Stomatal Distribution Research Articles

Pharmacognostic Standardization and Chemical Study of Euphorbia nutans Lag. Euphorbiaceae

Aims: This study was designed to set macro/micro morphological standards, phytochemical and physicochemical parameters for the identification of E. nutans, a traditional remedy for the management of many disesases. Study Design: To establish pharmacognostic standards for proper identification of E. nutans and also study its phytochemicals using Gas Chromatography coupled to Mass Spectrometry (GC-MS). Place and Duration: This work was undertaken at the Department of Pharmacognosy and Natural Medicine, Faculty of Pharmacy, University of Uyo, Uyo, Nigeria for three month spanning from April through June, 2022. Methodology: Examination of microscopic characters, venation, chemomicroscopy, micromeritic properties, fluorescence analysis and phytochemical profiling using Gas Chromatography-Mass Spectrometry (GC-MS) were carried out. Results: Epidermal cell shapes were irregular with undulate-sinuous anticlinal walls. Stomatal distribution was amphistomatic with anisocytic and anomocytic stomata on both surfaces. Areolation was quadrangular, linear and biforked vein termination. The fluorescence characteristics showed the presence of different colours supporting the presence of various phytoconstituents for both leaf and stem. The flow properties for both leaf and stem were poor while GC-MS analysis of the dichloromethane extracts revealed lupeol (64.05%), 2-methylhexacosane (9.37%), stigmasterol (4.16%) and campesterol (1.29%) as major components in the leaf while campesterol (0.67%), stigmasterol (2.15 %), beta.-sitosterol (6.22%), lupeol (9.85%) and vitamin E (1.05%) for the stem extract. Conclusion: The results of the study could be useful for correct identification, standardization and preparation of monograph.

Microscopic, Micromeritic and Phytochemical Analysis of the Leaves of Pseuderanthemum maculatum (G. Lodd.) I. M. Turner, A Plant with Potential Pharmacognistic Uses

Background: Pseuderanthemum maculatum, Pseuderanthemum maculatum (G.Lodd.) I.M.Turner [previously Pseuderanthemum carruthersii (Seem.) Guillaumin var. carruthersii] is an ornamental plant with potential pharmacognostic uses in the management of hypertension and cancers. There hadn’t been much work done on this plant previously hence making the current research work very much significant. Methods: The leaves were collected, identified, air dried, pulverized, weighed and subjected to evaluation parameters using standard procedures. GC-MS analysis was also carried out on the dichloromethane extract of the leaf. Results: The results showed that the stomatal distribution was hypostomatic with diacytic stomatal type. Stomatal index was 23.12% and the stomatal number was 60 (69.9 ± 2.65)86. Flow rate of the leaf was poor with the bulk volume of 32.30 ± 1.04, tapped volume of 21.8 ± 0.76, bulk density of 0.32 ± 0.02, tapped density of 0.46 ± 0.02, angle of repose 42.65°, Carr's index of 31.06% and Hausner's ratio of 1.45 ± 0.03. The chemomicroscopy and fluorescence analyses revealed characteristic features for the drug. The water-soluble, methanol-soluble, ethanol-soluble extractive values were 20.67 %w/w, 11.67 %w/w and 11.33 %w/w respectively. The moisture content of the leaf powder was 9.84%w/w. The total ash, acid-insoluble and water-soluble ash values were 6.72%w/w, 1.34%w/w and 16.17%w/w respectively. The GC-MS analysis revealed the presence of 11 chemical constituents with phytochemicals such as hexanoic acid, benzoic acid, undecenoic acid, heptanoic acid and Eicosane which are of useful pharmaceutical importance. Conclusion: These data obtained from the pharmacognostic studies provides information about the identity, purity and quality of Pseuderanthemum maculatum.

Cuticular morphology of Schinus L. and related genera

Abstract The Anacardiaceae are a characteristic angiosperm family of the Neotropics where they comprise ~32 genera and 200 species (~80 genera and 800 species globally). Among Neotropical Anacardiaceae genera, Schinus has the greatest species richness with 42 species distributed from tropical latitudes of Brazil and Peru south to the temperate steppe, matorral, and Valdivian temperate forest communities of Patagonia. Previous studies have found some anatomical and morphological leaf traits (e.g. simple vs. compound leaf organization) useful in characterizing lineages within Schinus, but also document traits that are homoplastic within the genus (e.g. stomatal distribution) and convergent among Schinus and its close relatives Lithrea and Mauria (e.g. mesophyll arrangement). Here, we present a survey of leaf cuticular traits in 53 species of Schinus and its closest relatives Lithrea, Mauria, and Euroschinus based on characters observed with scanning electron and optical light microscopy. We use ordinated Bray–Curtis distances based on 18 characters and 2D nonmetric multidimensional scaling to show that cuticular morphology resolves the three most diverse genera, Euroschinus, Mauria, and Schinus, but does not resolve intrageneric sections of Schinus. We propose that a distinctive acuminate gland type occurring only within Euroschinus may constitute a potential synapomorphy for this genus. Within Schinus, we find inconsistency in stomatal distribution among specimens of a single species, among species of a single section, and between sections of the genus, and suggest that current evidence is insufficient to implicate either phenotypic plasticity or homoplasy as the causative mechanism of this variation.

Pharmacognostic Study and Phytochemical Profilling of Dichloromethane Extracts of the Leaf and Stem of Vernonia conferta Benth and Vernonia colorata Drake Asteraceae

Aims: The study determines various taxonomic, pharmacognostic and phytochemical standards helpful to ensure the identity, purity, safety and efficacy of Vernonia colorata and Vernonia conferta. Study Design: To study these two species of Vernonia for their epidermal cell shapes, stomatal types and distribution, trichome types, chemomicroscopic and fluorescence characters, flow properties, ash values, extractive solvents and phytoconstituents of dichlormethane fractions using GC-MS. Place and Duration: This study was conducted at the Department of Pharmacognosy and Natural Medicine, Faculty of Pharmacy, University of Uyo, Uyo from June 2023 to December 2023. Methodology: The pharmacognostic characterization was determined following the guidelines given by the World Health Organization (WHO). Parameters determined included microscopy, powder microscopy, chemomicroscopy, micromeritic properties, ash values, extractive values, fluorescence analysis while phytochemical analysis was done using Gas Chromatography coupled to Mass Spectrometer. Results: Epidermal cell shapes were both irregular with undulate and sinuous anticlinal wall pattern for both V. colorata and C. conferta respectively. Stomatal distribution was hypostomatic with paracytic stomata on the abaxial surface for C. conferta while amphistomatic with anomocytic stomata in V. colorata. Stomatal index was highest in V. conferta with 27.31% and least in V. colorata 21.52%. Unicellular trichomes were observed in V. colorata and V. conferta epidermal surfaces. The chemomicroscopic study revealed the presence of lignin, starch, cellulose, oils, calcium oxalate crystals, mucilage and protein for both leaf and stem respectively. The fluorescence characteristics showed the presence of different colours supporting the presence of various phytoconstituents for both leaf and stem. The quantitative epidermal studies, chemomicroscopic and fluorescence characteristics revealed characteristic features for the drug. The flow properties for both leaf and stem were poor. The total ash values for both leaf and stem ranges between (2.40 – 9.30 and 10.60 – 11.06), acid-insoluble ash values were low, moisture contents were between 8 - 14%w/w, water and methanol extracted more constituents. In total, 12 chemical constituents each were recorded for the leaves of V. colorata and V. conferta, respectively, while 10 and 12 were also recorded for the dichloromethane stem extracts of V. colorata and V. conferta, respectively. Conclusion: This study is useful in pharmacognostic standardization of Vernonia colorata and Vernonia conferta.

Foliar epidermal micro-morphology of selected brinjal varieties: A study on leaf surface characteristics

Studies on the leaf epidermal morphological characteristics were conducted on the three varieties of brinjal (Solanum melongena L.) belonging to the family Solanaceae. The varieties used in the study were Bhavani Gold, Purple Round and Haritha. Fresh mature brinjal leaves were randomly selected from the three experimental genotypes, and the foliar epidermal features were studied by using light microscopy and SEM imaging. Measurements were taken with an ocular and stage micrometer using 10X and 40X magnifications. The photographs were taken from mounted slides. The stomatal count and each measurement represent the average of ten readings. The upper and lower epidermal surfaces of leaf were studied for stomatal features including, stomatal distribution, stomatal type, stomatal index, stomatal pore length, stomatal pore width, guard cell length, guard cell width, subsidiary cell length and width, epidermal cell type, epidermal cell length and width, trichome type, trichome length and width. Amphistomatous, anisocytic, and with more stomata on the lower epidermal surface than the upper epidermal surface were present in all leaf varieties. On the leaves, the abaxial stomatal index ranged from 68.19 mm-2 (Bhavani Gold) to 56.67 mm-2 (Purple Round) to 58.8 mm-2 (Haritha). While on the adaxial surface, it varied from 59.67 mm-2 (Bhavani Gold), 53.46 mm-2 (Purple Round) and 56.67 mm-2 (Haritha). The three varieties of this study exhibited similarities in the pattern of epidermal cell on the adaxial and abaxial surfaces and were irregular in shape. Among the three varieties epidermal cell become irregular in outline and trichomes were present on both leaf surfaces. It becomes stellate, non-glandular, glandular and 8-12 in number. The highest trichome length was obtained in Bhavani Gold (63 μm) followed by Haritha (57.5 μm) and Purple Round (43 μm) on the upper epidermis. On the lower epidermal region maximum length was obtained in Bhavani Gold (65.5 μm) followed by Haritha (53 μm) and Purple Round (44 μm).

Carbon nanoparticle exposure strengthens water-relation parameters by stimulating abscisic acid pathway and aquaporins genes in rice

Mechanism of action and molecular basis of positive growth effects including yield increase due to carbon nanoparticle (CNP) treatment in rice plants is dissected here. CNP at 500 -750 µg/mL were found to be the optimum dosages showing best seedling growth. CNP treatment resulted increase in stomata size, stomatal conductance and water use efficiency along with low relative humidity, decrease in stomata frequency and internal CO2 concentration. CNP-coupled with water uptake was found to be endocytosis mediated, although CNP uptake was not affected by endocytosis inhibitor application in roots. Genomic analysis resulted major involvement of ABA pathway and stomata size and frequency genes in Arabidopsis and rice. Elevated endogenous ABA in rice seedlings and flag leaves along with increased expression of ABA biosynthetic genes in Arabidopsis and rice AtNCED3, AtNCED6, OsNCED1 confirmed increased ABA synthesis. Negative regulators of ABA pathway, OsSNRK2 down-regulation and up-regulation of stomagen (OsEPFL9) reconfirmed ABA's involvement. CNP treatment exerted cold tolerance in seedlings and water stress tolerance in reproductive stage. CNP treatment under water withheld condition resulted water stress tolerance by maintaining lower stomatal conductance, transpiration rate and higher relative water content. Increased ABA (OsSNRK1, OsSNRK2) and aquaporin (OsPIP2–5 and OsPIP1–3) genes’ expressions could explain the better water stress tolerance in rice plants treated with CNP. Altogether, due to thermomorphogenesis, down-regulation of Phytochrome B transcript resulted altered the ABA pathway and stomatal distribution with size (Graphical Abstract). These changes resulted improved water relation parameters and water use efficiency (WUE) showing improvement in yield. Detailed mechanism of action of CNP in abiotic stress tolerance can be exploited using nano-agriculture at field level.

The relationship between atmospheric particulate matter, leaf surface microstructure, and the phyllosphere microbial diversity of Ulmus L.

BackgroundPlants can retain atmospheric particulate matter (PM) through their unique foliar microstructures, which has a profound impact on the phyllosphere microbial communities. Yet, the underlying mechanisms linking atmospheric particulate matter (PM) retention by foliar microstructures to variations in the phyllosphere microbial communities remain a mystery. In this study, we conducted a field experiment with ten Ulmus lines. A series of analytical techniques, including scanning electron microscopy, atomic force microscopy, and high-throughput amplicon sequencing, were applied to examine the relationship between foliar surface microstructures, PM retention, and phyllosphere microbial diversity of Ulmus L.ResultsWe characterized the leaf microstructures across the ten Ulmus lines. Chun exhibited a highly undulated abaxial surface and dense stomatal distribution. Langya and Xingshan possessed dense abaxial trichomes, while Lieye, Zuiweng, and Daguo had sparsely distributed, short abaxial trichomes. Duomai, Qingyun, and Lang were characterized by sparse stomata and flat abaxial surfaces, whereas Jinye had sparsely distributed but extensive stomata. The mean leaf retention values for total suspended particulate (TSP), PM2.5, PM2.5-10, PM10-100, and PM> 100 were 135.76, 6.60, 20.10, 90.98, and 13.08 µg·cm− 2, respectively. Trichomes substantially contributed to PM2.5 retention, while larger undulations enhanced PM2.5-10 retention, as evidenced by positive correlations between PM2.5 and abaxial trichome density and between PM2.5-10 and the adaxial raw microroughness values. Phyllosphere microbial diversity patterns varied among lines, with bacteria dominated by Sediminibacterium and fungi by Mycosphaerella, Alternaria, and Cladosporium. Redundancy analysis confirmed that dense leaf trichomes facilitated the capture of PM2.5-associated fungi, while bacteria were less impacted by PM and struggled to adhere to leaf microstructures. Long and dense trichomes provided ideal microhabitats for retaining PM-borne microbes, as evidenced by positive feedback loops between PM2.5, trichome characteristics, and the relative abundances of microorganisms like Trichoderma and Aspergillus.ConclusionsBased on our findings, a three-factor network profile was constructed, which provides a foundation for further exploration into how different plants retain PM through foliar microstructures, thereby impacting phyllosphere microbial communities.

Studies on Various Taxonomic, Pharmacognostic and Phytochemical Properties of Sanchezia speciosa Leonard Acanthaceae

Sanchezia speciosa Leonard, Acanthaceae is used as ornamental plant. It used in folklore medicine in the management of pain, anti-microbial and insecticide. An investigation was carried out to evaluate the various taxonomic, pharmacognostic and phytochemical standards to ensure the identity, purity, safety and efficacy of the medicinal plant, S. speciosa. Various observations were recorded which included microscopy, micromeritics, fluorescence, chemomicroscopy, soluble extractive values, moisture contents and phytochemical analysis. The results indicated that the epidermal shapes were both polygonal on the adaxial and abaxial surfaces. Stomatal distribution was amphistomatic with anisocytic and diacytic stomata on the adaxial and abaxial surface, respectively. Stomatal index was 21.47% on the adaxial surface and 15.43% on the abaxial surface. Micromeritics results for the leaf powder were bulk volume of 25.33± 0.408, tapped volume of 19.00± 0.00, bulk density of 0.40± 0.006, tapped density of 0.53± 0.021, Hausner’s ratio of 1.34± 0.037, Carr’s index of 25.00± 2.550 and angle of repose of 43.07°. The micromeritics indicated a passable flow. The chemo microscopy indicated presence of lignin, mucilage and starch. Fluorescence properties showed different colours under different ultraviolet lights. The water-soluble, methanol-soluble, ethanol-soluble extractive values were 14.7% w/w, 4.3% w/w and 5.0% w/w, respectively. Moisture content was 8.5% w/w. Total ash, acid-insoluble and water-soluble ash values were 20.0 % w/w, 2.0% w/w and 4.2% w/w, respectively. GC-MS of methanol extract revealed the total of 39 phytochemicals with over 5 prominent peaks having higher area% which include hexadecanoic acid methyl ester (2.64%), 9,12,15-octadecatrienoic acid methyl ester (4.77%), phytol (9.98%), 9,12,15 octadecatrienoic acid (12.97%), Stigmasterol (2.00%) and Squalene (28.16%). Other compounds are glycerin (5.83%), n-hexadecanoic acid (2.85%) and 9 octadecenamide (2.18%). Many of them possess good pharmacological properties. The data generated from the present study would help to authenticate S. speciosa and also affirm its folklore use in traditional medicine which has potential for further development into drug product.

An Inverse Scaling Relationship between Stomatal Density and Mean Nearest Neighbor Distance: Evidence from a Photinia Hybrid and One of Its Parents.

Stomata are involved in transpiration and CO2 uptake by mediating gas exchange between internal plant tissues and the atmosphere. The capacity for gas exchange depends on stomatal density (SD), stomatal size, and pore dimensions. Most published work on stomatal quantification has assumed that stomatal distribution and stomatal density are spatially homogeneous across the leaf, but this assumption has been seldom tested. We selected 32 leaves from a Photinia hybrid, Photinia × fraseri 'Red Robin', and one of its parents, P. serratifolia. For each leaf, the leaf surface was divided into three or four equidistant layers along the apical-basal axis, and, in each layer, two positions, one closer to the midrib and the other closer to the leaf margin, were further selected. We calculated SD and mean nearest neighbor distance (MNND) for each lamina section and tested the scaling relationship between SD and MNND of the sampled stomatal centers using reduced major axis protocols. In addition, we calculated the stomatal aggregation index (SAI) for each lamina section to examine the spatial arrangement of stomata at the given size of field of view of 1.2 mm × 0.9 mm. We observed that SD decreased from the lamina apex towards the base for central lamina areas but varied little at leaf margins. An inverse scaling relationship between SD and MNND was observed for both species. This relationship could be used for SD estimation using the rapidly estimated trait, MNND. SAI did not vary significantly throughout leaf lamina, and the numerical values of SAI for all fields of view were greater than one, which indicates significant spatial repulsion between stomata. The study suggests that SD varies across leaf lamina to fine-tune plant water use and maximize carbon gain. However, spatial structures of stomata from different lamina sections exhibit similar patterns (i.e., spatial inhibition between stomata at small scales), probably due to hierarchical leaf vein patterns.

Characteristics and Evolution of Leaf Epidermis in the Genus Amana Honda (Liliaceae)

Amana, commonly known as ‘East Asian tulips’, has recently been found to harbor cryptic diversity due to recent field work and systematic investigations. In this study, we included 64 populations from all 12 Amana species and performed microscopic observations of their epidermal morphology. The leaf epidermis stomatal distribution of Amana can be characterized into three types: dense stomata (>10/per view or 263/mm2), sparse stomata (<10/per view or 263/mm2), and stomata absent. The epidermal cells of Amana can be characterized into four types: rectangular, long rectangular, nearly rectangular, and rhombic. The anticlinal wall morphology of the epidermal cells can be characterized into three types: linear, wavy, and nearly linear with mixed shallow waves. All the results were helpful for classification of Amana species. According to the reconstruction of ancestral characters analyses, the common ancestor of Amana is most likely to have leaves with dense stomata on both sides, and epidermal cells that have linear vertical walls.

Drought dampens the positive acclimation responses of leaf photosynthesis to elevated [CO2] by altering stomatal traits, leaf anatomy, and Rubisco gene expression in Pyrus

The responses of Chinese pear plantations to rising atmospheric CO2 concentration ([CO2]) and drought are crucial for accurately estimating pear production and forest carbon sink of China under future climate change. Here, we investigated the effect of CO2 enrichment on plant growth and leaf photosynthesis of Chinese pear trees grown under full irrigation and different levels of drought. We identified that leaf photosynthetic capacity and stomatal conductance increased by high [CO2] acclimation. However, such positive effects disappeared when drought occurred, especially under moderate and severe drought. This down-regulation of high [CO2] acclimation responses in leaf photosynthesis by drought was mainly caused by the decline in stomatal diffusional efficiency, thinner mesophyll tissues and smaller mesophyll cells. The decrease of stomatal diffusional efficiency was further caused by the reduced stomatal density and decreased regularity of stomatal distribution pattern under drought. Moreover, the down-regulation of those positive acclimation responses was relevant with the declines of carboxylation and photochemical efficiency of Rubisco, which was confirmed by the down-regulated expression levels of Rubisco coding genes. Overall, our results demonstrated that drought dampened the positive acclimation responses of leaf photosynthesis to elevated [CO2] by modifying stomatal morphology and distribution, leaf anatomy, and Rubisco gene expression. Therefore, under future climate change where CO2 enrichment is coupled with higher frequency of drought events, drought limitations should be incorporated into the current coupled climate-carbon models to avoid overestimation of the positive responses of Chinese pear plantations to elevated [CO2] and to accurately predict forest carbon sequestration.

Elevated CO2 concentration regulate the stomatal traits of oilseed rape to alleviate the impact of water deficit on physiological properties

There is a limited understanding of how stomatal distribution and structure affect photosynthesis under elevated CO2 concentrations (e[CO2]) and variable soil water environments. This study investigated the effects of e[CO2] on stomatal morphology and distribution, gas exchange and growth parameters of oilseed rape plants under water deficit [soil moisture decreased from 80% field capacity (FC) (W; full irrigation) to 60% FC (D1), 40% FC (D2), and < 35% FC (D3)] and re-watering conditions in growth chambers with [CO2] controlled at 400 µmol mol−1 (a[CO2]) or 800 µmol mol−1 (e[CO2]). e[CO2] had a strong CO2 fertilization effect on the net photosynthetic rate (An) and growth of plants under water deficit. Under a[CO2], stomatal density and aperture on the adaxial leaf surface increased when soil moisture decreased from W to D1, while the stomatal aperture and regularity of the spatial distribution pattern of stomata decreased with decreasing soil moisture. Stomatal conductance (gs) were 47.1% and 26.1% capacity of anatomically determined maximum anatomical conductance (gsmax) with W under a[CO2] and e[CO2], respectively. e[CO2] enhanced plant recovery after re-watering through modifying stomatal traits. This study offers insights into the trade-off between stomatal traits and gas exchange for adapting plants to future climates.

Rapid evaluation of leaf photosynthesis using a closed-chamber system in a C4 plant, sugarcane

ABSTRACT To accelerate research on improving sugarcane biomass production, a rapid phenotyping method for individual leaf photosynthetic rates is required. Recently, a closed-type measurement system, which is faster, lighter, and less expensive than conventional open-type systems, has been developed and utilized for C3 crops. For future utilization of the system in phenotyping photosynthetic rates in sugarcane, which exhibits higher photosynthetic rate than C3 crops, diurnal changes and genotypic differences were measured simultaneously using an open-type and a closed-type system to verify the accuracy of the measurements in assessing environmental responses and genetic variation. As the relative root-mean-square error, a regression accuracy between the measurements with two systems, was <20% when evaluating diurnal changes and genotypic differences, closed system accurately evaluated photosynthetic rates in multiple samples. Overall, the measured values with the closed system tended to be higher than those with the open system, especially in high values above 30 µmol m−2 s−1. The reason for this was presumably not leaf morphology, such as stomatal distribution, but a fundamental difference in the measurement systems (steady-state values for the open system and instantaneous values for the closed system). The open system required 5–7 min to measure a single record, whereas the closed system could measure at <40 s per record. Although it would be desirable to develop a regression equation using measurements involving the open system for each cultivar to examine physiological response in detail, we conclude that the closed system has greater potential for use in phenotyping sugarcane photosynthesis.

Stomatal distribution pattern for 90 species in Loess Plateau – Based on replicated spatial analysis

Stomata are the valves controlling carbon and water exchange between plant leaves and the atmosphere. Stomatal position changes throughout the whole growth of leaves, and the position is gradually fixed until the leaves mature, whether stomatal spatial distributions exhibit clear patterning remains unclear. In this study, we measured stomatal density and stomatal position of 90 widespread plants from the Loess Plateau, quantifying the spatial patterns of stomatal distribution using replicated spatial point pattern analysis. The results showed that the stomatal distribution pattern was similar in all plants except five species (Ginkgo biloba, Festuca glauca, Hemerocallis fulva, Hylotelephium spectabile and Kochia scoparia). Stomatal density, aggregation and uniform distribution were slightly affected by phylogeny and depended on spatial scale of analysis. At small spatial scales (0–60 μm), were regularly distributed but at large spatial scales (60–400 µm) they were randomly distributed. Stomatal density was negatively correlated (p < 0.001) with the proportion of randomly distributed and positively correlated (p < 0.001) with the proportion of stomatal aggregated distributed, and no significant effect on the proportion of stomatal uniform distribution. These results highlight the linkages between stomatal distribution and phylogeny, which may provide reference for future optimization of transpiration models.

Roles of type II H+-PPases and PPsPase1/PECP2 in early developmental stages and PPi homeostasis of Arabidopsis thaliana.

The regulation of intracellular pyrophosphate (PPi) level is crucial for proper morphogenesis across all taxonomic kingdoms. PPi is released as a byproduct from ~200 metabolic reactions, then hydrolyzed by either membrane-bound (H+-PPase) or soluble pyrophosphatases (PPases). In Arabidopsis, the loss of the vacuolar H+-PPase/FUGU5, a key enzyme in PPi homeostasis, results in delayed growth and a number of developmental defects, pointing to the importance of PPi homeostasis in plant morphogenesis. The Arabidopsis genome encodes several PPases in addition to FUGU5, such as PPsPase1/PECP2, VHP2;1 and VHP2;2, although their significance regarding PPi homeostasis remains elusive. Here, to assess their contribution, phenotypic analyses of cotyledon aspect ratio, palisade tissue cellular phenotypes, adaxial side pavement cell complexity, stomatal distribution, and etiolated seedling length were performed, provided that they were altered due to excess PPi in a fugu5 mutant background. Overall, our analyses revealed that the above five traits were unaffected in ppspase1/pecp2, vhp2;1 and vhp2;2 loss-of-function mutants, as well as in fugu5 mutant lines constitutively overexpressing PPsPase1/PECP2. Furthermore, metabolomics revealed that ppspase1/pecp2, vhp2;1 and vhp2;2 etiolated seedlings exhibited metabolic profiles comparable to the wild type. Together, these results indicate that the contribution of PPsPase1/PECP2, VHP2;1 and VHP2;2 to PPi levels is negligible in comparison to FUGU5 in the early stages of seedling development.

Taxonomic Significance of Foliar and Stem Anatomy in the Delimitation of Piptadeniastrum africanum (Hook.F.) Brenan and Cathormion altissimum (Hook.F.) Hutch. &amp; Dandy

The current monotypic status of the genus Piptadeniastrum Brenan is reasonably challenged as Cathormion altissimum is claimed to be closely related to Piptadeniastrum africanum – the only species in the genus – by some indigenous people of Bayelsa State. This work systematically examines this claim by studying some aspects of the foliar and stem anatomy of P. africanum and C. altissimum. Leaf peels and stem sections were made and analyzed according to standard procedures. Anatomical characteristics considered include stomata distribution, stomatal Index, type of stomata, the shape of leaf epidermal cells and anticlinal walls, the outline of the stem, and the arrangement of vascular bundles. Results showed that stomatal distribution in both plants was hypostomatic. Stomatal index and stomata type was 21.5% and mainly anomocytic, respectively, for P. africanum and 14.4% and primarily paracytic, respectively, for C. altissimum. Epidermal cell shape is irregular with undulating anticlinal walls in P. africanum, while epidermal cell shape is rectangular to polygonal with curved or straight anticlinal walls in C. altissimum. The outline of the stem is angular with four pronounced ridges and furrows in P. africanum, while the stem outline is wavy with very mild protrusions in C. altissimum. The differences in anatomical characteristics may justify the placement of these plants in different genera. Piptadeniastrum Brenan is monotypic.

Histological and Micromeritic Differences Between the Two Varieties of Lonchocarpus sericeus (Poir.) Kunth ex DC. (Fabaceae)

Purpose: Lonchocarpus sericeus (Poir.) kunth ex DC. (Fabaceae) is a tropical plant used in ethnomedicine as an analgesic, appetite stimulant, antibacterial and cytotoxic agent. This study aims to establish histological and micromeritic parameters as standards for the leaves of brown and white varieties. Methods: The leaves of both varieties were collected, dried under shade and pulverized. Microscopic evaluations were done on both the fresh and powdered samples. Micromeritic properties were determined for the plant organs collected. Carr’s index, angle of repose and Hausner’s ratio were calculated. Chemomicroscopic and fluorescence evaluations were also done on the powders. Results: The results obtained from the microscopy of the fresh leaves revealed hypostomatic stomatal distribution and anomocytic type of stomata for the brown variety and paracytic type of stomata for the white variety both on abaxial surfaces. The epidermal cell shapes for the abaxial and adaxial surfaces were both irregular. The stomatal number was found to be 36.9 ± 0.71 and 17.8 + 0.97 for the brown and white varieties respectively. The stomatal index was 8.13 %. and 7.45 % for the brown and white varieties respectively. The angle of repose for the brown and white varieties were 33.7 ± 0.72 and 40.05 ± 0.57 respectively. The chemomicroscopic result revealed that both leaves contained cellulose, mucilage, lignin, protein and starch. Conclusion: The results obtained from this study can be used to distinguish between the two varieties, and could also serve as pharmacopeial standards for quality assurance of the medicinal plant as a herbal drug. Keywords: Lonchocarpus sericeus, Carr’s index, Hausner’s ratio, micromeritic, histological

Pharmacognostic and Taxonomic Studies of the Leaf of Ageratum houstonianum Mill. (Compositae)

Ageratum houstonianum occurs as a common agricultural weed, it is managed in small and large cropping situation by tillage and can contribute to soil fertility as a waste mulch. The aim of this study was to employ the pharmacognostic and taxonomic parameters to evaluate the leaves of Ageratum houstonianum. The leaves were collected, identified, air dried, pulverized and subjected to microscopy, micromeritics, chemomicroscopy, fluorescence, soluble-extractive values, moisture content and ash values using standard procedures. The result obtained from the microscopy showed an irregular epidermal cell shape and a sinuous anticlinal wall pattern, anomocytic type of stomata, double armed trichome and amphistomatic stomatal distribution on both the abaxial and adaxial surfaces. The stomatal index for the abaxial surface was 11.6% and for the adaxial surface was 25.6%.The micromeritic evaluation of the powdered leaf revealed a Carr’s index of 25.23%, Hausner’s ratio of 1.33 and an angle of repose of 38.8o indicating a poor flow. The result for chemomicroscopy showed the presence of oils, protein, lignin, mucilage and calcium oxalate crystals. For moisture content, the result was 12.7%w/w, the Total ash value was 14%w/w, Acid-insoluble ash value was 0.7%w/w,water-soluble ash value was 7.7%w/w, methanol-soluble extractive value was 17%w/w, ethanol-soluble extractive value was 16%w/wand the water-soluble extractive value was 21%w/w. The data obtained from the pharmacognostic and taxonomic studies provided information for the identity, quality and purity of Ageratum houstonianum.

Pharmacognostic and Taxonomic Studies of Leaf and Stem of Launaea taraxacifolia (Willd) Amin Ex C. Jeffrey (Compositae)

Launaea taraxacifolia from the family Compositae is used in the treatment of diabetes mellitus, hypertention, cancer, malaria, bacterial infections and arthritis. The aim of this study was to evaluate pharmacognostic and taxonomic parameters such as microscopy, micromeritics, chemomicroscopy, fluorescence, soluble-extractive values and ash values of the leaves and stems of this plant. The plant was collected, identified, air-dried, weighed and subjected to evaluation using standard procedures. The results showed that, from microscopy: the stomatal distribution was amphistomatic and the stomatal type were anisocytic and anomocytic on the abaxial surface and anomocytic on adaxial surface with T-pieces on the stomata. The stomatal index was 18.7% on the abaxial surface and 11.9% on the adaxial surface. The stomatal number on the abaxial surface was 13.2 (15.6±0.55) 18.1 and 18 (26.5±2.08) 36 for adaxial surface. Results of the micromeritics properties of the powdered leaf and stem samples were bulk volume of 38.67±0.17 and 51.33±0.33, tapped volume of 29.83±0.17 and 34.0±0.00, bulk density of 0.26±0.00 and 0.20±0.00, tapped density of 0.34±0.00 and 0.29±0.00, angle of repose of 36⁰ and 43⁰, Carr’s index of 22.7% and 33.78%, Hausner’s ratio of 1.30±0.01 and 1.15±0.01. The micromeritics indicated that the powder had a fair flow and for chemomicroscopy the powder contained lignin, mucilage, oil and protein. The fluorescence properties determined revealed different colours under different ultraviolet lights. The water-soluble, methanol-soluble, ethanol-soluble extractive values were 35% w/w, 14% w/w and 16%w/w for leaf and 18% w/w, 8% w/w, and 9% w/w for stem respectively. The moisture content of the leaf and stem were 16% w/w and 11% w/w. Total, acid-insoluble and water- soluble ash values were 17.7% w/w, 1.3% w/w and 8.3% w/w for leaf and 6.3% w/w, 0.3% w/w and 4.7% w/w for the stem respectively. This data obtained from the pharmacognostic and taxonomic studies provide information for the identity, purity and quality of L. taraxacifolia.

KELAYAKAN HANDOUT STRUKTUR DAN FUNGSI JARINGAN TUMBUHAN DENGAN TAMBAHAN DISTRIBUSI STOMATA DAN LAJU TRANSPIRASI

This study aimed to determine the feasibility of handout of submaterial structure and function of plant tissue with additional information about the stomatal distribution and transpiration rate used as teaching material. The research method used a descriptive. The validation was conductive by 5 validators and the validator was divided into two, namely the instrument validator and the handout teaching material validator. The instrument validator consisted of 2 Biology Education lecturers at FKIP UNTAN and 1 high school biology teacher in senior high school grade XI pontianak. The handout teaching material validator consisted of 2 Biology Education lecturers at FKIP UNTAN and 3 biology teachers senior high school grade XI pontianak using the 2013 curriculum and school accreditation A. The assessment used 5 aspects and 10 criteria. The results of handout validation of structure and function of plant tissue submaterial in senior high school grade XI of teaching materials with additional information based on the stomatal distribution and the transpiration rate in six monocot plants obtained an average CVR and CVI results 0.99 categorized valid and feasible to be used in the learning process. However, further research was needed on the effectiveness of learning outcomes used handout teaching materials in the learning process.