Noncanonical usage of stop codons in ciliates expands proteins with structurally flexible Q-rich motifs.

Serine(S)/threonine(T)-glutamine(Q) cluster domains (SCDs), polyglutamine (polyQ) tracts and polyglutamine/asparagine (polyQ/N) tracts are Q-rich motifs found in many proteins. SCDs often are intrinsically disordered regions that mediate protein phosphorylation and protein-protein interactions. PolyQ and polyQ/N tracts are structurally flexible sequences that trigger protein aggregation. We report that due to their high percentages of STQ or STQN amino acid content, four SCDs and three prion-causing Q/N-rich motifs of yeast proteins possess autonomous protein expression-enhancing activities. Since these Q-rich motifs can endow proteins with structural and functional plasticity, we suggest that they represent useful toolkits for evolutionary novelty. Comparative Gene Ontology (GO) analyses of the near-complete proteomes of 26 representative model eukaryotes reveal that Q-rich motifs prevail in proteins involved in specialized biological processes, including Saccharomyces cerevisiae RNA-mediated transposition and pseudohyphal growth, Candida albicans filamentous growth, ciliate peptidyl-glutamic acid modification and microtubule-based movement, Tetrahymena thermophila xylan catabolism and meiosis, Dictyostelium discoideum development and sexual cycles, Plasmodium falciparum infection, and the nervous systems of Drosophila melanogaster, Mus musculus and Homo sapiens. We also show that Q-rich-motif proteins are expanded massively in 10 ciliates with reassigned TAAQ and TAGQ codons. Notably, the usage frequency of CAGQ is much lower in ciliates with reassigned TAAQ and TAGQ codons than in organisms with expanded and unstable Q runs (e.g. D. melanogaster and H. sapiens), indicating that the use of noncanonical stop codons in ciliates may have coevolved with codon usage biases to avoid triplet repeat disorders mediated by CAG/GTC replication slippage.

Extra- and intranuclear heat perception and triggering mechanisms in plants.

The escalating impact of global warming on crop yield and quality poses a significant threat to future food supplies. Breeding heat-resistant crop varieties holds promise, but necessitates a deeper understanding of the molecular mechanisms underlying plant heat tolerance. Recent studies have shed light on the initial events of heat perception in plants. In this review, we provide a comprehensive summary of the recent progress made in unraveling the mechanisms of heat perception and response in plants. Calcium ion (Ca2+), hydrogen peroxide (H2O2), and nitric oxide (NO) have emerged as key participants in heat perception. Furthermore, we discuss the potential roles of the NAC transcription factor NTL3, thermo-tolerance 3.1 (TT3.1), and Target of temperature 3 (TOT3) as thermosensors associated with the plasma membrane. Additionally, we explore the involvement of cytoplasmic HISTONE DEACETYLASE 9 (HDA9), mRNA encoding the phytochrome-interacting factor 7 (PIF7), and chloroplasts in mediating heat perception. This review also highlights the role of intranuclear transcriptional condensates formed by phytochrome B (phyB), EARLY FLOWERING 3 (ELF3), and guanylate-binding protein (GBP)-like GTPase 3 (GBPL3) in heat perception. Finally, we raise the unresolved questions in the field of heat perception that require further investigation in the future.

Automatic identification method of bridge structure damage area based on digital image.

It is of great scientific and practical value to use effective technical means to monitor and warn the structural damage of bridges in real time and for a long time. Traditional image recognition network models are often limited by the lack of on-site images. In order to solve the problem of automatic recognition and parameter acquisition in digital images of bridge structures in the absence of data information, this paper proposes an automatic identification method for bridge structure damage areas based on digital images, which effectively achieves contour carving and quantitative characterization of bridge structure damage areas. Firstly, the digital image features of the bridge structure damage area are defined. By making full use of the feature that the pixel value of the damaged area is obviously different from that of the surrounding image, an image pre-processing method of the structure damaged area that can effectively improve the quality of the field shot image is proposed. Then, an improved Ostu method is proposed to organically fuse the global and local threshold features of the image to achieve the damaged area contour carving of the bridge structure surface image. The scale of damage area, the proportion of damage area and the calculation rule of damage area orientation are constructed. The key inspection and characteristic parameter diagnosis of bridge structure damage area are realized. Finally, test and analysis are carried out in combination with an actual project case. The results show that the method proposed in this paper is feasible and stable, which can improve the damage area measurement accuracy of the current bridge structure. The method can provide more data support for the detection and maintenance of the bridge structure.

Growth of tomato and cucumber seedlings under different light environments and their development after transplanting.

Selecting suitable light conditions according to the plant growth characteristics is one of the important approaches to cultivating high-quality vegetable seedlings. To determine the more favorable LED light conditions for producing high-quality tomato and cucumber seedlings in plant factories with artificial light (PFALS), the growth characteristics of tomato and cucumber seedlings under seven LED light environments (CK, B, UV-A, FR, B+UV-A, UV-A+FR, and B+FR) and the development of these seedlings after transplanting into a plastic greenhouse were investigated. The results showed that the seedling height and hypocotyl length increased in treatments with far-red light supplementation (FR, UV-A+FR, and B+FR), but decreased in the B treatment, in both varieties. The seedling index of tomato seedlings increased in the B+UV-A treatment, while that of cucumber seedlings increased in the FR treatment. After transplanting into a plastic greenhouse, tomato plants that radiated with UV-A had greater flower numbers on the 15th day after transplanting. In cucumber plants of the FR treatment, the flowering time was significantly delayed, and the female flower exhibited at a lower node position. By using a comprehensive scoring analysis of all detected indicators, light environments with UV-A and FR were more beneficial for improving the overall quality of tomato and cucumber seedlings, respectively.

Omics Analysis Unveils the Pathway Involved in the Anthocyanin Biosynthesis in Tomato Seedling and Fruits.

The purple tomato variety 'Indigo Rose' (InR) is favored due to its bright appearance, abundant anthocyanins and outstanding antioxidant capacity. SlHY5 is associated with anthocyanin biosynthesis in 'Indigo Rose' plants. However, residual anthocyanins still present in Slhy5 seedlings and fruit peel indicated there was an anthocyanin induction pathway that is independent of HY5 in plants. The molecular mechanism of anthocyanins formation in 'Indigo Rose' and Slhy5 mutants is unclear. In this study, we performed omics analysis to clarify the regulatory network underlying anthocyanin biosynthesis in seedling and fruit peel of 'Indigo Rose' and Slhy5 mutant. Results showed that the total amount of anthocyanins in both seedling and fruit of InR was significantly higher than those in the Slhy5 mutant, and most genes associated with anthocyanin biosynthesis exhibited higher expression levels in InR, suggesting that SlHY5 play pivotal roles in flavonoid biosynthesis both in tomato seedlings and fruit. Yeast two-hybrid (Y2H) results revealed that SlBBX24 physically interacts with SlAN2-like and SlAN2, while SlWRKY44 could interact with SlAN11 protein. Unexpectedly, both SlPIF1 and SlPIF3 were found to interact with SlBBX24, SlAN1 and SlJAF13 by yeast two-hybrid assay. Suppression of SlBBX24 by virus-induced gene silencing (VIGS) retarded the purple coloration of the fruit peel, indicating an important role of SlBBX24 in the regulation of anthocyanin accumulation. These results deepen the understanding of purple color formation in tomato seedlings and fruits in an HY5-dependent or independent manner via excavating the genes involved in anthocyanin biosynthesis based on omics analysis.

Far-Red-Light-Induced Morphology Changes, Phytohormone, and Transcriptome Reprogramming of Chinese Kale (Brassica alboglabra Bailey).

With far-red-light supplementation (3 W·m-2, and 6 W·m-2), the flower budding rate, plant height, internode length, plant display, and stem diameter of Chinese kale were largely elevated, as well as the leaf morphology such as leaf length, leaf width, petiole length, and leaf area. Consequently, the fresh weight and dry weight of the edible parts of Chinese kale were markedly increased. The photosynthetic traits were enhanced, and the mineral elements were accumulated. To further explore the mechanism that far-red light simultaneously promoted the vegetative growth and reproductive growth of Chinese kale, this study used RNA sequencing to gain a global perspective on the transcriptional regulation, combining it with an analysis of composition and content of phytohormones. A total of 1409 differentially expressed genes were identified, involved mainly in pathways related to photosynthesis, plant circadian rhythm, plant hormone biosynthesis, and signal transduction. The gibberellins GA9, GA19, and GA20 and the auxin ME-IAA were strongly accumulated under far-red light. However, the contents of the gibberellins GA4 and GA24, the cytokinins IP and cZ, and the jasmonate JA were significantly reduced by far-red light. The results indicated that the supplementary far-red light can be a useful tool to regulate the vegetative architecture, elevate the density of cultivation, enhance the photosynthesis, increase the mineral accumulation, accelerate the growth, and obtain a significantly higher yield of Chinese kale.

RNA-Seq Analysis Demystify the Pathways of UV-A Supplementation in Different Photoperiods Integrated with Blue and Red Light on Morphology and Phytochemical Profile of Kale.

As an indispensable element in the morphology and phytochemical profile of plants, UV-A has proved to help promote the growth and quality of kale. In this study, UV-A supplementation in different photoperiods (light period supplemental UVA = LS, dark period supplemental UVA = DS, and light-dark period supplemental UVA = LDS) contributed to yielding greater biomass production (fresh weight, dry weight, and plant moisture content), thus improving morphology (plant height, stem diameter, etc.) and promoting higher phytochemicals content (flavonoids, vitamin c, etc.), especially glucosinolates. To fathom its mechanisms, this study, using RNA-seq, verified that UV-A supplementation treatments signally generated related DEGs of plant hormone signal pathway, circadian rhythm plant pathway, glucosinolate pathway, etc. Moreover, 2047 DEGs were obtained in WGCNA, illustrating the correlations between genes, treatments, and pathways. Additionally, DS remarkedly up-regulated related DEGs of the key pathways and ultimately contributed to promoting the stem diameter, plant height, etc., thus increasing the pigment, biomass, vitamin c, etc., enhancing the antioxidant capacity, and most importantly, boosting the accumulations of glucosinolates in kale. In short, this study displayed new insights into UV-A supplementation affected the pathways related to the morphology and phytochemical profile of kale in plant factories.

Effects of Pre-Harvest Supplemental UV-A Light on Growth and Quality of Chinese Kale.

The effects of supplemental UV-A (385 nm) period and UV-A intensity for 5 days before harvest (DBH) on growth, antioxidants, antioxidant capacity, and glucosinolates contents in Chinese kale (Brassica oleracea var. alboglabra Bailey) were studied in plant factory. In the experiment of the UV-A period, three treatments were designed with 10 W·m-2 UV-A supplement, T1(5 DBH), T2 (10 DBH), and no supplemental UV-A as control. In the experiment of UV-A intensity, four treatments were designed with 5 DBH, control (0 W·m-2), 5 w (5 W·m-2), 10 w (10 W·m-2), and 15 w (15 W·m-2). The growth light is as follows: 250 µmol·m-2·s-1; red light: white light = 2:3; photoperiod: 12/12. The growth and quality of Chinese kale were improved by supplemental UV-A LED. The plant height, stem diameter, and biomass of Chinese kale were the highest in the 5 W·m-2 treatment for 5 DBH. The contents of chlorophyll a, chlorophyll b, and total chlorophyll were only highly increased by 5 W·m-2 UV-A for 5 DBH, while there was no significant difference in the content of carotenoid among all treatments. The contents of soluble sugar and free amino acid were higher only under 10 DBH treatments than in control. The contents of total phenolic and total antioxidant capacity were the highest in 5 W·m-2 treatment for 5 DBH. There was a significant positive correlation between total phenolic content and DPPH and FRAP value. After 5 DBH treatments, the percentages and contents of total aliphatic glucosinolates, sinigrin (SIN), gluconapin (GNA), and glucobrassicanapin (GBN) were highly increased, while the percentages and contents of glucobrassicin (GBS), 4-methoxyglucobrassicin (4-MGBS), and Progoitrin (PRO) were significantly decreased, especially under 10 W·m-2 treatment. Our results show that UV-A LED supplements could improve the growth and quality of Chinese kale, and 5 W·m-2 UV-A LED with 5 DBH might be feasible for Chinese kale growth, and 10 W·m-2 UV-A LED with 5 DBH was better for aliphatic glucosinolates accumulation in Chinese kale.

Nitric Oxide Is Essential for Melatonin to Enhance Nitrate Tolerance of Cucumber Seedlings.

Melatonin (MT) and nitric oxide (NO) in plants can function cooperatively to alleviate salt stress, sodic alkaline stress and immune response, as well as adventitious root formation. The interaction of MT and NO on the nitrate stress tolerance of cucumber seedlings are not well understood. We investigated the effects of exogenous MT, NO donor (SNP) and NO scavenger (cPTIO) on the growth; photosynthesis; characteristics of root morphological; accumulation of mineral elements, endogenous NO, MT, IAA and ABA; and related genes expression in cucumber (Cucumis sativus L. "Jin You No. 1") seedlings grown under high nitrate condition (HN). The results showed that MT and NO independently alleviated the inhibition of growth and photosynthesis capacity of cucumber seedlings under nitrate stress. NO was required for MT to enhance the root activity, root length, lateral root number and the accumulation of calcium, magnesium and iron in the roots of cucumber seedlings grown under nitrate stress. Consistently, the expression of adventitious rootless 1 gene (CsARL1) was modulated. Furthermore, exogenous MT induced accumulation of endogenous MT, NO, indole-3-acetic acid (IAA) and abscisic acid (ABA), mainly within 24 h after treatment, in which MT and NO were further increased at 48 h and 96 h, IAA and ABA were further increased at 16 h in the presence of SNP. In contrast, the accumulation of endogenous IAA, MT and ABA slightly decreased within 24 h, NO significantly decreased at 192 h in the presence of cPTIO. Correspondingly, the expression levels of genes involved in nitrogen metabolism (CsNR1 and CsNR2), MT metabolism (CsT5H, CsSNAT2 and Cs2-ODD33), auxin carriers and response factors (CsAUX1, CsGH3.5, CsARF17), ABA synthesis and catabolism (CsNCED1, CsNCED3 and CsCYP707A1) were upregulated by MT, in which CsNR1, CsNR2, CsAUX1, CsNCED3 and CsT5H were further induced in the presence of SNP in roots of cucumber seedlings. These observations indicated that NO act as a crucial factor in MT, alleviating nitrate stress through regulating the mechanism of root growth in cucumber seedlings.

UVA-Radiation Exposure of Different Durations Promoted the Growth, Phytochemicals and Glucosinolate Biosynthesis of Chinese Kale.

Ultraviolet-A (UVA) (315-400 nm) is an essential environmental signal that regulates plant development and affects phytochemicals biosynthesis, including glucosinolate biosynthesis. The effects of different UVA (380 ± 10 nm, 40 µmol/m2/s) exposure durations, including 0 h/d (UV0), 6 h/d (UV6) and 12 h/d (UV12), on the growth and phytochemicals of Chinese kale (Brassica alboglabra) under white 250 µmol/m2/s LEDs were investigated. UVA exposure of different durations influenced the growth and phytochemicals biosynthesis of Chinese kale. Prolonging UVA irradiation throughout the growth cycle positively affected the growth and the development of Chinese kale, with evident increases in the dry weights of shoots and roots, plant height, stem diameter, specific leaf weight and flower budding rate. The application of UVA increased the soluble sugar content, whereas higher flavonoid content and antioxidant capacity (FRAP) and lower nitrate content were only observed in Chinese kale exposed to UV6 treatment. Besides, the qPCR assay showed that supplemental UVA-radiation exposure up-regulated the gene expressions of UVR8, transcription factors genes and genes related to the glucosinolate biosynthesis pathway, thereby promoting the accumulation of glucosinolates. Therefore, supplemental UVA-radiation exposure for 12 h/d was more conducive to plant growth, while supplemental UVA-radiation exposure for 6 h/d was better for phytochemical biosynthesis in Chinese kale in an artificial-light plant factory.

Effect of Supplemental UV-A Intensity on Growth and Quality of Kale under Red and Blue Light.

Different intensities of UV-A (6, 12, 18 µmol·m-2s-1) were applied in a plant factory to evaluate the combined influences of supplemental UV-A and red and blue light (Red:Blue = 1:1 at PPFD of 250 µmol·m-2 s-1) on the biomass, antioxidant activity and phytochemical accumulation of kale. Supplemental UV-A treatments (T1: 6 µmol·m-2 s-1, T2: 12 µmol·m-2 s-1 and T3: 18 µmol·m-2 s-1) resulted in higher moisture content, higher pigment content, and greater leaf area of kale while T2 reached its highest point. T2 treatment positively enhanced the antioxidant capacity, increased the contents of soluble protein, soluble sugar and reduced the nitrate content. T1 treatment markedly increased the content of aliphatic glucosinolate (GSL), whereas T2 treatment highly increased the contents of indolic GSL and total GSL. Genes related to GSL biosynthesis were down-regulated in CK and T3 treatments, while a majority of them were greatly up-regulated by T1 and T2. Hence, supplemental 12 µmol·m-2 s-1 UV-A might be a promising strategy to enhance the growth and quality of kale in a plant factory.

Supplemental Blue Light Frequencies Improve Ripening and Nutritional Qualities of Tomato Fruits.

Tomatoes (Solanum lycopersicum L. Micro-Tom) were grown in a plastic greenhouse. When plants anthesis, the 100 µmol m-2 s-1 blue light-emitting diode (LED) light (430 ± 10 nm) was supplemented from 6:00 to 18:00. There were 5 treatments, which contained different blue light frequencies with the same intensity: S6 (30 min blue light and 30 min pause), S8 (30 min blue light and 15 min pause), S10 (30 min blue and 8 min pause), S12 (continuous blue light for 12 h), and control (CK) (natural light, without any supplemental light). Agronomic traits and nutritional qualities of tomato fruits were measured at 30, 34, 38, 42, and 46 days after anthesis (DAA), respectively. Different frequencies of supplemental blue light could accelerate flowering of tomato plants and promote fruit ripening about 3-4 days early via promoting ethylene evolution of fruits, which significantly facilitated the processes of color change and maturity in tomato fruits. The contents of lycopene, total phenolic compounds, total flavonoids, vitamin C, and soluble sugar, as well as the overall antioxidant activity of tomato fruits were significantly enhanced by all the supplemental blue light treatments. In all, different frequencies of supplemental blue light prominently reinforced the antioxidant levels and nutritional qualities of tomato fruits, especially lycopene content, and S10 was more optimal for tomato fruits production in a plastic greenhouse.

Polysaccharide prediction in Ganoderma lucidum fruiting body by hyperspectral imaging.

Ganoderma lucidum is a traditional Chinese healthy food with many kinds of nutritious activities, and polysaccharide is one of its main active components. Ganoderma lucidum polysaccharide plays a vital role in improving human immunity and anti-oxidation. At present, the methods of detecting polysaccharide content of Ganoderma lucidum are destructive, and the steps are complicated and time-consuming. This study aims to explore the possibility of using hyperspectral imaging (HSI) to predict polysaccharide content in a nondestructive way during the growth of Ganoderma lucidum. The partial least square regression (PLSR) model shows good performance for Ganoderma lucidum ( R p 2  = 0.924, R P D p  = 3.622) with pretreatment method of Savitzky-Golay (SG) and standard normal variate (SNV), and feature selection method of successive projections algorithm (SPA). This study indicates that HSI can quickly and nondestructive detect the polysaccharide content of Ganoderma lucidum, provide guidance for the cultivation industry and improve the economic benefits of Ganoderma lucidum.

BcSOC1 Promotes Bolting and Stem Elongation in Flowering Chinese Cabbage.

Flowering Chinese cabbage is one of the most economically important stalk vegetables. However, the molecular mechanisms underlying bolting, which is directly related to stalk quality and yield, in this species remain unknown. Previously, we examined five key stem development stages in flowering Chinese cabbage. Here, we identified a gene, BcSOC1 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1), in flowering Chinese cabbage using transcriptome analysis, whose expression was positively correlated with bolting. Exogenous gibberellin (GA3) and low-temperature treatments significantly upregulated BcSOC1 and promoted early bolting and flowering. Additionally, BcSOC1 overexpression accelerated early flowering and stem elongation in both Arabidopsis and flowering Chinese cabbage, whereas its knockdown dramatically delayed bolting and flowering and inhibited stem elongation in the latter; the inhibition of stem elongation was more notable than delayed flowering. BcSOC1 overexpression also induced cell expansion by upregulating genes encoding cell wall structural proteins, such as BcEXPA11 (cell wall structural proteins and enzymes) and BcXTH3 (xyloglucan endotransglycosidase/hydrolase), upon exogenous GA3 and low-temperature treatments. Moreover, the length of pith cells was correlated with stem height, and BcSOC1 interacted with BcAGL6 (AGAMOUS-LIKE 6) and BcAGL24 (AGAMOUS-LIKE 24). Thus, BcSOC1 plays a vital role in bolting and stem elongation of flowering Chinese cabbage and may play a novel role in regulating stalk development, apart from the conserved function of Arabidopsis SOC1 in flowering alone.

Sexual Crossing, Chromosome-Level Genome Sequences, and Comparative Genomic Analyses for the Medicinal Mushroom Taiwanofungus Camphoratus (Syn. Antrodia Cinnamomea, Antrodia Camphorata).

Taiwanofungus camphoratus mushrooms are a complementary and alternative medicine for hangovers, cancer, hypertension, obesity, diabetes, and inflammation. Though Taiwanofungus camphoratus has attracted considerable biotechnological and pharmacological attention, neither classical genetic nor genomic approaches have been properly established for it. We isolated four sexually competent monokaryons from two T. camphoratus dikaryons used for the commercial cultivation of orange-red (HC1) and milky-white (SN1) mushrooms, respectively. We also sequenced, annotated, and comparatively analyzed high-quality and chromosome-level genome sequences of these four monokaryons. These genomic resources represent a valuable basis for understanding the biology, evolution, and secondary metabolite biosynthesis of this economically important mushrooms. We demonstrate that T. camphoratus has a tetrapolar mating system and that HC1 and SN1 represent two intraspecies isolates displaying karyotypic variation. Compared with several edible mushroom model organisms, T. camphoratus underwent a significant contraction in the gene family and individual gene numbers, most notably for plant, fungal, and bacterial cell-wall-degrading enzymes, explaining why T. camphoratus mushrooms are rare in natural environments, are difficult and time-consuming to artificially cultivate, and are susceptible to fungal and bacterial infections. Our results lay the foundation for an in-depth T. camphoratus study, including precise genetic manipulation, improvements to mushroom fruiting, and synthetic biology applications for producing natural medicinal products. IMPORTANCETaiwanofungus camphoratus (Tc) is a basidiomycete fungus that causes brown heart rot of the aromatic tree Cinnamomum kanehirae. The Tc fruiting bodies have been used to treat hangovers, abdominal pain, diarrhea, hypertension, and other diseases first by aboriginal Taiwanese and later by people in many countries. To establish classical genetic and genomic approaches for this economically important medicinal mushroom, we first isolated and characterized four sexually competent monokaryons from two dikaryons wildly used for commercial production of Tc mushrooms. We applied PacBio single molecule, real-time sequencing technology to determine the near-completed genome sequences of four monokaryons. These telomere-to-telomere and gapless haploid genome sequences reveal all genomic variants needed to be studied and discovered, including centromeres, telomeres, retrotransposons, mating type loci, biosynthetic, and metabolic gene clusters. Substantial interspecies diversities are also discovered between Tc and several other mushroom model organisms, including Agrocybe aegerita, Coprinopsis cinerea, and Schizophyllum commune, and Ganoderma lucidum.

Light Intensity and Photoperiod Affect Growth and Nutritional Quality of Brassica Microgreens.

We explored the effects of different light intensities and photoperiods on the growth, nutritional quality and antioxidant properties of two Brassicaceae microgreens (cabbage Brassica oleracea L. and Chinese kale Brassica alboglabra Bailey). There were two experiments: (1) four photosynthetic photon flux densities (PPFD) of 30, 50, 70 or 90 µmoL·m-2·s-1 with red:blue:green = 1:1:1 light-emitting diodes (LEDs); (2) five photoperiods of 12, 14, 16, 18 or 20 h·d-1. With the increase of light intensity, the hypocotyl length of cabbage and Chinese kale microgreens shortened. PPFD of 90 µmol·m-2·s-1 was beneficial to improve the nutritional quality of cabbage microgreens, which had higher contents of chlorophyll, carotenoids, soluble sugar, soluble protein and vitamin C, as well as increased antioxidant capacity. The optimal PPFD for Chinese kale microgreens was 70 µmol·m-2·s-1. Increasing light intensity could increase the antioxidant capacity of cabbage and Chinese kale microgreens, while not significantly affecting glucosinolate (GS) content. The dry and fresh weight of cabbage and Chinese kale microgreens were maximized with a 14-h·d-1 photoperiod. The chlorophyll, carotenoid and soluble protein content in cabbage and Chinese kale microgreens were highest for a 16-h·d-1 photoperiod. The lowest total GS content was found in cabbage microgreens under a 12-h·d-1 photoperiod and in Chinese kale microgreens under 16-h·d-1 photoperiod. In conclusion, the photoperiod of 14~16 h·d-1, and 90 µmol·m-2·s-1 and 70 µmol·m-2·s-1 PPFD for cabbage and Chinese kale microgreens, respectively, were optimal for cultivation.

Complete Genome Sequences and Genome-Wide Characterization of Trichoderma Biocontrol Agents Provide New Insights into their Evolution and Variation in Genome Organization, Sexual Development, and Fungal-Plant Interactions.

Trichoderma spp. represent one of the most important fungal genera to mankind and in natural environments. The genus harbors prolific producers of wood-decaying enzymes, biocontrol agents against plant pathogens, plant-growth-promoting biofertilizers, as well as model organisms for studying fungal-plant-plant pathogen interactions. Pursuing highly accurate, contiguous, and chromosome-level reference genomes has become a primary goal of fungal research communities. Here, we report the chromosome-level genomic sequences and whole-genome annotation data sets of four strains used as biocontrol agents or biofertilizers (Trichoderma virens Gv29-8, Trichoderma virens FT-333, Trichoderma asperellum FT-101, and Trichoderma atroviride P1). Our results provide comprehensive categorization, correct positioning, and evolutionary detail of both nuclear and mitochondrial genomes, including telomeres, AT-rich blocks, centromeres, transposons, mating-type loci, nuclear-encoded mitochondrial sequences, as well as many new secondary metabolic and carbohydrate-active enzyme gene clusters. We have also identified evolutionarily conserved core genes contributing to plant-fungal interactions, as well as variations potentially linked to key behavioral traits such as sex, genome defense, secondary metabolism, and mycoparasitism. The genomic resources we provide herein significantly extend our knowledge not only of this economically important fungal genus, but also fungal evolution and basic biology in general. IMPORTANCE Telomere-to-telomere and gapless reference genome assemblies are necessary to ensure that all genomic variants are studied and discovered, including centromeres, telomeres, AT-rich blocks, mating type loci, biosynthetic, and metabolic gene clusters. Here, we applied long-range sequencing technologies to determine the near-completed genome sequences of four widely used biocontrol agents or biofertilizers: Trichoderma virens Gv29-8 and FT-333, Trichoderma asperellum FT-101, and Trichoderma atroviride P1. Like those of three Trichoderma reesei wild isolates [QM6a, CBS999.97(MAT1-1) and CBS999.97(MAT1-2)] we reported previously, these four biocontrol agent genomes each contain seven nuclear chromosomes and a circular mitochondrial genome. Substantial intraspecies and intragenus diversities are also discovered, including single nucleotide polymorphisms, chromosome shuffling, as well as genomic relics derived from historical transposition events and repeat-induced point (RIP) mutations.

Supplementary Far-Red and Blue Lights Influence the Biomass and Phytochemical Profiles of Two Lettuce Cultivars in Plant Factory.

Three different LED spectra (W: White light; WFR: W + far-red light; WB: W + blue light) with similar photosynthetic photon flux density (PPFD) were designed to explore the effects of supplementary far-red and blue lights on leaf color, biomass and phytochemicals of two cultivars of red-leaf lettuce ("Yanzhi" and "Red Butter") in an artificial lighting plant factory. Lettuce plants under WB had redder leaf color and significantly higher contents of pigments, such as chlorophyll a, chlorophyll b, chlorophyll (a + b) and anthocyanins. The accumulation of health-promoting compounds, such as vitamin C, vitamin A, total phenolic compounds, total flavonoids and anthocyanins in the two lettuce cultivars were obviously enhanced by WB. Lettuce under WFR showed remarkable increase in fresh weight and dry weight; meanwhile, significant decreases of pigments, total phenolic compounds, total flavonoids and vitamin C were found. Thus, in the plant factory system, the application of WB can improve the coloration and quality of red leaf lettuce while WFR was encouraged for the purpose of elevating the yield of lettuce.

Identification of DELLA Genes and Key Stage for GA Sensitivity in Bolting and Flowering of Flowering Chinese Cabbage.

Flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) is an important and extensively cultivated vegetable in south China, and its stalk development is mainly regulated by gibberellin (GA). DELLA proteins negatively regulate GA signal transduction and may play an important role in determining bolting and flowering. Nevertheless, no systematic study of the DELLA gene family has been undertaken in flowering Chinese cabbage. In the present study, we found that the two-true-leaf spraying of gibberellin A3 (GA3) did not promote bolting but did promote flowering, whereas the three-true-leaf spraying of GA3 promoted both bolting and flowering. In addition, we identified five DELLA genes in flowering Chinese cabbage. All five proteins contained DELLA, VHYNP, VHIID, and SAW conserved domains. Protein-protein interaction results showed that in the presence of GA3, all five DELLA proteins interacted with BcGID1b (GA-INSENSITIVE DWARF 1b) but not with BcGID1a (GA-INSENSITIVE DWARF 1a) or BcGID1c (GA-INSENSITIVE DWARF 1c). Their expression analysis showed that the DELLA genes exhibited tissue-specific expression, and their reversible expression profiles responded to exogenous GA3 depending on the treatment stage. We also found that the DELLA genes showed distinct expression patterns in the two varieties of flowering Chinese cabbage. BcRGL1 may play a major role in the early bud differentiation process of different varieties, affecting bolting and flowering. Taken together, these results provide a theoretical basis for further dissecting the DELLA regulatory mechanism in the bolting and flowering of flowering Chinese cabbage.