Search Results (17)

Lotus (Nelumbo nucifera Gaertn.) is a quintessential medicinal and edible plant, exhibiting marked differences in therapeutic effects among its various parts. The lotus seed constitutes a key component of this plant. Notably, the entire seed and the plumule display distinct medicinal properties. To investigate the “homologous plants with different effects” phenomenon in traditional Chinese medicine, this study established a Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging (MALDI-MSI) method. This study employed immature lotus seeds as the experimental material, diverging from the mature seeds conventionally used. Conductive double-sided tape was employed for sample preparation, and complete longitudinal sections of the seeds were obtained, followed by MALDI-MSI analysis to identify and visualize the spatial distribution of characteristic secondary metabolites within the entire seeds. The results unveiled the diversity of metabolites in lotus seeds and their differential distribution across tissues, with pronounced distinctions in the plumule. A total of 152 metabolites spanning 13 categories were identified in lotus seeds, with 134, 89, 51, and 98 metabolites discerned in the pericarp, seed coat, cotyledon, and plumule, respectively. Strikingly, young lotus seeds were devoid of liensinine/isoliensinine and neferine, the dominant alkaloids of mature lotus seed plumule, revealing an early-stage alkaloid profile that sharply contrasts with the well-documented abundance found in mature seeds and has rarely been reported. We further propose a biosynthetic pathway to explain the presence of the detected benzylisoquinoline and the absence of the undetected bisbenzylisoquinoline alkaloids in this study. These findings present the first comprehensive metabolic atlas of immature lotus seeds, systematically exposing the pronounced chemical divergence from their mature counterparts, and thus lays a metabolomic foundation for dissecting the spatiotemporal mechanisms underlying the nutritional and medicinal value of lotus seeds. Full article

Corn cockle (Agrostemma githago L. (Lychnis githago (L.) Scop.)) is the main ingredient in some plant preparations for biostimulation in agriculture, and it elicits many positive responses. In our study, we attempted to determine if the fresh and dry plant material of A. githago contained auxin-like and cytokinin-like growth regulators (PGRs). Cucumis and mung bean bioassays were used to determine the presence of auxin-like PGRs and Cucumis and Triticum bioassays were used to determine the presence of cytokinin-like PGRs. A water solution derived from the crushed, homogenized and extracted seeds, fresh and dry seedlings, and fresh and dry young plants showed auxin-like activity in both bioassays. The activity in the Cucumis bioassay corresponded to 0.5 to 2 mg L⁻¹ of Indole-3-butyric acid (IBA), and in the mung bean bioassay, the activity corresponded to 0.5 to 4 mg L⁻¹ of IBA. While the same water solutions showed weak or no cytokinin-like activity in the Cucumis cotyledon expansion bioassay, and they showed an activity of approximately 0.5 to 1 mg L⁻¹ of 6-Benzylaminopurine (BAP) in the Triticum bioassay. An LC-MS analysis confirmed the presence of free auxins, low levels of or no auxin analogues, a small amount of free cytokinins and a higher level of their cytokinin analogues in the samples, seeds, dry seedlings and young plants of A. githago, which was likely related to the fine-tuning between the free and analogue forms of the PGRs in the water solutions used in the experiments. Full article

Caragana intermedia is a perennial shrub species in the genus Caragana (Fabaceae), demonstrating remarkable stress resistance and adaptability. However, research on its somatic embryogenesis (SE) and genetic transformation techniques remains limited. In this study, we established an SE system by utilizing immature cotyledons isolated from young C. intermedia seeds. Our findings demonstrated that the immature cotyledons at 6–7 weeks after flowering (WAF) were the best explants for SE. The optimal embryo induction medium consisted of an MS basal medium supplemented with 5 mg/L α-naphthaleneacetic acid (NAA), 3 mg/L 6-benzylaminopurine (6-BA), 30 g/L sucrose, 7 g/L agar, and 500 mg/L hydrolyzed casein. Cotyledon-stage embryos germinated on a half-strength MS medium, exhibiting a 34.36% germination rate. Based on the SE system, we developed a preliminary genetic transformation system using the RUBY reporter gene, which successfully generated transgenic calli and cotyledon-stage embryos. The establishment of the SE system is expected to shorten breeding cycles, facilitate propagation of superior cultivars, and support large-scale industrial applications in C. intermedia. Furthermore, the stable transformation system provides a platform for molecular breeding and gene function verification. Full article

Highly differentiated tissues and organs play essential biological functions in multicellular organisms. Coordination of organ developmental process with tissue differentiation is necessary to achieve proper development of mature organs, but mechanisms for such coordination are not well understood. We used cotyledon margin cells from Arabidopsis plant as a new model system to investigate cell elongation and cell division during organ growth and found that margin cells endured a developmental phase transition from the “elongation” phase to the “elongation and division” phase at the early stage in germinating seedlings. We also discovered that the stem cell factors BARELY ANY MERISTEM 1 (BAM1) and WUSCHEL-related homeobox1 (WOX1) are involved in the regulation of margin cell developmental phase transition. Furthermore, exogenous auxin treatment (1 nanomolar,nM) promotes cell division, especially longitudinal cell division. This promotion of cell division did not occur in bam1 and wox1 mutants. Based on these findings, we hypothesized a new “moderate auxin concentration” model which emphasizes that a moderate auxin concentration is the key to triggering the developmental transition of meristematic cells. Full article

Adenocaulon himalaicum is widely distributed across Asia. In its early growth stages, A. himalaicum is traditionally consumed as a food source in Korea. Although previous research has identified the presence of bioactive compounds in A. himalaicum extract, suggesting its potential as a medicinal resource, the phytochemical profile of A. himalaicum extract has not been extensively determined. This investigation aimed to identify the phytochemicals present in the true leaf and cotyledon of A. himalaicum (TLA and CLA, respectively) and evaluate their radical-scavenging activity. By performing LC-MS/MS and HPLC, varying amounts of isochlorogenic acid A, cryptochlorogenic acid, isochlorogenic acid B, rutin, chlorogenic acid, hyperin, and neochlorogenic acid were detected in the TLA and CLA extracts. Chlorogenic acid (9.002 mg/g DW), isochlorogenic acid A (28.512 mg/g DW), and isochlorogenic acid B (12.223 mg/g DW) were the most abundant in TLA. TLA exhibited higher phytochemical content (49.737 mg/g DW), total phenolic content (45.51 mg tannic acid equivalent/g extract), and total flavonoid content (16.24 mg quercetin equivalent/g extract) than CLA. Moreover, the radical-scavenging activity of TLA was two times higher than that of CLA. The young leaf of A. himalaicum has a rich phytochemical profile and robust antioxidant activity; hence, it has potential as natural antioxidant sources for human health and valuable pharmacognosy raw materials for pharmaceutical and functional food applications. Full article

Microplants are vegetables, grains and aromatic herbs that are consumed in the stage of young plants, without roots, developed after the germination stage, in the stage of cotyledons and which have a high content of nutrients (antioxidants, vitamins, minerals, fatty acids, lutein, β-carotene, proteins and fibers, etc.), which makes them functional, concentrated foods capable of feeding the world’s ever-growing population. The significant amounts of antioxidants in microgreens have the role of neutralizing free radicals and reducing their harmful impact on human health. The microgreens studied were spinach (Spinacia oleracea) cultivar ‘Lorelay’, mustard (Sinapis alba) cultivar ‘White’ and radish (Raphanus sativus) cultivar ‘Red Rambo’, tested on hemp and coconut substrates and under the influence of the organic biostimulator Biohumussol, based on humic acids. The antioxidant content of the plants was determined by analyzing total carotenoids, lycopene, chlorophyll, β-carotene, polyphenols and flavonoids, as well as the antioxidant activity by ABTS and DPPH methods. The obtained results indicated that the reaction of the plant material depends on the composition of the substrate and the presence of the applied biostimulator. The highest contents of substances with an antioxidant role were obtained from the microgreens on the hemp substrate, especially mustard and radishes, and the biostimulator proved to be compatible with the spinach microgreens. Full article

Mango (Mangifera indica L.) is one of the most significant tropical and subtropical fruit species, with high ecological and economic value. However, research on the in vitro culture of mangoes is relatively weak, so establishing an efficient and stable mango plant regeneration system is of great significance. In this study, a preliminary mango regeneration system was established with Mangifera indica L. cv. Keitt from young branches as the starting explants. The results showed that the optimal plant growth regulator (PGR) formula for direct adventitious shoot induction on the branches was 1 mg/L 6-benzylaminopurine (6-BA) + 0.1 mg/L a-naphthaleneacetic acid (NAA), with an adventitious shoot induction rate of 73.63% and an average of 6.76 adventitious shoots. The optimal basal medium for adventitious shoot induction was wood plant medium (WPM), with an adventitious shoot induction rate of 63.87% and an average of 5.21 adventitious shoots. The optimal culture medium for adventitious shoot elongation was WPM + 1 mg/L 6-BA + 0.5 mg/L NAA, with an adventitious shoot elongation rate of 89.33% and an average length of 5.17 cm. The optimal formula for the induction of mango rooting was Douglas fir cotyledon revised medium (DCR) + 3 mg/L indole-3-butyric acid (IBA), with a maximum rooting rate of 66.13% and an average rooting quantity of 6.43. The genetic fidelity of the in vitro-regenerated plants was evaluated using inter-simple sequence repeat (ISSR) molecular markers. There was no difference between the in vitro-regenerated plants and the parent plant. This study provides an efficient and stable propagation system for Mangifera indica L., laying the foundation for its rapid propagation and genetic improvement. Full article

The successful establishment of seedlings is very important for plant regeneration, but it is vulnerable to many factors at this stage. Cotyledon damage will directly affect the health of seedlings, thus affecting the regeneration of the plant population. However, little is known about the effects of different cotyledon loss degrees of large and small seeds on seedling growth. We investigated the effects of 1/4 (light excision), 1/2 (moderate excision), and complete excision of cotyledons (heavy excision) on the growth characteristics of seedlings germinating from different sizes of seeds. The results showed that (1) shoot height, basal stem diameter, number of leaves, leaf area per plant, specific leaf area, and biomass were significantly higher in large-seeded seedlings than in small-seeded seedlings; (2) slight cotyledon excision had no effect on the biomass of large-seeded seedlings but significantly reduced the biomass of small-seeded seedlings. Our study highlights that large-seeded seedlings are more tolerant than small-seeded seedlings in the early seedling recruitment, suggesting that large-seeded seedlings have a strong fitness for recruitment in young populations of Q. wutaishanica. Full article

Polyploidy was induced in Melia volkensii (Mukau), a valuable native tree from the semi-arid regions of East Africa. Cotyledons of diploid M. volkensii (2n = 2x = 28) were treated with oryzalin for 0 (control), 1, 2, or 3 h with or without pretreatment with 1.1 µM thidiazuron. Cotyledons treated with 10 mg·L⁻¹ oryzalin for three hours yielded 40% tetraploids. Pretreatment of cotyledons with thidiazuron for 18 days followed by treatment with oryzalin increased tetraploid plant production to 52.5%, but this also yielded more mixoploids. Compared to diploid M. volkensii, the tetraploid in vitro and young potted plants were compacter, with thicker stems, wider leaves, and a low density of longer and wider stomata. In the coming years, tetraploid M. volkensii plants will be observed in field trials and serve as a basis for further breeding efforts. Full article

Leaf margin serration is a morphological characteristic in plants. The CUC2 (CUP-SHAPED COTYLEDON 2) gene plays an important role in the outgrowth of leaf teeth and enhances leaf serration via suppression of growth in the sinus. In this study, we isolated the BcCUC2 gene from Pak-choi (Brassica rapa ssp. chinensis), which contains a 1104 bp coding sequence, encoding 367 amino acid residues. Multiple sequence alignment exhibited that the BcCUC2 gene has a typical conserved NAC domain, and phylogenetic relationship analysis showed that the BcCUC2 protein has high identity with Cruciferae plants (Brassica oleracea, Arabidopsis thaliana, and Cardamine hirsuta). The tissue-specific expression analysis displayed that the BcCUC2 gene has relatively high transcript abundance in floral organs. Meanwhile, the expression profile of BcCUC2 was relatively higher in the ‘082’ lines with serrate leaf margins than the ‘001’ lines with smooth leaf margins in young leaves, roots, and hypocotyls. In addition, the transcript level of BcCUC2 was up-regulated by IAA and GA3 treatment, especially at 1–3 h. The subcellular localization assay demonstrated that BcCUC2 was a nuclear-target protein. Furthermore, leaf serration occurred, and the number of the inflorescence stem was increased in the transgenic Arabidopsis thaliana plants’ overexpressed BcCUC2 gene. These data illustrated that BcCUC2 is involved in the development of leaf margin serration, lateral branches, and floral organs, contributing to further uncovering and perfecting the regulation mechanism of leaf serration in Pak-choi. Full article

ODAP (N-oxalyl-L-2,3-diaminopropionic acid) is present in the seeds of grass pea. In this study, variation of total ODAP accumulation in leaves throughout the crop growth starting from 40 days after sowing to maturity, and the distribution pattern of ODAP in different plant parts including the seeds at the mature stage was analyzed. Five grass pea accessions were evaluated for two subsequent growing seasons in one location of ICARDA, Aleppo (Syria). The results found that the rate of accumulation of total ODAP varied during plant development. Increased rates of synthesis were noticed in young leaves of grass pea. The highest total ODAP content in leaves was noted in the early growth stage (40–50 days after sowing). Mean total ODAP content in leaves ranged from 0.17 to 0.96 percent during 2010–2011 and from 0.19 to 1.28 percent during 2011–2012. During maturity, the total ODAP content was lowest in the seeds than in leaves, stems, pod cover, seed coat, and cotyledons. The ranges of total ODAP content were 0.13 (seed)–0.34 (stem), 0.20 (seed)–1.01 (leaf), 0.22 (seed)–0.62 (leaf), 0.21 (seed)–0.66 (leaf), and 0.21 (seed)–0.78 (leaf) percent in B387, B222, B390, Bio-520, and B587 accessions, respectively, during maturity. The results indicated that the rate of accumulation and synthesis of total ODAP varied during the plant lifespan. The lowest total ODAP content of leaves was observed after 130 days of sowing. The lower total ODAP content after the early vegetative stage of grass pea plants makes them suitable as a feed. Full article

Cotton (Gossypium hirsutum) is the largest fibre crop globally and an important oilseed crop. Rising temperatures and declining water supplies, which are also impacting soil salinity, threaten cotton plant productivity. Germination, emergence and young seedling stages in cotton are highly sensitive to salinity and heat stresses. Brassinosteroids (BRs) are plant steroid hormones that are essential for proper plant growth and development and also promote tolerance to a range of environmental stresses. Cotton seeds were primed with BR (24-epibrassinolide) alone or in combination with other hormones (abscisic acid, auxin and gibberellic acid) and tested for germination and early seedling growth. BR promoted germination under no stress as well as under salinity and heat stress conditions, while other hormones were ineffective under stress conditions. BR also promoted cotyledon opening and the development of lateral roots in germinated seedlings. The ability of BR to positively impact seedling growth across different stress conditions suggests that priming cotton seeds with BR may help in early and successful establishment of seedlings, which may benefit the plant through its lifecycle. Full article

The present study aimed to investigate the enzymatic potential of Silybum marianum leaves to bioconvert phenolic acids produced in S. marianum callus into silymarin derivatives as chemopreventive agent. Here we demonstrate that despite the fact that leaves of S. marianum did not accumulate silymarin themselves, expanding leaves had the full capacity to convert di-caffeoylquinic acid to silymarin complex. This was proven by HPLC separations coupled with electrospray ionization mass spectrometry (ESI-MS) analysis. Soaking the leaf discs with S. marianum callus extract for different times revealed that silymarin derivatives had been formed at high yield after 16 h. Bioconverted products displayed the same retention time and the same mass spectra (MS or MS/MS) as standard silymarin. Bioconversion was achieved only when using leaves of a specific age, as both very young and old leaves failed to produce silymarin from callus extract. Only medium leaves had the metabolic capacity to convert callus components into silymarin. The results revealed higher activities of enzymes of the phenylpropanoid pathway in medium leaves than in young and old leaves. It is concluded that cotyledon-derived callus efficiently produces compounds that can be bio-converted to flavonolignans in leaves tissue of S. marianum. Full article

Spring frost poses a challenge for all major crops and, in the case of Lupinus mutabilis (Andean lupin) can cause severe damage or even total loss of the crop. Within the LIBBIO project consortium, we conducted a series of experiments in order to develop a suitable protocol for screening lupin germplasm under frost-simulation conditions. Four lupin accessions, one Lupinus albus and three Andean lupins were used in the experiments (L. albus Mihai, L. mutabilis LIB 220, LIB 221, LIB 222). Seedlings at four developmental stages were challenged with five different levels of ‘frost’ stress from low (−2 °C) to high (−10 °C). Notably, young seedling (cotyledons just breaking through the soil surface) showed little evidence of frost damage for temperatures down to −6 °C. At −8 °C, however, damage was evident, suggesting a cold tolerance threshold occurs at this temperature. Interestingly, for later developmental stages, when the first and second leaves were visible, notable differences were observed starting at −6 °C. The results indicate that the plant growth stage is an important parameter when screening for frost tolerance in germplasm. Overall, by identifying Andean lupin genotypes adapted to high abiotic stress factors, farmers will be able to use it as a reference crop with potentially a commercial interest from the food sector, or cosmetics, and biofuel industries. Full article

CBL-interacting protein kinase (CIPK) family is a unique group of serine/threonine protein kinase family identified in plants. Among this family, AtCIPK23 and its homologs in some plants are taken as a notable group for their importance in ions transport and stress responses. However, there are limited reports on their roles in seedling growth and development, especially in Solanaceae plants. In this study, NtCIPK23, a homolog of AtCIPK23 was cloned from Nicotiana tabacum. Expression analysis showed that NtCIPK23 is mainly expressed in the radicle, hypocotyl, and cotyledons of young tobacco seedlings. The transcriptional level of NtCIPK23 changes rapidly and spatiotemporally during seed germination and early seedling growth. To study the biological function of NtCIPK23 at these stages, the overexpressing and CRISPR/Cas9-mediated knock-out (ntcipk23) tobacco lines were generated. Phenotype analysis indicated that knock-out of NtCIPK23 significantly delays seed germination and the appearance of green cotyledon of young tobacco seedling. Overexpression of NtCIPK23 promotes cotyledon expansion and hypocotyl elongation of young tobacco seedlings. The expression of NtCIPK23 in hypocotyl is strongly upregulated by darkness and inhibited under light, suggesting that a regulatory mechanism of light might underlie. Consistently, a more obvious difference in hypocotyl length among different tobacco materials was observed in the dark, compared to that under the light, indicating that the upregulation of NtCIPK23 contributes greatly to the hypocotyl elongation. Taken together, NtCIPK23 not only enhances tobacco seed germination, but also accelerate early seedling growth by promoting cotyledon greening rate, cotyledon expansion and hypocotyl elongation of young tobacco seedlings. Full article