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Salicylic acid (SA) is an important phytohormone, well‐known for its regulatory role in shaping plant immune responses. In recent years, significant progress has been made in unravelling the molecular mechanisms underlying SA biosynthesis, perception, and downstream signalling cascades. Through the concerted efforts employing genetic, biochemical, and omics approaches, our understanding of SA‐mediated defence responses has undergone remarkable expansion. In general, following SA biosynthesis through Avr effectors of the pathogens, newly synthesized SA undergoes various biochemical changes to achieve its active/inactive forms (e.g. methyl salicylate). The activated SA subsequently triggers signalling pathways associated with the perception of pathogen‐derived signals, expression of defence genes, and induction of systemic acquired resistance (SAR) to tailor the intricate regulatory networks that coordinate plant immune responses. Nonetheless, the mechanistic understanding of SA‐mediated plant immune regulation is currently limited because of its crosstalk with other signalling networks, which makes understanding this hormone signalling more challenging. This comprehensive review aims to provide an integrated overview of SA‐mediated plant immunity, deriving current knowledge from diverse research outcomes. Through the integration of case studies, experimental evidence, and emerging trends, this review offers insights into the regulatory mechanisms governing SA‐mediated immunity and signalling. Additionally, this review discusses the potential applications of SA‐mediated defence strategies in crop improvement, disease management, and sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Plants constantly perceive and process environmental signals and balance between the energetic demands of growth and defense. Growth arrest upon pathogen attack was previously suggested to result from a redirection of the plants' metabolic resources towards the activation of plant defense. The energy sensor Target of Rapamycin (TOR) kinase is a conserved master coordinator of growth and development in all eukaryotes. Although TOR is positioned at the interface between development and defense, little is known about the mechanisms by which TOR may potentially regulate the relationship between these two modalities. The plant hormones cytokinin (CK) and gibberellin (GA) execute various aspects of plant development and defense. The ratio between CK and GA was reported to determine the outcome of developmental programmes. Here, investigating the interplay between TOR‐mediated development and TOR‐mediated defense in tomato, we found that TOR silencing resulted in rescue of several different aberrant developmental phenotypes, demonstrating that TOR is required for the execution of developmental cues. In parallel, TOR inhibition enhanced immunity in genotypes with a low CK/GA ratio but not in genotypes with a high CK/GA ratio. TOR‐inhibition mediated disease resistance was found to depend on developmental status, and was abolished in strongly morphogenetic leaves, while being strongest in mature, differentiated leaves. CK repressed TOR activity, suggesting that CK‐mediated immunity may rely on TOR downregulation. At the same time, TOR activity was promoted by GA, and TOR silencing reduced GA sensitivity, indicating that GA signalling requires normal TOR activity. Our results demonstrate that TOR likely acts in concert with CK and GA signalling, executing signalling cues in both defense and development. Thus, differential regulation of TOR or TOR‐mediated processes could regulate the required outcome of development‐defense prioritisation. Summary Statement: Target of Rapamycin (TOR) is positioned at the interface between development and defense, but little is known about the mechanisms by which TOR may regulate shifts between them. Here, we demonstrate that TOR likely acts in concert with cytokinin and gibberellin to execute signalling cues in both defense and development. [ABSTRACT FROM AUTHOR]

SUMMARY: Bacterial fruit blotch, caused by Acidovorax citrulli, is a serious disease of melon and watermelon. The strains of the pathogen belong to two major genetic groups: group I strains are strongly associated with melon, while group II strains are more aggressive on watermelon. A. citrulli secretes many protein effectors to the host cell via the type III secretion system. Here we characterized AopW1, an effector that shares similarity to the actin cytoskeleton‐disrupting effector HopW1 of Pseudomonas syringae and with effectors from other plant‐pathogenic bacterial species. AopW1 has a highly variable region (HVR) within amino acid positions 147 to 192, showing 14 amino acid differences between group I and II variants. We show that group I AopW1 is more toxic to yeast and Nicotiana benthamiana cells than group II AopW1, having stronger actin filament disruption activity, and increased ability to induce cell death and reduce callose deposition. We further demonstrated the importance of some amino acid positions within the HVR for AopW1 cytotoxicity. Cellular analyses revealed that AopW1 also localizes to the endoplasmic reticulum, chloroplasts, and plant endosomes. We also show that overexpression of the endosome‐associated protein EHD1 attenuates AopW1‐induced cell death and increases defense responses. Finally, we show that sequence variation in AopW1 plays a significant role in the adaptation of group I and II strains to their preferred hosts, melon and watermelon, respectively. This study provides new insights into the HopW1 family of bacterial effectors and provides first evidence on the involvement of EHD1 in response to biotic stress. [ABSTRACT FROM AUTHOR]

Background: Menstruation is one of the most significant social, and psychological changes that a female experiences. A mixture of incomplete and erroneous information about the safe and hygienic menstrual practices, as well as improper menstrual management at home or school can be a significant barrier to girls' school attendance and educational experience quality. Menstrual hygiene being a multi-sectoral public health issue needs to be dealt in integration with education, health, women and child development and water sanitation hygiene (WASH). Objective: To assess the knowledge and practices towards menstruation and menstrual hygiene among adolescent girls and its association with the school environment. Method: This study was an analytical cross sectional study, conducted among the 850 adolescent girls of government and private schools in Haldwani. Data was analyzed using SPSS (version 16). Results: More than half of the participants from government and private school showed average knowledge and practices regarding menstruation and menstrual hygiene. Facilities in school related to menstrual hygiene management was found to be associated with menstrual hygiene practices among the study participants. (p<0.05) Conclusion: These findings indicate the need for education about safe and correct menstrual hygiene practices. School environment related to menstrual hygiene management should be improved and strengthened as per the need of adolescent population. [ABSTRACT FROM AUTHOR]