首页期刊导航|Environmental and experimental botany
期刊信息/Journal information
Environmental and experimental botany
Pergamon Press,
Environmental and experimental botany

Pergamon Press,

0098-8472

Environmental and experimental botany/Journal Environmental and experimental botanySCIISTP
正式出版
收录年代

    Ultraviolet-B-induced MdWRKY71-L expression regulates anthocyanin synthesis in apple

    Li C.Li B.Su M.Wang S....
    10页
    查看更多>>摘要：? 2022 Elsevier B.V.Anthocyanin plays critical role in plant secondary metabolism. Although many transcription factors (TFs) that participate in the anthocyanin biosynthesis pathway have been characterized, many have yet to be reported. In the study, we cloned a WRKY Group IIc TF in apple (Malus × domestica), MdWRKY71-L, which localized to the nucleus. The overexpression of MdWRKY71-L promoted the accumulation of anthocyanin in apple calli. MdWRKY71-L mainly stimulated this accumulation through interacting with the promoters of MdMYB1 and MdUFGT. In addition to plant genotype, the synthesis of anthocyanin is also affected by external factors, such as ultraviolet-B radiation. Ultraviolet-B exposure induced MdWRKY71-L expression and MdWRKY71-L promoted the expression of MdHY5 by interacting with its promoter. Our research provided new insights into how WRKY TFs participated in the ultraviolet-B signaling pathway to regulate the accumulation of anthocyanin in apple.
      原文链接:
    • NSTL
    • Elsevier

    Iterative analysis of metabolic modulation in the cyanobacterium Aphanizomenon flos-aquae 2012 KM1/D3 upon nitric oxide synthase derived NO induction

    Gupta N.Mishra A.K.
    14页
    查看更多>>摘要：? 2022 Elsevier B.V.Nitric oxide synthase (NOS) in mammals is recognized for its essentialities in several metabolism including blood vascular relaxation and nerves transmission etc. yet their functionalities in prokaryotes are largely unknown. Our study aimed to evaluate the putative role of nitric oxide synthase (NOS) derived nitric oxide (NO) during oxidative burst in the cyanobacterium, Aphanizomenon flos-aquae 2012/KM1/D3. Here, the accumulation of NO was dramatically reduced upon NOS inhibitor L-NG-Nitro arginine methyl ester (L-NAME) supplementation, exhibiting significant NO synthesis by NOS, whereas addition of L-arginine increase NOS derived NO in a dose dependent manner. Moreover, the reduction in the growth and metabolic activities of the cyanobacterium were evident upon L-NAME treatment that possibly pertained to decline in photopigments, PSII efficiency, loss in membrane integrity and DNA damage due to oxidative burst which culminated into cell death. Besides, the increment in carbohydrates and lipid content ensued with a decrease in protein content, indicating gluconeogenesis. Additionally, NOS inhibition disrupted the fatty acid and hydrocarbon profile, suggesting diminished membrane fluidity and cell integrity. However, higher content of flavonoids, phenolics, thiols and proline in L-NAME treated cells was also observed. Furthermore, L-arginine supplementation enhanced pigment content, photosynthetic efficiency, and reduced oxidative stress, thereby enhancing cyanobacterial growth. Further, L-arginine supplementation maintained Asc/DHAsc and GSH/GSSG ratio, conferred redox homeostasis. These results suggest that the NOS activity plays a critical role in protecting cyanobacteria from oxidative burst, maintaining their physiological balance.
      原文链接:
    • NSTL
    • Elsevier

    Limited mitigating effects of elevated CO2 in young aspen trees to face drought stress

    Lauriks F.Salomon R.L.De Roo L.Rodriguez-Garcia A....
    11页
    查看更多>>摘要：? 2022 Elsevier B.V.Elevated atmospheric CO2 concentration (eCO2) is expected to mitigate the adverse effects of moderate drought on leaf and whole-tree functioning. However, tree responses to eCO2 under severe drought and throughout the growing season remain largely unknown. One-year-old Populus tremula L. trees were grown in two controlled treatment chambers under ambient and elevated CO2 conditions, while progressive drought was imposed early (spring/summer 2019) and late (summer/autumn 2018) during the growing season. Leaf level responses to eCO2 (i.e., stomatal conductance, leaf carbon assimilation and leaf respiration) were monitored in concert with whole-tree level responses (i.e., canopy conductance, radial stem growth, stem CO2 efflux, xylem water potential and non-structural carbohydrates (NSC)). At the leaf level, eCO2 lowered the drought susceptibility of stomatal closure and delayed drought-induced reduction in leaf carbon assimilation during late season drought, but these responses were not observed during the early season drought. Drought effects on whole-tree functioning and NSC depletion remained unaltered by eCO2. Under moderate drought, stem volumetric growth ceased earlier than photosynthesis, while leaf and stem respiratory metabolism were maintained at 30 % of well-watered levels even under severe drought, independent of the CO2 treatment and timing of drought. Therefore, the ability of eCO2 to mitigate drought was mainly limited to leaf processes during the late season and under moderate drought (> ? 2 MPa), while drought offset any beneficial effect of eCO2 at the whole-tree level. These results urge us to revisit predictions of forests' potential to sequester carbon under climate change scenarios.
      原文链接:
    • NSTL
    • Elsevier

    Genome wide association study and haplotype analysis reveals the role of HvHKT1;5 in potassium retention but not Na+ exclusion in barley (Hordeum vulgare L.)

    Zhu J.Guo Y.Zhou H.Hong Y....
    10页
    查看更多>>摘要：? 2022 Elsevier B.V.Salinity stress is one of the major abiotic stresses which affect grain yield and quality in crops. Identifying and exploring the QTL/genes and elite alleles that control salt tolerance is crucial for breeding salt-tolerant crop varieties. In this study, a diverse panel of 214 barley (Hordeum vulgare L.) accessions were used to identify quantitative trait loci (QTL) for salt tolerance and Na+ and K+ content in leaves under salt stress by MLM model and MapQTL6.0 software. Significant correlations between leaf ion content and salt tolerance were observed. One major QTL, Q.SL.2H, was identified on chromosome 2H and was responsible for the overall salinity tolerance through regulating Na+ exclusion under salt stress. The other major QTL was detected on chromosome 4H that overlapped with HvHKT1;5 gene and was responsible for K+ retention in leaves. Several other minor QTL were detected by MapQTL that could help in selecting salt-tolerant varieties. The haplotype analysis showed that amino acid substitutions of HvHKT1;5 in exon2 at 416 and 438 may have contributed to K+ retention under salinity stress. These findings indicate the existence of two major mechanisms for salinity tolerance determined by two major QTL and challenge the accepted views on the role of HvHKT1;5 transporters in Na+ exclusion in barley adaptive response to salinity stress.
      原文链接:
    • NSTL
    • Elsevier

    The in vivo performance of a heat shock transcription factor from Populus euphratica, PeHSFA2, promises a prospective strategy to alleviate heat stress damage in poplar

    Li H.-G.Yang Y.Liu M.Zhu Y....
    14页
    查看更多>>摘要：? 2022 Elsevier B.V.Heat stress driven by global warming has affected forest yields and survival at a larger scale in recent decades, hence breeding heat-tolerant tree species has become imperative. We here investigated the role of PeHSFA2, a crucial gene in plant heat shock response from Populus euphratica, in regulating plant heat stress protection. PeHSFA2 is localized to the cytoplasm and nucleus and can be transported from the cytoplasm into the nucleus under detrimental high-temperature conditions. Poplar plants with overexpressed PeHSFA2 outperformed the control group when subjected to severe heat stress, for they had higher leaf water content, lower leaf relative electrolyte leakage, and better photosynthetic activity after heat treatment. The results of qRT-PCR analyses revealed that PeHSFA2 regulates the transcription of a group of heat-protective genes including small heat shock protein, GALACTINOL SYNTHASE 2.2, and ASCORBATE PEROXIDASE 2 in white poplar. Transactivation assays confirmed that PeHSFA2 activated the expression of PtoHSP19.9, PtoHSP21.3, PtoHSP21.8, PtoHSP22.0, PtoGOLS2.2, and PtoAPX2 via binding to the promoter regions of these genes. These results emphasize the point that PeHSFA2 can vehemently reinforce plant thermotolerance via regulating the transcription of a set of heat shock response genes, and PeHSFA2 possesses enormous potential in breeding poplar plants with substantially enhanced thermotolerance.
      原文链接:
    • NSTL
    • Elsevier

    Halotolerant plant growth-promoting rhizobacteria-mediated alleviation of salinity and dust stress and improvement of forage yield in the desert halophyte Seidlitzia rosmarinus

    Zilaie M.N.Arani A.M.Etessami H.Dinarvand M....
    18页
    查看更多>>摘要：? 2022 Elsevier B.V.In desert areas, a set of environmental stresses such as salinity and dust simultaneously affect plant biomass and nutritional value. In this study, the effects of two halotolerant plant growth-promoting rhizobacterial strains, Bacillus pumilus HR, isolated from the halophyte Halostachys belangeriana, and Zhihengliuella halotolerans SB, isolated from the halophyte Seidlitzia rosmarinus, on morpho-physiological, biochemical and ionomic properties of S. rosmarinus under salinity stress (0, 300, and 600 mM NaCl) and mineral dust (0 and 1.5 g m?2 month?1) were examined. Salinity stress reduced the morpho-physiological characteristics of S. rosmarinus plant more than dust stress. The dust application, similar to salinity stress, increased the content of Na, malondialdehyde (MDA), acidity, and glycine betaine in S. rosmarinus leaves. Z. halotolerans SB strain was more effective than B. pumilus HR strain in improving the characteristics of S. rosmarinus under salinity and dust stress. Under the conditions of combined application of salinity (at 600 mM NaCl level) and dust stress, this strain (SB) increased chlorophyll a content by 40%, protein content by 48%, Fe content by 45%, Mg content by 63%, Mn content by 21%, total dry biomass by 35%, seedling quality index by 104%, catalase activity by 47%, anthocyanin content by 85, and Na content by 53% in S. rosmarinus plant leaves compared to control. In addition, the results of PCA analysis showed that at salinity level of 300 and 600 mM NaCl, there were an increase in antioxidant indices and a sharp increase in Na and MDA content in S. rosmarinus leaves, respectively. It was also suggested that the bacterial strain (Z. halotolerans SB) can increase the quantity and quality of forage (seedling quality index) better than another bacterial strain (B. pumilus HR) under salinity and dust conditions. In general, the study reveals that the application of halotolerant rhizobacteria can be a cost effective and ecological sustainable method to improve the yield and quality of forage in the desert halophyte S. rosmarinus under salinity and dust stress conditions.
      原文链接:
    • NSTL
    • Elsevier

    Effects of nitrogen application after abrupt drought-flood alternation on rice root nitrogen uptake and rhizosphere soil microbial diversity

    Tang G.Zhu J.Li A.Zhang J....
    9页
    查看更多>>摘要：? 2022 Elsevier B.V.Abrupt drought-flood alternation is a frequent meteorological disaster that occurs during the summer in southern China. This study sought to clarify the composition of the bacterial community in the rhizosphere soil of rice under nitrogen (N) application after abrupt drought-flood alternation and to provide more basic data for understanding N absorption by the roots system under N application after abrupt drought-flood alternation. The activity of N metabolism enzymes and the N content and N accumulation in various organs improved under N application after abrupt drought-flood alternation. Between the T1_N and T1 comparison groups, 1758 differentially expressed genes were identified, including 1027 upregulated and 731 downregulated genes. Transcriptomic GO and KEGG analyses indicated that nitrate assimilation, response to bacterium, defence response to bacterium, and N compound metabolic processes were enriched. At the phylum level, Proteobacteria, Acidobacteria, Nitrospirota, and Gemmatimonadota were the dominant flora. The root glutamine synthetase activity was significantly negatively correlated with Nitrospirota. Nitrospirota is a key taxon regulating rice root N absorption under N application after abrupt drought-flood alternation. N application after abrupt drought-flood alternation promoted the rapid recovery ability of plants and improved the microbial environment in rice. This study preliminarily clarified the role of microorganisms in the root uptake of rice under N application after abrupt drought-flood alternation.
      原文链接:
    • NSTL
    • Elsevier

    Brassinosteroids promote starch synthesis and the implication in low-light stress tolerance in Solanum lycopersicum

    Liu Y.Wei J.Yu J.Xia X....
    11页
    查看更多>>摘要：? 2022 Elsevier B.V.Starch, as the stored form of carbohydrates in plants, can be degraded into soluble sugars to meet the needs of metabolism when photosynthesis is closed. However, the role of starch synthesis in response to prolonged low light stress in greenhouse crops is unclear. In this study, we found that overexpression of brassinosteroids (BRs) synthesis gene DWARF (DWF) increased accumulation of starch and soluble sugars in tomato leaves, whereas BRs deficient mutant dwf exhibited the opposite changes. The expressions of genes encoding the starch synthesis enzymes such as granule bound starch synthase (GBSS) and ADP-glucose pyrophosphorylase (AGPase) were significantly enhanced by overexpression of DWF, but decreased in dwf mutant. The enzyme activities of GBSS and AGPase were regulated by BRs in a similar way. Exogenous 24-epibrassinolide (EBR) also increased starch synthesis and promoted plant growth. Furthermore, increasing BRs synthesis or exogenous EBR delayed senescence and enhanced plant performance under prolonged low light stress. Our results demonstrated that BRs-induced low light stress was closely associated with starch synthesis. The study deepened our understanding on the roles of BR in carbohydrate metabolism, and implicated the application of BRs in coping with the low light stress in a context of global climate changes.
      原文链接:
    • NSTL
    • Elsevier

    Different fates and retention of deposited NH4+ and NO3? in an alpine grassland in northwest China: A 15N tracer study

    Wan Q.Liu Y.Xie M.Li L....
    8页
    查看更多>>摘要：? 2022 Elsevier B.V.The fates and redistribution of deposited nitrogen (N) determine the influence on N cycling in terrestrial ecosystems. However, the different fates between deposited nitrate nitrogen (NO3?) and ammonium nitrogen (NH4+) as well as the amount of deposited N retained in ecosystems are still not fully understood. We conducted a field experiment to investigate the fates of deposited NO3? and NH4+ by application of stable 15N isotopes over a period of 455 days in an alpine grassland ecosystem and determined the preference of NO3? and NH4+ for different types of plants. Our research showed that at 15 and 455 days after tracer labeling, the total 15N recovery of NO3? and NH4+ declined from 48.48% to 21.99% and 49.31–7.87%, respectively, indicating that the long-term NH4+-N retention capacity of alpine grassland was lower than NO3?-N. This condition indicated that the changes in deposited N composition can affect the N cycling in ecosystems. Most of N in 15N-NO3? and 15N-NH4+ were immobilized in the litter layer from 22.08% to 9.02% and 36.70–4.53%, respectively, suggesting that the litter layer was the major N sink of NH4+and NO3?. In addition, 19.13% and 2.81% of added 15N-NO3? were recovered in plant, which was twice more than those of 15N-NH4+ (8.43% and 1.42%), indicating that the preference of plants in our study area was NO3?-N. Our results demonstrated the great difference of dynamics in the fate and redistribution of deposition N-NO3? and N-NH4+, about half of atmospherically deposited N-NO3? and N-NH4+ were lost in the initial period, and that mere portion retained within the ecosystem consistently decreased, especially for N-NH4+. Our results also show that the N retention capacity of alpine grassland is relatively weak, resulting in a positively but limited effectiveness in growth and carbon sequestration enhancement. These results can help to assess the ecological effects of N deposition.
      原文链接:
    • NSTL
    • Elsevier

    SIZ1-mediated SUMOylation responds to multiple abiotic stresses in plants

    Fang S.Hou X.Liang X.
    10页
    查看更多>>摘要：? 2022 Elsevier B.V.SUMOylation is an important posttranslational modification of eukaryotes that is widely present in metabolic regulation processes under various stresses. SIZ1 is a SUMO E3 ligase that plays a key role in substrate-specific recognition and directly promotes the binding of SUMO proteins to target proteins. Here, we reviewed the characteristics of SUMO as well as SUMOylation and the role of the SUMO E3 ligase SIZ1 in plant adaptation to abiotic stresses such as abnormal temperature, drought, salinization, phosphorus and nitrogen deficiency, heavy metal and metalloid toxicity, light exposure and reactive oxygen species. This review will enhance our understanding of these stressors and provide a useful reference for appropriate crop improvement, especially in suboptimal environments. Moreover, we provide a reference for future research on the role of SUMOylation in plant responses to abiotic stress.
      原文链接:
    • NSTL
    • Elsevier