Systemic acquired resistance (SAR) has long been viewed as a salicylate-driven process. Recent evidence by Gaikwad et al. reveals an earlier, jasmonate- and calcium (Ca2+)-dependent systemic phase that precedes salicylate accumulation. This temporal dynamic refines prevailing models of jasmonate-salicylate crosstalk and suggests a previously underappreciated early phase of SAR establishment.

Plants rely on pattern recognition receptors (PRRs) to detect pathogens, yet PRRs differ across species. Ngou et al. show that convergent evolution yields a shared recognition logic in the selective cold shock protein receptor (SCORE) for bacterial cold shock protein peptides. Structure-guided design yields synthetic SCORE variants that broaden detection, offering robust, broad-spectrum crop resistance.

Covalent modifications of RNA modulate plant growth, development, and stress responses. N4-acetylcytidine (ac4C), a conserved RNA modification deposited by N-ACETYLTRANSFERASES FOR CYTIDINE IN RNA (ACYRs), regulates RNA stability and translation, but its possible function in plant responses to cadmium (Cd) has not been explored. We report here that ACYR-mediated RNA ac4C modification negatively affects Cd tolerance during the vegetative growth of Arabidopsis (Arabidopsis thaliana). Cd treatment repressed the expression of ACYR1 and ACYR2, as well as the abundance of their encoded proteins, leading to lower overall ac4C-modified mRNA levels. Multiomics data combined with biochemical assays revealed that ACYR-dependent ac4C modification of the IRON MAN 2 (IMA2) and IMA3 transcripts enhanced their stability and translation. Lower levels of mRNA ac4C modification, induced by Cd treatment or by the loss of ACYR function, resulted in decreased abundance of IMA2 and IMA3 transcripts and their encoded peptides, leading to the ubiquitination and accelerated degradation of the basic helix-loop-helix (bHLH) transcription factors bHLH105 and bHLH115. This, in turn, suppressed the expression of bHLH Ib subfamily genes (bHLH38, bHLH39, bHLH100, and bHLH101) and of IRON-REGULATED TRANSPORTER 1, thereby preventing Cd uptake. Notably, IMA2 overexpression effectively restores the Cd-sensitive phenotype of the acyr mutant. Our findings reveal a mechanism by which ACYR-mediated ac4C modification regulates Cd uptake in Arabidopsis, providing potential targets for breeding crops with increased tolerance to Cd.

The BARELY ANY MERISTEM 1-AVRPPHB SUSCEPTIBLE 1 (PBS1) module is an early plasma membrane switch activating reactive oxygen species-dependent heat responses. PBS1 may integrate heat and immunity, offering targets for breeding climate-resilient crops.

Salicylic acid (SA) is essential for plant immunity, but excessive SA accumulation accelerates leaf senescence, necessitating tight control of its biosynthesis. Although AVRPPHB SUSCEPTIBLE3 (PBS3) is a key enzyme in SA biosynthesis, how PBS3 abundance is regulated to coordinate immunity and longevity remains unclear. Using genetic, biochemical, and physiological analyses, we show that PBS3 functions as a quantitative regulator of the immunity-longevity balance. Loss of PBS3 compromises disease resistance but delays senescence, whereas graded increases in PBS3 abundance progressively enhance pathogen-induced SA accumulation, systemic acquired resistance (SAR), and senescence severity. We further identify the E3 ubiquitin ligase PLANT U-BOX PROTEIN 13 (PUB13) as a direct regulator of PBS3. PUB13 physically associates with PBS3 and promotes its polyubiquitination and degradation through the 26S proteasome pathway. Disruption of PUB13 stabilizes PBS3, resulting in elevated SA accumulation, enhanced SAR, and accelerated leaf senescence. Time-course analyses revealed that pathogen-induced PBS3 accumulation and SA biosynthesis are transient in wild-type plants but remain elevated in pub13 mutants, indicating that PUB13 promotes the attenuation of immune-associated SA production after defense activation. Together, our findings establish the PUB13-PBS3 module as a post-translational mechanism that fine-tunes SA biosynthesis, enabling effective immunity while preventing prolonged SA accumulation and its detrimental effects on plant longevity.

This commentary explores recent advances that reveal how auxin transport and signaling precisely regulate its function in plant growth and development and offer new tools for precise plant engineering. These advances include a high-resolution structures of AUX1 and insights into TIR1-generated cyclic AMP signaling and the bi-layer ARF/cis-element code.

Cys-oxidation is a well-established post-translational regulator of intracellular protein function, yet its role in extracellular receptor-mediated signaling remains poorly understood. Here, we investigate the LRR-Malectin receptor-like kinase IGP1, a key receptor for plant cell wall damage-associated molecular patterns (DAMPs). We demonstrate that IGP1 directly recognizes cellooligomers with a degree of polymerization ≥ 3 via a conserved binding groove in its LRR domain, not the malectin domain as anticipated. Strikingly, a pair of cysteines within the malectin domain functions as a redox sensor, undergoing hydrogen peroxide-induced oxidation that sterically reduces ligand binding affinity and attenuates immune signaling. Phylogenetic analyses reveal that IGP originated after the terrestrialization of plants, and is an evolutionarily conserved redox sensor in land plants. Functional studies in Arabidopsis ( Arabidopsis thaliana ), wheat ( Triticum aestivum ), and soybean ( Glycine max ) confirm that the IGP-cellooligomer module confers broad-spectrum disease resistance. Our work uncovers a unique mechanism where ligand perception and redox sensing are integrated into a single receptor to regulate DAMP-triggered immunity. ### Competing Interest Statement The authors have declared no competing interest. National Natural Science Foundation of China, 32572840, 32572775 Excellent Research Group Project of the National Natural Science Foundation of China, 32488102 Hundred Talents Program of the Chinese Academy of Science Young Elite Scientists Sponsorship Program by the China Association for Science and Technology Project of State Key Laboratory of Plant Diversity and Specialty Crops, PDSC2024-6 Excellent Youth Foundation of Jiangsu Province, BK20250197 Excellent Youth Foundation of Henan Scientific Committee, 111/30603048 Young Elite Scientists Sponsorship Program by Henan Association for Science and Technology, 2024HYTP012

Plants and animals face the shared challenge of immune homeostasis. Tomato anti-systemin (antiSYS) and human interleukin-1 receptor antagonist (IL-1Ra) exemplify convergent strategies to restrain phytocytokine/cytokine signaling. Understanding this shared logic offers opportunities to fine-tune plant immunity, minimize growth trade-offs, and enhance crop resilience.

Salicylic acid (SA) is a key defense hormone shaped by temperature. High temperatures suppress, while low temperatures enhance, SA biosynthesis and signaling, thereby influencing plant immunity and temperature resilience. This review synthesizes current understanding of how temperature modulates SA pathways and their cross-talk with other hormones to balance growth and defense. We also propose a conceptual model positioning SA as a central integrator of temperature perception, immune regulation, and hormonal signaling. However, key questions remain: How do plants sense temperature shifts to regulate SA dynamics? How do temperature-induced epigenetic changes in SA pathways contribute to long-term adaptation? And how can these insights inform crop improvement? Addressing these gaps is essential for developing climate-resilient crops.

Wheat faces escalating fungal threats. Tandem kinase protein-nucleotide-binding domain leucine-rich repeat (TKP-NLR) pairs function as ‘sensor-helper’ immune modules, combining effector recognition and signal transduction. Complementing classical NLR models, this discovery expands the framework for understanding immune receptor diversity and offers new strategies for engineering durable, broad-spectrum resistance.

Calcium ion (Ca2+) serves as a versatile and conserved second messenger in orchestrating immune responses. In plants, plasma membrane-localized Ca2+-permeable channels can be activated to induce Ca2+ influx from extracellular space to cytosol upon pathogen infection. Notably, different immune elicitors can induce dynamic Ca2+ signatures in the cytosol. During pattern-triggered immunity, there is a rapid and transient increase in cytosolic Ca2+, whereas in effector-triggered immunity, the elevation of cytosolic Ca(2+ )is strong and sustained. Numerous Ca2+ sensors are localized in the cytosol or different intracellular organelles, which are responsible for detecting and converting Ca2+ signals. In fact, Ca2+ signaling coordinated by cytosol and subcellular compartments plays a crucial role in activating plant immune responses. However, the complete Ca2+ signaling network in plant cells is still largely ambiguous. This review offers a comprehensive insight into the collaborative role of intracellularCa(2+) stores in shaping the Ca2+ signaling network during plant immunity, and several intriguing questions for future research are highlighted.

Calcium ions (Ca2+) serve as key messengers in plant immune reactions. A typical Ca2+ signaling involves three steps: encoding specific Ca2+ signatures by Ca2+-permeable channels, decoding Ca2+ signals by Ca2+ sensors, and downstream responses. This review focuses on plasma membrane-localized Ca2+-permeable channels and cytosolic Ca2+ sensors, unraveling their roles in cytosolic Ca2+ influx and immune signaling during pattern-triggered immunity, effector-triggered immunity, and autoimmunity. Several unresolved questions were highlighted, including the regulation of Ca2+-permeable channel activity for immune induction and the mechanism behind Ca2+ influx-triggered hypersensitive response cell death. This concise overview provides insights into the complex interplay of Ca2+ signaling in plant immunity, paving the way for future investigations on molecular plant-microbe interactions.

AVRPPHB SUSCEPTIBLE 3 (PBS3) belongs to the GH3 family of acyl acid amido synthetases, which conjugates amino acids to diverse acyl acid substrates. Recent studies demonstrate that PBS3 in Arabidopsis plays a key role in the biosynthesis of plant defense hormone salicylic acid (SA) by catalyzing the conjugation of glutamate to isochorismate to form isochorismate-9-glutamate, which is then used to produce SA through spontaneous decay or ENHANCED PSEUDOMONAS SUSCEPTIBILITY (EPS1) catalysis. Consistent with its function as an essential enzyme for SA biosynthesis, PBS3 is well known to be a positive regulator of plant immunity in Arabidopsis. Additionally, PBS3 is also involved in the trade-off between abiotic and biotic stress responses in Arabidopsis by suppressing the inhibitory effect of abscisic acid on SA-mediated plant immunity. Besides stress responses, PBS3 also plays a role in plant development. Under long-day conditions, PBS3 influences Arabidopsis flowering time by regulating the expression of flowering regulators FLOWERING LOCUS C and FLOWERING LOCUS T. Taken together, PBS3 functions in the signaling network of plant development and responses to biotic and/or abiotic stresses, but the molecular mechanisms underlying its diverse roles remain obscure.

Plants rely on PAMP-triggered immunity (PTI) and effector-triggered immunity (ETI) to detect invading pathogens and subsequently activate defense mechanisms. Recently, four Nature papers (Yuan et al., Ngou et al., Pruitt et al., and Tian et al.) demonstrated that important components in PTI and ETI are required for both PTI and ETI, and PTI and ETI potentiate each other to achieve stronger plant defenses.

Aims The study aims to identify a novel plant growth-promoting bacteria (PGPB), which contributes to promoting growth and reducing cadmium (Cd) concentration in rice under Cd-contaminated conditions. Methods and Results Nine bacterial strains were isolated from plants grown in Cd-contaminated soil. These bacteria were tolerant to 1000 mu mol/L CdCl2, capable of producing indole-3-acetic acid, fixing nitrogen and solubilizing phosphate. The result of hydroponic experiment showed that under the control and Cd stress conditions, the dry weight of the Tm02-inoculated rice seedlings increased significantly. Furthermore, under Cd stress, the concentration of Cd in the shoot of the Tm02-inoculated seedlings decreased significantly, while there was no significant difference in Cd concentration between treatment with other eight strains and noninoculated seedlings. The same results were observed in the pot experiment as well, where there was a significantly reduced Cd concentration in rice grains of the Tm02-inoculated rice plants. Tm02 was classified as Pantoea agglomerans through 16S rDNA sequencing. Conclusions A novel PGPB strain Tm02 was identified and confirmed that it has the function of promoting rice growth and reducing Cd concentration in rice grain under Cd-contaminated conditions. This strain has the potential to improve rice yield in Cd-contaminated paddy fields. Significance and Impact of the Study This study provides a new example of using PGPB to improve the tolerance of rice to Cd pollution.

Salicylic acid (SA) is a plant defense signal that mediates local and systemic immune responses against pathogen invasion. However, the underlying mechanism of SA-mediated defense is very complex due to the involvement of various positive and negative regulators to fine-tune its signaling in diverse pathosystems. Upon pathogen infections, elevated level of SA promotes massive transcriptional reprogramming in which Non-expresser of PR genes 1 (NPR1) acts as a central hub and transcriptional coactivator in defense responses. Recent findings show that Enhanced Disease Susceptibility 1 (EDS1) also functions as a transcriptional coactivator and stimulates the expression of PR1 in the presence of NPR1 and SA. Furthermore, EDS1 stabilizes NPR1 protein level, while NPR1 sustains EDS1 expression during pathogenic infection. The interaction of NPR1 and EDS1 coactivators initiates transcriptional reprogramming by recruiting cyclin-dependent kinase 8 in the Mediator complex to control immune responses. In this review, we highlight the recent breakthroughs that considerably advance our understanding on how transcriptional coactivators interact with their functional partners to trigger distinct pathways to facilitate immune responses, and how SA accumulation induces dynamic changes in NPR1 structure for transcriptional reprogramming. In addition, the functions of different Mediator subunits in SA-mediated plant immunity are also discussed in light of recent discoveries. Taken together, the available evidence suggests that transcriptional coactivators are essential and potent regulators of plant defense pathways and play crucial roles in coordinating plant immune responses during plant-pathogen interactions.

Arsenic (As) contamination in paddy soil reduces rice production and quality. It is important to increase the As tolerance of rice and reduce As accumulation in rice using exogenous methods. We examined the effects of exogenous plant hormones on the growth of and As accumulation in rice exposed to As. Under hydroponic conditions, 10 μmol L−1 As inhibited the growth of rice seedling. However, pretreatments with indole-3-acetic acid (IAA), salicylic acid (SA), and gibberellins (GA) rescued this inhibition, as evidenced by changes in plant morphology (root and shoot elongation, biomass, total root length, root surface area, root volume, and root tip number) and root activities, especially with the application of IAA. The As concentration in rice seedlings was significantly reduced. With soil culture, 20 mg L−1 IAA application significantly increased the grain biomass of both rice varieties, the 1000-grain weight and plant biomass of Mo Wang Gu Nei (MWGN), while decreased the As concentration in rice grains and total As accumulation in grains per plant. Furthermore, exogenous IAA reduced As translocation, as evidenced by lower As concentrations in upper leaves and internodes, but higher levels in lower leaves and internodes in Dong Ting Wan Xian (DTWX) after spraying with IAA compared to the control treatments. In conclusion, exogenous IAA can significantly promote rice growth and reduce As accumulation in rice grains.

生境适合度是包括气候、食物和风险等诸多环境因素的综合性概念,对高原鼠兔(Ochotona curzoniae)的自然分布格局及种群动态具有决定性影响.本研究以高原鼠兔对栖息环境基本表征的选择偏好为依据,通过对不同植被斑块间鼠群特征的对比分析,对高原鼠兔栖息地适合度与降雪的关系进行了研究.结果表明:雪被消融速率与鼠群密度、裸地面积和土丘数量间呈显著正相关关系(P<0.05),与植被高度则呈显著负相关关系;降雪后鼠兔能否在最短时间内获得食物是高原鼠兔栖息地适合度的重要指征,也是高原鼠兔行为导向的基本动因.植被性状是影响雪被消融速率的重要因素,其斑块状的分异特征是决定高原鼠兔种群分布格局以及预测其动态趋势的重要指征.