Project description:Phosphorus is one of the most important macronutrients that is required for plant growth and development. However, stress under low-P conditions has become a limiting factor that affects crop yields and qualities. Plants have developed strategies to cope with this, while few genes associated with low-P tolerance have been identified in soybean. We used microarrays to detail the global programme of gene expression under different phosphorus treatments of two soybean accessions CD and YH with different phosphorus efficiency. The roots and leaves of a low-P-tolerant accession and a low-P-sensitive accession were harvested after 10 days of hydroponics under different P treatments, each with three biological replicates.Then microarray chips were performed on the 24 samples. We sought to identify genes associated with low-P stress. To that end, we analyzed the differently expressed genes between different P treatments, different accessions and different tissues.
Project description:Phosphorus is one of the most important macronutrients that is required for plant growth and development. However, stress under low-P conditions has become a limiting factor that affects crop yields and qualities. Plants have developed strategies to cope with this, while few genes associated with low-P tolerance have been identified in soybean. We used microarrays to detail the global programme of gene expression under different phosphorus treatments of two soybean accessions CD and YH with different phosphorus efficiency.
Project description:Abiotic stress causes disturbances in the cellular homeostasis. Re-adjustment of balance in carbon, nitrogen and phosphorus metabolism therefore plays a central role in stress adaptation. However, it is currently unknown which parts of the primary cell metabolism follow common patterns under different stress conditions and which represent specific responses. To address these questions, changes in transcriptome, metabolome and ionome were analyzed in maize source leaves from plants suffering low temperature, low nitrogen (N) and low phosphorus (P) stress. The selection of maize as study object provided data directly from an important crop species and the so far underexplored C4 metabolism. Growth retardation was comparable under all tested stress conditions. The only primary metabolic pathway responding similar to all stresses was nitrate assimilation, which was down-regulated. The largest group of commonly regulated transcripts followed the expression pattern: down under low temperature and low N, but up under low P. Several members of this transcript cluster could be connected to P metabolism and correlated negatively to different phosphate concentration in the leaf tissue. Accumulation of starch under low temperature and low N stress, but decrease in starch levels under low under low P conditions indicated that only low P treated leaves suffered carbon starvation. In conclusion, maize employs very different strategies for management of nitrogen and phosphorus metabolism under stress. While nitrate assimilation was regulated depending on demand by growth processes, phosphate concentrations changed depending on availability, thus building up reserves under excess conditions. Carbon and energy metabolism of the C4 maize leaves were particularly sensitive to P starvation. Responses of maize source leaves to low temperature, low nitrogen and low phosphorus conditions were tested in independent single-stress experiments. Seedlings were cultivated in pots containing nutrient-poor peat soil under the controlled conditions of a growth chamber. The plants were fertilized with modified Hoagland solutions, containing 15mM KNO3 and 0.5mM KH2PO4 for control conditions; for low N and low P treatment, the nutrient concentrations were reduced to 0.15mM KNO3 and 0.1mM KH2PO4, respectively. Low temperature treated plants were always supplied with control nutrient solution. Plants from the nitrogen and phosphorus experiment as well as the control temperature plants were exposed to 28°C during the day and 20°C during the night. Low temperature treatment was limited to the night period and was reduced to 4°C for the 10h dark period. Source leaf lamina were harvested at day 20 (low temperature experiment) or day 30 after start of germination (low nitrogen and low phosphorus experiment) for parallel analysis of transcriptome, metabolome and ion profiles. The molecular data is further supplemented by phenotypic characterization of the maize seedlings under investigation.
Project description:The regulatory effects of uneven phosphorus supplies on phosphorus transport in soybean roots is still unclear. To further analyze the regulatory effects of low-phosphorus stress on phosphorus transport in soybean roots and the effects of uneven phosphorus application on the physiological mechanism of phosphorus transport in soybean roots, dual-root soybean plants were prepared via grafting, and a sand culture experiment was performed.
Project description:Abiotic stress causes disturbances in the cellular homeostasis. Re-adjustment of balance in carbon, nitrogen and phosphorus metabolism therefore plays a central role in stress adaptation. However, it is currently unknown which parts of the primary cell metabolism follow common patterns under different stress conditions and which represent specific responses. To address these questions, changes in transcriptome, metabolome and ionome were analyzed in maize source leaves from plants suffering low temperature, low nitrogen (N) and low phosphorus (P) stress. The selection of maize as study object provided data directly from an important crop species and the so far underexplored C4 metabolism. Growth retardation was comparable under all tested stress conditions. The only primary metabolic pathway responding similar to all stresses was nitrate assimilation, which was down-regulated. The largest group of commonly regulated transcripts followed the expression pattern: down under low temperature and low N, but up under low P. Several members of this transcript cluster could be connected to P metabolism and correlated negatively to different phosphate concentration in the leaf tissue. Accumulation of starch under low temperature and low N stress, but decrease in starch levels under low under low P conditions indicated that only low P treated leaves suffered carbon starvation. In conclusion, maize employs very different strategies for management of nitrogen and phosphorus metabolism under stress. While nitrate assimilation was regulated depending on demand by growth processes, phosphate concentrations changed depending on availability, thus building up reserves under excess conditions. Carbon and energy metabolism of the C4 maize leaves were particularly sensitive to P starvation.
Project description:In the study, two soybean genotypes were selected to conduct high and low P, high and low Mg, and AM fungal inoculation treatments, combined with RNA-seq sequencing technique in order to investigate the physiological and molecular mechanisms of the symbiosis between soybean and AM fungi affected by P and Mg treatments. The results showed that both Mg application and AM fungal inoculation were beneficial to promote soybean growth under low P condition. And there was a synergistic effect between the Mg concentration and the P concentration in the root of HN112 under the inoculation condition. RNA-seq sequencing was carried out using the roots of P-efficient soybean HN89 under different Mg and inoculation treatments with low P condition, and the difference of gene expression profiles was analyzed between high and low Mg treatments, and different inoculation treatments. According to the analysis of GO function classification and KEGG enrichment, under high Mg condition, the metabolic pathway was mainly enriched in lipid metabolism and glucose metabolism pathway under the inoculation treatment compared with the non-inoculation treatment, which regulated carbon metabolism pathway. Under the low Mg condition, the metabolic pathway was mainly enriched in the photosynthesis- antenna protein pathway to regulate the photosynthesis pathway under the inoculation treatment compared with the non-inoculation treatment. At the same time, the inoculation treatment significantly increased soybean root starch concentration under low Mg condition, compared with the non-inoculation treatment, suggesting that the significant up-regulation of a large number of photosynthesis related genes might be related to the significant increase of starch concentration at this treatment.
Project description:Increased root H+ secretion is known as a strategy of plant adaption to low phosphorus (P) stress by enhancing mobilization of sparingly soluble P-sources. However, it remains fragmentarywhether enhanced H+ exudation could reconstruct the plant rhizosphere microbial community under low P stress. The present study found that P deficiency led to enhanced H+ exudation from soybean (Glycine max) roots. Three out of all eleven soybean H+-pyrophosphatases (GmVP) geneswere up-regulated by Pi starvation in soybean roots. Among them, GmVP2 showed the highest expression level under low P conditions. Transient expression of a GmVP2-green fluorescent protein chimera in tobacco (Nicotiana tabacum) leaves, and functional characterization of GmVP2 in transgenic soybean hairy roots demonstrated that GmVP2 encoded a plasma membrane transporter that mediated H+ exudation. Meanwhile, GmVP2-overexpression in Arabidopsis thaliana resulted in enhanced root H+ exudation, promoted plant growth, and improved sparingly soluble Ca-P utilization. Overexpression of GmVP2 also changed the rhizospheric microbial community structures, as reflected by a preferential accumulation of acidobacteria in the rhizosphere soils. These results suggested that GmVP2 mediated Pi-starvation responsive H+ exudation,which is not only involved in plant growth and mobilization of sparingly soluble P-sources, but also affects microbial community structures in soils.
Project description:Proton toxicity is one of the major environmental stresses limiting crop production, and becomes increasingly serious because of anthropogenic activities. To understand acid tolerance mechanisms, the plant growth, mineral nutrient accumulation and global transcriptome changes in soybean (Glycine max) in response to long-term acid stress were investigated. Results showed that acid stress significantly inhibited soybean root growth, but exhibited slight effects on the shoot growth. Moreover, concentrations of essential mineral nutrients were significantly affected by acid stress, mainly dependent on soybean organs and mineral nutrient types. The concentrations of phosphorus (P) and molybdenum (Mo) in both leaves and roots, nitrogen (N) and potassium (K) in roots and magnesium (Mg) in leaves were significantly decreased, respectively. Whereas, the concentrations of calcium (Ca), sulfate (S) and iron (Fe) were increased in both leaves and roots. Transcriptome analyses in soybean roots resulted in identifying 419 up-regulated and 555 down-regulated genes under acid conditions. A total of 38 differentially expressed genes (DEGs) were involved in mineral nutrient transportation. Among them, all the detected five GmPTs and GmZIPs, two GmAMTs and GmKUP genes, together with GmIRT1, GmNramp5, GmVIT2.1, GmSKOR, GmTPK5 and GmHKT1, were significantly suppressed. Moreover, the genes encoding transcription factors (e.g., GmSTOP2s and a GmPHL1), and genes involved in pH stat metabolic pathways were significantly up-regulated by low pH stress in soybean roots. Taken together, it strongly suggested that maintaining pH stat and mineral nutrient homeostasis are adaptive strategies of soybean responses to acid stress, which might be regulated by a complex signaling network.
Project description:Low phosphate (LP) availability is a critical limiting factor affecting soybean production. Soybean plants develop a series of strategies to adapt phosphate limitation condition. To know the underlying molecular mechanisms responsible for LP stress response. A label-free quantification (LFQ) analysis of soybean leaves grown under low and high phosphate condition was performed.
Project description:In the early stages (30 days) of phosphorus deficiency stress, Epimedium pubescens leaves cope with short-term phosphorus deficiency by increasing the expression of related genes such as carbon metabolism, flavonoid synthesis and hormone signal transduction pathways, producing sufficient energy, scavenging ROS, and adjusting plant morphology. However, with the extension of stress duration to 90 days, the expression of genes related to phosphorus cycling and phosphorus recovery (PHT1-4, PHO1 homolog3, PAP) was upregulated, and transcriptional changes and post-transcriptional regulation (miRNA regulation and protein modification) were enhanced to resist long-term phosphorus deficiency stress. In addition, bHLH, MYB, NAC, WRKY and other families also play an important role in regulating gene expression and coping with phosphorus deficiency stress, especially MYB60 negatively regulates flavonoid synthesis pathway, which is significantly down-regulated in leaves treated with phosphorus deficiency for 30 days, thereby promoting the accumulation of flavonoid compounds in leaves.