Plant diversity in botanical gardens plays a vital role in conservation, education, and research, especially in urban areas. This study assesses tree species diversity, regeneration potential and stakeholders' perception in National Botanical Garden, Mirpur, Dhaka. A total of 220 tree species from 61 families were recorded using a stratified random quadrat method (10 x 10 m). Among these, 59% were native and 41% exotic. The most abundant and dominant species were Swietenia mahagoni (L.) Jacq., Acacia auriculiformis A. Cunn. ex Shannon-Wiener, Simpson's, and Margalef's Diversity Indices were 1.97, 0.82 and 28.2, respectively, indicating moderate diversity and low evenness. Zone 1 of the garden showed the highest diversity, while Zones 1, 9, and 12 had the greatest number of exotics in their top ten dominant species. High Jaccard Similarity between zones suggested repetition in species composition. Regeneration was low, with only seven species showing seedling development. Dipterocarpus alatus Roxb. had the highest seedling density and Hopea odorata Roxb. showed the best recruitment success. Stakeholder surveys revealed strong support for increasing native species, planting more wildlife-supporting trees, and involving experts in garden management. Identified threats include poor planning, exotic dominance, and lack of awareness. Key recommendations include enhancing native diversity, lowering spatial repetition of similar species, introducing rare species, and improving expert-led management to ensure ecological sustainability.
Prasoxylon excelsum (Spreng.) Mabb., a medicinal tree of the family Meliaceae, is traditionally used to treat diarrhoea, dysentery, and food poisoning. Despite its ethnobotanical significance, no genomic resources have been available to date. This study presents the first de novo assembly and characterization of both the chloroplast (Cp) and nuclear genomes of P. excelsum. The complete Cp genome spans 160,299 bp and exhibits a typical quadripartite structure, comprising a large single-copy (LSC) region of 87,832 bp, a small single-copy (SSC) region of 18,360 bp, and a pair of inverted repeats (IRs) of 27,054 bp each. The plastome encodes 81 protein-coding genes, 37 transfer RNAs, and eight ribosomal RNAs. A total of 98 simple sequence repeats (SSRs) were identified, predominantly mononucleotide motifs (68). Nucleotide diversity analysis revealed atpB and ycf1 as the most variable regions, suggesting their potential as DNA barcodes. Phylogenetic reconstruction using the maximum-likelihood method confirmed the placement of P. excelsum within the subfamily Melioideae. Molecular dating analysis indicated that P. excelsum diverged during the late Burdigalian age of the Miocene epoch, approximately 16.21 million years ago. The nuclear genome assembly totaled 676.45 Mb with an N50 of 3,686 bp, showing 87.8% BUSCO completeness. Gene prediction identified 44,465 genes, with KEGG analysis indicating enrichment in metabolic pathways. These findings provide a valuable foundation for evolutionary, phylogenomic, and functional studies in Prasoxylon and related Meliaceae species, aiding future research in conservation genomics, phytochemistry, and molecular breeding.
A total of 10 taxa of blue-green algae have been included as new records for Bangladesh. These include Anabaena spiroides Klebahn, Arthrospira platensis fa. granulata Desikachary, Cylindrospermopsis curvispora M. Watanabe, Gomphosphaeria fusca Skuja, G. nageliana (Unger) Lemmermann, G. rosea (J.W.Snow) Lemmermann, Lyngbya circumcreta G.S. West, Pseudanabaena minuta Skuja, Spirulina labyrinthiformis (Menegh.) Gom. and Xenococcus minumus fa. starmachii Geitler. from some wetlands of Lalmai Hill areas in Cumilla district of Bangladesh.
Palynomophological and anatomical characters of the section Mesocentron (Asteraceae) from T & uuml;rkiye was investigated and compared using microscopically techniques. The studied taxa have radially symmetrical, monad, isopolar, sometimes heteropolar, and generally 3-colporate, occasionally 4-colporate pollen grains. Only prolate pollen shaped pollen grains were observed in all of the studied species. While the colpus and porus morphology of pollen grains were the same in studied taxa the density of spinule on the pollen were changeable. It was observed that the basic anatomical structures of the sections obtained from the trunk anatomy were the same, but it was determined that the cellular sizes differed significantly between species. It has been emphasized that the combined use of pollen and anatomical characters may be effective in distinguishing these species.
The present study marks the first molecular characterization of Humaria hemisphaerica (F.H. Wigg.) Fuckel from the temperate Oghi forest of Khyber Pakhtunkhwa, Pakistan, a region known for its ecological richness and underexplored fungal diversity. A comprehensive description of both the macro-and micro-morphological characteristics is included, supplemented with color photographs of fresh ascocarp in natural habitat and microscopic images with main anatomical features. Phylogenetic analysis of the studied sample was conducted using internal transcribed spacer (ITS) of nrDNA. This analysis supports the taxonomic identification of H. hemisphaerica and confirms its phylogenetic position. Additionally, comparisons are made with closely related taxa that exhibit phenotypic and molecular similarities. This is the first molecular description of this taxon occurring in Pakistan.
Phlomis sieheana and P. armeniaca species are known as two close taxa that are confused with each other when firstly observed in their natural habitats. In the current investigation, the morphological features of Phlomis sieheana and P. armeniaca belonging to the Lamiaceae family have been revised and their anatomical, palynological and micromorphological features have been presented. The pollen grains of the studied species are monad, isopolar, and radially symmetrical. The pollen shape of P. sieheana is subprolate, while P. armeniaca is prolate-spheroidal. Also, exine sculpture was observed as reticulate-perforate in both species. However, the types of pollen aperture of the species are determined differently. P. sieheana has pollen grains with tricolpate apertures, while P. armeniaca has both tricolpate and syncolpate ones. Nutlet micromorphology contains characters that support the differentiation of species. The nutlet coat is rugulate in Phlomis sieheana and reticulate in P. armeniaca. The characteristics of anatomical, palynological and micro morphological in P. sieheana and P. armeniaca are found valuable supporting the separation of these species.
Tropical swamp forests are dynamic ecosystems where water quality is closely linked to ecological integrity. The Ratargul Swamp Forest in Bangladesh faces increasing anthropogenic and environmental pressures, but a comprehensive ecological assessment integrating biological and physicochemical indicators is lacking. The present study was conducted to evaluate its ecological status, identify key environmental drivers, and assess the utility of financial groups (FGs) as bioindicators for conservation. In the present study, the ecological condition of the forest was assessed by integrating phytoplankton FGs with the water quality index (WQI) and the chlorophyll-based trophic state index [TSI (Chl)] during the pre-monsoon and post-monsoon seasons. A total of 54 phytoplankton species were identified from the swamp forest, with Euglenophyta dominating the assemblage. Functional group W1 (Euglena sp., Euglena mutabilis, E. rostrifera, E. viridis, E. oblonga, E.acus, E. polymorpha, E. chordata, E. allorgei, E. deses, Phacus sp., Phacus longicaudus. Strombomonas sp., Synura sp. and Astasia sp.) associated with organic pollution and high biological oxygen demand (BOD), were the most abundant in both seasons, with a marked increase post-monsoon. Redundancy analysis (RDA) revealed that soluble reactive phosphorus (SRP), soluble reactive silicate (SRS), and conductivity were the key environmental drivers influencing the composition of FGs. The water quality of the swamp forest was poor, as indicated by the WQI, which was based on the selection of water quality parameters (R2 = 0.85). The TSI (Chl) supported the WQI result, indicating the eutrophic status of the forest. The present research findings showed that phytoplankton functional groups, when integrated with water quality indices, offer a robust and sensitive approach to ecological monitoring and planning conservation strategies for tropical swamp forest wetland ecology.
Sapota (Manilkara zapota is an economically important fruit crop in Bangladesh that was affected by the different types of red colored leaf spot symptoms from 2019 to 2021. The study aimed to characterize red colored leaf spot symptoms of sapota by morphological and molecular analysis. Infected sapota were collected from three southern coastal districts of Bangladesh. Causal organism of the disease was isolated for morphological and molecular characterization. After 24 months of the plantation, about 70% disease prevalence in the experimental areas was recorded. The present investigation suggested that symptoms were caused by Neopestalotiopsis sp. Phylogenetic analysis using the internal transcribed spacer (ITS) region of ribosomal DNA additionally confirmed Neopestalotiopsis sp. in red leaf spot symptoms of sapota. For further validation, a pathogenicity test was carried out using three isolates on six months old saplings under Net-house conditions, and same symptom was developed in inoculated leaves after 14 days inoculation. The present investigation confirmed the outbreak of sapota red leaf spot disease, caused by Neopestalotiopsis sp. in Bangladesh. Bangladesh J. Plant Taxon. 32(1): 53-64, 2025 (June)
The present paper deals with seven seaweeds taxa namely, Blidingia minima (Kützing) Kylin, Bryopsis pennata Lamouroux and Halimeda simulans Howe from Chlorophyceae; Dictyopteris plagiogramma (Montagne) Vickers and Padina perindusiata Thivy from Phaeophyceae and Galaxaura obtusata (Ellis & Solander) Lamouroux and Liagora valida Harvey from Rhodophyceae have been identified, described, and illustrated as new records for Bangladesh. Of these, Blidingia is also a new generic record for Bangladesh. Bangladesh J. Plant Taxon. 32(1): 77-82, 2025 (June)
Elephant rope (Sterculia villosa Roxb.) is a threatened plant species in Bangladesh. To conserve this threatened tree, research should be carried out on improvement of germination and early growth. Therefore, the objective of the study was to explore the effects of pre-sowing seed treatments on germination behavior and to assess the possibility of increasing the germination rate of Sterculia villosa. The seeds were subjected to nine pre-sowing treatments viz., T0: Seeds with no treatment (Control), T1: Seeds scrapping with sand paper at the distal end, Seeds immersed in T2: room temp. water for 24 hours, T3: hot water for 1 minute, T4: 10% concentrated H2SO4 for 1 minute, T5: 10% concentrated H2SO4 for 3 minutes, T6: 10% concentrated HCL for 1 minute, T7: 10% concentrated HCL for 3 minutes, T8: 200ppm GA3 for 24 hours, T9: Fungicide (Autostin 50 WDG) for 24 hours. The study conducted in the propagation house, revealed that pre-sowing treatments significantly (p<0.05) enhanced seed germination parameters of Sterculia villosa. Seed germination started within 2 days after seed sowing and continued up to 15 days. The highest germination percentage (50%) was observed in T8 and the lowest (20%) in T0, T3, and T7. The highest germination Index was found in T8 and the lowest in T0. T8 was found more effective in respect to faster germination, high germination percentage, germination index, seedling vigor index, speed, and energy of germination. In case of seedling growth parameters, the highest shoot length (62 cm) was found in T1 and the lowest (33 cm) in T3. Here, T1 was found more effective in case of shoot length, leaf number, leaf length, and leaf width. Bangladesh J. Plant Taxon. 32(1): 93-103, 2025 (June)
This study assessed whether the observed morphological variation among eight distinct forms of Duranta erecta in Nigeria reflects true genetic divergence or represents phenotypic plasticity within a single species. The forms are distributed across geo-political zones in Nigeria and were characterized based on leaf coloration, margin types, and branching architecture. These forms exhibit variations in their chemical compositions, suggesting potential differences in their DNA profiles. DNA was extracted from leaf samples of all eight morphological forms, and conventional PCR was employed to amplify three marker regions: ITS, matK, and rbcL. The amplified fragments were visualized on 1% agarose gel electrophoresis, sequenced, and analyzed phylogenetically using MEGA-11. The matK marker exhibited 100% sequence identity, indicating minimal variation among the forms. In contrast, rbcL and ITS displayed 99% sequence identity, with ITS revealing greater polymorphic variation. Phylogenetic tree analysis showed the highest support values for rbcL, followed by ITS and matK. The combined topologies generated from the three markers revealed no significant differences in the evolutionary history of the eight Duranta erecta forms. This result suggests a gene flow among the forms, confirming their classification as a single species. Bangladesh J. Plant Taxon. 32(1): 65-75, 2025 (June)
This study aims to examine chromosome morphologies of the genus Centaurea from Türkiye. Chromosome counts were performed during somatic metaphase using squash technique. The clearest metaphase stages were identified, and the chromosomes were analyzed using an imaging system. The chromosome number for C. solstitialis subsp. carneola was found to be 2n=18, while the other taxa were determined to have 2n=16. C. verutum is differentiated from other taxa with the same chromosome number based on its karyotype formula. In conclusion, it can be inferred that the data obtained from karyomorphological studies contribute to the differentiation of taxa. Bangladesh J. Plant Taxon. 32(1): 17-25, 2025 (June)
Agaricus species are ecologically and economically significant, yet their diversity in underexplored regions like Pakistan remains poorly documented. This study investigated Agaricus species from Bahawalnagar district, Punjab, Pakistan. Specimens were collected from different locations in Bahawalnagar, followed by morphological examination based on macroscopic and microscopic features. For molecular identification, DNA was extracted, and the ITS region of the nrDNA was sequenced. Phylogenetic analysis was conducted using Maximum Likelihood methods to determine the taxonomic placement of the species under investigation. The newly discovered species is morphologically similar to A. dunensis, with a brownish-orange central disk and light brown squamules becoming sparser at the margins. Basidiospores were subglobose to broadly ellipsoid, measuring 3.9–4.8 × 3.1–4.1 μm, and the species displayed clavate to narrowly clavate cheilocystidia. Phylogenetic analysis of the ITS region confirmed the distinctiveness of this species within Agaricus sect. Minores. The findings highlight the diversity of macrofungi in this region, with this species representing a previously undocumented taxon. This discovery enhances knowledge of Pakistan's fungal diversity and emphasizes the importance of exploring understudied regions. Bangladesh J. Plant Taxon. 32(1): 83-92, 2025 (June)
A few of the plant specimens of the family Lauraceae Juss., previously collected from Bandarban and Habiganj districts and stored in DACB, were identified as Lindera assamica (Meisn.) Kurz and Litsea sericea (Wall. ex Nees) Hook.f. Another few specimens of the family Rubiaceae Juss., recently collected from the Lathitila forest of Moulvibazar during the floristic explorations conducted in the northeast region of Bangladesh, were determined to be Acraranthera tomentosa R.Br. ex Hook.f. These species are new to the flora of Bangladesh. Taxonomic descriptions of these species have been provided, together with information on their ecology, distribution, representative specimens examined, and illustrations or photographs. Bangladesh J. Plant Taxon. 32(1): 115-122, 2025 (June)
This study deciphers the first complete chloroplast (Cp) genome of Fraxinus griffithii C.B. Clarke (Oleaceae), a medicinally important tree species native to Bangladesh, providing new insights into its genome structure and phylogenetic relationships. The circular Cp genome comprises a total length of 155,683 bp with a large single-copy region (86,466 bp), small single-copy region (17831 bp), and two inverted repeat regions (51,386 bp). The plastome encodes 130 genes, including 86 protein-coding genes, 36 transfer RNAs and eight ribosomal RNAs. Comparative genomic analysis revealed genome divergence, similar genomic architecture, and lack of large rearrangements within the Oleaceae family. The plastome harbored 46 simple sequence repeats (SSRs) and 49 longer repeats. Among the identified SSRs, mononucleotides (39) were the most frequent, while palindromic repeats predominated among the longer repeats. Nucleotide diversity analysis revealed rpl32 and ndhF genes of the SSC region as the most hypervariable DNA barcodes. Plastome-wide phylogeny supported the systematic position of F. griffithii within the subtribe Fraxininae of the tribe Oleeae. Molecular dating analysis suggests that F. griffithii originated approximately 15.07 million years ago, during the Langhian stage of the Middle Miocene epoch in the Neogene period of the Cenozoic era. The findings of this study provide the first Cp genome data for F. griffithii (GenBank Accession: PP669282.1), contributing to valuable insights into the evolutionary genomics of the family Oleaceae. Bangladesh J. Plant Taxon. 32(1): 27–44, 2025 (June)
This study marks the first report of Lasiodiplodia theobromae associated with coconut in Bangladesh, a pathogen known to cause wide range of diseases crippling coconut production worldwide. Two isolates, Lt_BD 1 and Lt_BD 4, were obtained from coconut samples and subjected to comprehensive morpho-molecular and phylogenetic analyses. Morphological observations, including colony characteristics (color, texture, and surface appearance), growth patterns and conidial dimensions and shapes, preliminarily identified the isolates as Lasiodiplodia species. Molecular analysis, through PCR amplification of the internal transcribed spacer (ITS) regions, confirmed the identity of the isolates as L. theobromae. A phylogenetic tree, constructed using sequences of the studied isolates alongside 48 reference Lasiodiplodia species (retrieved from NCBI) and one out-group species (Pyricularia oryzae), corroborated this identification. This study provides a foundation for further rigorous research on the diseases of coconut caused by L. theobromae in Bangladesh. Bangladesh J. Plant Taxon. 32(1): 105-113, 2025 (June)
The new species Lycium mellitum J. Z. Dong (Solanaceae) is established and illustrated from Qinghai province of China. It has a close association with L. ruthenicum and L. ostrum J.Z. Dong, but is distinguished by several morphological characters: stems much branched, thorns at nodes or not, usually clustered with leaves and flowers; leaves narrowly linear, fleshy, gray, usually apically light yellow; pedicel 10-20 mm long; berries orange-yellow, nearly transparent, inside placenta faintly visible; seeds 1-5, rarely more, light brown. Bangladesh J. Plant Taxon. 32(1): 123-127, 2025 (June)
