Search

The entry of antibiotics, as pollutants, into the environment has created great concerns. Environmental dynamics of antibiotics based on soil chemical properties need to be a better understanding of their chemical behavior. This research is focused on studying the adsorption behavior and kinetic mechanisms of ciprofloxacin (CIP) in an agricultural soil. For this purpose, a batch experiment was conducted at different times (5 min–24 h), and using initial concentrations of CIP (0–1 mmol L−1) in the soil. The adsorption processes as affected by pH and ionic strength were assessed based on the modeling with response surface methodology (RSM). According to the results, the sorption equilibrium was found within 240 min, and the pseudo second-order model was the best for describing the data. Increasing the initial CIP concentration increased CIP adsorption, but increases in ionic strength and pH had an inverse effect. Based on RSM modeling, the CIP adsorption was 7.31 and 7.03 (mg g−1) in the presence of NaCl and CaCl2 electrolytes, respectively, in the optimized conditions (pH 6.5 and ionic strength 0.01 mol L−1). The spontaneous nature of CIP adsorption was determined based on thermodynamic calculations (ΔG° = −10.8 to −12.4 kJ mol−1). The interaction of pH and ionic strength was described with the quadratic model. The obtained results contribute to understanding the CIP fate in the soil environment and facilitate decisions regarding entry and controlling soil contamination due to this antibiotic.

Abstract Melia azedarach demonstrates strong salt tolerance and thrives in harsh saline soil conditions, but the underlying mechanisms are poorly understood. In this study, we analyzed gene expression under low, medium, and high salinity conditions to gain a deeper understanding of adaptation mechanisms of M. azedarach under salt stress. The GO (gene ontology) analysis unveiled a prominent trend: as salt stress intensified, a greater number of differentially expressed genes (DEGs) became enriched in categories related to metabolic processes, catalytic activities, and membrane components. Through the analysis of the category GO:0009651 (response to salt stress), we identified four key candidate genes (CBL7, SAPK10, EDL3, and AKT1) that play a pivotal role in salt stress responses. Furthermore, the KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis revealed that DEGs were significantly enriched in the plant hormone signaling pathways and starch and sucrose metabolism under both medium and high salt exposure in comparison to low salt conditions. Notably, genes involved in JAZ and MYC2 in the jasmonic acid (JA) metabolic pathway were markedly upregulated in response to high salt stress. This study offers valuable insights into the molecular mechanisms underlying M. azedarach salt tolerance and identifies potential candidate genes for enhancing salt tolerance in M. azedarach.

Global food security (GFS) is challenged by increasing food demand due to population growth and climate change. International trade and globalization have underpinned GFS until the most recent public health, geopolitical and economic crises, when virtually overnight, the focus of governments has shifted towards domestically and locally produced foods. However, the agri-food sector has limited flexibility, and relatively long periods are needed for fundamental/sustainable changes. One of the crucial factors enabling GFS is the efficient water management, but the required knowledge and capabilities are often lacking regionally/locally. We propose the Centers for Optimizing Water Management in Agroecosystems as a long-term solution. The Centers would be the specialized hubs for promotion of research, innovation and technology transfer, raising the knowledge of stakeholders (farmers, extension and government officials, scholars, students, policymakers and other professionals) and their capacities in water management. These Centers would operate as research/education/technology demonstration entities tailored to the specifics of a particular country/region, aiming to address the most important and pertinent goals and outcomes with a high-spatial-resolution outreach. Finally, the Centers will improve farmers’ livelihoods, contribute to sustainable and efficient use of agro-environmental resources, and increase productivity and food quality, ultimately supporting GFS.

Abstract Background Titanium dioxide nanoparticles (TiO2 NPs) have been reported to have contrasting effects on plant physiology, while their effects on sugar, protein, and amino acid metabolism are poorly understood. In this work, we evaluated the effects of TiO2 NPs on physiological and agronomical traits of tomato (Solanum lycopersicum L.) seedlings. Tomato seeds were treated with TiO2 NPs (1000 and 2000 mg L− 1), TiO2 microparticles (µPs, 2000 mg L− 1) as the size control, and ultrapure water as negative control. Results The dry matter of stems (DMs), leaves (DMl) and total dry matter (DMt) decreased as particle concentration increased. This trend was also observed in the maximum quantum yield of light-adapted photosystem II (PSII) (Fv´/Fm´), the effective quantum yield of PSII (ΦPSII), and net photosynthesis (Pn). The concentrations of sugars, total soluble proteins, and total free amino acids were unaffected, but there were differences in the daily dynamics of these compounds among the treatments. Conclusion Our results suggest that treating tomato seeds with TiO2 might affect PSII performance, net photosynthesis and decrease biomass production, associated with a concentration- and size-related effect of TiO2 particles.

For centuries, medicinal plants have been used as sources of remedies and treatments for various disorders and diseases. Recently, there has been renewed interest in these plants due to their potential pharmaceutical properties, offering natural alternatives to synthetic drugs. Echinacea, among the world’s most important medicinal plants, possesses immunological, antibacterial, antifungal, and antiviral properties. Nevertheless, there is a notable lack of thorough information regarding the echinacea species, underscoring the vital need for a comprehensive review paper to consolidate existing knowledge. The current review provides a thorough analysis of the existing knowledge on recent advances in understanding the physiology, secondary metabolites, agronomy, and ecology of echinacea plants, focusing on E. purpurea, E. angustifolia, and E. pallida. Pharmacologically advantageous effects of echinacea species on human health, particularly distinguished for its ability to safeguard the nervous system and combat cancer, are discussed. We also highlight challenges in echinacea research and provide insights into diverse approaches to boost the biosynthesis of secondary metabolites of interest in echinacea plants and optimize their large-scale farming. Various academic databases were employed to carry out an extensive literature review of publications from 2001 to 2024. The medicinal properties of echinacea plants are attributed to diverse classes of compounds, including caffeic acid derivatives (CADs), chicoric acid, echinacoside, chlorogenic acid, cynarine, phenolic and flavonoid compounds, polysaccharides, and alkylamides. Numerous critical issues have emerged, including the identification of active metabolites with limited bioavailability, the elucidation of specific molecular signaling pathways or targets linked to echinacoside effects, and the scarcity of robust clinical trials. This raises the overarching question of whether scientific inquiry can effectively contribute to harnessing the potential of natural compounds. A systematic review and analysis are essential to furnish insights and lay the groundwork for future research endeavors focused on the echinacea natural products.

Increasing attention is paid to providing new tools to breeders for targeted breeding for specific root traits that are beneficial in low-fertility, drying soils; however, such information is not available for barley (Hordeum vulgare L.). A panel of 191 barley accessions (originating from Australia, Europe, and Africa) was phenotyped for 26 root and shoot traits using the semi-hydroponic system and genotyped using 21 062 high-quality single nucleotide polymorphism (SNP) markers generated by genotyping-by-sequencing (GBS). The population structure analysis of the barley panel identified six distinct groups. We detected 1199 significant (P

Abstract The availability of phosphorus (P) fertilizer applied to soil can diminish rapidly because of the complex soil P immobilization processes. However, the quantitative distribution of fertilizer P in the soil P fractions is not fully understood. Here, two experiments were conducted in a greenhouse using 32P‐labelled KH2PO4 to (i) quantify the distribution of P fertilizer in soil fractions, microorganisms and maize shoots grown in contrasting soils; (ii) characterize the effect of planting maize on soil P fractions and (iii) determine the amount of plant P derived from fertilizer vs. soil. Depending on the soil type, 74.1%–84.1% of the labelled P was retained in the soil, 11.4%–14.5% was found in maize shoots and 0.7%–4.5% was present in microorganisms. Distribution of applied P in the soil P fractions was dependent on soil type, with most P present as NaOH‐Pi and residual‐P in the Red soil, and as HCl‐P in the Fluvo‐aquic soil. Root‐mediated processes were involved in mobilisation of residual‐P in all three soils, with significant depletion of NaOH‐Pi in the Red soil, NaOH‐Pi and HCl‐P in the Black soil, and HCl‐P in the Fluvo‐aquic soil. The plant P derived from fertilizer and soil increased with increasing P addition rates in all three soils. In the soils with low‐P availability, fertilizer contributed more P to plants than soil, whereas in the initially high‐P soil, the opposite occurred. In conclusion, the partitioning of fertilizer P to various soil P fractions is dependent on the soil type, and the contribution of P derived from fertilizer to maize P uptake was related inversely to the soil legacy P.

Abstract Biochar can significantly change soil properties and improve soil quality. However, the effects of long‐term combined application of biochar (B) and nitrogen (N) fertilizer on relationships between soil enzyme activity, microbial community structure, and crop yield are still obscure. We characterized these relationships in a long‐term (8 years) field experiment with rice, two biochar rates of 0 and 13.5 t ha−1 year−1 (B0 and B) and two N fertilizer rates of 0 and 300 kg N ha−1 year−1 (N0 and N). The repeated, long‐term combined applications of biochar and N fertilizer significantly increased microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN), but biochar decreased the abundance of total bacteria, fungi, actinomycetes, and gram‐positive and gram‐negative bacteria as well as the amount of total phospholipid fatty acids. The activity of leucine aminopeptidase (LAP) decreased significantly in the biochar‐amended and N fertilized treatment, but the LAP activity either remained unchanged or increased with biochar amendment at N0. The relative abundance of bacterial phylum Chloroflexi was increased in the combined biochar and N fertilizer treatment. The changes in soil organic matter and the activity of α‐1,4‐xylosidase were the major properties influencing soil bacterial community composition, whereas the structure of fungal community was governed by MBC, MBN, and LAP activities. In addition, long‐term biochar and N fertilizer applied together significantly increased rice yield (more than biochar and nitrogen fertilizer applied alone). Yield was significantly positively correlated with LAP activity, but significantly negatively correlated with the relative abundance of Chloroflexi. In conclusion, long‐term biochar and nitrogen fertilizer applications increased rice yield, which was associated with altered soil microbial community and enhanced activity of some enzymes.

IntroductionQuince A (Cydonia oblonga Mill.), a typical dwarfing rootstock in pear cultivation, is susceptible to iron (Fe) deficiency in calcareous soils. The aim of this study was to compare the strategies in Fe uptake and utilization in dwarfing rootstock quince A (low Fe efficiency) versus a typical vigorous rootstock Pyrus betulifolia (PB) with high Fe efficiency.MethodsQuince A and PB were grown in nutrient solution (pH 6.3) for 4 weeks followed by three pH treatments: pH6.3, pH8.3a (adjusted with hydroxide) and pH8.3b (adjusted with bicarbonate). The Fe uptake and utilization indicators of the rootstocks were assessed at the onset of chlorosis symptoms (after 58 days of treatments).Results and discussionIn contrast to PB, quince A exhibited Fe deficiency chlorosis under bicarbonate (pH8.3b). Bicarbonate stimulated the root proton secretion, inhibited root growth and ferric chelate reductase (FCR) activity in both PB and quince A, whereas high pH without bicarbonate (pH8.3a) stimulated only root proton release. Both species accumulated more Fe in roots under high pH treatments than under pH6.3, resulting in Fe sufficiency in leaves. Both high pH treatments increased the activity of leaf FCR in PB and quince A. However, extractable Fe(II) concentration in leaves was increased by high pH treatments in PB only. This study demonstrated that depressed Fe(III) reduction in leaves caused by bicarbonate rather than high pH explained Fe deficiency in quince A grown in bicarbonate-containing medium.

The Acer truncatum Bunge, widely distributed in North China, shows excellent tolerance to low-P soils. However, little information is available on potential phosphate-solubilizing bacterial (PSB) strains from the A. truncatum rhizosphere. The objectives of this work were to isolate and characterize PSB from A. truncatum rhizosphere soil and to evaluate the effect of inoculation with the selected strain on A. truncatum seedlings. The strains were characterized on the basis of phenotypic characteristics, carbon source utilization pattern, fatty acid methyl esters analysis, 16S rRNA gene and the whole-genome sequence. A Gram-negative and rod-shaped bacterium, designated MQR6T, showed a high capacity to solubilize phosphate and produce indole-3-acetic acid (IAA) and siderophores. The strain can solubilize tricalcium phosphate (TCP) and rock phosphate (RP), and the solubilization of TCP was about 60% more effective than RP. Phylogenetic analyses based on the 16S rRNA gene and whole-genome sequences revealed that strain MQR6T formed a distinct phyletic lineage as a new species within the genus Pantoea. The digital DNA-DNA hybridization value between strain MQR6T and the closely related strains was 19.5-23.3%. The major cellular fatty acids were summed feature 3 (C16:1ω7c and/or C16:1ω6c), summed feature 8 (C18:1ω6c and/or C18:1ω7c), C14:0, C16:0, and C17:0 cyclo. Several genes related to IAA production, phosphonate transport, phosphate solubilization and siderophore biogenesis were found in the MQR6T genome. Furthermore, inoculation with the strain MQR6T significantly improved plant height, trunk diameter, dry weight and P accumulation in roots and shoot of A. truncatum seedlings compared to non-inoculated control. These plant parameters were improved even further in the treatment with both inoculation and P fertilization. Our results suggested that MQR6T represented a new species we named Pantoea rhizosphaerae, as a plant growth-promoting rhizobacterium that can solubilize inorganic P and improve growth of A. truncatum seedlings, emerging as a potential strategy to improve A. truncatum cultivation.

Even though Jerusalem artichoke (Helianthus tuberosus L.) has strong resistance to abiotic stresses, salinity can still reduce the biomass of Jerusalem artichoke. The purpose of this study was to elucidate the differences in the development of Jerusalem artichoke and the dynamics of sugar throughout the growth period under high (7.23–8.15 g/kg) and low (3.20–4.32 g/kg) salinity stress in the field in Jiangsu Province, China. This study confirmed that high salinity promoted the conversion of reducing sugars to non-reducing sugars (fructans) in Jerusalem artichoke tubers, but significantly reduced the biomass of Jerusalem artichoke and advanced the peak time of the dry matter accumulation of aerial parts. In addition, in the early and late stages of tuberization, the total sugar content of tubers under low salinity conditions (786 ± 8 mg/g and 491 ± 8 mg/g) was 93.3% and 1.15 times than those under high salinity conditions, respectively. Moreover, the total sugar content in stems was consistently greater under high than low salinity conditions in the same period. The accumulation rate and the amount of dry matter were significantly higher in stems than in other tissues. Therefore, the aerial parts of “Nanyu No. 1” could be harvested before mid-to-early October, and the tubers after mid-November. This study revealed the internal reasons for the decreased yield of Jerusalem artichoke under salt stress, and provided theoretical basis and guidance for the cultivation and utilization of Jerusalem artichoke in saline-alkali soil.

Aerobic composting is one of the most economical ways to produce organic fertilizer from agricultural wastes. In this research, we independently developed a simple composting simulation reactor. The effects of biochar pyrolysised at different pyrolysis temperatures (B1-450 °C; B2-550 °C; and B3-650 °C) on nitrogen conversion (Total nitrogen (TN), ammonium nitrogen (NH4+-N), nitrate nitrogen (NO3−-N), cumulative amount of ammonia (CEA) and nitrous oxide (CEN) emission, nitrogen loss rate (NLR), etc.) and functional microbial community (cbbL, cbbM and nifH) structure in the composting system were studied. Results showed that the addition of biochar significantly improved the efficiency of composting, increased the NO3−-N concentration and reduced the NLR (%) in the composting system (B3 (31.4 ± 2.73)

Abstract Biochar addition can enhance soil quality and sequester carbon. However, changes in soil organic matter (SOM) molecular compositions in response to long‐term biochar addition have rarely been studied. Therefore, we quantified soil organic carbon fractions, carbon‐cycling enzyme activities, and a range of organic compounds and lignin‐derived phenols in the rhizosphere and bulk soils in different rice growth stages in the 8‐year field trial with biochar application rates of 0 (BC‐0), 4.5 (BC‐L), and 13.5 t ha−1 year−1 (BC‐H). We found that higher amounts of biochar addition (BC‐H) increased labile organic carbon (LOC), dissolved organic carbon (DOC) and particulate organic carbon (POC), and promoted activities of α‐1,4‐glucosidase, β‐D‐cellobiohydrolase and β‐1,4‐xylosidase; in contrast, BC‐L treatment reduced activities of these enzymes. The concentrations of dichloromethane/methanol‐extractable plant‐ and microbial‐derived organic compounds in the rhizosphere and bulk soils at tillering decreased significantly in the treatment with low amount of biochar addition. BC‐L also significantly altered the concentrations of extracted compounds in the rhizosphere soil at tillering and harvest. Concentration of lignin in the bulk soil was significantly reduced in BC‐L at tillering (by 19%) and harvest (by 28%). The concentrations of extracted compounds (e.g., n‐alkanols, n‐alkanoic acids, steroids, and carbohydrates) and lignin were generally significantly higher in the bulk than the rhizosphere soil at tillering and harvest. Long‐term biochar application (BC‐H) promoted lignin decomposition in the bulk soil (at tillering) and the rhizosphere soil (at harvest). Hence, biochar decreased stability of lignin in paddy soil. Our study provided evidence that long‐term biochar application changed the molecular composition and dynamics of degradation of SOM. These results deepen our understanding of the mechanisms governing SOM stability in agricultural ecosystems.

Plants adjust root morphological and/or exudation traits in response to phosphorus (P) mobilization mediated by microorganisms. We hypothesized that straw application coupled with P fertilization would influence microbial P and then root nutrient-acquisition strategies related to crop growth. Root morphological (length and average diameter) and exudation traits (acid phosphatase and carboxylates) of Brassica chinensis, Solanum lycopersicum, Lactuca sativa, and Vigna unguiculata in response to microbial P dynamics were characterized in no-P and P-fertilized soil with/without straw addition. Straw addition increased the growth of fungi and bacteria, stimulating microbial P immobilization at day 24. The high microbial abundance was associated with four tested crops having short roots in straw-amended compared with no-straw soil at day 24. In straw-amended soil, B. chinensis and S. lycopersicum shifted toward root P-acquisition strategies based on fast elongation and strong carboxylate exudation from days 24 to 40. Such effective root P-acquisition strategies together with microbial P release increased shoot P content in S. lycopersicum in straw-amended compared with those without straw at day 40. Conversely, L. sativa and V. unguiculata produced short roots in response to the stable (or even increased) microbial P after straw addition till day 40. In straw-amended soil, high P application stimulated root elongation and carboxylate exudation in L. sativa and V. unguiculata, whereas carboxylate exudation by S. lycopersicum was decreased compared with the straw-amended but non-fertilized treatment at day 40. In summary, root P-acquisition strategies in response to microbial P differed among the tested crop species. Phosphorus fertilization needs to be highlighted when returning straw to enhance P-use efficiency in vegetable cropping systems.

Mining operations degrade natural ecosystems by generating a large quantity of mine tailings. Mine tailings remain in dams/open ponds without further treatment after valuable metals such as iron ore have been extracted. Therefore, rehabilitation of tailings to mitigate the negative environmental impacts is of the utmost necessity. This review compares existing physical, chemical and amendment-assisted phytoremediation methods in the rehabilitation of mine tailings from the perspective of cost, reliability and durability. After review and discussion, it is concluded that amendment-assisted phytoremediation has received comparatively great attention; however, the selection of an appropriate phytoremediator is the critical step in the process. Moreover, the efficiency of phytoremediation is solely dependent on the amendment type and rate. Further, the application of advanced plant improvement technologies, such as genetically engineered plants produced for this purpose, would be an alternative solution. Further research is needed to determine the suitability of this method for the particular environment.

Soil ammonium toxicity can decrease plant growth, and many crop species have low resistance to ammonium, including canola, an economically important crop. Different genotypes may differ in their resistance to ammonium toxicity, and therefore determining if there are genotypes that exhibit variation in their ability to tolerate soil ammonium is a research priority. Here, we evaluate how soil ammonium impacts canola root and shoot growth and characterise differences among canola genotypes in regard to resistance to ammonium toxicity. In the first experiment, eight ammonium chloride treatments and five calcium nitrate treatments were tested for their impact on the canola genotype Crusher TT, where high application (60 mg N/kg soil) significantly decreased the dry weight of canola shoots and roots and acidified the soil from pHCaCl2 5.9 to 5.6. In the second experiment, 30 canola genotypes were screened at selected concentrations of NH4+-N, using nitrate as the control. There was wide variation among genotypes in sensitivity to high NH4+-N application. Genotypes G16, G26, and G29 had greater shoot dry weights and the highest shoot N concentration of all genotypes, and G16, G26, and G28 had root dry weight up to 35% higher at high soil NH4+-N compared with other genotypes. In contrast, genotypes G3, G13, and G30 showed the largest reduction in shoot weight, and genotypes G13, G23, and G30 showed the largest reduction in root weight at high NH4+-N application. Residual NH4+-N/kg soil in soil was higher for sensitive than resistant genotypes, suggesting lower NH4+-N use in the former. These results reveal the potential for selecting canola genotypes that are resistant to high NH4+-N concentrations in soil.

Existing technologies for lime (CaCO3) incorporation into acidic field soils result in the heterogeneous distribution of limed and acidic soil sections. In a study characterising the response of wheat (Triticum aestivum L.) to the amendment of an acidic soil profile with vertically limed slots [1], elucidation of the dynamics of root proliferation within the acidic and limed soil sections was a prerequisite to understanding the mechanisms driving the above-ground responses. Rubidium (Rb) has been used widely as a non-radioactive tracer for root activity [2] in soil. However, the contrasting pH in a heterogeneously limed soil profile and related aluminium toxicity effects to roots can influence the availability and uptake of Rb, and quantitative data relating Rb uptake to root phenology in this scenario are lacking. To validate the use of Rb as a tracer for root activity within vertically limed slots in an acidic soil profile, its uptake by wheat roots from acidic or limed sections of subsoil, and its relation to root architecture was assessed.Wheat plants were grown in a glasshouse in 29 cm deep, vertically split soil columns with acidic (pH 3.9), Al-toxic subsoil on one side and the same soil amended with lime on the other side. Rubidium chloride was applied at 5, 10 or 20 mg Rb kg−1 to either limed or acidic soil sections. Wheat plants were grown for 28 days, after which the Rb content in shoots and the root length and diameter in each of the discrete soil sections was measured.Foremost, the Rb amendments (5, 10 or 20 mg Rb kg−1 soil) did not induce any toxic effects; shoot dry weight and root length in the limed and acidic sections of the subsoil were not statistically different among the rubidium-amended and non-amended treatments, regardless of its placement (limed vs. acidic sections). Average root lengths in the limed sections of the subsoil (69.5 m section−1) were approximately 10-fold greater than in the acidic sections (6.3 m section−1). Likewise, the concentration of Rb in shoots was, on average, 7-fold greater where Rb was applied to the limed (vs. acidic) subsoil section and was positively influenced by the rate of Rb amendment in the limed (p ≤ 0.05), but not the acidic section of the subsoil. Rubidium uptake into shoots was significantly correlated (p ≤ 0.05) with the length of roots within the Rb-amended subsoil section. The uptake of Rb from acidic or limed subsoil sections was determined by the root length in the Rb-amended subsoil section, regardless of the rate of Rb amendment. The uptake of Rb per unit of root length from acidic or limed sections of subsoil was not significantly different.The data validate the use of Rb as a tracer for the dynamics of root length proliferation in limed subsoil sections in a heterogeneously limed acidic soil profile.

Summary: Feeding the world’s growing population requires continuously increasing crop yields with less fertilizers and agrochemicals on limited land. Focusing on plant belowground traits, especially root-soil-microbe interactions, holds a great promise for overcoming this challenge. The belowground root-soil-microbe interactions are complex and involve a range of physical, chemical, and biological processes that influence nutrient-use efficiency, plant growth and health. Understanding, predicting, and manipulating these rhizosphere processes will enable us to harness the relevant interactions to improve plant productivity and nutrient-use efficiency. Here, we review the recent progress and challenges in root-soil-microbe interactions. We also highlight how root-soil-microbe interactions could be manipulated to ensure food security and resource sustainability in a changing global climate, with an emphasis on reducing our dependence on fertilizers and agrochemicals.

Returning straw into soil could increase soil organic carbon (SOC) and promote crop growth. However, little has been reported on the source of C for increased SOC (straw C or crop photosynthetic C). To investigate the assimilation of photosynthetic C and its distribution in soil in the maize growth season, we set up a 1-year 13C pulse-labeling experiment in a consecutive maize-straw-returning long-term trial. Four treatments were included: no straw return (control), straw mulching on the soil surface (cover), return in 0–20 cm layer (shallow), and 20–40 cm layer (deep). We found that the deep straw incorporation significantly (P < 0.05) increased maize 100-grain weight (by 7.8%), yield in the coming year (by 10.5%), and SOC (by 13.4%) compared with the control. During the growing season, the deep straw incorporation increased photosynthetic 13C assimilation in shoots by 17.4% and the partitioning of photosynthetic 13C to soil by 7.9% at early jointing, and by 11.5% at maturity. The contribution of photosynthetic C to microbial biomass C (MBC) and dissolved organic C (DOC) was highest at jointing, and at harvest amounted to 39.1 % of MBC and 28.8% of DOC. The results highlighted the importance of regulating the soil carbon dynamics via the deep straw return strategy. In conclusion, deep straw incorporation significantly increased photosynthetic efficiency and facilitated partitioning of photosynthetic C to roots and soil, thus promoting maize growth and yield.

The genotype CR60 is a spontaneous Cherry Red variant (containing granular red dapples on flue-cured leaves) of the Yunyan 87 (Y87) tobacco; it accumulates higher concentration of iron (Fe) in leaves than Y87, but the physiological differences between them remain largely unknown. We investigated the physiological and molecular mechanisms of CR60 in response to Fe deficiency under hydroponic conditions. Our results showed no significant phenotypic difference between Y87 and CR60 at optimal (40 μM) and high Fe (160 and 320 μM) concentrations. By contrast, CR60 exhibited higher tolerance to Fe deficiency (0 μM) than Y87, as shown by higher concentrations of chlorophyll in CR60 leaves after 21-day Fe-deficiency stress. Transcriptome profiling coupled with RT-PCR analyses found that the expression of IRT1 and several genes associated with chlorophyll biosynthesis and photosynthesis (e.g., PRO, GSA, FD1, PsbO, and PC) was higher in CR60 than Y87. These results indicated that CR60 maintains sufficient Fe uptake, chlorophyll biosynthesis and photosynthetic rate when subjected to Fe starvation.

Nutrient type and plant functional group are both important in influencing proliferation of roots or hyphae and their benefit to plant growth in nutritionally heterogeneous environments. However, the studies quantifying relative importance of roots vs. hyphae affecting the plant response to nutrient heterogeneity are lacking. Here, we used meta-analysis based on 879 observations from 66 published studies to evaluate response patterns of seven variables related to growth and morphological traits of plants and mycorrhizal fungi in nutritionally heterogeneous environments. We found that phosphorus [P] and organic fertilizer [OF] supply significantly increased shoot (+18.1 and +25.9%, respectively) and root biomass (+31.1 and +23.0%, respectively) and root foraging precision (+11.8 and +20.4%, respectively). However, there was no significant difference among functional groups of herbs (grasses, forbs, and legumes), between herbs and woody species, and between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) tree species in the shoot, root and mycorrhizal fungi responses to nutrient heterogeneity, except for root biomass and root foraging precision among grasses, forbs, and legumes, and mycorrhizal hyphal foraging precision between AM and ECM tree species. Root diameter was uncorrelated with neither root foraging precision nor mycorrhizal hyphal foraging precision, regardless of mycorrhizal type or nutrient type. These results suggest that plant growth and foraging strategies are mainly influenced by nutrient type, among other factors including plant functional type and mycorrhizal type.

Polymer-coated rock mineral fertiliser (RMF) has the potential to increase wheat growth and yield; however, its effect on grain protein concentration (GPC) and nitrogen-use efficiency (NUE) remains unclear. Therefore, we examined the efficacy of slow-release RMF combined with microbial consortium inoculant (MI) compared with inorganic fertiliser (IF) with or without the MI to explore their effects on wheat growth, NUE, GPC, grain protein yield and grain yield. The glasshouse experiment was conducted with three factors (fertiliser type (control, RMF and IF), fertiliser rate (0, 23 and 46 mg N kg−1 soil), and MI (with or without)) replicated four times and harvested twice (anthesis and maturity). The treatments were arranged in a randomised complete block design. NUE was higher in plants treated with RMF plus MI compared to IF (with or without MI), likely due to extensive root system, higher shoot N content (at anthesis and maturity) and grain N content in plants treated with RMF plus MI than IF. The application of RMF enhanced grain yield and GPC compared with IF. The grain yield increased due to more grains in RMF-treated than IF-treated plants. The RMF application increased N content in shoots at anthesis and maturity and grain N content, which increased GPC compared to IF-treated plants. RMF in combination with MI can be viewed as a practical approach to assist RMF in supplying nutrients to improve NUE, grain yield and GPC in wheat.

Blueberry has high nutritional value and is favored by consumers, so the planting area is increasing. However, due to the influence of climate conditions and the edaphic environment, achieving high production and the healthy growth of blueberries has become a major problem. In this study, we collected soil and blueberry plants which had normal and limited growth to determine the underlying causes of poor growth by characterizing soil pH, EC, enzyme activities and the microbiome, plant growth properties, and root metabolites. The results showed that the pH of the blueberry rhizosphere soil was less than 6.0 in the case of plants growing well, and higher than 6.0 in case of plants growing poorly. The activities of acid phosphatase and invertase were significantly higher in the rhizosphere soil of the normally growing than growth-limited blueberry plants. The relative abundance of Proteobacteria and Saccharibacteria was higher in the rhizosphere soil of normally growing than growth-limited blueberry plants and they were positively correlated with activity of soil acid phosphatase. Ascomycota, as the dominant fungi, had the highest relative abundance in the rhizosphere soil of growth-limited blueberry plants. The six metabolites showing enrichment in the KEGG pathway analysis were thymidine, cholic acid, raffinose, p-salicylic acid, astaxanthin, and inosine. It was found that flavonoids were correlated positively with soil fungi abundance. The contents of flavonoids apin, rutin and epigallocatechin were significantly higher in roots of growth-limited than normally growing blueberry plants. The content of the flavonoid daidzin was significantly higher in the roots of poorly growing blueberries compared to normally growing ones. In conclusion, the growth of blueberry was significantly related to soil organic matter, soil enzyme activity and soil microbial community diversity.

Abstract Rhizosphere interactions between intercropping maize and alfalfa to increase phosphorus (P) acquisition remain largely unknown. This study aimed to investigate the mechanisms underlying niche complementarity to increase P acquisition in the maize/alfalfa mixture by influencing root/rhizosphere interactions. Maize was grown alone (single maize) or with maize (maize/maize) or alfalfa (maize/alfalfa) with low P (30 mg P kg−1 soil) and high P (150 mg P kg−1 soil) supplies. The target maize had greater shoot biomass and P content when grown with alfalfa than maize. Compared with maize, alfalfa had higher secretion of carboxylates and acid phosphatase, suggesting a stronger capacity to mobilize soil P. Phosphorus deficiency also increased the specific root length and the proportion of thin roots (diameter

Soil bacterial diversity and community composition are crucial for soil health and plant growth, and their dynamics in response to agronomic practices are poorly understood. The aim of this study was to investigate the response of soil bacterial community structure to the changes of sowing methods, soil depth and distance to roots in a winter wheat-summer maize crop rotation system on the Loess Plateau in china (35°17′38′′N, 111°40′24′′E). The experiment was laid out as completely randomized block design with three replications. Sowing methods trialed were: traditional sowing (TS), film-mulched ridge and furrow sowing (FMR&F), wide ridge and narrow furrow sowing (WR&NF) and unplanted control (CK). The result showed that the WR&NF sowing method treatment significantly decreased soil bacterial diversity (Chao 1 and Shannon indices) compared to the TS and FMR&F treatment, but increased abundance of beneficial bacteria such as genera Bacillus and Pseudomonas compared to the TS treatment. These genera showed a stronger correlation with soil properties and contributed to the soil nutrient cycling and crop productivity. Bacillus, Pseudomonas, Nevskia, and Lactococcus were the keystone genera in this winter wheat-summer maize rotation system on the Loess Plateau. Strong correlations between changes in soil properties and soil bacterial diversity and abundance were identified. In summary, we suggest that the WR&NF treatment, as a no-mulching film and no-deep tillage sowing method, would be the most suitable sowing technique in the winter wheat-summer maize rotation on Loess soil.

Background: Jerusalem artichoke (Helianthus tuberosus L.) is moderately tolerant to salinity stress and has high economic value. The salt tolerance mechanisms of Jerusalem artichoke are still unclear. Especially in the early stage of Jerusalem artichoke exposure to salt stress, gene transcription is likely to undergo large changes. Previous studies have hinted at the importance of temporal expression analysis in plant transcriptome research. Elucidating these changes may be of great significance to understanding the salt tolerance mechanisms of it. Results: We obtained high-quality transcriptome from leaves and roots of Jerusalem artichoke exposed to salinity (300 mM NaCl) for 0 h (hour), 6 h, 12 h, 24 h, and 48 h, with 150 and 129 unigenes and 9023 DEGs (differentially expressed genes). The RNA-seq data were clustered into time-dependent groups (nine clusters each in leaves and roots); gene functions were distributed evenly among them. KEGG enrichment analysis showed the genes related to plant hormone signal transduction were enriched in almost all treatment comparisons. Under salt stress, genes belonging to PYL (abscisic acid receptor PYR/PYL family), PP2C (Type 2C protein phosphatases), GH3 (Gretchen Hagen3), ETR (ethylene receptor), EIN2/3 (ethylene-insensitive protein 2/3), JAZ (genes such as jasmonate ZIM-domain gene), and MYC2 (Transcription factor MYC2) had extremely similar expression patterns. The results of qRT-PCR of 12 randomly selected and function known genes confirmed the accuracy of RNA-seq. Conclusions: Under the influence of high salinity (300 mM) environment, Jerusalem artichoke suffer serious damage in a short period of time. Based on the expression of genes on the time scale, we found that the distribution of gene functions in time is relatively even. Upregulation of the phytohormone signal transduction had a crucial role in the response of Jerusalem artichoke seedlings to salt stress, and the genes of abscisic acid, auxin, ethylene, and jasmonic acid had the most obvious change pattern. Research emphasized the regulatory role of hormones under high salt shocks and provided an explorable direction for the study of plant salt tolerance mechanisms.

Hyperlipidemia is currently rising at an alarming rate in human populations around the world, and new innovative ways of alleviating hyperlipidemia are needed. The effects of Jerusalem artichoke inulin on hyperlipidemia and the intestinal microflora in mice fed high-fat diet (HFD) were investigated. Inulin-treated HFD-fed hyperlipidemic mice had decreased serum lipid hepatic triglyceride (TG), hepatic total cholesterol (TC) concentrations and atherogenic index (AI). The inulin treatment increased hepatic superoxide dismutase (SOD) activity and decreased hepatic malondialdehyde (MDA) concentration. Histological analysis of liver revealed a decrease in abundance of lipid droplets in inulin-treated HFD-fed hyperlipidemic mice. Illumina high-throughput sequencing technology was used to analyze the bacterial community structure of the intestinal contents of mice. Analysis showed that the inulin treatment improved intestinal microflora; in particular, it significantly increased the number of Bifidobacterium in the intestine of HFD-fed mice. Inulin is therefore potentially potent functional food for preventing and treating hyperlipidemia.

Seed germination and seedling growth are two essential early determinants of subsequent crop yield and quality. A high germination percentage of industrial hemp (Cannabis sativa L.) seed is required to import into Australia. The viability of hemp seed can decline rapidly depending on storage and other factors; hence, the quality of imported seed is not always reliable. Here, we aimed to investigate germination and early seedling growth responses of 14 industrial hemp varieties after being imported from various countries. Germination trials were conducted with 100 seeds of 14 varieties using a soil-less Petri dish assay and a compost growth medium under glasshouse conditions. We also assessed the effect of seed pre-treatments such as gibberellic acid (500 and 1000 mg·L−1), chlorine dioxide (500 and 1000 mg·L−1) and cold temperature (4 °C for 72 h) using 300 seeds of each of the three selected varieties in compost growth medium. Hemp varieties imported from China had higher germination and better seedling growth indices than those imported from Europe. All seed pre-treatments were associated with a decreasing trend in germination, but a positive effect on early growth responses was observed. Our findings indicate that the hemp variety Han FNQ performed better than many other varieties did regarding seed germination and seedling growth. Hemp seeds sanitising with 500 mg·L−1 of chlorine dioxide might improve the germination and early growth of seedlings.

Barley (Hordeum vulgare L.) is an important cereal crop, but its sustainable production is significantly hampered due to the presence of various edaphic stresses. Understanding the variability in root morphological traits among diverse barley genotypes is critical for selecting those with suitable root traits for breeding new cultivars better adapted to stress environments. Root morphological traits in an early growth stage (30 days after transplanting) in a panel of 189 barley genotypes (mostly advanced breeding lines) were assessed using a semi-hydroponic phenotyping platform followed by a validation experiment of eight genotypes with contrasting root systems in two soils. The phenotyping experiment showed large variation (coefficient of variation values ≥ 0.25) in 16 of 26 measured root and shoot traits. A strong correlation among most of the selected traits was identified. Principal component analysis indicated four principal components (eigenvalues >1) captured 79.5% of the total variation. Root traits, including total root length, root length at various depths, root diameter and root length ratio (top 20 cm vs. lower section), could be considered in the barley breeding programs. Consistent ranking of the selected eight genotypes based on root biomass and root length in both the semi-hydroponic system and the columns with two different soils confirmed root trait performance in different growth environments as well as the reliability of the phenotyping method. This study identified phenotypic variability in root morphological traits in barley genotypes in the early growth stage. The genotypic variability in root traits represents a basis for mapping quantitative trait loci (QTLs) and molecular markers, particularly focused on breeding lines with optimal root properties for the efficient acquisition of soil resources and adaptation to drought and other abiotic stresses.

To test an assumption that organic soil can ameliorate nutritional disorders associated with metal and salinity stresses, we exposed salt-sensitive strawberry and lettuce to four salinity (0–60 mM NaCl) and three contamination (0.3–5 mg Cd/kg) rates in peat (pHH2O = 5.5). The results showed that, even at 20 mM NaCl, salinity stress exerted a dominant effect on rhizosphere biogeochemistry and physiological processes, inducing leaf-edge burns, chlorosis/necrosis, reducing vegetative growth in crops; at ≥40 mM, NaCl mortality was induced in strawberry. Signifiacntly decreased K/Na, Ca/Na and Mg/Na concentration ratios with raising salinity were confirmed in all tissues. The combined CdxNaCl stresses (vs. control) increased leaf Cd accumulation (up to 42-fold in lettuce and 23-fold in strawberry), whereas NaCl salinity increased the accumulation of Zn (>1.5-fold) and Cu (up to 1.2-fold) in leaves. Lettuce accumulated the toxic Cd concentration (up to 12.6 mg/kg) in leaves, suggesting the strong root-to-shoot transport of Cd. In strawberry Cd, concentration was similar (and sub-toxic) in fruits and leaves, 2.28 and 1.86 mg/kg, respectively, suggesting lower Cd root-to-shoot translocation, and similar Cd mobility in the xylem and phloem. Additionally, the accumulation of Cd in strawberry fruits was exacerbated at high NaCl exposure (60 mM) compared with lower NaCl concentrations. Thus, in salinized, slightly acidic and organically rich rhizosphere, pronounced organo- and/or chloro-complexation likely shifted metal biogeochemistry toward increased mobility and phytoavailability (with metal adsorption restricted due to Na+ oversaturation of the caton exchange complex in the substrate), confirming the importance of quality water and soils in avoiding abiotic stresses and producing non-contaminated food.

Co-cropping is an eco-friendly strategy to improve the phytoremediation capacity of plants growing in soils contaminated with heavy metals such as cadmium (Cd). This study was conducted to investigate the effects of co-cropping Indian mustard (Brassicajuncea) and silage maize (Zeamays) and applying peat on the phytoremediation of a Cd-contaminated acid paddy soil via characterizing plant growth and Cd uptake in pot experiments. There were six planting patterns (Control: no plants; MI-2 and MI-4: mono-cropping of Indian mustard at low and high densities, respectively; MS: mono-cropping of silage maize; CIS-2 and CIS-4: co-cropping of Indian mustard at low and high densities with silage maize, respectively) and two application rates of peat (NP: 0; WP: 30 g kg−1). When Indian mustard and silage maize were co-cropped, the shoot biomass of Indian mustard plants per pot was significantly (p < 0.05) lower than that obtained in the mono-cropping systems, with a substantial reduction (55–72%) in the same plant density group. The shoot biomass of silage maize plants in the mono-cropping systems did not differ significantly from that in the co-cropping systems regardless of the density of Indian mustard. The growth-promoting effect of the peat application was more pronounced in Indian mustard than silage maize. Under the low density of Indian mustard, the co-cropping systems significantly (p < 0.05) decreased Cd uptake by silage maize. Additionally, soil amendment with peat significantly (p < 0.05) increased shoot Cd removal rate and Cd translocation factor value in the co-cropping systems. Taken together, the results demonstrated that silage maize should be co-cropped with Indian mustard at an appropriate density in Cd-polluted soils to achieve simultaneous remediation of Cd-contaminated soils (via Indian mustard) and production of crops (here, silage maize). Peat application was shown to promote the removal of Cd from soil and translocation of Cd into shoots and could contribute to enhanced phytoremediation of Cd-contaminated acid paddy soil.

Phosphorus (P) fertiliser is applied regularly to the nutrient-poor sandy soils in southwestern Australia to elevate and/or maintain pasture production. This study aimed to characterise differential growth, root carboxylate exudation, and mycorrhizal responses in three temperate perennial pasture grasses at variable P supply. Tall fescue (Festuca arundinacea L. cv. Prosper), veldt grass (Ehrharta calycina Sm. cv. Mission), and tall wheatgrass (Thinopyrum ponticum L. cv. Dundas) with five P rates varying from 0 to 100 mg P kg−1 soil were evaluated in a controlled environment. Rhizosphere carboxylate exudation and mycorrhizal colonisation were assessed. Veldt grass produced the maximum shoot dry weight, highest agronomic phosphorus-use efficiency at low P supply, as well as the highest specific root length and shoot P content at all P rates. Across species, the maximum shoot weight was obtained at 20 and 50 mg P kg−1 soil, which differed significantly from the two lowest P rates (0 and 5 mg P kg−1 soil). Phosphorus application influenced carboxylate exudation, with plants exuding acetate only in the zero P treatment, and citrate and malonate in the P-supplemented treatments. In all three species, acetate and malonate were the major carboxylates exuded (37–51% of the total). Only tall wheatgrass released trans-aconitate. Citrate and malonate concentrations in the rhizosphere increased with P supply, suggesting their important role in P acquisition. Phosphorus applications reduced arbuscular mycorrhizal colonisation and increased root diameter as the P rate increased. Root carboxylate exudation in low-P soil played a role in mobilisation of P via P solubilisation, but the role of exuded carboxylate in soils well supplied with P might be diminished.

Optimisation of potassium (K) use efficiency in pastures on sandy soil is challenging. We characterised growth response, root carboxylate exudation and mycorrhizal colonisation in three perennial pasture grasses: tall fescue (Festuca arundinacea L.), veldt grass (Ehrharta calycina Sm.) and tall wheatgrass (Thinopyrum ponticum L.) in two glasshouse experiments with: (1) four K rates (0, 40, 80 and 120 mg K kg-1 soil), and (2) four N and K treatments (no N and K (–N–K), 81 mg N kg-1 soil but no K, 80 mg K kg-1 soil but no N, and N at 81 and K at 80 mg kg-1 soil (+N+K)) in low-K sandy soil. Veldt grass had the highest shoot dry weight and shoot P content, but the lowest mycorrhizal colonisation. Potassium fertilisation had no significant impact on exudation of citrate and oxalate. The K0 plants had significantly lower exudation of acetate and total carboxylates than K40 plants. The +N+K plants had maximum shoot growth at both harvests (30 and 60 days after sowing (DAS)) and highest N and K shoot contents at 60 DAS. The –N–K plants exuded maximum amounts of citrate and malate at 30 DAS, but at 60 DAS tall fescue had the highest rhizosphere concentrations of citrate and malate in the +N+K treatment. At 60 DAS, mycorrhizal colonisation was significantly lower with than without N and K fertilisation. We concluded that pasture grasses could yield well even in inherently low-K soil without external K fertilisation and mycorrhizal symbiosis. However, the +N+K plants had the highest yield and root carboxylate exudation.

Aluminum (Al) toxicity is a key factor limiting plant growth and crop production on acid soils. Increasing the plant Al-detoxification capacity and/or breeding Al-resistant cultivars are a cost-effective strategy to support crop growth on acidic soils. The plasma membrane H+-ATPase plays a central role in all plant physiological processes. Changes in the activity of the plasma membrane H+-ATPase through regulating the expression and phosphorylation of this enzyme are also involved in many plant responses to Al toxicity. The plasma membrane H+-ATPase mediated H+ influx may be associated with the maintenance of cytosolic pH and the plasma membrane gradients as well as Al-induced citrate efflux mediated by a H+-ATPase-coupled MATE co-transport system. In particular, modulating the activity of plasma membrane H+-ATPase through application of its activators (e.g., magnesium or IAA) or using transgenics has effectively enhanced plant resistance to Al stress in several species. In this review, we critically assess the available knowledge on the role of the plasma membrane H+-ATPase in plant responses to Al stress, incorporating physiological and molecular aspects.

Zinc (Zn) is an important micronutrient that can alleviate cadmium (Cd) toxicity to plants and limit Cd entry into the food chain. However, little is known about the Zn-Cd interactions in pasture plants. We characterized the effects of foliar Zn application and Cd uptake by ryegrass (Lolium rigidum L.) and clover (Trifolium subterraneum L.) grown on Cd-contaminated soils; all combinations of foliar Zn applications (0, 0.25 and 0.5% (w/v) ZnSO4·7H2O) and soil Cd concentrations (0, 2.5 and 5 mg Cd kg-1) were tested. For both plant species, soil concentrations of DTPA-extractable Cd and Zn increased with an increase in the Cd and Zn treatments, respectively. Compared with L. rigidum, T. subterraneum accumulated, respectively, 3.3- and 4.1-fold more Cd in the 2.5-Cd and 5-Cd treatments and about 1.3-, 2.3- and 2.8-fold more Zn in the No-Zn, 0.25-Zn and 0.5-Zn treatments. Also, DTPA-Zn concentration was higher in soil after T. subterraneum than L. rigidum growth regardless of Zn applications. Foliar application of 0.25% (w/v) Zn significantly decreased the total Cd concentration in shoots of both species grown in the Cd-contaminated soil and ameliorated the adverse effects of Cd exposure on root growth, particularly in T. subterraneum.

Nitrogen (N) is a major nutrient needed to attain optimal grain yield (GY) in all environments. Nitrogen fertilisers represent a significant production cost, in both monetary and environmental terms. Developing genotypes capable of taking up N early during development while limiting biomass production after establishment and showing high N-use efficiency (NUE) would be economically beneficial. Genetic variation in NUE has been shown previously. Here we describe the genetic characterisation of NUE and identify genetic loci underlying N response under different N fertiliser regimes in a bread wheat population of doubled-haploid lines derived from a cross between two Australian genotypes (RAC875 × Kukri) bred for a similar production environment. NUE field trials were carried out at four sites in South Australia and two in Western Australia across three seasons. There was genotype-by-environment-by-treatment interaction across the sites and also good transgressive segregation for yield under different N supply in the population. We detected some significant Quantitative Trait Loci (QTL) associated with NUE and N response at different rates of N application across the sites and years. It was also possible to identify lines showing positive N response based on the rankings of their Best Linear Unbiased Predictions (BLUPs) within a trial. Dissecting the complexity of the N effect on yield through QTL analysis is a key step towards elucidating the molecular and physiological basis of NUE in wheat.

Genetic variation has been observed in both protein concentration in wheat grain and total protein content (protein yield). Here we describe the genetic analysis of variation for grain protein in response to nitrogen (N) supply and locate significant genomic regions controlling grain protein components in a spring wheat population. In total, six N use efficiency (NUE) field trials were carried out for the target traits in a sub-population of doubled haploid lines derived from a cross between two Australian varieties, RAC875 and Kukri, in Southern and Western Australia from 2011 to 2013. Twenty-four putative Quantitative Trait Loci (QTL) for protein-related traits were identified at high and low N supply and ten QTL were identified for the response to N for the traits studied. These loci accounted for a significant proportion of the overall effect of N supply. Several of the regions were co-localised with grain yield QTL and are promising targets for further investigation and selection in breeding programs.

In order to investigate the mechanisms in two Jerusalem artichoke (Helianthus tuberosus L.) genotypes that hyperaccumulate Cd, a sand-culture experiment was carried out to characterize fractionation of Cd in tissue of Cd-hyperaccumulating genotypes NY2 and NY5. The sequential extractants were: 80% v/v ethanol (FE), deionized water (FW), 1 M NaCl (FNaCl), 2% v/v acetic acid (FAcet), and 0.6 M HCl (FHCl). After 20 days of treatments, NY5 had greater plant biomass and greater Cd accumulation in tissues than NY2. In both genotypes the FNaCl fraction was the highest in roots and stems, whereas the FAcet and FHCl fractions were the highest in leaves. With an increase in Cd concentration in the culture solution, the content of every Cd fraction also increased. The FW and FNaCl ratios in roots were lower in NY5 than in NY2, while the amount of other Cd forms was higher. It implied that, in high accumulator, namely, NY5, the complex of insoluble phosphate tends to be shaped more easily which was much better for Cd accumulation. Besides, translocation from plasma to vacuole after combination with protein may be one of the main mechanisms in Cd-accumulator Jerusalem artichoke genotypes.