Many plants provide us with food, medications, textiles and building materials, while others enhance the beauty of our surroundings. In addition to these beneficial plants, there are several plants that are harmful. Poisonous plants are those that contain compounds capable of causing varying degrees of discomfort, adverse physical and chemical effects, or even death in humans and animals when consumed or otherwise come into touch with the human body (Fuller and Mcclintock, 1986). Poisonous plants contain harmful chemicals in quantities that can cause sickness or demise in animals and humans. The toxic components of these plants can be present in the root, fruit bulb, stem, pollen branch, seed leaf, rhizome, flower, nectar or sap, which may vary from species to species. Plant ingredients such as photosensitising chemicals, minerals, glycosides, oxalates, proteins, terpenes, alkaloids, amino acids, tannins, phytotoxins and phenolics are all toxicologically important and known as secondary metabolites (Konyar et al., 2014). With the accumulation of secondary metabolites in plant parts, it is considered to be poisonous that is deadly to herbivorous animals. Unfortunately, defining poisonous plants is difficult because certain poisonous plants are also regarded as good for the treatment of specific conditions (Sadia et al., 2022).
Plant poisoning in animals is usually unintentional, and it most commonly happens under unfavourable situations such as overstocking, grazing trampling and drought; for example, animals could eat hay that has been infected with deadly weeds. It could be unintentional or intentional in people. Poisoning in humans can occur as a result of mixing poisonous and edible plants, contamination of food with poisonous plants or employing plants as cures. To avoid poisonous plants, it is obligatory to identify them first. In this study, foliar anatomical features are used as an aid to identify poisonous species (Botha and Penrith, 2008).
Similar to medical plants, these species can be further classified depending on the presence of specific compounds in various parts of the plant body, that is, alkaloids, glycosides, tannins, phenols and volatile oils. Some medicinal herbs, on the other hand, have deadly effects on humans when taken in large quantities (Baloch et al., 2017). Many poisonous plants have several functions, and in the right amounts or forms, they can be beneficial. Drugs are also derived from these species, for example, digitalis and morphine. Digitalis is a commonly prescribed cardiac drug that, when administered incorrectly, can be deadly toxic. Important medications such as codeine and morphine are derived from the milky juice of the opium plant. These medicines are intended to treat pain, but when used indiscriminately, they can be harmful and even fatal (Fuller and Mcclintock, 1986). On rare occasions, a hazardous chemical is concentrated in a specific area of the plant. Rhubarb’s leaf blade is poisonous, but its petiole is edible. Toxic chemicals are abundant in the fruits and seeds of several plants. When the seeds of castor beans, Ricinus communis, are eaten, a very poisonous chemical lectin called toxalbumin is released. Ingesting more than two or three castor bean seeds can result in death. Furthermore, while many plants are used to adorn our surroundings, certain ornamental plants contain hazardous chemicals (Fuller and Mcclintock, 1986).
Many research work has been carried out on the different aspects of the leaf anatomy, but yet no record on the identification of poisonous plants based on their trichomes exists in Pakistan. The importance of anatomical approaches in taxonomic research cannot be overstated. Without microscopic aspects of the epidermal anatomy, taxonomic monographs are incomplete (Abbas et al., 2022; Majeed et al., 2023a). The size and anticlinal wall, the form of stomata, guard cell profile, subsidiary cells and trichome varieties are some of the foliar epidermal traits of high value (Ashfaq et al., 2019). As a result, taxonomists are interested in learning more about the anatomy of the leaf epidermis. The variances in epidermal traits between species may be attributable to genetic differences or the diversity of natural habitats (Hameed et al., 2020). The relevance of micromorphology in the plant nomenclature has long been recognised since variations within a family, genus or species are frequently revealed in anatomical traits (Shahzad et al., 2022; Majeed et al., 2023b).
The taxonomic study using microscopic techniques is used as a tool for micromorphology of foliar epidermal study using LM and SEM. Transmission light is commonly utilised as a light source in light microscopy (Yuan et al., 2020). In past flower inflorescence studies, fruits and leaf external morphologies were used in plant taxonomy, but currently, the leaf anatomy is used for identification purposes. A great number of studies have been undertaken in Pakistan to analyse the leaf epidermis to observe the leaf micromorphology, but no record has been determined yet for the anatomical study of poisonous plants.
The major goals of the current study are to establish the feasibility of utilising foliar anatomical traits to identify poisonous plant species. Prompt identification plays a crucial role in facilitating effective medical interventions, helping to prevent unintentional consumption or contact. By accurately and consistently identifying poisonous plants, authorities and medical practitioners can enhance public safety and protect the public from potential hazards.
During the current study, 25 poisonous plant species were collected from various locations in the lower Himalayas between March and September 2021. The collected species were dried, pressed, mounted and labelled. Plant species were identified using herbarium specimens from the Herbarium of Pakistan (ISL) QAU, Islamabad, as well as information from the flora of Pakistan (http://www.eflora.org). The Plant List (TPL) (http://www.theplantlist.org) and the International Plant Names Index (http://www.ipni.org) were used to confirm the plant species. Table 1 lists the names of plant species, voucher number, collector, location and altitude.
Collector names, voucher numbers, altitude, locality and district of studied species.
| S. No. | Taxa | Collector | Voucher number | Altitude (m) | Locality | District |
|---|---|---|---|---|---|---|
| 1 | Agave americana L. | Aqsa Abid | 131601 | 540 | QAU | Islamabad |
| 2 | Alocasia macrorrhizos (L.) G.Don | Aqsa Abid | 131602 | 508 | Rawalpindi | Punjab |
| 3 | Argemone mexicana L. | Aqsa Abid | 131603 | 540 | QAU | Islamabad |
| 4 | Brugmansia versicolor Lagerh | Sabir Ahmed | 131604 | 540 | Capital territory | Islamabad |
| 5 | Butea monosperma (Lam.) Taub. | Aqsa Abid, Salman | 131605 | 540 | QAU colony | Islamabad |
| 6 | Buxus pilosula Urb | Aqsa Abid | 131606 | 1064 | Margalla hills | Islamabad |
| 7 | Chenopodium ambrosioides L. | Aqsa Abid | 131607 | 508 | Rawalpindi | Punjab |
| 8 | Chrozophora tinctoria (L.) A.Juss. | Aqsa Abid | 131608 | 980 | Islamia college Peshawar | KPK |
| 9 | Datura innoxia Mill. | Aqsa Abid | 131609 | 508 | Rawalpindi | Punjab |
| 10 | Duranta erecta L. | Aqsa Abid | 131610 | 540 | Capital territory | Islamabad |
| 11 | Euphorbia helioscopia L. | Aqsa Abid | 131611 | 508 | Dhamial camp | Punjab |
| 12 | Euphorbia pulcherrima Willd. ex Klotzsch | Aqsa Abid | 131612 | 540 | QAU girls hostel | Islamabad |
| 13 | Euphorbia royleana Boiss | Aqsa Abid | 131613 | 540 | QAU | Islamabad |
| 14 | Ipomoea carnea Jacq. | Aqsa Abid | 131614 | 279 | Chakri | Rawalpimdi |
| 15 | Parthenium hysterophorus L. | Aqsa Abid | 131615 | 482 | Dhamial camp | Rawalpindi |
| 16 | Peganum harmala L. | Aqsa Abid | 131616 | 508 | Rawalpindi | Punjab |
| 17 | Physalis angulata L. | Aqsa Abid | 131617 | 540 | QAU | Islamabad |
| 18 | Ranunculus sceleratus L. | Beenish | 131618 | 165 | Dera ismail khan | Punjab |
| 19 | Ricinus communis L. | Aqsa Abid | 131619 | 482 | Dhamial camp | Islamabad |
| 20 | Sambucus nigra L. | Aqsa Abid | 131620 | 540 | QAU | Islamabad |
| 21 | Solanum nigrum L. | Aqsa Abid | 131621 | 1604 | Margalla hills | Islamabad |
| 22 | Solanum incanum L. | Aqsa Abid | 131622 | 279 | Chakri | Rawalpindi |
| 23 | Sorghum halepense (L.) Pers. | Aqsa Abid | 131623 | 500 | Morgah | Rawalpindi |
| 24 | Thevetia peruviana (Pers.) K.Schum. | Aqsa Abid | 131624 | 540 | Capital territory | Islamabad |
| 25 | Trifolium repens L. | Bushra Ali | 131625 | 2601 | Khaplu | Gilgit Baltistan |
Using a light microscope, fresh leaf samples of 25 poisonous plants were investigated in which trichomes were examined in nine species following the method described by Raza et al. (2020). To keep the leaves from drying out, they were picked from actively developing plants and dipped in water for some time. Then, 1 or 2 leaves were placed in a test tube and dipped in 70% lactic acid and 30% nitric acid for 2 min or until the leaves became translucent. The leaves were then transferred into a cell culture dish, and the translucent sections were rinsed 2–3 times with water. Through a camel hair brush and sharp needle, the epidermal portions from the abaxial and adaxial sides of the sample were meticulously detached. The isolated epidermis was processed with a droplet of lactic acid to clean the section before being placed on a slide by coverslips. To make permanent slides, the margins of coverslips on slides were covered with translucent nail polish. For each plant species, six or seven samples of the abaxial and adaxial surfaces were prepared. A Nikon Microscope with Plan-40X/0.65 lens was used to examine the set slides. Using an XSP-45LCD microscope, the characteristics of the leaf epidermis were photographed. The following characteristics were observed under microscopy: width and length of epidermal cells, stomatal apparatus, trichomes and morphology of the epidermal cell, stomatal complex, the pattern of anticlinal walls (AW), and types of trichomes. Table 2 and Table 3 summarise the qualitative and quantitative characteristics, respectively. Mean (minimum–maximum) ± standard error SE (e.g., 56.7–160 = 89.6 ± 9.5) are used to express quantitative properties. For each abaxial and adaxial surface, five readings of each characteristic were recorded. The quantitative data were analysed using SPSS software IBM, Chicago, USA to calculate the values of mean, maximum, minimum and standard error. These data are extremely useful in identifying species and various epidermal features. These indices include information of length and width of the epidermal cell, subsidiary cells, stomatal complex and trichomes.
Comprehensive review study of poisonous plants.
| Sr. No. | Plant species | Family | Flowering period | Common name | Habit | Status | Global distribution | Poisonous part | Poisonous compounds | Side effects | Citation |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 1. | Agave americana | Asparagaceae | Spring, summer, fall winter | Century plant, maguey, or American aloe | Rosette-forming herbaceous perennial succulent | Cultivated | Mexico, United States | Leaves sap/juice | Acrid volatile oil, oxalic acid, sapono-side | Redness and swelling, swelling of small blood vessels (veins), skin sores | Ahmad (2012) |
| 2. | Alocasia macrorrhiza | Aricaceae | Spring, summer, fall winter | Taro/ elephants ear | Evergreen perennial | Cultivated | Africa, western Asia, eastern Asia, the Pacific Islands, America, the USA, Brazil | Leaves and corms | Calcium oxalate and oxalic acid | Conjunctivitis, pruritus, blindness | Ufelle et al. (2018) |
| 3. | Argemone mexicana | Papaveraceae | March, April, May, June | Mexican prickly poppy, flowering thistle | Broadleaved herbaceous, seed propagated | Wild | Central Mexico, Honduras | All parts of plants are poisonous | Sanguinarine, dihydrosanguinarine | Perianal itching, pneumonia myocarditis and congestive cardiac failure, ascites, sarcoid-like skin changes, alopecia, hepatomegaly | Brahmachari et al. (2013) |
| 4. | Brugmansia versicolor | Solanaceae | Mid-summer to fall | Angel’s trumpets | Broadleaf evergreen | Cultivated | Western part of South America, south of the Gulf of Guayaquil in Ecuador | Flowers, leaves, and seeds | Alkaloids like atropine, scopolamine and hyoscyamine | Intense thirst, dilated pupils, high or low blood pressure, fast heartbeat, convulsions, difficulty breathing, illusions, paralysis, coma, death, nervousness, loss of memory | Petricevich et al. (2020) |
| 5. | Butea monosperma | Fabaceae | January to March | Flame-of-the-forest | An erect deciduous tree with young parts hairy | Wild | Sub-tropical and tropical areas of the Indian Subcontinent and Asian southeast region. | All parts especially seeds | Fixed oil in the seed and glucoside butrin of the flower sap | Dizziness, headache, hypotension | Ahmad (2012) |
| 6. | Chenopodium ambrosioides | Amaranthaceae | April -January | Mexican tea, Jesuit’s tea | Polymorphic annual, and perennial herb | Wild | Native to Central America, South America, and southern Mexico | Leaves | Carvacrol, caryophyllene oxide and ascaridole | Vomiting, dizziness, headache, temporary deafness, kidney and liver damage, convulsions, paralysis, death | Da Silva et al. (2014) |
| 7. | Chrozophora tinctoria | Euphorbiaceae | April to June | Dyer’s croton, giradol, or turnsole | Erect densely woolly herb | Wild | Mediterranean, Middle East, India, Pakistan, and Central Asia | All parts of plant are poisonous | Rutin, chrozophorin, saponins | Upset stomach, vomiting, nausea, diarrhoea | Al-Snafi (2015) |
| 8. | Datura inoxia | Solanaceae | July to frost | Pricklyburr | Shrubby, sprawling, short-lived, tender perennial | Wild | Central America, Texas, Colombia | All portions of the plant are toxic especially foliage and seeds | Alkaloids, hyoscyamine, hyoscine | Enlarged pupils, dry mouth, trouble breathing, blurred vision, hallucinations, panic, death | Ahmad (2012) |
| 9. | Datura stramonium | Solanaceae | March through November | Jimsonweed, locoweed, thorn apple, devil’s trumpet | Wild-growing herb | Wild | Central America, Caribbean | Seeds and leaves | Alkaloids, hyoscyamine, hyoscine | Blurred vision, dry mouth, dilated pupils, confusion, combative behaviour hallucinations, difficulty urinating | Ahmad (2012) |
| 10. | Duranta erecta | Verbenaceae | Spring | Pigeon berry | Erect and spreading | Cultivated | Florida, South America | Leaves, fruit and bark are poisonous | Saponin | Vomiting and gastro-intestinal irritation, diarrhoea | Ahmad (2012) |
| 11. | Euphorbia helioscopia | Euphorbiaceae | Mid-spring to late summer, May to October | Wart spurge, umbrella milkweed and madwoman’s milk | Erect perennial herb | Wild | Europe, northern Africa, Asia | Leaves | Diterpene 12-deoxypharbol | Nausea, allergic reactions, skin irritation, vomiting | Ahmad (2012) |
| 12. | Euphorbia heterophylla | Euphorbiaceae | September-March | Mexican fireplant, painted euphorbia, wild poinsettia | A small, annual herb, glabrous | Wild | Central & S. USA, America, tropical Africa, Asia, Pacific countries | All fragments of the plant are lethal | Oil, saponins, glycosides | Nausea, allergic reactions, skin irritation, vomiting | Adedapo et al. (2004) |
| 13. | Euphorbia pulcherrima | Euphorbiaceae | October to December | Poinsettia | Shrub or small tree | Wild | Mexico, Central America to southern Guatemala | All parts of plant are poisonous | Water soluble caoutchouc | Upset stomach, vomiting, nausea, diarrhoea | Ahmad (2012) |
| 14. | Euphorbia royleana | Euphorbiaceae | Spring to early summer (March–July) | Sullu spurge, and Royle’s spurge | Deciduous, cactus-like, succulent shrub or small tree | Wild | Himalaya mountains from Pakistan, Nepal to western China India, Bhutan, Myanmar | All parts are poisonous | Epitaraxerol, ellagic acid, euphol, taraxerol, sitosterol in milky latex | Nausea, vomiting | Bhatia et al. (2014) |
| 15. | Ipomoea carnea | Convolvulaceae | Fall–summer | Pink morning glory, bush morning glory | Twining plant | Wild | Tropical America, Caribbean, America, Africa, Australia, and Asia | Seeds and leaves | N-methyl-trans-4-hydroxy-l-proline, calystegines B1, swainsonine, 2-epilentiginosine and B2, B3 and C1 | Abnormal endocrine functions and gastrointestinal functions, immune system alternation, abnormality in embryogenesis | Wanule and Balkhande (2012) |
| 16. | Nerium oleander | Apocynaceae | July to October | Oleander or nerium | Erect shrub bearing pink or white flowers | Cultivated | Mediterranean Basin | Entire plant | Cardiac glycosides of the cardenolide type | Weakness, diarrhoea, nausea, vomiting, headache, pain in stomach, death | Ahmad (2012) |
| 17. | Parthenium hysterophorus | Asteraceae | March to October | Santa Maria feverfew, whitetop weed | Erect stout undershrubs | Wild | Subtropics of North and South America | All its parts including trichomes and pollen | Parthenin and other phenolic acids | Eczema skin inflammation, hay fever, asthma, burning and blisters, breathlessness and choking, allergic rhinitis, black spots, diarrhoea, severe erythematous eruptions | Ahmad (2012) |
| 18. | Peganum harmala | Nitrariaceae | April and October | Wild rue, Syrian rue, African rue, esfand or espand, or harmel | Perennial, herbaceous plant | Wild | Middle East, Africa, Mediterranean area, Indian Pakistan, Iran, Africa, Central Asian republics semi-arid regions | Leaves and seeds | β-carbolines such as: harmalol, harman harmaline, harmine, and quinazoline derivatives | Hallucinations, neurosensory syndromes, bradycardia, nausea, vomiting | Mahmoudian et al. (2002) |
| 19. | Physalis angulate | Solanaceae | Spring/ summer/ autumn | Cut-leaf ground-cherry, angular winter cherry | Multi-stemmed and spreading | Wild | USA, South America, NC | Unripe berries and leaves | Physalins | Headache, discomfort in stomach, dropped temperature, expanded pupils, nausea, diarrhoea, cardiac and breathing depression, loss of consciousness, fatal schistosomiasis | Pomilio et al. (2008) |
| 20. | Ranunculus sceleratus | Ranunculaceae | May to September | Celery-leaved buttercup | Annual or short-lived perennial | Wild | Europe, Britain, primarily in central and northern areas | All parts of the plant are poisonous | Glycoside ranunculin | Enormously annoying to skin and mucous membranes. It may cause pain and burning perceptions, tongue inflammation, and intensification in saliva | Ahmad (2012) |
| 21. | Ricinus communis | Euphorbiaceae | June to October | Castor oil plant | Tender perennial large shrub or small tree | Wild | Southeastern Basin, India Mediterranean, Eastern Africa | Seeds and leaves | Toxalbumin ricin | Nausea, sickness, diarrhoea, abdominal pain, desiccation, shock, simple fluid and chemical disturbances, destruction to the liver, kidney and pancreas, and eventually death | Ahmad (2012) |
| 22. | Solanum incanum | Solanaceae | October–January | Thorn apple, bitter apple, bitterball and bitter tomato | An erect prickly shrub, stem prickly and prickles straight sharp | Wild | Saharan desert in Africa, Middle East, India | Dried unripe fruits | Glycoalkaloids such as solasonine, alkylamines such as nitrosamines and carcinogenic glycosides | Stomach pain, vomiting, diarrhoea | Madzimure et al. (2013) |
| 23. | Solanum nigrum | Solanaceae | July to September | Black nightshade or blackberry nightshade | Short-lived perennial shrub | Wild | South America | Fruits, leaves | Steroidal glycoalkaloids like alpha-solanine and alpha-chaconine | Stomach pain, vomiting, diarrhoea | Jabamalairaj et al. (2019) |
| 24. | Sorghum halepense | Poaceae | Fall to summer | Johnsongrass | Arching dense erect spreading | Wild | Eastern, Mediteranean, Middle East countries | Leaves | Dhurrin, a cyanogenic glycoside, toxic levels of nitrates | Nervousness, progressive feebleness and difficulty breathing, breathlessness, increased pulse rate, muscular jerking, convulsions, death | Khan et al. (2018) |
| 25. | Thevetia peruviana | Apocynaceae | Summer to fall | Luckynut, yellow oleander | Perennial or evergreen tropical shrub | Cultivated | Mexico, tropical South America | All parts of the plant are poisonous, especially the kernels of the fruits and leaves | Glycosides, thevetin, cerebrin, neriifolin | Sickness, dizziness, electrolyte turbulences, cardiac dysrhythmias | Ahmad (2012) |
| 26. | Trifolium repens | Fabaceae | Spring – summer | White clover | Creeping, prostrate | Wild | Europe, British Isles, central Asia | Leaves | Eyanogenic glucosides linamarin and lotaustralin | Outbreaks, muscle ache, pain, sickness, and vaginal flow (spotting) | Refsgaard et al. (2010) |
| 27. | Xanthium strumarium | Asteraceae | Fall to summer | Clotbur, common cocklebur, woolgarie bur | Erect, ground cover herb | Wild | North America | Leaves and seeds | Carboxyatractyloside | Sickness, muscular tremors, liver disintegration and seldom death | Ahmad (2012) |
NC, North Canada.
Qualitative foliar anatomical features of poisonous plants.
| Plant species | Ad × Ab | ECS | AW | Stomata (P/A) | ST | GCS | Glands P/A | SPS | Trichome | |
|---|---|---|---|---|---|---|---|---|---|---|
| Glandular | Non-glandular | |||||||||
| Chrozophora tinctoria | Ad | Irregular | Deeply sinous | P | Anisocytic | Broad bean-shaped | A | Narrow elliptical | - | Sessile stellate |
| Ab | Irregular | Deeply sinous | P | Anisocytic | Broad bean-shaped | A | Narrow elliptical | - | Sessile stellate | |
| Buxus pilosula | Ad | Polygonal | Straight | A | - | A | Very narrowly elliptical | - | - | |
| Ab | Polygonal | Straight | P | Paracytic | Broad bean-shaped | A | Very narrowly elliptical | - | - | |
| Parthenium hysterophorus | Ad | Irregular | Sinuate | P | Anomocytic | Broad bean-shaped | P | Elliptical | - | |
| Ab | Irregular | Sinuate | P | Anomocytic | Broad bean-shaped | P | Elliptical | - | Segmented with pointed tip and broad base | |
| Datura innoxia | Ad | Irregular | Deeply undulate | P | Anisocytic anomocytic | Broad bean-shaped | A | Widely elliptical | - | Multicellular with pointed tip and broad base |
| Ab | Polygonal | Straight | P | Anomocytic | Broad bean-shaped | A | Widely elliptical | - | Multicellular with pointed tip and broad base | |
| Ricinus communis | Ad | Polygonal | Straight/angular | P | Paracytic | Broad bean-shaped | Elliptical | - | - | |
| Ab | Polygonal | Straight | P | Paracytic | Broad bean-shaped | A | Elliptical | - | - | |
| Alocasia macrorrhizos | Ad | Polygonal | Straight | A | A | - | - | |||
| Ab | Polygonal | Straight | P | Paracytic | Broad bean-shaped | A | Broad elliptical | - | - | |
| Euphorbia royleana | Ad | Polygonal | Straight | A | - | - | A | - | - | - |
| Ab | Polygonal | Straight | P | Paracytic | Broad bean-shaped | A | Very broad elliptical | - | - | |
| Ranunculus sceleratus | Ad | Irregular | Wavy to sinous | P | Anomocytic | Bean-shaped | A | Elliptical | - | - |
| Ab | Irregular | Wavy to sinous | P | Anomocytic | Bean-shaped | A | Elliptical | - | - | |
| Thevetia peruviana | Ad | Irregular | Undulate | A | - | Broad bean-shaped | A | Widely elliptical | - | - |
| Ab | Polygonal | Straight/wavy | P | Anisocytic | Broad bean-shaped | A | Widely elliptical | - | - | |
| Agave americana | Ad | Polygonal | Straight | P | Paracytic | Narrow bean-shaped | A | Concave-shaped | - | - |
| Ab | Polygonal | Straight | P | Paracytic | Narrow bean-shaped | A | Concave-shaped | - | - | |
| Brugmansia versicolor | Ad | Polygonal | Straight/angular | P | Anisocytic | Broad bean-shaped | A | Elliptical | - | Multicellular with pointed tip and broad base unicellular with bulbous tip |
| Ab | Irregular | Undulate/sinous | P | Anomocytic | Broad bean-shaped | A | Widely elliptical | - | Multicellular with pointed tip and broad base unicellular with bulbous tip | |
| Sorghum halepense | Ad | Rectangular | Thick sinous walls | p | Paracytic | Dumb bell-shaped | A | Very narrow elliptical | - | - |
| Ab | Rectangular | Thick sinous walls | P | Paracytic | Dumb bell-shaped | A | Very narrow elliptical | - | - | |
| Duranta repens | Ad | Polygonal | Straight | A | - | - | P | - | - | - |
| Ab | Polygonal | Straight | P | Anisocytic | Broad bean-shaped | P | Widely elliptical | Unicellular with pointed tip | ||
| Physalis angulata | Ad | Irregular | Deeply sinous | P | Anomocytic | Broad bean-shaped | A | Narrow elliptical | - | - |
| Ab | Irregular | Deeply sinous | P | Anomocytic | Broad bean-shaped | A | Narrow elliptical | - | - | |
| Chenopodium ambrosioides | Ad | Polygonal | Angular | P | Anomocytic | Narrow kidney-shaped | P | Wide elliptical | Multicellular capitate | - |
| Ab | Irregular | Wavy | P | Anisocytic | Wide kidney-shaped | P | Elliptical | Multicellular capitate | - | |
| Trifolium repens | Ad | Irregular | Sinous | P | Anomocytic | Broad bean-shaped | A | Elliptical | - | - |
| Ab | Polygonal | Straight/angular | P | Anisocytic | Broad bean-shaped | A | Narrow elliptical | Multicellular capitate | - | |
| Solanum nigrum | Ad | Polygonal | Straight | P | Anisocytic | Broad bean-shaped | A | Narrow elliptical | - | Multicellular 3–6 celled long with pointed tip |
| Ab | Irregular | Undulate | P | Anomocytic | Broad bean-shaped | A | Elliptical | Multicellular 3–6 celled long with pointed tip | ||
| Butea monosperma | Ad | Polygonal | Angular | A | - | - | A | Elliptical | - | - |
| Ab | Irregular | Wavy | P | Paracytic | Narrow bean-shaped | P | Very narrow elliptical | - | Unicellular with pointed tip | |
| Argemone mexicana | Ad | Polygonal | Angular | P | Anomocytic | Broad bean-shaped | Narrow elliptical | - | - | |
| Ab | Heptagonal | Angular | P | Anomocytic | Broad bean-shaped | A | Very narrow elliptical | - | - | |
| Peganum harmala | Ad | Polygonal | Straight | P | Anomocytic | Broad bean-shaped | A | Wide elliptical | - | - |
| Ab | Polygonal | Straight | P | Anomocytic | Broad bean-shaped | A | Wide elliptical | - | - | |
| Solanum incanum | Ad | Rectangular | Straight | P | Anisocytic | Widely bean-shaped | A | Narrow elliptical | Stellate unicellular with pointed tip | |
| Ab | Polygonal | Angular | P | Anisocytic | Widely bean-shaped | A | Narrow elliptical | Stellate unicellular with pointed tip | ||
| Euphorbia helioscopia | Ad | Polygonal | Straight | A | - | - | A | - | - | - |
| Ab | Polygonal | Straight | P | Anomocytic | Broad bean-shaped | A | Narrow elliptical | - | - | |
| Euphorbia pulcherrima | Ad | Irregular | Undulate | A | A | Multicellular with pointed end | ||||
| Ab | Irregular | Undulate | P | Anomocytic | Broad bean-shaped | A | Narrow elliptical | - | Multicellular with pointed end | |
| Ipomoea carnea | Ad | Rectangular to isodiametric | Straight | P | Cyclocytic | Broad bean-shaped | Very broad elliptical | Subsessile, capitate having 5–6 celled with a flat head | Unicellular and conical-shaped | |
| Ab | Irregular/tetragonal | Straight/sinous | P | Cyclocytic/ paracytic | Broad bean-shaped | A | Very broad elliptical | Sub sessile, capitate having 5–6 celled a with flat head | Unicellular and conical-shaped | |
| Ipomoea carnea | Ad | Polygonal | Straight/angular | A | A | - | ||||
| Ab | Polygonal | Straight | P | Anomocytic | Broad bean-shaped | A | Wide elliptical | Multicellular with bulbous head | ||
Ab, abaxial; Ad, adaxial; AW, anticlinal walls; ECS, epidermal cells shape; GCS, guard cells shape; SPS, stomatal pore shape; ST, stomatal type.
For SEM investigation, dried and mature leaves were washed with ethanol to expel the flotsam and jetsam. For slide preparation, the leaf cuttings were placed on stubs with a twofold covered scotch tape. The samples were super-coated with gold-palladium and examined by SEM (Show JEOL-5910, USA) introduced in the Central Library Office of Material Science College of Peshawar. A Polaroid P/N 665 film was used to take pictures. The samples were analysed beneath the magnifying lens and scrutinised the different micromorphological highlights (epidermal cells, trichomes, stomata) of the leaf (Gul et al., 2019).
The present investigation begins by offering a well-structured overview through a critical examination of the literature on poisonous plants from different regions of Islamabad, as discussed in Table 2. According to this review study, the most dominant families were Solanaceae (five species) and Euphorbiaceae (five species).
The present study examined the qualitative and quantitative features of 25 poisonous plant species from various families in Islamabad. The qualitative attributes examined included the appearance of epidermal cells, the pattern of AW, types of stomata and trichome types on both abaxial and adaxial surfaces. Quantitative attributes, such as the size of epidermal cells, stomatal complexes and trichomes, were also measured and shown in a tabular form (Table 3 and Table 4). The light microphotographs of the considered taxa are demonstrated in Figures 1–6, and the scanning micrographs of trichomes of the studied species are demonstrated in Figures 7–9. The dominant families in the current study were Solanaceae (five species), including Brugmansia versicolor, Datura innoxia, Physalis angulata, Solanum nigrum, Solanum incanum and Euphorbiaceae, which comprises Chrozophora tinctoria, R. communis, Euphorbia royleana, Euphorbia pulcherrima and Euphorbia helioscopia, followed by Fabaceae having two species (Trifolium repens and Butea monosperma). While rest of the families contains one species each, including Ranunculaceae (Ranunculus sceleratus), Apocynaceae (Thevetia peruviana), Buxaceae (Buxus pilosula), Araceae (Alocasia macrorrhiza), Asparagaceae (Agave Americana), Poaceae (Sorghum halepense), Verbenaceae (Duranta erecta), Amaranthaceae (Chenopodium ambrosioides), Papaveraceae (Argemone mexicana), Convolvulaceae (Ipomoea carnea), Nitrariaceae (Peganum harmala) and Adoxaceae (Sambucus nigra). This study aimed to provide valuable information for the identification of poisonous plants based on their micromorphological features using microscopic techniques.
Figure 1.
LM shapes of epidermal cells, patterns of AW, stomata and trichomes of poisonous plants. Scale bar = 5 μm. (A) Agave americana, (B) adaxial surface, (C) abaxial surface, (D) Argemone mexicana, (E) adaxial surface, (F) abaxial surface, (G) Brugmansia versicolor, (H) adaxial surface, (I) abaxial surface, (J) Butea monosperma, (K) adaxial surface (L) abaxial surface. AW, anticlinal walls; LMs, light micrographs.
Figure 2.
LM shapes of epidermal cells, patterns of AW, stomata and trichomes of poisonous plants. Scale bar = 5 μm. (A) Buxus pilosula, (B) adaxial surface, (C) abaxial surface, (D) Chenopodium ambrosioides, (E) adaxial surface, (F) abaxial surface, (G) Chrozophora tinctoria, (H) adaxial surface, (I) abaxial surface, (J) Alocasia macrorrhizos, (K) adaxial surface, (L) abaxial surface. AW, anticlinal walls; LMs, light micrographs.
Figure 3.
LM shapes of epidermal cells, patterns of AW, stomata and trichomes of poisonous plants. Scale bar = 5 μm. (A) Datura innoxia, (B) adaxial surface, (C) abaxial surface, (D) Duranta repens, (E) adaxial surface, (F) abaxial surface, (G) Euphorbia helioscopia, (H) adaxial surface, (I) abaxial surface, (J) Euphorbia pulcherrima, (K) adaxial surface, (L) abaxial surface. AW, anticlinal walls; LMs, light micrographs.
Figure 4.
LM shapes of epidermal cells, patterns of AW, stomata and trichomes of poisonous plants. Scale bar = 5 μm. (A) Euphorbia royleana, (B) adaxial surface, (C) abaxial surface, (D) Ipomoea carnea, (E) adaxial surface, (F) abaxial surface, (G) Parthenium hysterophorus, (H) adaxial surface, (I) abaxial surface, (J) Peganum harmala, (K) adaxial surface, (L) abaxial surface. AW, anticlinal walls; LMs, light micrographs.
Figure 5.
LM shapes of epidermal cells, patterns of AW, stomata and trichomes of poisonous plants. Scale bar = 5 μm. (A) Physalis angulate, (B) adaxial surface, (C) abaxial surface, (D) Ranunculus sceleratus, (E) adaxial surface, (F) abaxial surface, (G) Ricinus communis, (H) adaxial surface, (I) abaxial surface, (J) Sambucus nigra, (K) adaxial surface, (L) Abaxial surface. AW, anticlinal walls; LMs, light micrographs.
Figure 6.
LM shapes of epidermal cells, patterns of AW, stomata and trichomes of poisonous plants. Scale bar = 5 μm. (A) Solanum nigrum, (B) adaxial surface, (C) abaxial surface, (D) Solanum incanum, (E) adaxial surface, (F) abaxial surface, (G) Sorghum halepense, (H) adaxial surface, (I) abaxial surface, (J) Thevetia peruviana, (K) adaxial surface, (L) abaxial surface, (M) Trifolium repens, (N) adaxial surface, (O) abaxial surface. AW, anticlinal walls; LMs, light micrographs.
Figure 7.
Scanning micrographs (SEM); Brugmansia versicolor (A-C), Butea monosperma (D-F), Chrozophora tinctoria (G-I), Buxus pilosula (J-L).
Figure 8.
Scanning micrographs (SEM); Datura innoxia (A-C), Duranta rapens (D-F), Euphorbia pulcherrima (G-I), Euphorbia royleana (J-L).
Figure 9.
Scanning micrographs (SEM); Ipomoea carnea (A-C), Parthenium hysterophorus (D-F), Sambucus nigraum (G-I).
Quantitative attributes of studied species.
| Plant name | Ad × Ab | Length of epidermal cell | Width of epidermal cell | Length of guard cells | Width of guard cells | Length of stomata Mean | Width of stomata | Length of subsidiary cell | Width of subsidiary cell | Length of stomatal pore | Width of stomatal pore | Trichome length Mean (Min–Max) ± SE (μm) | Trichome width Mean |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Agave americana | Ad | 69.95 (58.75–81.25)±3.97 | 24.65 (23.75–23.75) ± 0.37 | 20.0 (17.75–22.0) ± 0.78 | 6.90 (6.25–7.75) ±0.29 | 27.45 (25.25–29.75) ± 0.81 | 11.35 (10.25–12.75) ± 0.50 | 52.50 (43.75–63.75) ± 3.29 | 16.15 (12.75–21.25)± 1.65 | 17.30 (16.25–18.75) ± 0.45 | 1.55 (1.0–2.25) ± 0.242 | Absent | Absent |
| Ab | 63.35 (53.75–81.25) ± 4.75 | 28.30 (26.25–30.25) ± 0.77 | 21.05 (20.25–21.75) ± 0.25 | 5.85 (4.75–7.25) ±0.43 | 24.30 (18.75–27.75) ± 1.77 | 13.15 (11.25–14.75) ± 0.65 | 50.55 (43.75–54.75) ± 2.14 | 25.35 (24.0–26.50) ± 0.46 | 19.40 (18.0–20.25) ± 0.44 | 0.90 (0.50–1.25) ± 0.16 | Absent | Absent | |
| Argemone mexicana | Ad | 65.75 (50.25–73.25) ± 4.1 | 34.50 (32.25–37.25) ± 0.96 | 32.30 (31.25–34.0) ± 0.51 | 12.55 (10.25–13.75) ±0.64 | 32.95 (31.25–34.75) ± 0.60 | 26.55 (22.75–29.75) ± 1.39 | 54.50 (50.25–57.75) ± 1.23 | 26.45 (22.25–31.25)± 1.50 | 20.95 (18.75–22.75) ± 0.75 | 6.25 (5.25–7.25) ± 0.35 | Absent | Absent |
| Ab | 57.95 (54.75–61.25)± 1.05 | 41.85 (27.25–47.25) ±3.6 | 27.20 (22.75–32.0) ± 1.7 | 12.45 (11.25–14.75) ± 0.64 | 30.55 (27.75–32.75) ±0.98 | 27.05 (23.75–29.75) ± 1.17 | 60.85 (51.75–74.75) ± 4.02 | 37.95 (34.75–41.25) ± 1.27 | 22.05 (20.25–23.75) ± 0.60 | 7.05 (5,25–8.75) ± 0.60 | Absent | Absent | |
| Brugmansia versicolor | Ad | 42.25 (36.25–51.25) ± 2.55 | 36.25 (32.75–41.25)± 1.51 | 32.05 (30.25–33.75) ± 0.60 | 10.45 (8.75—12.25) ± 0.60 | 32.30 (31.25–33.75) ± 0.45 | 28.15 (26.25–29.75) ± 0.62 | 45.55 (38.75–53.25) ± 2.69 | 29.55 (27.75–31.25) ± 0.60 | 19.55 (17.75–21.25) ± 0.60 | 6.85 (3.75–9.75) ± 1.14 | 356.8 (341.25–375.25) ± 6.1 | 46.40 (41.25–52.25) ± 1.93 |
| Ab | 39.30 (36.25–46.50) ± 1.84 | 33.75 (30.25–36.25) ± 1.34 | 27.95 (26.25–29.75) ± 0.60 | 10.90 (9.50–12.25) ± 0.54 | 27.95 (26.25–29.75) ± 0.60 | 25.15 (23.75–26.25) ± 0.43 | 47.40 (45.75–48.75) ± 0.55 | 32.30 (31.25–33.75) ± 0.45 | 19.70 (18.75–20.75) ± 0.37 | 8.10 (6.25–9.50) ± 0.58 | 307.35 (300.75–316.25) ± 2.62 | 25.55 (23.75–27.75) ± 0.68 | |
| Butea monosperma | Ab | 30.95 (26.25–38.75)± 2.11 | 14.65 (11.25–18.25) ± 1.1 | 14.15 (13.25–l5.25) ± 0.36 | 6.75 (5.75–7.75) ± 0.35 | 14.15 (13.25–15.25) ± 0.36 | 10.7 (7.75–13.75) ± 1.14 | 23.40 (22.25–24.50) ± 0.40 | 9.70 (8.75–10.50) ± 0.32 | 8.95 (7.75–10.25) ± 0.40 | 4.35 (3.75–5.25) ± 0.29 | 168.3 (148.75–183.75) ± 6.07 | 11.25 (8.75–13.75) ± 0.92 |
| Ad | 30.75 (28.75–33.75) ± 0.85 | 21.10 (18.75–23.75) ± 0.96 | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent | 225.9 (212.75–234.0) ± 3.8 | 15.35 (13.75–17.25) ± 0.57 | |
| Buxus pilosula | Ad | 55.45 (52.75–57.75) ± 0.96 | 40.0 (37.75–42.0) ± 0.78 | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent |
| Ab | 45.15 (37.75–56.25) ± 3.79 | 29.65 (26.25–32.75) ± 1.07 | 25.25 (23.75–27.75) ± 0.77 | 4.30 (3.0–5.25) ± 0.40 | 25.25 (23.75–27.75) ± 0.77 | 12.85 (11.25–14.25) ± 0.53 | 39.70 (35.75–46.25) ± 1.91 | 9.95 (8.75–11.25) ± 0.40 | 21.65 (20.25–23.25) ± 0.57 | 3.95 (2.75–5.25) ± 0.46 | Absent | Absent | |
| Chenopodium ambrosioides | Ad | 50.70 (48.0–53.25) ± 1.00 | 26.55 (24.75–28.75) ± 0.75 | 24.15 (22.75–25.75) ± 0.50 | 9.35 (8.50–10.25) ± 0.30 | 24.25 (22.75–25.25) ± 0.44 | 19.45 (17.75–20.75) ± 0.53 | 28.75 (25.25–32.25) ± 1.36 | 26.35 (23.75–30.25) ± 1.16 | 15.85 (14.75–17.25) ± 0.43 | 7.35 (6.25–8.75) ± 0.43 | 66.05 (63.75–67.75) ± 0.76 | 20.85 (17.75–23.75) ± 1.06 |
| Ab | 75.05 (72.75–77.25) ± 0.81 | 28.05 (26.25–30.25) ± 0.68 | 20.45 (18.75–22.25) ± 0.60 | 8.55 (7.25–9.75) ± 0.46 | 21.25 (19.75–22.75) ± 0.57 | 18.95 (17.75–22.75) ± 0.57 | 44.75 (42.75–47.25) ± 0.75 | 18.45 (16.25–22.0) ± 1.01 | 14.30 (12.0–15.75) ± 0.66 | 8.05 (6.25–10.25) ± 0.68 | 57.70 (52.25–64.0) ± 2.28 | 26.25 (24.75–27.75) ± 0.57 | |
| Chrozophora tinctoria | Ad | 45.25 (38.75–57.25) ± 3.21 | 23.0 (21.225–24.75) ± 0.60 | 32.05 (30.25–33.75) ± 0.60 | 9.85 (8.75–11.25) ± 0.43 | 32.25 (30.25–33.75) ± 0.68 | 20.4(18.75–22.0) ± 0.56 | 44.0 (37.75–52.25) ± 2.51 | 15.45 (13.75–17.25) ± 0.60 | 17.0 (15.25–18.75) ± 0.60 | 4.8 (3.75–5.75) ± 0.33 | 226.2(214.0–248.7) ± 6.01 | 10.45 (7.25–12.75) ± 1.05 |
| Ab | 48.4(43.75–56.25) ± 2.10 | 18.25 (13.75–23.75) ± 1.7 | 33.25 (31.25–35.25) ± 0.75 | 7.55 (6.25–8.75) ± 0.40 | 32.95 (30.25–35.25) ± 0.94 | 20.55 (18.75–22.25) ± 0.60 | 41.0(35.25–48.75) ± 2.72 | 19.35 (17.75–21.25) ± 0.62 | 15.49 (13.75–17.25) ± 0.58 | 3.80 (3.0–4.75) ± 0.36 | 182.4 (143.75–218.75) ± 16.0 | 9.95 (8.75–11.25) ± 0.40 | |
| Alocasia macrorrhizos | Ad | 57.05 (50.25–65.25) ± 2.83 | 26.95 (25.25–28.25) ± 0.53 | 34.60 (32.75–36.50) ± 0.64 | 12.15 (10.75–13.75) ± 0.53 | 34.30 (32.75–36.50) ± 0.69 | 26.60 (24.75–28.75) ± 0.77 | 32.55 (30.75–34.75) ± 0.75 | 10.15 (8.75–11.50) ± 0.51 | 22.55 (21.25–24.25) ± 0.62 | 6.15 (5.25–7.25) ± 0.40 | Absent | Absent |
| Ab | 52.95 (50.25–56.25) ± 1.04 | 37.05 (35.25–38.75) ± 0.60 | 34.55 (32.75–36.25) ± 0.60 | 10.25 (8.75–13.75) ± 0.92 | 35.05 (32.75–37.25) ± 0.81 | 27.15 (25.75–28.75) ± 0.53 | 28.10 (27.75–29.0) ± 0.33 | 20.45 (16.25–24.75) ± 1.49 | 21.65 (20.25–22.75) ± 0.43 | 8.25 (6.25–11.25) ± 0.85 | Absent | Absent | |
| Datura innoxia | Ad | 50.55 (48.75–52.75) ± 0.68 | 22.75 (21.25–24.75) ± 0.68 | 22.45 (20.25–24.75) ± 0.81 | 6.80 (5.25–8.0) ± 0.50 | 23.85 (20.25–26.25) ± 0.99 | 17.55 (15.25–19.75) ± 0.81 | 38.35 (28.75–44.75) ± 2.90 | 14.95 (12.25–17.75) ± 0.95 | 12.95 (12.25–13.75) ± 0.25 | 6.65 (5.25–7.75) ± 0.43 | 211.8 (191.25–248.75) ± 10.3 | 16.05 (13.75–18.75) ± 0.93 |
| Ab | 48.05 (45.25–50.25) ± 0.98 | 20.55 (18.75–22.75) ± 0.68 | 24.10 (22.75–25.25) ± 0.43 | 6.90 (6.25–7.75) ± 0.26 | 23.95 (22.75–25.25) ± 0.46 | 18.35 (17.25–19.75) ± 0.43 | 29.55 (28.75–30.25) ± 0.25 | 24.50 (22.25–26.25) ± 0.67 | 14.85 (13.75–15.75) ± 0.33 | 5.60 (4.75–6.25) ± 0.29 | 235.0 (228.75–243.75) ± 2.7 | 22.55 (20.25–25.25) ± 0.88 | |
| Duranta repens | Ab | 47.0 (44.50–48.75) ± 0.75 | 19.70 (18.75–20.75) ± 0.34 | 28.15 (27.25–28.75) ± 0.29 | 8.15 (7.25–8.75) ± 0.29 | 29.15 (27.75–31.25) ± 0.62 | 22.35 (21.25–23.75) ± 0.43 | 29.45 (28.0–30.50) ± 0.47 | 22.35 (21.25–23.75) ± 0.43 | 15.05 (14.25–16.25) ± 0.33 | 9.85 (8.75–11.25) ± 0.43 | 150.9 (143.75–158.75) ± 2.53 | 17.05 (14.75–18.75) ± 0.71 |
| Ad | 32.65 (24.75–40.25) ± 3.17 | 14.35 (13.75–15.25) ± 0.29 | 23.35 (21.25–24.75) ± 0.69 | 6.60 (5.25–7.75) ± 0.43 | 23.35 (21.25–24.75) ± 0.69 | 17.05 (16.25–17.75) ± 0.25 | 28.75 (26.25–31.25) ± 0.92 | 10.95 (8.75–12.75) ± 0.75 | 12.25 (11.25–12.75) ± 0.27 | 4.40 (3.75–5.25) ± 0.26 | 159.2 (154.0–162.75) ± 1.64 | 16.1 (14.0–18.25) ± 0.71 | |
| Euphorbia helioscopia | Ad | 99.50 (75.5–125.1) ± 9.02 | 36.50 (35.1–37.3) ± 0.61 | 27.5 (25.1–27.50) ± 0.50 | 19.50 (17.50–20.1) ± 0.50 | 16.50 (12.50–17.50) ± 1.0 | 2.75 (2.50–3.1) ± 0.14 | 27.5 (25.1–27.50) ± 0.50 | 7.9 (7.50–8.25) ± 0.36 | 41.1 (25.1–52.1) ± 4.8 | 16.50 (17.50–25.1) ± 1.0 | 895.2 (750.2–1100) ± 70 | 11.85 (10.1–13.1) ± 1.21 |
| Ab | 84.50 (75.1–87.50) ± 2.42 | 36.50 (35.1–40.3) ± 1.0 | 26.1 (25.1–27.50) ± 0.61 | 20.25 (18.75–22.50) ± 0.61 | 17.50 (15.1–20.3) ± 0.79 | 2.65 (2.50–3.1) ± 0.11 | 26.50 (25.1–27.50) ± 0.61 | 9.50 (7.50–10.1) ± 0.50 | 39.1 (35.1–50.1) ± 2.80 | 18.50 (17.50–20.1) ± 0.61 | Absent | Absent | |
| Euphorbia pulcherrima | Ad | 35.30 (33.75–37.25) ± 0.66 | 20.05 (18.25–21.75) ± 0.68 | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent | 249.9 (238.2–262.7) ± 4.1 | 19.55 (17.75–21.25) ± 0.60 |
| Ab | 34.55 (32.75–36.25) ± 0.60 | 19.55 (17.75–21.25) ± 0.60 | 23.95 (22.75–25.25) ± 0.46 | 8.05 (7.25–9.25) ± 0.40 | 24.55 (22.75–26.25) ± 0.60 | 14.05 (12.75–15.25) ± 0.43 | 33.86 (32.75–34.75) ± 0.33 | 24.55 (22.75–26.25) ± 0.60 | 16.25 (15.25–17.25) ± 0.35 | 3.50 (2.75–4.25) ± 0.27 | 166.5 (160.25–173.25) ± 2.6 | 14.75 (12.75–16.25) ± 0.68 | |
| Euphorbia royleana | Ad | 46.45 (43.75–52.25) ± 1.50 | 37.15 (33.75–39.75) ± 1.04 | 33.45 (30.75–36.25) ± 1.07 | 9.80 (8.75–10.50) ± 0.30 | 33.75 (31.25–36.25) ± 0.92 | 29.85 (27.75–31.25) ± 0.69 | 57.30 (53.75–61.25) ± 1.48 | 31.15 (26.25–39.75) ± 2.29 | 22.30 (20.25–25.25) ± 0.88 | 7.05 (5.25–8.75) ± 0.60 | Absent | Absent |
| Ab | 41.85 (38.75–43.75) ± 0.88 | 30.80 (27.75–34.75) ± 1.23 | 32.05 (30.25–33.75) ± 0.60 | 10.15 (8.75–11.25) ± 0.43 | 31.95 (30.25–33.25) ± 0.53 | 26.45 (25.25–27.75) ± 0.46 | 50.95 (48.75–53.25) ± 0.86 | 24.90 (21.25–29.75) ± 1.40 | 22.95 (21.25–24.75) ± 0.60 | 7.85 (7.0–8.75) ± 0.34 | Absent | Absent | |
| Ipomoea carnea | Ad | 29.25 (26.25–33.75) ± 1.31 | 25.45 (23.75–27.25) ± 0.60 | 24.15 (22.25–27.75) ± 1.01 | 10.45 (9.75–11.25) ± 0.25 | 26.15 (22.75–28.75) ± 1.04 | 21.65 (20.25–22.75) ± 0.43 | 23.45 (7.75–35.25) ± 5.96 | 9.50 (8.75–10.25) ± 0.27 | 19.55 (17.75–21.25) ± 0.60 | 10.05 (7.75–12.25) ± 0.81 | 39.55 (37.75–41.25) ± 0.60 | 12.95 (9.75–17.75) ± 1.43 |
| Ab | 30.95 (26.25–38.75) ± 2.11 | 14.65 (11.25–18.25) ± 1.13 | 14.15 (13.25–15.25) ± 0.36 | 6.75 (5.75–7.75) ± 0.35 | 14.15 (13.25–15.25) ± 0.36 | 10.70 (7.75–13.75) ± 1.14 | 23.40 (22.25–24.50) ± 0.40 | 9.70 (8.75–10.50) ± 0.32 | 8.95 (7.75–10.25) ± 0.40 | 4.35 (3.75–5.25) ± 0.29 | 168.3 (148.75–183.75) ± 6.0 | 11.25 (8.75–13.75) ± 0.92 | |
| Parthenium hysterophorus | Ad | 33.95 (26.25–41.25) ± 2.4 | 15.50 (13.75–18.75) ± 0.92 | 24.15 (23.25–25.25) ± 0.36 | 7.10 (6.25–8.0) ± 0.34 | 24.05 (22.75–25.25) ± 0.43 | 16.4 (15.25–17.75) ± 0.48 | 28.75 (24.50–32.75) ± 1.52 | 18.95 (15.75–23.75) ± 1.45 | 18.1 (16.25–19.75) ± 0.67 | 4.95 (3.75–6.25) ± 0.40 | 165.4 (153.7–173.2) ± 3.70 | 29.74 (28.13–32.64) ± 0.68 |
| Ab | 38.95 (36.50–43.75) ± 1.30 | 18.35 (16.25–21.25) ± 0.84 | 19.95 (18.25–21.25) ± 0.62 | 7.95 (6.25–9.50) ± 0.56 | 20.35 (18.25–22.25) ± 0.78 | 18.10 (16.5–19.75) ± 0.56 | 30.75 (27.75–37.25) ± 1.69 | 18.45 (16.25–20.25) ± 0.75 | 12.0 (7,75–15.25) ± 1.40 | 4.30 (3.75–5.25) ± 0.3 | 195.0 (175.2–211.2) ± 6.19 | 30.85 (29.25–33.75) ± 0.79 | |
| Peganum harmala | Ad | 90.75 (62.75–103.25) ± 7.41 | 29.35 (27.25–32.25) ± 0.87 | 23.95 (22.25–26.25) ± 0.70 | 11.35 (10.50–12.25) ± 0.34 | 25.10 (23.0–28.75) ± 0.99 | 23.75 (21.25–26.25) ± 0.85 | 23.55 (21.75–26.25) ± 0.84 | 23.45 (18.75–29.75) ± 1.9 | 15.35 (12.75–17.75) ± 0.94 | 10.4 (7.75–13.75) ± 1.1 | Absent | Absent |
| Ab | 99.45 (95.25–103.7) ± 1.4 | 27.60 (22.25–37.75) ± 2.7 | 25.90 (22.75–29.75) ± 1.2 | 10.55 (8.75–12.75) ± 0.68 | 29.55 (27.75–31.25) ± 0.60 | 24.75 (22.25–27.25) ± 0.97 | 25.80 (22.25–30.25) ± 1.39 | 25.45 (18.75–29.75) ± 1.86 | 15.75 (12.75–17.25) ± 0.83 | 9.55 (7.75–12.25) ± 0.93 | Absent | Absent | |
| Physalis angulata | Ad | 59.53 (52.0–75.50) ± 4.53 | 26.40 (25.25–27.25) ± 0.33 | 26.05 (25.25–27.25) ± 0.34 | 9.55 (8.25–10.75) ± 0.46 | 26.05 (25.25–27.25) ± 0.33 | 24.05 (22.75–25.75) ± 0.62 | 59.75 (51.50–76.0) ± 4.52 | 27.30 (25.75–30.25) ± 0.89 | 13.15 (12.75–13.75) ± 0.16 | 6.95 (5.25–8.25) ± 0.53 | Absent | Absent |
| Ab | 43.90 (26.75–51.50) ± 4.81 | 26.0 (24.75–27.25) ± 0.44 | 25.45 (24.75–26.25) ± 0.24 | 3.75 (3.00–4.75) ± 0.28 | 25.70 (25.25–26.25) ± 0.16 | 26.0 (25.25–26.75) ± 0.27 | 37.45 (26.50–52.25) ± 4.97 | 24.85 (22.75–26.50) ± 0.70 | 23.0 (21.25–25.75) ± 0.80 | 7.15 (5.25–9.75) ± 0.93 | Absent | Absent | |
| Ranunculus sceleratus | Ad | 54.15 (47.75–61.25) ± 2.34 | 41.0 (33.75–47.25) ± 2.53 | 34.25 (32.75–36.25 ± 0.65 | 9.85 (8.75–11.25) ± 0.40 | 34.05 (32.75–35.25) ± 0.43 | 24.85 (23.0–26.75) ± 0.71 | 50.20 (42.75–54.50) ± 2.1 | 32.40 (25.25–38.75) ± 2.40 | 21.30 (20.25–22.25) ± 0.3 | 7.50 (6.25–8.75) ± 0.41 | Absent | Absent |
| Ab | 64.05 (60.25–67.25) ± 1.21 | 52.25 (50.25–54.75) ± 0.85 | 32.15 (28.75–34.75) ± 1.04 | 10.70 (8.50–12.75) ± 0.88 | 31.50 (27.75–34.75) ± 1.89 | 27.45 (25.25–29.75) ± 0.81 | 53.40 (47.75–59.0) ± 1.89 | 35.85 (27.75–42.75) ± 3.07 | 20.25 (18.75–21.25) ± 0.47 | 7.50 (5.25–9.76) ± 0.83 | Absent | Absent | |
| Ricinus communis | Ad | 40.50 (38.75–42.25) ± 0.60 | 17.0 (13.75–20.25) ± 1.05 | 33.75 (31.25–38.75) ± 1.31 | 19.05 (17.25–21.0) ± 0.71 | 32.85 (31.25–34.25) ± 0.53 | 18.75 (16.25–21.0) ± 0.89 | 19.85 (16.25–23.75) ± 1.2 | 9.5 (8.0–12.25) ± 0.74 | 20.70 (18.75–23.0) ± 0.71 | 8.15 (6.75–10.25) ± 0.62 | Absent | Absent |
| Ab | 35.15 (32.75–37.75) ± 0.88 | 18.05 (13.75–24.75) ± 1.83 | 27.40 (25.50–28.75) ± 0.65 | 7.55 (6.25–8.75) ± 0.46 | 26.6 (24.75–28.75) ± 0.75 | 15.05 (12.75–17.25) ± 0.81 | 29.15 (26.25–30.75) ± 0.79 | 11.85 (10.25–13.75) ± 0.69 | 13.65 (11.25–15.25) ± 0.69 | 6.60 (5.75–7.75) ± 0.38 | Absent | Absent | |
| Sambucus nigra | Ad | 61.75 (58.75–63.75) ± 0.85 | 45.05 (38.75–49.75) ± 1.92 | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent | Absent |
| Ab | 63.75 (61.25–65.25) ± 0.68 | 35.65 (32.75–38.75) ± 1.10 | 42.95 (41.25–44.75) ± 0.60 | 11.45 (10.25–12.75) ± 0.46 | 46.95 (43.75–49.75) ± 1.15 | 34.55 (32.75–36.25) ± 0,64 | 49.55 (47.75–51.25) ± 0.60 | 23.75 (22.75–24.75) ± 0.35 | 26.65 (25.25–27.75) ± 0.43 | 13.75 (12.25–14.75) ± 0.41 | 118.25 (113.7–123.7) ± 1.9 | 24.85 (23.75–26.25) ± 0.43u | |
| Solanum nigrum | Ad | 69.55 (67.75–71.25) ± 0.64 | 30.15 (28.75–31.25) ± 0.43 | 29.80 (28.75–31.25) ± 0.45 | 7.90 (6.25–9.50) ± 0.56 | 29.80 (28.75–31.25) ± 0.45 | 19.10 (17.75–20.25) ± 0.43 | 29.75 (28.75–31.25) ± 0.47 | 24.50 (23.75–25.25) ± 0.27 | 17.25 (16.25–18.25) ± 0.35 | 1.85 (1.25–2.75) ± 0.29 | 255.5 (226.2–288.7) ± 11.7 | 33.45 (31.25–35.25) ± 0.75 |
| Ab | 67.75 (64.75–71.75) ± 1.55 | 37.15 (35.75–38.75) ± 0.53 | 27.35 (26.25–28.75) ± 0.43 | 7.30 (6.25–8.75) ± 0.45 | 27.35 (26.25–28.75) ± 0.43 | 16.85 (16.25–17.75) ± 0.29 | 40.35 (38.75–42.75) ± 0.76 | 13.0 (11.50–14.75) ± 0.57 | 17.75 (16.25–19.75) ± 0.61 | 2.25 (1.25–2.75) ± 0.27 | 229.1 (138.7–275.2) ± 24.0 | 39.85 (33.75–48.75) ± 2.47 | |
| Solanum incanum | Ad | 66.75 (65.25–68.75) ± 0.65 | 12.25 (11.25–13.25) ± 0.35 | 21.65 (20.25–22.75) ± 0.43 | 8.0 (7.25–9.0) ± 0.37 | 21.55 (20.25–22.75) ± 0.43 | 14.25 (12.75–15.25) ± 0.44 | 28.15 (26.25–29.75) ± 0.62 | 14.45 (13.25–15.25) ± 0.40 | 14.05 (12.75–15.25) ± 0.43 | 7.05)6.25–7.75) ± 0.25 | 218.2 (210.25–225.25) ± 2.85 | 17.1 (15.25–18.75) ± 0.64 |
| Ab | 34.45 (32.75–36.25) ± 0.60 | 14.15 (12.75–15.25) ± 0.43 | 14.15 (12.75–15.25) ± 0.43 | 6.15 (5.25–7.25) ± 0.40 | 14.15 (12.75–15.25) ± 0.43 | 11.35 (10.25–12.75) ± 0.43 | 27.95 (26.25–29.75) ± 0.60 | 14.10 (12.75–15.25) ± 0.43 | 6.65 (5.25–7.75) ± 0.43 | 5.25 (4.25–6.25) ± 0.35 | 236.0 (224.75–247.75) ± 3.7 | 22.85 (21.25–25.25) ± 0.73 | |
| Sorghum halepense | Ad | 85.20 (64.75–100.2) ± 6.8 | 21.30 (18.75–24.75) ± 1.03 | 32.05 (29.75–34.75) ± 0.81 | 10.30 (8.75–11.75) ± 0.55 | 31.90 (30.25–33.0) ± 0.50 | 19.45 (17.75–20.75) ± 0.53 | 61.9 (52.75–67.75) ± 2.46 | 22.80 (2125–25.25) ± 0.69 | 13.85 (12.75–15.25) ± 0.50 | 3.40 (2.75–4.25) ± 0.26 | Absent | Absent |
| Ab | 47.95 (46.25–49.75) ± 0.60 | 34.15 (32.75–35.25) ± 0.43 | 32.95 (31.25–34.75) ± 0.60 | 10.40 (8.0–12.25) ± 0.85 | 32.75 (31.25–34.75) ± 0.65 | 23.05 (21.75–24.75) ± 0.53 | 44.40 (42.75–46.25) ± 0.61 | 24.85 (23.75–26.50) ± 0.49 | 22.20 (21.25–23.0) ± 0.32 | 4.50 (3.75–5.25) ± 0.25 | Absent | Absent | |
| Thevetia peruviana | Ad | 35.65 (33.75–37.75) ± 0.67 | 28.25 (25.25–31.25) ± 1.10 | Absent | Absent | ||||||||
| Ab | 45.70 (41.25–52.25) ± 2.1 | 29.10 (26.25–22.75) ± 1.3 | 25.85 (23.75–27.75) ± 0.79 | 4.85 (3.75–6.25) ± 0.43 | 25.60 (23.75–27.75) ± 0.69 | 15.45 (13.75–17.25) ± 0.60 | 43.0 (38.75–48.75) ± 1.64 | 22.50 (18.75–28.75) ± 1.79 | 12.85 (11.25–14.75) ± 0.64 | 7.70 (5.50–10.25) ± 0.85 | Absent | Absent | |
| Trifolium repens | Ad | 30.35 (24.75–36.25) ± 1.90 | 21.25 (18.75–23.75) ± 0.92 | 17.95 (16.25–19.75) ± 0.60 | 5.20 (4.50–6.25) ± 0.30 | 17.95 (16.25–19.75) ± 0.60 | 12.30 (11.25–13.25) ± 0.33 | 34.70 (33.75–35.50) ± 0.32 | 17.15 (15.25–18.75) ± 0.62 | 9.85 (8.75–11.25) ± 0.43 | 3.60 (3.0–4.25) ± 0.21 | Absent | Absent |
| Ab | 42.35 (41.25–43.75) ± 0.43 | 30.15 (28.75–31.25) ± 0.43 | 20.25 (17.75–23.75) ± 1.04 | 7.20 (6.25–8.0) ± 0.32 | 21.85 (17.75–24.75) ± 1.20 | 14.55 (13.75–15.25) ± 0.25 | 44.95 (43.75–46.25) ± 0.40 | 27.20 (25.75–29.0) ± 0.57 | 10.50 (8.75–12.25) ± 0.60 | 4.85 (3.75–6.25) ± 0.43 | Absent | Absent |
SE, standard error.
Leaf epidermal morphology plays a crucial role in plant taxonomy and systematics. The quantitative attributes of leaf epidermal cells were measured in terms of their width and length on both the abaxial and adaxial surfaces. The maximum length of epidermal cells was observed on the lower surface, while the maximum width was observed on the upper surface. For example, E. helioscopia had the maximum length of epidermal cells (99.50 ± 9.02 μm) on the adaxial surface, whereas I. carnea had the lowest length (29.25 ± 1.31 μm). Similarly, the maximum width of epidermal cells was observed in S. nigra (45.05 ± 1.9 μm), while the lowest width was observed in S. incanum (12.25 ± 0.35 μm). Subsidiary cells, which are present alongside epidermal cells, also exhibited variations in width and length on both surfaces. S. halepense had the maximum length of subsidiary cells (61.9 ± 2.46 μm) on the adaxial surface, while R. communis had the lowest length (19.85 ± 1.2 μm). The maximum width of subsidiary cells was observed in Ranunculus sceleratus (32.40 ± 2.4 μm), while the minimum width was observed in E. helioscopia (7.9 ± 0.36 μm). On the abaxial surface, A. mexicana had the highest length of subsidiary cells (60.85 ± 4.02 μm), while I. carnea had the shortest length (23.40 ± 0.40 μm). Similarly, the highest width of subsidiary cells was observed in A. mexicana (37.95 ± 1.27 μm), while the lowest width was observed in E. helioscopia (9.50 ± 0.50 μm).
Variations in the width and length of stomatal pore and guard cells on the abaxial and adaxial sides were also observed in this study. On the adaxial surface, Alocasia macrorrhizos had the maximum length of stomata (34.30 ± 0.69 μm), while the minimum length of stomata was observed in E. Helioscopia (16.50 ± 1.0 μm). The highest width of stomatal length was observed in E. Royleana (29.85 ± 0.69 μm) and the lowest in E. Helioscopia (2.75 ± 0.14 μm). On the abaxial side, S. Nigra (46.95 ± 1.15 μm) had the maximum length of stomata, while the minimum length of stomata was examined in the following three plants: S. incanum (14.15 ± 0.4 μm), I. carnea (14.15 ± 0.36 μm) and B. monosperma (14.15 ± 0.36 μm). The highest width of stomata was observed in S. nigra (34.55 ± 0.64 μm) and the lowest in E. helioscopia (2.75 ± 0.14 μm). On the upper side, the highest length of guard cell was detected in A. macrorrhizos (34.60 ± 0.64 μm) and B. monosperma (14.15 ± 0.36 μm). On the other hand, the highest width of guard cell was found in E. Helioscopia (19.50 ± 0.50 μm) and the lowest in T. repens (5.20 ± 0.30 μm). On the lower surface, the extreme length of guard cells was examined in S. Nigra (42.95 ± 0.60 μm), while the lowest length of guard cells was observed in B. monosperma (14.15 ± 0.36 μm), I. carnea (14.15 ± 0.36 μm) and S. incanum (14.15 ± 0.43 μm). Similarly, the highest width of guard cell was observed in E. helioscopia (20.25 ± 0.61 μm), while the lowest was found in T. repens (3.75 ± 0.28 μm).
Trichomes also vary in length and width. On the adaxial side, the highest length of trichome was found in E. helioscopia (895.2 ± 70 μm) and I. carnea (39.55 ± 0.60 μm). On the other hand, the highest width of trichomes was observed in B. versicolor (46.40 ± 1.93 μm), while C. tinctoria (10.45 ± 1.05 μm) was found to have the lowest width of trichomes. On an abaxial surface, the maximum length of trichomes was found in Brugmansia versicolor (307.35 ± 2.62 μm), while the minimum was identified in Chenopodium ambrosioides (57.70 ± 2.28 μm). The highest width of trichomes was observed in S. nigrum (39.85 ± 2.47 μm), while the lowest was found in C. tinctoria (9.95 ± 0.40 μm).
The qualitative attributes of foliar epidermal anatomy showed significant variations among the studied plant species. Epidermal cells exhibited different shapes, including irregular, isodiametric polygonal, curvy and rectangular. Rectangular-shaped epidermal cells were present on both surfaces of S. halepense and on the adaxial surface of S. incanum. The pattern of AW also varied, ranging from deeply sinuous, wavy to sinuous, undulate, straight and angular. Thick sinuous walls were observed only in S. halepense. Stomata, which are crucial for gas exchange in plants, were observed on both surfaces of the leaves. The upper surface generally had a higher number of stomata than the lower surface. Different types of stomata were identified in the present study, including anisocytic, anomocytic, paracytic and cyclocytic. Cyclocytic stomata were found only in I. carnea. Anisocytic stomata have been observed in members of the Solanaceae family. Some species exhibited elliptical and wide elliptical stomatal pores. Dumbbell-shaped guard cells were observed only in S. halepense. Trichomes, or plant hairs, are another important aspect of leaf anatomy that can vary significantly among different plant species. Various types of trichomes were observed, including glandular trichomes and non-glandular trichomes. Glandular trichomes were found in Datura, which secrete toxic substances. Non-glandular trichomes, which do not produce any secretions, were observed in plants such as R. communis and S. nigrum. The density of trichomes also varied, with some plants having a sparse distribution, while others had a dense coverage of trichomes on leaf surfaces. For example, Datura innoxia exhibited a high density of glandular trichomes, giving the leaves a rough texture, while S. nigrum had a lower density of non-glandular trichomes, and thus a smoother leaf surface. The identified anatomical characteristics play a significant role in distinguishing and identifying poisonous species. The consistent presence or absence of specific characteristics in our study can serve as valuable diagnostic traits for species identification. For example, in our study, we consistently observed irregular epidermal cells with undulate AW, anomocytic stomata and glandular multicellular trichomes in the species of Solanaceae. This combination of features may serve as a distinguishing characteristic for species within this family. By highlighting these consistent features, we provide taxonomists with specific anatomical traits that can be used as diagnostic tools. These traits can be incorporated into identification keys or guides, enabling accurate species identification based on the microscopic examination of leaf epidermal characteristics.
The present study aimed to explore and compare the foliar anatomy of selected species, shedding light on the structural variations and adaptations present in their leaves. Based on the examination of the abaxial side, irregular epidermal cells with undulate AW and anomocytic stomata were observed in Solanaceae species, which is consistent with the findings of Adedeji et al. (2007). Ibrahim et al. (2016) reported rectangular-shaped epidermal cells with undulate cell walls in D. innoxia on both surfaces, whereas the present study revealed irregular and polygonal-shaped epidermal cells. The presence of anomocytic and anisocytic stomata was consistent with the findings of Ibrahim et al. (2016), and multicellular non-glandular trichomes were also observed. In S. nigrum, polygonal epidermal cells with a wavy pattern of AW on the upper surface and irregular cells with sinuous patterns on the lower surface were observed, which aligns with the findings of previous studies except for the undulate AW on the lower surface. The presence of anisocytic and anomocytic stomata, along with multicellular non-glandular trichomes, was consistent with the findings of previous research. Zahra et al. (2014) studied various Euphorbiaceous species and observed irregular epidermal cells with undulating walls and anisocytic stomata in E. pulcherrima, which is similar to the findings of the present study. Multicellular non-glandular trichomes with bulbous bases were also observed, consistent with the findings of previous work. In E. royleana, the observed shape of epidermal cells was polygonal, and paracytic stomata with straight AW were found only on the abaxial side. These results deviate from those of previous studies, which reported different-shaped epidermal cells with diacytic stomata. Najmaddin (2020) reported E. helioscopia with tetracytic and anomocytic stomata on the abaxial surface, while the current research identified polygonal and irregular epidermal cells with undulating and entire walls, and retained anomocytic stomata. Tyagi et al. (2013) examined the transverse section of R. communis, observing collenchyma, microcrystals, oil glands, parenchyma, palisade layers, prismatic crystals and rosette crystals, but there has been no additional foliar anatomical work on R. communis. The present study examined polygonal epidermal cells with straight AW and paracytic stomata on both surfaces.
Ramzan et al. (2019) previously described the anatomical characteristics of B. monosperma and found the absence of stomata on the adaxial surface and paracytic stomata on the abaxial surface, which is consistent with the current findings. Glandular, unicellular trichomes with pointed tips were also observed, which were not reported by the earlier work. However, the present research identified irregular and polygonal epidermal cells, which deviates from the previous study. Gostin (2009) observed foliar cross-sections of T. repens, noting palisade and parenchyma cells, but unfortunately, there is no epidermal anatomical study found in the literature. The current study revealed irregular and polygonal epidermal cells with anomocytic and anisocytic stomata on both the adaxial and abaxial surfaces, along with glandular multicellular trichomes.
In Ranunculus sceleratus, irregular epidermal cells with sinuous AW and anomocytic stomata were observed on both the abaxial and adaxial surfaces, with no trichomes recorded, which is consistent with the results of Salim et al. (2016). Bashir et al. (2020) examined irregular and polygonal epidermal cells with wavy to straight AW and paracytic stomata in T. peruviana, while the present study identified anisocytic stomata, which was not reported in the literature. Trichomes were not found in both the current and recent research. Arogundade and Adedeji (2019) recently investigated polygonal epidermal cells with straight walls, while brachyparacytic stomata were observed in Alocasia macrorrhiza in previous work, whereas the present study found paracytic stomata. In S. halepense, sinuous walls of rectangular epidermal cells with paracytic stomata were noted, which is consistent with the finding of Chaudhari et al. (2014). Only S. halepense exhibited dumbbell-shaped guard cells in all the mentioned varieties. The abaxial surface of Duranta erecta exhibited polygonal-shaped epidermal cells, which was also observed by Shekhawat and Manokari (2017). Gaafar (2019) observed wavy polygonal and irregular epidermal cells with only anisocytic stomata in Chenopodium ambrosioides, while the present results showed anisocytic stomata and a wide elliptical shape of the stomatal pore. Al-Mousawi et al. (2019) inspected thick anticlinal-walled epidermal cells and anisocytic stomata in A. mexicana, whereas the present study showed polygonal epidermal cells with thin AW and anomocytic stomata.
This research exhibited irregular or rectangular epidermal cells with slightly sinuous AW, along with cyclocytic stomata, in I. carnea. Both glandular capitate and non-glandular unicellular conical-shaped trichomes were also observed. These outcomes are consistent with the previous work of Ashfaq et al. (2019). Koyuncu et al. (2008) recorded polygonal epidermal cells with anisocytic stomata in P. harmala, while the present study described anomocytic stomata, showing slight deviations from prior work. Amini et al. (2019) examined the foliar cross-section of S. nigra and observed parenchyma cells and vascular bundles. Atkinson and Atkinson (2002) examined the high density of stomata on the abaxial surface and the absence of stomata on the adaxial surface. In contrast, the present study revealed polygonal epidermal cells with angular walls, exhibiting anomocytic stomata and multicellular trichomes, which were not mentioned in the literature.
It is important to explore why there are variations in the anatomical features observed in different studies. Factors such as genetic variability, environmental conditions, geographic location and different plant developmental stages could contribute to the observed differences. By focussing on these anatomical characteristics, our research contributes to the understanding of plant diversity and species identification. The consistent traits can be incorporated into taxonomic keys, guides and databases, enabling accurate and efficient identification of poisonous species. Additional research and comparative studies are needed to validate the diagnostic value of these anatomical characteristics. However, our findings lay the foundation for future investigations and provide a starting point for researchers and taxonomists interested in the identification and classification of poisonous species based on leaf anatomical features.
Overall, understanding the foliar anatomy of poisonous plants provides valuable information for their identification and classification. By recognising specific morphological features, dermal structures, glandular structures, secondary metabolites and leaf colouration, botanists, toxicologists and other experts can effectively distinguish poisonous plants from non-toxic species, contributing to public safety and environmental management.
This research article demonstrates the successful identification of poisonous plants through the analysis of foliar micromorphology using LM and SEM techniques. This study highlights the efficacy of these methods in distinguishing toxic plant species based on their unique microscopic features. Furthermore, the identification methodology presented in this article has significant implications for public health and safety. As research progresses, the integration of advanced technologies and increased public awareness will play a vital role in safeguarding individuals from the hazards posed by these plants, ultimately promoting public safety and well-being. In the future, research based on hazardous plant identification using DNA barcoding and phytotoxicity testing, as well as phylogenetic analysis, will be required.