Unveiling plant defense arsenal: metabolic strategies in Brassica oleracea during black rot disease.

Alterations in plant metabolism play a key role in the complex plant-pathogen interactions. However, there is still a lack of knowledge about the connection between changes in primary and specialized metabolism and the plant defense against diseases that impact crops. Thus, we aim to study the metabolic reprograming in Brassica oleracea plants upon infection by Xanthomonas campestris pv. campestris (Xcc). To accomplish this, we utilized a combination of untargeted and targeted metabolomics, through UPLC-Q-TOF-MS/MS and 1H-NMR, in two crop lines differing in resistance that were evaluated at two- and four-week intervals following inoculation (T1 and T2, respectively). Besides, to depict the physiological status of the plant during infection, enzymatic activities related to the carbohydrate pathway and oxidative stress were studied. Our results revealed different temporal dynamics in the responses of the susceptible vs. resistant crops lines. Resistant B. oleracea line suppresses carbohydrate metabolism contributing to limit nutrient supplies to the bacterium and prioritizes the induction of defensive compounds such as indolic glucosinolates, salicylic acid, phenylpropanoids and phytoalexins precursors at early infection stages. In contrast, the susceptible line invests in carbohydrate metabolism, including enzymatic activities related to the hexoses turnover, and activates defense signaling related to reactive oxygen species. Thus, each line triggers a different metabolic strategy that will affect how the plant overcomes the disease in terms of resistance and growth. This work provides first insights of a fine-tuned metabolic regulation during Xcc infection in B. oleracea that will contribute to develop new strategies for plant disease management.

Spectral Reflectance Indexes Reveal Differences in the Physiological Status of Brassica oleracea with Contrasting Glucosinolate Content under Biotic Stress.

Brassica species produce glucosinolates, a specific group of secondary metabolites present in the Brassicaceae family with antibacterial and antifungal properties. The employment of improved varieties for specific glucosinolates would reduce the production losses caused by pathogen attack. However, the consequences of the increment in these secondary metabolites in the plant are unknown. In this work, we utilized reflectance indexes to test how the physiological status of Brasica oleracea plants changes depending on their constitutive content of glucosinolates under nonstressful conditions and under the attack of the bacteria Xanthomonas campestris pv. campestris and the fungus Sclerotinia sclerotiorum. The modification in the content of glucosinolates had consequences in the resistance to both necrotrophic pathogens, and in several physiological aspects of the plants. By increasing the content in sinigrin and glucobrassicin, plants decrease photosynthesis efficiency (PR531, FvFm), biomass production (CHL-NDVI, SR), pigment content (SIPI, NPQI, RE), and senescence (YI) and increase their water content (WI900). These variables may have a negative impact in the productivity of crops in an agricultural environment. However, when plants are subjected to the attack of both necrotrophic pathogens, an increment of sinigrin and glucobrassicin confers an adaptative advantage to the plants, which compensates for the decay of physiological parameters.

The growth-immunity tradeoff in Brassica oleracea-Xanthomonas campestris pv. campestris pathosystem.

Plant responses against pathogens are influenced by growth immunity tradeoff, which ensure the best use of limited resources. We study how the immobilization of carbon resources and the induction of defensive responses (glucosinolates, phenolic compounds, stomatal closure) can influence the biomass of two Brassica oleracea lines, differing in their resistance, after infection with Xanthomonas campestris pv. campestris. Potentially, the growth immunity tradeoff can be influenced by the activation of all these processes. However, on the contrary of which is normally stated, our results suggest that the loss of biomass caused by pathogen infection is mainly due to the differential accumulation of starch and the immobilization of sugars rather than the reallocation of resources to synthesize secondary metabolites. Moreover, resistance may be related to the effectiveness of the tradeoff, since the resistant line immobilizes resources more efficiently than the susceptible one. Both inbred lines show a different phytohormones profile, which support the hypothesis that they are employing different strategies to defend themselves against the pathogen. This study emphasizes the key role of the primary metabolism in the defence strategies of plants against pathogens.

New Vegetable Brassica Foods: A Promising Source of Bioactive Compounds.

Brassica rapa is grown in northwestern Spain to obtain turnip greens. The tops of the same plants (flower stems with buds) are cut and sell as turnip tops, increasing the value of the crop. This practice could be extended to other brassicas. The objectives of this work are to study the phytochemical potential of tops of coles (Brassica oleracea) and leaf rape (Brassica napus) compared to turnip tops and to compare tops of different coles (cabbage, kale, tronchuda cabbage), which differ in their morphology and use. We evaluated the content of glucosinolates and phenolic compounds and the antioxidant capacity in leaves and tops of the three species. We found that tops had higher amount of glucosinolates than leaves. Phenolic content and antioxidant capacity followed the opposite trend. Therefore, consumption of leaves and tops are complementary, since both type of organs are enriched with different types of compound. Local varieties of kale, curly kale, cabbage and curly leave cabbage are interesting because of their GSLs and phenolic content and antioxidant capacity in both leaves and tops. From the human health perspective, tops of coles and leaf rape are interesting as new crops to include in the diet.

Trichoderma hamatum Increases Productivity, Glucosinolate Content and Antioxidant Potential of Different Leafy Brassica Vegetables.

Brassica crops include important vegetables known as "superfoods" due to the content of phytochemicals of great interest to human health, such as glucosinolates (GSLs) and antioxidant compounds. On the other hand, Trichoderma is a genus of filamentous fungi that includes several species described as biostimulants and/or biological control agents in agriculture. In a previous work, an endophytic strain of Trichoderma hamatum was isolated from kale roots (Brassica oleracea var. acephala), describing its ability to induce systemic resistance in its host plant. In the present work, some of the main leafy Brassica crops (kale, cabbage, leaf rape and turnip greens) have been root-inoculated with T. hamatum, having the aim to verify the possible capacity of the fungus as a biostimulant in productivity as well as the foliar content of GSLs and its antioxidant potential, in order to improve these "superfoods". The results reported, for the first time, an increase in the productivity of kale (55%), cabbage (36%) and turnip greens (46%) by T. hamatum root inoculation. Furthermore, fungal inoculation reported a significant increase in the content of total GSLs in cabbage and turnip greens, mainly of the GSLs sinigrin and gluconapin, respectively, along with an increase in their antioxidant capacity. Therefore, T. hamatum could be a good agricultural biostimulant in leafy Brassica crops, increasing the content of GSLs and antioxidant potential of great food and health interest.

Transcriptomic Reprograming of Xanthomonas campestris pv. campestris after Treatment with Hydrolytic Products Derived from Glucosinolates.

The bacterium Xanthomonas campestris pv. campestris (Xcc) causes black rot disease in Brassica crops. Glucosinolates are known to be part of the defence system of Brassica crops against Xcc infection. They are activated upon pathogen attack by myrosinase enzymes. Their hydrolytic products (GHPs) inhibit the growth of Xcc in vitro. However, the mechanisms underlying this inhibition and the way Xcc can overcome it are not well understood. We studied the transcriptomic reprogramming of Xcc after being supplemented with two chemically different GHPs, one aliphatic isothiocyanate (allyl-ITC) and one indole (indol-3-carbinol), by RNA-seq. Based on our results, the arrest in Xcc growth is related to the need to stop cell division to repair damaged DNA and cell envelope components. Otherwise, GHPs modify energy metabolism by inhibiting aerobic respiration and increasing the synthesis of glycogen. Xcc induces detoxification mechanisms such as the antioxidant defence system and the multidrug efflux system to cope with the toxic effects driven by GHPs. This is the first time that the transcriptomic reprogramming of a plant pathogenic bacterium treated with GHPs has been studied. This information will allow a better understanding of the interaction of a plant pathogen mediated by GSLs.

Sclerotinia sclerotiorum Response to Long Exposure to Glucosinolate Hydrolysis Products by Transcriptomic Approach.

White mold disease, caused by the necrotrophic fungus Sclerotinia sclerotiorum, affects Brassica crops. Brassica crops produce a broad array of compounds, such as glucosinolates, which contribute to the defense against pathogens. From their hydrolysis, several products arise that have antimicrobial activity (GHPs) whose toxicity is structure dependent. S. sclerotiorum may overcome the toxic effect of moderate GHP concentrations after prolonged exposure to their action. Our objective was to identify the molecular mechanism underlying S. sclerotiorum response to long exposure to two chemically diverse GHPs: aliphatic GHP allyl-isothiocyanate (AITC) and indole GHP indol-3-carbinol (I3C). We found that the transcriptomic response is dependent on the type of GHP and on their initial target, involving cell membranes in the case of AITC or DNA in the case of I3C. Response mechanisms include the reorganization of chromatin, mediated by histone chaperones hip4 and cia1, ribosome synthesis controlled by the kinase-phosphatase pair aps1-ppn1, catabolism of proteins, ergosterol synthesis, and induction of detoxification systems. These mechanisms probably help S. sclerotiorum to grow and survive in an environment where GHPs are constantly produced by Brassica plants upon glucosinolate breakdown. IMPORTANCEBrassica species, including important vegetable crops, such as cabbage, cauliflower, or broccoli, or oil crops, such as rapeseed, produce specific chemical compounds useful to protect them against pests and pathogens. One of the most destructive Brassica diseases in temperate areas around the world is Sclerotinia stem rot, caused by the fungus Sclerotinia sclerotiorum. This is a generalist pathogen that causes disease over more than 400 plant species, being a serious threat to economically important crops worldwide, including potato, bean, soybean, and sunflower, among many others. Understanding the mechanisms utilized by pathogens to overcome specific plant defensive compounds can be useful to increase plant resistance. Our study demonstrated that Sclerotinia shows different adaptation mechanisms, including detoxification systems, to grow and survive when plant protective compounds are present.

Fine mapping identifies NAD-ME1 as a candidate underlying a major locus controlling temporal variation in primary and specialized metabolism in Arabidopsis.

Plant metabolism is modulated by a complex interplay between internal signals and external cues. A major goal of all quantitative metabolomic studies is to clone the underlying genes to understand the mechanistic basis of this variation. Using fine-scale genetic mapping, in this work we report the identification and initial characterization of NAD-DEPENDENT MALIC ENZYME 1 (NAD-ME1) as the candidate gene underlying the pleiotropic network Met.II.15 quantitative trait locus controlling variation in plant metabolism and circadian clock outputs in the Bay × Sha Arabidopsis population. Transcript abundance and promoter analysis in NAD-ME1Bay-0 and NAD-ME1Sha alleles confirmed allele-specific expression that appears to be due a polymorphism disrupting a putative circadian cis-element binding site. Analysis of transfer DNA insertion lines and heterogeneous inbred families showed that transcript variation of the NAD-ME1 gene led to temporal shifts of tricarboxylic acid cycle intermediates, glucosinolate (GSL) accumulation, and altered regulation of several GSL biosynthesis pathway genes. Untargeted metabolomic analyses revealed complex regulatory networks of NAD-ME1 dependent upon the daytime. The mutant led to shifts in plant primary metabolites, cell wall components, isoprenoids, fatty acids, and plant immunity phytochemicals, among others. Our findings suggest that NAD-ME1 may act as a key gene to coordinate plant primary and secondary metabolism in a time-dependent manner.

Apparent inhibition of induced plant volatiles by a fungal pathogen prevents airborne communication between potato plants.

Plant communication in response to insect herbivory has been increasingly studied, whereas that involving pathogen attack has received much less attention. We tested for communication between potato (Solanum tuberosum) plants in response to leaf infection by the fungal pathogen Sclerotinia sclerotiorum. To this end, we measured the total amount and composition of volatile organic compounds (VOCs) produced by control and infected emitter plants, as well as tested for induced resistance of receiver plants exposed to VOCs from emitters. We further tested for changes in the expression of defensive genes due to pathogen infection. Fungal infection did not significantly affect the total amount or composition of VOCs produced by emitter plants. Correspondingly, we found no evidence of higher resistance to the pathogen in receiver plants exposed to VOCs from infected emitters relative to control emitters. Molecular analyses indicated that pathogen infection drove a down-regulation of genes coding for VOC precursors, potentially explaining the absence of pathogen effects on VOC emissions and thus of communication. Overall, these results indicate no evidence of airborne communication between potato plants in response to fungal infection and point at pathogen inhibition of VOC emissions as a likely explanation for this result.

Brassica oleracea var. acephala (kale) improvement by biological activity of root endophytic fungi.

Brassica oleracea var. acephala (kale) is a cruciferous vegetable widely cultivated for its leaves and flower buds in Atlantic Europe and the Mediterranean area, being a food of great interest as a "superfood" today. Little has been studied about the diversity of endophytic fungi in the Brassica genus, and there are no studies regarding kale. In this study, we made a survey of the diversity of endophytic fungi present in the roots of six different Galician kale local populations. In addition, we investigated whether the presence of endophytes in the roots was beneficial to the plants in terms of growth, cold tolerance, or resistance to bacteria and insects. The fungal isolates obtained belonged to 33 different taxa. Among those, a Fusarium sp. and Pleosporales sp. A between Setophoma and Edenia (called as Setophoma/Edenia) were present in many plants of all five local populations, being possible components of a core kale microbiome. For the first time, several interactions between endophytic fungus and Brassica plants are described and is proved how different interactions are beneficial for the plant. Fusarium sp. and Pleosporales sp. B close to Pyrenophora (called as Pyrenophora) promoted plant growth and increased cold tolerance. On the other hand, isolates of Trichoderma sp., Pleosporales sp. C close to Phialocephala (called as Phialocephala), Fusarium sp., Curvularia sp., Setophoma/Edenia and Acrocalymma sp. were able to activate plant systemic resistance against the bacterial pathogen Xanthomonas campestris. We also observed that Fusarium sp., Curvularia sp. and Setophoma/Edenia confered resistance against Mamestra brassicae larvae.

Glucosinolate-Degradation Products as Co-Adjuvant Therapy on Prostate Cancer in Vitro.

Glucosinolate-degradation products (GS-degradation products) are believed to be responsible for the anticancer effects of cruciferous vegetables. Furthermore, they could improve the efficacy and reduce side-effects of chemotherapy. The aim of the present study was to determine the cytotoxic effects of GS-degradation products on androgen-insensitive human prostate cancer (AIPC) PC-3 and DU 145 cells and investigate their ability to sensitize such cells to chemotherapeutic drug Docetaxel (DOCE). Cells were cultured under growing concentrations of allyl-isothiocyanate (AITC), sulforaphane (SFN), 4-pentenyl-isothiocyanate (4PI), iberin (IB), indole-3-carbinol (I3C), or phenethyl-isothiocyanate (PEITC) in absence or presence of DOCE. The anti-tumor effects of these compounds were analyzed using the trypan blue exclusion, apoptosis, invasion and RT-qPCR assays and confocal microscopy. We observed that AITC, SFN, IB, and/or PEITC induced a dose- and time-dependent cytotoxic effect on PC-3 and DU 145 cells, which was mediated, at least, by apoptosis and cell cycle arrest. Likewise, we showed that these GS-degradation products sensitized both cell lines to DOCE by synergic mechanisms. Taken together, our results indicate that GS-degradation products can be promising compounds as co-adjuvant therapy in prostate cancer.

Calcium-signaling proteins mediate the plant transcriptomic response during a well-established Xanthomonas campestris pv. campestris infection.

The plant immune system is divided into two branches; one branch is based on the recognition of pathogen-associated molecular patterns (PAMP-triggered immunity), and the other relies on pathogenic effector detection (effector-triggered immunity). Despite each branch being involved in different complex mechanisms, both lead to transcription reprogramming and, thus, changes in plant metabolism. To study the defense mechanisms involved in the Brassica oleracea-Xanthomonas campestris pv. campestris (Xcc) interaction, we analyzed the plant transcriptome dynamics at 3 and 12 days postinoculation (dpi) by using massive analysis of 3'-cDNA ends. We identified more induced than repressed transcripts at both 3 and 12 dpi, although the response was greater at 12 dpi. Changes in the expression of genes related to the early infection stages were only detected at 12 dpi, suggesting that the timing of triggered defenses is crucial to plant survival. qPCR analyses in susceptible and resistant plants allowed us to highlight the potential role of two calcium-signaling proteins, CBP60g and SARD1, in the resistance against Xcc. This role was subsequently confirmed using Arabidopsis knockout mutants.

Role of Major Glucosinolates in the Defense of Kale Against Sclerotinia sclerotiorum and Xanthomonas campestris pv. campestris.

Glucosinolates (GSLs) are secondary metabolites present in Brassicaceae species implicated in their defense against plant pathogens. When a pathogen causes tissue damage, the enzyme myrosinase hydrolyzes GSLs into diverse products that exhibit antimicrobial activity against a wide range of bacteria and fungi in vitro. It was demonstrated that modulation of GSL content in vivo affects plant resistance to infection by pathogens in Arabidopsis. However, the roles of specific metabolites and how they interact with pathogens are poorly understood in Brassica crops. We previously developed a set of populations of Brassica oleracea var. acephala L. (kale) differing in content of three GSLs: the aliphatics sinigrin (2-propenyl [SIN]) and glucoiberin (3-methylsulphinylpropyl [GIB]) and the indolic glucobrassicin (3-indolylmethyl [GBS]). These populations can be used to study the effects of major GSLs in kale, with the advantage that genotypes within each selection have the same genetic background. This research aimed to explore the role of SIN, GIB, and GBS in the defense of kale against the necrotrophic fungus Sclerotinia sclerotiorum and the bacterium Xanthomonas campestris pv. campestris. Results showed that increasing the amount of a particular GSL did not always result in disease resistance. The effects of GSLs were apparently dependent on the pathogen and the type of GSL. Thus, the aliphatic SIN was inhibitory to infection by S. sclerotiorum and the indolic GBS was inhibitory to infection by X. campestris pv. campestris. Other factors, including the quantity and proportion of other metabolites modified during the pathogen infection process, could also modulate the degree of inhibition to the pathogen.

Dissecting quantitative resistance to Xanthomonas campestris pv. campestris in leaves of Brassica oleracea by QTL analysis.

Black rot, caused by the bacterium Xanthomonas campestris pv. campestris (Xcc), produces important economic losses in crops of Brassica oleracea worldwide. Resistance to race 1, the most virulent and widespread in B. oleracea, is under quantitative control. Knowledge about the genetics of this resistance would help in designing strategies to control initial stages of invasion and development of the disease. QTL analysis of the resistance in the BolTBDH mapping population was performed. Resistance was measured with five traits related to initial stages of the invasion, success of infection and spread of the pathogen. Four single-trait QTLs of resistance were found, from which one represent novel variation. After performing multi-trait QTL, we concluded that spread of Xcc is related to the size of the leaf. Individuals from the mapping population follow two different strategies to cope with the spread of the disease: reducing lesion size or maintain more area of the leaf photosynthetically active, being more tolerant to Xcc invasion. Mechanisms underlying variation for resistance may be related to different aspects of plant immunity, including the synthesis of glucosinolates and phenolics.

Brassica glucosinolate rhythmicity in response to light-dark entrainment cycles is cultivar-dependent.

Coordination of plant circadian rhythms with the external environment provides growth and reproductive advantages to plants as well as enhanced resistance to insects and pathogens. Since glucosinolates (GLSs) play a major role as plant defensive compounds and could affect the palatability and health value of edible crops, the aim of this study was to investigate the species-specific patterns in circadian rhythmicity of these plant phytochemicals. Five different GLS-containing cultivars, from three Brassica crop species were studied. Plants were entrained to light-dark cycles (LD) for five weeks prior to release them into continuous light (LL). GLSs levels were monitored during five consecutive days (two days at LD conditions and three days at LL). The remaining plants were re-entrained to LD cycles (Re-LD plants) and GLS levels were studied as stated before during two consecutive days. Results showed that the period and amplitude of GLSs circadian outputs were cultivar-dependent. In addition, we assessed that the plant endogenous clock can be re-entrained for GLSs accumulation after a period of free-running conditions. Together, these data suggests that Brassica cultivars keep track the time of the day to coordinate their defenses. The demonstration of the cultivar-specific circadian effect on the GLSs levels in plants of different Brassica cultivars have the potential to identify new targets for improving cultivar phytochemicals using temporally informed approaches. In addition, provides an exceptional model to study the complexity of signal integration in plants.

Effect of Temperature Stress on Antioxidant Defenses in Brassica oleracea.

Brassica oleracea crops are exposed to seasonal changes in temperature because of their biennial life cycle. Extreme temperatures (cold and heat) affect the photosynthetic activity and the yield of cabbage (B. oleracea capitata group) and kale (B. oleracea acephala group). We studied the relationship among antioxidant defenses, photosynthesis, and yield under extreme temperatures in both crops. Under these conditions, the plants increase the antioxidant defenses, responding to an increment in reactive oxygen species (ROS). The accumulation of ROS in chloroplasts decreases the chlorophyll content and provokes photoinhibition that leads to a low fixation of CO2 and loss of dry weight. Low temperatures especially increase the antioxidant defenses and decrease the chlorophyll content compared to the heat conditions. However, dry weight losses are higher when plants are grown under heat than under cold conditions, probably because of the inactivation of Rubisco and/or the associated enzymes. Both crops were more resilient to cold than to heat temperatures, the capitata group being more resistant.

Endogenous Circadian Rhythms in Polyphenolic Composition Induce Changes in Antioxidant Properties in Brassica Cultivars.

There is increasing evidence that the circadian clock is a significant driver of plant phytochemicals. However, little is known about the clock effect on antioxidant metabolites in edible crops. Thus, the aim of the present investigation was to study whether the antioxidant potential of Brassica cultivars is under circadian regulation and its relationship with polyphenol content. To accomplish that we entrain plants of four Brassica cultivars to light-dark cycles prior to release into continuous light. The antioxidant activity and phenolic content was monitored at four time points of the day during four consecutive days: 2 days under light-dark conditions followed by 2 days under continuous light. Results showed daily oscillation of antioxidant activity. In addition, those variations were related with endogenous circadian rhythms in polyphenolics and exhibit a species-specific pattern. Considered together, we determined that Brassica cultivars have an optimal time during a single day with increased levels of health phytochemicals.

Modification of Leaf Glucosinolate Contents in Brassica oleracea by Divergent Selection and Effect on Expression of Genes Controlling Glucosinolate Pathway.

Modification of the content of secondary metabolites opens the possibility of obtaining vegetables enriched in these compounds related to plant defense and human health. We report the first results of a divergent selection for glucosinolate (GSL) content of the three major GSL in leaves: sinigrin (SIN), glucoiberin (GIB), and glucobrassicin (GBS) in order to develop six kale genotypes (Brassica oleracea var. acephala) with high (HSIN, HIGIB, HGBS) and low (LSIN, LGIB, LGBS) content. The aims were to determine if the three divergent selections were successful in leaves, how each divergent selection affected the content of the same GSLs in flower buds and seeds and to determine which genes would be involved in the modification of the content of the three GSL studied. The content of SIN and GIB after three cycles of divergent selection increased 52.5% and 77.68%, and decreased 51.9% and 45.33%, respectively. The divergent selection for GBS content was only successful and significant for decreasing the concentration, with a reduction of 39.04%. Mass selection is an efficient way of modifying the concentration of individual GSLs. Divergent selections realized in leaves had a side effect in the GSL contents of flower buds and seeds due to the novo synthesis in these organs and/or translocation from leaves. The results obtained suggest that modification in the SIN and GIB concentration by selection is related to the GSL-ALK locus. We suggest that this locus could be related with the indirect response found in the GBS concentration. Meantime, variations in the CYP81F2 gene expression could be the responsible of the variations in GBS content. The genotypes obtained in this study can be used as valuable materials for undertaking basic studies about the biological effects of the major GSLs present in kales.

Effects of Brassicaceae Isothiocyanates on Prostate Cancer.

Despite the major progress made in the field of cancer biology, cancer is still one of the leading causes of mortality, and prostate cancer (PCa) is one of the most encountered malignancies among men. The effective management of this disease requires developing better anticancer agents with greater efficacy and fewer side effects. Nature is a large source for the development of chemotherapeutic agents, with more than 50% of current anticancer drugs being of natural origin. Isothiocyanates (ITCs) are degradation products from glucosinolates that are present in members of the family Brassicaceae. Although they are known for a variety of therapeutic effects, including antioxidant, immunostimulatory, anti-inflammatory, antiviral and antibacterial properties, nowadays, cell line and animal studies have additionally indicated the chemopreventive action without causing toxic side effects of ITCs. In this way, they can induce cell cycle arrest, activate apoptosis pathways, increase the sensitivity of resistant PCa to available chemodrugs, modulate epigenetic changes and downregulate activated signaling pathways, resulting in the inhibition of cell proliferation, progression and invasion-metastasis. The present review summarizes the chemopreventive role of ITCs with a particular emphasis on specific molecular targets and epigenetic alterations in in vitro and in vivo cancer animal models.

Omics Approach to Identify Factors Involved in Brassica Disease Resistance.

Understanding plant's defense mechanisms and their response to biotic stresses is of fundamental meaning for the development of resistant crop varieties and more productive agriculture. The Brassica genus involves a large variety of economically important species and cultivars used as vegetable source, oilseeds, forage and ornamental. Damage caused by pathogens attack affects negatively various aspects of plant growth, development, and crop productivity. Over the last few decades, advances in plant physiology, genetics, and molecular biology have greatly improved our understanding of plant responses to biotic stress conditions. In this regard, various 'omics' technologies enable qualitative and quantitative monitoring of the abundance of various biological molecules in a high-throughput manner, and thus allow determination of their variation between different biological states on a genomic scale. In this review, we have described advances in 'omic' tools (genomics, transcriptomics, proteomics and metabolomics) in the view of conventional and modern approaches being used to elucidate the molecular mechanisms that underlie Brassica disease resistance.