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Plants engage in a variety of interactions, including sharing nutrients through common mycorrhizal networks (CMNs), which are facilitated by arbuscular mycorrhizal fungi (AMF). These networks can promote the establishment, growth, and distribution of limited nutrients that are important for plant growth, which in turn benefits the entire network of plants. Interactions between plants and microbes in the rhizosphere are complex and can either be socialist or capitalist in nature, and the knowledge of these interactions is equally important for the progress of sustainable agricultural practice. In the socialist network, resources are distributed more evenly, providing benefits for all connected plants, such as symbiosis. For example, direct or indirect transfer of nutrients to plants, direct stimulation of growth through phytohormones, antagonism toward pathogenic microorganisms, and mitigation of stresses. For the capitalist network, AMF would be privately controlled for the profit of certain groups of plants, hence increasing competition between connected plants. Such plant interactions invading by microbes act as saprophytic and cause necrotrophy in the colonizing plants. In the first case, an excess of the nutritional resources may be donated to the receiver plants by direct transfer. In the second case, an unequal distribution of resources occurs, which certainly favor individual groups and increases competition between interactions. This largely depends on which of these responses is predominant ("socialist" or "capitalist") at the moment plants are connected. Therefore, some plant species might benefit from CMNs more than others, depending on the fungal species and plant species involved in the association. Nevertheless, benefits and disadvantages from the interactions between the connected plants are hard to distinguish in nature once most of the plants are colonized simultaneously by multiple fungal species, each with its own cost-benefits. Classifying plant-microbe interactions based on their habitat specificity, such as their presence on leaf surfaces (phyllospheric), within plant tissues (endophytic), on root surfaces (rhizospheric), or as surface-dwelling organisms (epiphytic), helps to highlight the dense and intricate connections between plants and microbes that occur both above and below ground. In these complex relationships, microbes often engage in mutualistic interactions where both parties derive mutual benefits, exemplifying the socialistic or capitalistic nature of these interactions. This review discusses the ubiquity, functioning, and management interventions of different types of plant-plant and plant-microbe interactions in CMNs, and how they promote plant growth and address environmental challenges for sustainable agriculture.
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Interaction: Despite numerous recent insights into neighbor detection and belowground plant communication mediated by root exudates, less is known about the specificity and nature of substances within root exudates and the mechanism by which they may act belowground in root-root interactions. Methods: Here, we used a coculture experiment to study the root length density (RLD) of tomato (Solanum lycopersicum L.) grown with potato onion (Allium cepa var. aggregatum G. Don) cultivars with growth-promoting (S-potato onion) or no growth-promoting (N-potato onion) effects. Results and Discussion: Tomato plants grown with growth-promoting potato onion or its root exudates increased root distribution and length density oppositely and grew their roots away as compared to when grown with potato onion of no growth-promoting potential, its root exudates, and control (tomato monoculture/distilled water treatment). Root exudates profiling of two potato onion cultivars by UPLC-Q-TOF/MS showed that L-phenylalanine was only found in root exudates of S-potato onion. The role of L-phenylalanine was further confirmed in a box experiment in which it altered tomato root distribution and forced the roots grow away. In vitro trial revealed that tomato seedlings root exposed to L-phenylalanine changed the auxin distribution, decreased the concentration of amyloplasts in columella cells of roots, and changed the root deviation angle to grow away from the addition side. These results suggest that L-phenylalanine in S-potato onion root exudates may act as an "active compound" and trigger physio-morphological changes in neighboring tomato roots.
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Terrestrial plants can affect the growth and health of adjacent plants via interspecific interaction. Here, we studied the mechanism by which plant root exudates affect the recruitment of the rhizosphere microbiome in adjacent plants-with implications for plant protection-using a tomato (Solanum lycopersicum)-potatoonion (Allium cepa var. agrogatum) intercropping system. First, we showed that the intercropping system results in a disease-suppressive rhizosphere microbiome that protects tomato plants against Verticillium wilt disease caused by the soilborne pathogen Verticillium dahliae. Second, 16S rRNA gene sequencing revealed that intercropping with potatoonion altered the composition of the tomato rhizosphere microbiome by promoting the colonization of specific Bacillus sp. This taxon was isolated and shown to inhibit V. dahliae growth and induce systemic resistance in tomato plants. Third, a belowground segregation experiment found that root exudates mediated the interspecific interaction between potatoonion and tomato. Moreover, experiments using split-root tomato plants found that root exudates from potatoonion, especially taxifolin-a flavonoid compound-stimulate tomato plants to recruit plant-beneficial bacteria, such as Bacillus sp. Lastly, ultra-high-pressure liquid chromatography-mass spectrometry analysis found that taxifolin alters tomato root exudate chemistry; thus, this compound acts indirectly in modulating root colonization by Bacillus sp. Our results revealed that this intercropping system can improve tomato plant fitness by changing rhizosphere microbiome recruitment via the use of signaling chemicals released by root exudates of potatoonion. This study revealed a novel mechanism by which interspecific plant interaction modulates the establishment of a disease-suppressive microbiome, thus opening up new avenues of research for precision plant microbiome manipulations.
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Microbiota , Solanum lycopersicum , Rizosfera , RNA Ribossômico 16S , Bactérias , Plantas/genética , Exsudatos e Transudatos , Raízes de Plantas/microbiologia , Exsudatos de Plantas/químicaRESUMO
Although magnesium rechargeable batteries (MRBs) have gained considerable attention, research relating to MRBs is still in its infancy. One issue is that magnesium ions are difficult to reversibly (de)intercalate in most electrode materials. Among various available cathodes, VO2(B) is a promising layered cathode material for use in MRBs. Totally different from monolayer VO2, the magnesiation mechanism in monoclinic bulk VO2(B) has not been clearly clarified to this day. For the first time, we systematically investigated the influence of magnetism and van der Waals (vdW) forces on the electronic structure and diffusion kinetics of magnesium in bulk VO2(B) using a series of DFT+U calculations. The Mg diffusivity can reach a high value of 1.62 × 10-7 cm2 s-1 at 300 K, which is comparable to Li+. These results demonstrate that VO2(B) is a potential host material with high mobility and fast kinetics.
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Due to high safety and excellent rate performance, the aqueous Zn-ion battery is a promising energy storage battery for practical application. However, most manganese-based compounds suffer from poor cycling and rate performance. Herein, a new concept of Zn-ions battery is assembled with the loofah-like LaMnO3 perovskite as a novel cathode, achieving fast ion kinetics through the co-intercalation of Zn2+ and H+ cations. In this work, the Ni-doping strategy is adopted to improve the electrochemical performance of LaMnO3 perovskite as a cathode material for Zn-ion batteries. The resultant LaNixMn1-xO3 (x = 0.2) exhibits a superior capacity of 226 mAh g-1 after 80 cycles at 100 mA g-1 and high working voltages at 1.4 V and 1.26 V vs. Zn2+/Zn in the electrolyte of 2 M ZnSO4 + 0.2 M MnSO4. Even at 500 mA g-1, the new Zn/LaNixMn1-xO3 battery still delivers a discharge capacity of 113 mAh g-1 after 1000 cycles. At medium current density, the electrochemical process of the LaNixMn1-xO3 (x = 0.2) electrode is co-controlled by the solid diffusive and surface-capacitive process with a fast ion diffusion rate. The lanthanum manganese perovskite is a potential cathode material for Zn-ion batteries with long cycle performance and high rate cyclability. This work significantly opens up the way of perovskite materials as new cathodes for high-rate ZIBs.
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The application of biochar stimulates the activities of microorganisms that affect soil quality and plant growth. However, studies on the impacts of biochar mainly focus on a monoculture, its effects on interspecific interactions are rarely reported. Here, we investigated the impacts of biochar on tomato/potato-onion intercropped (TO) in a pot experiment. Tomato monoculture (T) and TO were treated with no, 0.3, 0.6, and 1.2% biochar concentrations in a pot experiment. Microbial communities from tomato rhizosphere soil were analyzed by quantitative PCR and Illumina MiSeq. The results showed that compared with the tomato monoculture, 0.6%TO and 1.2%TO significantly increased tomato yield in 2018. TO and 1.2%TO significantly increased plant height and dry weight in 2018 and 2019. Biochar treatments increased soil pH, decreased NO 3 - -N and bulk density, and increased the absorption of N, P, and K by tomato. Bacterial and fungal abundances increased with an increase in biochar concentration, while Bacillus spp. and Pseudomonas spp. abundances showed an "increase-decrease-increase" trend. Biochar had a little effect on bacterial diversities but significantly lowered fungal diversities. TO, 0.6%TO, and 1.2%TO increased the potentially beneficial organisms (e.g., Pseudeurotium and Solirubrobacter) and lowered the potentially pathogenic organisms (e.g., Kribbella and Ilyonectria). Different concentrations of biochar affected the bacterial and fungal community structures. Redundancy analysis indicated that the bacterial community was strongly correlated with soil pH, NO 3 - -N, and EC, while the fungal community was closely related to soil NO 3 - -N and moisture. The network analysis showed that biochar and intercropping affected the symbiosis pattern of the microorganisms and increased the proportion of positive interactions and nitrifying microorganisms (Nitrospirae) in the microbial community. Overall, our results indicated that monoculture and intercropping with biochar improved soil physicochemical states and plant nutrient absorption, and regulated soil microbial communities, these were the main factors to promote tomato growth and increase tomato productivity.
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Paddy-upland rotation is an effective agricultural management practice for alleviating soil sickness. However, the effect of varying degrees of flooding on the soil microbial community and crop performance remains unclear. We conducted a pot experiment to determine the effects of two soil water content (SWC) and two flooding durations on the soil microbial community attributes and yield in cucumber. In the pot experiment, cucumber was rotated with cress single (45 days) or double (90 days) under 100 or 80% SWC. Then, the soil microbial were inoculated into sterilized soil to verified the relationship between cucumber growth and microorganisms. The results indicated single cress rotation resulted in a higher cucumber yield than double cress rotation and control. Cress rotation under 80% SWC had higher soil microbial diversity than cress rotation under 100% SWC and control. Flooding duration and SWC led to differences in the structure of soil microbial communities. Under 80% SWC, single cress rotation increased the relative abundance of potentially beneficial microorganisms, including Roseiflexus and Pseudallescheria spp., in cucumber rhizosphere. Under 100% SWC, single cress rotation increased the relative abundance of potentially beneficial bacteria, such as Haliangium spp., and decreased potential pathogenic fungi, such as Fusarium and Monographella spp., compared with double cress rotation and control. Varying degrees of flooding were causing the difference in diversity, structure and composition of soil microbial communities in the cucumber rhizosphere, which have a positive effect on cucumber growth and development.
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Intercropping can achieve sustainable agricultural development by increasing plant diversity. In this study, we investigated the effects of tomato monoculture and tomato/potato-onion intercropping systems on tomato seedling growth and changes of soil microbial communities in greenhouse conditions. Results showed that the intercropping with potato-onion increased tomato seedling biomass. Compared with monoculture system, the alpha diversity of soil bacterial and fungal communities, beta diversity and abundance of bacterial community were increased in the intercropping system. Nevertheless, the beta-diversity and abundance of fungal community had no difference between the intercropping and monoculture systems. The relative abundances of some taxa (i.e., Acidobacteria-Subgroup-6, Arthrobacter, Bacillus, Pseudomonas) and several OTUs with the potential to promote plant growth were increased, while the relative abundances of some potential plant pathogens (i.e., Cladosporium) were decreased in the intercropping system. Redundancy analysis indicated that bacterial community structure was significantly influenced by soil organic carbon and pH, the fungal community structure was related to changes in soil organic carbon and available phosphorus. Overall, our results suggested that the tomato/potato-onion intercropping system altered soil microbial communities and improved the soil environment, which may be the main factor in promoting tomato growth.
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Sub-optimal temperatures can adversely affect tomato (Solanum lycopersicum) growth, and K+ plays an important role in the cold tolerance of plants. However, gene expression and K+ uptake in tomato in response to sub-optimal temperatures are still not very clear. To address these questions, one cold-tolerant tomato cultivar, Dongnong 722 (T722), and one cold-sensitive cultivar, Dongnong 708 (S708), were exposed to sub-optimal (15/10 °C) and normal temperatures (25/18 °C), and the differences in growth, K+ uptake characteristics and global gene expressions were investigated. The results showed that compared to S708, T722 exhibited lower reduction in plant growth rate, the whole plant K+ amount and K+ net uptake rate, and T722 also had higher peroxidase activity and lower K+ efflux rate under sub-optimal temperature conditions. RNA-seq analysis showed that a total of 1476 and 2188 differentially expressed genes (DEGs) responding to sub-optimal temperature were identified in S708 and T722 roots, respectively. Functional classification revealed that most DEGs were involved in "plant hormone signal transduction", "phenylpropanoid biosynthesis", "sulfur metabolism" and "cytochrome P450". The genes that were significantly up-regulated only in T722 were involved in the "phenylpropanoid biosynthesis" and "plant hormone signal transduction" pathways. Moreover, we also found that sub-optimal temperature inhibited the expression of gene coding for K+ transporter SIHAK5 in both cultivars, but decreased the expression of gene coding for K+ channel AKT1 only in S708. Overall, our results revealed the cold response genes in tomato roots, and provided a foundation for further investigation of mechanism involved in K+ uptake in tomato under sub-optimal temperatures.
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Understanding soil microbial communities in agroecosystems has the potential to contribute to the improvement of agricultural productivity and sustainability. Effects of conversion from long-term wheat plantation to Jerusalem artichoke (JA) plantation on soil fungal communities were determined by amplicon sequencing of total fungal ITS regions. Quantitative PCR and PCR-denaturing gradient gel electrophoresis were also used to analyze total fungal and Trichoderma spp. ITS regions and Fusarium spp. Ef1α genes. Results showed that soil organic carbon was higher in the first cropping of JA and Olsen P was lower in the third cropping of JA. Plantation conversion changed soil total fungal and Fusarium but not Trichoderma spp. community structures and compositions. The third cropping of JA had the lowest total fungal community diversity and Fusarium spp. community abundance, but had the highest total fungal and Trichoderma spp. community abundances. The relative abundances of potential fungal pathogens of wheat were higher in the wheat field. Fungal taxa with plant growth promoting, plant pathogen or insect antagonistic potentials were enriched in the first and second cropping of JA. Overall, short-term conversion from wheat to JA plantation changed soil fungal communities, which is related to changes in soil organic carbon and Olsen P contents.
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Fungos , Helianthus/microbiologia , Microbiologia do Solo , Triticum , Agricultura , Biodiversidade , Fungos/classificação , Fungos/genética , Helianthus/crescimento & desenvolvimento , Metagenoma , Metagenômica/métodos , Triticum/crescimento & desenvolvimento , Triticum/microbiologiaRESUMO
Endoplasmic reticulum protein 29 (ERp29) is an ER luminal protein that has a role in protein unfolding and secretion, but its role in cancer is unclear. Recently, we reported that overexpression of ERp29 significantly inhibited cell proliferation and prevented tumorigenesis in highly proliferative MDA-MB-231 breast cancer cells. Here, we show that ERp29-induced cancer cell growth arrest is modulated by the interplay between the concomitant phosphorylation of p38 and upregulation of the inhibitor of the interferon-induced, double-stranded RNA-activated protein kinase, p58(IPK). In this cell model, ERp29 overexpression significantly downregulates modulators of cell proliferation, namely urokinase plasminogen activator receptor, ß(1)-integrin and epidermal growth factor receptor. Furthermore, ERp29 significantly (P<0.001) increases phosphorylation of p38 (p-p38) and reduces matrix metalloproteinase-9 secretion. The role of ERp29 in upregulating cyclin-dependent kinase inhibitors (p15 and p21) and in downregulating cyclin D(2) is demonstrated in slowly proliferating ERp29-overexpressing MDA-MB-231 cells, whereas the opposite response was observed in ERp29-knockdown MCF-7 cells. Pharmacological inhibition of p-p38 downregulates p15 and p21 and inhibits eIF2α phosphorylation, indicating a role for p-p38 in this process. Furthermore, p58(IPK) expression was increased in ERp29-overexpressing MDA-MB-231 cells and highly decreased in ERp29-knockdown MCF-7 cells. This upregulation of p58(IPK) by ERp29 suppresses the activation of p-p38/p-PERK/p-eIF2α by repressing eIF2α phosphorylation. In fact, reduction of p58(IPK) expression by RNA interference stimulated eIF2α phosphorylation. The repression of eIF2α phosphorylation by p58(IPK) prevents ERp29-transfected cells from undergoing ER-dependent apoptosis driven by the activation of ATF4/CHOP/caspase-3. Hence, the interplay between p38 phosphorylation and p58(IPK) upregulation has key roles in modulating ERp29-induced cell-growth arrest and survival.