Botanical Studies最新文献

Tecoma stans is a widely distributed tall ornamental shrub in the plains of Indian subcontinent and is considered an invasive species across Argentina, Australia, South Africa, Pacific Islands and tropical regions of Asia. Besides having an ornamental significance, T. stans has been extensively investigated for its pharmaceutical applications as a source of bioactive compounds. In addition, the shrub is cultivated commercially as a potted flowering plant. We believe that T. stans, being a hardy, invasive and aggressively growing species, holds a considerable potential and a promising solution for re-greening waste and degraded lands outside its invasive range, due to its wider adaptability and drought tolerant characteristics. The shrub is an excellent source of pollen and nectar, that attracts diverse insect-pollinators and several species of birds. The prudent plantation of this shrub has the potential to restore the ecology of barren landscapes, that can change its perspective of 'being invasive' to 'being ecologically healthy' across the tropical, semi-arid and subtropical regions worldwide. This paper reviews the current updates on ecology, life cycle including morphology, plant growth characteristics, flowering phenology, reproductive biology, breeding system and fruiting of T. stans. In addition, details on insect-pollinator diversity and natural regeneration potential have also been discussed, besides highlighting its therapeutic and landscape use.

Pollen germination is a crucial process in the life cycle of flowering plants, signifying the transition of quiescent pollen grains into active growth. This study delves into the dynamic changes within organelles and the pivotal role of autophagy during lily pollen germination. Initially, mature pollen grains harbor undifferentiated organelles, including amyloplasts, mitochondria, and the Golgi apparatus. However, germination unveils remarkable transformations, such as the redifferentiation of amyloplasts accompanied by starch granule accumulation. We investigate the self-sustained nature of amylogenesis during germination, shedding light on its association with osmotic pressure. Employing BODIPY 493/503 staining, we tracked lipid body distribution throughout pollen germination, both with or without autophagy inhibitors (3-MA, NEM). Typically, lipid bodies undergo polarized movement from pollen grains into elongating pollen tubes, a process crucial for directional growth. Inhibiting autophagy disrupted this essential lipid body redistribution, underscoring the interaction between autophagy and lipid body dynamics. Notably, the presence of tubular endoplasmic reticulum (ER)-like structures associated with developing amyloplasts and lipid bodies implies their participation in autophagy. Starch granules, lipid bodies, and membrane remnants observed within vacuoles further reinforce the involvement of autophagic processes. Among the autophagy inhibitors, particularly BFA, significantly impede germination and growth, thereby affecting Golgi morphology. Immunogold labeling substantiates the pivotal role of the ER in forming autophagosome-like compartments and protein localization. Our proposed speculative model of pollen germination encompasses proplastid differentiation and autophagosome formation. This study advances our understanding of organelle dynamics and autophagy during pollen germination, providing valuable insights into the realm of plant reproductive physiology.

Background: Recently, researchers are focusing on creating new tools to combat the antibiotic resistant bacteria and malignancy issues, which pose significant threats to humanity. Biosynthesized silver nanoparticles (AgNPs) are thought to be a potential solution to these issues. The biosynthesis method, known for its environmentally friendly and cost-effective characteristics, can produce small-sized AgNPs with antimicrobial and anticancer properties. In this study, AgNPs were bio-fabricated from the distilled water and methanolic extracts of Viburnum grandiflorum leaves. Physio-chemical characterization of the bio-fabricated AgNPs was conducted using UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray, and X-ray diffraction analysis.

Results: AgNPs produced from the methanol extract were smaller in size (12.28 nm) compared to those from the aqueous extract (17.77 nm). The bioengineered AgNPs exhibited a circular shape with a crystalline nature. These biosynthesized AgNPs demonstrated excellent bactericidal activity against both gram-negative (Pseudomonas aeruginosa) and gram-positive (Staphylococcus aureus) bacteria. Highest antibacterial activity was observed with the methanol extract against P. aeruginosa (14.66 ± 0.74 mm). AgNPs from the methanol extract also displayed the highest antioxidant activity, with an IC₅₀ value of 188.00 ± 2.67 μg/mL against 2,2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, AgNPs exhibited notable cytotoxic activity against Rhabdomyosarcoma cell line (RD cell) of human muscle cancer cell. The IC₅₀ values calculated from the MTT assay were 26.28 ± 1.58 and 21.49 ± 1.44 μg/mL for AgNPs synthesized from aqueous and methanol extracts, respectively.

Conclusion: The methanol extract of V. grandiflorum leaves demonstrates significant potential for synthesizing AgNPs with effective antibacterial, antioxidant, and anticancer actions, making them applicable in various biomedical applications.

Background: Angelica L. sensu lato is a taxonomically complex genus, and many studies have utilized morphological and molecular features to resolve its classification issues. In Taiwan, there are six taxa within Angelica, and their taxonomic treatments have been a subject of controversy. In this study, we conducted a comprehensive analysis incorporating morphological and molecular (cpDNA and nrDNA) characteristics to revise the taxonomic treatments of Angelica in Taiwan.

Results: As a result of our research, we have revised the classification between A. dahurica var. formosana and A. pubescens and merged two varieties of A. morrisonicola into a single taxon. A new taxon, A. aliensis, has been identified and found to share a close relationship with A. tarokoensis. Based on the morphological and molecular characteristics data, it has been determined that the former three taxa should be grouped into the Eurasian Angelica clade, while the remaining four taxa should belong to the littoral Angelica clade. Furthermore, Angelica species in Taiwan distributed at higher altitudes displayed higher genetic diversity, implying that the central mountain range of Taiwan serves as a significant reservoir of plant biodiversity. Genetic drift, such as bottlenecks, has been identified as a potential factor leading to the fixation or reduction of genetic diversity of populations in most Angelica species. We provide key to taxa, synopsis, phenology, and distribution for each taxon of Taiwan.

Conclusions: Our comprehensive analysis of morphological and molecular features has shed light on the taxonomic complexities within Angelica in Taiwan, resolving taxonomic issues and providing valuable insights into the phylogenetic relationships of Angelica in Taiwan.

Background: The bimolecular fluorescence complementation (BiFC) assay is commonly used for investigating protein-protein interactions. While several BiFC detection systems have been developed, there is a limited amount of research focused on using laser scanning confocal microscope (LSCM) techniques to observe protoplasts. Protoplasts are more susceptible to damage and instability compared to their original cell state due to the preparation treatments they undergo, which makes it challenging for researchers to manipulate them during observation under LSCMs. Therefore, it is crucial to utilize microscope techniques properly and efficiently in BiFC assays.

Results: When the target fluorescence is weak, the autofluorescence of chloroplast particles in protoplasts can interfere with the detection of BiFC signals localized in the nuclear region. Spectrum analysis revealed that chloroplast autofluorescence can be excited by lasers of various types, with the highest fluorescence signal observed at around 660 nm. Furthermore, our investigation into the impact of different pipette tips on the integrity of protoplast samples indicated that the utilization of cut tips with larger openings can mitigate cell breakage. We presented a workflow of LSCM techniques for investigating protoplast BiFC and discussed the microscopic manipulation involved in sample preparation and image capturing.

Conclusion: When the BiFC signals are weak, they may be affected by chloroplast autofluorescence. However, when used properly, the autofluorescence of chloroplasts can serve as an excellent internal marker for effectively distinguishing other signals. In combination with other findings, this study can provide valuable reference for researchers conducting BiFC assays and related studies.

Background: Traditional breeding methods have long been employed worldwide for the evaluation and development of pepper cultivars. However, these methods necessitate multiple generations of screening, line development, evaluation, recognition, and crossing to obtain highly homozygous lines. In contrast, in vitro anther-derived microspore culture represents a rapid method to generate homozygous lines within a single generation. In the present study, we have optimized a protocol for microspore embryogenesis from anther cultures of pepper hybrids Orobelle and Bomby.

Results: We achieved early and successful embryo formation from both genotypes by subjecting the buds to a cold pretreatment at 4 °C for 4 days. Our optimized culture medium, comprised of MS medium supplemented with 4 mg/L NAA, 1 mg/L BAP, 0.25% activated charcoal, 2.6 g/L gelrite, 30 g/L sucrose, and 15 mg/L silver nitrate, exhibited the highest efficiency in embryo formation (1.85% and 1.46%) for Orobelle and Bomby, respectively. Furthermore, successful plant regeneration from the anther derived microspore embryos was accomplished using half-strength MS medium fortified with 2% sucrose and 0.1 mg/L 6-benzylaminopurine (BA), solidified with 2.6 g/L gelrite. The ploidy status of the microspore-derived plantlets was analyzed using flow cytometry technique. Notably, the haploid plants exhibited distinct characteristics such as reduced plant height, leaf length, leaf width, and shorter internode length when compared to their diploid counterparts derived from seeds.

Conclusion: Our findings highlight the potential of anther culture and microspore embryogenesis as an advanced method for accelerating pepper breeding programs, enabling the rapid production of superior homozygous lines.

Background: Endophytic fungi have proven to be a rich source of novel natural products with a wide-array of biological activities and higher levels of structural diversity.

Results: Chemical investigation on the liquid- and solid-state fermented products of Chaetomium globosum Km1226 isolated from the littoral medicinal herb Atriplex maximowicziana Makino resulted in the isolation of compounds 1-14. Their structures were determined by spectroscopic analysis as three previously undescribed C₁₃-polyketides, namely aureonitol C (1), mollipilins G (2), and H (3), along with eleven known compounds 4-14. Among these, mollipilin A (5) exhibited significant nitric oxide production inhibitory activity in LPS-induced BV-2 microglial cells with an IC₅₀ value of 0.7 ± 0.1 µM, and chaetoglobosin D (10) displayed potent anti-angiogenesis property in human endothelial progenitor cells (EPCs) with an IC₅₀ value of 0.8 ± 0.3 µM.

Conclusions: Three previously unreported compounds 1-3 were isolated and identified. Mollipilin A (5) and chaetoglobosin D (10) could possibly be developed as anti-inflammatory and anti-angiogenic lead drugs, respectively.

Background: Leaf morphology and epidermal characters are important for phylogenetic and taxonomic studies of many plants, but there is currently insufficient data to use them to help distinguish species of Gagea, which is a taxonomically difficult genus mainly due to polyploidy and hybridization. Therefore, leaf morphology and epidermal characters of Gagea were studied to assess the characters that can be used to elucidate the taxonomy and systematics of 14 species of Gagea collected in Xinjiang, China. Using light microscopy (LM), six qualitative and three quantitative leaf epidermal anatomical characters were examined for both the adaxial and abaxial surfaces. Hierarchical cluster analysis (HCA) was employed to reveal the similarities based on leaf morphology and epidermal characters of the investigated species.

Results: Basal leaf of these species can be terete or flat, and it is triangle, flat, or circular in transverse section. Anticlinal wall patterns of the leaf epidermal cells were straight and sinuous, and only three species had epidermal hairs. Shape of long cells varies, ranging from quadrangular to irregular. HCA revealed that the 14 species could be divided into two groups. Group A was arranged into three subgroups (A1, A2 and A3), based on the Euclidean distance of 6.96. Subgroup A1 consisted of three species with indumentum; subgroup A2 had four species with sinuous type anticlinal walls; and subgroup A3 comprised of two species with a fistulose basal leaf. Group B included five species with short cells.

Conclusions: Leaf morphology and epidermal characters did not differ significantly among populations of the same species in Gagea, whereas they differ significantly among species. Thus, leaf morphology and epidermal characters provide diagnostic information for differentiating G. nigra and G. filiformis; G. altaica, G. jensii and G. alberti, which are morphologically similar species.

Background: Morphology, hosts, and collecting sites of fungi assessed from herbarium material of special interest deserve to be brought to the attention of mycologists.

Results: Specimens of Lopadostoma and Oligostoma deposited at ZT are briefly described and listed to expand the knowledge about their distribution. Three yet unmentioned Rosellinia collections are reported. One could be identified as R. mastoidiformis, a second as R. neblina; both are known only from the type collections. The third one seems to be a yet undescribed taxon and is formally described as R. schueppii.

Conclusions: These observations emphasize the importance of keeping fungal collections and highlight the importance of field work and contributions by early mycologists.

Background: The genus Camillea was created in 1849 from collections made in French Guiana with eight species included. Numerous species assigned to Camillea were subsequently discovered, especially in the forests of the Amazon basin, but new discoveries have not been reported from French Guiana since 1849. Recent fieldwork in French Guiana has begun to fill this gap by identifying five new species, most of which were collected in the vicinity of Saül village.

Results: Based on macro- and micromorphological study of their stromata, including SEM images of ascospore wall ornamentation, five new species were recognized, including C. cribellum, C. heterostomoides, C. nitida, C. rogersii and C. saulensis. Cultures could be obtained for C. heterostomoides and C. rogersii, and ITS and LSU sequences were obtained for all of the five new species. Camillea heterostoma and its variety microspora were shown to be conspecific. Provisional molecular phylogenetic analyses support the possible reinstatement of Hypoxylon melanaspis, currently regarded as merely an applanate form of C. leprieurii.

Conclusion: The current study is based on a relatively limited fieldwork in its duration and sampling area but was able to substantially increase the number of Camillea species known from French Guiana. This augurs an exceptional and still unknown diversity of the genus in this area and by extension in the adjacent neotropical forests.