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Brassica napus cultivars have little or no primary dormancy; however, they are prone to secondary dormancy induction. Secondary dormant seeds can produce volunteer plants, which can result in genetic contamination, reduced quality and biosafety issues. However, information regarding the molecular mechanism underlying secondary dormancy is limited. The MOTHER OF FT AND TFL1 (MFT) gene, which is evolutionarily conserved in the plant kingdom, acts in a complex gene network in the seed dormancy or germination processes. In this study, we identified four B. napus genes that share high homology with AtMFT, named as BnaMFT. Analyses of cis-acting elements showed that BnaMFT promoters contain multiple seed-specific regulatory elements, and various stress- and hormone-responsive elements. Further experiments validated that BnaMFTs were specifically expressed during seed maturation and in the dry seed, with peaks at 35–42 days after pollination. BnaMFTs were not sufficient for primary dormancy; however, they were significantly enhanced by secondary dormancy induction with PEG6000 treatment. Moreover, BnaMFT transcripts were elevated by treatment with abscisic acid (ABA), which is known to be accumulated during secondary dormancy. These results collectively suggest that increased BnaMFT transcription levels are associated with secondary dormancy induction in an ABA-dependent manner in B. napus.

Lithium metal is among the most promising anode candidates of high-energy-density batteries. However, the formed dendrites result in low Coulombic efficiency and serious security issues. Designing lithiophilic sites is one of the effective strategies to control Li deposition. Herein, we propose a three-dimensional lithiophilic N-rich carbon nanofiber with the decoration of ZnO granules as a protective layer for a dendrite-free lithium metal anode. Theoretical evaluation indicates the synergistic effects of lithiophilic ZnO and N-containing functional groups enhance lithium adsorption and trigger uniform deposition. With the lithiophilic interlayer, the lithium deposition overpotential is only ∼20, 50, and 74 mV at 1, 3, and 6 mA cm-2, respectively, which are much lower than those without the functional interlayer (∼55, 130, and 238 mV). The average Coulombic efficiency of lithium stripping and plating is up to ∼97.4% (94.0% for that without the interlayer) at 0.5 mA cm-2. Meanwhile, the Li|LiFePO4 full cell with the superlithiophilic interlayer demonstrates a high capacity retention rate of 99.6% (91.0% for that without the interlayer) over 200 cycles at 1 C. The introduction of the lithiophilic interphase could provide a convenient strategy and guidance to design the configuration for the practical application of Li metal batteries.

With the intensification of global warming, extreme weather events have occurred more frequently, among which cold stress has become one of the major environmental factors that restrict global crop yield and production. Multiple long noncoding RNAs (lncRNAs) have been predicted or recognized in the plant response to cold stress, however, the molecular biological functions of most of these RNAs are still poorly understood. Here, we identified a novel lncRNA, COLD INDUCED lncRNA 1 (CIL1), as a positive regulator of the plant response to cold stress in Arabidopsis. CIL1 was significantly induced when the plant was exposed to cold stress. Moreover, knockdown mutants showed more sensitivity to cold stress than the wild type did, accompanied by an increased content of endogenous ROS (reactive oxygen species) and reduced osmoregulatory substances. Genome-wide transcriptome analysis indicated that 256 genes were downregulated and 34 genes were upregulated in cil1 mutants under cold stress, which were mainly involved in hormone signal transduction, ROS homeostasis and glucose metabolism. Our study implies that CIL1 has a positive effect on the plant response to cold stress by regulating the expression of multiple stress-related genes during the seedling stage.

Low temperature germination (LTG) is a key agronomic trait in rice (

Effects of transgenic crops on soil microbial communities are important constituents in ecological risk assessment. The Illumina MiSeq sequencing method was employed to examine the effects of transgenic glufosinate-resistant rapeseed and the associated herbicide application on rhizospheric bacterial communities at different growth stages. Our results showed that both transgenic rapeseed and the application of herbicide Basta (active ingredient: glufosinate) had no significant influence on alpha-diversity of rhizospheric bacterial communities. The dominant phyla across all samples were Proteobacteria, Bacteroidetes, Acidobacteria, Gemmatimonadetes and Actinobacteria. These dominant phyla show no remarkable differences under transgenic rapeseed, transgenic rapeseed with glufosinate applied, and non-transgenic acceptor counterpart rapeseed. Nevertheless, they respond differently at different growth stages. These results indicate that community variation was strongly dependent on the growth stage. Therefore, growing glufosinate-resistant transgenic rapeseed line Z7B10 and application of glufosinate herbicide had no adverse effects on the rhizospheric bacterial community composition.

Single-atom catalyst (SAC) have received increasing attention in the field of CO oxidation due to their higher catalytic activity and greater atomic utilization. The CO oxidation by O 2 on the single Rh atom embeddedover Graphdiyne (Rh-GDY) is systematically studied by using the first principles simulation . It is found that Rh atom can be stably and isolated in the GDY as a single metal atom binding to the carbon atoms. Both of the Langmuir–Hinshelwood (LH) and the Trimolecular Eley-Rideal (TER) mechanisms are preferable due to the rather low reaction barrier of their rate-determining steps. Moreover, LH mechanism could be more preferable than the TER mechanism according to their reaction rate constants at various temperatures, indicating that Rh-GDY is a promising catalyst for CO oxidation. Our investigation would help to reveal the mechanisms of the CO oxidation on SAC and shed light on the design of SAC based on GDY sheets for the oxidation of the fuel gas .

Background Brassica napus L. has little or no primary dormancy, but exhibits great variation in secondary dormancy. Secondary dormancy potential in oilseed rape can lead to the emergence of volunteer plants that cause genetic contamination, reduced quality and biosafety issues. However, the mechanisms underlying secondary dormancy are poorly understood. In this study, cultivars Huaiyou-WSD-H2 (H) and Huaiyou-SSD-V1 (V), which exhibit low (approximately 5%) and high (approximately 95%) secondary dormancy rate, respectively, were identified. Four samples, before (Hb and Vb) and after (Ha and Va) secondary dormancy induction by polyethylene glycol (PEG), were collected to identify the candidate genes involved in secondary dormancy via comparative transcriptome profile analysis. Results A total of 998 differentially expressed genes (DEGs), which are mainly involved in secondary metabolism, transcriptional regulation, protein modification and signaling pathways, were then detected. Among these DEGs, the expression levels of those involved in the sulfur-rich indole glucosinolate (GLS)-linked auxin biosynthesis pathway were markedly upregulated in the dormant seeds (Va), which were validated by qRT-PCR and subsequently confirmed via detection of altered concentrations of indole-3-acetic acid (IAA), IAA conjugates and precursors. Furthermore, exogenous IAA applications to cultivar H enhanced secondary dormancy. Conclusion This study first (to our knowledge) elucidated that indole GLS-linked auxin biosynthesis is enhanced during secondary dormancy induced by PEG, which provides valuable information concerning secondary dormancy and expands the current understanding of the role of auxin in rapeseed. Electronic supplementary material The online version of this article (10.1186/s12870-019-1866-z) contains supplementary material, which is available to authorized users.

Figure S1. RNA quality was qualified by agarose gel electrophoresis (A) and RIN value (B). Figure S2. Distribution of read coverage against the reference genome of oilseed rape. Figure S3. Correlation analyses for each sample among three repetitions. Figure S4. Overview of the expression of genes in Va, Vb, Ha and Hb implicated in cellular metabolism (A) and regulation (B) pathways. Figure S5. Volcano plots for the total expressed genes among Ha vs Hb, Va vs Ha, Va vs Vb and Vb vs Hb. Figure S6. KEGG enrichment analysis corresponding to the secondary dormancy candidate DEGs. Figure S7. The MapMan overview of the cellular metabolism process (A) and regulation pathway (B) in which 998 DEGs are involved in. Figure S8. Germination assay with exogenous IAA application to Hb. Figure S9. Effects of ABA and IAA on secondary dormancy. Figure S10. Validation of 12 randomly selected DEGs via qRT-PCR. (DOCX 4606 kb)

Secondary seed dormancy (SSD) is responsible for volunteer plants in canola fields, which causes a series of problems in canola production and serves as an important trait for the environmental safety assessment of transgenic canola. A canola cultivar with strong SSD was used to establish insight into seed transcriptomes in its secondarily dormant seeds and control seeds without dormancy by RNA-seq analysis, aiming to determine the molecular ecological characterizations of SSD. A dataset (more than 4 Gb) of valid sequences was obtained from each sample, which was combined to carry out the de novo assembling. The assembled sequences consisted of 314,261 fragments with length > 100 bp, including 29,740 long transcripts of length ≥ 500 bp. Functional annotation indicated that 1,641 long transcripts could be categorized into 24 cluster of orthologous groups of proteins (COGs) and 16,515 transcripts were linked to 2,648 gene ontology (GO) terms. There were 452 long transcripts with significantly different expression identified by a threshold of > 2-fold expression change (P

Development of new technologies for evaluating genetically modified (GM) crops has revealed that there are unintended insertions and expression changes in GM crops. Profiling techniques are non-targeted approaches and are capable of detecting more unintended changes in GM crops. Here, we report the application of a comparative proteomic approach to investigate the protein profile differences between a GM rice line, which has a lysine-rich protein gene, and its non-transgenic parental line. Proteome analysis by two-dimensional gel electrophoresis (2-DE) and mass spectrum analysis of the seeds identified 22 differentially expressed protein spots. Apart from a number of glutelins that were detected as targeted proteins in the GM line, the majority of the other changed proteins were involved in carbohydrate metabolism, protein synthesis and stress responses. These results indicated that the altered proteins were not associated with plant allergens or toxicity.

In the paper, based on outlining the making principle of the metal material super-plasticity and some making methods, a new making technology is proposed on the super-plasticity-shaping aided by laser in the vacuum negative pressure condition. The paper discusses the laser beams coupling characters in making process and the super-plasticity-shaping technology of the alloy materials, gives the shaping conditions of the typical materials for the vacuum negative pressure case.

The isolation distance required for field trials of genetically modified (GM) rapeseed varies widely worldwide, with a 50–400 m distance in most nations contrasting with a minimum 1000-m isolation distance in China. The goal of this study was to evaluate the relevance of current regulations in China regarding the isolation distance needed for GM rapeseed trials. A pollen flow experiment was conducted based on the design of concentric circles, with the GM plants in a 20-m diameter circle at the centre, surrounded by non-GM plants to a distance 60 m from the perimeter of the circle containing GM plants. The rate of pollen flow was the highest at the isolation distance of 0.5 m, where it ranged from 2.3091% to 2.6711%. The general pattern of the pollen flow rate (y) with distance (x) was well described by the equation y = 1.3936x-0.9136 (R 2 = 0.9950). The long-distance pollen flow tested at the isolation distance of 800 m was 0.0018%, which agrees with the theoretical prediction. The results suggested that 300 m, rather than 1000 m, is a reasonable distance to ensure a tolerable threshold of pollen flow (less than 0.01%) under conditions of winter rapeseed production in China.

Evaluating exogenous protein expressed in transgenic crops is one of the most effective methods of assessing the safety of transgenic plants. The objective of this study was to assess the food safety of genetically modified (GM) rice containing a lysine-rich fusion protein gene (transgenic GL gene rice) by in vitro digestion and acute toxicity testing of exogenous protein, according to the national standard of the People’s Republic of China. The exogenous protein was rapidly degraded in the simulated gastric and intestinal fluids. In the acute experiment, the exogenous protein was injected into Institute of Cancer Research (ICR) mice via the tail vein at a dose of 438 mg kg−1 body weight. No adverse effects on animal behavior or mortality were observed during the following 15-day period and there were no significant biological changes in body weight, serum biochemistry parameters, relative organ weights or histopathological examinations, compared with the control group. Therefore, exogenous protein in transgenic GL gene rice has a low potential allergenicity or toxicity risk.