Visualizing polymeric components that define distinct root barriers across plant lineages

ABSTRACT Hydrophobic cell wall depositions in roots play a key role in plant development and interaction with the soil environment, as they generate barriers that regulate bidirectional nutrient flux. Techniques to label the respective polymers are emerging, but are efficient only in thin roots or sections. Moreover, simultaneous imaging of the barrier constituents lignin and suberin remains problematic owing to their similar chemical compositions. Here, we describe a staining method compatible with single- and multiphoton confocal microscopy that allows for concurrent visualization of primary cell walls and distinct secondary depositions in one workflow. This protocol permits efficient separation of suberin- and lignin-specific signals with high resolution, enabling precise dissection of barrier constituents. Our approach is compatible with imaging of fluorescent proteins, and can thus complement genetic markers or aid the dissection of barriers in biotic root interactions. We further demonstrate applicability in deep root tissues of plant models and crops across phylogenetic lineages. Our optimized toolset will significantly advance our understanding of root barrier dynamics and function, and of their role in plant interactions with the rhizospheric environment.

Accumulation and distribution of chemical elements in plants of Taraxacum officinale Wigg. (Transbaikal Territory)

The paper presents research data on the content of chemical elements in soils and the plant Taraxacumofficinale Wigg., which grows on the territory of the Transbaikal Territory. The content of chemical elements is comparedwith the maximum permissible concentrations. The coefficients of accumulation, root barrier, and translocation arecalculated.

Diversity in root apoplastic barrier deposition in salt treated wild and domesticated barley seedlings

Salt stress causes changes in root apoplastic barriers, such as the endodermis and the exodermis, and these changes are associated with variation in abiotic stress tolerance. We explored variation in root apoplastic barrier traits, O consumption and root and shoot Na and K content in a diverse collection of commercial and wild barley accessions subjected to non-saline (control) and saline treatments. Lignin and suberin deposition in endo- and exo-dermal cell walls varied between the accessions and in response to salt treatments. Twenty-two wild barley accessions formed an exodermis in response to salt treatments, whereas the commercial barley cultivar Barke did not develop an obvious exodermis. Accessions with pronounced root barrier deposition tended to have lower O consumption relative to the accessions with less obvious barriers. Treatment with abscisic acid enhanced suberisation and lead to a pronounced formation of an exodermis in wild barley accessions, whereas treatment with an ethylene precursor had no obvious effect on suberisation. Principal component analysis revealed associations between suberin deposition, root and shoot Na and K, and root respiration. The variation in root apoplastic barrier traits within the barley accessions represents a useful resource for future crop breeding to improve environmental stress tolerance.

Analysis of supply chain resilience barriers in Indian automotive company using total interpretive structural modelling

PurposeThe study tries to identify the barriers influencing supply chain resilience and examine the inter-relationships between them. These relationships are built on the basis of how one barrier drives or is driven by the changes in another barriers.Design/methodology/approachIn the first phase, literature review and with due discussion with experts, the barriers have been identified and shortlisted for an Indian automotive case company. In the second phase, total interpretive structural modelling (TISM) has been applied to examine inter-relationships between the barriers for an Indian automobile case company. Matrice d'impacts croisés multiplication appliquée á un classment (MICMAC) analysis has also been performed to analyse the driving and dependence power of the barriers.FindingsIn total, 11 barriers are identified from the first phase of the study. In the second phase, the TISM digraph is created which qualitatively explains the reason behind how one barrier leads to another. MICMAC analysis classifies these variables in four clusters namely autonomous, linkage, dependent and independent. These clusters characterise the barriers based on their driving and dependent power which helps managers in strategically tackling them while taking understanding from the TISM digraph.Research limitations/implicationsThree research implications can be made from the study. First, a comprehensive definition of supply chain which helps in understanding of resilience based on disruption phases and recovery. Second, 11 barriers are identified which hinder resilience in automotive sector. Their relationships are modelled using TISM which also gives why a particular relationship exists. Last, MICMAC analysis classifies barriers based on how high or low the driving and dependence power exists.Practical implicationsThe study offers significant implications for supply chain managers helping them in building resilience by identifying barriers and reducing their effect. Barriers are identified for case company which might help managers to tackle them during disruptions. The final TISM digraph depicts the “why” between the inter-relationships between the barriers to resilient supply chains. TISM shows that non-commitment of top management is the major root barrier which has been causing the other problems. MICMAC analysis is also performed along with discussion as to how autonomous, linkage, dependent and independent barriers can be tackled to build resilience.Originality/valueTISM is considered as an effective methodology for conceptual framework development as it also explains “why” between the relationships besides explaining the “what” as against ISM. Identification and understanding of barriers and their interrelationship will help supply chain managers to analyse the influence and inter-dependence of barriers on the resilience of the supply chain. Such understanding will help in mitigating/averting these barriers hence improving the resilience capability. It also adds to the knowledge base in the area of supply chain resilience where several authors have pointed the lack of research.

Structural Modeling and Analysis of Barriers Encountered in Gamification Applications in Health

Applications (apps) offer outstanding opportunities for healthcare services to serve individuals in areas that do not involve technology that improve healthcare outcomes, and that strengthen community health. These opportunities are becoming more common, especially with the increasing use of mobile devices in many segments of society. On the other hand, there are many obstacles that directly or indirectly affect the process of implementing gamification applications. In this study, the authors use Interpretive structural modeling (ISM) and MICMAC aiming to reveal the relations of obstacles encountered, and also to find the root cause of barriers in gamification engagement through applications used in healthcare. Findings showed that the lack of functionality of the apps, having the highest driving power and lowest dependency, was determined as the root barrier whilst other barriers are also divided into levels.

Root Contact between Maize and Alfalfa Facilitates Nitrogen Transfer and Uptake Using Techniques of Foliar 15N-Labeling

Belowground nitrogen (N) transfer from legumes to non-legumes provides an important N source for crop yield and N utilization. However, whether root contact facilitates N transfer and the extent to which N transfer contributes to crop productivity and N utilization have not been clarified. In our study, two-year rain shelter experiments were conducted to quantify the effect of root contact on N transfer in a maize/alfalfa intercropping system. N transfer occurred mainly one direction from alfalfa to maize during the growth period. Following the N0 treatment, the amount of N transfer from alfalfa to maize was 204.56 mg pot−1 with no root barrier and 165.13 mg pot−1 with a nylon net barrier, accounting for 4.72% and 4.48% of the total N accumulated in maize, respectively. Following the N1 treatment, the amount of N transfer from alfalfa to maize was 197.70 mg pot−1 with no root barrier and 139.04 mg pot−1 with a nylon net barrier, accounting for 3.64% and 2.36% of the total N accumulated in the maize, respectively. Furthermore, the amount of N transfer without no root barrier was 1.24–1.42 times higher than that with a nylon net barrier regardless of the level of N addition. Our results highlight the importance and the relevance of root contact for the enhancement of N transfer in a maize/alfalfa intercropping system.

Characterization of Biofilm Formed by Phenanthrene-Degrading Bacteria on Rice Root Surfaces for Reduction of PAH Contamination in Rice

One effective method in to reduce the uptake of organic contaminants by plants is the development of a root barrier. In this study, the characterization of biofilm structure and function by phenanthrene-degrading Pseudomonas sp. JM2-gfp on rice root surfaces were carried out. Our results showed that root surfaces from three rice species, namely Liaojing401, Koshihikari, and Zhenzhuhong all present hydrophobicity and a high initial adhesion of strain JM2-gfp. Matured robust biofilm formation occurred at 48 h on the root surfaces. The biofilm exhibited cell dense aggregates and biomass embedded in the extracellular polymeric substance (EPS) matrix. EPS composition results showed that the proteins, carbohydrates, lipids and nucleic acids are produced in the biofilm, while the content varied with rice species. Under the initial concentration of phenanthrene 50 mg·L−1, the residual phenanthrene in plant roots from ‘Zhengzhuhong’, ‘Koshihikari’ and ‘Liaojing401’ with biofilm mediated were significantly decreased by 71.9%, 69.3% and 58.7%, respectively, compared to those without biofilm groups after 10 days of exposure. Thus, the biofilm colonized on roots plays an important role of degradation in order to reduce the level of phenanthrene uptake of plants. Thereby, the present work provides significant new insights into lowering the environmental risks of polycyclic aromatic hydrocarbons (PAHs) in crop products from contaminated agriculture soils.