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<jats:p><jats:italic>Eremosparton songoricum</jats:italic> (Litv.) Vass. is a rare leafless legume shrub endemic to central Asia which grows on bare sand. It shows extreme drought tolerance and is being developed as a model organism for investigating morphological, physiological, and molecular adaptations to harsh desert environments. APETALA2/Ethylene Responsive Factor (AP2/ERF) is a large plant transcription factor family that plays important roles in plant responses to various biotic and abiotic stresses and has been extensively studied in several plants. However, our knowledge on the AP2/ERF family in legume species is limited, and no respective study was conducted so far on the desert shrubby legume <jats:italic>E. songoricum</jats:italic>. Here, 153 <jats:italic>AP2/ERF</jats:italic> genes were identified based on the <jats:italic>E. songoricum</jats:italic> genome data. <jats:italic>EsAP2/ERFs</jats:italic> covered <jats:italic>AP2</jats:italic> (24 genes), <jats:italic>DREB</jats:italic> (59 genes), <jats:italic>ERF</jats:italic> (68 genes), and <jats:italic>Soloist</jats:italic> (2 genes) subfamilies, and lacked canonical <jats:italic>RAV</jats:italic> subfamily genes based on the widely used classification method. The <jats:italic>DREB</jats:italic> and <jats:italic>ERF</jats:italic> subfamilies were further divided into A1–A6 and B1–B6 groups, respectively. Protein motifs and exon-intron structures of <jats:italic>EsAP2/ERFs</jats:italic> were also examined, which matched the subfamily/group classification. <jats:italic>Cis</jats:italic>-acting element analysis suggested that <jats:italic>EsAP2/ERF</jats:italic> genes shared many stress- and hormone-related <jats:italic>cis</jats:italic>-regulatory elements. Moreover, the gene numbers and the ratio of each subfamily and the intron-exon structures were systematically compared with other model plants ranging from algae to angiosperms, including ten legumes. Our results supported the view that <jats:italic>AP2</jats:italic> and <jats:italic>ERF</jats:italic> evolved early and already existed in algae, whereas <jats:italic>RAV</jats:italic> and <jats:italic>DREB</jats:italic> began to appear in moss species. Almost all plant <jats:italic>AP2</jats:italic> and <jats:italic>Soloist</jats:italic> genes contained introns, whereas most <jats:italic>DREB</jats:italic> and <jats:italic>ERF</jats:italic> genes did not. The majority of <jats:italic>EsAP2/ERFs</jats:italic> were induced by drought stress based on RNA-seq data, <jats:italic>EsDREBs</jats:italic> were highly induced and had the largest number of differentially expressed genes in response to drought. Eight out of twelve representative <jats:italic>EsAP2/ERFs</jats:italic> were significantly up-regulated as assessed by RT-qPCR. This study provides detailed insights into the classification, gene structure, motifs, chromosome distribution, and gene expression of <jats:italic>AP2/ERF</jats:italic> genes in <jats:italic>E. songoricum</jats:italic> and lays a foundation for better understanding of drought stress tolerance mechanisms in legume plants. Moreover, candidate genes for drought-resistant plant breeding are proposed.</jats:p>

<jats:p>The present study aimed to explore the antibacterial activity of various organic root extracts of <jats:italic>Skimmia anquetilia</jats:italic> N.P. Taylor and Airy Shaw and the identification of major functional groups and phytoconstituents through fourier transform infrared spectrometer (FTIR) and gas chromatography-mass spectrometer (GC-MS). The extracts were evaluated for antibacterial activity against multidrug-resistant (MDR) strains <jats:italic>viz</jats:italic>., <jats:italic>Pseudomonas aeruginosa</jats:italic> (MTCC424), <jats:italic>Escherichia coli</jats:italic> (MTCC739), <jats:italic>Klebsiella pneumoniae</jats:italic> (MTCC139), <jats:italic>Salmonella typhi</jats:italic> (MTCC3224), and <jats:italic>Staphylococcus aureus</jats:italic> (MTCC96). ESKAPE pathogens such as <jats:italic>S. aureus</jats:italic>, <jats:italic>K. pneumoniae</jats:italic>, and <jats:italic>P. aeruginosa</jats:italic> are responsible for a majority of all healthcare acquired infections. The ethyl acetate extract showed the highest zone of inhibition against <jats:italic>P. aeruginosa</jats:italic> (18 mm) followed by <jats:italic>S. aureus</jats:italic> (17 mm). The minimum inhibitory concentration (MIC) of ethyl acetate extract against strain of <jats:italic>S. aureus</jats:italic> (4 mg mL<jats:sup>–1</jats:sup>) demonstrated therapeutically significant antibacterial activity. The FTIR spectra of root extracts revealed the occurrence of functional characteristic peaks of alcohols, carboxylic acids, aromatic compounds, alkanes, alkenes, and amines that indicates the presence of various metabolites in the extracts. The GC-MS investigation led to the identification of diverse phytoconstituents in each of the extracts with varying concentrations and molecular masses. The highest number of compounds were identified from the methanol extract (112), followed by <jats:italic>n</jats:italic>-hexane extract (88) and ethyl acetate extract (74). The most predominant compounds were 5, 10-pentadecadien-1-ol, (<jats:italic>Z,Z</jats:italic>)-(33.94%), <jats:italic>n</jats:italic>-hexadecanoic acid (13.41%) in <jats:italic>n</jats:italic>-hexane extract, 5,10-pentadecadien-1-ol, (<jats:italic>Z,Z</jats:italic>)-(10.48%), 1-hexyl-2-nitrocyclohexane (7.94%) in ethyl acetate extract, and 1-hexyl-2-nitrocyclohexane (15.43%), <jats:italic>cis,cis,cis-</jats:italic>7,10,13-hexadecatrienal (13.29%) in methanol extract. The results of the present study will create a way for the invention of plant-based medicines for various life-threatening microbial infections using <jats:italic>S. anquetilia</jats:italic>, which may lead to the development of novel drugs against drug-resistant microbial infections.</jats:p>

<jats:p>We aimed to efficiently enhance plant Hg(II) tolerance by the transgenic approach utilizing a bacterial mercury transporter MerC, an Arabidopsis mesophyll specific promoter <jats:italic>pRBCS1A</jats:italic>, and a vacuolar membrane targeting syntaxin AtVAM3/SYP22. We generated two independent homozygous Arabidopsis pRBCS1A-TCV lines expressing <jats:italic>mT-Sapphire-MerC-AtVAM3</jats:italic> under the control of <jats:italic>pRBCS1A</jats:italic>. Quantitative RT-PCR showed that the transgene was expressed specifically in shoots of pRBCS1A-TCV lines. Confocal analyses further demonstrated the leaf mesophyll specific expression of mT-Sapphire-MerC-AtVAM3. Confocal observation of the protoplast derived from the F1 plants of the pRBCS1A-TCV line and the tonoplast marker line p35S-GFP-δTIP showed the tonoplast colocalization of mT-Sapphire-MerC-AtVAM3 and GFP-δTIP. These results clearly demonstrated that mT-Sapphire-MerC-AtVAM3 expression in Arabidopsis is spatially regulated as designed at the transcript and the membrane trafficking levels. We then examined the Hg(II) tolerance of the pRBCS1A-TCV lines as well as the p35S-driven MerC-AtVAM3 expressing line p35S-CV under the various Hg(II) stress conditions. Short-term (12 d) Hg(II) treatment indicated the enhanced Hg(II) tolerance of both pRBCS1A-TCV and p35S-CV lines. The longer (3 weeks) Hg(II) treatment highlighted the better shoot growth of the transgenic plants compared to the wild-type Col-0 and the pRBCS1A-TCV lines were more tolerant to Hg(II) stress than the p35S-CV line. These results suggest that mesophyll-specific expression of MerC-AtVAM3 is sufficient or even better to enhance the Arabidopsis Hg(II) tolerance. The Hg accumulation in roots and shoots did not differ between the wild-type Col-0 and the MerC-AtVAM3 expressing plants, suggesting that the boosted Hg(II) tolerance of the transgenic lines would be attributed to vacuolar Hg-sequestration by the tonoplast-localized MerC. Further perspectives of the MerC-based plant engineering are also discussed.</jats:p>

<jats:p><jats:italic>Castanopsis hystrix</jats:italic> is one of the main timber trees grown in China. However, severe shortage of natural seeds and the difficulty of explant regeneration has limited seedling supply. As such, there is a need for research on asexual multiplication of <jats:italic>C. hystrix</jats:italic>. This study established a rapid propagation technology system for <jats:italic>C. hystrix</jats:italic> genotypes, including explant treatment, proliferation, and rooting. HZ (a modified MS medium) supplemented with 4.4 μM BA and 0.5 μM IBA was found to be the optimal medium for shoot sprouting. The maximum proliferation coefficient and the number of effective shoots was obtained on HZ medium supplemented with 2.6 μM BA and 1.0 μM IBA, were 3.00 and 5.63, respectively. A rooting rate of 83.33% was achieved using half-strength HZ medium supplemented with 3.2 μM NAA. Adding vitamin C (80 mg⋅l<jats:sup>–1</jats:sup>) for 7 days in a dark environment reduced the browning rate, while increasing the proliferation rate. Additionally, through cytological observation, we established how and where adventitious roots occur. The survival rate of transplanted plantlets was &amp;gt; 90%. This is the first report of an <jats:italic>in vitro</jats:italic> regeneration technique that uses stem segments of mature <jats:italic>C. hystrix</jats:italic> as explants.</jats:p>

<jats:p>Proper timing of flowering, a phase transition from vegetative to reproductive development, is crucial for plant fitness. The floral repressor <jats:italic>FLOWERING LOCUS C</jats:italic> (<jats:italic>FLC</jats:italic>) is the major determinant of flowering in <jats:italic>Arabidopsis thaliana</jats:italic>. In rapid-cycling <jats:italic>A. thaliana</jats:italic> accessions, which bloom rapidly, <jats:italic>FLC</jats:italic> is constitutively repressed by autonomous pathway (AP) genes, regardless of photoperiod. Diverse AP genes have been identified over the past two decades, and most of them repress <jats:italic>FLC</jats:italic> through histone modifications. However, the detailed mechanism underlying such modifications remains unclear. Several recent studies have revealed novel mechanisms to control <jats:italic>FLC</jats:italic> repression in concert with histone modifications. This review summarizes the latest advances in understanding the novel mechanisms by which AP proteins regulate <jats:italic>FLC</jats:italic> repression, including changes in chromatin architecture, RNA polymerase pausing, and liquid–liquid phase separation- and ncRNA-mediated gene silencing. Furthermore, we discuss how each mechanism is coupled with histone modifications in <jats:italic>FLC</jats:italic> chromatin.</jats:p>

<jats:p><jats:italic>Codonopsis tangshen</jats:italic> Oliv (<jats:italic>C. tangshen</jats:italic>) is an important Chinese traditional medicinal plant with various health benefits. However, the growth of <jats:italic>C. tangshen</jats:italic> are seriously affected by continuous cropping, which led to the decrease of the yield and quality. A field experiment was conducted to learn the effects of soil amendments on the growth of <jats:italic>C. tangshen</jats:italic> under continuous cropping condition, and the biological events which occurred at molecular level were investigated. The results indicated that the content of chlorophyll a (Chl a), chlorophyll b (Chl b), and carotenoid (Car) was significantly higher in SCPM (silicon-calcium-potassium-magnesium fertilizer), SCPMA (SCPM combined with azoxystrobin) and SCPMAOM (SCPM combined with azoxystrobin and organic manure) treatments. Moreover, the yield and the levels of alkaloid, polysaccharide, flavone and total protein in the treatments of SCPM, SCPMA and SCPMAOM were significantly higher than those in the control, and these indexes were all highest in the SCPMAOM treatment. RNA-sequencing (RNA-Seq) is an economical and efficient method to obtain genetic information for species with or without available genome data. In this study, RNA-Seq was performed to understand how continuously cropped <jats:italic>C. tangshen</jats:italic> responded to the soil amendments at the transcriptome level. The number of differentially expressed genes (DEGs) were as follows: CK vs. SCPM (719 up- and 1456 down-), CK vs. SCPMA (1302 up- and 1748 down-), CK vs. SCPMAOM (1274 up- and 1678 down-). The soil amendments affected the growth of <jats:italic>C. tangshen</jats:italic> mainly by regulating the genes involved in pathways of ‘photosynthesis,’ ‘plant hormone signal transduction,’ ‘biosynthesis of unsaturated fatty acids,’ ‘phenylpropanoid biosynthesis,’ and ‘starch and sucrose metabolism,’ etc. qRT-PCR was performed to validate the expressions of 10 target genes such as <jats:italic>CP26</jats:italic>, <jats:italic>PsaF</jats:italic>, and <jats:italic>POX</jats:italic>, etc., which verified the reliability of RNA-Seq results. Overall, this study revealed the roles and underlying mechanisms of the soil amendments in regulating the growth of continuously cropped <jats:italic>C. tangshen</jats:italic> at transcriptome level. These findings are beneficial for improving the continuous cropping tolerance and may be valuable for future genetic improvement of <jats:italic>C. tangshen</jats:italic>.</jats:p>

<jats:p>Heat and Water Deficit Stress (WDS) tend to impede and restrict the efficiency of photosynthesis, chlorophyll fluorescence, and maximum photochemical quantum yield in plants based on their characteristic ability to interfere with the electron transport system in photosystem II. Dissection of the electron transport pathway in Photosystem II (PSII) under water deficit and Heat Stress (HS) can be insightful in gaining knowledge on the various attributes of the photosynthetic performance of a plant. We attempt a high-resolution dissection of electron transport in PSII with studies on chlorophyll a fast fluorescence kinetics and non-photochemical quenching (NPQ) as a response to and recovery from these stresses in pearl millet [<jats:italic>Pennisetum glaucum</jats:italic> (L.) R. Br.] in isolation and combination. In this study, we bring out the mechanisms by which both heat and water stress, in isolation and in combination, affect the photosynthetic electron transport in Photosystem II. Our results indicate that oxygen evolution complex (OEC) damage is the primary effect of heat stress and is not seen with the same intensity in the water-stressed plants. Low exciton absorption flux in heat stress and combined stress was seen due to OEC damage, and this caused an electron transport traffic jam in the donor side of PS II. Both the specific energy flux model and the phenomenological flux model developed from the derived values in our study show that water deficit stress in combination with heat stress has a much stronger effect than the stresses in isolation on the overall electron transport pathway of the PS II in pearl millet plants.</jats:p>

<jats:p>The ever-changing climate and the current COVID-19 pandemic compound the problems and seriously impact agriculture production, resulting in socio-economic insecurities and imposing health implications globally. Most of the poor and malnourished population in the developing countries depends on agriculture for food, income, and employment. Impact of climate change together with the COVID-19 outbreak revealed immense problems highlighting the importance of mainstreaming climate-resilient and low input crops with more contemporary agriculture practices. Orphan millets play a vital role in the poor and malnourished population's livelihood, food and nutrition security. Recognizing their unique potential, the United Nations-Food and Agriculture Organization has announced the year 2023 as the “International Year of Millets”. However, despite the unique properties for present and future agriculture of orphan millets, their cultivation is declining in many countries. As a result, millets have gained attention from researchers which eventually decelerated “multi-omics” resource generation. This review summarizes the benefits of millets and major barriers/ bottlenecks in their improvement. We also discuss the pre- and post-harvest technologies; policies required to introduce and establish millets in mainstream agriculture. To improve and ensure the livelihood of the poor/malnourished population, intensive efforts are urgently needed in advancing the research and development, implementing pre- and post-harvest technological intervention strategies, and making favorable policies for orphan crops to accomplish food and nutrition security. National and international collaborations are also indispensable to address the uncertain effects of climate change and COVID-19.</jats:p>

<jats:p>Cucumber is an important vegetable in China, and its yield and cultivation area are among the largest in the world. Excessive temperatures lead to high-temperature disorder in cucumber. Heat shock protein 20 (HSP20), an essential protein in the process of plant growth and development, is a universal protective protein with stress resistance. HSP20 plays crucial roles in plants under stress. In this study, we characterized the <jats:italic>HSP20</jats:italic> gene family in cucumber by studying chromosome location, gene duplication, phylogenetic relationships, gene structure, conserved motifs, protein-protein interaction (PPI) network, and <jats:italic>cis</jats:italic>-regulatory elements. A total of 30 <jats:italic>CsHSP20</jats:italic> genes were identified, distributed across 6 chromosomes, and classified into 11 distinct subgroups based on conserved motif composition, gene structure analyses, and phylogenetic relationships. According to the synteny analysis, cucumber had a closer relationship with <jats:italic>Arabidopsis</jats:italic> and soybean than with rice and maize. Collinearity analysis revealed that gene duplication, including tandem and segmental duplication, occurred as a result of positive selection and purifying selection. Promoter analysis showed that the putative promoters of <jats:italic>CsHSP20</jats:italic> genes contained growth, stress, and hormone <jats:italic>cis</jats:italic>-elements, which were combined with protein-protein interaction networks to reveal their potential function mechanism. We further analyzed the gene expression of <jats:italic>CsHSP20</jats:italic> genes under high stress and found that the majority of the <jats:italic>CsHSP20</jats:italic> genes were upregulated, suggesting that these genes played a positive role in the heat stress-mediated pathway at the seedling stage. These results provide comprehensive information on the <jats:italic>CsHSP20</jats:italic> gene family in cucumber and lay a solid foundation for elucidating the biological functions of CsHSP20. This study also provides valuable information on the regulation mechanism of the <jats:italic>CsHSP20</jats:italic> gene family in the high-temperature resistance of cucumber.</jats:p>

<jats:p>China is known for its abundant plant resources, but biodiversity conservation faces unprecedented challenges. To provide feasible suggestions for sustainable conservation, we used the species richness algorithm and complementary algorithm to study distribution patterns of 34,082 seed plants based on 1,007,196 county-level distribution records. We reconstructed a phylogenetic tree for 95.35% of species and estimated the spatial phylogenetics, followed by correlation analyses between different distribution patterns. We identified 264 counties concentrated in southern and south-western mountainous areas as hotspots which covered 10% of the land area of China and harbored 85.22% of the Chinese seed plant species. The biodiversity conservation priorities we identified were highly representative as we have considered multiple conservation indicators. We evaluated the conservation effectiveness and gaps in the network of nature reserves and identified 31.44, 32.95, and 9.47%, respectively, of the hotspot counties as gaps in the national nature reserves, provincial nature reserves and both together, with respectively 55.77, 61.53, and 28.94% of the species. Analysis of the species composition showed there were a large number of threatened and endemic species occurring in the nature reserves’ gaps. The conservation gaps need to be filled by establishing new nature reserves or national parks, especially in south-western China, and more attentions should be paid to strengthen the conservation of specific plant taxa due to the apparent mismatches between different distribution patterns.</jats:p>