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Salicylic acid (SA) is an aromatic plant hormone mediating plant growth, development, and immunity, including local and systemic defenses against pathogens and pests. Research for the past three decades has advanced our understanding of the SA pathway, from metabolic enzymes and receptors to signaling components and gene regulation. Key components of SA biosynthesis, signaling, metabolism, and transport are impacted by changing abiotic (e.g., temperature, water availability) and biotic factors (e.g., commensal and beneficial microbes). Temperature regulation of the SA pathway has led to the discovery of major thermosensitive nodes at various levels of gene/protein regulation. Microbiome modulation of the SA pathway at the single species and community levels are being disentangled, revealing mechanisms that rely on canonical plant hormone crosstalk. Salicylic acid (SA) is a central plant hormone mediating immunity, growth, and development. Recently, studies have highlighted the sensitivity of the SA pathway to changing climatic factors and the plant microbiome. Here we summarize organizing principles and themes in the regulation of SA biosynthesis, signaling, and metabolism by changing abiotic/biotic environments, focusing on molecular nodes governing SA pathway vulnerability or resilience. We especially highlight advances in the thermosensitive mechanisms underpinning SA-mediated immunity, including differential regulation of key transcription factors (e.g., CAMTAs, CBP60g, SARD1, bHLH059), selective protein–protein interactions of the SA receptor NPR1, and dynamic phase separation of the recently identified GBPL3 biomolecular condensates. Together, these nodes form a biochemical paradigm for how the external environment impinges on the SA pathway. [ABSTRACT FROM AUTHOR]

• Climate change has a significant impact on the plant immune system. • Pan-genomes of crop species likely hold important alleles for climate and disease resilience. • CRISPR-Cas technology may revolutionize crop engineering for climate and disease resilience. A grand challenge facing plant scientists today is to find innovative solutions to increase global crop production in the context of an increasingly warming climate. A major roadblock to global food sufficiency is persistent loss of crops to plant diseases and insect infestations. The United Nations has declared 2020 as the International Year of Plant Health. For historical reasons, molecular studies of plant-biotic interactions in the past several decades have not paid enough attention to how variable climate conditions affect plant-biotic interactions. Here, we highlight a few recent studies that begin to reveal how major climatic drivers impact the plant immune system, particularly secondary messenger and defense hormone signaling, and discuss possible approaches toward engineering climate-resilient plant immunity as part of an ongoing global effort to design 'dream' crops of the future. [ABSTRACT FROM AUTHOR]

Abstract AtUBC32, AtUBC33, and AtUBC34 comprise Arabidopsis group XIV E2 ubiquitin-conjugating enzymes. Yeast two-hybrid, in vitro pull-down, and bimolecular fluorescence complementation assays revealed that group XIV E2s are interacting partners of the U-box-type E3 ligase PUB19, a negative regulator of drought stress response. These three AtUBCs are co-localized with PUB19 to the punctae-like structures, most of which reside on the endoplasmic reticulum membrane of tobacco leaf cells. Suppression of AtUBC32 , AtUBC33 , and AtUBC34 resulted in increased abscisic acid-mediated stomatal closure and tolerance to drought stress. These results indicate that Arabidopsis group XIV E2s play negative roles in drought stress response. [ABSTRACT FROM AUTHOR]