Search Results (66)

As high-CBD cannabis (Cannabis sativa L.) gains legal and commercial relevance in the United States, studies evaluating how external inputs impact critical traits remain limited. This study investigates the effects of methyl jasmonate (MeJA), ammonium bicarbonate (AB), and the genetic source (mother plant identity) on the growth and secondary metabolite traits of indoor cannabis. Plants were treated with 1 mM MeJA and/or AB under controlled conditions, and key traits, such as plant height, chlorophyll content, biomass, trichome density, and cannabinoid concentration, were measured. The MeJA treatment led to a significant 32% increase in trichome density. However, it did not significantly alter CBD or THC concentrations. The AB treatment enhanced vegetative growth, increasing chlorophyll content and plant height while reducing CBD concentrations, but the biomass gains could compensate for the lower cannabinoid in the total production. An interaction between MeJA and AB altered the CBD content, suggesting that MeJA may mitigate AB’s negative effect on cannabinoid synthesis. The genetic source significantly influenced most of the measured traits, highlighting the role of the genotype in trait expression and the importance of clonal consistency. These findings highlight the complex dynamics of external inputs and genetic factors in cannabis production, emphasizing the need for further research to optimize cultivation strategies. Future studies should refine input combinations and doses to improve both yield and cannabinoid profiles. Full article

Grewia tembensis and Grewia trichocarpa inhabit dry tropical zones and arid environments, adapting to extreme climatic conditions and limited moisture supplies. Overall, Grewia L. possesses a significant variety of bioactive chemical constituents of great therapeutic importance. Indeed, for these species, precise morphological analyses are poor, and their detailed characterization is almost non-existent. This research attempts to investigate and compare the micromorphological traits of G. tembensis and G. trichocarpa species through scanning electron microscopy (SEM). Micromorphological characteristics of the leaf and fructiferous structures turned out to be highly effective in separating the two species, G. tembensis and G. trichocarpa, especially regarding the type, density, and distribution of trichomes on the lower and upper surfaces of the leaves, along with the stomatal and trichome types on the surfaces of the fruits. Statistical analyses using principal component analysis, t-tests, and hierarchical clustering conducted on micromorphological data of the leaves, flowers, and fruits showed considerable variation within samples of G. tembensis and samples of G. trichocarpa. On the basis of their morphological assessment characteristics, the samples of both species were distinct and clustered into separate groups. This study emphasizes the necessity of performing detailed morphological studies of species by means of an electron microscope and proves that the leaf features are important for separating species. Such morphological traits of trichomes would offer an efficient tool to distinguish the species. Within the findings, this suggests that such diagnostics are likely to be highly useful for species identification in Grewia, especially in cases where there are no fruits available. Full article

Nanchuan Dachashu (Camellia nanchuanica), an arboreal tea species from Chongqing, China, exhibits valuable germplasm characteristics and tea production quality. However, the morphological diversity and genetic basis of key traits, such as tree architecture, leaf anatomy, and ovary trichomes, within this natural population remain to be elucidated. In this study, we conducted a survey on 90 wild individuals from this population, with a special focus on ovary trichomes—an important taxonomic trait. Considerable variations were observed in tree architecture, leaf size and shape, and anatomical structures. Through association analysis, we identified the SNP locus Chr9_89939207 to be associated with the glabrous/hairy ovary trait. A KASP marker was subsequently developed based on this locus, which could accurately distinguish between glabrous and hairy ovary individuals of Nanchuan Dachashu, as well as differentiate this species from C. sinensis or other hairy ovary species. The SNP locus Chr9_89939207 resides in the exon of a predicted protein phosphatase 2C (PP2C) gene, CSS0003297, which potentially regulates ovary trichome development in tea plants. These results reveal extensive morphological variation within the Nanchuan Dachashu population, establish a molecular tool for the identification of valuable interspecific hybrids, and provide insights into the breeding and industrial applications of this germplasm. Full article

Airborne particulate matter (PM) is one of the most urgent urban environment problems in the world today. The urban ecosystem has been identified as a potentially promising solution to reduce the airborne PM based on the ability of plants to retain PM. Numerous studies have been conducted to explore the process and mechanism of atmospheric PM retention by plant leaves in the past. In this study, in order to better summarize previous research, particularly the impact of leaf traits on PM retention, and to provide guidance for the selection of tree species for nature-based urban PM solutions, a systematic review was carried out using the method recommended in the PRISMA, and a total of 49 articles were selected. It was found that: 1. Asian countries contribute the majority of the proportion (32, 65%). Following behind are European countries (13, 26.5%). The American countries contribute two cases. 2. Among all the tree species, Ginkgo biloba (16), Euonymus japonicus (11), Magnolia denudate (9), Styphnolobium japonicum (9), Magnolia grandiflora (8), and Prunus cerasifera (8) emerged as hot species in research. 3. Leaf area and shape emerged as the two most frequently discussed macro-indicators, while roughness, hairiness, and stomatal characteristics were the top three micro-indicators explored. 4. Roughness and stomata, respectively, play crucial roles in capturing larger PM particles and retaining fine and ultrafine PM through their recessed structures. Trichomes decrease the likelihood of particle resuspension and boosts the efficiency of PM retention. 5. Leaves with high rigidity and complex multi-faceted leaf shapes are typically presumed to exhibit higher PM retention efficiency for higher edge effects and increased interleaf turbulence. Furthermore, with rigidity and edge effects ensured, a larger leaf area is beneficial for retaining PM. Full article

The epidermal leaf patterns of plants exhibit remarkable diversity in cell shapes, sizes, and arrangements, driven by environmental interactions that lead to significant adaptive changes even among closely related species. The Solanaceae family, known for its high diversity of adaptive epidermal structures, has traditionally been studied using qualitative phenotypic descriptions. To advance this, we developed a workflow combining multi-scale computer vision, image processing, and data analysis to extract digital descriptors for leaf epidermal cell morphology. Applied to nine wild potato species, this workflow quantified key morphological parameters, identifying descriptors for trichomes, stomata, and pavement cells, and revealing interdependencies among these traits. Principal component analysis (PCA) highlighted two main axes, accounting for 45% and 21% of variance, corresponding to features such as guard cell shape, trichome length, stomatal density, and trichome density. These axes aligned well with the historical and geographical origins of the species, separating southern from Central American species, and forming distinct clusters for monophyletic groups. This workflow thus establishes a quantitative foundation for investigating leaf epidermal cell morphology within phylogenetic and geographic contexts. Full article

The commercial value of cucumbers is influenced by the presence of spines or trichomes on their fruit, while the trichomes found on other parts of the plant are essential for protecting the cucumber against a range of biotic and abiotic stresses. In our research, we identified a glabrous nwd mutant from EMS-induced cucumber (Cucumis sativus L.) mutant lines. This mutant displays a consistent glabrous phenotype across all plant organs. Upon analysis, it was revealed that the nwd mutation is governed by a lone recessive nuclear gene. The nwd plants show a significant reduction in both their photosynthetic capacity and chlorophyll a content when compared to the wild-type. Furthermore, there are notable changes in the antioxidant enzyme activities, soluble protein levels, and malondialdehyde content of the nwd mutant. Genotyping and MutMap approaches identified the CsNWD gene, encoding a VPS protein, as a candidate responsible for the glabrous trait. Transcriptome analysis indicated that 15 trichome-related genes exhibit significant expression changes in the nwd mutant, implying that CsNWD may regulate trichome development through interactions with these genes. This study contributes to the understanding of VPS proteins in trichome initiation and the underlying mechanisms of trichome development. Full article

Reduced defense against large herbivores has been suggested to be part of the “island syndrome” in plants. However, empirical evidence for this pattern is mixed. In this paper, we present two studies that compare putative physical and chemical defense traits from plants on the California Channel Islands and nearby mainland based on sampling of both field and common garden plants. In the first study, we focus on five pairs of woody shrubs from three island and three mainland locations and find evidence for increased leaf area, decreased marginal leaf spines, and decreased concentrations of cyanogenic glycosides in island plants. We observed similar increases in leaf area and decreases in defense traits when comparing island and mainland genotypes grown together in botanic gardens, suggesting that trait differences are not solely driven by abiotic differences between island and mainland sites. In the second study, we conducted a common garden experiment with a perennial herb—Stachys bullata (Lamiaceae)—collected from two island and four mainland locations. Compared to their mainland relatives, island genotypes show highly reduced glandular trichomes and a nearly 100-fold reduction in mono- and sesquiterpene compounds from leaf surfaces. Island genotypes also had significantly higher specific leaf area, somewhat lower rates of gas exchange, and greater aboveground biomass than mainland genotypes across two years of study, potentially reflecting a broader shift in growth habit. Together, our results provide evidence for reduced expression of putative defense traits in island plants, though these results may reflect adaptation to both biotic (i.e., the historical absence of large herbivores) and climatic conditions on islands. Full article

Black gram (Vigna mungo (L.) Hepper) is a pulses crop with good digestible protein and a high carbohydrate content, so it is widely consumed as human food and animal feed. Trichomes are large, specialized epidermal cells that confer advantages on plants under biotic and abiotic stresses. Genes regulating the development of trichomes are well characterized in Arabidopsis and tomato. However, little is known about trichome development in black gram. In this study, a high-density map with 5734 bin markers using an F₂ population derived from a trichome-bearing and a glabrous cultivar of black gram was constructed, and a major quantitative trait locus (QTL) related to trichomes was identified. Six candidate genes were located in the mapped interval region. Fourteen single-nucleotide polymorphisms (SNPs) or insertion/deletions (indels) were associated with those genes. One indel was located in the coding region of the gene designated as Scaffold_9372_HRSCAF_11447.164. Real-time quantitative PCR (qPCR) analysis demonstrated that only one candidate gene, Scaffold_9372_HRSCAF_11447.166, was differentially expressed in the stem between the two parental lines. These two candidate genes encoded the RNA polymerase-associated protein Rtf1 and Bromodomain adjacent to zinc finger domain protein 1A (BAZ1A). These results provide insights into the regulation of trichome development in black gram. The candidate genes may be useful for creating transgenic plants with improved stress resistance and for developing molecular markers for trichome selection in black gram breeding programs. Full article

Melon pest management relies on the excessive application of pesticides. Reducing pesticide spraying has become a global issue for environmental sustainability and human health. Therefore, developing a new cropping system that is sustainable and eco-friendly is important. This study found that melon seedlings irrigated with ultrafine water containing H₂ and O₂ (UFW) produced more root hairs, increased shoot height, and produced more flowers than the control irrigated with reverse osmosis (RO) water. Surprisingly, we also discovered that UFW irrigation significantly reduced aphid infestation in melons. Based on cryo-scanning electron microscope (cryo-SEM) observations, UFW treatment enhanced trichome development and prevented aphid infestation. To investigate whether it was H₂ or O₂ that helped to deter insect infestation, we prepared UF water enrichment of H₂ (UF+H₂) and O₂ (UF+O₂) separately and irrigated melons. Cryo-SEM results indicated that both UF+H₂ and UF+O₂ can increase the density of trichomes in melon leaves and petioles. RT-qPCR showed that UF+H₂ significantly increased the gene expression level of the trichome-related gene GLABRA2 (GL2). We planted melons in a plastic greenhouse and irrigated them with ultrafine water enrichment of hydrogen (UF+H₂) and oxygen (UF+O₂). The SPAD value, photosynthetic parameters, root weight, fruit weight, and fruit sweetness were all better than the control without ultrafine water irrigation. UFW significantly increased trichome development, enhanced insect resistance, and improved fruit traits. This system thus provides useful water management for pest control and sustainable agricultural production. Full article

Trichome plays an important role in heat dissipation, cold resistance, water absorption, protection of leaves from mechanical damage, and direct exposure to ultraviolet rays. It also plays an important role in the photosynthesis, transpiration, and respiration of plants. However, the genetic basis of trichome traits is not fully understood in wheat. In this study, wheat DH population (Hanxuan 10 × Lumai 14) was used to map quantitative trait loci (QTL) for trichome traits in different parts of flag leaf at 10 days after anther with growing in Zhao County, Hebei Province, and Taigu County, Shanxi Province, respectively. The results showed that trichome density (TD) was leaf center > leaf tip > leaf base and near vein > middle > edge, respectively, in both environments. The trichome length (TL) was leaf tip > leaf center > leaf base and edge > middle > near vein. Significant phenotypic positive correlations were observed between the trichome-related traits of different parts. A total of 83 QTLs for trichome-related traits were mapped onto 18 chromosomes, and each one accounted for 2.41 to 27.99% of the phenotypic variations. Two QTL hotspots were detected in two marker intervals: AX-95232910~AX-95658735 on 3A and AX-94850949~AX-109507404 on 7D. Six possible candidate genes (TraesCS3A02G406000, TraesCS3A02G414900, TraesCS3A02G440900, TraesCS7D02G145200, TraesCS7D02G149200, and TraesCS7D02G152400) for trichome-related traits of wheat leaves were screened out according to their predicted expression levels in wheat leaves. The expression of these genes may be induced by a variety of abiotic stresses. The results provide the basis for further validation and functional characterization of the candidate genes. Full article

Soil cyanobacterium, FBCC-A195 were isolated from the soil underneath the Jangnak Bridge, Republic of Korea. The FBCC-A195 was studied using light microscopy (LM), transmission electron microscopy (TEM), 16S rRNA, 16S–23S ITS, and ecological data. FBCC-A195 showed the circular cross-section of the trichome, broad mucilaginous envelopes, a swirl-like pattern of thylakoids inside the cell, and the lowest length/width ratio within the genus. In the 16S rRNA phylogeny, FBCC-A195 showed a sister relationship of Hormoscilla and belonged to the family Gomontiellaceae. The p-distance of FBCC-A195 ranged from 1.7% with H. pringsheimii to 12% with Komvophoron kgarii in the family. In the secondary structure of 16S–23S ITS, D1–D1’, Box-B, and V3 helix of FBCC-A195 were distinguished from those of other taxa in the Gomontiellaceae. Based upon morphological, ecological, and molecular traits, Katagnymene terrestris proved to be a unique and novel species of the Katagnymene. Full article

Nowadays, not only the roots, but also leaves and flowers of ginseng are increasingly popular ingredients in supplements for healthcare products and traditional medicine. The cultivation of the shade-loving crop, ginseng, is very demanding in terms of the light environment. Along with the intensity and duration, light direction is another important factor in regulating plant morphophysiology. In the current study, three lighting directions—top (T), side (S), or top + side (TS)—with an intensity of 30 ± 5 μmol·m⁻²·s⁻¹ photosynthetic photon flux density (PPFD) were employed. Generally, compared with the single T lighting, the composite lighting direction, TS, was more effective in shaping the ginseng with improved characteristics, including shortened, thick shoots; enlarged, thick leaves; more leaf trichomes; earlier flower bud formation; and enhanced photosynthesis. The single S light resulted in the worst growth parameters and strongly inhibited the flower bud formation, leading to the latest flower bud observation. Additionally, the S lighting acted as a positive factor in increasing the leaf thickness and number of trichomes on the leaf adaxial surface. However, the participation of the T lighting weakened these traits. Overall, the TS lighting was the optimal direction for improving the growth and development traits in ginseng. This preliminary research may provide new ideas and orientations in ginseng cultivation lodging resistance and improving the supply of ginseng roots, leaves, and flowers to the market. Full article

Macroevolutionary patterns in the association between plant species and their herbivores result from ecological divergence promoted by, among other factors, plants’ defenses and nutritional quality, and herbivore adaptations. Here, we assessed the performance of the herbivores Lema trilineata daturaphila, a trophic specialist on Datura, and Spodoptera frugiperda, a polyphagous pest herbivore, when fed with species of Datura. We used comparative phylogenetics and multivariate methods to examine the effects of Datura species’ tropane alkaloids, leaf trichomes, and plant macronutrients on the two herbivores´ performances (amount of food consumed, number of damaged leaves, larval biomass increment, and larval growth efficiency). The results indicate that species of Datura do vary in their general suitability as food host for the two herbivores. Overall, the specialist performs better than the generalist herbivore across Datura species, and performance of both herbivores is associated with suites of plant defenses and nutrient characteristics. Leaf trichomes and major alkaloids of the Datura species are strongly related to herbivores’ food consumption and biomass increase. Although hyoscyamine better predicts the key components of the performance of the specialist herbivore, scopolamine better predicts the performance of the generalist; however, only leaf trichomes are implicated in most performance components of the two herbivores. Nutrient quality more widely predicts the performance of the generalist herbivore. The contrasting effects of plant traits and the performances of herbivores could be related to adaptive differences to cope with plant toxins and achieve nutrient balance and evolutionary trade-offs and synergisms between plant traits to deal with a diverse community of herbivores. Full article

Satureja pilosa Velen., S. coerulea Janka and S. kitaibelii Wierzb. ex Heuff. are Balkan endemic species, and they are distributed in restricted territories, primarily found in dry grasslands, rocky slopes, and stony habitats. This study presents the results of the first embryological and micromorphological analyses of three Satureja species (S. pilosa, S. kitaibelii, and S. coerulea) from the Bulgarian flora. The aim of this study was to establish the features of the male and female reproductive sphere, as well as surface characteristics of leaves, stem, and calyx in order to understand the mode of reproduction, character, size and state of species populations and delimitation. For the embryological study, flowers and flower buds in different developmental stages were collected from plants of natural populations and treated with the classic paraffin method. Reproductive capacity was assessed using the following approaches: (1) acetocarmine test for pollen viability, (2) tetrazolium test (TTZ) for seed viability, and (3) germination test. The surfaces characteristics of leaves, stem, and calyx were analyzed by scanning electron microscopy (SEM). As a result, the study revealed the structures of the male (M) and female (F) generative spheres as well as the processes of gamete development, pollination, and endosperm and embryo formation. It was found that the three Satureja species exhibited a high pollen viability but low seed viability and germination. The SEM analysis showed both common and distinct micromorphology features regarding epidermis, calyx and stem surfaces among the three Satureja species. Notably, the S. coerulea surfaces (leaves, calyx, stem) were clearly distinguishable from the other two Satureja species. Regarding the nutlet surfaces, it was observed that the exocarp surfaces of S. coerulea and S. kitaibelii have a reticulate convex type surface and comprise two types of cells: (1) highly bulging, bubble-like cells; and (2) flat cells with numerous striations. On the other hand, the exocarp of S. pilosa displayed rectangular or polygonal shapes without bubble-like cells, and it had a tabular to slightly convex type surface. Additionally, nutlets (seeds) of both S. coerulea and S. pilosa exhibited distinct papilla formations resembling non-glandular trichomes seen on the ends of the nutlets for S. coerulea and over the entire surface for S. pilosa. The characteristics of the embryological structures and processes, along with the absence of apomixis, characterized the three studied Satureja species as sexually reproducing. The established balanced processes and stable structures contribute to their high reproductive potential and population stability. However, these traits may also decrease their adaptability to environmental changes. Full article

Leaf wettability, the affinity of a leaf surface to water droplets, affects the interactions between leaves and external environments. This study aimed to determine the interspecific and seasonal variabilities of leaf wettability across 30 common landscape plants, and their relationships with leaf functional traits, surface micromorphology and rainfall interception in Hefei city, China. Results indicated that leaf wettability was species-specific, and the adaxial and abaxial contact angles ranged from 63° to 134° and 66° to 134°, respectively, with the adaxial surface proving more wettable. Leaf wettability gradually increased from spring to winter. Classification of life forms revealed that there were no significant wettability differences among trees, shrubs and herbs, and between evergreen and deciduous plants, but deciduous plants’ wettability increased more significantly in winter. Leaf wettability was not significantly correlated with any leaf functional traits. Single surface microscopic parameters also had low correlations with leaf wettability. Instead, the low-wettability species were found to possess more prominent epidermis cells, dense waxy layers or trichomes on leaf surfaces. Leaf wettability was the best predictor of surface rainwater storage within all functional traits. Our results highlighted that leaf wettability was variable between different species and growth periods due to micromorphological differences, and significantly affected rainfall interception at the leaf scale, which may have great significance for evaluating plant hydrological function in urban areas. Full article