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Background: Flowering is a complex, finely regulated process involving multiple phytohormones and transcription factors. However, flowering regulation in pitaya (Hylocereus polyrhizus) remains largely unexamined. This study addresses this gap by investigating gibberellin-3 (GA3) effects on flower bud (FB) development in pitaya. Our findings reveal that GA3 application induces significant bud dormancy and suppresses FB formation, highlighting GA3's role in modulating flowering in this species. Results: GA3 application during peak flowering period significantly altered hormone levels, reducing auxin (AUX), cytokinin (CTK) active forms dihydrozeatin riboside (dhZR), zeatin riboside (ZR), N6-isopentenyladenosine (iPA), and brassinosteroid (BR), while increasing jasmonic acid (JA), GA3, and gibberellin-4 (GA4) levels, with abscisic acid (ABA) levels remaining unchanged compared to control. Conversely, FB formation was associated with increased levels of AUX, dhZR, ZR, iPA, ABA, and JA, and decreased GA3 and GA4 levels. Transcriptomic analysis revealed batches of differentially expressed genes (DEGs) associated with phytohormone signal transduction, aligning with observed hormone changes. Notably, except four CONSTANS-like (CO) (HU06G02633, HU10G00019, HU04G00234, and HU02G01458), all other CO genes were preferentially active in GA3-treated buds. GA3 treatment inhibited genes linked to the ABC model (AP1, AP2, MADS-box, AGL, SPL) and floral identity genes (LFY, FT), favoring dormancy and clean sweep of FB formation. Conclusion: These findings underscore the potential of GA3 as a powerful modulator of flowering and bud dormancy in pitaya. By elucidating the hormonal and genetic responses to GA3 treatment, this study contributes to our understanding of flowering regulation in pitaya and highlights the significant impact of GA3 on bud developmental pathways. [ABSTRACT FROM AUTHOR]

Linalool is anticipated to have significant ecological roles. In this study, linalyl 6- O -α-arabinopyranosyl-β- d -glucopyranoside (linalyl β-vicianoside: LinVic) was synthesized, and a linalool diglycoside purified from soybean leaves was identified as LinVic by using liquid chromatography–mass spectrometry. High levels of LinVic were detected in leaves and sepals during soybean plant growth. The LinVic content did not significantly increase following methyl jasmonate treatment of the leaves, indicating that its synthesis is independent of the jasmonic acid signaling pathway. In addition to LinVic, soybean also contains 1-octen-3-yl primeveroside. We treated soybean leaves with vaporized linalool and 1-octen-3-ol to determine whether the glycosylation system discriminates between these 2 volatile alcohols. Linalool treatment resulted in the accumulation of LinVic, while 1-octen-3-ol treatment caused little change in the amount of 1-octen-3-yl primeveroside, suggesting discrimination between these compounds. Linalool-treated soybean leaves exhibited increased resistance against common cutworms, indicating that LinVic may contribute to herbivore resistance. [ABSTRACT FROM AUTHOR]

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), has a long association with maize (Zea mays mays L., Poaceae) and is among the crop's most significant pests worldwide. We contrasted the preference for and performance of FAW on three maize cultivars: the Mexican landrace Tuxpeño, the USA inbred B73 and B73‐lox10; B73‐lox10 is deficient in production of jasmonic acid (JA), green leaf volatiles (GLVs) and herbivore‐induced plant volatiles (HIPVs). Female oviposition and neonate colonization preferences were assessed in triple‐choice tests in greenhouse settings. Performance was assessed on the bases of larval, pupal and adult weights, larval and pupal development times, and adult longevity. We expected females to preferentially oviposit on plants on which their offspring performed best, and neonates to randomly colonize plants because they disperse aerially, presumably oriented solely by wind currents. Females preferred to oviposit on Tuxpeño plants, followed by B73‐lox10 and B73 plants, whereas their offspring performed best on B73‐lox10 and poorest on Tuxpeño. In contrast, neonates preferentially colonized plants on which they performed best, B73‐lox10, though initially and transiently they colonized plants on which they performed poorly, B73 and Tuxpeño. Altogether, our results showed that FAW females preferred to oviposit on maize plants on which their offspring's performance was poorest (Tuxpeño), and neonates preferentially colonized plants on which their own performance was best (B73‐lox10), though they initially colonized plants that were detrimental to their performance (Tuxpeño, B73). These results suggested that the ovipositional choices of FAW mothers are uncoupled from their offspring's performance, but newborn offspring rectified their mother's sub‐optimal host plant choice by colonizing plants that enhanced their own performance. Notably, these results also suggested that aerially dispersing (ballooning) FAW larvae do not colonize plants randomly, and that plant volatiles (GLVs, HIPVs) and JA may be relevant to host plant selection by ballooning larvae. [ABSTRACT FROM AUTHOR]

Summary: Here, we investigated the molecular genetic basis of mite domatia, structures on the underside of leaves that house mutualistic mites, and intraspecific variation in domatia size in Vitis riparia (riverbank grape).Domatia and leaf traits were measured, and the transcriptomes of mite domatia from two genotypes of V. riparia with distinct domatia sizes were sequenced to investigate the molecular genetic pathways that regulate domatia development and intraspecific variation in domatia traits.Key trichome regulators as well as auxin and jasmonic acid are involved in domatia development. Genes involved in cell wall biosynthesis, biotic interactions, and molecule transport/metabolism are upregulated in domatia, consistent with their role in domatia development and function.This work is one of the first to date that provides insight into the molecular genetic bases of mite domatia. We identified key genetic pathways involved in domatia development and function, and uncovered unexpected pathways that provide an avenue for future investigation. We also found that intraspecific variation in domatia size in V. riparia seems to be driven by differences in overall leaf development between genotypes. [ABSTRACT FROM AUTHOR]

The article explores the impact of leaf mining on the chemical defense of a Late Triassic ginkgophyte plant using ATR-FTIR analysis. Leaf mining by insect larvae can lead to increased water and nutrient loss, reduced photosynthesis, and altered plant defenses. The study found that leaf mining induced chemical changes in both modern and fossil leaves, with evidence of plant defense responses to leaf mining detected through chemical analysis. The research sheds light on the co-evolutionary dynamics between plants and insects in ancient ecosystems and highlights the potential of chemical analysis in understanding plant defenses in deep time. [Extracted from the article]

Powdery mildew and stripe rust are major diseases on wheat worldwide that cause significant reductions in wheat production. The ribosomal silencing factor (RsfS) has been proven to regulate protein biosynthesis by inhibiting the translation process in bacterial response to stress. However, the role of RsfS in plant resistance to biotic stresses remains unclear. In this study, the RsfS homolog, TaRsfS was isolated from wheat. Overexpression of TaRsfS (TaRsfS‐OE) reduces wheat resistance to powdery mildew and stripe rust and TaRsfS knockout (TaRsfS‐KO) increases wheat resistance to both diseases without affecting key agronomic traits. The interaction protein of TaRsfS, 12‐oxo‐phytodienoic acid reductase 1 (TaOPR1), a key enzyme in the biosynthesis of jasmonic acid (JA), was screened and identified. Knocking‐down and overexpression of TaOPR1 indicated that TaOPR1 positively regulates wheat resistance to powdery mildew and stripe rust. TaRsfS may regulate TaOPR1 at upstream, bind to the enzyme activity pocket of TaOPR1 and affect TaOPR1 enzyme activity, resulting in a reduced JA biosynthesis and wheat susceptible to powdery mildew and stripe rust. Collectively, TaRsfS is a susceptibility gene and negatively regulates wheat resistance to powdery mildew and stripe rust, and it has good potential for improving wheat resistance by genetic modifications. Summary statement: A susceptible factor TaRsfS was identified in wheat, which interacted and down‐regulated the enzyme activity of TaOPR1, resulting in a reduction of the synthesis of JA and wheat susceptible to powdery mildew and stripe rust. Inactivation of TaRsfS confers resistance to both diseases without affecting key agronomic traits. [ABSTRACT FROM AUTHOR]

Drought is an important abiotic factor constricting crop production globally. Although the roles of JAZ proteins in regulating jasmonic acid signalling and plant responses to environmental stress are well documented, their specific functions and underlying mechanisms remain little known. In this study, JAZ proteins in barley were thoroughly analyzed, revealing a total of 11 members classified into three phylogenetic subgroups. HvJAZ2, based on its distinct expression patterns, is considered a key candidate gene for regulating drought tolerance in barley. Using the HvJAZ2 knockout mutants, we revealed that the gene negatively regulates drought tolerance by inhibiting barley root growth. Notably, the jaz2 mutants upregulated the expression of root development genes, including SHR1, PLT1, PLT2 and PLT6. plt2 and plt1/plt2 mutants exhibited suppressed root development and reduced drought tolerance. Analysis of interactions between HvJAZ2 and other proteins showed that HvJAZ2 does not directly interact with HvPLT1/2/6, but interacts with some other proteins. BIFC and LCA assays further confirmed the nuclear interaction between HvJAZ2 and HvMYC2. Y1H and Dual‐Luciferase experiments demonstrated that HvMYC2 can bind to and activate the HvPLT2 promoter. In summary, HvJAZ2 negatively regulates root development and drought tolerance in barley by suppressing HvPLT2 expression through interacting with HvMYC2. Summary statement: Drought is a major abiotic factor limiting crop production globally.This study found HvJAZ2 negatively regulates drought tolerance in barley (Hordeum vulgare L.) by suppressing HvPLT2 expression through interacting with HvMYC2, which is potentially useful for improving barley's drought tolerance. [ABSTRACT FROM AUTHOR]

Verticillium wilt (VW) caused by the soil‐borne fungal pathogen Verticillium dahliae reduces cotton productivity and quality. Numerous studies have explored the genetic and molecular mechanisms regulating VW resistance in cotton, but the role and mechanism of strigolactone (SL) is still elusive. We investigated the function of SL in cotton's immune response to V. dahliae infection by exogenously applying SL analog, blocking or enhancing biosynthesis of endogenous SLs in combination with comparative transcriptome analysis and by exploring cross‐talk between SL and other phytohormones. Silencing GhDWARF27 and applying the SL analog GR24 or overexpressing GhDWARF27 decreased and enhanced V. dahliae resistance, respectively. Transcriptome analysis revealed SL‐mediated activation of abscisic acid (ABA) and jasmonic acid (JA) biosynthesis and signaling pathways. Enhanced ABA biosynthesis and signaling led to increased activity of antioxidant enzymes and reduced buildup of excess reactive oxygen species. Enhanced JA biosynthesis and signaling facilitated transcription of JA–dependent disease resistance genes. One of the components of the SL signal transduction pathway, GhD53, was found to interact with GhNCED5 and GhLOX2, the key enzymes of ABA and JA biosynthesis, respectively. We revealed the molecular mechanism underlying SL–enabled V. dahliae resistance and provided potential solutions for improving VW resistance in cotton. Summary statement: VW caused by Verticillium dahliae reduces cotton productivity and quality. Our study demonstrated that SLs are positive regulators of V. dahliae resistance, established the cross‐talk relationship between SLs and JA/ABA and provided insight into the molecular mechanism underlying SL–mediated disease resistance. [ABSTRACT FROM AUTHOR]

Plants have developed various resistance mechanisms against herbivorous insects through prolonged coevolution. Plant defence responses can be triggered by specific compounds present in insect saliva. Apyrase, a known enzyme that catalyzes the hydrolysis of adenosine triphosphate (ATP) and adenosine diphosphate (ADP) into adenosine monophosphate (AMP) and inorganic phosphorus, has recently been identified in some herbivorous insects. However, whether insect salivary apyrase induces or inhibits plant responses remains poorly understood. In this study, we identified an apyrase‐like protein in the salivary proteome of the fall armyworm, Spodoptera frugiperda, named Sfapyrase. Sfapyrase was primarily expressed in the salivary gland and secreted into plants during insect feeding. Transient expression of Sfapyrase in tobacco and maize enhanced plant resistance and resulted in decreased insect feeding. Knockdown of Sfapyrase through RNA interference led to increased growth and feeding of S. frugiperda. Furthermore, we showed that Sfapyrase activates the jasmonic acid signalling pathway and promotes the synthesis of secondary metabolites, especially benzoxazinoids, thereby enhancing resistance to S. frugiperda. In summary, our findings demonstrated that Sfapyrase acts as a salivary elicitor, inducing maize jasmonic acid defence responses and the production of insect‐resistant benzoxazinoids. This study provides valuable insights into plant–insect interactions and offers potential targets for developing innovative insect pest management strategies. Summary statement: We have characterized SfApyrase from Spodoptera frugiperda as a salivary elicitor secereted into host plants via feeding. Specifically, it stimulates the JA‐mediated signalling pathway, leading to the upregulation of defence‐related genes, such as terpene and benzoxazinoid biosynthetic genes, thereby triggering plant defence. These findings provide novel insights into the diverse functions of apyrase in insect and plant interactions across different insect species. Furthermore, the identified SfApyrase presents a potential substance for inducing plant immunity, offering promising applications in future pest management strategies. [ABSTRACT FROM AUTHOR]

BACKGROUND: Methyl jasmonate (MeJA) can affect the balance of hormones and regulate the disease resistance of plants. Exploring the application and mechanism of MeJA in inducing the tolerance of Pinus koraiensis to pine wood nematode (PWN) infection is of great significance for developing new strategies for pine wilt disease control. RESULTS: Different concentrations (0.1, 1, 5 and 10 mm) of MeJA treatment groups showed differences in relative tolerance index and relative anti‐nematode index of P. koraiensis seedlings to PWN infection. The treatment of 5 mm MeJA solution induced the best tolerance effect, followed by the 1 mm MeJA solution. Transcriptome analysis indicated that many plant defense‐related genes upregulated after treatment with 1, 5 and 10 mm MeJA solutions. Among them, genes such as jasmonate ZIM domain‐containing protein, phenylalanine ammonia‐lyase and peroxidase also continuously upregulated after PWN infection. Metabolome analysis indicated that jasmonic acid (JA) was significantly increased at 7 days postinoculation with PWN, and after treatment with both 1 and 5 mm MeJA solutions. Integrated analysis of transcriptome and metabolome indicated that differences in JA accumulation might lead to ubiquitin‐mediated proteolysis, and expression changes in trans‐caffeic acid and trans‐cinnamic acid‐related genes, leading to the abundance differences of these two metabolisms and the formation of multiple lignin and glucosides. CONCLUSIONS: MeJA treatment could activate the expression of defense‐related genes that correlated with JA, regulate the abundance of defense‐related secondary metabolites, and improve the tolerance of P. koraiensis seedlings to PWN infection. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: The western flower thrips (WFT), Frankliniella occidentalis (Thysanoptera: Thripidae), is a significant pest in horticulture and ornamental agriculture. While exogenous calcium (Ca) has been shown to confer plant immune responses against thrips, the detailed mechanisms of this interaction remain to be elucidated for improved thrips management strategies. This study aimed to assess the impact of exogenous Ca on WFT feeding behavior and to explore its role in enhancing the defense mechanisms of kidney bean plants against WFT attacks. We compared WFT feeding preferences and efficiency on kidney bean plants treated with H2O or Ca, and examined whether exogenous Ca improves plant defense responses to thrips attack. RESULTS: WFT exhibited less preference for feeding on Ca‐treated plants over H2O‐treated ones. The total duration of WFT's long‐ingestion probes was significantly reduced on Ca‐treated plants, indicating impaired feeding efficiency. Furthermore, WFT infestation activated both jasmonic acid (JA) and salicylic acid (SA) signaling pathways in kidney bean plants, and exogenous Ca application led to elevated levels of endogenous Ca2+ and CaM, up‐regulation of genes associated with JA and SA pathways (LOX, AOS, PAL, and β‐1,3‐glucanase), and increased accumulation of JA, SA, flavonoids, and alkaloids. CONCLUSION: Our findings demonstrate that the application of exogenous Ca enhances endogenous Ca2+, JA, and SA signaling pathways in kidney bean plants. This enhancement results in an up‐regulation of the biosynthesis of flavonoid and alkaloid, thereby equipping the plants with an enhanced defense against WFT infestation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: 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 24 h pos-treatment in the transcript level of 8 traditional genes selected for molecular studies plant–pathogen interactions in Capsicum. Methods and results: Chemical treatment was achieved by spraying leaves of in vitro seedlings C. annuum L. with 0.1 mM, 1 mM or 2.5 mM ET; 1 mM, 2.5 mM, or 5 mM SA; 2.5 mM BABA; or 0.150 mM MeJA. Twenty-four hours after treatments were applied molecular analyses were carried out using qPCR to investigate the expression. Results revealed that 1 mM of ET or 0.15 mM 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, 5 mM of SA present effect of negative regulation on the expression in most of these genes. Conclusions: 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. [ABSTRACT FROM AUTHOR]

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Effector proteins secreted via the type III secretion system (T3SS) of nitrogen-fixing rhizobia are key determinants of symbiotic compatibility in legumes. Previous report revealed that the T3SS of Bradyrhizobium sp. DOA9 plays negative effects on Arachis hypogaea symbiosis. In this study, we characterized the symbiotic role of 4 effector proteins (p0490, p0871, SkP48, and p0903) containing the small ubiquitin-like modifier (SUMO) protease domain identified in DOA9 during symbiosis. While the DOA9 strain and the two mutants of SUMO-proteases, p0490 and p0871, induced inefficient nodulation in A. hypogaea, the mutation of SUMO-proteases SkP48 or p0903 promoted efficient symbiosis comparable to the type strain Bradyrhizobium arachidis CCBAU051107. Complementation study of ∆p0903 with various mutated forms of p0903 highlighted importance of ubiquitin-like protein (ULP) domain in restriction of nodulation in A. hypogaea. We observed the accumulation of jasmonic acid (JA) and upregulation of several defence genes involved in the JA/ethylene (ET) signalling pathway at the early stage of infection in roots inoculated with DOA9 strain compared with those inoculated with the DOA9-∆p0903 strain. Our data highlight the importance of SUMO-protease effectors during the symbiotic interaction between bradyrhizobia and A. hypogaea, which could be useful for the development of high-performance inocula to improve its growth. [ABSTRACT FROM AUTHOR]

ABSTRACT Land plants use diverse hormones to coordinate their growth, development and responses against biotic and abiotic stresses. Salicylic acid (SA) is an essential hormone in plant immunity, with its levels and signaling tightly regulated to ensure a balanced immune output. Over the past three decades, molecular genetic analyses performed primarily in Arabidopsis have elucidated the biosynthesis and signal transduction pathways of key plant hormones, including abscisic acid, jasmonic acid, ethylene, auxin, cytokinin, brassinosteroids, and gibberellin. Crosstalk between different hormones has become a major focus in plant biology with the goal of obtaining a full picture of the plant hormone signaling network. This review highlights the roles of SA in plant immunity and summarizes our current understanding of the pairwise interactions of SA with other major plant hormones. The complexity of these interactions is discussed, with the hope of stimulating research to address existing knowledge gaps in hormone crosstalk, particularly in the context of balancing plant growth and defense. [ABSTRACT FROM AUTHOR]

Background: Alfalfa, scientifically identified as Medicago sativa , is repeatedly referred to as the "king of forages". Because of its tight relationship to winter hardiness, the alfalfa's root crown plays a significant role as a storage organ over the winter. At present, it is still unknown what molecular process makes the alfalfa root crown resistant to cold. This study was aimed to study these knowledge gaps. Using RNA sequencing (RNA-Seq) technology, significant genes associated with cold hardiness were found. Methods: According to the random block design, Longmu 806 alfalfa and Sardi alfalfa were planted in regional experiments. Under the condition of low-temperature treatment in winter, the differentially expressed genes (DEGs), winter survival rate (WSR), and physiological characteristics were, in turn, calculated by RNA-Seq, chemical analysis, and field investigation. Results: The WSR of the Longmu 806 alfalfa was 3.68-fold greater than that of the Sardi alfalfa. The jasmonic acid (JA), soluble sugar (SS), proline (Pro), and glutathione (GSH) concentration in the roots of Longmu 806 alfalfa was more than the same amount in Sardi alfalfa in other words P is less than 0.05. An entire set of 878 DEGs related to winter hardiness was found by statistical analysis. Among them, 463 DEGs showed an increase in expression, whereas 415 DEGs showed a decrease in expression. The metabolic pathways' examination presented that the DEGs (MsERF1, MsCHIB, MsJAZ, MsAOC, MsGST, MsINV , MsTPS , and MsOAT) were linked to the pathways of "plant hormone signaling transduction", "Amino sugar and nucleotide sugar metabolism", and "glutathione metabolism". Furthermore, the physiological changes in JA, SS, Pro content, and GSH were influenced by the dynamic transcription profile of LT (low- temperature) resistance-related genes. [ABSTRACT FROM AUTHOR]

SUMMARY: The glutamate receptor (GLR) serves as a ligand‐gated ion channel that plays a vital role in plant growth, development, and stress response. Nevertheless, research on GLRs in cotton is still very limited. The present study conducted a comprehensive analysis of GLRs gene family in cotton. In total, 41 members of the GLR family were identified in cotton unveiling distinct subgroups in comparison to Arabidopsis. Among these members, the third subgroup highlights its pivotal role in cotton's defense against insect infestation. Furthermore, the CRISPR/Cas9 system was utilized to create a mutant library of GLR members, which consisted of a total of 135 independent mutant lines, resulting in the production of novel cotton materials with valuable breeding potential for pest control. Further, this study elucidates the influence of GhGLR3.4 on jasmonic acid (JA) pathway signal transduction and demonstrated its participation in the influx of intracellular Ca2+, which regulates "calcium transients" following stimulation, thereby influencing multiple intracellular reactions. The study also found that GhGLR3.4 influences the synthesis of the JA pathway and actively partakes in long‐distance signal transmission among plants, facilitating the transfer of defense signals to neighbor leaves and thereby triggering systemic defense. Consequently, this research advances our knowledge of plants' comprehensive defense mechanism against insect pest infestation. [ABSTRACT FROM AUTHOR]

Summary Abscisic acid (ABA) and jasmonic acid (JA) are important plant hormones in response to drought stress. We have identified that ZmHsf28 elevated ABA and JA accumulation to confer drought tolerance in maize; however, the underlying mechanism still remains elusive. The knockout line zmhsf28 is generated to confirm the positive role of ZmHsf28 in drought response. Multiple approaches are combined to reveal protein interaction among ZmHsf28, ZmSnRK2.2 and ZmJAZ14/17, which form a regulatory module to mediate maize drought tolerance through regulating ABA and JA key biosynthetic genes ZmNCED3 and ZmLOX8. Upon drought stress, zmhsf28 plants exhibit weaker tolerance than the WT plants with slower stomatal closure and more reactive oxygen species accumulation. ZmHsf28 interacted with ZmSnRK2.2 physically, resulting in phosphorylation at Ser220, which enhances binding to the heat shock elements of ZmNECD3 and ZmLOX8 promoters and subsequent gene expression. Meanwhile, ZmMYC2 upregulates ZmHsf28 gene expression through acting on the G‐box of its promoter. Besides, ZmJAZ14/17 competitively interact with ZmHsf28 to interfere with protein interaction between ZmHsf28 and ZmSnRK2.2, blocking ZmHsf28 phosphorylation and impairing downstream gene regulation. The ZmSnRK2.2‐ZmHsf28‐ZmJAZ14/17 module is identified to regulate drought tolerance through coordinating ABA and JA signaling, providing the insights for breeding to improve drought resistance in maize. [ABSTRACT FROM AUTHOR]

Summary: Pathogenic fungi such as Valsa mali secrete effector proteins to manipulate host defenses and facilitate infection. Subtilases are identified as potential virulence factors, yet their specific roles in fruit tree pathogens, such as those affecting apple trees, are poorly understood.Our research shows VmSpm1 as a virulence factor in V. mali. Knocking it out decreased virulence, whereas its heterologous expression in apple led to reduced disease resistance.Using Y2H, BiFC, SLC, and Co‐IP techniques, we demonstrated an interaction between VmSpm1 and MdPYL4. MdPYL4 levels increased during V. mali infection. The stable transgenic apple lines inoculation experiment showed that MdPYL4 correlates with enhanced resistance to Apple Valsa canker when overexpressed in apples. Furthermore, through in vitro and in vivo assays, we showed the degradative role of VmSpm1 on MdPYL4. MdPYL4 promotes the synthesis of jasmonic acid (JA) in apples in an abscisic acid‐dependent manner. The degradation of MdPYL4 leads to a reduction in JA content in apples during V. mali infection, thereby impairing JA signal transduction and decreasing disease resistance in apple plants.In summary, this study reveals how V. mali utilizes VmSpm1 to subvert JA signaling, shedding light on fungal manipulation of plant hormones to disrupt immunity. [ABSTRACT FROM AUTHOR]

Flooding causes severe yield losses worldwide, making it urgent to enhance crop tolerance to this stress. Since natural flooding often involves physical flow, we hypothesized that the effects of submergence on plants could change when combined with physical flow. In this study, we analyzed the growth and transcriptome of Arabidopsis thaliana exposed to submergence or flooding with physical flow. Plants exposed to flooding with physical flow had smaller rosette diameters, especially at faster flow rates. Transcriptome analysis revealed that "defense response" transcripts were highly up-regulated in response to flooding with physical flow. In addition, up-regulation of transcripts encoding ROS-producing enzymes, SA synthesis, JA synthesis, and ethylene signaling was more pronounced under flooding with physical flow when compared to submergence. Although H2O2 accumulation changed in response to submergence or flooding with physical flow, it did not lead to lipid peroxidation, suggesting a role for ROS as signaling molecules under these conditions. Multiple regression analysis indicated possible links between rosette diameter under flooding with physical flow and the expression of Rbohs and SA synthesis transcripts. These findings suggest that pathogen defense responses, regulated by SA and ROS signaling, play crucial roles in plant responses to flooding with physical flow. [ABSTRACT FROM AUTHOR]

Tomato spotted wilt orthotospovirus (TSWV) is one of the most destructive pathogens and causes serious losses in agriculture worldwide. Biogenic pesticides application may be an effective approach for defending against TSWV. Tagitinin A (Tag A) extracted from Tithonia diversifolia (Hemsl.) A. Gray has a high protective effect against TSWV infection. Tag A can induce jasmonic acid to suppress gene expression in TSWV. In this study, the F-box protein (CPR30) was mediated by Tag A, the expression of the CPR30 gene in Tag A-treated leaves was significantly higher (2 times) than that of the negative control. Furthermore, the replication of TSWV-NSm/NSs genes and the expression of TSWV-NSm/NSs proteins significantly increased after silencing the CPR30 gene in protective assays; CPR30 overexpression showed the opposite tendency. The CPR30 protein only localized and interacted with the TSWV-NSm protein. Thus, this study reveals a new mechanism by which Tag A mediates ubiquitin–protein ligase E3 (CPR30) to interact with NSm inhibite NSm replication and expression, and defend against systemic TSWV infection. [ABSTRACT FROM AUTHOR]

A fire and explosion accident at a petrochemical complex sparked concerns over the rice health and production in nearby paddy fields. To unveil the potential effects, this study investigated small molecule changes in rice harvested in nearby counties using non-target analysis. Rice grains were harvested three, eight, 15, and 20 months after the accident from a total of ten townships. Small-molecule (m/z 70–1100) data in brown rice (n = 27) were acquired using high-resolution mass spectrometry (HRMS). Partial least squares discriminant analysis (PLS-DA) models were constructed to illustrate the temporal and spatial trends of rice's small-molecule fingerprints, and markers of production locations were identified. The small-molecule fingerprint in the rice directly exposed to the accident and harvested three months after the explosion differed significantly from those planted after the accident (PLS-DA model Q2 = 0.943, Q2/R2Y = 0.962), probably indicating the exclusion of long-term effects. Besides, in the rice directly exposed to the accident, the rice collected from near the explosion site (< 15 km) exhibited reduced jasmonic acid and increased imidacloprid levels (log2 fold change: -1.53 and 5.46, respectively), compared to that from farther locations. The result would suggest compromised disease defence in rice grown under the stress of explosion. In addition, lipid and amino acid metabolism perturbations are deemed relevant to plant development. [ABSTRACT FROM AUTHOR]

Interactions between jasmonic acid (JA) and salicylic acid (SA) pathways in plants are important for regulating metabolite production and resistance functions against environmental stresses. These interactions in plants have mostly been reported to be antagonistic, but also to be synergistic under specific external inducing conditions. At present, publications on plant JA–SA interactions lack a bibliometric analysis. External inducing factors that elicit synergism of JA–SA interactions need to be explored. Here, we use bibliometrics to analyze publications on plant JA–SA interactions over the past three decades, and analyze external inducing factors that influence the quality of JA–SA interactions in plants by meta-analysis. More contributions have been made by authors in China, Netherlands, the United States of America, and Germany than elsewhere. Considerable research has been performed on variation in plant defense mediated by two pathways, the transduction mechanisms of JA–SA signaling crosstalk, and plant hormone signaling networks. Meta-analysis showed that the excitation sequence of the two pathways, and the concentrations of pathway excitors are key factors that affect pathways interactions. The JA and SA pathways tend to be reciprocally antagonistic when elicited simultaneously, whereas JA–SA interactions tend to be synergistic when the two pathways are elicited at different times and the pre-treated inducer is at a lower concentration. The SA pathway is more susceptible to being synergized by the JA pathway. Key molecular nodes identified in the JA–SA signaling interaction in model plants, and prospects for future research are discussed. [ABSTRACT FROM AUTHOR]

Introduction: Inducing natural resistance against pathogen infection in postharvest tomatoes is a sustainable strategy for reducing postharvest losses. The action model underlying the resistance enhancement of tomatoes induced by bacterial volatile organic compounds (VOCs) against Botrytis cinerea , however, have not been explored. Methods: In this study, RNA-seq, metabolomics and physiological analysis were used to evaluate global change of defense response induced by VOCs in tomatoes. Results: The application of VOCs inhibited the damage to tomatoes caused by B. cinerea. VOCs treatment had remarkable beneficial effects on the activities of the main defence-related enzymes, including chitinases, glucanases, peroxidases, ascorbate peroxidases, polyphenol oxidases, and phenylalanine ammonia-lyases. The expression of response genes involved in salicylic acid and jasmonic acid biosynthesis and signalling pathways was enhanced upon VOCs treatment. Metabolomics data demonstrated that VOC treatment triggered the accumulation of phenolic acids, including substrates in phenolic acid biosynthesis pathways, hydroxycinnamic acid, hydroxybenzoic acid, and their derivatives. Transcriptomics analysis and qRT-PCR verification revealed that VOCs treatment significantly upregulates the expression of core genes related to phenolic acid biosynthesis, specifically in shikimate pathway (SlDAHPS , SlSDH , SlCS , and SlADT3) and phenylalanine metabolic pathway (SlPAL , Sl4CL , SlBAHD1 , SlCYP98A2 and SlCAP84A1). Discussion: Results confirmed that VOCs enhanced tomatoes postharvest resistance against B. cinerea by regulating defence enzyme activity, SA/JA signalling, and phenolic acid biosynthesis pathway. This study provides new insights into the mechanisms by which VOCs fumigation manages postharvest grey mould in tomatoes. [ABSTRACT FROM AUTHOR]

In Arabidopsis thaliana, the transcription factors WRKY7, WRKY11 and WRKY17 act as negative defence regulators against Pseudomonas syringae pv. tomato (Pst) DC3000. However, their coordinated regulation of gene expression has yet to be fully explored. In this study, we conducted a transcriptomic analysis on the triple mutant wrky7/11/17 in response to Pst DC3000 at 0, 3 and 24 h post‐inoculation (hpi). Our results suggest that at early infection stages (0 and 3 hpi), WRKY7, WRKY11 and WRKY17 significantly repress a group of genes involved in signal perception and transduction, including receptor‐like kinases. Furthermore, at later stages of interaction (24 hpi), these transcription factors induce genes related to the biosynthesis and signalling of the jasmonic acid (JA) pathway. Further infection experiments with Pst DC3000 in plants treated with methyl jasmonate (a JA analogue) and infections with Botrytis cinerea, a pathogen against which JA‐mediated responses are crucial for effective defence, support this proposal. Moreover, we analysed the role of WRKY7, WRKY11 and WRKY17 in alternative splicing regulation. A comparison between differentially expressed (DEG) and spliced (DAS) genes revealed that over 80% of DAS events do not occur in conjunction with overall changes in gene expression. Alternative splicing events were found in genes with functions in splicing and the JA pathway, such as ALY4, PRP40A, JAZ3 and JAZ10. These results suggest that WRKY7, WRKY11 and WRKY17 can also participate in this layer of gene expression regulation to modulate immunity negatively. [ABSTRACT FROM AUTHOR]

Autophagy, one of the most widespread and highly conserved protein degradation systems in eukaryotic cells, plays an important role in plant growth, development and stress response. Beclin 1 is a core component of the phosphatidylinositol 3‐kinase (PI3K) autophagy complex and positively regulates plant immunity against viruses. The upregulation of Eureka lemon ClBeclin1 was observed in response to citrus yellow vein clearing virus (CYVCV) infection. However, the function of ClBeclin1 and the underlying mechanism during CYVCV colonisation remain unclear. Here, the resistance evaluation of the overexpression and silencing of ClBeclin1 in Eureka lemon hairy roots revealed it as a positive regulator of citrus immunity against CYVCV. Transcriptomic profiling and metabolic analyses along with genetic evidence implied that the overexpression of ClBeclin1 positively triggered reactive oxygen species (ROS)‐ and jasmonic acid (JA)‐mediated immunity in citrus. The accumulation of ROS and JA contents was attributed to the autophagic degradation of the ROS scavenger ClAPX1 via ClBeclin1 overexpression. Exogenous application of either H2O2 or JA significantly reduced CYVCV colonisation and vein‐clearing symptoms on the host. Collectively, our findings indicate that ClBeclin1 activation contributes to citrus immunity against CYVCV through triggering ROS‐ and JA‐mediated defence responses, and the accumulation of ROS and JA resulted from the autophagic degradation of ClAPX1 by ClBeclin1. [ABSTRACT FROM AUTHOR]

Aims: The aims of this work were to investigate phosphate starvation responses of Brassica napus (B. napus) under heterogeneous phosphate (Pi) supply and the regulatory role of jasmonic acid (JA) in the systemic response to Pi starvation. Methods: A split-root system with two separated compartments was employed to mimic heterogeneous Pi distribution in the soil and to examine the effect of heterogeneous Pi supply, and JA or DIECA (JA biosynthesis inhibitor) on growth, root morphology, Pi concentration, Acid phosphatase (APase) activity, nutrition uptake, JA concentration and expression of Pi starvation systemically-induced (PSSI) genes of B. napus. Results: Heterogeneous Pi supply systemically modified root morphology that increased the total root surface area (TRSA), total root volume (TRV), total root length (TRL) and total lateral root number (TLRN) of root with local Pi supply (R +) and decreased them of root with local no Pi supply (R-) when compared to root with homogeneous Pi supply (R + +) and root devoid of Pi (R–), respectively. Anthocyanin, APase activity and JA concentration in shoot and root of B. napus were systemically regulated by heterogeneous Pi supply. In addition, heterogeneous Pi supply significantly promoted nutrient uptake when compared with homogeneous no Pi supply. Root morphology of B. napus was significantly changed by exogenous addition of JA or DIECA in a split-root system. JA enhanced Pi starvation response by inducing expression of PSSI genes in shoots and roots. Conclusions: Our results suggest that JA enhances systemic Pi starvation response of B. napus by regulating root morphology, Pi homeostasis and inducing expression of PSSI genes under heterogeneous Pi supply. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is an indispensable macronutrient serving a variety of functions in plants. Inositol pyrophosphates (PP-InsPs) nutrient messengers play vital roles in the signaling of P status and plant growth and development. In this review, we summarize (1) the biosynthetic pathway of PP-InsPs and their regulation by plant P status, (2) the effects of PP-InsPs on the function of the SPX domain-containing proteins in signaling plant P status, (3) the effects of inositol pyrophosphates on auxin signaling through TIR1 and on jasmonate signaling through COI1, and (4) the potential crosstalk between P status signaling and phytohormone signaling in plants mediated by inositol pyrophosphates. It is concluded that the interactions between inositol pyrophosphates and their binding proteins are central to plant P status and developmental responses to different P supply. [ABSTRACT FROM AUTHOR]

Background/Objectives: Skin wrinkles result from a myriad of multifaceted processes involving intrinsic and extrinsic aging. To combat this effect, plant stem cells offer a renewable and eco-friendly source for various industries, including cosmeceuticals. Salvia miltiorrhiza (SM), which contains the bioactive compound Rosmarinic acid (RA) and has been proposed for its anti-wrinkle effect. Methods: In the present study, calli from SM were cultured and Quality by Design (QbD) was implemented to investigate the effect of different types and concentrations of elicitors; jasmonic acid (JA) and salicylic acid (SA). Both raised RA levels yet, jasmonic acid (50 µM) has resulted in the highest yield for RA, at 16 mg/g. A nanofiber patch was prepared and characterized in-vitro by the release percentage, drug content, swelling degree, scanning electron microscope, and surface roughness. Then, the anti-wrinkle effect of the patch was tested in a UV wrinkle-induced mouse model. Results: Interestingly, after treatment, there were visibly fewer wrinkles, and the skin was softer than in the untreated control group. This study suggests that the treatment exerted its effect through the Nrf2/Keap1 pathway, which plays a crucial role in cellular antioxidant protective processes. By activating this pathway through boosting Nrf2 and diminishing Keap1 cellular content, the nanofiber patch enhances the production of antioxidant enzymes, such as superoxide dismutase and glutathione peroxidase, enhancesglutathione, and reduces the skin lipid peroxidation, collectively indicating enhanced skin quality. Conclusions: In conclusion, this study highlights the importance of this formula as an anti-wrinkle treatment, and future clinical studies are recommended to further unveil the potential of this formula. [ABSTRACT FROM AUTHOR]

Background: Mirabilis himalaica, distributed in the high-altitude, arid, and semi-arid regions of Xizang, exhibits great tolerance to drought, which is rich in rotenoids and other secondary metabolites. It is still unknown, though, how drought stress influences rotenoid synthesis in M. himalaica. Methods: In this study, the calli of M. himalaica were subjected to 5% PEG6000 for 0, 20, and 40 h and divided into control group (CK), mild-drought-treated group (M), and high-drought-treated group (H), respectively. We then analyzed the relative content of three main rotenoids in M. himalaica using high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC-ESI-MS/MS). Results: Our findings demonstrated that the content of rotenoids was significantly reduced under drought stress. Transcriptome analysis subsequently revealed 14,525 differentially expressed genes (DEGs) between the different treatments. Furthermore, these DEGs exhibited enrichment in pathways associated with isoflavone biosynthesis and hormone signaling pathways. Key genes with decreased expression patterns during drought stress were also found to be involved in rotenoid accumulation and drought-responsive phytohormone signaling, including abscisic acid (ABA), auxin (IAA), and jasmonic acid (JA). Conclusions: These findings elucidate the molecular processes of drought resistance in M. himalaica and shed light on the relationship between rotenoid production and drought stress in M. himalaica. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress is a cellular condition induced by environmental stressors. Transcriptomic approaches reveal the response of plants to ER stress and provide a broadened view. Tomato plants were treated with tunicamycin, and total RNA isolated from the tomato leaves was sequenced on an RNA-sequencing platform to be analyzed for differential expressions. A total of 856 differentially expressed genes (DEGs) were discovered in tunicamycin-treated tomato leaves. Upregulation of ER stress marker gene expressions was detected after 2h, while a prolonged ER stress downregulated most of the protein-coding genes. Pathways such as: response to stress, jasmonic acid mediated signaling, signal transduction regulation, plant hormone signal transduction, and protein processing in ER were enriched. Prolonged stress mostly resulted in reduced transcript levels, possibly related to a mechanism functioning to lower the load of nascent transcripts in the ER. Our findings emphasize the key role of JA-regulated signaling in tomato ER stress responses due to the differential expressions of the pathway components, along with other plant hormones and signaling-related or regulatory genes. ER stress being a common response to many stressors in plants, transcriptome data obtained here will provide for further studies of understanding plant stress tolerance or generating stress-resistant tomato plants. [ABSTRACT FROM AUTHOR]

Intensive agriculture often comes at the expense of soil health. A shift towards practices that foster soil health will support yield and defences against pests and diseases. Growing crops in monoculture is the standard in modern agriculture, though strip‐cropping, in which different crops are planted in strips, is a promising strategy in the transition towards sustainable agriculture. Increasing crop diversity is hypothesized to positively influence arbuscular mycorrhizal fungi (AMF), thereby enhancing soil health, but the mechanisms by which AMF‐plant symbioses contribute to higher yields and reduced pest populations in strip‐cropping systems remain unclear.We used a green‐house experiment with potato plants to explore the soil legacy effects of mono‐cropping versus strip‐cropping systems, AMF inoculation and aphid infestation on AMF root colonization, the induction of plant defences (untargeted LCMS‐based metabolomics), aphid population size and potato yield.We found that potato plants grown in strip‐cropping soil had higher AMF colonization than plants grown in mono‐cropping soil. Potato plants grown in strip‐cropping soil also had higher shoot nitrogen content, increased solamargine levels, and reduced aphid populations. AMF root colonization was only enhanced by the addition of commercial AMF in mono‐cropping soils. Potato plant metabolites were affected by strip‐cropping soil, including jasmonic acid (JA) derivatives. Structural equation models revealed that strip‐cropping soil directly reduced aphid populations and also had a negative direct effect on the JA precursor OPC‐8, and hydroxyJA‐glucosides, indicating complex effects of strip‐cropping soils on JA‐inducible plant defences. Indirect benefits of strip‐cropping soil and AMF inoculation on tuber yield were mediated by their direct positive effects on plant nitrogen content.Our results emphasize the potential of strip‐cropping to enhance AMF root colonization in the field. We show that soil legacy effects of strip‐cropping alter the plant metabolome in ways that suppress of aphid populations. Strip‐cropping legacy effects are the result of crop diversity, crop neighbour and edge effects resulting from crop management practices. While the mechanisms by which soil from strip‐cropping supresses pest populations still need to be identified, our study underscores the potential for strip‐cropping to enhance pest control and yield via soil mediated processes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Summary: Corn leaf aphids (Rhopalosiphum maidis) are highly destructive pests of maize (Zea mays) that threaten growth and seed yield, but resources for aphid resistance are scarce. Here, we identified an aphid‐resistant maize mutant, resistance to aphids 1 (rta1), which is allelic to LIGULELESS1 (LG1). We confirmed LG1's role in aphid resistance using the independent allele lg1‐2, allelism tests and LG1 overexpression lines. LG1 interacts with, and increases the stability of ZINC‐FINGER PROTEIN EXPRESSED IN INFLORESCENCE MERISTEM (ZIM1), a central component of the jasmonic acid (JA) signalling pathway, by disturbing its interaction with the F‐box protein CORONATINE INSENSITIVE 1a (COI1a). Natural variation in the LG1 promoter was associated with aphid resistance among inbred lines. Moreover, a loss‐of‐function mutant in the LG1‐related gene SPL8 in the dicot Arabidopsis thaliana conferred aphid resistance. This study revealed the aphid resistance mechanism of lg1, providing a theoretical basis and germplasm for breeding aphid‐resistant crops. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sanqi, the root of Panax notoginseng, has long been recognized for its therapeutic effects on cardiovascular diseases. Saponins, including ginsenosides and notoginsenosides, are the main bioactive components of P. notoginseng. The biosynthesis of saponins is closely related to the defense responses orchestrated by endogenous hormones. RESULTS: To provide new insights into the underlying role of phytohormone jasmonic acid (JA) in the synthesis and regulation of saponins, we performed an ultra‐performance liquid chromatography analysis of different tissues of P. notoginseng aged 2–4 years. Moreover, by combined evaluation of saponin content and transcriptome profiling of each tissue, the spatial and temporal distribution of saponins was analyzed. N notoginsenoside R1, ginsenoside Rb1 and ginsenoside Rd accumulated in the underground tissues, including the root, tuqi, fibril and rhizome. In agreement with this data, the corresponding genes of the endogenous hormone JAs, especially coronatine insensitive 1 (COI1) and myelocytomatosis proteins 2 (MYC2), were predominantly expressed in the underground tissues. The tissue‐ and age‐specific distribution of saponins was consistent with the expression of genes involved in JA biosynthetic, metabolic and signaling pathways. CONCLUSION: The present study has revealed the temporal and spatial effects of endogenous phtohormones in the synthesis and regulation of notoginsenosides, which will provide a significant impact on improving the ecological planting technology, cultivating new high‐quality varieties and protecting the rare resources of medicinal P. notoginseng. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

BACKGROUND: Late‐ripening citrus plays an important role in the stability of the global citrus industry. However, the regreening phenomenon in Valencia oranges impacts the peel color and commercial value. Ethylene degreening is an effective technique to improve the color of citrus fruits, but this effect may be delayed in regreened oranges. To better clarify this phenomenon, plastid morphology, pigment and phytohormone content in ethephon‐degreened Midknight Valencia oranges harvested in different stages were evaluated. RESULTS: Results showed that in fruits harvested at the turning stage, ethephon degreening treatment induced a chloroplast‐to‐chromoplast transition, and chlorophyll degradation and carotenoid accumulation were accelerated. Conversely, in fruits harvested at the regreening stage, the changes in plastid morphology were minimal, with delayed changes in chlorophyll and carotenoids. Genes related to ethylene biosynthesis and signaling pathways supported these responses. Variations in endogenous auxin, jasmonic acid, abscisic acid and gibberellins could partially explain this phenomenon. CONCLUSION: The response of Midknight Valencia oranges to ethephon degreening was delayed in the regreening stage, possibly due to the dynamic variations in endogenous phytohormones. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Key message: Candidate male sterility genes were identified in sugarcane, which interacts with kinase-related proteins, transcription factors, and plant hormone signaling pathways to regulate stamen and anther development. Saccharum officinarum is a cultivated sugarcane species that its predominant feature is high sucrose content in stems. Flowering is necessary for breeding new cultivars but will terminate plant growth and reduce sugar yield. The wild sugarcane species Saccharum spontaneum has robust and viable pollen, whereas most S. officinarum accessions are male sterile, which is a desirable trait of a maternal parent in sugarcane breeding. To study male sterility and related regulatory pathways in sugarcane, we carried out RNAseq using flowers in different developmental stages between male-sterile S. officinarum accession 'LA Purple' and fertile S. spontaneum accession 'SES208'. Gene expression profiles were used to detect how genes are differentially expressed between male sterile and fertile flowers and to identify candidate genes for male sterility. Weighted gene correlation networks analysis (WGCNA) was conducted to investigate the regulatory networks. Transcriptomic analyses showed that 988 genes and 2888 alleles were differentially expressed in S. officinarum compared to S. spontaneum. Ten differentially expressed genes and thirty alleles were identified as candidate genes and alleles for male sterility in sugarcane. The gene Sspon.03G0007630 and two alleles of the gene Sspon.08G0002270, Sspon.08G0002270-2B and Sspon.08G0014700-1A, were involved in the early stamen or carpel development stages, while the remaining genes were classified into the post-meiosis stage. Gibberellin, auxin, and jasmonic acid signaling pathways are involved in the stamen development in sugarcane. The results expanded our knowledge of male sterility-related genes in sugarcane and generated genomic resources to facilitate the selection of ideal maternal parents to improve breeding efficiency. [ABSTRACT FROM AUTHOR]

ALMT (aluminum-activated malate transporter) proteins play crucial roles in the transport of organic acids and have significant implications for plant stress responses and development. While extensively studied in some plants, the characteristics and functional divergence of the ALMT gene family have not yet been thoroughly explored in Prunus mume and some other Rosaceae species. In this study, we systematically analyzed the ALMT gene family across nine Rosaceae species to explore their evolutionary relationships, structural characteristics, and functional roles. A total of 138 ALMT genes were identified and categorized into four groups based on a phylogenetic analysis. The motif analysis confirmed the accuracy of the phylogenetic grouping. The collinearity analysis indicated that whole-genome duplication events were the primary drivers of ALMT gene expansion in these species. Furthermore, the cis-acting element analysis revealed diverse regulatory elements associated with environmental responses, including abscisic acid, light, and jasmonic acid. The gene expression correlation analysis showed that PmALMT1 is primarily associated with malic acid accumulation, whereas PmALMT8 is related to citric acid accumulation. Further transient expression in Nicotiana benthamiana validated the above conclusion. This comprehensive analysis provides valuable insights into the evolution, function, and regulation of the ALMT gene family in Rosaceae species. [ABSTRACT FROM AUTHOR]

Jasmonic acids, their effects on plant resistance and metabolites, have been extensively researched. However, methyl dihydrojasmonate (MDJ), a cost-effective and safe substitute for jasmonic acids, lacks sufficient research. This study presents a comprehensive analysis the impact of MDJ on Paris polyphylla var. yunnanensis. The present study aimed to enhance the accumulation of steroidal saponins (polyphyllin I, II, III, D, V, VI, VII, H) in Paris polyphylla var. yunnanensis which is a medicinal plant that contains medicinal steroidal saponins. To achieve this, different concentrations of MDJ were applied to Paris polyphylla var. yunnanensis. The study examined the impact of MDJ on physiology and polyphyllins. The optimal treatment concentration was identified, and the effects of MDJ on physiological metabolism and the expression pattern of related genes were explored. The results indicated that MDJ treatment significantly increased the levels of photosynthetic pigments, antioxidant enzymes, osmoregulators peaked at M2. Moreover, MDJ enhanced the accumulation of polyphyllins in both the leaves and rhizomes peaked at M2, particularly the sum of four polyphyllins (polyphyllin I, II, VI, VII) stated in the Chinese Pharmacopoeia, which increased by 45.65% following treatment. Based on transcriptome analysis, we revealed the polyphyllins-related genes by WGCNA. Furthermore, the majority of genes related to steroidal saponins were up-regulated following MDJ treatment. In the future, we recommend treating Paris polyphylla var. yunnanensis with suitable MDJ concentrations in production to efficiently enhance the yield of steroidal saponins. [ABSTRACT FROM AUTHOR]

Exotic plants can selectively recruit beneficial microorganisms, such as arbuscular mycorrhizal fungi (AMFs) and Bacillus spp., during their invasion process to enhance growth and competitiveness by improving nutrient absorption and strengthening defense capabilities against herbivores. However, research in the context of invasive plants remains limited. In this study, a greenhouse pot experiment was conducted to examine the effects of different treatments on the growth and defense of Ageratina adenophora. The treatments included no inoculation, inoculation with Bacillus thuringiensis (BT), inoculation with arbuscular mycorrhizal fungus (Claroideoglomus etunicatum, CE), dual inoculation with BT and CE (BT + CE), and the presence or absence of Procecidochares utilis. The results showed that both CE and BT + CE significantly enhanced nutrient concentration and promoted the growth of A. adenophora. The aboveground biomass increased by 35.48 and 53.38% under non-parasitism and by 68.03% and 103.72% under the parasitism of P. utilis for these two treatments, respectively. In comparison to the control P. utilis-parasitized A. adenophora, the BT, CE, and BT + CE treatments significantly increased protective enzyme activity, jasmonic acid concentration, and secondary metabolites. Our study indicates that the recruitment of B. thuringiensis in the rhizosphere of A. adenophora can enhance its defense ability, while C. etunicatum improved both growth and defense ability. The interaction effects of these two microorganisms enhances the regulation of growth and defense ability of A. adenophora against P. utilis parasitism, providing insights into the feedback effects of beneficial microorganisms on the interactions between invasive plants and biological control. [ABSTRACT FROM AUTHOR]

Brown spot (BS) is caused by necrotrophs fungi Cochliobolus miyabeanus (C. miyabeanus) which affects rainfed and upland production in rice, resulting in significant losses in yield and grain quality. Here, we explored the meJA treatment that leads to rice resistance to BS. Fibrillins (FBNs) family are constituents of plastoglobules in chloroplast response to biotic and abiotic stress, many research revealed that OsFBN1 and OsFBN5 are not only associated with the rice against disease but also with the JA pathway. The function of FBN6 was only researched in the Arabidopsis. We revealed gene expression levels of OsFBN1, OsFBN5, OsFBN6 and the JA pathway synthesis first specific enzyme OsAOS2 following infection with C. miyabeanus, OsAOS2 gene expression showed great regulation after C. miyabeanus and meJA treatment, indicating JA pathway response to BS resistance in rice. Three FBN gene expressions showed different significantly regulated modes in C. miyabeanus and meJA treatment. The haplotype analysis results showed OsFBN1 and OsFBN5 the diverse Haps significant with BS infection score, and the OsFBN6 showed stronger significance (**** p < 0.0001). Hence, we constructed OsFBN6 overexpression lines, which showed more resistance to BS compared to the wild type, revealing OsFBN6 positively regulated rice resistance to BS. We developed OsFBN6 genetic markers by haplotype analysis from 130 rice varieties according to whole-genome sequencing results, haplotype analysis, and marker development to facilitate the screening of BS-resistant varieties in rice breeding. The Caps marker developed by Chr4_30690229 can be directly applied to the breeding application of screening rice BS-resistant varieties. [ABSTRACT FROM AUTHOR]

Plant nucleotide-binding leucine-rich repeat immune receptor genes (NLRs) play an important role in plant defenses against pathogens, pathogenic nematodes, and piercing–sucking herbivores. However, little is known about their functions in plant defenses against chewing herbivores. Here, we identified a plasma membrane-localized coiled-coil-type NLR protein, OsPik-2-like, whose transcript levels were induced by the infestation of rice leaf folder (LF, Cnaphalocrocis medinalis) larvae, and by treatment with mechanical wounding. Knocking out OsPik-2-like in rice increased the LF-induced levels of jasmonic acid (JA) and jasmonoyl–isoleucine (JA-Ile), the activity of trypsin protease inhibitors (TrypPIs), and the basal levels of some flavonoids, which in turn decreased the performance of LF larvae. Moreover, knocking out OsPik-2-like reduced plant growth. These findings demonstrate that OsPik-2-like regulates the symbiosis between rice and LF by balancing plant growth and defense. [ABSTRACT FROM AUTHOR]

ABSTRACT Plant viruses rely on host factors for successful infection. Non‐specific lipid transfer proteins (nsLTPs) play critical roles in plant−pathogen interactions; however, their functions and underlying molecular mechanisms in viral infections remain largely unknown. Jasmonic acid (JA) is a crucial regulatory hormone in the process of plant resistance to viral infection. In this study, we screened and verified that StLTP6, a previously identified pro‐viral factor, interacts with the silencing suppressor triple gene block1 (TGB1) of potato virus S (PVS). The PVS TGB1 induces the expression of StLTP6, and both co‐localize in the cytoplasm. Furthermore, StLTP6 interacts with allene oxide cyclase and inhibits its accumulation, thereby suppressing JA synthesis and attenuating RNA silencing antiviral resistance. In summary, we elucidated the molecular mechanism by which PVS TGB1 interacts with StLTP6 to facilitate PVS infection. These findings broaden our understanding of the biological roles of nsLTPs and provide a new antiviral target for potato research. [ABSTRACT FROM AUTHOR]