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Polyploid plants often exhibit superior yield, stress resistance, and quality. In this study, homologous tetraploid wucai (Brassica campestris L.) was successfully obtained by spraying seedling growth points with colchicine. The morphological, cytological, and physiological characteristics of diploid and tetraploid wucai were analyzed, and transcriptomic sequencing was performed at three stages of development. Tetraploid seedings grew slowly but exhibited darker leaves, enlarged organs and cells, increased stomatal volume, decreased stomatal density, improved nutritional content, and enhanced photosynthesis. Differentially expressed genes (DEGs) identified in diploid and tetraploid plants at three stages of development were enriched in different pathways. Notably, DEGs identified in the tetraploid plants were specifically enriched in starch and sucrose metabolism, pentose and glucuronate interconversions, and ascorbate and aldarate metabolism. In addition, we found that the light green module was most relevant to ploidy, and DEGs in this module were significantly enriched in the glycolysis/gluconeogenesis and TCA cycle pathways. The differential expression of key glycolysis-associated genes at different developmental stages may be the driver of the observed differences between diploid and tetraploid wucai. This study lays a technical foundation for the development of polyploid wucai germplasm resources as well as the breeding of new varieties with improved quality, yield, and stress resistance. It also provides a good empirical reference for the genetic breeding of closely related Brassica species. [ABSTRACT FROM AUTHOR]

Salinity stress is a type of abiotic stress which negatively affects the signaling pathways and cellular compartments of plants. Melatonin (MT) has been found to be a bioactive compound that can mitigate these adverse effects, which makes it necessary to understand the function of MT and its role in salt stress. During this study, plants were treated exogenously with 100 µM of MT for 7 days and subjected to 200 mM of salt stress, and samples were collected after 1 and 7 days for different indicators and transcriptome analysis. The results showed that salt reduced chlorophyll contents and damaged the chloroplast structure, which was confirmed by the downregulation of key genes involved in the photosynthesis pathway after transcriptome analysis and qRT-PCR confirmation. Meanwhile, MT increased the chlorophyll contents, reduced the electrolyte leakage, and protected the chloroplast structure during salt stress by upregulating several photosynthesis pathway genes. MT also decreased the H2O2 level and increased the ascorbic acid contents and APX activity by upregulating genes involved in the ascorbic acid pathway during salt stress, as confirmed by the transcriptome and qRT-PCR analyses. Transcriptome profiling also showed that 321 and 441 DEGs were expressed after 1 and 7 days of treatment, respectively. The KEGG enrichment analysis showed that 76 DEGs were involved in the photosynthesis pathway, while 35 DEGs were involved in the ascorbic acid metabolism pathway, respectively. These results suggest that the exogenous application of MT in plants provides important insight into understanding MT-induced stress-responsive mechanisms and protecting Brassica campestris against salt stress by regulating the photosynthesis and ascorbic acid pathway genes. [ABSTRACT FROM AUTHOR]

The membrane-less organelles in cytoplasm that are presented as cytoplasmic foci were successively identified. Although multiple CCCH zinc-finger proteins have been found to be localized in cytoplasmic foci, the relationship between their specific localization and functions still needs further clarification. Here, we report that the heterologous expression of two Brassica campestris CCCH zinc-finger protein genes (BcMF30a and BcMF30c) in Arabidopsis thaliana can affect microgametogenesis by involving the formation of cytoplasmic foci. By monitoring the distribution of proteins and observing pollen phenotypes, we found that, when these two proteins were moderately expressed in pollen, they were mainly dispersed in the cytoplasm, and the pollen developed normally. However, high expression induced the assembly of cytoplasmic foci, leading to pollen abortion. These findings suggested that the continuous formation of BcMF30a/BcMF30c-associated cytoplasmic foci due to high expression was the inducement of male sterility. A co-localization analysis further showed that these two proteins can be recruited into two well-studied cytoplasmic foci, processing bodies (PBs), and stress granules (SGs), which were confirmed to function in mRNA metabolism. Together, our data suggested that BcMF30a and BcMF30c play component roles in the assembly of pollen cytoplasmic foci. Combined with our previous study on the homologous gene of BcMF30a/c in Arabidopsis, we concluded that the function of these homologous genes is conserved and that cytoplasmic foci containing BcMF30a/c may participate in the regulation of gene expression in pollen by regulating mRNA metabolism. [ABSTRACT FROM AUTHOR]

Simple Summary: The cabbage flea beetle (CFB; Phyllotreta striolata) is a significant pest of cruciferous vegetables in the world. CFB causes severe destruction of Chinese flowering cabbage (CFC; Brassica campestris L. ssp. chinensis var. utilis), a key leafy vegetable in South China. In practice, the current control approach of CFB is to kill adults by spraying chemical insecticides, but the control efficacy is not sufficient because the adults have a strong tolerance to insecticides; on the other hand, the larvae living in soil are not influenced by pesticides. It is urgent to develop sustainable technology to control CFB. Here, we provide a new technology to control larvae and adults through seed pelletization and stem–leaf spraying using Metarhizium anisopliae. This study provides new insights into the application of mycoinsecticides and the IPM of flea beetle. (1) Background: The cabbage flea beetle (CFB; Phyllotreta striolata) seriously damages the production of Chinese flowering cabbage (CFC; Brassica campestris L. ssp. chinensis var. utilis), which is a key leafy vegetable in South China. A large number of chemical insecticides have been sprayed to control this pest; as a result, residues and resistances are becoming an issue. It is necessary to develop biocontrol technologies to address this issue. (2) Methods: Fungal strains were selected based on bioactivity against CFB, and CFC seed pelletization with fungal conidia was subject to evaluation of control efficacy against CFB. The effective mixture of fungus and chemical insecticide was determined based on safety and joint toxicology tests. (3) Results: The screening of 103 strains from 14 genera identified the Metarhizium anisopliae strain MaGX19S02 (Ma) as the one with the highest virulence. The LC50s of Ma to CFB adult and second instar larvae on day 9 post-treatment were 3.04 × 106 and 27.2 × 106 spores/mL, respectively. In the pot test, the pelletization of CFC seeds with Ma conidia (50/25/12.5 mg in 1 g seed with 4 g fillers) demonstrated significant CFB mortalities (45–82%) 20 days after the larvae were introduced. In the field test, the seed pelletization achieved 57–81% control efficacy 14 days after sowing. Furthermore, the combination of Ma with chlorfenapyr (Chl) demonstrated a synergistic effect against CFB; based on this result, we prepared the mixture formulation of 20% Ma-Chl wettable powder (WP). The assessment of the effects of 20% Ma-Chl WP (500× diluent) against CFB revealed 93.33% mortality in the pot test and 61.3% control efficacy in the field test on day 7 post-treatment. (4) Conclusions: The findings demonstrate the potential of Ma to control CFB in the field. Seed pelletization with Ma conidia effectively controlled CFB larvae and protected CFC seedlings, wherein a mixture formulation of 20% Ma-Chl WP had substantial efficacy in controlling CFB adults. Our research provides new methods for CFB biocontrol. [ABSTRACT FROM AUTHOR]

Dehydration responsive element binding protein (DREB) is a significant transcription factor class known to be implicated in abiotic stresses. In this study, we systematically conducted a genome-wide identification and expression analysis of the DREB gene family, including gene structures, evolutionary relationships, chromosome distribution, conserved domains, and expression patterns. A total of 65 DREB family gene members were identified in Chinese cabbage (Brassica rapa L.) and were classified into five subgroups based on phylogenetic analysis. Through analysis of the conserved domains of BrDREB family genes, only one exon existed in the gene structure. Through the analysis of cis-acting elements, these genes were mainly involved in hormone regulation and adversity stress. In order to identify the function of BrDREB2B, overexpressed transgenic Arabidopsis was constructed. After different stress treatments, the germination rate, root growth, survival rate, and various plant physiological indicators were measured. The results showed that transgenic Arabidopsis thaliana plants overexpressing BrDREB2B exhibited enhanced tolerance to salt, heat and drought stresses. Taken together, our results are the first to report the BrDREB2B gene response to drought and heat stresses in Chinese cabbage and provide a basis for further studies to determine the function of BrDREBs in response to abiotic stresses. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The inheritance of anther orientation of 154 individuals from two B1 populations of Brassica rapa (syn. Brassica campestris) was evaluated under controlled conditions in a greenhouse. The anther orientation was evaluated visually at the time of fully open flowers. The observed extrorse:introrse ratios were 1: 1 in R-o-18 × (R-o-18 × RM29) population and 3: 1 in R-o-18 × (R-o-18 × R c-50) population. It was concluded that this trait is controlled by two duplicated pairs of genes (A1, A2) for extrorse anthers, either of which can produce extrorse anthers when a single dominant allele is present. Introrse anthers result when all alleles at both loci are recessive. [ABSTRACT FROM AUTHOR]

Background: Brassica campestris plant, a prominent member of Brassicaceae family, has documented therapeutic potential in the common cold, as an antibacterial, antiprotozoal, and to some extent an analgesic in folk medicine. Objectives: The present study aimed to determine the antinociceptive activity and analgesic potential of the ethanolic extract of the leaves of the Brassica campestris plant in rats. Materials and Methods: The antinociceptive potential and analgesic effects of the Brassica campestris leaves extract were evaluated by using the hot plate test and formalin analgesia method. The data were presented as mean ± standard error of the mean (M ± SEM). One-way analysis of variance [ANOVA] followed by Tukey's multiple comparison tests were performed for statistical analysis. P-value was considered significant at < 0.05. Results: The withdrawal latency period was noticed to be gradually and significantly prolonged after 400mg/kg oral administration of Brassica campestris leaves extract reaching a maximum of 12.73 ± 0.61 sec (p<0.05) as compared to control rats (6.13 ± 0.09 sec) in hot plate test. The antinociceptive behavior of experimental rats was also found quite significant in both phases of formalin-induced pain (61 and 81% respectively; p<0.05) when administered to plant extract at the dose of 400mg/kg body weight as compared to control animals (25 and 40% respectively). Conclusion: Brassica campestris leaves may contain pharmacologically active constituents associated with antinociceptive potential and analgesic effects in rats. The further characterization of those active moieties may be valuable for the treatment of pain and for designing a new analgesic strategy. [ABSTRACT FROM AUTHOR]

Purple flowering stalks and green flowering stalks of Brassica campestris are widely cultivated in the middle and upper reaches of the Yangtze River. Here, concentrations of the main health-promoting compounds and antioxidant capacity levels were characterized in different parts (leaves, peel, flesh, and inflorescences) of purple and green flowering stalks. There were significant differences in the concentrations of health-promoting compounds between the two variants; the concentrations of pigments, especially anthocyanidins, and gluconapin, were significantly higher in purple flowering stalks than in green flowering stalks, and the progoitrin content was significantly higher in green flowering stalks than in purple flowering stalks. The leaves were judged to be the most nutritional edible part because they had the highest concentrations of pigments, ascorbic acid, proanthocyanidins, flavonoids, and total phenolics. Antioxidant capacity was also highest in the leaves, and it was positively correlated with the concentration of health-promoting compounds. Purple flowering stalks and green flowering stalks were found to be rich in health-promoting compounds, especially glucosinolates. Overall, our findings indicate that consumption of the leaves and peel would provide the most health benefits. Some suggestions are provided regarding the processing and utilization of these edible components. [ABSTRACT FROM AUTHOR]

The availability of a high-quality genome sequence of Brassica campestris ssp. chinensis NHCC001 has paved the way for deep mining of genome data. We used the B. campestris NHCC001 draft genome to develop a comprehensive database, known as the non-heading Chinese cabbage database, which provides access to the B. campestris NHCC001 genome data. The database provides 127,347 SSR, from which 382,041 pairs of primers were designed. NHCCDB contains information on 105,360 genes, which were further classified into 63 transcription factor families. Furthermore, NHCCDB provides eight kinds of tools for biological or sequencing data analyses, including sequence alignment tools, functional genomics tools, comparative genomics tools, motif analysis tools, genome browser, primer design, and SSR analysis tools. In addition, eight kinds of graphs, including a box plot, Venn diagram, corrplot, Q-Q plot, Manhattan plot, seqLogo, volcano plot, and a heatmap, can be generated rapidly using NHCCDB. We have incorporated a search system for efficient mining of transcription factors and genes, along with an embedded data submit function in NHCCDB. We believe that the NHCCDB database will be a useful platform for non-heading Chinese cabbage research and breeding. [ABSTRACT FROM AUTHOR]

Current study was conducted to check the genetic exploration for quality aspect of brassica at Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad during 2017- 18. The parents and the crosses were evaluated following Randomized Complete Block Design (RCBD) with three replications. Highly significant differences were noted among all the genotypes for seed oil, seedcake protein, glucosinolate, oleic acid and erucic acid contents showing high genetic potential for improvement. Analysis for the general combining ability showed almost significant differences except for protein that showed maximum non-significant difference among the lines. Significant difference were also noted among testers except for protein and erucic acid. Specific combining ability showed both significant and non-significant differences in positive and negative directions. Analysis for the components of genetic variance indicated that non-additive gene action played a significant role for the inheritance of the traits. This was further continued by GCA/SCA ratio values (0.040, 0.023, 0.0174, -0.0026, 0.178) which were less than 1 that depicted non-additive variance involved in these traits so as to achieve homozygous line. On basis of oil, erucic acid, oleic acid and glucosinolate these combinations viz. UAF12 × Torch, Toria × Candle, UAF11 × Torch and Span × Candle, were selected for SCA effects relative heterosis, heterobeltiosis and GCA estimates. These combinations can be used as source of quality traits in further breeding program. [ABSTRACT FROM AUTHOR]

Utilization of nanoscale materials in agribusiness are as yet in earliest stages contrasted with clinical and mechanical areas. The effect of, zinc oxide nanoparticles and humic acid (HA) coated nanoparticles were evaluated for Brassica campestris seed germination. A simple one-pot method was used to synthesize HA/ZnO NPs involving zinc oxide nanoparticles (ZnO) core (20-35 nm in diameter) and humic acid shell. HA/ZnO NPs were used to investigate the effect on the germination profile of Brassica campestris. Germination profile parameters were measured as root-shoot length, germination index, fresh and dry weight for 15 days. HA/ZnO NPs were confirmed with various physicochemical techniques such as X-ray diffraction, Fourier transform infrared (FTIR), UV-Vis spectroscopy, and scanning electron microscopy (SEM).The data confirmed the adsorption of humic acid on the surface of ZnO nanoparticles. The HA/ZnO NPs exposure significantly increased germination by 83 %, root length (60 %), shoot length (78 %), fresh weight (71.4 %) and dry weight (45.9 %).. The HA/ZnO NPs were applied as co-fertilizer to upgrade the Brassica campestris seed germination. Seeds may have assimilated NPs, which thus might prompt the union of specific catalysts, working with the food activation. This investigation exhibited that HA/ZnO NPs can be a capable co-compost, giving zinc and HA to seed. [ABSTRACT FROM AUTHOR]

Male-sterile mutants are useful materials to study the anther and pollen development. Here, whole transcriptome sequencing was performed for inflorescences in three sterile lines of Chinese cabbage (Brassica campestris L. ssp. chinensis Makino, syn. B. rapa ssp. chinensis), the genic male-sterile line (A line), the Polima cytoplasmic male-sterile (CMS) line (P line), and the Ogura CMS line (O line) along with their maintainer line (B line). In total, 7,136 differentially expressed genes (DEGs), 361 differentially expressed long non-coding RNAs (lncRNAs) (DELs), 56 differentially expressed microRNAs (miRNAs) (DEMs) were selected out. Specific regulatory networks related to anther cell differentiation, meiosis cytokinesis, pollen wall formation, and tapetum development were constructed based on the abortion characteristics of male-sterile lines. Candidate genes and lncRNAs related to cell differentiation were identified in sporocyteless P line, sixteen of which were common to the DEGs in Arabidopsis spl / nzz mutant. Genes and lncRNAs concerning cell plate formation were selected in A line that is defected in meiosis cytokinesis. Also, the orthologs of pollen wall formation and tapetum development genes in Arabidopsis showed distinct expression patterns in the three different sterile lines. Among 361 DELs, 35 were predicted to interact with miRNAs, including 28 targets, 47 endogenous target mimics, and five precursors for miRNAs. Two lncRNAs were further proved to be functional precursors for bra-miR156 and bra-miR5718, respectively. Overexpression of bra-miR5718HG in B. campestris slowed down the growth of pollen tubes, caused shorter pollen tubes, and ultimately affected the seed set. Our study provides new insights into molecular regulation especially the ncRNA interaction during pollen development in Brassica crops. [ABSTRACT FROM AUTHOR]

Endophytic fungi (EPF) colonize plant roots and enhance their growth. The relationship between host plant and EPF can be affected by several factors, such as growth media, host species, and fungal species. The objective of this study was to clarify the effect of nutrient concentration in growth media on the relationship between host plant and root EPF. Brassica campestris was grown in 1/100 Murashige and Skoog (MS), 1/10 MS, 1/100 MS and 1/10 nitrogen (high N), and 1/100 MS and 1/10 phosphorus (high P) media. B. campestris was inoculated with four root EPFs isolated from forest soils in Indonesia and harvested 28 days after transplant. Shoot dry weight (SDW) and colonization in roots were measured. All the isolates colonized roots of B. campestris. Two isolates increased the SDW of B. campestris grown on 1/100 MS media. The shoot growth response of B. campestris to EPF colonization on 1/100 MS was higher than that on 1/100 high N and 1/100 high P MS media. These results suggest that concentration of nitrogen and phosphorus in growth media determine the relationship between B. campestris and root EPF. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Experimental Biology (Botany) is the property of Egyptian Society of Experimental Biology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The provision of ammonium (NH4+) and nitrate (NO3−) mixture increases the total nitrogen (N) than the supply of sole NH4+ or NO3– with the same concentration of total N; thus, the mixture contributes to better growth in Brassica campestris. However, the underlying mechanisms remain unknown. In this study, we analyzed NH4+ and NO3– fluxes using a scanning ion-selective electrode technique to detect under different N forms and levels in B. campestris roots. We observed that the total N influxes with NH4+ and NO3− mixture were 1.25- and 3.53-fold higher than those with either sole NH4+ or NO3−. Furthermore, NH4+ and NO3– might interact with each other under coexistence. NO3– had a positive effect on net NH4+ influx, whereas NH4+ had a negative influence on net NO3– influx. The ammonium transporter (AMT) played a key role in NH4+ absorption and transport. Based on expression analysis, BcAMT1.2 differed from other BcAMT1s in being upregulated by NH4+ or NO3−. According to sequence analysis and functional complementation in yeast mutant 31019b, AMT1.2 from B. campestris may be a functional AMT. According to the expression pattern of BcAMT1.2 , β-glucuronidase activity, and the cellular location of its promoter, BcAMT1.2 may be responsible for NH4+ transport. Following the overexpression of BcAMT1.2 in Arabidopsis , BcAMT1.2 -overexpressing lines grew better than wildtype lines at low NH4+ concentration. In the mixture of NH4+ and NO3–, NH4+ influxes and NO3– effluxes were induced in BcAMT1.2 -overexpressing lines. Furthermore, transcripts of N assimilation genes (AtGLN1.2 , AtGLN2 , and AtGLT1) were significantly upregulated, in particular, AtGLN1.2 and AtGLT1 were increased by 2.85–8.88 times in roots, and AtGLN1.2 and AtGLN2 were increased by 2.67–4.61 times in leaves. Collectively, these results indicated that BcAMT1.2 may mediate in NH4+ fluxes under the coexistence of NH4+ and NO3– in B. campestris. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) are important regulators in plant growth and development. Here the function of a lncRNA fragment was studied, which was predicted as an endogenous target mimic (eTM) of miR156 in Brassica campesrtis. Unexpectedly, the transformation of this lncRNA into Arabidopsis thaliana neither inhibited the expression of miR156a nor resulted in any phenotypes that differed from the control plants (CK). The full-length sequence of the lncRNA (named bra-miR156HG) was then obtained using RACE and transferred into A. thaliana. The transgenic plants displayed a delay in flowering time, an increasing number of rosette leaves, and a changed morphology of cauline leaves, which was similar to the plants that expressed bra-miR156a. In contrast, the overexpression of bra-miR156HG in B. campestris resulted in an increased tip angle of leaves and changed the length-width ratio of leaves at different nodes, suggesting that bra-miR156HG may be involved in regulating the leaf morphology. Collectively, our study showed that bra-miR156HG functions as a precursor of bra-miR156a involved in regulating plant flowering time and leaf development under different biological backgrounds. The secondary structure of lncRNA is essential not only for the normal roles that it plays but also for expanding the functional diversities. • Identified a lncRNA bra-miR156HG act as the precursor gene of miR156a. • Expressing bra-miR156HG in Arabidopsis thaliana affected flowering time and development of cauline leaves and trichomes. • Overexpression of bra-miR156HG in Brassica campestris caused the change of leaf morphology. • Illustrated that function of lncRNA depends on their secondary structure. [ABSTRACT FROM AUTHOR]

In flowering plants, stamen development is a complex multistage process, which is highly regulated by a series of transcription factors. In this study, BcMF28 , which encodes a R2R3-MYB transcription factor, was isolated from Brassica campestris. BcMF28 is localized in the nucleus and cytoplasm, and acts as a transcriptional activator. Quantitative real-time PCR and promoter activity analysis revealed that BcMF28 was predominately expressed in inflorescences. The expression of BcMF28 was specifically detected in tapetum, developing microspores, anther endothecium, and filaments during late stamen development. The overexpression of BcMF28 in Arabidopsis resulted in aberrant stamen development, including filament shortening, anther indehiscence, and pollen abortion. Detailed analysis of anther development in transgenic plants revealed that the degeneration of septum and stomium did not occur, and endothecium lignification was affected. Furthermore, the expression levels of genes involved in the phenylpropanoid metabolism pathway were altered in BcMF28 -overexpressing transgenic plants. Our results suggest that BcMF28 plays an important regulatory role during late stamen development. • BcMF28 encodes a R2R3-MYB transcriptional activator. • BcMF28 is predominantly expressed in inflorescences, especially in tapetum, microspores, anther endothecium and filaments. • BcMF28 overexpressing in Arabidopsis caused filament shortening, anther indehiscence, and pollen abortion.aberrant pollens, shorter filaments, and non-dehiscent anthers. • BcMF28 overexpressing in Arabidopsis altered gene expression involved in the phenylpropanoid metabolism pathway. [ABSTRACT FROM AUTHOR]

Conventional methods for gene function study in Brassica campestris have lots of drawbacks, which greatly hinder the identification of important genes' functions and molecular breeding. The clustered, regularly interspaced, short palindromic repeats (CRISPR) and CRISPR-associated protein 9 (CRISPR/Cas9) system is a versatile tool for genome editing that has been widely utilized in many plant species and has many advantages over conventional methods for gene function study. However, the application of CRISPR/Cas9 system in B. campestris remains unreported. The pectin-methylesterase genes Bra003491, Bra007665, and Bra014410 were selected as the targets of the CRISPR/Cas9 system. A single-targeting vector and a multitargeting vector were constructed. Different types of mutations were detected in T0 generation through Agrobacterium transformation. The mutation rate of the three designed sgRNA seeds varied from 20 to 56%. Although the majority of T0 mutants were chimeric, four homozygous mutants were identified. Transformation with the multitargeting vector generated one line with a large fragment deletion and one line with mutations in two target genes. Mutations in Bra003491 were stable and inherited by T1 and T2 generations. Nine mutants which did not contain T-DNA insertions were also obtained. No mutations were detected in predicted potential off-target sites. Our work demonstrated that CRISPR/Cas9 system is efficient on single and multiplex genome editing without off-targeting in B. campestris and that the mutations are stable and inheritable. Our results may greatly facilitate gene functional studies and the molecular breeding of B. campestris and other plants. [ABSTRACT FROM AUTHOR]

Pollen wall development is one of the key processes of pollen development. Several pectin methylesterase (PME) genes participate in pollen germination and pollen tube growth. However, the relationship between PME genes and pollen intine formation remains unclear. In this study, we investigated the expression and subcellular localization of the PME gene BcPME37c in Brassica campestris. Furthermore, morphology and cytology methods were used to examine the phenotype of the CRISPR/Cas9 system-induced BcPME37c mutant. We found that BcPME37c is predominately expressed in mature stamen and located at the cell wall. BcPME37c mutation causes the abnormal thickening of the pollen intine of B. campestris. Our study indicated that BcPME37c is required for pollen intine formation in B. campestris. • BcPME37c is expressed predominately in mature stamen and is located at the cell wall. • About 5.36% of the diameter of bcpme37c pollens were obviously increased after imbibition. • The intine of bcpme37c mature pollens were abnormal thickening. [ABSTRACT FROM AUTHOR]

Hydrogen gas (H 2) has been shown as an important factor in plant tolerance to abiotic stresses, but the underlying mechanisms remain unclear. In the present study, the effects of H 2 and its interaction with nitric oxide (NO) on alleviating cadmium (Cd) stress in Brassica campestris seedlings were investigated. NO donor (SNP) or hydrogen-rich water (HRW) treatment showed a significant improvement in growth of Cd-stressed seedlings. Cd treatment upregulated both endogenous NO and H 2 (36% and 66%, respectively), and the increase of H 2 was prior to NO increase. When treated with NO scavenger (PTIO) or NO biosynthesis enzyme inhibitors (L-NAME and Gln), HRW-induced alleviation under Cd stress was prevented. Under Cd stress, HRW pretreatment significantly enhanced the NO accumulation, and together up-regulated the activity of NR (nitrate reductase) and expression of NR. HRW induced lower reactive oxygen species (ROS), higher AsA content, enhanced activity of POD (peroxidase) and SOD (superoxide dismutase) in seedling roots were inhibited by PTIO, L-NAME and Gln. Through proteomic analysis, the level of 29 proteins were changed in response to H 2 and NO-induced amelioration of Cd stress. Nearly half of them were involved in oxidation-reduction processes (about 20%) or antioxidant enzymes (approximately 20%). These results strongly indicate that in Cd-stressed seedlings, pretreatment with HRW induces the accumulation of H 2 (biosynthesized or permeated), which further stimulates the biosynthesis of NO through the NR pathway. Finally, H 2 and NO together enhance the antioxidant capabilities of seedlings in response to Cd toxicity. Image 1 • SNP and HRW treatments both improve Cd tolerance of cabbage seedlings. • Cd increases the endogenous level of both H 2 and NO. • NO biosynthesis inhibitors and scavenger reverse HRW-induced improvement of Cd tolerance. • HRW enhances the accumulation of NO and the activity of NR under Cd stress. • Antioxidant enzymes are the response factors during the improvement of Cd tolerance induced by HRW and SNP. Nitric oxide was involved in the alleviation of cadmium stress mediated by hydrogen gas in Brassica campestris seedlings. [ABSTRACT FROM AUTHOR]

Abstract Pectin methylesterases (PMEs) catalyze pectin demethylation and facilitate the determination of the degree of methyl esterification of cell wall in higher plants. The regulation of PME activity through endogenous proteinaceous PME inhibitors (PMEIs) alters the status of pectin methylation and influences plant growth and development. In this study, we performed a PMEI screening assay using a chemical library and identified a strong inhibitor, phenylephrine (PE). PE, a small molecule, competitively inhibited plant PMEs, including orange PME and Arabidopsis PME. Physiologically, cultivation of Brassica campestris seedlings in the presence of PE showed root growth inhibition. Microscopic observation revealed that PE inhibits elongation and development of root hairs. Molecular studies demonstrated that R oot H air S pecific 12 (RHS12) encoding a PME, which plays a role in root hair development, was inhibited by PE with a Ki value of 44.1 μM. The biochemical mechanism of PE-mediated PME inhibition as well as a molecular docking model between PE and RHS12 revealed that PE interacts within the catalytic cleft of RHS12 and interferes with PME catalytic activity. Taken together, these findings suggest that PE is a novel and non-proteinaceous PME inhibitor. Furthermore, PE could be a lead compound for developing a potent plant growth regulator in agriculture. Highlights • Phenylephrine (PE) inhibits Pectin methylesterases (PMEs). • Phenylephrine (PE) serves as a competitive inhibitor of active PMEs. • Phenylephrine (PE) is a non-proteinaceous PME inhibitor. • Phenylephrine (PE) inhibits the growth of Brassica campestris seedlings. • Phenylephrine (PE) inhibits RHS12 (R oot H air S pecific 12), which PME plays a role in root hair development. [ABSTRACT FROM AUTHOR]

Abstract In this study, a cDNA of ICE1 (inducer of CBF expression 1) gene, named BcICE1 , was isolated from Brassica campestris 'Longyou 6'. The deduced protein has 499 amino acids containing a typical bHLH domain and is highly identical with AtICE1 (85.9%) from Arabidopsis thaliana. BcICE1 is located in the nucleus. The activities of SOD, CAT, POD, and APX and the transcriptional levels of SOD , CAT , and POD genes were higher in BcICE1-transgenic tobacco than in wild-type (WT) tobacco under cold stress. Compared with WT tobacco, proline, soluble sugar, and chlorophyll were enhanced, whereas malondialdehyde and relative conductivity were decreased in BcICE1-transgenic tobacco. The overexpression of BcICE1 in tobacco increased the expression of CBF1 , CBF2 , and other stress-related genes. Moreover, under salt and PEG (25%) stress, the activities of APX and GPX and content of soluble sugar and chlorophyll in BcICE1-transgenic tobacco were higher than those in WT tobacco. Our results suggest that BcICE1 plays an important role in the response to abiotic stress. Highlights • We identified cDNA of the BcICE1 gene from Brassica campestris. • BcICE1 is localized in the nucleus. • Overexpression of BcICE1 increases antioxidant enzyme activity in tobacco. • Overexpression of BcICE1 improves abiotic stress resistance of transgenic tobacco. • Overexpression of BcICE1 alters the expression of antioxidant enzyme genes and stress response genes in tobacco. [ABSTRACT FROM AUTHOR]

Key message: BcMF23a contributes to pollen wall development via influencing intine construction, which, in turn, influences pollen tube growth.Abstract: Pollen wall, the morphological out face of pollen, surrounds male gametophyte and plays an important role in plant reproduction. Pectin methylesterases (PMEs) are involved in pollen wall construction by de-esterifying pectin of the intine. In this study, the function of a putative pectin methylesterase gene, Brassica campestris Male Fertility 23a (BcMF23a), was investigated. Knockdown of BcMF23a by artificial microRNA (amiRNA) technology resulted in abnormal pollen intine formation outside of the germinal furrows at the binucleate stage. At the trinucleate stage, 20.69% of pollen possessed the degradation of nuclei, cytoplasm and the intine, resulting in shrunken pollen, whereas the remaining 75.86% were wall-disrupted with degrading cytoplasm and broken exine inside the germinal furrows. In addition, pollen abortion in transgenic plants caused germination percentage reduction by 19% in vitro and pollen tube growth disruption in natural stigma in vivo. Taken together, BcMF23a is involved in pollen development and pollen tube growth, possibly via participating in intine construction. This study may contribute towards understanding the function of pollen-specific PMEs and the molecular regulatory network of pollen wall development. [ABSTRACT FROM AUTHOR]

Extract of Brassica campestris was tested as potential corrosion inhibitor for Cor-Ten steel in NaCl and acidic solutions, simulating a marine and an urban-industrial environment, respectively. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were performed both in absence and in presence of the extract at room temperature. The surface chemical analysis was investigated by X-ray Photoemission Spectroscopy (XPS), before and after corrosion. Electrochemical results demonstrated that a very small concentration of Brassica campestris extracts can inhibit Cor-Ten corrosion in NaCl solution (inhibition efficiency of 80–84%) better than in acidic solutions. Surface analysis results confirmed these good results. [ABSTRACT FROM AUTHOR]

High temperature (HT) is a major environmental stress limiting oversummer production of nonheading Chinese cabbage (NHCC, Brassica campestris ssp. chinensis Makino). In the present study, the effects of HT on photosynthetic capacity, including light reaction and carbon assimilation, were completely investigated in two NHCC, 'xd' (heat-tolerant), and 'sym' (heat-susceptible). The two genotypes showed significant differences in plant morphology, photosynthetic capacity, and photosynthate metabolism (carboassimilation). HT caused a decrease in photosynthesis, chlorophyll contents, and photochemical activity in NHCC. However, these main photosynthetic-related parameters, including net photosynthetic rate (PN), maximal photochemical efficiency of PSII (Fv/Fm), and total chlorophyll content in 'xd', were significantly higher than those of 'sym' plants. The antioxidant contents and antioxidative enzyme activities of ascorbic acid-reduced glutathione cycle in the chloroplast of 'xd' were significantly higher than those of 'sym'. Microscopic analyses revealed that HT affected the structure of photosynthetic apparatus and membrane integrity to a different extent, whereas 'xd' could maintain a better integrated chloroplast shape and thylakoid. Inhibited light reaction also hampered carbon assimilation, resulting in a decline of carboxylation efficiency and imbalance of carbohydrate metabolism. However, larger declined extents in these data were presented in 'sym' (heat-susceptible) than 'xd' (heat-tolerant). The heat-tolerant genotype 'xd' had a better capacity for self-protection by improved light reaction and carbon assimilation responding to HT stress. [ABSTRACT FROM AUTHOR]

A study was conducted at the research area of Arid Zone Research Institute, Umerkot, Pakistan during the year 2012-13 using RCBD with three replications and six genotypes i.e. P-8 (UCD-8), P-14 (UCD-14), Gaj Sarhein, P-4 (UCD-4), Sindh Raya and S-9 (Check). According to results genotype S-9 (check) surpassed all other genotypes for plant height (208.00 cm). Sindh Raya showed superiority in branches per plant (6.73). Significantly more pods per plant (576.67) were noted in S-9 (check), but candidate genotypes P-4 (UCD-4) and P- 14 (UCD-14) (16.33 each) surpassed S-9 (14.0) for seeds per pod. Seed index was also significantly (P<0.05) greater (2.57 g) in candidate genotype P-4 (UCD- 4) and surpassed S-9 (2.52 g). None of the genotypes either could surpass or at par with S-9 (check) for seed yield per plant. Correlation results were positively significant among plant stature with pods plant (r = 0.8168**), height with yield of single plant (r = 0.6138**), days to flower with seed index (r = 0.5144*), days to flower with yield of single plant (r = 0.7523**), pods per plant with seed index (r = 0.6551**), pods per plant with single plant yield (r = 0.5541**), seed index with single plant yield (r = 0.5980**). Negative and significant relationship was examined between plant height and seeds per pod (r = -0.6832**), branches per plant and ripeness days (r = -0.4740*) and pods per plant and seeds per pod (r = -0.6794**). [ABSTRACT FROM AUTHOR]

Imbibed seeds of Brassica campestris cv-T-59 and cv-MYSL-203 with different doses (25 to 150 mg) of steel mill effluent had shown the variable response in terms of seed germination, seedling growth and total activities of certain enzymes in both cultivars. More sensitiveness was shown by cv-T-59. However, effect was cultivar, organ and enzyme specific. [ABSTRACT FROM AUTHOR]

The present study was carried out at the Research Farm of S.G. College of Agriculture and Research Station, Kumhrawand, Jagdalpur (C.G.), Indira Gandhi Krishi Vishwavidyalaya, Raipur (Chhattisgarh) during Rabi 2013-14. Experimental materials comprised 30 F1 from a 6 x 6 diallel crosses was grown in Randomized Complete Block Design with three replications with the objectives to estimate the genetic variability, heritability, genetic advance. Analysis of variance revealed presence of sufficient variability present as per different biometrical analysis except for days to maturity and oil content (%). Relative magnitude of phenotypic co-efficient of variation was higher than the genotypic co-efficient of variation. The high GCV and PCV were observed for only two traits viz. number of branches per plant and harvest index (%). The traits plant height (cm), siliqua length (cm), number of siliquae per plant and seed yield per plant had moderate GCV and PCV. The highest heritability estimates were observed for the traits erucic acid content followed by plant height, branches per plant, seed yield per plant, siliqua length, days to 50% flowering and harvest index (%). Genetic advance as percentage of mean was observed high for the character number of siliquae per plant, followed by seed yield per plant, days to maturity and plant height. [ABSTRACT FROM AUTHOR]

• In the late stage of mononuclear microspore, the tapetum of MS7-2 was abnormally expanded, resulting in the extrusion of microspores and the inability to undergo mitosis to form mature pollen grains, while the tapetum of MF7-2 degraded normally. • The differential expression of transcription factors related to anther and pollen development in MS7-2 may be related to anther abortion. • AHA9 and VHA-G3 related to ATP synthase were significantly down-regulated in MS7-2, which may lead to the formation of ROS by the combination of excess electrons and molecular oxygen. The accumulation of ROS in cells affected the PCD of tapetum. Male sterility is a complex developmental process involving the differentiation of different tissues and the coordinated expression of genes. It is not only used to produce hybrids with effective utilization of heterosis but also an ideal tool to study plant development networks. Here, we carried out morphological and cytological observations on the flower buds of the previously studied male-sterile mutant MS7-2 and its wild-type fertile plant MF7-2 at different developmental stages and performed transcriptomic and proteomic analyses. Compared with the anthers of MF7-2, the anthers of MS7-2 were obviously atrophied, the anther surface was concave, the tapetum was abnormally expanded at the mononuclear microspore stage and normal pollen grains could not be produced. Proteomic analysis showed that the differentially expressed proteins (DEPs) were mainly involved in lipid transport, lipid binding and lipase activity and were mainly concentrated in carbohydrate metabolism, biosynthesis of other secondary metabolites and lipid metabolism. Transcriptomic results showed that the differentially expressed genes (DEGs) were mainly related to cell membrane components and were significantly enriched in carbohydrate metabolism, lipid metabolism, membrane transport and other pathways. In addition, transcription factors involved in anther and pollen development were also found to be significantly down-regulated in MS7-2, such as AMS, bHLH66, bHLH69 and WRKY 34. Weighted gene coexpression network analysis (WGCNA) screened two key modules of anther abortion in wucai. The DEGs in the two modules were mainly enriched in the "terpenoid backbone biosynthesis," "pentose and glucuronate interconversions" and "cutin, suberine and wax biosynthesis" pathways, and three hub genes were screened as BraA02g028550.3C (LACS5), BraA01g016670.3C (VHA-G3) and BraA03g043400. 3C (AMS). Through transcriptomic and proteomic analyses, a regulatory network of MS7-2 male sterility of was constructed. It is speculated that the down-regulation of these genes and proteins in MS7-2 anthers inhibits the synthesis of some lipids and endogenous metabolites and accumulates a large amount of reactive oxygen species (ROS) in the tapetum, leading to the failure of normal PCD and the abortion of MS7-2. This study provides new insights into the molecular mechanism of male sterility in wucai. [ABSTRACT FROM AUTHOR]

• The Podu stage is critical to hypocotyl-tuber enlargement of turnip. • Auxin plays an important role in turnip hypocotyl-tuber enlargement at the early stages. • Transcriptome analysis identified hub genes involved in hypocotyl-tuber enlargement of turnip. Turnip (Brassica campestris L. ssp. rapifera Matag syn. B. rapa L.) is characterized by bulbous hypocotyl-tuber, which is an important agronomic trait of the Brassica plants, but the molecular mechanism underlying the development of turnip hypocotyl-tuber has rarely been explored. Contrary to turnip, pak-choi (B. campestris L. ssp. chinensis Makino syn. B. rapa ssp. chinensis) is characterized by small and long hypocotyl. Based on the difference in morphological and anatomical characteristics of hypocotyl between turnip and pak-choi at different developmental stages, integrative analysis was performed in this study. Comparative transcriptomic analysis demonstrated that the changes of expression patterns of genes related to plant hormones especially auxin in hypocotyl were closely related to turnip hypocotyl enlargement at the early stages (8 and 32 days after sowing). The immunolocalization of auxin during early hypocotyl development stages also showed auxin signal differences in secondary xylem of hypocotyl between the two subspecies, and further 1-Naphthaleneacetic acid (NAA) treatments confirmed the effect of auxin in turnip hypocotyl-tuber formation. Our study provided valuable information for further exploration of the role of auxin underlying turnip hypocotyl enlargement, enabling a more comprehensive understanding of plant storage organ development. [ABSTRACT FROM AUTHOR]

We investigated the effects of low nocturnal temperature on photosynthetic apparatus of winter rapeseed ( Brassica campestris L.). An artificial climate chamber was used to simulate the effects of low nocturnal temperature on seedling and stomatal morphology, chloroplast ultrastructure, photosynthetic parameters, and dry matter distribution and accumulation in two winter rapeseed cultivars, Longyou-7 (ultra coldresistant) and Tianyou-2 (weak cold resistance). Compared with those at diurnal/nocturnal temperatures of 20°/10°C (control), rapeseed seedlings at 20°/5°C had increased leaf chlorophyll content, deepened green leaf color, decreased stomatal conductance ( G), intercellular CO concentration ( C), and photosynthetic rate ( P), and improved root/shoot ratio; the majority of stomata remained open in Longyou-7 while those in Tianyou-2 were mostly closed or semi-closed. At diurnal/nocturnal temperatures of 20°/-5°C, rapeseed seedlings had decreased leaf chlorophyll content with increased C but decreased G and P; Tianyou-2 exhibited ruptured chloroplast membrane, dissolved grana, broken stroma lamella, and decreased root/shoot ratio, whereas Longyou-7 had chloroplasts retaining partial structure of grana with a small amount of starch granules in guard cells. Low nocturnal temperature damaged the photosynthetic membrane of chloroplasts and reduced P in the leaves of winter rapeseed influencing photosynthetic processes in this crop. The reduction of P was mainly related to stomatal limitation at diurnal/nocturnal temperatures of 20°/5°C and non-stomatal limitation at diurnal/nocturnal temperatures of 20°/-5°C. [ABSTRACT FROM AUTHOR]

Heat shock proteins (HSPs) exist extensively in eukaryotes and are conserved molecular chaperones with important contribution to plant's survival under environmental stresses. Here, the cloning and characterization of one complementary DNA (cDNA) designated as BcHSP70 from young seedlings of Brassica campestris were reported in the present work. Bioinformatic analysis revealed that BcHSP70 belongs to the plant HSP gene family and had the closest relationship with HSP70-4 from Arabidopsis thaliana. Constitutive overexpression of BcHSP70 in tobacco obviously conferred tolerance to heat stress by affecting different plant physiological parameters. In our study, transgenic tobaccos exhibited higher chlorophyll content than wild-type control when exposed to heat stress. Superoxide dismutase (SOD) and peroxidase (POD) activities, which were helpful to decrease the damage to the membrane system, were significantly higher in transformants compared to wild-type lines. Meanwhile, lower comparative electrical conductivity and malondialdehyde (MDA) content and higher proline and soluble sugar accumulation were found in transgenic tobaccos than in wild-type lines. All these above results indicated that this isolated BcHSP70 cDNA owned the ability to improve the tolerance to heat stress in transgenic tobacco, which provides helpful information and good basement to culture new robust B. campestris variety resistant to high-temperature stress by molecular breeding in the future. [ABSTRACT FROM AUTHOR]

An experiment was conducted to study the biochemical response of rapeseed (Brassica campestrisL.) to sulphur (S) fertilization at grey terrace soil. There were five treatments: S0(control), S1(20 kg S ha−1), S2(40 kg S ha−1), S3(60 kg S ha−1) and S4(80 kg S ha−1). Chlorophyll content in the leaf was determined at 30, 40, 50 and 60 days after emergence (DAE). The biochemical properties were found responsive to S. The highest chlorophyll content of mustard leaves was found in 60 kg S ha−1at 50 DAE. The same treatment also showed the maximum N content in the leaves at 45 DAE. The highest oil content was recorded in 60 kg S ha−1. Other chemical characters such as acid value, peroxide and saponification values were lowest in 60 kg S ha−1while iodine value was found highest in the same S level. Non-essential fatty acids such as palmitic, stearic and erucic acid were increased in the rapeseed with decrease in S level, whereas essential fatty acids were maximum in 60 kg S ha−1. Therefore, 60 kg S ha−1can be recommended to produce quality rapeseed in grey terrace soil of Bangladesh. [ABSTRACT FROM PUBLISHER]

Plant biomass, root growth and phosphorus (P) uptake can be strongly influenced by soil P availability; large amounts of P accumulate as residual P in agricultural soils due to over-application of fertilizer P. However, the dynamics of plant growth and P uptake in response to different residual P supply gradients during the whole growth cycle is not fully understood. Here, a 2-year field experiment with Brassica campestris was conducted to characterize the dynamic pattern of biomass accumulation and P uptake rates with different residual P supply throughout the growth cycle. The plants grown in the high residual-P treatment had greater biomass production and P uptake than the low residual-P plants throughout the growth cycle. The corresponding average rates of plant growth and P uptake were higher in high than low residual-P treatments till flowering, but no differences were observed thereafter. The rates of plant growth and P uptake increased with growth stages before flowering and then decreased. The maximum differences in plant growth and P uptake rate between low and high residual-P treatments were found at the flowering stage. Compared with low P supply, high residual-P supply enhanced root dry weight over time. Time of attaining maximum average daily biomass production rate was delayed by about 4 days at low soil residual-P supply. The results indicated that soil residual-P supply intensity regulated biomass production, growth rate, P uptake rate and the time of attaining maximum average daily biomass production rate, depending on growth stages. It is suggested that exploration of soil residual P by plant is closely associated with growth stages and the soil residual P supply intensity. [ABSTRACT FROM AUTHOR]

Brassica campestris pectate lyase-like 9 ( BcPLL9 ) was previously identified as a differentially expressed gene both in buds during late pollen developmental stage and in pistils during fertilization in Chinese cabbage. To characterize the gene's function, antisense-RNA lines of BcPLL9 ( bcpll9 ) were constructed in Chinese cabbage. Self- and cross-fertilization experiments harvested half seed yields when bcpll9 lines were used as pollen donors. In vivo and in vitro pollen germination assays showed that nearly half of the pollen tubes in bcpll9 were irregular with shorter length and uneven surface. Aniline blue staining identified abnormal accumulation of a specific bright blue unknown material in the bcpll9 pollen portion. Scanning electron microscopy observation verified the abnormal outthrust material to be near the pollen germinal furrows. Transmission electron microscopy observation revealed the internal endintine layer was overdeveloped and predominantly occupied the intine. This abnormally formed intine likely induced the wavy structure and growth arrest of the pollen tube in half of the bcpll9 pollen grains, which resulted in less seed yields. Collectively, this study presented a novel PLL gene that has an important function in B. campestris intine formation . [ABSTRACT FROM AUTHOR]

Cold stress is a key factor limiting the yield and quality of non-heading Chinese cabbage. The hydrophilic protective protein LEA plays an important role in plant abiotic stress. In this study, 72 BcLEAs were identified from non-heading Chinese cabbage and divided into 9 subfamilies by phylogenetic analysis. Gene structure analysis showed that BcLEAs were unevenly distributed on 10 chromosomes, with few introns. Through analyzing the expression of these genes under cold stress by RNA-seq and qRT-PCR, two genes (BcLEA4–7 and BcLEA4–18) highly sensitive to cold stress were identified, whose roles in cold tolerance of non-heading Chinese cabbage were demonstrated by virus-induced gene silencing. The BcLEA promoters were analyzed to study the cold response mechanism of BcLEA4–7 and BcLEA4–18 , revealing that both BcLEA4–7 and BcLEA4–18 promoters contained two CRT/DRE elements. Subsequently, it was found that the promoters isolated from non-heading Chinese cabbage could be activated at low temperatures. Further analysis showed BcCBF2 in non-heading Chinese cabbage interacted with two CRT/DRE elements in BcLEA4–7 and BcLEA4–18 promoters to stimulate their activity, indicating that BcCBF2 is an upstream regulator. Meanwhile, the CRT/DRE element located in BcLEA4–7 promoter (−219 bp to −171 bp) and BcLEA4–18 promoter (−234 bp to −186 bp) was more likely to be activated by BcCBF2 , which may be attributed to its flanking sequence. These data laid a foundation for further understanding the functional role and regulatory mechanism of BcLEAs in cold stress tolerance. • BcLEA family genes play an important role in cold tolerance of non-heading Chinese cabbage. • 72 BcLEA genes identified from non-heading Chinese cabbage. • CRT/DRE elements on BcLEA4-7 and BcLEA4-18 promoters can be activated by BcCBF2. • CRT/DRE elements on BcLEA4-7 and BcLEA4-18 promoters have distinct transcriptional activation activities. [ABSTRACT FROM AUTHOR]

PECTATE LYASE-LIKE10 ( PLL10) was previously identified as one of the differentially expressed genes both in microspores during the late pollen developmental stages and in pistils during the fertilization process in Chinese cabbage ( Brassica campestris ssp. chinensis). Here, antisense-RNA was used to study the functions of BcPLL10 in Chinese cabbage. Abnormal pollen was identified in the transgenic lines ( bcpll10-4, -5, and -6). In fertilization experiments, fewer seeds were harvested when the antisense-RNA lines were used as pollen donor. In vivo and in vitro pollen germination assays less germinated pollen tubes were observed in bcpll10 lines. Scanning electron microscopy observation verified that the tryphine materials were over accumulated around the pollen surface and sticked them together in bcpll10. Moreover, transmission electron microscopy observation revealed that the internal endintine was overdeveloped and predominantly occupied the intine, and disturbed the normal proportional distribution of the two layers in the non-germinal furrow region; and no obvious demarcation existed between them in the germinal furrow region in the bcpll10 pollen. Collectively, this study presented a novel PLL gene that played an important role during the pollen wall development in B. campestris, which may also possess potential importance for male sterility usage in agriculture. [ABSTRACT FROM AUTHOR]

This study, based on a greenhouse pot culture experiment conducted with 15-day-old rapeseed ( Brassica campestris L. cv. Pusa Gold; family Brassicaceae) and moong bean ( Vigna radiata L. Wilczek cv. Pusa Ratna; family Fabaceae) plants treated with cadmium (Cd) concentrations (0, 50, and 100 mg kg soil), investigates their potential for Cd accumulation and tolerance, and dissects the underlying basic physiological/biochemical mechanisms. In both species, plant dry mass decreased, while Cd concentration of both root and shoot increased with increase in soil Cd. Roots harbored a higher amount of Cd (vs. shoot) in B. campestris, while the reverse applied to V. radiata. By comparison, root Cd concentration was higher in B. campestris than in V. radiata. The high Cd concentrations in B. campestris roots and V. radiata shoots led to significant elevation in oxidative indices, as measured in terms of electrolyte leakage, HO content, and lipid peroxidation. Both plants displayed differential adaptation strategies to counteract the Cd burden-caused anomalies in their roots and shoots. In B. campestris, increasing Cd burden led to a significantly decreased reduced glutathione (GSH) content but a significant increase in activities of GSH reductase (GR), GSH peroxidase (GPX), and GSH sulfotransferase (GST). However, in V. radiata, increasing Cd burden caused significant increase in GSH content and GR activity, but a significant decline in activities of GPX and GST. Cross talks on Cd burden of tissues and the adapted Cd tolerance strategies against Cd burden-accrued toxicity indicated that B. campestris and V. radiata are good Cd stabilizer and Cd extractor, respectively, wherein a fine tuning among the major components (GR, GPX, GST, GSH) of the GSH redox system helped the plants to counteract differentially the Cd load-induced anomalies in tissues. On the whole, the physiological/biochemical characterization of the B. campestris and V. radiata responses to varying Cd concentrations can be of great help in elaborating the innovative plant-based remediation technologies for metal/metalloid-contaminated sites. [ABSTRACT FROM AUTHOR]

Background and Aims The arabinogalactan protein (AGP) gene family is involved in plant reproduction. However, little is known about the function of individual AGP genes in pollen development and pollen tube growth. In this study, Brassica campestris male fertility 8 (BcMF8), a putative AGP-encoding gene previously found to be pollen specific in Chinese cabbage (B. campestris ssp. chinensis), was investigated. Methods Real-time reverse transcription–PCR and in situ hybridization were used to analyse the expression pattern of BcMF8 in pistils. Prokaryotic expression and western blots were used to ensure that BcMF8 could encode a protein. Antisense RNA technology was applied to silence gene expression, and morphological and cytological approaches (e.g. scanning electron microscopy and transmission electron microscopy) were used to reveal abnormal phenotypes caused by gene silencing. Key Results The BcMF8 gene encoded a putative AGP protein that was located in the cell wall, and was expressed in pollen grains and pollen tubes. The functional interruption of BcMF8 by antisense RNA technology resulted in slipper-shaped and bilaterally sunken pollen with abnormal intine development and aperture formation. The inhibition of BcMF8 led to a decrease in the percentage of in vitro pollen germination. In pollen that did germinate, the pollen tubes were unstable, abnormally shaped and burst more frequently relative to controls, which corresponded to an in vivo arrest of pollen germination at the stigma surface and retarded pollen tube growth in the stylar transmitting tissues. Conclusions The phenotypic defects of antisense BcMF8 RNA lines (bcmf8) suggest a crucial function of BcMF8 in modulating the physical nature of the pollen wall and in helping in maintaining the integrity of the pollen tube wall matrix. [ABSTRACT FROM PUBLISHER]

Background microRNAs (miRNAs) are endogenous, noncoding, small RNAs that have essential regulatory functions in plant growth, development, and stress response processes. However, limited information is available about their functions in sexual reproduction of flowering plants. Pollen development is an important process in the life cycle of a flowering plant and is a major factor that affects the yield and quality of crop seeds. Results This study aims to identify miRNAs involved in pollen development. Two independent small RNA libraries were constructed from the flower buds of the male sterile line (Bcajh97-01A) and male fertile line (Bcajh97-01B) of Brassica campestris ssp. chinensis. The libraries were subjected to high-throughput sequencing by using the Illumina Solexa system. Eight novel miRNAs on the other arm of known pre-miRNAs, 54 new conserved miRNAs, and 8 novel miRNA members were identified. Twenty-five pairs of novel miRNA/miRNA* were found. Among all the identified miRNAs, 18 differentially expressed miRNAs with over two-fold change between flower buds of male sterile line (Bcajh97-01A) and male fertile line (Bcajh97-01B) were identified. qRT-PCR analysis revealed that most of the differentially expressed miRNAs were preferentially expressed in flower buds of the male fertile line (Bcajh97-01B). Degradome analysis showed that a total of 15 genes were predicted to be the targets of seven miRNAs. Conclusions Our findings provide an overview of potential miRNAs involved in pollen development and interactions between miRNAs and their corresponding targets, which may provide important clues on the function of miRNAs in pollen development. [ABSTRACT FROM AUTHOR]

In our previous work, a novel gene ( BcMF15) encoding a lipid transfer protein (LTP) was isolated from floral buds of Chinese cabbage pak choi ( Brassica campestris ssp. chinensis, syn. B. rapa ssp. chinensis) by cDNA-amplified fragment length polymorphism transcript profiling and rapid amplification of cDNA ends PCR. This LTP gene was exclusively expressed in the fertile line, indicating that this gene was related to male sterility. Functional analysis by RNA interference showed aberrant development and precocious degeneration of the tapetum. Pollen germination tests indicated that only 36 % of pollen from the transgenic lines can normally germinate. Morphological investigations showed that the transgenic plants developed smaller floral organs with thin anthers and lower amounts of pollen. Scanning electron microscopy revealed that the transgenic plants had higher numbers of abnormal pollen grains. Histological observations also demonstrated that microsporogenesis was suppressed and resulted in the failure of microspore maturation. These results demonstrated that BcMF15 played a major role in tapetum development, thereby providing valuable information on the biological function of LTP genes during pollen development. [ABSTRACT FROM AUTHOR]

Fertilization is controlled by a complex gene regulatory network. To study the fertilization mechanism, we determined time courses of the four developmental stages of fertilization in Chinese cabbage pak-choi ( Brassica campestris subsp. chinensis) by cytological observation. We then used the Arabidopsis ATH1 microarray to characterize the gene expression profiles of pollinated and unpollinated pistils in B. campestris subsp. chinensis. The result showed 44 up-regulated genes and 33 down-regulated genes in pollinated pistils compared with unpollinated pistils. Gene ontology analysis identified 20% of the up-regulated genes as belonging to the category of cell wall metabolism. We compared the up-regulated genes in pollinated pistils with previously identified pollen development related genes. Ten genes were found to be in common, which were termed as continuously expressed genes, in the two processes in the present article. Their expression patterns during pollen development and fertilization processes were then verified by RT-PCR. One of the continuously expressed genes, the homologous gene of At3g01270 in B. campestris subsp. chinensis, was confirmed as specifically expressed in microspores and pollinated pistils by using in situ hybridization. The potential biological functions of the other continuously expressed genes were also discussed. [ABSTRACT FROM AUTHOR]

Key message: BcMF11 as a non-coding RNA gene has an essential role in pollen development, and might be useful for regulating the pollen fertility of crops by antisense RNA technology. Abstract: We previously identified a 828-bp full-length cDNA of BcMF11, a novel pollen-specific non-coding mRNA-like gene from Chinese cabbage ( Brassica campestris L. ssp . chinensis Makino). However, little information is known about the function of BcMF11 in pollen development. To investigate its exact biological roles in pollen development, the BcMF11 cDNA was antisense inhibited in transgenic Chinese cabbage under the control of a tapetum-specific promoter BcA9 and a constitutive promoter CaMV 35S. Antisense RNA transgenic plants displayed decreasing expression of BcMF11 and showed distinct morphological defects. Pollen germination test in vitro and in vivo of the transgenic plants suggested that inhibition of BcMF11 decreased pollen germination efficiency and delayed the pollen tubes' extension in the style. Under scanning electron microscopy, many shrunken and collapsed pollen grains were detected in the antisense BcMF11 transgenic Chinese cabbage. Further cytological observation revealed abnormal pollen development process in transgenic plants, including delayed degradation of tapetum, asynchronous separation of microspore, and aborted development of pollen grain. These results suggest that BcMF11, as a non-coding RNA, plays an essential role in pollen development and male fertility. [ABSTRACT FROM AUTHOR]

Abstract: It is well established that exposure to ozone (O3) may impair vegetative growth and reproductive development in plants, although the consequences for yield depend on the effectiveness of the compensatory processes induced. This study examined the effects of exposing the terminal inflorescence of Brassica campestris L. to 100ppb O3 for 6hd−1 on four consecutive days during early flowering while the vegetative organs received charcoal-filtered air. The ordered predictability of development in B. campestris is ideal for studies of the impact of abiotic stress factors such as O3 on reproductive development and seed production. Effects on reproductive development and seed yield characteristics were determined for floral sites exposed at different developmental stages. Flower and pod numbers on the terminal raceme were unaffected by exposure, but effects on pod length varied depending on the developmental stage of floral sites during exposure. Increased ovule abortion and precocious seed germination in the pods of O3-treated plants reduced mature seed number pod−1. Although the individual weight of mature seeds was slightly greater in O3-treated plants, seed yield pod−1 and seed yield plant−1 were reduced due to the lower seed number pod−1. Seed from O3-treated plants germinated more rapidly than control seed irrespective of the stage of floral development during exposure. The results show that exposure to realistic O3 episodes during the early stages of flowering significantly reduced seed yield without impairing the vigour of the seeds produced. The physiological origins of these effects are discussed. [Copyright &y& Elsevier]

A polygalacturonase gene, designated BcMF17 ( Brassica campestris Male Fertility 17), has been cloned from Brassica campastris. This gene, encoding polygalacturonase (PG), consists of a 1,194 bp open reading frame along with four exons and three introns, and exhibits 79% similarities to BcMF9 (Huang et al. ). Detailed multiple amino acid sequence alignment and phylogenetic tree analysis indicate that BcMF17 belongs to a pollen clade and may be involved in pollen wall formation. Multiple alignments against homologous sequences from the genus Brassica indicate that BcMF17 is highly conserved in this genus. Quantitative real-time PCR results indicate that transcripts of BcMF17 are preferentially expressed in reproductive tissues, especially abundant in male floral tissues, but are expressed at low level in vegetative tissues. BcMF17 transcripts in male floral tissues persist from the anther primordia stage till to the mature pollen stage. In situ hybridized signals of BcMF17 are highly detected during anther development. During anther development, expression patterns of BcMF17 are very similar to those of BcMF9; however, unlike BcMF9, BcMF17 is continuously expressed during this period, and its transcripts are detected in the whole plant during its life cycle. [ABSTRACT FROM AUTHOR]

Chinese cabbage is a less known vegetable, not only in Transylvania, but all over our country, although it appears more and more often in the markets. In the present research, which took place in 2010 from September to December, the behavior of Chinese cabbage in Transylvanian area specific conditions was studied, in order to establish optimal planting period in autumn cultures. The experiment was realized in polyethylene tunnel and one of the objectives was to obtain a high yield of good quality. [ABSTRACT FROM AUTHOR]

Background and Aims: The polygalacturonase (PG) gene family has been found to be enriched in pollen of several species; however, little is currently known about the function of the PG gene in pollen development. To investigate the exact role that the PG gene has played in pollen development and about this family in general, one putative PG gene, Brassica campestris Male Fertility 9 (BcMF9), was isolated from Chinese cabbage (Brassica campestris ssp. chinensis, syn. B. rapa ssp. chinensis) and characterized. [ABSTRACT FROM PUBLISHER]