National Science Foundation of China(32101764).
文摘Cotton has enormous economic potential,providing high-quality protein,oil,and fibre.But the comprehensive utilization of cottonseed is limited by the presence of pigment gland and its inclusion.Pigment gland is a common characteristic of Gossypium genus and its relatives,appearing as visible dark opaque dots in most tissues and organs of cotton plants.Secondary metabolites,such as gossypol,synthesized and stored in the cavities of pigment glands act as natural phytoalexins,but are toxic to humans and other monogastric animals.However,only a few cotton genes have been identified as being associated with pigment gland morphogenesis to date,and the developmental processes and regulatory mechanism involved in pigment gland formation remain largely unclear.Here,the research progress on the process of pigment gland morphogenesis and the genetic basis of cotton pigment glands is reviewed,for providing a theoretical basis for cultivating cotton with the ideal pigment gland trait.
基金Supported by Key Laboratory Open Platform Project of Hunan Provincial Department of Education(16K047)Hunan Science and Technology Progject(2023NK 4289)。
文摘[Objectives] This study was conducted to investigate the scientific prevention and control of Solanum nigrum L. [Methods] Through experiments on S. nigrum from different sources, it was found that glyphosate stress had significant effects on antioxidant enzyme activity and oxidative damage of sensitive S. nigrum plants. [Results] Sensitive S. nigrum showed oxidative damage under glyphosate stress, while resistant S. nigrum responded to adversity damage by improving its antioxidant enzyme activity. The experimental results showed that the antioxidant enzymes and reduced glutathione of S. nigrum had certain metabolic detoxification effects under glyphosate stress. [Conclusions] This study provides a theoretical basis for scientific prevention and control of S. nigrum , and has a certain reference value for revealing the glyphosate resistance mechanism of S. nigrum .
基金the National Key R&D Program of China(2018YFD1000706)the Key Research Project of Science and Technology Department of Zhejiang Province,China(2021C02064-3)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China.
文摘Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological and molecular regulation of tillering has been intensively studied in rice and wheat.However,tillering research on barley is scarce.This review used the recent advances in bioinformatics to map all known and potential barley tiller development genes with their chromosomal genetic and physical positions.Many of them were mapped for the first time.We also discussed tillering regulation at genetic,physiological,and environmental levels.Moreover,we established a novel link between the genetic control of phytohormones and sugars with tillering.We provided evidence of how environmental cues and cropping systems help optimize the tiller number.This comprehensive review enhances the understanding of barley’s physiological and genetic mechanisms controlling tillering and other developmental traits.
基金supported by the National Natural Science Foundation of China(Grant No.32101763)China National Postdoctoral Program for Innovative Talents(Grant No.BX2021266)China Postdoctoral Science Foundation(Grant No.2021M692853).
文摘As the‘Green Revolution’gene,SD1(encoding GA20ox2),has been widely applied to improve yield in rice breeding.However,research on its transcriptional regulation is limited.Here,we identified a transcription factor OsbZIP01,which can suppress the expression of SD1 and regulate gibberellin(GA)biosynthesis in rice.Knockout mutants of OsbZIP01 exhibited increased plant height,while the overexpression lines showed a semi-dwarf phenotype and diminished germination rate.Furthermore,the semi-dwarf phenotype of OE-bZIP01,was caused by the reduced internode length,which was accompanied by a thin stem width.The predominant expression of OsbZIP01 was observed in leaves and sheaths.OsbZIP01 protein was localized in the nucleus and showed transcriptional repression activity.In addition,OsbZIP01 could directly bind to the promoter of the OsSD1 gene,and inhibit its transcription.The semi-dwarf phenotype of OE-bZIP01 could be rescued by exogenous GA_(3).Meanwhile,the bzip01 sd1 double mutant showed a shorter shoot length compared with the wild type,indicating that OsbZIP01 regulated plant growth mainly through the GA biosynthesis pathway.Collectively,OsbZIP01 negatively regulates GA biosynthesis by restraining SD1 transcription,thereby affecting plant growth and development.
基金the financial support of the National Natural Science Foundation of China (32060454, 32272109)Hainan Yazhou Bay Seed Laboratory (B21HJ0215)+1 种基金National Natural Science Foundation of China (32072048, U2004204)Specific Research Fund of The Innovation Platform for Academicians of Hainan Province。
文摘Lesion mimic mutants(LMMs) are advantageous materials for studying programmed cell death(PCD).Although some rice LMM genes have been cloned, the diversity of functions of these genes indicates that the mechanism of cell death regulation in LMMs needs further study. In this study, we identified a rice light-dependent leaf lesion mimic mutant 4(llm4) that showed abnormal chloroplast structure, photoinhibition, reduced photosynthetic protein levels, massive accumulation of reactive oxygen species(ROS), and PCD. Map-based cloning and complementation testing revealed that LLM4 encodes zeaxanthin epoxidase(ZEP), an enzyme involved in the xanthophyll cycle, which functions in plant photoprotection,ROS scavenging, and carotenoid and abscisic acid(ABA) biosynthesis. The ABA content was decreased,and the contents of 24 carotenoids differed between the llm4 mutant and the wild type(WT). The llm4mutant showed reduced dormancy and greater sensitive to ABA than the WT. We concluded that the mutation of LLM4 resulted in the failure of xanthophyll cycle, in turn causing ROS accumulation. The excessive ROS accumulation damaged chloroplast structure and induced PCD, leading eventually to the formation of lesion mimics.
基金supported jointly by the Public Project of Science Technology Department of Zhejiang Province(Grant No.2016C02050-9-9)to Y.Jiang and the Zhejiang Provincial Natural Science Foundation of China(Grant No.Y21C130006)to Y.Jiang,and the Key Research and Development Project of Zhejiang Province(Grant No.2021C02057)to G.Luo.
文摘Cultivating salt-tolerant crops is a feasible way to effectively utilize saline-alkali land and solve the problem of underutilization of saline soils.Quinoa,a protein-comprehensive cereal in the plant kingdom,is an exceptional crop in terms of salt stress tolerance level.It seems an excellent model for the exploration of salt-tolerance mechanisms and cultivation of salt-tolerant germplasms.In this study,the seeds and seedlings of the quinoa cultivar Shelly were treated with different concentrations of NaCl solution.The physiological,biochemical characteristics and agronomic traits were investigated,and the response patterns of three salt stress-responsive genes(SSRGs)in quinoa were determined by real-time PCR.The optimum level of stress tolerance of quinoa cultivar Shelly was found in the range of 250–350 mM concentration of NaCl.Salt stress significantly induced expression of superoxide dismutase(SOD),peroxidase(POD),and particularly betaine aldehyde dehydrogenase(BADH).BADH was discovered to be more sensitive to salt stress and played an important role in the salt stress tolerance of quinoa seedlings,particularly at high NaCl concentrations,as it displayed upregulation until 24 h under 100 mM salt treatment.Moreover,it showed upregulation until 12 h under 250 mM salt stress.Taken together,these results suggest that BADH played an essential role in the salt-tolerance mechanism of quinoa.Based on the expression level and prompt response induced by NaCl,we suggest that the BADH can be considered as a molecular marker for screening salt-tolerant quinoa germplasm at the early stages of crop development.Salt treatment at different plant ontogeny or at different concentrations had a significant impact on quinoa growth.Therefore,an appropriate treatment approach needs to be chosen rationally in the process of screening salt-tolerant quinoa germplasm,which is useful to the utilization of saline soils.Our study provides a fundamental information to deepen knowledge of the salt tolerance mechanism of quinoa for the development of salt-tolerant germplasm in crop breeding programs.
基金Supported by Hunan Provincial Postgraduate Education Innovation Project and Professional Ability Improvement Project (CX20211220)Scientific Research Project of Hunan Provincial Department of Education (20A278)+1 种基金Undergraduate Innovation and Entrepreneurship Training Program of Hunan Province (XJT[2021]197,No. 3705)School-level Postgraduate Innovation Experiment Project (24520012)。
文摘[Objectives]This study was conducted to investigate the toxicity of heavy metal antimony(Sb) to ramie(Boehmeria nivea(L.) Gaudich.) and the tolerance response in ramie. [Methods] A pot experiment was conducted to study the effects of Sb stress on root growth and Sb accumulation and transport of the root system of cultivated ramie Zhongzhu No.1, as well as on the physiological characteristics of ramie leaves. [Results] The plant height and root dry weight and volume of Zhongzhu No.1 showed an effect of "promoting at low concentrations and inhibiting at high concentrations" with the increase of Sb concentration, and decreased significantly at the concentration of 4 000 mg/kg, but no obvious toxic growth symptoms were observed. The content of Sb in roots(289.7-508.6 mg/kg) and the root-shoot transfer factor(0.09-0.57) of Zhongzhu No.1 increased with the increase of soil Sb concentration, but the change of Sb bioconcentration factor in roots was opposite, indicating that high concentrations of Sb in soil could promote the absorption of Sb in roots and the transport of Sb to the aboveground part, but the Sb enrichment capacity of roots was relatively reduced with the increase of soil Sb. Sb stress had a certain impact on the physiological characteristics of ramie leaves. With the increase of Sb treatment concentration, MDA, POD and SOD showed a change trend of "first increasing and then decreasing", while CAT gradually increased, indicating that Sb stress caused changes in the physiological characteristics of ramie leaves, thereby affecting plant growth and development. [Conclusions] This study provides a theoretical basis for ecological restoration of ramie in mining areas.
基金Supported by Hunan Provincial University Innovation Platform Open Fund Project(19K049)。
文摘With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.
基金Undergraduate Innovation and Entrepreneurship Training Program of Hunan Province(XJT[2021]197,3705)Scientific Research Project of Education Department of Hunan Province(20A278+1 种基金20B329)Postgraduate Education Innovation Project and Professional Ability Enhancement Project of Hunan Province(CX20211220).
文摘[Objectives] To explore the effects of antimony(Sb) in different valence states on the growth and Sb bioconcentration and transfer of wild ramie(Boehmeria nivea). [Methods] A pot experiment was conducted to study the effects of Sb(Ⅲ) and Sb(Ⅴ) stress on plant height, biomass, leaf SPAD value, Sb contents in various organs, Sb bioconcentration and transfer factors, and other indexes. [Results] Both kinds of Sb treatments showed a trend of "first increasing and then decreasing" in plant height as Sb concentration increased. The plant heights in Sb(Ⅲ) treatments with a concentration lower than 1 000 mg/kg and Sb(Ⅴ) treatments with concentrations lower than 4 000 mg/kg were significantly higher than that of the control check(CK);and the Sb(Ⅲ) treatment of the high concentration(4 000 mg/kg) resulted in a significant decrease in plant height, while the 8 000 mg/kg Sb(Ⅴ) treatment still showed an increase in plant height, indicating that the toxicity of Sb(Ⅴ) to wild ramie was significantly lower than that of Sb(Ⅲ). The Sb(Ⅲ) treatments with a concentration lower than 2 000 mg/kg had little effect on the dry weight of the aboveground part, while the treatment with a higher concentration showed a significant decrease;and the dry weights in various concentrations of Sb(Ⅴ) treatments showed no significant differences, but they were significantly higher than the CK and corresponding concentration of Sb(Ⅲ) treatment. Both types of Sb stress could promote the increase of SPAD value in wild ramie leaves, and the performance was significantly higher than the CK. As the concentration of Sb treatment increased, the Sb content in both the aboveground and underground parts showed a significant increase;and the comparison of Sb content under corresponding concentrations of the two types of Sb treatments showed that in the aboveground part, Sb(Ⅲ) was higher than Sb(Ⅴ), while in the underground part, the opposite was true. The bioconcentration factor(BF) of Sb decreased with the increase of Sb treatment concentration overall, and the value of Sb(Ⅴ) was smaller than that of Sb(Ⅲ), but both kinds of Sb stress were significantly smaller than the CK. The transfer factor(TF) of Sb in wild ramie showed a trend of "increasing first and then decreasing" with the concentration of Sb treatment, and various treatments of Sb(Ⅲ) were higher than the CK, with significant differences, while among various treatments of Sb(Ⅴ), except treatment B3, the reduction of which was not significant, other Sb(Ⅴ) treatments showed significant decreases. Comparing the two types of Sb treatments, the BF and TF values of Sb in wild ramie under Sb(Ⅲ) treatments were higher than those under Sb(Ⅴ) treatments, and the TF reached a significant level, indicating that the Sb transport ability of wild ramie under Sb(Ⅲ) treatments was stronger. [Conclusions] This study provides a theoretical basis for the mining of wild ramie Sb restoration genes and the application of large-scale cultivation in ecological restoration.
基金supported by the Key R&D Program of Yunnan Province,China(Grant No.202103AC100003202101AS070228)+2 种基金the Major Special Project of the Ministry of Science and Technology(2021YFD10002022021YFD1601003)and the National Natural Science Foundation of China(Grant No.31860075),thank you.
文摘Arbuscular mycorrhizal fungi(AMF)are important members of the plant microbiome and affect the uptake and transfer of mineral elements by forming a symbiotic relationship with plant roots.Nitrogen(N),as an important mineral element,can directly affect plant growth and development at different N levels.It has been confirmed that inoculation with AMF can improve the efficiency of N utilization by plants.However,there are still fewer reports on the dynamic relationship between arbuscular mycorrhizal and plant secondary metabolites at different nitrogen levels.In this experiment,the physiological indexes and genes related to saponin synthesis were determined by applying different concentration gradients of nitrogen to the medicinal plant P.polyphylla var.yunnanensis infested by AMF as the test material.It was found that nitrogen addition increased the biomass,chlorophyll content,and nutrient content of above-and below-ground plant parts and increased the content of saponin content of P.polyphylla var.yunnanensis to some extent,but AMF inoculation increased the saponin content of P.polyphylla var.yunnanensis more significantly.AMF inoculation also promoted the expression of genes related to the saponin synthesis pathway,including 3-hydroxy-3-methylglutaryl coenzyme A synthase(HMGS),squalene epoxidase 1(SE1),and cycloartenol synthase(CAS),which is in according with the accumulation of saponin in plants.It also may increase the saponin content of AMF plants by altering the expression of P450s and UGTs related to saponin synthesis.
文摘The growth rate method was adopted to measure the inhibitory effect of curcumin,tetrahydrocurcumin,demethoxycurcumin,and bisdemethoxycurcumin on the mycelial growth of Botrytis cinerea and Colletotrichum gloeosporioides.The results showed that the four curcuminoids inhibited the mycelial growth of the two pathogens in a concentration-dependent manner.Bisdemethoxycurcumin at 600 mg/L exerted the strongest inhibitory effect on the mycelial growth of B.cinerea and C.gloeosporioides,with the relative inhibition rates of 98.19%and 100%,respectively;followed by demethoxycurcumin;curcumin exerted the worst inhibitory effect.Toxicity test results also showed that four curcuminoids all had a certain toxicity to B.cinerea and C.gloeosporioides,among which,bisdemethoxycurcumin exhibited the strongest toxicity,with the EC_(50)of 131.125 and 122.235 mg/L,respectively;while curcumin had the lowest toxicity,with the EC_(50)of 273.143 and 194.943 mg/L,respectively.
文摘In practice, pesticides are usually applied simultaneously or one after another for crop protection, and this type of pesticide application often leads to a combined contamination of pesticide residues in the soil environment. A laboratory study was conducted to investigate the influence of chlorothalonil on chlorpyrifos degradation and its effects on soil bacterial, fungal, and actinomycete populations. Under the experimental conditions here, the half-lives of chlorpyrifos alone, and in combination with chlorothalonil, at the recommended and double dosages, were measured to be 3.24, 2.77, and 2.63 d, respectively. Chlorpyrifos degradation was not significantly altered by its combination with chlorothalonil. However, the inhibitory effect of chlorpyrifos on soil microorganisms was increased by its combination with chlorothalonil, and the increase was related to the levels of chlorothalonil added. Compared to those in the controls, the populations of bacteria, fungi, and actinomycetes were significantly reduced by 44.1%, 61.1%, and 72.8%, respectively, on the first day after treatment (DAT) by chlorpyrifos alone. With the addition of chlorothalonil, the inhibition was increased to 55.2%, 79.3%, and 85,8% at the recommended dosage, and 86.0%, 94.1%, and 90.8% at the double dosage, at one DAT, respectively. The results suggested that combined effects should be taken into account to assess the actual impacts of pesticide applications.
基金supported by the National Natural Science Foundation of China (31271661)the Special Fund for Agro-scientific Research in the Public Interest of China (201203100, 201203031)
文摘The solar radiation intensity and duration are continuously decreasing in the major wheat planting area of China. As a con- sequence, leaf senescence, photosynthesis, grain filling and thus wheat yield shall be affected by light deficiency. Therefore, two winter wheat (Triticum aestivum L.) cultivars, Tainong 18 (a large-spike cultivar) and Ji'nan 17 (a multiple-spike cultivar), were subjected to shading during anthesis and maturity under field condition in 2010-2011 and 2011-2012. Under the slight shading treatment ($1,88% of full sunshine), leaf senescence was delayed, net photosynthesis rate (Po) and canopy apparent photosynthesis rate (CAP) were improved, and thus thousand-kernel weight (TKW) and grain yield were higher as compared with the control. However, mid and severe shading (S2 andS3, 67 and 35% of full sunshine, respectively) led to negative effects on these traits substantially. Moreover, superoxide dismutase (SOD), peroxidase (POD) and cat- alase (CAT) activities in flag leaf were significantly greater under slight shading than those in other treatments, while the malondialdehyde (MDA) content was less than that under other treatments. In addition, the multiple-spike cultivar is more tolerant to shading than large-spike cultivar. In conclusion, slight shading after anthesis delayed leaf senescence, enhanced photosynthesis and grain filling, and thus resulted in higher grain yield.
基金Project supported by the National Natural Science Foundation ofChina (No. 30070017)the Science and Technology Foundationfor Key Project of Zhejiang Province (No. 2003C13005), China
文摘Sulfide-containing waste streams are generated by a number of industries. It is emitted into the environment as dis- solved sulfide (S2- and HS-) in wastewaters and as H2S in waste gases. Due to its corrosive nature, biological hydrogen sulfide removal processes are being investigated to overcome the chemical and disposal costs associated with existing chemically based removal processes. The nitrogen and sulfur metabolism interacts at various levels of the wastewater treatment process. Hence, the sulfur cycle offers possibilities to integrate nitrogen removal in the treatment process, which needs to be further optimized by appropriate design of the reactor configuration, optimization of performance parameters, retention of biomass and optimization of biomass growth. The present paper reviews the biotechnological advances to remove sulfides from various environments.
基金supported by the National Hi-Tech Research and Development Program (863) of China (No.2006AA06Z386, 2007AA06Z306)the China Postdoctor-al Science Foundation (No. 20070421174)+2 种基金the National Natural Science Foundation of China (No. 30771254)the Zhejiang Provincial Natural Science Foundation (No.Z306260)the National Key Technologies R&D Pro-gram of China (No. 2006BAI09B03)
文摘Degradation of chlorpyrifos at different concentrations in soil and its impact on soil microbial functional diversity were investigated under laboratory condition. The degradation half-live of chlorpyrifos at levels of 4, 8, and 12 mg/kg in soil were calculated to be 14.3, 16.7, and 18.0 d, respectively. The Biolog study showed that the average well color development (AWCD) in soils was significantly (P 〈 0.05) inhibited by chlorpyrifos within the first two weeks and thereafter recovered to a similar level as the control. A similar variation in the diversity indices (Simpson index lID and McIntosh index U) was observed, but no significant difference among the values of the Shannon-Wiener index H' was found in chlorpyrifos-treated soils. With an increasing chlorpyrifos concentration, the half-life of chlorpyrifos was significantly (P ≤ 0.05) extended and its inhibitory effect on soil microorganisms was aggravated. It is concluded that chlorpyrifos residues in soil had a temporary or short-term inhibitory effect on soil microbial functional diversity.
基金the National Natural Science Foundation of China (Grant No. 30270759) the Science and Technology Department of Zhejiang Province (Grant No. 2005C32001).
文摘Eleven evaluating parameters for rice core collection were assessed based on genotypic values and molecular marke' information. Monte Carlo simulation combined with mixed linear model was used to eliminate the interference from environment in order to draw more reliable results. The coincidence rate of range (CR) was the optimal parameter. Mean Simpson index (MD), mean Shannon-Weaver index of genetic diversity (M1) and mean polymorphism information content (MPIC) were important evaluating parameters. The variable rate of coefficient of variation (VR) could act as an important reference parameter for evaluating the variation degree of core collection. Percentage of polymorphic loci (p) could be used as a determination parameter for the size of core collection. Mean difference percentage (MD) was a determination parameter for the reliability judgment of core collection. The effective evaluating parameters for core collection selected in the research could be used as criteria for sampling percentage in different plant germplasm populations.
基金Project supported by the National Basic Research Program of China (No. G1999011808) and the National Natural Science Foundation of China (No. 40371066).
文摘An incubation experiment with soil water content treatments of 0.15 (W1), 0.20 (W2), and 0.40 (W3) g g^-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, P, and S cycling in a paddy soil from the Taihu Lake region, China, under waterlogged and aerobic conditions. Compared with air-dried soil, waterlogging resulted in a significant decrease (P ≤ 0.05) of fluorescein diacetate (FDA) and /3-D-glucosidase activities, and this effect was enhanced with increasing waterlogging time. Waterlogging also significantly inhibited (P ≤ 0.05) arylsulfatase as well as alkaline and acid phosphatase activities, but did not decrease the activities with the increase in waterlogging time. Short-term waterlogging did not affect urease activity, but prolonged waterlogging decreased it markedly. In contrast, the aerobic incubation (W1 and W2 treatments) significantly increased (P ≤ 0.05) FDA, alkaline phosphatase, and /3-D-glucosidase activities. With aerobic treatments the activities of FDA and alkaline phosphatase increased with incubation time, whereas /3-D-glucosidase activity decreased. A significant difference (P ≤ 0.05) was usually observed between the W1 and W2 treatments for the activities of FDA as well as alkaline and acid phosphatase; however,/3-D-glucosidase and urease were usually not significant (P ≤ 0.05). No activity differences were observed between waterlogging and aerobic incubation for arylsulfatase and urease.
基金supported by the Special Fund for Nonprofit Industry (Agriculture) Research Project (201303014)Earmarked Fund for Beijing Fruit Vegetable Innovation Team Project of Modern Agro-industry Technology Research System (GCTDZJ2014033007) in China
文摘Blue and red lights differently regulate leaf photosynthesis. Previous studies indicated that plants under blue light generally exhibit better photosynthetic characteristics than those under red light. However, the regulation mechanism of related photosynthesis characteristics remains largely unclear. Here, four light qualities treatments (300 μmol m-2 s-1) including white fluorescent light (FL), blue monochromatic light (B, 440 nm), red monochromatic light (R, 660 nm), and a combination of red and blue light (RB, R:B=8:1) were carried out to investigate their effects on the activity of photosystem II (PSII) and photosystem I (PSI), and photosynthetic electron transport capacity in the leaves of cucumber (Cucumis sativus L.) seedlings. The results showed that compared to the FL treatment, the R treatment significantly limited electron transport rate in PSII (ETR11) and in PSI (ETR1) by 79.4 and 66.3%, respectively, increased non-light induced non-photochemical quenching in PSII (q^No) and limitation of donor side in PSI (φND) and reduced most JIP-test parameters, suggesting that the R treatment induced suboptimal activity of photosystems and inhibited electron transport from PSII donor side up to PSI. However, these suppressions were effectively alleviated by blue light addition (RB). Compared with the R treatment, the RB treatment significantly increased ETR, and ETR1 by 176.9 and 127.0%, respectively, promoted photosystems activity and enhanced linear electron transport by elevating electron transport from QA to PSI. The B treatment plants exhibited normal photosystems activity and photosynthetic electron transport capacity similar to that of the FL treatment. It was concluded that blue light is more essential than red light for normal photosynthesis by mediating photosystems activity and photosynthetic electron transport capacity.