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Bacterial wilt caused by Ralstonia solanacearum is a destructive plant disease, particularly in potato (Solanum tuberosum). R. solanacearum deploys a diverse and potent arsenal of type III effectors to inhibit the plant immune system. However, the understanding of individual effectors promoting susceptibility in host plants and interfering with plant immunity responses is still limited. Here, we demonstrated that the type III effector RipV1 functioned as a novel E3 ubiquitin ligase (NEL) effector and exhibited E3 ubiquitin ligase activity in vitro. Transient expression of RipV1 suppressed plant pathogen‐associated molecular pattern (PAMP)‐triggered immunity (PTI) responses in Nicotiana benthamiana, such as the expression of PTI‐related genes and the reactive oxygen species (ROS) burst. Prolonged expression of RipV1 induced cell death in N. benthamiana leaves. Notably, mutating the conserved cysteine residue of RipV1 abolished its E3 ligase activity and its ability to suppress plant PTI responses. This study also revealed the indispensability of RipV1 for R. solanacearum's full virulence in potato. Transgenic potato plants overexpressing ripV1 but not the catalytic mutant ripV1‐C444A displayed enhanced susceptibility to R. solanacearum. RipV1 was observed to localize specifically to the plant plasma membrane, with its N‐terminus being pivotal in determining this localization. These findings showcase that RipV1 acts as a NEL effector and contributes to R. solanacearum virulence by suppressing plant PTI responses through its E3 activity. [ABSTRACT FROM AUTHOR]

Mesoporous Fe3O4-loaded silver nanocomposites (Fe3O4@Ag) were simply fabricated as bi-functional nanozymes for the catalysis-based detection and removal of Hg2+ ions. It was found that the as-prepared magnetic Fe3O4@Ag could display peroxidase-like catalysis activity that could be rationally enhanced in the presence of Hg2+ ions. To our surprise, the shell of the Ag element may decrease the catalysis of the Fe3O4 to some degree. However, the Ag particles could serve as the probes for specifically recognizing Hg2+ ions and trigger increased catalysis through the formation of Ag–Hg alloys, with a decreased signal background. A high-throughput colorimetric analytical method was thereby developed based on the Fe3O4@Ag catalysis for probing Hg2+ ions in the muscles of fish by using 96-well plates, at linear Hg2+ concentrations ranging from 0.010 to 2.5 mg kg−1. Moreover, the developed colorimetric analytical method was applied to evaluate Hg2+ levels in muscle samples of different kinds of fish. Unexpectedly, an obvious difference of Hg2+ levels in muscles of four kinds of fish was discovered, with the order of snakehead (Ophicephalus argus) > largemouth bass (Micropterus salmoides) > crucian carp (Carassius auratus) > silver carp (Hypophthalmichthys molitrix), where the carnivorous fish showed higher Hg2+ levels than the omnivorous or plant-based ones. Moreover, the as-fabricated Fe3O4@Ag adsorbents with their large specific surface area and high environmental robustness could exhibit efficient Hg2+ adsorption with capacities of up to 397.60 mg g−1. A removal efficiency of 99.40% can also be expected for Hg2+ ions from wastewater, with the magnet-aided recycling of Fe3O4@Ag adsorbents. Such an Fe3O4@Ag-based colorimetric analysis and removal strategy for Hg2+ ions should find wide applications in the fields of aquatic food safety, environmental monitoring, and clinical diagnostics of Hg-poisoning diseases. [ABSTRACT FROM AUTHOR]

SUMMARY: Miraculin‐like proteins (MLPs), members of the Kunitz trypsin inhibitor (KTI) family that are present in various plants, have been discovered to have a role in defending plants against pathogens. In this study, we identified a gene StMLP1 in potato that belongs to the KTI family. We found that the expression of StMLP1 gradually increases during Ralstonia solanacearum (R. solanacearum) infection. We characterized the promoter of StMLP1 as an inducible promoter that can be triggered by R. solanacearum and as a tissue‐specific promoter with specificity for vascular bundle expression. Our findings demonstrate that StMLP1 exhibits trypsin inhibitor activity, and that its signal peptide is essential for proper localization and function. Overexpression of StMLP1 in potato can enhance the resistance to R. solanacearum. Inhibiting the expression of StMLP1 during infection accelerated the infection by R. solanacearum to a certain extent. In addition, the RNA‐seq results of the overexpression‐StMLP1 lines indicated that StMLP1 was involved in potato immunity. All these findings in our study reveal that StMLP1 functions as a positive regulator that is induced and specifically expressed in vascular bundles in response to R. solanacearum infection. Significance Statement: In this work, we reported StMLP1, a member of the Kunitz trypsin inhibitor (KTI) family, both induced and specificity expressed in the vascular bundles. Specifically, we show that StMLP1 had trypsin inhibitor activity, and the expressed StMLP1 contributes to potato bacterial wilt resistance. This study enhances our understanding of the function of StMLP1, which may aid researchers in developing solutions for plant diseases. [ABSTRACT FROM AUTHOR]

The current world business environment is characterized by increasing uncertainties, complexities, and risks, which require agri-food supply chain (AFSC) managers to respond and act quickly in a context full of instability and unpredictability. Increasing pressure placed on AFSC managers intensifies the need to combine knowledge management (KM) and decision support that rapidly overcome knowledge boundaries. It has been recognized that the research issue related to the knowledge mobilization crossing boundaries in the AFSC needs to be addressed. This paper investigates knowledge boundaries and boundary-spanning mechanisms by collecting data from experienced AFSC practitioners. Empirical results verify that knowledge boundaries such as syntactic boundaries, semantic boundaries, and pragmatic boundaries could be effectively tackled by four specific boundary-spanning mechanisms: boundary spanners, boundary objects, boundary practices, and boundary discourses. [ABSTRACT FROM AUTHOR]

Agri-food supply chains (AFSCs) are becoming more complex in structure, and thus more susceptible to different vulnerabilities and risks. Therefore, to enhance performance, we need to manage the risks in AFSCs effectively and efficiently. This study analyses various AFSC risks using a multi-method approach, including thematic analysis, total interpretive structural modelling (TISM) and fuzzy cross-impact matrix multiplication applied to classification (MICMAC) analysis. Based on the empirical data collected from experienced AFSC practitioners and following thematic analysis, eight categories of risk and 16 risk factors were identified as important. Furthermore, the interrelationships among the identified risks were built using TISM. Finally, the identified risks were classified into various categories according to their dependence and driving power using fuzzy MICMAC analysis. The research results indicate that the weather-related and political risks have the highest driving power and are located at the lowest level in the TISM hierarchy. These risks have a high tendency to disturb the whole flow of AFSC and so should be managed effectively. This study advances existing literature on identifying risk factors, defining interrelations between different AFSC risks, and determining the key risks. The risk analysis results can help AFSC practitioners in AFSC to identify, categorise and analyse the risks. [ABSTRACT FROM AUTHOR]

This study was undertaken to investigate whether chitosan treatments of sprouts of three soybean [Glycine max (L.) Merr.] cultivars (OAC Champion, AC Orford, and AC Proteina) can increase not only concentration of isoflavones in sprouts but also the transcript levels of genes and their subfamilies encoding enzymes at key points of the phenylpropanoid pathway (phenylalanine ammonia-lyase [E.C. 4.3.1.5], chalcone synthase [E.C. 2.3.1.74], chalcone isomerase [E.C. 5.5.1.6], and chalcone reductase [E.C. 2.3.1.170]), and at a key branch-point enzyme in isoflavone biosynthesis (isoflavone synthase [E.C. 1.14.13.86]). Chitosan effects on transcript levels of 14 genes differed depending on the cultivar as demonstrated by significant interactions (P < 0.05) between soybean cultivar and chitosan treatment for all genes. For all cultivars, response to chitosan treatments varied significantly depending on the gene. Overall, the greatest response was observed with high molecular weight chitosan. Very-low- and low-isoflavone cultivars (i.e., AC Orford and OAC Champion) sometimes responded positively to chitosan treatments, while the high-isoflavone cultivar (i.e., AC Proteina) responded only negatively to chitosan. Chitosan treatments had limited effect on isoflavone concentrations, only reducing glycitein in OAC Champion by 38%. No correlation was found between gene expression and isoflavone concentrations. Differences in isoflavone concentrations were observed between sprouts of the three cultivars; AC Proteina had the highest isoflavone concentration and AC Orford the lowest. Results indicate that although isoflavone concentration and gene expression varied with cultivar, chitosan treatment is not a viable option for increasing isoflavone content in sprouts of cultivars evaluated.