Root Research Articles

Effect of magnetic field on growth and protein concentration in aboveground herbage of field pea (Pisum sativum L.) cultivars

Research of the exposure of young pea (Pisum sativum L.) plants of two cultivars (Gold and Uran) to magnetic field (MF) of different flux densities (250 and 350 mT) was conducted in controlled conditions during 20 days. Pea plants were continuously exposed to magnetic field of neodymium magnets. Upon the statistical analysis there were revealed significant effects of MF treatments (P 0.01) on root freshweight, aboveground herbage freshweight and total plant freshweight. Cultivars differed in root (P 0.05), stem (P 0.01) and total plant length (P 0.05). There was also revealed significant Treatment × Cultivar interaction for all the tested traits.

The Role of Sudanese Forests Agro-ecosystem in Improving the Cation Exchange Capacity and Exchangeable Bases of a Sandy Soil in Western Burkina Faso

The objective of this study is to evaluate the influence of Sudanese forests on the chemical equilibrium and exchangeable bases of sandy soils in the Bondoukuy region. The study examines the impact of forest cover on soil fertility and the mechanisms through which these natural ecosystems promote soil health and productivity in the region. The Cation Exchange Capacity (CEC) of soil represents its capacity to retain and exchange nutrient cations with plant roots. In Sudanian Forests Agro-ecosystem, sandy soils are characterized by a dominance of coarse particles, which exhibit a low specific surface area and low cation retention capacity, in contrast to clayey soils. A low CEC restricts soil fertility and the capacity of the soil to sustainably provide essential nutrients to plants. It was hypothesized that the CEC of the topsoil in forests of western Burkina Faso would demonstrate a significant increase due to substantial environmental changes during the fallow period. To test this hypothesis, a comparison was made between soil fertility in forests and fallows, and that of cultivated plots, which were considered the control for this increase. A total of 15 plots were selected, with five plots allocated to each situation. The vegetation and soil of the plots were described in detail. Composite soil samples were taken from the 0-20 cm horizon. The soil analyses in the laboratory were conducted on several parameters, including texture, pH-H2O, pH-KCl, carbon, nitrogen, CEC and exchangeable bases. The results of the observations enabled the classification of the soils as tropical ferruginous soils with iron and manganese sesquioxides. The original materials indicate that the soil exhibits sandy properties. This was demonstrated by the granulometric study, which revealed that the soils under investigation exhibited an essentially sandy texture on the surface horizon. This results in a low retention capacity for exchangeable bases. The woody vegetation of the forest exhibits a greater diversity of flora than that of the fallows. This has a significant impact on the enhancement of the CEC, due to the replenishment of the soil with plant debris of varying organic compositions. The overall pH is slightly acidic, with a range of 5.63 to 5.71. The soils of forests exhibit higher concentrations of carbon and nitrogen than those of the fallows and fields. The observation of chemical balances has enabled the identification of forests as an environment conducive to optimal plant nutrition. Overall, forests enhance the CEC and exchangeable bases, despite the values being below the threshold recommended for tropical sandy soils. It is therefore necessary to implement measures to promote sustainable agriculture and enhance agricultural productivity in this region, where soil nutrients are naturally scarce.

Catabolic pathway acquisition by rhizosphere bacteria readily enables growth with a root exudate component but does not affect root colonization.

Horizontal gene transfer (HGT) is a fundamental evolutionary process that plays a key role in bacterial evolution. The likelihood of a successful transfer event is expected to depend on the precise balance of costs and benefits resulting from pathway acquisition. Most experimental analyses of HGT have focused on phenotypes that have large fitness benefits under appropriate selective conditions, such as antibiotic resistance. However, many examples of HGT involve phenotypes that are predicted to provide smaller benefits, such as the ability to catabolize additional carbon sources. We have experimentally simulated the consequences of one such HGT event in the laboratory, studying the effects of transferring a pathway for catabolism of the plant-derived aromatic compound salicyl alcohol between rhizosphere isolates from the Pseudomonas genus. We find that pathway acquisition enables rapid catabolism of salicyl alcohol with only minor disruptions to the existing metabolic and regulatory networks of the new host. However, this new catabolic potential does not confer a measurable fitness advantage during competitive growth in the rhizosphere. We conclude that the phenotype of salicyl alcohol catabolism is readily transferable but is selectively neutral under environmentally relevant conditions. We propose that this condition is common and that HGT of many pathways will be self-limiting because the selective benefits are small.IMPORTANCEHorizontal gene transfer (HGT) is a key process in microbial evolution, but the factors limiting HGT are poorly understood. Aside from the rather unique scenario of antibiotic resistance, the evolutionary benefits of pathway acquisition are still unclear. To experimentally test the effects of pathway acquisition, we transferred a pathway for catabolism of a plant-derived aromatic compound between soil bacteria isolated from the roots of poplar trees and determined the resulting phenotypic and fitness effects. We found that pathway acquisition allowed bacteria to grow using the plant-derived compound in the laboratory, but that this new phenotype did not provide an advantage when the bacteria were reinoculated onto plant roots. These results suggest that the benefits of pathway acquisition may be small when measured under ecologically-relevant conditions. From an engineering perspective, efforts to alter microbial community composition in situ by manipulating catabolic pathways or nutrient availability will be challenging when gaining access to a new niche does not provide a benefit.

Enhancing chickpea growth through arbuscular mycorrhizal fungus inoculation: facilitating nutrient uptake and shifting potential pathogenic fungal communities.

Arbuscular mycorrhizal fungi (AMF) are the most widespread plant symbionts associated with plant roots, and theyperform numerous functions that contribute to plants' health and physiology. However, there are many knowledge gaps in how the interactions between AMF and root mycobiomes influence the performance of the host plants. To this end, we inoculated a local chickpea cultivar grown in agricultural soil under semi-controlled conditions with Rhizophagus irregularis. In addition to examining mycorrhizal colonization, plant biomass, and mineral nutrition, we sequenced the ITS region of the rDNA to assess the chickpea mycobiome and identify key fungal taxa potentially responding to R. irregularis inoculation. Our results showed that inoculation had a positive effect on chickpea biomass and mineral nutrition, especially the total aboveground phosphorus, potassium and sodium contents. Fusarium, Sporomia, Alternaria, and unknown Pleosporales were the most abundant taxa in the roots, while Stachybotris, Penicillum, Fusarium, Ascobolus, an unknown Pleosporales and Acrophialophora were the most abundant in the rhizosphere. Among the ASVs that either were enriched or depleted in the rhizosphere and roots are potential plant pathogens from the genera Didymella, Fusarium, Neocosmospora, and Stagonosporopsis. This study highlights the relevance of AMF inoculation not only for enhancing chickpea growth and mineral nutrition in semi-arid conditions but also for influencing the composition of the plants' fungal community which contributes to improved plant performance and resilience against biotic and abiotic stress.

Heavy metal phytoremediation potential of Cosmos bipinnatus for use in chromium-contaminated regions of Dravyavati River, Jaipur, Rajasthan, India.

Due to their toxicity and permanence, heavy metals pose a significant threat as pollutants. Metals leach into soil from human activities including mining, manufacturing, and farming. Phytoremediation involves removing contaminants from soils using herbaceous plants and trees; it is a cost-effective, non-invasive, and aesthetically pleasing technique. The current research investigated the phytoremediation capacity of Cosmos bipinnatus in soil that had been polluted with chromium (Cr) along the Dravyavati River in Jaipur. The plant uptake of heavy metals was studied for 20, 40, 60, and 80 days of growth in pot and field experiments using atomic absorption spectrophotometry (AAS) to analyze residual heavy metal concentrations in the plant's shoots and roots. Chromium exhibited variation in total absorption by plants depending on the type of treatment. Using the translocation factor, it was observed that after 80 days in Nala soil 80% + wheat husk 20% (H2), the plant's capacity to absorb Cr was equivalent and considerably higher. Nola soil 80% + wheat husk 20%; H2, and Nala soil 70% + wheat husk 30%; H3 were among the treatments with TFs more than 1; however, the BCF values were all lower than 1. Additionally, root uptake was greater than shoot uptake. Thus, at H3 and H2 treatments, C. bipinnatus was determined to be an efficient phytoextractor for Cr, but at other concentrations, it acted as an excluder.

A Seed Endophytic Bacterium Cronobacter dublinensis BC-14 Enhances the Growth and Drought Tolerance of Echinochloa crus-galli

Successful seed germination and plant seedling growth often require association with endophytic bacteria. Barnyard grass (Echinochloa crus-galli (L.) P. Beauv.) is a main weed during rice cultivation and has frequently been found in drought-prone fields such as cornfields in recent years. To determine whether endophytic bacteria enhance the survival chances of barnyard grass in dryland conditions, endophytic bacteria were collected from barnyard grass seeds. An endophytic bacterial strain, BC-14, was selected and confirmed as Cronobacter dublinensis based on its morphology, physiology, biochemistry, and genomic information. Moreover, C. dublinensis BC-14 secreted IAA in the Luria–Bertani broth up to 28.44 mg/L after 5 days; it could colonize the roots of barnyard grass. After the inoculation with seeds or the well-mixed planting soil, the bacterium can significantly increase the root length and plant height of barnyard grass under drought conditions. When comparing with the control group on the 28th day, it can be seen that the bacterium can significantly increase the contents of chlorophyll b (up to 7.58 times) and proline (37.21%); improve the activities of superoxide dismutase, catalase, and peroxidase (36.90%, 51.51%, and 12.09%, respectively); and reduce the content of malondialdehyde around 25.92%, which are correlated to the drought tolerance. The bacterial genomic annotation revealed that it contains growth-promoting and drought-resistant functional genes. In a word, C. dublinensis BC-14 can help barnyard grass suppress drought stress, promote plant growth, and enhance biomass accumulation, which is helpful to interpret the mechanism of weed adaptability in dry environments.

Formation of Apoplastic Barriers to Radial O₂ Loss in Rice Roots: Effects of Low-O₂ and High-Fe Conditions, and the Roles of Suberin, Glycerol Esters, and Iron Plaques.

Lack of O2 and high concentrations of iron (Fe) are common in flooded soils where Rice (Oryza sativa L.) is cultivated. We tested the hypothesis that growing in stagnant or high Fe conditions might induce the formation of apoplastic barriers in roots with different properties and chemical compositions. We measured radial O2 loss (ROL) from intact roots, the chemical composition of roots and the formation of root iron plaques in Fe-sensitive and Fe-tolerant rice genotypes grown in aerated, deoxygenated stagnant solutions or in aerated solutions containing high concentrations of Fe. Roots of plants grown in stagnant conditions developed tight barriers to ROL, while those grown in high Fe conditions developed only partial barriers. Chemical analysis of enzymatically isolated sclerenchyma/exodermal root cells indicated that roots grown in stagnant conditions showed increased amounts of suberin and glycerol esters. In contrast, roots in high Fe conditions showed an increase in suberization along with formation of iron plaques covering the roots. In high Fe conditions, exodermal suberization and the formation of partial ROL barriers were not influenced by the genotype's tolerance to Fe. The amount of O2 diffused from roots is influenced by the various layers that impede O2 diffusion. Specifically, increased amounts of glycerol esters in the suberized exodermis provide the greater resistance to ROL.

Growth and physiological response of Yulu Hippophae rhamnoides to drought stress and its omics analysis

ABSTRACT Hippophae rhamnoides (H. rhamnoides) is the primary tree species known for its ecological and economic benefits in arid and semi-arid regions. Understanding the response of H. rhamnoides roots to drought stress is essential for promoting the development of varieties. One-year-old Yulu H. rhamnoides was utilized as the experimental material, and three water gradients were established: control (CK), moderate (T1) and severe (T2), over a period of 120 days. The phenotypic traits and physiological indies were assessed and analyzed, while the roots were subjected by RNA-Seq transcriptome and Tandem Mass Tags (TMT) proteome analysis. Drought stress significantly reduced the plant height, ground diameter, root biomass and superoxide dismutase activity; however, the main root length increased. In comparison with CK, a total of 5789 and 5594 differential genes, as well as 63 and 1012 differential proteins, were identified in T1 and T2, respectively. The combined analysis of transcriptome and proteome showed that the number of differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) associated with T1, T2 and CK was 28 and 126, respectively, with 7 and 36 genes achieving effective KEGG annotation. In T1 and T2, the differential genes were significantly enriched in the plant hormone signal transduction pathway, but there was no significant enrichment in the protein expression profile. In T2, 38 plant hormone signal transduction function genes and 10 peroxisome related genes were identified. With the increase of drought stress, the combined expression of DEGs and DEPs increased. Yulu H. rhamnoides may allocate more resources toward CAT while simultaneously decreasing SOD and POD to mitigate the oxidative stress induced by drought. Furthermore, the molecular mechanisms underlying plant hormone signal transduction and peroxisome-related genes in the roots of H. rhamnoides were discussed in greater detail.

Effects of two Bacillus velezensis strains isolated from different sources on the growth of Capsicum annum

Microbial inoculants offer an environmentally friendly approach to enhance plant growth and control disease. In this study, two Bacillus velezensis strains, HKSSLJEBR3 (R3) and Ya-1 were isolated from pepper plant roots and tropical rainforest soil, respectively. Both strains exhibited strong antifungal activity against Fusarium oxysporum f. sp. capsici, with inhibition rates of 48.54 ± 0.66% for R3 and 49.35 ± 1.44% for Ya-1. In greenhouse trials, R3 significantly boosted pepper growth, with a 22.12% increase in plant height, 46.44% more leaves, and 56.29% greater fresh weight. These enhancements were likely due to the strong affinity between R3 and pepper plants. Both strains also improved soil quality, with R3 increasing available potassium (AK) by 5.13% and soil organic matter (SOM) by 4.03%, while Ya-1 showed more significant increases. Metagenomic analysis revealed that both strains altered the rhizosphere microbiome, with R3 promoting Pseudomonas and suppressing Fusarium. These results suggest that the R3 strain has strong potential for enhancing pepper growth, improving soil health, and reshaping the rhizosphere microbiome.

Root microbiome of Panax ginseng in comparison with three other medicinal plants in the families of Araliaceae and Apiaceae

The intricate interplay between endophytic microorganisms and plants in the upkeep of biodiversity, the stability of communities, and the operation of ecosystems needs to be more adequately extensive. Although root-associated microbial communities of plants have been revealed for the last decade, the understanding of bacterial and fungal communities associated with the roots of medicinal plants remains elusive. To highlight the importance of Panax ginseng Meyer (PG) in our research, we investigated the root endophytic bacterial and fungal communities of Panax ginseng Meyer (PG), alongside Aralia cordata (AC), Angelica gigas (AG), and Peucedanum japonicum (PJ), utilizing amplicon-based community profiling and advanced bioinformatic methodologies. The study aimed to investigate the root-endophytic microbiota of ginseng and three other medicinal plants and identify similarities in microbiome composition across different plant species and families. Results revealed that root-endophytic bacterial and fungal communities were influenced by plant species and phylogenetic differences at the family level. Differential abundance tests and random forest models showed microbial features within the same plant family. PG had a distinctive microbial profile with significant B1653_o_Enterobacterales and F8_o_Helotiales. PG had a core microbiome, B10_Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, and a more evenly distributed microbial network compared to AG, PJ, and AC. Our research reveals the intricate endophytic microbial communities within the roots of medicinal plants, pinpointing specific taxa that may be pivotal to their medicinal qualities and overall plant health. These insights carry notable implications for future studies, particularly those focused on the endophytes of PG and their secondary metabolites, as they deepen our understanding of plant-microbe interactions and their role in enhancing the plants’ therapeutic potential.

Causal determinism by plant host identity in arbuscular mycorrhizal fungal community assembly

Abstract An assumption in ecology is that plant identity plays a central role in the assembly of root‐colonising arbuscular mycorrhizal (AM) fungal communities. While numerous correlational studies support this notion, with evidence of host selectivity among fungal taxa and host‐specific responses to different AM fungi, empirical demonstrations of host‐driven AM fungal community assembly remain surprisingly limited. We conducted a factorial experiment growing two globally significant crop species, wheat (Triticum aestivum) and sorghum (Sorghum bicolor), with a common pool of AM fungal species, or without AM fungi. We hypothesised strong differences in AM fungal community structure between the two species driven by strong habitat filtering. Plants were harvested at two time points in which we analysed the community structure of AM fungi in the roots, the phylogenetic diversity, and interactions with plant physiological responses. As we expected, there were distinct trajectories in both the composition and phylogenetic diversity of AM fungal communities between the two host plants through time. However, the effect of habitat filtering during community assembly differed between the two species. In sorghum roots, AM fungal communities exhibited increased richness and became more phylogenetically clustered over time. This shift suggests that community assembly was primarily driven by habitat filtering, or selectivity, imposed by the host which was accompanied by significant increases in plant mycorrhizal growth (from 11.83% to 43.67%) and phosphorus responses (from −0.6% to 43.3%). In contrast, AM fungal communities in wheat displayed little change in diversity, remained phylogenetically unstructured, and provided minimal benefits to the host, indicating a more stochastic assembly process with a stronger influence of competitive interactions. As the field looks to understand what determines the distribution of AM fungi and their community composition while simultaneously seeking to utilise AM fungi for ecosystem benefits, it is important to know the extent to which host identity can influence fungal assembly within plant roots. Our results provide empirical support of host‐determinism in AM fungal community assembly and suggest that this determinism is associated with the growth and nutrient benefits provided by the symbiosis to plants. Read the free Plain Language Summary for this article on the Journal blog.

Exploring the function of plant root diffusion barriers in sealing and shielding for environmental adaptation.

Plant roots serve as the primary interface between the plant and the soil, encountering numerous challenges ranging from water balance to nutrient uptake. One of the central mechanisms enabling plants to thrive in diverse ecosystems is the building of apoplastic diffusion barriers. These barriers control the flow of solutes into and out of the roots, maintaining water and nutrient homeostasis. In this Review, we summarize recent advances in understanding the establishment, function and ecological significance of root apoplastic diffusion barriers. We highlight the plasticity of apoplastic diffusion barriers under various abiotic stresses such as drought, salinity and nutrient deficiency. We also propose new frontiers by discussing the current bottlenecks in the study of plant apoplastic diffusion barriers.

Enhancement Effect of Phragmites australis Roots on Soil Shear Strength in the Yellow River Delta

Soil erosion is one of the causes of ecosystem fragility in the Yellow River Delta. Plant roots can improve soil shear strength and effectively prevent soil erosion. However, there are no studies on soil shear strength in the Yellow River Delta. In this study, Phragmites australis (PA) root–soil composites with different root area ratios (RARs) (RARs = 0%, 0.06%, 0.14%, 0.17%, 0.19%, 0.24%, 0.36%) were prototypically sampled from the Yellow River Delta. Direct shear tests of root–soil composites were performed by a ZJ-type (three-speed) strain-controlled direct shear apparatus. The normal stresses were 25, 50, 100, and 200 kPa, and the shear rate was 1.2 mm/min. The results showed that PA roots significantly increased soil shear strength and cohesion with maximum growth rates of 219.0% and 440.1%, respectively. An optimal RAR of 0.14% in the range of 0~0.36% maximized the shear strength and cohesion of the root–soil composites. The internal friction angles of root–soil composites with different RARs did not differ significantly from those of the rootless soil. This indicates that the increase in shear strength was mainly due to an increase in cohesion. In addition, overall shear failure was the primary failure mode of rootless soil, with the roots pulled out of the soil in the root–soil composite failure mode. It is important to note that the root is deflected during shear in the direction opposite to the direction of the shear stress. These findings deepen our understanding of the effect of vegetation roots on soil shear characteristics and provide a scientific basis for the protection of bank slopes, soil and water conservation, and vegetation restoration in the Yellow River Delta.

The role of root dynamics on the climate sensitivity of ecohydrological processes of over- and understory in a semi-arid groundwater-dependent ecosystem

Plant roots connect belowground moisture with aboveground vegetation functionalities, making root plasticity critical for drought resilience. This study employs an enhanced land surface ecohydrological model, Duke Coupled Hydrology Model with Vegetation and Dynamic Roots (DCHM-VDR), to investigate how root dynamics affect vegetation adaptation under a range of climate conditions. DCHM-VDR features a moisture-driven root parameterization that simulates dynamic root profiles and hydraulic redistribution (HR). Applied to a semiarid woodland with groundwater-dependent mesquites and shallow-rooted shrubs, model results compare well against AmeriFlux tower data and capture observed soil moisture patterns tied to root water uptake, including mesquite’s dimorphic root profile and shifts in water source and the direction of HR. Accounting for HR lowers overall water use efficiency (WUE) by more than 50% in the dry season due to release of deep root water uptake to moisten dry soil layers. Dynamic root profiles reduce water demand by avoiding dry soil patches and utilizing moist layers with increased WUE, especially for shrubs. Mesquites with a dimorphic root profile show a 3-fold annual transpiration (Tr) increase from 183 mm to 629 mm/year and reduced HR/Tr from 34% to 6%, along with a small reduction of around 10% for shrubs, reflecting the importance of groundwater sourcing and the codependence of shrubs on mesquite for water stress resilience. Future climate scenarios were examined using the Thermodynamic Global Warming downscaled data. Mesquites and shrubs respond positively to wetter winters, albeit with opposite water use strategies in the drier growing seasons due to different rooting depths and HR modulation of soil moisture. Mesquites increase transpiration by adjusting root fraction, water uptake, and HR closer to the saturated zone, while shrubs reduce transpiration and increase WUE by 17% compared to a decrease of 13% in mesquite WUE under the driest scenario. The intertwined water use strategies of mesquites and shrubs expressed by the root water uptake dynamics determine ecosystem response aboveground under more extreme climate conditions, highlighting the importance of modeling root architecture dynamics and co-adaptive ecohydrological processes in predicting ecosystem responses to climate change.

Identification of new salicylic acid signaling regulators for root development and microbiota composition in plants.

Besides playing a crucial role in plant immunity via the nonexpressor of pathogenesis-related (NPR) proteins, increasing evidence shows that salicylic acid (SA) can also regulate plant root growth. However, the transcriptional regulatory network controlling this SA response in plant roots is still unclear. Here, we found that NPR1 and WRKY45, the central regulators of SA response in rice leaves, control only a reduced sector of the root SA signaling network. We demonstrated that SA attenuates root growth via a novel NPR1/WRKY45-independent pathway. Furthermore, using regulatory network analysis and mutant characterization, we identified a set of new NPR1/WRKY45-independent regulators that conservedly modulate the root development and root-associated microbiota composition in both Oryza sativa (monocot) and Arabidopsis thaliana (dicot) in response to SA. Our results established the SA signaling as a central element regulating plant root functions under ecologically relevant conditions. These results provide new insights to understand how regulatory networks control plant responses to abiotic and biotic stresses.

Application of Ozonated Water to the Roots Increases Growth and Secondary Metabolite Accumulation in Brassicaceae Plants in a Hydroponics System

ABSTRACT This study aimed to analyze changes in growth parameters and secondary metabolites by intermittently applying ozonated water (OW) to the roots of red mustard, leaf mustard, and kale, grown in a nutrient film technique hydroponic system. During the period when the plants were cultivated for 3 weeks, OW at concentrations of 1 and 3 μL·L− 1 was flushed for 0, 1, 2, 4, and 8 minutes, twice a week, for a total of six treatments. In red mustard, the 1 μL·L− 1 OW treatment for 2 minutes resulted in the most significant increases in shoot fresh weight, shoot dry weight, leaf area, and an elevated shoot/root ratio. For leaf mustard, both the 1 and 3 μL·L− 1 treatments led to notable improvements in shoot fresh weight, total glucosinolate (GSL) content, and shoot/root ratio. During the two concentrations of OW, kale exhibited substantial significant increases in total GSL content, total anthocyanin content, total phenolic content, and shoot/root ratio. These results suggest that flushing OW to the plant roots in hydroponics systems, particularly at a concentration of 1 μL·L− 1 applied for 2 minutes, can effectively enhance shoot growth, secondary metabolite synthesis, and the shoot/root ratio in Brassicaceae plants.

A 2-year pure biochar addition enhances soil carbon sequestration and reduces aggregate stability in understory conditions

The enhancement of soil aggregate size and stability is crucial for mitigating climate change and improving carbon sequestration in forest ecosystems. Biochar, derived from rice husks, has been suggested as an effective mean to increase soil carbon storage. However, isolating biochar’s specific effects on soil aggregate formation and carbon sink capacity can be complex due to the overlapping influences of fertilization and understory vegetation cultivation. Our study circumvented these variables by incorporating different amounts of biochar into plantation soil without any additional cultivation or fertilization, conducting a detailed two–year field experiment. The findings revealed that biochar significantly increased the organic carbon content and density in the uncultivated under–forest Ferralsols, thus enhancing its carbon sink function. Intriguingly, while biochar raised the proportion of small soil aggregates (< 0.25 mm) and their organic carbon levels, it decreased the fraction of larger aggregates (> 0.25 mm), adversely affecting soil aggregate stability. These results suggest that biochar may compromise soil aggregate structure and stability in the absence of plant growth. The positive impact of biochar on soil carbon storage was found to depend more on its inherent inert carbon content than on soil type. Moreover, biochar alone was insufficient to increase the quantity of soil macroaggregates without the binding action of plant root exudates. Biochar’s key function appears to be in enhancing the soil aggregate–forming processes facilitated by plant roots and microorganisms. Therefore, for optimal carbon sequestration in forest soils, integrating biochar application with appropriate agricultural practices is advisable.

The role of proline and betaine functionalized zinc oxide nanoparticles as drought stress regulators in Coriandrum sativum: an in vivo study

Drought stress poses a significant environmental challenge that substantially hinders plant growth and agricultural productivity on a global scale. This stress disrupts water uptake, moderates photosynthetic efficiency, and induces oxidative stress in plants, resulting in considerable yield reductions. Recent advancements in nanotechnology present promising approaches to enhance plant resilience against abiotic stresses. To study the influence of drought stress on vegetative growth of coriander plants and its mitigation by zinc oxide nanoparticles (ZnO NPs) coupled with proline (ZnO-P) and betaine (ZnO-B), a pot experiment was designed. Plants were exposed to drought stress and treated with 50 mg/kg and 100 mg/kg ZnO NPs, ZnO-P, and ZnO-B NPs (ZnO nanocomposites). Plants were watered on wilting. It was observed that in control drought stress plants, the pots were irrigated 8–10 times while the watering requirement reduced for 5–6 time to the plants when fertilized with ZnO nanocomposites. Significant improvement in vegetative parameters (length and weight) was observed under ZnO nanocomposites treatment. At 50 mg/kg of ZnO-P NPs, shoot length increased up to 71% while root length increased up to 24%. Shoot and root fresh weight was improved (5 g and 1.5 g, respectively) at 50 mg/kg of ZnO-P NPs. The total phenolics and flavonoid contents that were increased in drought stress plants, significantly decreased both in roots and shoots of ZnO nanocomposites. Ttotal antioxidant and total reducing power responses also remarkably decreased in shoots of ZnO nanocomposites while in roots the variation was inconsistent. The free radical scavenging potential was also variable in both shoots and roots of coriander plants. Decrease in super oxide and per oxide dismutase activities (up to 33% and 32%, respectively) were observed when pots were added with ZnO nanocomposites. The findings demonstrate that drought stress can be reduced by applying proline and betaine doped ZnO nanoparticles as fertilizer that mitigate the drought condition, strengthen the plants against stress, and also reduces the watering time to the crops to save water. Future research could explore the molecular mechanisms underlying these effects and evaluate the efficacy of ZnO nanocomposites in other crop species and under field conditions to further validate their potential for widespread agricultural use.

Utilization of Polygala paniculata L. Plants as Traditional Medicine by the Community of Borani Langa Village, Ngada Regency

Medical plants are types of plants that have medical benefits for humans and are commonly found in the surrounding environment and in forests. The plant Polygala paniculata L., also known as the fragrant root plant, is widely found in the Ngada Regency area. Polygala paniculata L. typically grows in yards, gardens, and along roadsides. Considering the strong relationship of the community with cultural traditions and the basic need of the community to use medicinal plants to cure various diseases, the utilization of medicinal plants in the community will continue to increase. This research aims to determine the benefits of the Polygala paniculata L. plant as a traditional medicinal plant in the yards and gardens of the Borani Langa Village community in Ngada Regency, as not many people or the community are aware of the benefits or efficacy of this plant. The method used is a qualitative descriptive method. The research was conducted through observation in Borani Langa Village, Ngada Regency. The results of the study indicate that the people of Borani Langa Village, Ngada Regency, are aware of the medicinal properties of the Polygala paniculata L. plant as traditional medicine. The part of the Polygala paniculata L. plant that is effective in curing certain types of diseases is the root. The Polygala paniculata L. plant is processed by boiling it with coconut oil until it reaches a boil, then cooling it down and storing it in a clean bottle. The way to utilize the Polygala paniculata L. plant is by massaging the painful area and applying it to the nose. As a traditional medicine, Polygala paniculata L. can cure diseases such as flu, pain, and muscle aches.

Regulation and function of a polarly localized lignin barrier in the exodermis

AbstractMulticellular organisms control environmental interactions through specialized barriers in specific cell types. A conserved barrier in plant roots is the endodermal Casparian strip (CS), a ring-like structure made of polymerized lignin that seals the endodermal apoplastic space. Most angiosperms have another root cell type, the exodermis, that is reported to form a barrier. Our understanding of exodermal developmental and molecular regulation and function is limited as this cell type is absent from Arabidopsis thaliana. We demonstrate that in tomato (Solanum lycopersicum), the exodermis does not form a CS. Instead, it forms a polar lignin cap (PLC) with equivalent barrier function to the endodermal CS but distinct genetic control. Repression of the exodermal PLC in inner cortical layers is conferred by the SlSCZ and SlEXO1 transcription factors, and these two factors genetically interact to control its polar deposition. Several target genes that act downstream of SlSCZ and SlEXO1 in the exodermis are identified. Although the exodermis and endodermis produce barriers that restrict mineral ion uptake, the exodermal PLC is unable to fully compensate for the lack of a CS. The presence of distinct lignin structures acting as apoplastic barriers has exciting implications for a root’s response to abiotic and biotic stimuli.