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ABSTRACTSoybean is one of the important oil crops and a major source of protein and lipids. Drought can cause severe soybean yields. Dehydrin protein (DHN) is a subfamily of LEA proteins that play an important role in plant responses to abiotic stresses. In this study, the soybean GmDHN9 gene was cloned and induced under a variety of abiotic stresses. Results showed that the GmDHN9 gene response was more pronounced under drought induction. Subcellular localization results indicated that the protein was localized in the cytoplasm. The role of transgenic Arabidopsis plants in drought stress response was further studied. Under drought stress, the germination rate, root length, chlorophyll, proline, relative water content, and antioxidant enzyme content of transgenic Arabidopsis thaliana transgenic genes were higher than those of wild-type plants, and transgenic plants contained less O2−, H2O2 and MDA contents. In short, the GmDHN9 gene can regulate the homeostasis of ROS and enhance the drought resistance of plants.

ABSTRACTMaize (Zea mays L.) is the most important cereal crop in the world. Flowering period and photoperiod play important roles in the reproductive development of maize. This study, investigated ZmMADS42, a gene that is highly expressed in the shoot apical meristem. Agrobacterium infection was used to successfully obtain overexpressed ZmMADS42 plants. Fluorescence quantitative PCR revealed that the expression of the ZmMADS42 gene in the shoot apical meristem of transgenic plants was 2.8 times higher than that of the wild-type(WT). In addition, the expression of the ZmMADS42 gene in the endosperm was 2.4 times higher than that in the wild-type. The seed width of the T2 generation increased by 5.35%, whereas the seed length decreased by 7.78% compared with that of the wild-type. Dissection of the shoot tips of transgenic and wild-type plants from the 7-leaf stage to the 9-leaf stage revealed that the transgenic plants entered the differentiation stage earlier and exhibited more tassel meristems during their vegetative growth period. The mature transgenic plants were approximately 20 cm shorter in height and had a lower panicle position than the wild-type plants. Comparing the flowering period, the tasseling, powdering, and silking stages of the transgenic plants occurred 10 days earlier than those of the wild-type plants. The results showed that the ZmMADS42 gene played a significant role in regulating the flowering period and plant height of maize.

Summary: Examining nasal mucosa samples is crucial for nasal cavity disease research and diagnosis. Simultaneously obtaining high-quality data for single-cell transcriptomics (single-cell RNA sequencing [scRNA-seq]) and epigenomics (single-cell assay for transposase-accessible chromatin using sequencing [scATAC-seq]) of nasal mucosa tissues is challenging. Here, we present a protocol for processing human nasal mucosa samples to obtain data for both scRNA-seq and scATAC-seq. We describe steps for extracting human nasal mucosa tissue, mechanical and enzymatic dissociation, lysis of red blood cells, and a viability assay. We then detail procedures for library preparation and quality control. : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.

Maize (Zea mays L.) is a food crop sensitive to low temperatures. As one of the abiotic stress hazards, low temperatures seriously affect the yield of maize. However, the genetic basis of low-temperature adaptation in maize is still poorly understood. In this study, maize S-adenosylmethionine decarboxylase (SAMDC) was localized to the nucleus. We used Agrobacterium-mediated transformation technology to introduce the SAMDC gene into an excellent maize inbred line variety GSH9901 and produced a cold-tolerant transgenic maize line. After three years of single-field experiments, the contents of polyamines (PAs), proline (Pro), malondialdehyde (MDA), antioxidant enzymes and ascorbate peroxidases (APXs) in the leaves of the transgenic maize plants overexpressing the SAMDC gene significantly increased, and the expression of elevated CBF and cold-responsive genes effectively increased. The agronomic traits of the maize overexpressing the SAMDC gene changed, and the yield traits significantly improved. However, no significant changes were found in plant height, ear length, and shaft thickness. Therefore, SAMDC enzymes can effectively improve the cold tolerance of maize.

Abstract Ammonia borane (AB), a liquid hydrogen storage material, has attracted increasing attention for hydrogen utilization because of its high hydrogen content. However, the slow kinetics of AB hydrolysis and the indefinite catalytic mechanism remain significant problems for its large‐scale practical application. Thus, the development of efficient AB hydrolysis catalysts and the determination of their catalytic mechanisms are significant and urgent. A summary of the preparation process and structural characteristics of various supported catalysts is presented in this paper, including graphite, metal‐organic frameworks (MOFs), metal oxides, carbon nitride (CN), molybdenum carbide (MoC), carbon nanotubes (CNTs), boron nitride (h‐BN), zeolites, carbon dots (CDs), and metal carbide and nitride (MXene). In addition, the relationship between the electronic structure and catalytic performance is discussed to ascertain the actual active sites in the catalytic process. The mechanism of AB hydrolysis catalysis is systematically discussed, and possible catalytic paths are summarized to provide theoretical considerations for the designing of efficient AB hydrolysis catalysts. Furthermore, three methods for stimulating AB from dehydrogenation by‐products and the design of possible hydrogen product‐regeneration systems are summarized. Finally, the remaining challenges and future research directions for the effective development of AB catalysts are discussed.

Flowering is an essential process in plant development, and there are six major flowering pathways: the photoperiodic pathway, gibberellin pathway, vernalization pathway, age pathway, autonomous pathway, and temperature pathway. In this study, we screened the transcriptome sequencing of early flowering mutants from the laboratory for the significantly differentially expressed ZmGRAS46, which belongs to the DELLA subfamily of the GRAS family. DELLA is involved in the gibberellin pathway to regulate plant flowering. However, it is not clear whether ZmGRAS46 is involved in the gibberellin pathway which regulates plant flowering; therefore, in this experiment, we investigated the regulatory role of this gene in Arabidopsis flowering by overexpressing ZmGRAS46. It was found that overexpression of ZmGRAS46 in Arabidopsis promotes the formation of rosette leaves and flower buds and delays flowering time in Arabidopsis, and experiments have shown that ZmGRAS46 represses the expression of FLOWERING LOCUS T (FT), SUPPRESSOR OF CONSTANS1 (SOC1), CONSTANS (CO), and LEAFY (LFY). Our results indicated the possibility that ZmGRAS46 represses flowering through the CO-FT-SOC1-mediated photoperiodic flowering pathway. The delayed flowering phenotype of overexpressing ZmGRAS46 Arabidopsis could be rescued by applying GA3. The experimental results indicate that ZmGRAS46 depends on the GA3 pathway to regulate flowering in Arabidopsis.

Over the past few decades, the design and development of advanced materials based on two-dimensional (2D) ultra-thin materials for efficient energy catalysis and storage have aroused much attention. 2D ultra-thin materials have emerged as the most promising candidates for energy catalysis and storage because of their unique physical, chemical, and electronic properties. Herein, we review the research and application of 2D ultra-thin material-based catalysts for heterogeneous catalysis. The various catalysts based on 2D ultra-thin materials, such as MXenes, GO, black phosphorus, and h-BN, are discussed in detail for catalytic processes in the fields of electrocatalysis, photocatalysis, and energy catalysis. The fundamental relationships between the electronic structure and catalytic activity of 2D ultra-thin materials were described at the atomic level. A significant emphasis on the development of 2D ultra-thin materials and their intrinsic activity and stability was presented. Finally, the prediction and prospection of the future development of 2D ultra-thin materials as efficient nanomaterials are also conveyed. It is important to thoroughly understand and summarize such 2D ultra-thin materials to provide further guidance for structural optimization and performance improvement.

Abstract Background The plant architecture traits of maize determine the yield. Plant height, ear position, leaf angle above the primary ear and internode length above the primary ear together determine the canopy structure and photosynthetic efficiency of maize and at the same time affect lodging and disease resistance. A flat and tall plant architecture confers an obvious advantage in the yield of a single plant but is not conducive to dense planting and results in high rates of lodging; thus, it has been gradually eliminated in production. Although using plants that are too compact, short and density tolerant can increase the yield per unit area to a certain extent, the photosynthetic efficiency of such plants is low, ultimately limiting yield increases. Genetic mapping is an effective method for the improvement of plant architecture to identify candidate genes for regulating plant architecture traits. Results To find the best balance between the yield per plant and the yield per unit area of maize, in this study, the F2:3 pedigree population and a RIL population with the same male parent were used to identify QTL for plant height (PH), ear height (EH), leaf angle and internode length above the primary ear (LAE and ILE) in Changchun and Gongzhuling for 5 consecutive years (2016–2020). A total of 11, 13, 23 and 13 QTL were identified for PH, EH, LAE, and ILE, respectively. A pleiotropic consistent QTL for PH overlapped with that for EH on chromosome 3, with a phenotypic variation explanation rate from 6.809% to 21.96%. In addition, there were major consistent QTL for LAE and ILE, and the maximum phenotypic contribution rates were 24.226% and 30.748%, respectively. Three candidate genes were mined from the three consistent QTL regions and were involved in the gibberellin-activated signal pathway, brassinolide signal transduction pathway and auxin-activated signal pathway, respectively. Analysis of the expression levels of the three genes showed that they were actively expressed during the jointing stage of vigorous maize growth. Conclusions In this study, three consistent major QTL related to plant type traits were identified and three candidate genes were screened. These results lay a foundation for the cloning of related functional genes and marker-assisted breeding of related functional genes.

Maize (Zea mays L.) is an annual gramineous herb and is among the world’s most important crop species. Drought is the main factor contributing to maize yield reduction. The lateral organ boundaries domain (LBD) proteins belong to a class of higher-plant-specific transcription factors. LBD proteins usually include the highly conserved lateral organ boundaries (LOB) domains that play essential roles in plant growth and response to biotic stresses. However, few studies have addressed the biological functions of LBD genes associated with maize response to drought. Here we cloned the ZmLBD2 gene from maize and described its role in combating drought. Investigating ZmLBD2 subcellular localization, we show that it localizes to the cell nucleus and can specifically bind with inverted repeats of “GCGGCG”. Under drought stress, Arabidopsis thaliana overexpressing ZmLBD2 performed better than the wild-type plants in terms of seed germination rates, root length, relative water content, fresh weight, chlorophyll content, proline content, and antioxidant enzyme content. Arabidopsis overexpressing ZmLBD2 contained less MDA, H2O2, and O2− than the wild-type plants. Our protein-protein interaction results indicate an interaction between the ZmLBD2 and ZmIAA5 genes. In conclusion, the ZmLBD2 gene positively regulates H2O2 homeostasis in plants, strengthening drought resistance.

Drought is among the most serious environmental issue globally, and seriously affects the development, growth, and yield of crops. Maize (Zea mays L.), an important crop and industrial raw material, is planted on a large scale worldwide and drought can lead to large-scale reductions in maize corn production; however, few studies have focused on the maize root system mechanisms underlying drought resistance. In this study, miRNA–mRNA analysis was performed to deeply analyze the molecular mechanisms involved in drought response in the maize root system under drought stress. Furthermore, preliminary investigation of the biological function of miR408a in the maize root system was also conducted. The morphological, physiological, and transcriptomic changes in the maize variety “M8186” at the seedling stage under 12% PEG 6000 drought treatment (0, 7, and 24 h) were analyzed. With prolonged drought stress, seedlings gradually withered, the root system grew significantly, and abscisic acid, brassinolide, lignin, glutathione, and trehalose content in the root system gradually increased. Furthermore, peroxidase activity increased, while gibberellic acid and jasmonic acid gradually decreased. Moreover, 32 differentially expressed miRNAs (DEMIRs), namely, 25 known miRNAs and 7 new miRNAs, and 3,765 differentially expressed mRNAs (DEMRs), were identified in maize root under drought stress by miRNA-seq and mRNA-seq analysis, respectively. Through combined miRNA–mRNA analysis, 16 miRNA–target gene pairs, comprising 9 DEMIRs and 15 DEMRs, were obtained. In addition, four metabolic pathways, namely, “plant hormone signal transduction”, “phenylpropane biosynthesis”, “glutathione metabolism”, and “starch and sucrose metabolism”, were predicted to have important roles in the response of the maize root system to drought. MiRNA and mRNA expression results were verified by real-time quantitative PCR. Finally, miR408a was selected for functional analysis and demonstrated to be a negative regulator of drought response, mainly through regulation of reactive oxygen species accumulation in the maize root system. This study helps to elaborate the regulatory response mechanisms of the maize root system under drought stress and predicts the biological functions of candidate miRNAs and mRNAs, providing strategies for subsequent mining for, and biological breeding to select for, drought-responsive genes in the maize root system.

Abstract Background Breeding for new maize varieties with propitious root systems has tremendous potential in improving water and nutrients use efficiency and plant adaptation under suboptimal conditions. To date, most of the previously detected root-related trait genes in maize were new without functional verification. In this study, seven seedling root architectural traits were examined at three developmental stages in a recombinant inbred line population (RIL) of 179 RILs and a genome-wide association study (GWAS) panel of 80 elite inbred maize lines through quantitative trait loci (QTL) mapping and genome-wide association study. Results Using inclusive composite interval mapping, 8 QTLs accounting for 6.44–8.83 % of the phenotypic variation in root traits, were detected on chromosomes 1 (qRDWv3-1-1 and qRDW/SDWv3-1-1), 2 (qRBNv1-2-1), 4 (qSUAv1-4-1, qSUAv2-4-1, and qROVv2-4-1), and 10 (qTRLv1-10-1, qRBNv1-10-1). GWAS analysis involved three models (EMMAX, FarmCPU, and MLM) for a set of 1,490,007 high-quality single nucleotide polymorphisms (SNPs) obtained via whole genome next-generation sequencing (NGS). Overall, 53 significant SNPs with a phenotypic contribution rate ranging from 5.10 to 30.2 % and spread all over the ten maize chromosomes exhibited associations with the seven root traits. 17 SNPs were repeatedly detected from at least two growth stages, with several SNPs associated with multiple traits stably identified at all evaluated stages. Within the average linkage disequilibrium (LD) distance of 5.2 kb for the significant SNPs, 46 candidate genes harboring substantial SNPs were identified. Five potential genes viz. Zm00001d038676, Zm00001d015379, Zm00001d018496, Zm00001d050783, and Zm00001d017751 were verified for expression levels using maize accessions with extreme root branching differences from the GWAS panel and the RIL population. The results showed significantly (P

Maize is native to the tropics and is very sensitive to photoperiod. Planting in temperate regions with increased hours of daylight always leads to late flowering, sterility, leggy plants, and increased numbers of maize leaves. This phenomenon severely affects the utilization of tropical maize germplasm resources. The sensitivity to photoperiod is mainly reflected in differences in plant height (PH), ear height (EH), total leaf number (LN), leaf number under ear (LE), silking stage (SS), and anthesis stage (AT) in the same variety under different photoperiod conditions. These differences are more pronounced for varieties that are more sensitive to photoperiod. In the current study, a high-density genetic map was constructed from a recombinant inbred line (RIL) population containing 209 lines to map the quantitative trait loci (QTL) for photoperiod sensitivity of PH, EH, LN, LE, SS, and AT. A total of 39 QTL were identified, including three consistent major QTL. We identified candidate genes in the consensus major QTL region by combined analysis of transcriptome data, and after enrichment by GO and KEGG, we identified a total of four genes (Zm00001d006212, Zm00001d017241, Zm00001d047761, and Zm00001d047632) enriched in the plant circadian rhythm pathway (KEGG:04712). We analyzed the expression levels of these four genes, and the analysis results showed that there were significant differences in response under different photoperiod conditions for three of them (Zm00001d047761, Zm00001d006212 and Zm00001d017241). The results of functional verification showed that the expression patterns of genes rhythmically oscillated, which can affect the length of the hypocotyl and the development of the shoot apical meristem. We also found that the phenotypes of the positive plants were significantly different from the control plants when they overexpressed the objective gene or when it was knocked out, and the expression period, phase, and amplitude of the target gene also shifted. The objective gene changed its own rhythmic oscillation period, phase, and amplitude with the change in the photoperiod, thereby regulating the photoperiod sensitivity of maize. These results deepen our understanding of the genetic structure of photoperiod sensitivity and lay a foundation for further exploration of the regulatory mechanism of photoperiod sensitivity.

Ammonia borane (AB) can be catalytically hydrolyzed to provide hydrogen at room temperature due to its high potentaial for hydrogen storage. Non-precious metal heterogeneous catalysts have broad application in the field of energy catalysis. In this article, catalysts precursor is obtained from Co-Ti-resorcinol-formaldehyde resin by sol–gel method. Co/TiO2@N-C (CTC) catalyst is prepared by calcining the precursor under high temperature conditions in nitrogen atmosphere. Co-CoOx/TiO2@N-C (COTC) is generated by the controllable oxidation reaction of CTC. The catalyst can effectively promote the release of hydrogen during the hydrolytic dehydrogenation of AB. High hydrogen generation at a specific rate of 5905 mL min−1 gCo−1 is achieved at room temperature. The catalyst retains its 85% initial catalytic activity even for its fifth time use in AB hydrolysis. The synergistic effect among Co, Co3O4 and TiO2 promotes the rate limiting step with dissociation and activation of water molecules by reducing its activation energy. The applied method in this study promotes the development of non-precious metals in catalysis for utilization in clean energy sources.

Abstract Long non-coding RNAs (lncRNAs) are non-coding RNAs of more than 200 nucleotides. To date, the roles of lncRNAs in soybean fatty acid synthesis have not been fully studied. Here, the low-linolenic acid mutant ‘MT72′ and the wild-type control ‘JN18′ were used as materials. The lncRNAs in young pods at 30 and 40 days (d) after flowering were systematically identified and analyzed using transcriptome sequencing technology combined with bioinformatics tools. A total of 39,324 lncRNAs and 561 differentially expressed lncRNAs were identified. A lncRNAs-miRNAs-protein-coding genes (mRNAs) network was constructed, and 46 lncRNAs, 46 miRNAs and 137 mRNAs were found to be correlated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of 12 targeted mRNAs in the competing endogenous RNA network showed that these lncRNAs may be involved in the biological processes of fatty acid transport, lipid synthesis and cell division. Finally, the expression levels of differentially expressed lncRNAs, miRNAs and mRNAs were verified using qRT-PCR. The expression patterns of most genes were consistent with the sequencing results. In conclusion, new information was provided for the study of fatty acid synthesis by lncRNAs in young soybean pods.

(1) Corn is the most widely planted food crop, feed crop, and economic crop in the world, and plays an important role in agricultural production and national economy development. The copine gene, also known as the BONZAI gene, encodes a Ca2+-dependent phospholipid membrane binding protein that is widely present in eukaryotes. It has been found that the copine protein is a negative regulator of disease resistance regulation and plays a key role in plants’ disease resistance response. In this study, the Agrobacterium-tumefacien-mediated method was used to successfully obtain T2 generation ZmBON3-gene-overexpressing plants and gene-edited plants. Related phenotypes and molecular identification showed that the disease resistance of overexpression plants was significantly reduced, and the disease resistance of gene-edited plants was significantly increased, which verified that the ZmBON3 gene was a negative regulatory gene. By detecting the physiological indexes related to defense, it was found that the content of H2O2 and the enzyme active water of CAT, POD, SOD, and PAL in ZmBON3-gene-edited plants was higher than those in the control plants and ZmBON3-gene-overexpressing plants, and the content of H2O2 and CAT, POD, and SOD in ZmBON3-gene-overexpressing plants was significantly higher than that in the control plants and ZmBON3-gene-overexpressing plants. The enzyme activity of PAL was the lowest. By detecting the expression of key genes of defense-related signaling pathways, it was found that ZmBON3 may be involved in the related defense processes mediated by the R gene, SA pathway, JA pathway, and ABA pathway. In addition, ZmBON3-geneedited plants showed obvious dwarf phenomenon at the seedling stage, but this did not affect the ear length, axis diameter, ear row number, and grain color.

Maize (Zea mays L.) is a tropical crop, and low temperature has become one of the main abiotic stresses for maize growth and development, affecting many maize growth processes. The main area of maize production in China, Jilin province, often suffers from varying degrees of cold damage in spring, which seriously affects the quality and yield of maize. In the face of global climate change and food security concerns, discovering cold tolerance genes, developing cold tolerance molecular markers, and creating cold-tolerant germplasm have become urgent for improving maize resilience against these conditions and obtaining an increase in overall yield. In this study, whole-genome sequencing and genotyping by sequencing were used to perform genome-wide association analysis (GWAS) and quantitative trait locus (QTL) mapping of the two populations, respectively. Overall, four single-nucleotide polymorphisms (SNPs) and 12 QTLs were found to be significantly associated with cold tolerance. Through joint analysis, an intersection of GWAS and QTL mapping was found on chromosome 3, on which the Zm00001d002729 gene was identified as a potential factor in cold tolerance. We verified the function of this target gene through overexpression, suppression of expression, and genetic transformation into maize. We found that Zm00001d002729 overexpression resulted in better cold tolerance in this crop. The identification of genes associated with cold tolerance contributes to the clarification of the underlying mechanism of this trait in maize and provides a foundation for the adaptation of maize to colder environments in the future, to ensure food security.

Drought stress critically endangers the growth and development of crops. Glutathione S-transferase plays a vital role in response to abiotic stress. However, there are few studies on the role of glutathione S-transferase in maize drought stress. In this study, the significantly downregulated expression of ZmGST26 in roots under drought stress was analyzed by qRT-PCR. Promoter analyses showed that there were several cis-acting elements related to drought stress and that were involved in oxidative response in the promoter region of ZmGST26. Subcellular localization results showed that ZmGST26 was localized in the nucleus. The transgenic lines of the Arabidopsis over-expressing ZmGST26 were more sensitive to drought stress and ABA in seed germination and inhibited ABA-mediated stomatal closure. Under drought stress, phenotypic analyses showed that the germination rate, root length and survival rate of ZmGST26 overexpressing lines were significantly lower than those of wild-type lines. The determination of physiological and biochemical indexes showed that the water loss rate, malondialdehyde, O2− and H2O2 of the overexpression lines significantly increased compared with wild-type Arabidopsis, but the antioxidant enzyme activities (CAT, SOD and POD), and proline and chlorophyll contents were significantly reduced. Subsequently, the qRT-PCR analysis of drought stress-related gene expression showed that, under drought stress conditions, the expression levels of DREB2A, RD29A, RD29B and PP2CA genes in ZmGST26 overexpression lines were significantly lower than those in wild-type Arabidopsis. In summary, ZmGST26 reduced the drought resistance of plants by aggravating the accumulation of reactive oxygen species in Arabidopsis.

Camellia granthamiana is a rare and endangered plant peculiar to China, and a total of 5 plants have been found at present. Based on the next generation sequencing, the whole chloroplast (Cp) genome of (Camellia granthamiana Sealy) of Camellia oleifera was constructed.In this study, the complete chloroplast (cp) genome of Camellia granthamiana was assembled based on next generation sequencing.The cp genome was 157,001 bp in length, including a large single copy (LSC) region of 70,387 bp, a small single copy (SSC) region of 18,296 bp and a pair of inverted repeats (IRs) of 52,082 bp. The genome contained 135 genes, including 90 protein-coding genes, 37 tRNA genes and 8 ribosomal RNA genes. The majority of these gene species occurred as a single copy.

Salix magnifica is only sporadically distributed in the western part of Sichuan, the area of the willows is narrow. There are not many plants, and they easily fall into the endangered state. It is currently on the International Union for Conservation of Nature (IUCN) red list of threatened species. In this study, we first assembled the complete chloroplast (cp) genome of Salix magnifica by Illumina paired-end reads data. The whole genome was 154,977 bp, consisting of a pair of inverted repeats of 27,457 bp, large single-copy region, and a small single-copy region (71,119 and 16,205 bp in length, respectively). The cp genome contained 116 genes, including 80 protein-coding genes and 36 tRNA genes. The overall GC content of the whole genome was 36.7%. A neighbour-joining phylogenetic analysis demonstrated a close relationship between Salix magnifica and Salix oreinoma.

Tree fern Alsophila spinulosa is an endangered relic plant in the world. It is currently on the International Union for Conservation of Nature (IUCN) red list of threatened species. In this study, we first assembled the complete chloroplast (cp) genome of A. spinulosa by Illumina paired-end reads data. The whole genome was 156,661 bp, consisting of a pair of inverted repeats of 24,364 bp, large single copy region and a small single copy region (70,352 and 21,624 bp in length, respectively). The cp genome contained 133 genes, including 92 protein-coding genes, 33 trRNA genes, and eight rRNA genes. The overall GC content of the whole genome was 40.4%. A neighbour-joining phylogenetic analysis demonstrated a close relationship between A. spinulosa and Cystoathyrium chinense Ching.

Davidia involucrata Baill. is a kind of tertiary paleotropical plant floristic relic species unique to China. This rare plant is disappearing due to poor adaptability and serious poaching. We first assembled the complete chloroplast (cp) genome of Davidia involucrata Baill. by Illumina paired-end reads data. The whole genome was 169,085 bp, consisting of a pair of inverted repeats of 169,379 bp, large single copy region and a small single copy region (96,712 and 67,667 bp in length, respectively). The cp genome contained 90 genes, including 64 protein-coding genes, 22 trRNA genes and 4 rRNA genes. The overall GC content of the whole genome was 38.04%. A neighbor-joining phylogenetic analysis demonstrated a close relationship between Davidia involucrata Baill. and Nyssa yunnanensis.

Saussurea involuerata (S. involuerata), a kind of composite and perennial herbage plant, is a rare and precious alpine medicinal plants with high medicinal value, it can regulate human’s body and has health care function, therefore attracts attention of many scholars. It is currently on the International Union for Conservation of Nature (IUCN) red list of threatened species. In this study, we first assembled the complete chloroplast (cp) genome of S. involucrata by Illumina paired-end reads data. The whole genome was 152,490 bp, consisting of a pair of inverted repeats of 69,041 bp, large and small single-copy regions of 69,045bp and 18,638 bp in length, respectively. The cp genome contained 134 genes, including 90 protein-coding genes, 36 tRNA genes, and 8 rRNA genes. The overall GC content of the whole genome was 37.7%. A neighbor-joining phylogenetic analysis demonstrated a close relationship between S. involuerata and Arctium lappa.

Ginkgo biloba L. is the oldest relict plant among the gymnosperms, left after the quaternary glacial movement. There are few living G. biloba and few old trees over a hundred years old. It is currently on the International Union for Conservation of Nature (IUCN) red list of threatened species. In this study, we first assembled the complete chloroplast (cp) genome of G. biloba L. by Illumina paired-end reads data. The whole genome was 156,988 bp, consisting of a pair of inverted repeats of 34,056 bp, large and small single copy regions of 56,819 and 22,763 bp in length, respectively. The cp genome contained 131 genes, including 84 protein-coding genes, 31 trRNA genes and 5 rRNA genes. The overall GC content of the whole genome was 39.6%. A neighbour-joining phylogenetic analysis demonstrated a close relationship between G. biloba L. and Cycas revoluta.

PCR detection, quantitative real-time PCR (q-RTPCR), outdoor insect resistance, and disease resistance identification were carried out for the detection of genetic stability and disease resistance through generations (T2, T3, and T4) in transgenic maize germplasms (S3002 and 349) containing the bivalent genes (insect resistance gene Cry1Ab13-1 and disease resistance gene NPR1) and their corresponding wild type. Results indicated that the target genes Cry1Ab13-1 and NPR1 were successfully transferred into both germplasms through tested generations; qPCR confirmed the expression of Cry1Ab13-1 and NPR1 genes in roots, stems, and leaves of tested maize plants. In addition, S3002 and 349 bivalent gene-transformed lines exhibited resistance to large leaf spots and corn borer in the field evaluation compared to the wild type. Our study confirmed that Cry1Ab13-1 and NPR1 bivalent genes enhanced the resistance against maize borer and large leaf spot disease and can stably inherit. These findings could be exploited for improving other cultivated maize varieties. [ABSTRACT FROM AUTHOR]

The embryos of maize (Zea mays L.) inbred lines GS02, GS07, GS08, GS11 and GS15 were used as receptor materials to optimize the receptor system from the aspects of genotype, medium components and stress (PEG6000, mannitol, salt and low phosphorus). The results showed that GS07 had the highest induction rate (95.2%). Orthogonal test analysis showed that the best combination of medium components in induction was A2B3C1D3(2), namely, the concentration of 2, 4-dichlorophenoxy acetic acid (2,4-D) was 4 mg·mL-1, the concentration of L-Proline (L-Pro) was 0.8 mg·mL-1, and the concentration of silver nitrate (AgNO3) was 10 mg·mL-1 (or 5 mg·mL). Interestingly, we found that the optimal medium supplemented with 30 g·L-1 PEG6000 or 80 g·L-1 mannitol was suitable for antioxidant enzyme activity and malondialdehyde (MDA) content in GS07 callus. Exogenous 10 mmol·L-1 Ca2+ in the medium components with 100 mmol·L-1 sodium chloride (NaCl) could improve the activity of antioxidant enzymes in GS07 callus. Callus of GS07 could divide normally and grow well in medium components with 27 mg·L-1 KH2PO4. This study enhanced the adaptability of maize callus to stress and optimized the culture conditions. [ABSTRACT FROM AUTHOR]

To develop cold-tolerant maize germplasms and identify the activation of INDUCER OF CRT/DRE-BINDING FACTOR EXPRESSION (ICE1) expression in response to cold stress, RT-PCR was used to amplify the complete open reading frame sequence of the ICE1 gene and construct the plant expression vector pCAMBIA3301-ICE1-Bar. Immature maize embryos and calli were transformed with the recombinant vector using Agrobacterium tumefaciens-mediated transformations. From the regenerated plantlets, three T1 lines were screened and identified by PCR. A Southern blot analysis showed that a single copy of the ICE1 gene was integrated into the maize (Zea mays L.) genomes of the three T1 generations. Under low temperature-stress conditions (4°C), the relative conductivity levels decreased by 27.51%-31.44%, the proline concentrations increased by 12.50%-17.50%, the malondialdehyde concentrations decreased by 16.78%-18.37%, and the peroxidase activities increased by 19.60%-22.89% in the T1 lines compared with those of the control. A real-time quantitative PCR analysis showed that the ICE1 gene was ectopically expressed in the roots, stems, and leaves of the T1 lines. ICE1 positively regulates the expression of the CBF genes in response to cold stress. Thus, this study showed the successful transformation of maize with the ICE1 gene, resulting in the generation of a new maize germplasm that had increased tolerance to cold stress. [ABSTRACT FROM AUTHOR]

Exploring the molecular mechanism of soybean response to drought stress, providing a basis for genetic improvement and breeding of heat-resistant varieties, relying on the transcriptome sequencing data of unpollinated ovary at the seven-leaf stage of soybean Jinong 18(JN18) and Jinong 18 mutant (JB18) soybeans, using reverse transcription, one gene in the sHSP family was cloned using PCR (RT-PCR) and it was named sHSP26. In this experiment, the soybean sHSP26 gene was successfully cloned by RT-PCR, the protein encoded by the sHSP26 gene was analyzed by bioinformatics, and the sHSP26 gene overexpression vector and CRISPR/Cas9 gene-editing vector were constructed. The positive plants were derived from Agrobacterium-mediated transformation of soybean cotyledon nodes, and T2 plants were identified through conventional PCR, QT-PCR, and Southern blot hybridization. Finally, through the determination of drought-related physiological and biochemical indicators and the analysis of agronomic traits, further research on gene function was conducted. The results indicated that the overexpression vector plant GmsHSP26 gene expression increased. After stress, the SOD and POD activities, and the PRO content of the transgenic overexpression plants increased, while the MDA content decreased. The reverse was true for soybean plants with genetically modified editing vectors. A survey of agronomic traits indicated that the fourpod ratio and yield per plant of the transgenic overexpression plants were higher than those of the control and transgenic editing vector soybean plants. It indicates that the expression of the sHSP26 gene can enhance drought resistance and soybean yield. The soybean sHSP26 gene cloning and its functional verification have not yet been reported. This is the first report where PCR amplification of soybean sHSP26 genes and gene expression vector were applied. It lays the foundation for creating new drought-resistant transgenic soybean lines through genetic engineering technology and is essential for improving soybean yield and quality. [ABSTRACT FROM AUTHOR]

Seed shattering refers to the phenomenon in which the pods split along the abdominal and back sutures before the crop is received, so that the seeds are spread. Seed shattering is vital to the reproduction of their offspring in wild plants, but it is also the main cause of crop yield loss reason. Pod-explosion resistance is a complex process of physical and physiological and biochemical reactions. Soybean seed shattering phenomenon is widespread, which severely restricts the development of soybean industry. Seed shattering (pod cracking or fruit dropping) is essential for the reproduction of its offspring in wild plants, but it is also the main cause of crop yield loss. This article analyzes the morphology and structure of pods related to seed shattering from the morphology of pods. On the basis of the regularity of the occurrence of seed shattering and the summary of phenotypic index identification methods, physiologically introduced the regulation mechanism of key enzymes and endogenous hormones on seed shattering. The localization, labeling and cloning of seed shattering genes are introduced in molecular biology. The study focused on reviewing the latest advances in the research on soybean seed shattering characteristics, and discussed with the research results of related crops. Finally, the research and application of soybean seed shattering resistance were prospected for several aspects. [ABSTRACT FROM AUTHOR]

Maize flowering is an important agronomic character, which is controlled by quantitative trait loci (QTL). Over the years, a large number of flowering-related QTL have been found in maize and exist in public databases. However, combining these data, re-analyzing and mining candidate loci and fine mapping of flowering-related traits to reduce confidence intervals has become a hot issue in maize. In this study, the QTL of 6 important agronomic traits of maize flowering were collected from 15 published articles, including flowering period (DA), Days to tasseling (DTT), Days to silking (DS), Days to pollen shedding (DTP), anthesis-silking interval (ASI) and the photosensitive (PS). Through meta-analysis, 622 QTL were integrated into 26 meta-QTLs (MQTL). Finally, the candidate genes related to maize flowering (Gene IDs: ZM00001D005791, ZM00001D019045, ZM00001D050697, ZM00001D011139) were identified by Gene Ontology (GO) enrichment and hierarchical cluster analysis of expression profile. Based on the results of this study, the genetic characteristics of maize flowering traits will be further analyzed, which is of great significance to guide the improvement of important agronomic characters and improve the efficiency of breeding. [ABSTRACT FROM AUTHOR]

Soybean (Glycine max (L.) Merr.) is an important cultivated crop, which requires much water during its growth, and drought seriously affects soybean yields. Studies have shown that the expression of small heat shock proteins can enhance drought resistance, cold resistance and salt resistance of plants. In this experiment, soybean GmHsps_p23-like gene was successfully cloned by RT-PCR, the protein encoded by the GmHsps_p23-like gene was subjected to bioinformatics analysis, and the pCAMBIA3301-GmHsps_p23-like overexpression vector and pCBSG015-GmHsps_p23-like gene editing vector were constructed. Agrobacterium-mediated method was used to transform soybeans to obtain positive plants. RT-PCR detection, rehydration experiment and drought resistance physiological and biochemical index detection were performed on the T2 generation positive transgenic soybean plants identified by PCR and Southern hybridization. The results showed that the overexpression vector plant GmHsps_p23-like gene expression increased. After rehydration, the transgenic overexpression plants returned to normal growth, and the damage to the plants was low. After drought stress, the SOD and POD activities and the PRO content of the transgenic overexpression plants increased, while the MDA content decreased. The reverse was true for soybean plants with genetically modified editing vectors. The drought resistance of the overexpressed soybeans under drought stress was higher than that of the control group, and had a stronger drought resistance. It showed that the expression of soybean GmHsps_p23-like gene can improve the drought resistance of soybean. The cloning and functional verification of soybean GmHsps_p23-like gene had not been reported yet. This is the first time that PCR technology has been used to amplify the soybean GmHsps_p23-like gene and construct an expression vector for this gene. This research has laid the foundation for transgenic technology to improve plant drought resistance and cultivate new drought-resistant transgenic soybean varieties. [ABSTRACT FROM AUTHOR]