BjuA03.BNT1 plays a positive role in resistance to clubroot disease in resynthesized Brassica juncea L.

Clubroot has become a major obstacle in rapeseed production. Breeding varieties resistant to clubroot is the most effective method for disease management. However, the clubroot-resistant germplasm of rapeseed remains limited. To tackle this challenge, we synthesized the clubroot-resistant mustard, CT19, via distant hybridization, and subsequently an F2 segregating population was created by intercrossing CT19 with a clubroot-susceptible germplasm CS15. A major-effect clubroot resistance QTL qCRa3-1 on chromosome A03 was identified through QTL scanning. Transcriptome analyses of CT19 and CS15 revealed that the mechanisms conferring resistance to Plasmodiophora brassica likely involved the regulation of flavonoid metabolism, fatty acid metabolism, and sulfur metabolism. By combining the results from transcriptome, QTL mapping, and gene sequencing, a candidate gene BjuA03.BNT1, encoding NLR (nucleotide-binding domain leucine-rich repeat-containing receptors) protein, was obtained. Intriguingly, comparing with CT19, a base T insertion was discovered in the BjuA03.BNT1 gene's coding sequence in CS15, resulting an alteration within the LRR conserved domain. Overexpression of BjuA03.BNT1 from CT19 notably enhanced the resistance to clubroot in Arabidopsis. Our investigations revealed that BjuA03.BNT1 regulated the resistance to clubroot by modulating fatty acid synthesis and the structure of cell wall. These results are highly relevant for molecular breeding to improve clubroot resistance in rapeseed.

Effectiveness of Brassica juncea (Mustard) Plaster on Reduction of Knee Pain and Inability among Geriatrics with Osteoarthritis.

Pre-experimental one-group pretest posttest research design was adopted to investigate the effectiveness of Brassica juncea (mustard) plaster on reduction of knee pain and inability among 60 geriatrics with osteoarthritis. The inability was assessed using the Western Ontario McMaster University (WOMAC) Index, which includes 24 parameters under three major headings: joint pain, joint stiffness, and difficulty in performing daily activities, and the severity of pain level was assessed using a numerical pain rating scale. Mustard plaster is applied against the knee for 15 minutes once a day for seven days. On day 8, study participants were re-assessed using the WOMAC Osteoarthritis Index in the interventional group. The pretest mean score of pain was 77.80 ± 5.65, and the posttest mean score was 38.88 ± 11.76. The mean difference score was 38.92. The calculated paired 't' test value of t = 24.428 was statistically significant at P < 0.001 level.

The non-canonically organized members of MIR395 gene family in Brassica juncea are associated with developmentally regulated, sulfate-stress responsive bidirectional promoters that exhibit orientation-dependent differential transcriptional activity.

Several MICRORNA genes belonging to same family or different families are often found in homologous or non-homologous clusters. Among the various classes, head-to-head arranged genes form one of the largest categories of non-canonically organized genes. Such head-to-head arranged, non-canonically organized genes possibly share cis-regulatory region with the intergenic sequence having the potential to function as bi-directional promoter (BDP). The transcriptional regulation of head-to-head arranged genes, especially with bidirectional promoters, remains an enigma. In the past, bidirectional promoters have been characterized for a small set of protein-coding gene pairs in plants; however, to the best of our knowledge, no such study has been carried so far for MICRORNA genes. The present study thus functionally characterizes bidirectional promoters associated with members of MIR395 family, which is evolutionary conserved and is most frequently occurring cluster across plant kingdom. In Arabidopsis thaliana, the MIR395 gene family contains six members with two head-to-head arranged gene pairs- MIR395A-B and MIR395E-F. This organization was found to be conserved at seven loci for MIR395A-B, and eleven loci for MIR395E-F in five Brassica sps. Sequence analysis of the putative bidirectional promoters revealed variation in length, GC content and distribution of strict TATA-box. Comparatively higher level of conservation at both the ends of the bidirectional promoters, corresponding to ca. 250 bp upstream of 5'end of the respective MIRNA precursor, was observed. These conserved regions harbour several abiotic stress (nutrient, salt, drought) and hormone (ABA, ethylene) responsive cis-motifs. Functional characterization of putative bidirectional promoters associated with MIR395A-B and MIR395E-F from Arabidopsis and their respective orthologs from Brassica juncea (Bj_A08 MIR395A-B, Bj_B03 MIR395A-B, Bj_A07.1 MIR395E-F and Bj_A07.2 MIR395E-F) was carried out using a dual-reporter vector with ß-glucuronidase (GUS) and Green Fluorescent Protein (GFP). Analysis of transcriptional regulation of the two reporter genes - GUS and GFP during developmental stages confirmed their bidirectional nature. Orientation-dependent differential reporter activity indicated asymmetric nature of the promoters. Comparison of the reporter activity amongst orthologs, paralogs and homeologs revealed regulatory diversification, an outcome expected in polyploid genomes. Interestingly, reporter gene activities driven by selected bidirectional promoters were also observed in anther and siliques apart vegetative tissues indicating role of miR395 in anther and fruit development. Finally, we evaluated the activity of reporter genes driven under transcriptional regulation of bidirectional promoters under normal and sulfate-deprived conditions which revealed asymmetric inducibility under sulfate-starvation, in agreement with the known role of miR395 in sulfate homeostasis.

Transcriptional, biochemical, and histochemical response of resistant and susceptible cultivars of Brassica juncea against Albugo candida infection.

White rust disease caused by a biotrophic oomycete Albugo candida is one of the most serious impediments in realizing the production potential of Brassica juncea. Due to the obligate nature of the pathogen, R-gene-based resistance is unstable as the newer virulent races emerge quickly. For this, a deep understanding of the molecular basis of resistance is essential for developing durable resistant varieties. In this study, we selected one susceptible cultivar, 'Pusa Jaikisan' and its single R gene based resistant NIL, 'Pusa Jaikisan WRR as the source of understanding the defense mechanism in B. juncea against A. candida. Comparative histochemical analysis at 12 dpi showed higher callose deposition in the resistant cultivar than in the susceptible which hints towards its possible role in defense mechanism. Based on the biochemical markers observation, total protein was found to have a negative correlation with the resistance. The antioxidant enzymes (POX, CAT, and SOD) and non-enzymatic ROS scavenging compounds such as polyphenols and proline showed a positive correlation with the white rust resistance. Polyphenol Oxidase (PPO) total chlorophyll and total carotenoids were also found to be more abundant in the 'Pusa Jaikisan WRR'. Based on the heat map analysis, PAL was identified to be the comparatively most induced enzyme involved in the defense mechanism. The polyphenol oxidase, total chlorophyll and total carotenoids were also found to show higher activity in the 'Pusa Jaikisan WRR'. Furthermore, to study the defense response of 'Pusa Jaikisan WRR' compared to 'Pusa Jaikisan' against A. candida infection, the gene expression analyses of salicylic acid (SA)-marker PR protein genes (PR1 and PR2) and jasmonic acid (JA)-marker PR protein genes (PR3 and PR12) were done by qRT-PCR. Based on the results, PR2 emerged as the best possible gene for defense against A. candida followed by PR1. PR3 and PR12 also showed positive correlation with the disease resistance which may be due to the JA pathway acting complementary to the SA pathway in case of B. juncea-A. candida interaction. This provides evidence for the JA-SA hormonal crosstalk to be synergistic in case of the white rust resistance.

Molecular characterization and expression patterns of MTP genes under heavy metal stress in mustard (Brassica juncea L.).

Members of the Metal Tolerance Protein (MTP) family are critical in mediating the transport and tolerance of divalent metal cations. Despite their significance, the understanding of MTP genes in mustard (Brassica juncea) remains limited, especially regarding their response to heavy metal (HM) stress. In our study, we identified MTP gene sets in Brassica rapa (17 genes), Brassica nigra (18 genes), and B. juncea (33 genes) using the HMMER (Cation_efflux; PF01545) and BLAST analysis. For the 33 BjMTPs, a comprehensive bioinformatics analysis covering the physicochemical properties, phylogenetic relationships, conserved motifs, protein structures, collinearity, spatiotemporal RNA-seq expression, GO enrichment, and expression profiling under six HM stresses (Mn2+, Fe2+, Zn2+, Cd2+, Sb3+, and Pb2+) were carried out. According to the findings of physicochemical characteristics, phylogenetic tree, and collinearity, the allopolyploid B. juncea's MTP genes were inherited from its progenitors, B. rapa and B. nigra, with minimal gene loss during polyploidization. Members of the BjMTP family exhibited conserved motifs, promoter elements, and expression patterns across subgroups, consistent with the seven evolutionary branches (G1, G4-G9, and G12) of the MTPs. Further, spatiotemporal expression profiling under HM stresses successfully identified specific genes and crucial cis-regulatory elements associated with the response of BjMTPs to HM stresses. These findings may contribute to the genetic improvement of B. juncea for enhanced HM tolerance, facilitating the remediation of HM-contaminated areas.

Comparative metabolome variation in Brassica juncea different organs from two varieties as analyzed using SPME and GCMS techniques coupled to chemometrics.

Indian mustard (Brassica juncea; Brassicaceae) is an edible, oilseeds-yielding crop widely consumed as a food spice owing to its richness in nutrients with several health benefits. The current study aims to dissect the B. juncea metabolome heterogeneity among its different organs including leaf, stem, flower, and seed. Moreover, assessing the metabolome differences between two different varieties RH-725 and RH-761 grown at the same conditions. Gas chromatography-mass spectrometry (GC-MS) post-silylation was used to dissect the composition of nutrient metabolites coupled to multivariate data analysis. Variation in sulphur aglycones was measured using headspace-solid phase-microextraction HS-SPME coupled to GC-MS. A total of 101 nutrient metabolites were identified with the abundance of sugars represented by monosaccharides in all organs, except for seeds which were enriched in disaccharides (sucrose). α-Linolenic acid was detected as a marker fatty acid in leaf from RH-725 at 12.5 µg/mg. Malic acid was detected as a significant variant metabolite between the two varieties as detected in the leaf from the RH-725 variety at ca. 128.2 µg/mg compared to traces in RH-761. 7 Volatile sulphur compounds were detected at comparable levels in RH-725 and RH-761, with 3-butenyl isothiocyanate was the most abundant at 0.8-2 ng/mg.

Genetic diversification of allohexaploid Brassica hybrids (AABBCC) using a fertile octoploid with excessive C genome set (AABBCCCC).

MAIN CONCLUSION: Using octoploid somatic hybrids with excessive C genome sets, AABBCCCC, a diverse allohexaploid, AABBCC, was produced by C genome reduction through subsequent crossing with various AABB cultivars. Even when somatic hybrids are produced, the plants that are produced are rarely in themselves an innovative crop. In this study, we used somatic hybrids of Brassica juncea (AABB) and B. oleracea (CC) as model cases for the genetic diversification of the somatic hybrids. One cell of 'Akaoba Takana' (B. juncea) and two cells of 'Snow Crown' (B. oleracea) were fused to create several somatic hybrids with excessive C genomes, AABBCCCC. Using AABBCCCC somatic hybrids as mother plants and crossing with 'Akaoba Takana', the AABBCC progenies were generated. When these AABBCC plants were self-fertilized, and flow cytometric (FCM) analysis was performed on the next generations, differences in the relative amount of genome size variation were observed, depending on the different AABBCCCC parents used for AABBCC creation. Further self-progeny was obtained for AABBCC plants with a theoretical allohexaploid DNA index by FCM. However, as the DNA indices of the progeny populations varied between plants used and aneuploid individuals still occurred in the progeny populations, it was difficult to say that the allohexaploid genome was fully stabilized. Next, to obtain genetic diversification of the allohexaploid, different cultivars of B. juncea were crossed with AABBCCCC, resulting in diverse AABBCC plants. Genetic diversity can be further expanded by crossbreeding plants with different AABBCC genome sets. Although genetic stability is necessary to ensure in the later generations, the results obtained in this study show that the use of somatic hybrids with excess genomes is an effective strategy for creating innovative crops.

Using Quality by Design Tools to Study Gel Formulation from Brassica juncea Leaves and Conducting its In vitro, In vivo, Molecular Docking, and ADMET Analyses.

INTRODUCTION: This research aims to create a gel formulation of Brassica juncea leaf extract and assess its anti-inflammatory properties using an in silico study. The anti-inflamma-tory activity has been compared with Diclofenac molecules in PDB id: 4Z69. Further, the Ab-sorption, Distribution, Metabolism, Excretion, and Toxicity analysis has been performed to en-sure the therapeutic potential and safety of the drug development process. The Quality by De-sign tool has been applied to optimize formulation development. METHODS: The extracted gel is characterized by performing Fourier transformer infrared, zeta potential, particle size, Scanning Electron Microscope, and entrapment efficiency. Further, the formulation is evaluated by examining its viscosity, spreadability, and pH measurement. An In-vitro study of all nine extract suspensions was conducted to determine the drug contents at 276 nm. RESULTS: The optimized suspension has shown the maximum percentage of drug release (82%) in 10 hours of study. Animal study for anti-inflammatory activity was performed, and results of all five groups of animals compared the % inhibition of paw edema at three hours; gel (56.70 %), standard (47.86 %), and (39.72 %) were found. CONCLUSION: The research could conclude that the anti-inflammatory activity of gel formulation is high compared to extract, and a molecular docking study validates the anti-inflammatory ther-apeutic effects. ADMET analysis ensures the therapeutic effects and their safety.

GWAS for the identification of introgressed candidate genes of Sinapis alba with increased branching numbers in backcross lines of the allohexaploid Brassica.

Plant architecture is a crucial determinant of crop yield. The number of primary (PB) and secondary branches (SB) is particularly significant in shaping the architecture of Indian mustard. In this study, we analyzed a panel of 86 backcross introgression lines (BCILs) derived from the first stable allohexaploid Brassicas with 170 Sinapis alba genome-specific SSR markers to identify associated markers with higher PB and SB through association mapping. The structure analysis revealed three subpopulations, i.e., P1, P2, and P3, in the association panel containing a total of 11, 33, and 42 BCILs, respectively. We identified five novel SSR markers linked to higher PB and SB. Subsequently, we explored the 20 kb up- and downstream regions of these SSR markers to predict candidate genes for improved branching and annotated them through BLASTN. As a result, we predicted 47 complete genes within the 40 kb regions of all trait-linked markers, among which 35 were identified as candidate genes for higher PB and SB numbers in BCILs. These candidate genes were orthologous to ANT, RAMOSUS, RAX, MAX, MP, SEU, REV, etc., branching genes. The remaining 12 genes were annotated for additional roles using BLASTP with protein databases. This study identified five novel S. alba genome-specific SSR markers associated with increased PB and SB, as well as 35 candidate genes contributing to plant architecture through improved branching numbers. To the best of our knowledge, this is the first report of introgressive genes for higher branching numbers in B. juncea from S. alba.

Phytotoxic Strains of Fusarium commune Isolated from Truffles.

Most Fusarium species are known as endophytes and/or phytopathogens of higher plants and have a worldwide distribution. Recently, information discovered with molecular tools has been also published about the presence of these fungi in the microbiome of truffle fruiting bodies. In the present work, we isolated and identified three Fusarium strains from truffle fruiting bodies. All isolates were assigned to the same species, F. commune, and the strains were deposited in the All-Russian Collection of Microorganisms under accession numbers VKM F-5020, VKM F-5021, and VKM F-5022. To check the possible effects of the isolated strains on the plants, the isolates were used to infect sterile seedlings of Sarepta mustard (Brassica juncea L.). This model infection led to a moderate suppression of the photosynthetic apparatus activity and plant growth. Here, we present characteristics of the F. commune isolates: description of the conidial morphology, pigmentation, and composition of the mycelium fatty acids. Overall, this is the first description of the Fusarium cultures isolated from truffle fruiting bodies. Possible symbiosis of the F. commune strains with truffles and their involvement in the cooperative fatty acid production are proposed.

Exploring the role of 28-homobrassinolide in regulation of temperature induced clastogenic aberrations and sugar metabolism of Brassica juncea L.

The present research primarily focuses on Brassica juncea's physiological and cytological responses to low and high temperature stress at 4 °C and 44 °C respectively, along with elucidating the protective role of 28-Homobrassinolide (28-homoBL). Cytological investigations performed in floral buds of Brassica juncea L. under temperature (24, 4, 44 °C) stress conditions depict the presence of some abnormalities associated with cytomixis such as chromosome stickiness or agglutination, pycnotic nature of chromatin, irregularities in spindle formation, disoriented chromatins, and non-synchronous chromatin material condensation in Brassicaceae family that subsisted at diploid level (2n = 36). Spindle abnormalities produce various size pollen grains such as sporads micronuclei at some stages of microsporogenesis, polyads, triads, dyads that irrupted the productiveness of pollen grains. Furthermore, sugars play an imperative role in protecting plants under stress besides being energy sources. Therefore, the present study revealed accumulation of total soluble sugars (TSS), with 28-homoBL treatment which pinpoints protective role of 28-homoBL under temperature stress. Sugar profiling was done by using high-performance liquid chromatography (HPLC) which helped in analyzing different sugars both quantitatively and qualitatively under 28-homoBL and temperature stress conditions. The results indicate that the 28-homoBL treatment substantially enhances plant tolerance to heat stress, as evident by higher mitotic indices, fewer chromosomal abnormalities, and significantly more sugar accumulation. The findings of the study acknowledge the potential of 28-homoBL in inducing temperature stress tolerance in B. juncea along with improving the metabolic stability thereby implying application of 28-homoBL in crop strengthening under variable temperature conditions.

Combined effects of heatwaves and atmospheric CO2 levels on Brassica juncea phytoremediation.

Heatwaves, expected to become more frequent, pose a significant threat to plant biomass production. This experiment was designed to estimate heatwave influence on Brassica juncea phytoremediation when superimposed on different CO2 levels. A 7-day heatwave was generated during the species flowering stage. Heatwaves decreased all B. juncea dry weights. The lowest species dry weight was recorded when the heatwave was accompanied by 250 ppm CO2, in which the biomass significantly decreased by 40.0% relative to that of no heatwave under the same atmospheric CO2 conditions. Heatwave superposition with 250 ppm CO2 reduced the Cd content in B. juncea aerial parts by 28.1% relative to that of identical environmental conditions without heatwave, whereas the opposite result was observed under 550 ppm CO2 conditions. The heatwave caused oxidative damage to B. juncea under all CO2 conditions, as manifested by increased malondialdehyde levels in the plant shoots. With heatwave superposition, antioxidant enzyme activity was enhanced by exposure to 400 and 550 ppm CO2. Considering biomass yield generation and Cd uptake capacity, heatwave superposition decreased the B. juncea phytoremediation effects, and high atmospheric CO2 conditions could alleviate detrimental effects to a certain extent. This study uniquely examines the combined effects of heatwaves and varying CO2 levels on phytoremediation, providing microscopic insights into oxidative damage and enzyme activity, highlighting the potential for CO2 enrichment to mitigate heatwave impacts, and offering comprehensive analysis for future agricultural practices and environmental management.

Enhancement of the germination and growth of Panicum miliaceum and Brassica juncea in Cd- and Zn-contaminated soil inoculated with heavy-metal-tolerant Leifsonia sp. ZP3.

The addition of plant-growth-promoting bacteria (PGPB) to heavy-metal-contaminated soils can significantly improve plant growth and productivity. This study isolated heavy-metal-tolerant bacteria with growth-promoting traits and investigated their inoculation effects on the germination rates and growth of millet (Panicum miliaceum) and mustard (Brassica juncea) in Cd- and Zn-contaminated soil. Leifsonia sp. ZP3, which is resistant to Cd (0.5 mM) and Zn (1 mM), was isolated from forest soil. The ZP3 strain exhibited plant-growth-promoting activity, including indole-3-acetic acid production, phosphate solubilization, catalase activity, and 2,2-diphenyl-1-picrylhydrazyl radical scavenging. In soil contaminated with low concentrations of Cd (0.232 ± 0.006 mM) and Zn (6.376 ± 0.256 mM), ZP3 inoculation significantly increased the germination rates of millet and mustard 8.35- and 31.60-fold, respectively, compared to the non-inoculated control group, while the shoot and root lengths of millet increased 1.77- and 4.44-fold (p < 0.05). The chlorophyll content and seedling vigor index were also 4.40 and 18.78 times higher in the ZP3-treated group than in the control group (p < 0.05). The shoot length of mustard increased 1.89-fold, and the seedling vigor index improved 53.11-fold with the addition of ZP3 to the contaminated soil (p < 0.05). In soil contaminated with high concentrations of Cd and Zn (0.327 ± 0.016 and 8.448 ± 0.250 mM, respectively), ZP3 inoculation led to a 1.98-fold increase in the shoot length and a 2.07-fold improvement in the seedling vigor index compared to the control (p < 0.05). The heavy-metal-tolerant bacterium ZP3 isolated in this study thus represents a promising microbial resource for improving the efficiency of phytoremediation in Cd- and Zn-contaminated soil.

A chromosome-scale assembly of Brassica carinata (BBCC) accession HC20 containing resistance to multiple pathogens and an early generation assessment of introgressions into B. juncea (AABB).

Brassica carinata (BBCC) commonly referred to as Ethiopian mustard is a natural allotetraploid containing the genomes of Brassica nigra (BB) and Brassica oleracea (CC). It is an oilseed crop endemic to the northeastern regions of Africa. Although it is under limited cultivation, B. carinata is valuable as it is resistant/highly tolerant to most of the pathogens affecting widely cultivated Brassica species of the U's triangle. We report a chromosome-scale genome assembly of B. carinata accession HC20 using long-read Oxford Nanopore sequencing and Bionano optical maps. The assembly has a scaffold N50 of ~39.8 Mb and covers ~1.11 Gb of the genome. We compared the long-read genome assemblies of the U's triangle species and found extensive gene collinearity between the diploids and allopolyploids with no evidence of major gene losses. Therefore, B. juncea (AABB), B. napus (AACC), and B. carinata can be regarded as strict allopolyploids. We cataloged the nucleotide-binding and leucine-rich repeat immune receptor (NLR) repertoire of B. carinata and, identified 465 NLRs, and compared these with the NLRs in the other Brassica species. We investigated the extent and nature of early-generation genomic interactions between the constituent genomes of B. carinata and B. juncea in interspecific crosses between the two species. Besides the expected recombination between the constituent B genomes, extensive homoeologous exchanges were observed between the A and C genomes. Interspecific crosses, therefore, can be used for transferring disease resistance from B. carinata to B. juncea and broadening the genetic base of the two allotetraploid species.

Control of Sclerotinia sclerotiorum via an RNA interference (RNAi)-mediated targeting of SsPac1 and SsSmk1.

MAIN CONCLUSION: The study evaluates the potential of Spray-Induced Gene Silencing and Host-Induced Gene Silencing for sustainable crop protection against the broad-spectrum necrotrophic fungus Sclerotinia sclerotiorum. Sclerotinia sclerotiorum (Lib.) de Bary, an aggressive ascomycete fungus causes white rot or cottony rot on a broad range of crops including Brassica juncea. The lack of sustainable control measures has necessitated biotechnological interventions such as RNA interference (RNAi) for effective pathogen control. Here we adopted two RNAi-based strategies-Spray-Induced Gene Silencing (SIGS) and Host-Induced Gene Silencing (HIGS) to control S. sclerotiorum. SIGS was successful in controlling white rot on Nicotiana benthamiana and B. juncea by targeting SsPac1, a pH-responsive transcription factor and SsSmk1, a MAP kinase involved in fungal development and pathogenesis. Topical application of dsRNA targeting SsPac1 and SsSmk1 delayed infection initiation and progression on B. juncea. Further, altered hyphal morphology and reduced radial growth were also observed following dsRNA application. We also explored the impact of stable dsRNA expression in A. thaliana against S. sclerotiorum. In this report, we highlight the utility of RNAi as a biofungicide and a tool for preliminary functional genomics.

Bioformulation of Bacillus proteolyticus MITWPUB1 and its biosurfactant to control the growth of phytopathogen Sclerotium rolfsii for the crop Brassica juncea var local, as a sustainable approach.

Bacillus proteolyticus MITWPUB1 is a potential producer of biosurfactants (BSs), and the organism is also found to be a producer of plant growth promoting traits, such as hydrogen cyanide and indole acetic acid (IAA), and a solubilizer of phosphate. The BSs were reportedly a blend of two classes, namely glycolipids and lipopeptides, as found by thin layer chromatography and Fourier-transform infrared spectroscopy analysis. Furthermore, semi-targeted metabolite profiling via liquid chromatography mass spectroscopy revealed the presence of phospholipids, lipopeptides, polyamines, IAA derivatives, and carotenoids. The BS showed dose-dependent antagonistic activity against Sclerotium rolfsii; scanning electron microscopy showed the effects of the BS on S. rolfsii in terms of mycelial deformations and reduced branching patterns. In vitro studies showed that the application of B. proteolyticus MITWPUB1 and its biosurfactant to seeds of Brassica juncea var local enhanced the seed germination rate. However, sawdust-carrier-based bioformulation with B. proteolyticus MITWPUB1 and its BS showed increased growth parameters for B. juncea var L. This study highlights a unique bioformulation combination that controls the growth of the phytopathogen S. rolfsii and enhances the plant growth of B. juncea var L. Bacillus proteolyticus MITWPUB1 was also shown for the first time to be a prominent BS producer with the ability to control the growth of the phytopathogen S. rolfsii.

Deciphering variations, identification of marker-trait associations and candidate genes for seed oil content under terminal heat stress in Indian mustard (Brassica juncea L. Czern & Coss) germplasm stock.

This research paper investigates the variability in seed oil content (SOC) in Indian mustard (Brassica juncea L.) under terminal heat stress (THS) conditions. A genetic stock of 488 genotypes of B. juncea was evaluated over two years and grouped into five classes based on the reduction in oil content under THS compared to normal sown crop. Based on heat susceptibility index (HSI), a diverse panel of 96 genotypes was selected and evaluated under THS. Twenty-two heat-tolerant donor genotypes were identified, including introgression lines derived from B. tournefortii, B. carinata and Erucastrum cardaminoides. This study is the first to report on marker-trait associations for SOC in B. juncea under THS using a GWAS approach. Furthermore, candidate genes associated with abiotic stress tolerance and lipid metabolism were identified near the significant SNPs, emphasizing their role in SOC regulation under stress. Notable candidate genes include BjuA003240 (encoding for alcohol-forming fatty acyl-CoA reductase), BjuA003242 (involving in lipid biosynthesis), BjuA003244 (associated with mitochondrial functions and stress tolerance), and BjuA003245 (related to MYB transcription factors regulating lipid biosynthesis). This study provides valuable insights into the genetic basis of SOC variation under THS in B. juncea, highlighting potential breeding targets for improved heat stress resilience in Indian mustard cultivation. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-03985-w.

Zinc oxide nanoparticles and Klebsiella sp. SBP-8 alleviates chromium toxicity in Brassica juncea by regulation of antioxidant capacity, osmolyte production, nutritional content and reduction in chromium adsorption.

Heavy metals are one of the most damaging environmental toxins that hamper growth of plants. These noxious chemicals include lead (Pb), arsenic (As), nickel (Ni), cadmium (Cd) and chromium (Cr). Chromium is one of the toxic metal which induces various oxidative processes in plants. The emerging role of nanoparticles as pesticides, fertilizers and growth regulators have attracted the attention of various scientists. Current study was conducted to explore the potential of zinc oxide nanoparticles (ZnONPs) alone and in combination with plant growth promoting rhizobacteria (PGPR) Klebsiella sp. SBP-8 in Cr stress alleviation in Brassica juncea (L.). Chromium stress reduced shoot fresh weight (40%), root fresh weight (28%), shoot dry weight (28%) and root dry weight (34%) in B. juncea seedlings. Chromium stressed B. juncea plants showed enhanced levels of malondialdehyde (MDA), electrolyte leakage (EL), hydrogen peroxide (H2O2) and superoxide ion (O2• -). However, co-supplementation of ZnONPs and Klebsiella sp. SBP-8 escalated the activity of antioxidant enzymes i.e., superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) in B. juncea grown in normal and Cr-toxic soil. It is further proposed that combined treatment of ZnONPs and Klebsiella sp. SBP-8 may be useful for alleviation of other abiotic stresses in plants.

[Brassica juncea BjuWRKY71-1 accelerates flowering by regulating the expression of SOC1].

Brassica juncea (mustard) is a vegetable crop of Brassica, which is widely planted in China. The yield and quality of stem mustard are greatly influenced by the transition from vegetative growth to reproductive growth, i.e., flowering. The WRKY transcription factor family is ubiquitous in higher plants, and its members are involved in the regulation of many growth and development processes, including biological/abiotic stress responses and flowering regulation. WRKY71 is an important member of the WRKY family. However, its function and mechanism in mustard have not been reported. In this study, the BjuWRKY71-1 gene was cloned from B. juncea. Bioinformatics analysis and phylogenetic tree analysis showed that the protein encoded by BjuWRKY71-1 has a conserved WRKY domain, belonging to class Ⅱ WRKY protein, which is closely related to BraWRKY71-1 in Brassica rapa. The expression abundance of BjuWRKY71-1 in leaves and flowers was significantly higher than that in roots and stems, and the expression level increased gradually along with plant development. The result of subcellular localization showed that BjuWRKY71-1 protein was located in nucleus. The flowering time of overexpressing BjuWRKY71-1 Arabidopsis plants was significantly earlier than that of the wild type. Yeast two-hybrid assay and dual-luciferase reporter assay showed that BjuWRKY71-1 interacted with the promoter of the flowering integrator BjuSOC1 and promoted the expression of its downstream genes. In conclusion, BjuWRKY71-1 protein can directly target BjuSOC1 to promote plant flowering. This discovery may facilitate further clarifying the molecular mechanism of BjuWRKY71-1 in flowering time control, and creating new germplasm with bolting and flowering tolerance in mustard.

The Mechanism of the Anti-Obesity Effects of a Standardized Brassica juncea Extract in 3T3-L1 Preadipocytes and High-Fat Diet-Induced Obese C57BL/6J Mice.

Obesity is a global health concern. Recent research has suggested that the development of anti-obesity ingredients and functional foods should focus on natural products without side effects. We examined the effectiveness and underlying mechanisms of Brassica juncea extract (BJE) in combating obesity via experiments conducted in both in vitro and in vivo obesity models. In in vitro experiments conducted in a controlled environment, the application of BJE demonstrated the ability to suppress the accumulation of lipids induced by MDI in 3T3-L1 adipocytes. Additionally, it downregulated adipogenic-related proteins peroxisome proliferator-activated receptor-γ (PPAR-γ), CCAAT/enhancer-binding protein-α (C/EBP-α), adipocyte protein 2 (aP2), and lipid synthesis-related protein acetyl-CoA carboxylase (ACC). It also upregulated the heat generation protein peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) and fatty acid oxidation protein carnitine palmitoyltransferase-1 (CPT-1). The oral administration of BJE decreased body weight, alleviated liver damage, and inhibited the accumulation of lipids in mice with diet-induced obesity resulting from a high-fat diet. The inhibition of lipid accumulation by BJE in vivo was associated with a decreased expression of adipogenic and lipid synthesis proteins and an increased expression of heat generation and fatty acid oxidation proteins. BJE administration improved obesity by decreasing adipogenesis and activating heat generation and fatty acid oxidation in 3T3-L1 cells and in HFD-induced obese C57BL/6J mice. These results suggest that BJE shows potential as a natural method for preventing metabolic diseases associated with obesity.