Combined dynamic transcriptome and flavonoid metabolome reveal the role of Mo nanoparticles in the nodulation process in soybean.

Symbiotic nitrogen fixation can reduce the impact of agriculture on the environment by reducing fertilizer input. The rapid development of nanomaterials in agriculture provides a new prospect for us to improve the biological nitrogen fixation ability of leguminous crops. Molybdenum is an important component of nitrogenase, and the potential application of MoO3NPs in agriculture is largely unexplored. In this study, on the basis of verifying that MoO3NPs can improve the nitrogen fixation ability of soybean, the effects of MoO3NPs on the symbiotic nitrogen fixation process of soybean were investigated by using dynamic transcriptome and targeted metabolome techniques. Here we showed that compared with conventional molybdenum fertilizer, minute concentrations of MoO3NPs (0.01-0.1 mg kg-1) could promote soybean growth and nitrogen fixation efficiency. The nodules number, fresh nodule weight and nitrogenase activity of 0.1 mg kg-1 were increased by 17 %, 14 % and 27 %, and plant nitrogen accumulation increased by 17 %. Compared with conventional molybdenum fertilizer, MoO3NPs had a greater effect on apigenin, kaempferol and other flavonoid, and the expression of nodulation related genes such as ENOD93, F3'H. Based on WGCNA analysis, we identified a core gene GmCHS9 that was positively responsive to molybdenum and was highly expressed during MoO3NPs induced nodulation. MoO3NPs could improve the nitrogen fixation ability of soybean by promoting the secretion of flavonoids and the expression of key genes. This study provided a new perspective for the nano-strengthening strategy of nodules development and flavonoid biosynthesis by molybdenum.

Clinical Outcomes and Medical Burdens of Neonatal Arrhythmias in Children's Hospitals in China: A Protocol for Multi-Center Retrospective Cohort Study.

Neonatal arrhythmias are significant contributors to infant mortality. Timely diagnosis and treatment are essential for neonates with non-benign arrhythmias to avoid severe complications, and ongoing treatment and follow-up are sometimes needed. The main objective of this study will be to understand the incidence and demographic characteristics of arrhythmias in hospitalized neonates in China and the related factors of outcomes. A secondary objective will be to establish the first follow-up system for neonatal arrhythmias in China. The medical burdens of neonatal arrhythmias in China will also be investigated. The data from the Futang Research Center of Pediatric Development (FRCPD) database between January 2016 and December 2021 were obtained. Newborns admitted to member hospitals with a discharge diagnosis of "neonatal arrhythmia" (ICD-10 code P29.151) or "arrhythmia" (ICD-10 code I49.904) were included. The medical record information was collected and classified into two groups: heart failure and non-heart failure. The differences between the two groups and independent risk factors for neonatal arrhythmias complicated with heart failure were analyzed. In addition, a follow-up study of patients discharged from Beijing Children's Hospital was conducted to evaluate their outcomes at the age of 3 years old. Factors influencing hospitalization costs were analyzed using rank-sum tests and multiple linear regression. It is anticipated that the study findings will provide new and comprehensive data on the health needs of neonatal arrhythmias in China. The study will establish the first follow-up system for neonatal arrhythmias in China. This study will help reduce the burden of patients and their families as well as the society.

Effects of molybdenum supply on microbial diversity and mineral nutrient availability in the rhizosphere soil of broad bean (Vicia Faba L.).

Molybdenum application holds the potential to enhance agricultural productivity. However, the precise impact on soil microbial diversity and mineral nutrient availability remains uncertain. In this study, we collected rhizosphere soil samples from different growth stages of broad beans. By analyzing mineral element contents, soil phosphorus and zinc fractions, as well as fungal and bacterial diversity, we observed that Mo application resulted in a reduction of soil Citrate‒P and HCl‒P content. This reduction led to an increase in available P content at different stages. Moreover, Mo application elevated root P concentration, but concurrently impeded the translocation of P to the shoots. Mo application also decreased the soil Exc‒Zn (exchangeable Zn) content while increasing the Res‒Zn (residual Zn) content, ultimately causing a decrease in available Zn content at different stages. Consequently, the Zn concentration within broad beans correspondingly decreased. Mo application fostered an augmentation in fungal richness and Shannon indices at the branching and podding stages. The analysis of microbial co-occurrence networks indicated that Mo application bolstered positive connectivity among fungal taxa. Remarkably, Mo significantly increased the abundance of Chaetomium, Leucosporidium, and Thielavia fungi. Spearman correlation analysis demonstrated a significant positive correlation between fungal diversity and soil available P content, as well as a notable negative correlation with soil available Zn content. These findings suggest that Mo application may modify the availability of soil P and Zn by influencing fungal diversity in the rhizosphere of crop soil, ultimately impacting nutrient accumulation within the grains.

Magnesium accelerates changes in the fruit ripening and carotenoid accumulation in Satsuma Mandarin pulp.

This study aims to further examine the effect of Magnesium (Mg) application on fruit quality and carotenoid metabolism in Satsuma mandarin pulp. For this, a field experiment was using 20-year-old Satsuma mandarin (C. unshiu Marc.) for two treatment; (1) CK treatment (without Mg), (2) Mg fertilizer treatment (200 g MgO plant-1). Compared with CK, Mg treatment substantially raised the Mg content in pulp at 90 to 150 DAF (the fruit expansion period), increasing by 15.69%-21.74%. Mg treatment also increased fruit TSS content by 15.84% and 9.88%, decreased fruit TA content in by 34.25% and 33.26% at 195 DAF and 210 DAF (the fruit ripening period). Moreover, at 120 to 195 DAF, Mg treatment significantly increased the levels of lutein, ß-cryptoxanthin, zeaxanthin and violaxanthin in the pulp. This can be explained by the increased expression of important biosynthetic genes, including CitPSY, CitPDS, CitLCYb1, CitLCYb2, CitLCYe, CitHYb, and CitZEP, that played a role in altering the carotenoid composition. The findings of this research offer a novel approach for augmenting both the economic and nutritional worth of citrus fruits.

Revealing the Mechanistic Basis of Regulation of Phosphorus Uptake in Soybean (Glycine max) Roots by Molybdenum: An Integrated Omics Approach.

While molybdenum (Mo) application can improve phosphorus (P) availability to plants by changing P speciation in the rhizosphere, the mechanistic basis of this process remains unclear. This work investigated the impact of various combinations of Mo and P treatments on root morphology, P and Mo uptake, and root transcriptome and metabolome. Mo application significantly increased soybean biomass and the number of lateral roots at both low (5 µmol) or normal (500 µmol) P levels and significantly improved P concentration and accumulation in Normal P treatment. Compared with the Normal P treatment, Low P significantly increased the number of roots, root surface area, and root acid phosphatase secretion. A total of 6811 Mo-responsive differentially expressed genes and 135 differential metabolites were identified at two P levels. At Low P, transcriptional changes significantly increased root synthesis and secretion of succinic acid, methylmalonic acid, and other organic acids as well as acid phosphatase, thereby increasing the conversion of soil aluminum-bound P and organic P into available P. At Normal P, Mo application increased P uptake mainly by increasing the number of lateral roots. Thus, Mo helps crops adapt to different P levels by regulating root anatomy and transcriptional and metabolic profiles of their roots.

Improving insulin self-injection accuracy in patients with diabetes mellitus through a nursing project.

BACKGROUND: Non-standardized insulin injection has an impact on the efficacy of glucose control. OBJECTIVES: The aim of the study was to explore the effectiveness of a nursing project in improving the insulin self-injection accuracy of diabetes mellitus patients. MATERIAL AND METHODS: A total of 200 type 2 diabetes patients who received insulin therapy with an insulin pen were recruited at the First Affiliated Hospital of Army Medical University (Chongqing, China). Patients were randomly assigned to a control (n = 100) or intervention (n = 100) group. Conventional health education was conducted in the control group, while a nursing project and conventional health education were undertaken in the intervention group. The following parameters were analyzed between the 2 groups: standardized insulin pen use at admission and discharge, glycosylated hemoglobin (HbA1c), time in range (TIR), and adipose hyperplasia incidence rate 6 months after discharge. RESULTS: Concerning standardized insulin self-injection, the intervention group was superior to the control group, and the difference between the 2 groups was statistically significant (p < 0.05). The HbA1c levels (p = 0.000), TIR (p = 0.005) and adipose hyperplasia incidence rate 6 months after discharge (p = 0.000) all improved in the intervention group compared to the control group. CONCLUSIONS: The application of the nursing project effectively improved the efficacy of glucose control in diabetes mellitus patients.

Boron deficiency mediates plant-insect (Diaphorima citri) interaction by disturbing leaf volatile organic compounds and cell wall functions.

Nutritional enhancement has been reported to effectively relieve infected symptoms of Huanglongbing, one of the most destructive diseases of citrus. However, few studies focused on the role of plant nutrition in citrus plant-vector (Asian citrus psyllid; Diaphorina citri Kuwayama) interactions, which is regarded as an important part to develop an effective management strategy. METHOD: In the present study, a hydroponic culture was carried out to evaluate the effects of boron deficiency on psyllid feeding process to decode the molecular/biochemical basis of host-psyllid interaction. RESULTS: Boron deficiency was observed to play a major role in accelerating the release of volatile organic compounds, especially methyl salicylate, affecting the shikimic acid pathway through an elevated synthesis of shikimic acid, l-phenylalanine, 3-phenylpyruvic acid and salicylic acid. These changes made citrus leaf more attractive to psyllid adults. Meanwhile, boron deficiency evidently decreased the boron concentration of leaf cell wall fractions, thereby, weakened the structural stability by affecting pectin and cellulose formations. A significant decrease of cell wall mechanical strength was observed in boron-deficiency leaf, which could be the critical reasons to reduce piercing and to increase phloem ingestion during psyllid feeding. CONCLUSION: Our study demonstrated that boron deficiency facilitated the feeding behavior of psyllid adults through elevated release of methyl salicylate, coupled with weakened mechanical properties of cell wall.

Efficient Variational Bayes Learning of Graphical Models With Smooth Structural Changes.

Estimating a sequence of dynamic undirected graphical models, in which adjacent graphs share similar structures, is of paramount importance in various social, financial, biological, and engineering systems, since the evolution of such networks can be utilized for example to spot trends, detect anomalies, predict vulnerability, and evaluate the impact of interventions. Existing methods for learning dynamic graphical models require the tuning parameters that control the graph sparsity and the temporal smoothness to be selected via brute-force grid search. Furthermore, these methods are computationally burdensome with time complexity O(NP3) for P variables and N time points. As a remedy, we propose a low-complexity tuning-free Bayesian approach, named BASS. Specifically, we impose temporally dependent spike and slab priors on the graphs such that they are sparse and varying smoothly across time. An efficient variational inference algorithm based on natural gradients is then derived to learn the graph structures from the data in an automatic manner. Owing to the pseudo-likelihood and the mean-field approximation, the time complexity of BASS is only O(NP2). To cope with the local maxima problem of variational inference, we resort to simulated annealing and propose a method based on bootstrapping of the observations to generate the annealing noise. We provide numerical evidence that BASS outperforms existing methods on synthetic data in terms of structure estimation, while being more efficient especially when the dimension P becomes high. We further apply the approach to the stock return data of 78 banks from 2005 to 2013 and find that the number of edges in the financial network as a function of time contains three peaks, in coincidence with the 2008 global financial crisis and the two subsequent European debt crisis. On the other hand, by identifying the frequency-domain resemblance to the time-varying graphical models, we show that BASS can be extended to learning frequency-varying inverse spectral density matrices, and further yields graphical models for multivariate stationary time series. As an illustration, we analyze scalp EEG signals of patients at the early stages of Alzheimer's disease (AD) and show that the brain networks extracted by BASS can better distinguish between the patients and the healthy controls.

Recruitment of specific microbes through exudates affects cadmium activation and accumulation in Brassica napus.

Exploration of the mechanisms of cadmium (Cd) activation mediated by the rhizosphere process is important to advance our understanding of Cd accumulation in plants. In this study, two oilseed rape cultivars (L338, L351) with varied Cd accumulation traits were applied and the responses of their rhizosphere ecology to Cd stress were investigated by metabolome and microbiome. The results showed that shoot Cd accumulations in L338 accounted for 54.16% and 64.76% of those in L351 under low and high Cd contamination, respectively. Moreover, the cultivars response of rhizosphere process reflected that the lower pH and higher Cd mobility were assigned to the characters of L351, which were induced by the secretion of carboxylic acid (e.g. Acetaminophen cysteine, N-Fructosyl alliin) and the enrichment of bacterial taxa with the capacities of Cd resistant and activation (e.g. Sphingomonas, Flavobacterium, Neorhizobium, Altererythrobacter). Conclusively, the varied Cd accumulation traits of two oilseed rape cultivars were not only derived from the Cd transfer ability, it would be ascribed to Cd mobility regulated by rhizosphere processes as well. The results provide baseline data and a new perspective on the cultivar response of Cd accumulation, thus maintaining cleaner production of oilseed rape.

Fruit Characteristics of Citrus Trees Grown under Different Soil Cu Levels.

The effects of the increased soil copper (Cu) on fruit quality due to the overuse of Cu agents have been a hot social issue. Seven representative citrus orchards in Guangxi province, China, were investigated to explore the fruit quality characteristics under different soil Cu levels and the relationship between soil-tree Cu and fruit quality. These results showed that pericarp color a value, titratable acid (TA), and vitamin C (Vc) were higher by 90.0, 166.6, and 22.4% in high Cu orchards and by 50.5, 204.2, and 55.3% in excess Cu orchards, compared with optimum Cu orchards. However, the ratio of total soluble solids (TSS)/TA was lower by 68.7% in high Cu orchards and by 61.6% in excess Cu orchards. With the increase of soil Cu concentrations, pericarp color a value and Vc were improved, TA with a trend of rising first then falling, and TSS/TA with a trend of falling first then rising were recorded. As fruit Cu increased, pericarp color a value and TSS reduced and as leaf Cu increased, TSS/TA decreased while Vc was improved. Moreover, a rise in soil Cu enhanced leaf Cu accumulation, and a rise in leaf Cu improved fruit Cu accumulation. Fruit Cu accumulation reduced fruit quality by direct effects, leaf Cu improved fruit quality by direct and indirect effects. Soil Cu affected fruit quality by indirect effects by regulating leaf Cu and fruit Cu. Therefore, reasonable regulation and control of soil Cu concentrations can effectively increase pericarp color, sugar, and acid accumulation in citrus fruit.

Glycyrrhizin Attenuates Hypoxic-Ischemic Brain Damage by Inhibiting Ferroptosis and Neuroinflammation in Neonatal Rats via the HMGB1/GPX4 Pathway.

With unknown etiology and limited treatment options, neonatal hypoxic-ischemic brain damage (HIBD) remains a major cause of mortality in newborns. Ferroptosis, a recently discovered type of cell death triggered by lipid peroxidation, is closely associated with HIBD. High-mobility group box 1 (HMGB1), a molecule associated with inflammation damage, can induce neuronal death in HIBD. However, it remains unknown whether HMGB1 contributes to neuronal ferroptosis in patients with HIBD. Herein, glycyrrhizin (GL), an HMGB1 inhibitor, was used to investigate the relationship between ferroptosis and HMGB1. RAS-selective lethal 3(RSL3), a ferroptosis agonist, was administered to further confirm the changes in the signaling pathway between HMGB1 and ferroptosis. Western blot analysis revealed that GL markedly suppressed the expression of HMGB1 and increased the level of GPX4 in the context of HIBD. We observed changes in neuronal ultrastructure via transmission electron microscopy to further confirm the occurrence of ferroptosis. Real-time PCR indicated that GL inhibited the expression of ferroptosis-related genes and inflammatory factors. Immunofluorescence and immunohistochemistry staining confirmed GL inhibition of neuronal damage and ferroptosis in HIBD associated with GPX4 and ROS. GL not only inhibited ferroptosis induced by RSL3 and oxygen-glucose deprivation in vitro but also inhibited ferroptosis induced by HIBD in vivo. More importantly, GL may improve oxidative stress imbalance and mitochondrial damage, alleviate the downstream production of inflammatory factors, and ultimately reduce ferroptosis and damage to cortical neurons following HIBD via the HMGB1/GPX4 pathway. In conclusion, we showed for the first time that GL could suppress the occurrence of neuronal ferroptosis and reduce neuronal loss in HIBD via the HMGB1/GPX4 pathway. These findings highlight the potential of HMGB1 signaling antagonists to treat neuronal damage by suppressing ferroptosis, provide new and unique insights into GL as a neuroprotective agent, and suggest new prevention and treatment strategies for HIBD.

COVID-19 and Long-Term Outcomes: Lessons from Other Critical Care Illnesses and Potential Mechanisms.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus that is currently causing a pandemic and has been termed coronavirus disease (COVID-19). The elderly or those with preexisting conditions like diabetes, hypertension, coronary heart disease, chronic obstructive pulmonary disease, cerebrovascular disease, or kidney dysfunction are more likely to develop severe cases when infected. Patients with COVID-19 admitted to the ICU have higher mortality than non-ICU patients. Critical illness has consistently posed a challenge not only in terms of mortality but also in regard to long-term outcomes of survivors. Patients who survive acute critical illness including, but not limited to, pulmonary and systemic insults associated with acute respiratory distress syndrome, pneumonia, systemic inflammation, and mechanical ventilation, will likely suffer from post-ICU syndrome, a phenomenon of cognitive, psychiatric, and/or physical disability after treatment in the ICU. Post-ICU morbidity and mortality continue to be a cause for concern when considering large-scale studies showing 12-month mortality risks of 11.8-21%. Previous studies have demonstrated that multiple mechanisms, including cytokine release, mitochondrial dysfunction, and even amyloids, may lead to end-organ dysfunction in patients. We hypothesize that COVID-19 infection will lead to post-ICU syndrome via potentially similar mechanisms as other chronic critical illnesses and cause long-term morbidity and mortality in patients. We consider a variety of mechanisms and questions that not only consider the short-term impact of the COVID-19 pandemic but its long-term effects that may not yet be imagined.

Cadmium-induced changes in composition and co-metabolism of glycerolipids species in wheat root: Glycerolipidomic and transcriptomic approach.

Lipids are the structural constituents of cell membranes and play crucial roles in plant adaptation to abiotic stresses. The aim of this study was to use glycerolipidomic and transcriptomic to analyze the changes in lipids metabolism induced by cadmium (Cd) exposure in wheat. The results indicated that Cd stress did not decrease the concentrations of monogalactosyldiacyglycerol (MGDG), phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and phosphatidic acid at 6 h, but decreased digalactosyldoacylglycerol (DGDG), MGDG, PC, phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylserine (PS) and LPC concentrations in wheat root at 24 h. Although the concentrations of highly abundant glycerolipids PC and PE were decreased, the ratios of PC/PE increased thus contributing to wheat adaptation to Cd stress. Cd did not reduce the extent of total lipid unsaturation due to the unchanged concentrations of high abundance species of C36:4, C34:2, C34:3 and C36:6 at 6 h, indicative of their roles in resisting Cd stress. The correlation analysis revealed the glycerolipids species experiencing co-metabolism under Cd stress, which is driven by the activated expression of genes related to glycerolipid metabolism, desaturation and oxylipin synthesis. This study gives insights into the changes of glycerolipids induced by Cd and the roles in wheat adaptation to Cd stress.

The Role of Pseudomonas aeruginosa Virulence Factors in Cytoskeletal Dysregulation and Lung Barrier Dysfunction.

Pseudomonas (P.) aeruginosa is an opportunistic pathogen that causes serious infections and hospital-acquired pneumonia in immunocompromised patients. P. aeruginosa accounts for up to 20% of all cases of hospital-acquired pneumonia, with an attributable mortality rate of ~30-40%. The poor clinical outcome of P. aeruginosa-induced pneumonia is ascribed to its ability to disrupt lung barrier integrity, leading to the development of lung edema and bacteremia. Airway epithelial and endothelial cells are important architecture blocks that protect the lung from invading pathogens. P. aeruginosa produces a number of virulence factors that can modulate barrier function, directly or indirectly, through exploiting cytoskeleton networks and intercellular junctional complexes in eukaryotic cells. This review summarizes the current knowledge on P. aeruginosa virulence factors, their effects on the regulation of the cytoskeletal network and associated components, and molecular mechanisms regulating barrier function in airway epithelial and endothelial cells. A better understanding of these processes will help to lay the foundation for new therapeutic approaches against P. aeruginosa-induced pneumonia.

Migration of Chlorine in Plant-Soil-Leaching System and Its Effects on the Yield and Fruit Quality of Sweet Orange.

Chlorine (Cl) is indispensable for the growth of plants. While rarely systematic reports are available for the effect of Cl-containing fertilizers on citrus production. This study aimed to investigate the impacts of various Cl-containing fertilizers on the nutrients in the leaves, the yield and quality of sweet orange, and the Cl migration in the plant-soil-leaching system. A 5-year field experiment (2016-2020) with five Cl treatments (0, 75, 150, 450, and 900 kg ha-1), and soil core lysimeter test with five Cl levels (0, 150, 225, 300, and 450 kg ha-1) were carried out. The results showed that 77.0% of Cl leached into above 60 cm deeper soil layer, with calcium as the main accompanying ions, resulting in less Cl being absorbed by the citrus plants. The content of Cl in the leaves and soil was enhanced by the increasing input of Cl-containing fertilizer, without yearly increased characteristics, under a mean annual rainfall of 1,474 mm. Chlorine significantly increased the yield (13.24-37.8 9%), fruit weight, and vitamin C (Vc), in addition to enhancing the flavor and the juice yield of sweet orange via improving the absorption of N and K. Moreover, the long-term application of potassium sulfate has elevated the accumulation of sulfur in the soil and in leaves; it is becoming a potential risk factor for citrus production. Taken together, the application of Cl-containing fertilizer in sweet orange is feasible, and trace absorbance of Cl could improve the yield and fruit quality of sweet orange.

CaMK4 is a downstream effector of the α1G T-type calcium channel to determine the angiogenic potential of pulmonary microvascular endothelial cells.

Pulmonary microvascular endothelial cells (PMVECs) uniquely express an α1G-subtype of voltage-gated T-type Ca2+ channel. We have previously revealed that the α1G channel functions as a background Ca2+ entry pathway that is critical for the cell proliferation, migration, and angiogenic potential of PMVECs, a novel function attributed to the coupling between α1G-mediated Ca2+ entry and constitutive Akt phosphorylation and activation. Despite this significance, mechanism(s) that link the α1G-mediated Ca2+ entry to Akt phosphorylation remain incompletely understood. In this study, we demonstrate that Ca2+/calmodulin-dependent protein kinase (CaMK) 4 serves as a downstream effector of the α1G-mediated Ca2+ entry to promote the angiogenic potential of PMVECs. Notably, CaMK2 and CaMK4 are both expressed in PMVECs. Pharmacological blockade or genetic knockdown of the α1G channel led to a significant reduction in the phosphorylation level of CaMK4 but not the phosphorylation level of CaMK2. Pharmacological inhibition as well as genetic knockdown of CaMK4 significantly decreased cell proliferation, migration, and network formation capacity in PMVECs. However, CaMK4 inhibition or knockdown did not alter Akt phosphorylation status in PMVECs, indicating that α1G/Ca2+/CaMK4 is independent of the α1G/Ca2+/Akt pathway in sustaining the cells' angiogenic potential. Altogether, these findings suggest a novel α1G-CaMK4 signaling complex that regulates the Ca2+-dominated angiogenic potential in PMVECs.

Ionomics analysis provides new insights into the co-enrichment of cadmium and zinc in wheat grains.

Cadmium (Cd) is present in many soils and, when enter a food chain, represents a major health threat to humans. The existent large variation in grain Cd content amongst wheat genotypes opens prospects for genetic improvement for reduced Cd uptake in this species. However, selecting low-Cd-accumulating varieties comes with a possible caveat of affecting uptake other essential nutrients. In this work, we screened 134 wheat varieties in 3 various field studies and selected 15 high- and 15 low-Cd accumulating varieties in grains for ionomics analysis. Our results showed that high-Cd accumulating varieties also possessed an ability to accumulate mineral elements of calcium, magnesium, manganese, iron and zinc, while varieties with low Cd content were deficient in many essential nutrients and, especially, zinc (Zn). The above data was confirmed in an independent trail involving another 97 wheat varieties. Thus, selecting plants for high Zn accumulation (as a part of biofortification programs) resulted in an inadvertent increase in accumulation of the toxic Cd in wheat. Vice versa, selecting low Cd-accumulating varieties comes with a danger of reducing their Zn content, with major consequences to food quality and human health. We suggest that the above conundrum can be resolved by understanding the structure-function relations of various transporters isoforms involved in Zn and Cd transport and issue-specific mode of their operation, via cell-based phenotyping followed by molecular breeding.

Effects of phosphorus on fruit soluble sugar and citric acid accumulations in citrus.

Phosphorus (P) is one of the essential macro-elements for plants. Sugar and organic acid are important factors affecting sensory characteristics of citrus fruit quality. The aim of this study was to investigate how P fertilizer affects quality improvement particularly sucrose (Suc), fructose (Fru), glucose (Glu) and citric acid (CA) accumulations in Cara Cara navel. P fertilizer improved fruit quality of Cara Cara navel, as supported by decreasing titratable acid (TA), CA and increasing soluble solid (TSS), sugars and the ratio of TSS and TA. At the early stage of fruit development, P fertilizer had greater roles in degrading Suc into Fru and Glu due to the increased activities of Suc-degrading enzymes including acid invertase, neutral invertase and Suc synthase-cleavage activity. Coversely, at the mid and late stages of fruit development, P fertilizer had greater roles in re-synthesizing Suc due to the increased activities of Suc-synthesizing enzymes including Suc phosphate synthase and Suc synthase-synthetic activity. These results indicated that application of P fertilizer increased soluble sugars concentrations by improving Suc metabolism and sink strength in fruit conferred by the upregulations of the activities of Suc-degrading and Suc-synthesizing enzymes. P fertilizer decreased CA accumulations at least partially by inhibiting synthesis of CA due to the decreased activities of CA-synthesizing enzymes including citrate synthetase and phosphoenolpyruvate carboxylase. This study suggested that P fertilizer, particularly fertilized with 0.40 kg/plant, increased soluble sugars but decreased CA accumulations in citrus fruit.

Molybdenum induces alterations in the glycerolipidome that confer drought tolerance in wheat.

Molybdenum (Mo), which is an essential microelement for plant growth, plays important roles in multiple metabolic and physiological processes, including responses to drought and cold stress in wheat. Lipids also have crucial roles in plant adaptions to abiotic stresses. The aim of this study was to use glycerolipidomic and transcriptomic analyses to determine the changes in lipids induced by Mo that are associated with Mo-enhanced drought tolerance in wheat. Mo treatments increased the transcript levels of genes involved in fatty acid and glycerolipid biosynthesis and desaturation, but suppressed the expression of genes involved in oxylipin production. Wheat plants supplemented with Mo displayed higher contents of monogalactosyldiacyglycerol (MGDG), digalactosyldoacylglycerol (DGDG), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), and phosphatidylcholine (PC) with increased levels of unsaturation. The levels of MGDG, DGDG, PG, and PC increased under PEG-simulated drought (PSD), and the magnitude of the responses varied in the presence and absence of Mo. Mo increased the accumulation of the most abundant glycerolipid species of C36:6, C34:4, and C34:3 by increasing the expression of genes related to desaturation under PSD, and this contributed to maintaining the fluidity of membranes. In addition, Mo attenuated the decreases in the ratios of DGDG/MGDG and PC/PE that were observed under PSD. These changes in lipids in Mo-treated wheat would contribute to maintaining the integrity of membranes and to protecting the photosynthetic apparatus, thus acting together to enhance drought tolerance.

Biochar is superior to lime in improving acidic soil properties and fruit quality of Satsuma mandarin.

A better understanding is required for using biochar as an alternative option to lime materials for sustainable amelioration of soil acidity and improvement of fruit quality in acidic soils. In this study, a pot experiment was conducted to investigate the comparative effects of biochar (three different dosages of biochar, 1%, 2% and 4%, were denoted by BC-1, BC-2 and BC-3, respectively) and lime (three different dosages of lime, 1.2, 2.4 and 3.6 g kg-1, were denoted by L-1, L-2 and L-3, respectively) on soil properties and fruit acidity of Satsuma mandarin. The decreased rates of fruit titratable acid (TA) by BC-1, BC-2 and BC-3 were 16.18%, 25.00% and 14.71%, which were higher than those by L-1, L-2 and L-3 were 11.76%, 16.18% and 5.88%. Moreover, the increased rates of fruit total soluble solid (TSS)/TA were 14.94%, 31.73%, 28.04% by BC-1, BC-2 and BC-3, but were 11.42%, 21.77%, 10.15% by L-1, L-2 and L-3, suggesting that biochar had better effects on improving fruit quality. Acidic soil properties were improved by biochar and lime, but biochar had better amelioration effects, as evidenced by soil-treated with BC-2 and BC-3 had greater increases of soil pH, soil respiration (SR) and microbial metabolic quotient, activities of soil urease (SU), invertase (SI), catalase (CAT) and cellulose (SC), and concentrations of soil phosphorus (P), potassium (K) and magnesium (Mg). Principal component analysis showed that soil pH, SR, SU, SI and CAT were main contributors to the differences of improvement effects of biochar and lime. Correlation analysis showed that fruit TA had negative relationships with soil pH, SU, SI, CAT, SC and soil P, K, Mg. This study indicates that the better effects of biochar on improving fruit quality of Satsuma mandarin were associated with the greater effects of it on improving acidic soil properties.