Plant Immunity Research Articles

Identification of new salicylic acid signaling regulators for root development and microbiota composition in plants.

Besides playing a crucial role in plant immunity via the nonexpressor of pathogenesis-related (NPR) proteins, increasing evidence shows that salicylic acid (SA) can also regulate plant root growth. However, the transcriptional regulatory network controlling this SA response in plant roots is still unclear. Here, we found that NPR1 and WRKY45, the central regulators of SA response in rice leaves, control only a reduced sector of the root SA signaling network. We demonstrated that SA attenuates root growth via a novel NPR1/WRKY45-independent pathway. Furthermore, using regulatory network analysis and mutant characterization, we identified a set of new NPR1/WRKY45-independent regulators that conservedly modulate the root development and root-associated microbiota composition in both Oryza sativa (monocot) and Arabidopsis thaliana (dicot) in response to SA. Our results established the SA signaling as a central element regulating plant root functions under ecologically relevant conditions. These results provide new insights to understand how regulatory networks control plant responses to abiotic and biotic stresses.

Transcriptomic Study of Nicotiana tabacum Treated with the Bacterial Protein CspD Reveals Some Specific Abiotic Stress Responses

The ability of a cold-shock protein CspD from Bacillus thuringiensis to protect both dicots and monocots against various pathogens is well confirmed under both greenhouse and field conditions; however, the molecular basis of this phenomenon at the transcriptomic level still remains unexplored. Expression profiles of some marker genes associated with SAR/ISR nonspecific resistance pathways and ROS scavengers were examined in CspD-treated Nicotiana tabacum plants, and the RNA-seq analysis of CspD-treated plants was first carried out. The ISR markers PDF1.2 and PR4 were overexpressed locally in treated tobacco leaves with the maximum 2.4- and 5.7-fold change, respectively, reached 12 h after the leaf treatment with CspD; PDF1.2 was also up-regulated 4.8-fold four days after the inoculation of treated plants with TMV. The ROS scavenger analysis demonstrated overexpression of Cu-Zn superoxide dismutase in both treated (with the maximum 5.4-fold change observed 6 h after the treatment) leaves and leaves from the upper tier (“system” leaves, 6.5-fold change observed 4 days after the treatment). The ROS assay confirmed endogenous accumulation of superoxide in CspD-treated leaves 6 and 24 h after the treatment. An in silico comparative study of Arabidopsis orthologs of highly up-regulated tobacco genes induced by CspD with Arabidopsis genes activated by some other molecular patterns revealed the specific CspD-induced expression of Cu-Zn superoxide dismutase and some other genes associated with light and cold responses. This study may contribute to a better understanding of cross-talking between abiotic stress and nonspecific immunity in plants.

The E3 ubiquitin ligase TaGW2 facilitates TaSnRK1γ and TaVPS24 degradation to enhance stripe rust susceptibility in wheat.

Wheat stripe rust, caused by the fungal pathogen Puccinia striiformis f. sp. tritici (Pst), threatens global wheat production, and therefore discovering genes involved in stripe rust susceptibility is essential for balancing yield with disease resistance in sustainable breeding strategies. Although TaGW2 is well known to negatively regulate wheat kernel size and weight, its role in stress response remains unclear. Here, we found that TaGW2 transcription levels increased following inoculation with Pst or treatment with flg22 or chitin. TaGW2 knockdown lines showed enhanced resistance to multiple Pst races, while TaGW2 overexpression reduced host defence response, promoted Pst growth and development and increased wheat susceptibility to Pst. Additionally, TaGW2 could mediate the ubiquitination and degradation of both TaSnRK1γ and TaVPS24 via the 26S proteasome pathway. Silencing TaSnRK1γ or TaVPS24 in wheat increased sensitivity to Pst, whereas overexpressing either gene enhanced wheat defence response, indicating that TaSnRK1γ and TaVPS24 act as positive regulators of Pst resistance. This study reveals a previously unrecognized mechanism inhibiting plant immunity to Pst through TaGW2-mediated ubiquitination and degradation of TaSnRK1γ and TaVPS24. This work also provides crucial genetic resources for breeding high-yield, stripe rust-resistant wheat varieties.

Protein Dynamics in Plant Immunity: Insights into Plant–Pest Interactions

All living organisms regulate biological activities by proteins. When plants encounter pest invasions, the delicate balance between protein synthesis and degradation becomes even more pivotal for mounting an effective defense response. In this review, we summarize the mechanisms by which plants regulate their proteins to effectively coordinate immune responses during plant–pest interactions. Additionally, we discuss the main pathway proteins through which pest effectors manipulate host protein homeostasis in plants to facilitate their infestation. Understanding these processes at the molecular level not only deepens our knowledge of plant immunity but also holds the potential to inform strategies for developing pest-resistant crops, contributing to sustainable and resilient agriculture.

VOZ‐dependent priming of salicylic acid‐dependent defense against Rhizopus stolonifer by β‐aminobutyric acid requires the TCP protein TCP2 in peach fruit

SUMMARYVascular plant one‐zinc finger (VOZ) transcription factors (TFs) play crucial roles in plant immunity. Nevertheless, how VOZs modulate defense signaling in response to elicitor‐induced resistance is not fully understood. Here, the defense elicitor β‐aminobutyric acid (BABA) resulted in the visible suppression of Rhizopus rot disease of peach fruit caused by Rhizopus stolonifer. Defense priming by BABA was notably associated with increased levels of salicylic acid (SA) and SA‐dependent gene expression. Data‐independent acquisition proteomic analysis revealed that two VOZ proteins (PpVOZ1 and PpVOZ2) were substantially upregulated in BABA‐induced resistance (BABA‐IR). Furthermore, the interaction of PpVOZ1 and PpVOZ2 and their potential target of the TEOSINTE‐BRANCHED1/CYCLOIDEA/PCF (TCP)‐family protein PpTCP2 screened from protein–protein interaction networks was confirmed by yeast two‐hybrid (Y2H), luciferase complementation imaging and glutathione S‐transferase pull‐down assays. Furthermore, subcellular localization, yeast one‐hybrid, electrophoretic mobility shift assay and dual‐luciferase reporter assays demonstrated that nuclear localization of both PpVOZ1 and PpVOZ2 was critical for their contribution to BABA‐IR, as these proteins potentiated the PpTCP2‐mediated transcriptional activation of isochorismate synthase genes (ICS1/2). The overexpression of both PpVOZ1 and PpVOZ2 could activate the transcription of SA‐dependent genes and provide disease resistance in transgenic Arabidopsis. In contrast, the ppvoz1cas9 and ppvoz2cas9 loss‐of‐function mutations and the voz1cas9 voz2cas9 double mutation attenuated BABA‐IR against R. stolonifer. Therefore, the three identified positive TFs, PpVOZ1, PpVOZ2, and PpTCP2, synergistically contribute to the BABA‐activated priming of systemic acquired resistance in postharvest peach fruit by a VOZ‐TCP‐ICS regulatory module.

Chalcone derivatives containing 1,2,4-triazole and pyridine moiety: design, synthesis, and antiviral activity.

A series of chalcone derivatives containing 1,2,4-triazole and pyridine were designed and synthesized, and their antiviral activities against tobacco mosaic virus (TMV) were evaluated. Notably, S7 (EC50 = 89.7μg/mL) exhibited excellent curative activity against the TMV, which was superior to that of ningnanmycin (NNM: EC50 = 201.7μg/mL). Molecular docking showed that S7 exhibited satisfactory affinities for the TMV coat protein (TMV-CP), with four strong conventional hydrogen bonds with amino acid residues. Further, microscale thermophoresis (MST) showed that S7 (Kd = 0.5340 ± 0.2233 μmol/L) bound more strongly to TMV-CP than NNM (Kd = 5.1186 ± 1.9568μmol/L). The results of chlorophyll content, malondialdehyde (MDA) content, and biological enzyme activity confirmed that S7 enhanced the disease resistance of tobacco plants by affecting the change of chlorophyll content, interfering with plant lipid peroxidation, and enhancing SOD activity in plants, respectively.

An enhancer-promoter-transcription factor module orchestrates plant immune homeostasis by constraining camalexin biosynthesis

Effective plant defense against pathogens relies on highly coordinated regulation of immune gene expression. Enhancers, as cis-regulatory elements, are indispensable determinants of dynamic gene regulation, but the molecular functions in plant immunity are not well understood. In this study, we identified a novel enhancer, CORE PATTERN-INDUCED ENHANCER 35 (CPIE35), which is rapidly activated upon pathogenic elicitation and negatively regulates anti-fungal resistance through modulating WRKY15 expression. During immune activation, CPIE35 activates the transcription of WRKY15 by forming chromatin loops with the promoter of WRKY15 in a WRKY18/40/60-, WRKY33-, and MYC2-dependent manner. WRKY15 directly binds to the promoters of PAD3 and GSTU4, suppressing their expression and leading to the reduced camalexin synthesis and resistance. Interestingly, CPIE35 region is evolutionarily conserved among Brassicaceae plants, and the CPIE35-WRKY15 module exerts similar functions in Brassica napus to negatively regulate anti-fungal resistance. Our work reveals the “enhancer-promoter-transcription factor” regulatory mechanism in maintenance of immune homeostasis, highlighting the importance and conserved role of enhancers in fine-tuning immune gene expression in plants.

Characterization of the chitinase gene family in Saccharum reveals the disease resistance mechanism of ScChiVII1.

A chitinase gene ScChiVII1 which is involved in defense against pathogen stress was characterized in sugarcane. Chitinases, a subclass of pathogenesis-related proteins, catalyze chitin hydrolysis and play a key role in plant defense against chitin-containing pathogens. However, there is little research on disease resistance analysis of chitinase genes in sugarcane, and the systematic identification of their gene families has not been reported. In this study, 85 SsChi and 23 ShChi genes, which were divided into 6 groups, were identified from the wild sugarcane species Saccharum spontaneum and Saccharum hybrid cultivar R570, respectively. Transcriptome analysis and real-time quantitative PCR revealed that SsChi genes responded to smut pathogen stress. The chitinase crude extracted from the leaves of transgenic Nicotiana benthamiana plants overexpressing ScChiVII1 (a homologous gene of SsChi22a) inhibited the hyphal growth of Fusarium solani var. coeruleum and Sporisorium scitamineum. Notably, the chitinase and catalase activities and the jasmonic acid content in the leaves of ScChiVII1 transgenic N. benthamiana increased after inoculation with F solani var. coeruleum, but the salicylic acid, hydrogen peroxide, and malondialdehyde contents decreased. Comprehensive RNA sequencing of leaves before (0day) and after inoculation (2days) revealed that ScChiVII1 transgenic tobacco enhanced plant disease resistance by activating transcription factors and disease resistance-related signaling pathways, and modulating the expression of genes involved in the hypersensitive response and ethylene synthesis pathways. Taken together, this study provides comprehensive information on the chitinase gene family and offers potential genetic resources for disease resistance breeding in sugarcane.

Induction of antiherbivore defense responses in poplars using a methyl jasmonate and mesoporous silica nanoparticle complex.

Poplar in China has long been plagued by the fall webworm Hyphantria cunea. Enhancing plant immunity using chemical elicitors is an environmentally friendly approach to pest control. The phytohormone methyl jasmonate (MeJA) can stimulate the chemical defenses of poplars against herbivores but has been shown to have limited efficacy in practice. Here, we studied the effects of a MeJA and mesoporous silica nanoparticle (MSN) complex (MeJA@MSN) regarding the induction of poplar resistance to H. cunea, which may provide strategies for the effective use of MeJA. The silicon-based phytohormone complex (MeJA@MSNs) exhibited excellent biological and physiochemical properties, such as excellent biocompatibility and plant tissue transportability. The changes in metabolites in poplar leaves induced by MeJA, MSNs, and MeJA@MSNs were investigated by metabolic analysis. MeJA@MSNs led to highly potent induced resistance along with elevated salicylaldehyde content, which increased with the dose administered. The salicylaldehyde metabolite showed a strong antifeedant effect on H. cunea larvae at a dosage of 1 μg, with the 50% lethal dose being 20.4 μg/mg. Furthermore, transcriptional analysis showed that MeJA@MSNs upregulated key genes in biosynthetic pathways more than MeJA and MSNs. Our results show that MeJA and MSNs interact positively in poplar, leading to salicylaldehyde accumulation and increased induced resistance to H. cunea, providing new insights into the underlying resistance mechanisms induced by MeJA@MSNs. © 2024 Society of Chemical Industry.

Proteolysis of host DEAD-box RNA helicase by potyviral proteases activates plant immunity.

The precise mechanisms by which plant viral proteases interact with and cleave host proteins, thereby participating in virus-host interactions, are not well understood. Potyviruses, the largest group of known plant-infecting RNA viruses, are known to rely on the nuclear inclusion protease a (NIa-Pro) for the processing of viral polyproteins. Here, we demonstrate that the proteolytic activity of NIa-Pro from potyvirus turnip mosaic virus (TuMV) is indispensable for inducing hypersensitive cell death in Nicotiana benthamiana. NIa-Pro targets and degrades the host DEAD-box protein 5 (DBP5) via a specific cleavage motif, which initiates host cell death. Both the silencing of DBP5 and the overexpression of NIa-Pro lead to an increased frequency of stop codon readthrough, which could be potentially harmful to the host, as it may result in the production of aberrant proteins. Unlike the NIa-Pro of most other potyviruses, the NIa-Pro of tobacco etch virus can also degrade DBP5 and trigger cell death, in both pepper and N. benthamiana. Furthermore, we discovered that the TuMV-encoded nuclear inclusion b can counteract NIa-Pro-induced cell death by co-opting DBP5. These findings unveil hitherto uncharacterized roles for plant virus proteases in cleaving host proteins and highlight the role of host DBP5 in modulating plant immunity.

Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity.

Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity.

LncRNA81246 regulates resistance against tea leaf spot by interrupting the miR164d-mediated degradation of NAC1.

Non-coding RNAs play crucial roles in plant responses to viral stresses. However, their molecular mechanisms in tea leaf spot responses remain unclear. In this study, using Camellia sinensis, we identified lncRNA81246 as a long non-coding RNA that localizes to both the nucleus and cytoplasm. It functions as a competitive endogenous RNA, thereby disrupting CsNAC1 (encoding NAC domain-containing protein 1) degradation mediated by miR164d. Silencing lncRNA81246 increased the resistance of tea plants to presistanceathogens, whereas transient lncRNA81246-overexpression plants showed decreased resistance to pathogens. Co-expression assays in Nicotiana benthamiana revealed that lncRNA81246 affects the miR164d-CsNAC1 regulatory module. Transient miR164d-overexpression and silencing assays demonstrated its positive regulation of tea plant resistance. Specifically, silencing its target, CsNAC1,enhanced disease resistance, whereas transient overexpression reduced plant resistance. Yeast one-hybrid, dual-luciferase, and RT-qPCR assay results suggested that CsNAC1 alters the expression of CsEXLB1, whereas AsODN and tobacco transient overexpression assays showed that CsEXLB1 negatively regulated tea plant resistance. Thus, our research demonstrated that lncRNA81246 acts as a mediator to interfere with the miR164d-CsNAC1 regulatory module involved in the disease resistance of tea plants.

A Stinkbug Salivary Protein Is Indispensable for Insect Feeding and Activates Plant Immunity.

Salivary proteins secreted by phytophagous insects play pivotal roles in plant-insect interactions. A salivary protein RpSP27, from the stinkbug Riptortus pedestris, a devastating pest on soybean, was selected for studying due to its ability to induce cell death and activate immune responses in plants. RpSP27 localized to the endoplasmic reticulum and triggered reactive oxygen species burst. Virus-induced gene silencing assays showed RAR1 plays an essential role in RpSP27-induced cell death in Nicotiana benthamiana. Expression analyses revealed that RpSP27 is predominantly expressed in R. pedestris salivary glands. RNA interference-mediated silencing of RpSP27 in R. pedestris significantly reduced insect survival rates and altered feeding behavior by decreasing the formation of salivary sheaths on soybeans and reducing probing and feeding duration. Furthermore, the silencing of RpSP27 in R. pedestris mitigated the staygreen syndrome in soybeans, characterized by delayed senescence and pod abnormalities. This study elucidated the role of RpSP27 in the interaction between R. pedestris and soybean, presenting a potential target for pest management strategies to protect soybean crops from the detrimental effects of R. pedestris feeding.

Genomes of two invasive Adelges species (hemlock woolly adelgid and pineapple gall adelgid) enable characterization of nicotinic acetylcholine receptors.

Two invasive hemipteran adelgids cause widespread damage to North American conifers. Adelges tsugae (the hemlock woolly adelgid) has decimated Tsuga canadensis and Tsuga caroliniana (the Eastern and Carolina hemlocks, respectively). A. tsugae was introduced from East Asia and reproduces parthenogenetically in North America, where it can kill trees rapidly. A. abietis, introduced from Europe, makes pineapple galls on several North American spruce species, and weakens trees, increasing their susceptibility to other stresses. Broad-spectrum insecticides that are often used to control adelgid populations can have off-target impacts on beneficial insects and the development of more selective chemical treatments could improve control methods and minimize ecological damage. Whole genome sequencing was performed on both species to aid in development of targeted pest control solutions and improve species conservation. The assembled A. tsugae and A. abietis genomes are 231.71 Mbp and 290.39 Mbp, respectively, each consisting of nine chromosomes and both genomes are over 96% complete based on BUSCO assessment. Genome annotation identified 11,424 and 14,118 protein-coding genes in A. tsugae and A. abietis, respectively. Comparative analysis across 29 Hemipteran species and 14 arthropod outgroups identified 31,666 putative gene families. Gene family expansions in A. abietis included ABC transporters and carboxypeptidases involved in carbohydrate metabolism, while both species showed contractions in core histone families and oxidoreductase pathways. Gene family expansions in A. tsugae highlighted families associated with the regulation of cell differentiation and development (survival motor protein, SMN; juvenile hormone acid methyltransferase JHAMT) as well as those that may be involved in the suppression of plant immunity (clip domain serine protease-D, CLIPD; Endoplasmic reticulum aminopeptidase 1, ERAP1). Among the analyzed gene families, Nicotinic acetylcholine receptors (nAChRs) maintained consistent copy numbers and structural features across species, a finding particularly relevant given their role as targets for current forestry management insecticides. Detailed phylogenetic analysis of nAChR subunits across adelgids and other ecologically important insects revealed remarkable conservation in both sequence composition and predicted structural features, providing crucial insights for the development of more selective pest control strategies.

Assessment of Aerial Blight Disease and Different Growth Parameter of Stevia Crop (Stevia rebaudiana) by Using Bioagents (Bacillus subtilis)

Stevia (Stevia rebaudiana Bertoni) has become a valuable crop due to its natural sweetness and wide-ranging applications in both the food and pharmaceutical industries. Despite its potential, stevia cultivation is hindered by diseases like aerial blight, caused by the fungal pathogen Rhizoctonia solani Kuhn, which leads to significant yield losses. This study explores the potential of Bacillus subtilis, a biological control agent, in mitigating the effects of this disease. Conducted during the kharif season of 2023-24, the experiment assessed various dosages (1- 4 l/ha) of the bioagent (Bacillus subtilis) and their effects on plant health, disease resistance, and overall yield. The results indicate that the application of Bacillus subtilis not only reduced the severity of aerial blight but also enhanced key growth parameters, including plant height and sucker production. During evaluation, all the seven treatments were found to be significantly superior over control in managing the disease. Among all the treatments the growth parameters were maximum in T5 ( Bacillus subtilis @ 3 l/ha) such as plant height (56.83 cm) number of suckers (55), fresh leaves yield (4.51) and dry leaves yield (4.00) and minimize the disease intensiy @ 12.23 % followed by T4 (Bacillus subtilis @ 2.5 l/ha), T6 ( Bacillus subtilis @ 3.5 l/ha) ,T7 (Bacillus subtilis @ 4 l/ha) ,T3 (Bacillus subtilis @ 2 l/ha) ,T2 (Bacillus subtilis @ 1.5 l/ha),T1 (Bacillus subtilis @ 1 l/ha) and T0 (untreated). Furthermore, an economic analysis confirmed the cost-effectiveness of this biological treatment, highlighting its potential as a sustainable alternative to chemical fungicides in stevia farming.

Rhizosphere Shifts: Reduced Fungal Diversity and Microbial Community Functionality Enhance Plant Adaptation in Continuous Cropping Systems

Continuous cropping problems constitute threats to perennial plant health and survival. Soil conditioners have the potential to enhance plant disease resistance in continuous cropping systems. However, how microbes and metabolites of the rhizosphere respond to soil conditioner addition remains largely unknown, but this knowledge is paramount to providing innovative strategies to enhance plant adaptation in continuous cropping systems. Here, we found that a biochar conditioner significantly improved plant survival rates in a continuous cropping system. The biochar-induced rhizosphere significantly alters the fungal community, causing a decline in fungal diversity and the downregulation of soil microbial community functionality. Specifically, the biochar-induced rhizosphere causes a reduction in the relative abundance of pathogenic Fusarium sp. and phenolic acid concentration, whose variations are the primary causes of continuous cropping problems. Conversely, we observed an unexpected bacterial diversity increase in rhizospheric and non-rhizospheric soils. Our research further identified key microbial taxa in the biochar-induced rhizosphere, namely, Monographella, Acremonium, Geosmithia, and Funneliformis, which enhance soil nutrient availability, suppress Fusarium sp., mitigate soil acidification, and reduce phenolic acid concentrations. Collectively, we highlight the critical role of regular microbial communities and metabolites in determining plant health during continuous cropping and propose a synthetic microbial community framework for further optimizing the ecological functions of the rhizosphere.

Prediction of Plant Resistance Proteins Using Alignment-Based and Alignment-Free Approaches.

Plant disease resistance (PDR) proteins are critical in identifying plant pathogens. Predicting PDR protein is essential for understanding plant-pathogen interactions and developing strategies for crop protection. This study proposes a hybrid model for predicting and designing PDR proteins against plant-invading pathogens. Initially, we tried alignment-based approaches, such as Basic Local Alignment Search Tool (BLAST) for similarity search and MERCI for motif search. These alignment-based approaches exhibit very poor coverage or sensitivity. To overcome these limitations, we developed alignment-free or machine learning (ML)-based methods using compositional features of proteins. Our ML-based model, developed using compositional features of proteins, achieved a maximum performance area under the receiver operating characteristic curve (AUROC) of 0.91. The performance of our model improved significantly from AUROC of 0.91-0.95 when we used evolutionary information instead of protein sequence. Finally, we developed a hybrid or ensemble model that combined our best ML model with BLAST and obtained the highest AUROC of 0.98 on the validation dataset. We trained and tested our models on a training dataset and evaluated them on a validation dataset. None of the proteins in our validation dataset are more than 40% similar to proteins in the training dataset. One of the objectives of this study is to facilitate the scientific community working in plant biology. Thus, we developed an online platform for predicting and designing plant resistance proteins, "PlantDRPpred" (https://webs.iiitd.edu.in/raghava/plantdrppred).

A C2H2-type zinc finger protein TaZFP8-5B negatively regulates disease resistance

BackgroundZinc finger proteins (ZFPs) are important regulators in abiotic and biotic stress tolerance in plants. However, the role of the ZFPs in wheat responding to pathogen infection is poorly understood.ResultsIn this study, we found TaZFP8-5B was down-regulated by Puccinia striiformis f. sp. tritici (Pst) infection. TaZFP8-5B possesses a single C2H2-type zinc finger domain with a plant-specific QALGGH motif, and an EAR motif (LxLxL) at the C-terminus. The EAR motif represses the trans-activation ability of TaZFP8-5B. Knocking down the expression of TaZFP8 by virus-induced gene silencing increased wheat resistance to Pst, whereas TaZFP8-5B-overexpressing reduced wheat resistance to stripe rust and rice resistance to Magnaporthe oryzae, suggesting that TaZFP8-5B plays a negative role in the modulation of plant immunity. Using bimolecular fluorescence complementation, split-luciferase, and yeast two-hybrid assays, we showed that TaZFP8-5B interacted with a wheat calmodulin-like protein TaCML21. Knock-down of TaCML21 reduced wheat resistance to Pst.ConclusionsThis study characterized the function of TaZFP8-5B and its interacting protein TaCML21. Our findings provide a new perspective on a regulatory module made up of TaCML21-TaZFP8-5B in plant immunity.

Expression analysis of defense signaling marker genes in Capsicum annuum in response to phytohormones elicitation.

To tolerate biotic stress, plants employ phytohormones such as jasmonic acid (JA), salicylic acid (SA), and ethylene (ET) to regulate the immune response against different pathogens. Phytohormone-responsive genes, known as "Defense signaling marker genes," are used to evaluate plant disease resistance during pathogen infection. Most information on these marker genes derives from studies on the model plant Arabidopsis thaliana. The present study was aimed analyze the effect of hormonal elicitation at different concentrations at 24h pos-treatment in the transcript level of 8 traditional genes selected for molecular studies plant-pathogen interactions in Capsicum. Chemical treatment was achieved by spraying leaves of in vitro seedlings C. annuum L. with 0.1mM, 1mM or 2.5mM ET; 1mM, 2.5mM, or 5mM SA; 2.5mM BABA; or 0.150mM MeJA. Twenty-four hours after treatments were applied molecular analyses were carried out using qPCR to investigate the expression. Results revealed that 1mM of ET or 0.15mM of MeJA activated the expression CaPR1 (18--11.64-fold change), CaLOX2 (13.80-fold), CaAP2/ERF06 (22- 5.3- fold change), and CaPDF1.2 (2.3-1.5- fold). While, 5mM of SA present effect of negative regulation on the expression in most of these genes. Our results show that the expression profile induced by phytohormones in CaPR1 are particular in C. annuum, because were significantly induced for ET/MeJA, and dow-regulation with SA Contrary to Arabidopsis. Although, on both plants it is observed the cross talk between JA/ET and SA mediated signal pathways for the regulation of this gene.

Machine learning-based identification of general transcriptional predictors for plant disease.

This study investigated the generalizability of Arabidopsis thaliana immune responses across diverse pathogens, including Botrytis cinerea, Sclerotinia sclerotiorum, and Pseudomonas syringae, using a data-driven, machine learning approach. Machine learning models were trained to predict disease development from early transcriptional responses. Feature selection techniques based on network science and topology were used to train models employing only a fraction of the transcriptome. Machine learning models trained on one pathosystem where then validated by predicting disease development in new pathosystems. The identified feature selection gene sets were enriched for pathways related to biotic, abiotic, and stress responses, though the specific genes involved differed between feature sets. This suggests common immune responses to diverse pathogens that operate via different gene sets. The study demonstrates that machine learning can uncover both established and novel components of the plant's immune response, offering insights into disease resistance mechanisms. These predictive models highlight the potential to advance our understanding of multigenic outcomes in plant immunity and can be further refined for applications in disease prediction.