P. Raja

@sjctni.edu

Research Associate, The Rapinat Herbarium (RHT)
St. Joseph's College (Autonomous), Tiruchirappalli

P. Raja

EDUCATION

PhD Botany

RESEARCH, TEACHING, or OTHER INTERESTS

Agricultural and Biological Sciences, Plant Science
18

Scopus Publications

169

Scholar Citations

6

Scholar h-index

3

Scholar i10-index

Scopus Publications

  • Taxonomic Notes on Iphigenia (Colchicaceae) From Tamil Nadu, India With Addition of Two New Species
    Lourdusamy John Peter Arulanandam, Prakasam Raja, Sebastian Soosairaj
    Feddes Repertorium, 2026
    The genus Iphigenia Kunth has been poorly recorded in the state of Tamil Nadu, India. In this research, we provide a detailed taxonomic account based on comprehensive field and herbarium investigations. Five species are recognized, each accompanied by detailed nomenclatural notes, morphological descriptions, photographic plates, and an identification key to Indian Iphigenia . This study integrates multiple lines of evidence, including leaf epidermal anatomy, pollen morphology, and seed characteristics examined under a scanning electron microscope (SEM), along with molecular data from sequencing the rbcL and trnL regions. Two new species, Iphigenia ehrhartii and I. balamii , are described herein. These species are closely related to I. sahyadrica but can be distinguished by their taller stature (> 10 cm), shorter pedicels, flowers ranging in color from purple to golden yellow, perianth lobes with fewer than five nerves, obovoid to cylindrical capsules, and ovoid to oblong seeds with a foveolate–curvilinear surface. Notably, they flower and fruit during December–January.
  • Sabdariffa pudukkottaiensis S. Soosairaj (Malvaceae), a New Species From the Scrub Forest of Tamil Nadu, India
    Sebastian Soosairaj, Prakasam Raja, Lourdusamy John Peter Arulanandam, Johny Kumar Tagore
    Feddes Repertorium, 2026
    A new species of Sabdariffa from the Pudukkottai district of Tamil Nadu, India, is described here. The proposed new species is morphologically allied to S. mastersianus (Hiern) Mwachala & R.L. Barrett; however, it differs in having prickles on the stem, petiole, and peduncle. It is also allied to S. radiata (Cav.) R.L. Barrett & M.N. Hanes in the presence of prickles, bifurcate epicalyx, and ovate calyx. But the new species differs in having a peduncle up to 40 mm and articulating just below the epicalyx (vs. up to 13 mm, articulating at base), staminal column < 18 mm and pubescent (vs. staminal column > 20 mm and glabrous), stipule > 10 mm long and ciliate along the margin (vs. stipule < 10 mm and entire margin). Sabdariffa pudukkottaiensis differs from H. furcata (Willd.) M.M. Hanes & R.L. Barrett have a longer peduncle at fruiting stage (vs. peduncle < 20 mm long in capsule), hispid below the articulation (vs. glabrous below the articulation), and calyx lobes tomentose towards the apex on both the surface (vs. calyx lobes with simple bristles without). An identification key to Sabdariffa of India is provided.
  • Anatomical and Micromorphological Features of an Endemic Geophyte Iphigenia mysorensis (Colchicaceae)
    L. John Peter Arulanandam, P. Raja, S. Soosairaj, R. Ambigadevi
    National Academy Science Letters, 2026
  • Ceropegia rapinatiana (Britto & Bruyns) Bruyns – An Endemic Species at the Verge of Extinction
    P. Raja, Johny Kumar Tagore, K. Thirumalai, P. Jansirani
    National Academy Science Letters, 2025
  • Reinstatement of Acalypha fallax Mull. Arg. and description of A. brittoi sp. nov. based on micromorphological and molecular characters
    Sebastian Soosairaj, Maria Soosai Mary Nithya, Prakasam Raja, Lourdusamy John Peter Arulanandam
    Nordic Journal of Botany, 2025
    In 1865, Müller Argoviensis proposed Acalypha fallax based on specimens from Peninsula Indiae orientalis, which is now considered synonymous with A. lanceolata Willd. A recent study conducted in Tamil Nadu, India, from 2019 to 2022 thoroughly examined Acalypha species using multiple criteria: leaf epidermal characteristics, seed morphology, pollen features observed via scanning electron microscopy (SEM), and sequencing of the ITS , rbcL and matK spacer regions. This work identified distinctions between A. fallax and A. lanceolata , such as longer peduncles, obovate bracts in male flowers, and stems with two types of trichomes: strigose and hirsute. Moreover, the study proposed a new species, A. brittoi , which is described here as distinguishable from A. fallax by its larger leaf blades with 13–14‐toothed margins (compared to smaller blades with 8–9‐toothed margins in A. fallax ), and by the ovate perianth of its male flowers (versus orbicular perianth in A. fallax ). Unique patterns of leaf epidermal crystals and granules on seed surfaces further aided in distinguishing A. fallax from A. brittoi . Molecular analysis additionally confirmed genetic differences among these three species.
  • Characterization of carbon fluxes, stock and nutrients in the sacred forest groves and invasive vegetation stands within the human dominated landscapes of a tropical semi-arid region
    R. V. Akil Prasath, R. Mohanraj, K. R. Balaramdas, A. Jhony Kumar Tagore, P. Raja, A. Rajasekaran
    Scientific Reports, 2024
    In the semi-arid plains of Southern India, outside the protected area network, sacred groves forests and the barren lands invaded by Prosopis juliflora are reckoned to be the major greenery, but have homogenous and heterogeneous vegetation respectively. This study attempted to compare 50 Sacred Groves Stands (SGS) and 50 monodominant Prosopis juliflora Stands (PJS) for the functional diversity, evenness, floral diversity, carbon stock and dynamics, carbon-fixing traits, dendrochronology of trees, soil nutrient profiles, and soil erosion. Quadrat sample survey was adopted to record stand density, species richness, abundance, basal area and leaf area index; composite soil samples were collected at depths 0–30 cm for nutrient profiling (N, P, K, and OC). Photosynthesis rate (µmole co2 m2/sec), air temperature (°c), leaf intracellular co2 concentration (ppm), ambient photosynthetic active radiation (µmole m2/sec), transpiration rate (m. mole H2O m2/sec) were determined for the 51 tree species existed in SGS and PJS using Plant Photosynthesis system. Structural Equation Model (SEM) was applied to derive the carbon sequestering potential and photosynthetic efficiency of eight dominant tree species using vital input parameters, including eco-physiological, morphological, and biochemical characterization. The Revised Universal Soil Loss Equation (RUSLE) model, in conjunction with ArcGIS Pro and ArcGIS 10.3, was adopted to map soil loss. Carbon source/sink determinations inferred through Net Ecosystem Productivity (NEP) assessments showed that mature SGS potentially acted as a carbon sink (0.06 ± 0.01 g C/m2/day), while matured PJS acted as a carbon source (−0.34 ± 0.12 g C/m2/day). Soil erosion rates were significantly greater (29.5 ± 13.4 ton/ha/year) in SGS compared to PJS (7.52 ± 2.55 ton/ha/year). Of the eight selected tree species, SEM revealed that trees belonging to the family Fabaceae [Wrightia tinctoria (estimated coefficient: 1.28, p = 0.02) > Prosopis juliflora (1.22, p = 0.01) > Acacia nilotica (1.21, p = 0.03) > Albizia lebbeck (0.97, p = 0.01)] showed comparatively high carbon sequestering ability.
  • Chlorophytum kolliense (Asparagaceae), a new species from the Eastern Ghats of Tamil Nadu, India
    Sebastian Soosairaj, Prakasam Raja, Balakrishnan Balaguru, Narayanasamy Dhatchanamoorthy
    Nordic Journal of Botany, 2024
    A new species of Chlorophytum is described and illustrated in this article. Morphological, root anatomical, pollen and molecular features were compared with its allied species C. laxum R.Br. which has apiculate anther, lanceolate bract, 16–18 nerved flat leaf and ellipsoid pollen with contrast to obtuse anther, ovate bract, 11–13 nerved conduplicate leaf and ovoid pollen. The molecular features complement the differences.
  • A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India
    Prakasam Raja, Lourdusamy John Peter Arulanandam, Sebastian Soosairaj, Kadher Althaf Ahammed Kabeer
    Adansonia, 2023
    Une espèce nouvelle de Justicia L. (Acanthaceae) du Tamil Nadu, Inde. Justicia tamilnadensis P.Raja & Soosairaj, sp. nov, une espèce nouvelle du Tamil Nadu, Inde, est décrite et illustrée ici. Elle est étroitement apparentée à J. salsoloides T.Anderson. Justicia tamilnadensis P.Raja & Soosairaj, sp. nov. est une plante herbacée prostrée avec une tige mince, vert pourpre, glabre et anguleuse; des feuilles elliptiques-oblongues, glabres, subsessiles; une corolle pubescente à l'intérieur de la gorge et des capsules subcylindriques avec un tomentum blanc alors que J. salsoloides est un petit sous-arbrisseau à tige rigide, blanche, tomenteuse et térébrante; feuilles spathulées ou oblongues-lancéolées, subglabres, sessiles; corolle glabre à l'intérieur et capsules comprimées avec un tomentum brun. La clé d'identification de Justicia L. du Tamil Nadu, le statut de conservation (En danger critique d'extinction) et la carte de répartition de J. tamilnadensis P.Raja & Soosairaj, sp. nov. sont également fournis.
  • Theriophonum blumei (Araceae), a new species from Tamil Nadu, India
    Lourdusamy John Peter Arulanandam, Sebastian Soosairaj, Prakasam Raja, Balakrishnan Balaguru
    Nordic Journal of Botany, 2023
    Theriophonum blumei sp. nov., a new species is described and illustrated from Tamil Nadu, India based on morphological and leaf epidermal features. Although morphologically T. blumei appears to be similar to T. sivaganganum (Ramam. & Sebastine) Bogner having long acuminate spathe, it is different from T. sivaganganum in various aspects such as ellipsoid seed with ridged surface, spinulose and bifid stigma, filiform neuters and berries with purplish strands. T. blumei has echinate pollen sculpture and T. sivaganganum has verrucate sculpture. Added to that, molecular based ( rbcL , matK , trnL‐F ) phylogenetic analysis also indicate that T. blumei is genetically distinct from T. sivaganganum .
  • DISTRIBUTION OF LINDERNIA MINIMA (BENTH.) MUKERJEE (FAMILY LINDERNIACEAE): AN ENDANGERED AND ENDEMIC HERB FROM TAMIL NADU, INDIA
    Prakasam Raja, Sebastian Soosairaj, Narayanasamy Dhatchanamoorthy
    Journal of the Bombay Natural History Society, 2022
  • Lepidagathis decumbens N. Dhatchan. & S. Soosairaj, sp. nov. (Acanthaceae), a new species from Tamil Nadu, India
    Narayanasamy Dhatchanamoorthy, Chinnasamy Karthikeyan, Prakasam Raja, Sebastian Soosairaj, Natesan Balachandran
    Adansonia, 2022
  • Solanum pulneyensis Soosairaj, sp. nov. (Solanaceae) from Palani Hills National Park of Tamil Nadu, India
    Sebastian Soosairaj, Prakasam Raja, Balakrishnan Balaguru, Johny Kumar Tagore
    Adansonia, 2021
  • New distribution record of two endemic plant species, Euphorbia kadapensis Sarojin. & R.R.V. Raju (Euphorbiaceae) and Lepidagathis keralensis Madhus. & N.P. Singh (Acanthaceae), for Karnataka, India
    P. Raja, N. Dhatchanamoorthy, S. Soosairaj, P. Jansirani
    Journal of Threatened Taxa, 2020
  • A new species of dalbergia (Fabaceae: Dalbergieae) from Tamil Nadu, India
    S. SOOSAIRAJ, P. RAJA, S. JOHN BRITTO, B. BALAGURU
    Phytotaxa, 2018
  • Derris gamblei sp. nov. (Fabaceae) from Tamil Nadu, India
    P. Raja, S. Soosairaj, N. Dhatchanamoorthy, J. K. Tagore
    Nordic Journal of Botany, 2017
  • Two additions to the flora of the Palni Hills, southern India
    S. Soosairaj, P. Raja, B. Balaguru, T. Dons
    Journal of Threatened Taxa, 2016
  • Green synthesis of copper bionanoparticles to control the bacterial leaf blight disease of rice
    Antonysamy Kala, Sebastin Soosairaj, Subramanian Mathiyazhagan, Prakasam Raja
    Current Science, 2016
  • Phytochemical screening and GC-MS analysis on Spermacoce articularis L.F. (Rubiaceae)
    International Journal of Chemtech Research, 2013

RECENT SCHOLAR PUBLICATIONS

  • Anatomical and Micromorphological Features of an Endemic Geophyte Iphigenia mysorensis (Colchicaceae)
    SSRA L.J.P. Arulanandam, P. Raja
    National Academy Science Letters 2026, 1-3 , 2026
    2026
  • Comprehensive analysis of Crotalaria willdenowiana DC.: GC-MS profiling, antioxidant and anticancer activities, molecular docking studies, and insilico ADME profiling
    PMPJ M. Sathish, R. Chamundeeswari, C. Grevasan, S. Pavithra, C. Ganapathy ...
    3 Biotech 15, 243 , 2025
    2025
  • A new record of an endemic and endangered succulent Euphorbia vajravelui for the Eastern Ghats of Tamil Nadu
    LJPAP Raja
    Zoosprint 40 (5), 30-32 , 2025
    2025
  • Ilex fargesii subsp. melanotricha (Aquifoliaceae), a new addition to the flora of India
    PRSNB N. Dhatchanamoorthy, K. Devanathan
    Rheedea 35 (1), 24–27 , 2025
    2025
  • Ceropegia rapinatiana (Britto & Bruyns) Bruyns – An Endemic Species at the Verge of Extinction
    P Raja, JK Tagore, K Thirumalai, P Jansirani
    National Academy of Science Letters 47 , 2024
    2024
  • GC–MS and In‑silico studies of Neer Nochi (Justicia gendarussa Burm.f.) against Estrogen Receptor Alpha (ERα)
    PJ M. Sathish, K. Surendirakumar, P. Raja
    Vegetos , 2024
    2024
  • GC–MS and In‑silico studies of Neer Nochi (Justicia gendarussa Burm.f.) against Estrogen Receptor Alpha (ERα)
    PRPJ M. Sahish, K. Surendirakumar
    Vegetos, 1-9 , 2024
    2024
  • Ceropegia rapinatiana (Britto & Bruyns) Bruyns – an endemic species at the verge of extinction
    KTPJ P. Raja, J.K. Tagore
    National Academy Science Letters 2024 , 2024
    2024
  • Synoptic account on angiosperm flora of Pudukkottai district, Tamil Nadu, India
    LJPAJKT P. Raja, S. Soosairaj
    Nelumbo 66 (1), 06–36 , 2024
    2024
  • Reinstatement of Acalypha fallax Mull. Arg. and description of A. brittoi sp. nov. based on micromorphological and molecular characters
    PRLJPA S. Soosairaj, M. Mary Nithya
    Nordic Journal 2024, e04505 , 2024
    2024
  • GC–MS and in‑silico studies of Neer Nochi (Justicia gendarussa Burm.f.) against Estrogen Receptor Alpha (ERα)
    PRPJ M. Sathish, K. Surendirakumar
    Vegetos 2024 , 2024
    2024
  • Stress of habitat fragmentation as cause for multi-species association: A case study from little Andaman Islands of India
    PJSS J.K. Tagore, P. Raja
    Indian Forester 150 (5), 458-461 , 2024
    2024
  • Chlorophytum kolliensis (Asparagaceae), a new species from the Eastern Ghats of Tamil Nadu, India
    BBND S. Soosairaj, P. Raja
    Nordic Journal of Botany 2024, e04254 , 2024
    2024
    Citations: 2
  • Characterization of carbon fluxes, stock and nutrients in the sacred forest groves and invasive vegetation stands within the human dominated landscapes of a tropical semi-arid …
    PRAR R.V. Akil Prasath, R. Mohanraj, K.R. Balaramdas, A.J.K. Tagore
    Scientific Reports 14, 4513 , 2024
    2024
    Citations: 8
  • Enumeration of Angiosperm diversity in Madaiyakaruppar sacred grove of Tamil Nadu, India
    ANSSA P. Raja, M. Sathish, M. Arumugam
    Indian Forester 149 (11), 1147-1154. , 2023
    2023
  • A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India
    KAAK P. Raja, L. John Peter Aulanandam, S. Soosairaj
    Adansonia 45 (19), 285-291 , 2023
    2023
    Citations: 5
  • The Genus Ophioglossum (Ophiglossaceae) in Pudukkottai District, Tamil Nadu, India
    MAPV P. Raja, M. Soniya, S. Soosairaj, M. Sathish
    Journal of Economic and Taxonomic Botany 47 (1), 22-29 , 2023
    2023
    Citations: 2
  • Theriophonum blumei (Araceae), a new species from Tamil Nadu, India
    LJP Arulanandam, S Soosairaj, P Raja, B Balaguru
    Nordic Journal of Botany 2023 (2), e03612 , 2023
    2023
    Citations: 2
  • Status assessment of the two Acanthaceae species strictly endemic to Saddle Peak National Park of Andaman and Nicobar Islands, India
    PJ J.K. Tagore, P. Raja, S. Soosairaj, MV. Ramana
    Species 24, e68s1572 , 2023
    2023
  • Dipcadi krishnadevarayae B.R.P. Rao (Asparagaceae): A new distributional record of an endemic geophyte to Tamil Nadu, India.
    SSJKT P. Raja, L.J.P. Arulanandam
    Species 24, e66s1569 , 2023
    2023

MOST CITED SCHOLAR PUBLICATIONS

  • Green synthesis of copper bionanoparticles to control the bacterial leaf blight disease of rice
    A Kala, S Soosairaj, S Mathiyazhagan, P Raja
    Current Science, 2011-2014 , 2016
    2016
    Citations: 37
  • Isolation and Identification of Xanthomonas oryzae pv. oryzae the causal agent of rice bacterial leaf blight and its activities against of six medicinal plants
    A Kala, S Mathiyazhagan
    Asian Journal of Plant Science & Research , 2011
    2011
    Citations: 24
  • Survey of Macroscopic Fungi from a Few Districts of Tamil Nadu
    AKANDPKRAJ S. SOOSAIRAJ, P. RAJA
    The Bioscan 7 (4), 669-671 , 2012
    2012
    Citations: 16
  • Characterization of carbon fluxes, stock and nutrients in the sacred forest groves and invasive vegetation stands within the human dominated landscapes of a tropical semi-arid …
    PRAR R.V. Akil Prasath, R. Mohanraj, K.R. Balaramdas, A.J.K. Tagore
    Scientific Reports 14, 4513 , 2024
    2024
    Citations: 8
  • Floristic composition of aquatic angiosperms in different wetlands of Pudukkottai district of Tamil Nadu, India
    NDJKT P. Raja, S. Soosairaj
    Asian Journal of Plant Science and Research 5 (12), 6 - 12 , 2015
    2015
    Citations: 7
  • Reproductive biology and seed germination of tropical evergreen tree Canarium strictum Roxb
    A Kala, P Raja, S Soosairaj, B Balaguru
    Journal of Biodiversity and Environmental Sciences 5 (6), 24-32 , 2014
    2014
    Citations: 7
  • Extended distribution of Capparis shevaroyensis sund-ragh (capparaceae) an endemic and vulnerable shrub in peninsular India to southern eastern ghats of tamilnaidu
    P Raja, ND Moorthy, A Kala, S Soosai Raj
    Ind J Fund Appl Life Sci 3 (1), 137-140 , 2013
    2013
    Citations: 6
  • A new species of Justicia L. (Acanthaceae) from Tamil Nadu, India
    KAAK P. Raja, L. John Peter Aulanandam, S. Soosairaj
    Adansonia 45 (19), 285-291 , 2023
    2023
    Citations: 5
  • New distribution record of two endemic plant species, Euphorbia kadapensis Sarojin. & RRV Raju (Euphorbiaceae) and Lepidagathis keralensis Madhus. & NP Singh (Acanthaceae), for …
    P Raja, N Dhatchanamoorthy, S Soosairaj, P Jansirani
    Journal of Threatened Taxa 12 (14), 17045-17048 , 2020
    2020
    Citations: 5
  • Spilanthes radicans Jacq.(Asteraceae) a new record to Tamilnadu, India.
    P Raja, N Dhathchanamoorthy, A Kala, S Soosairaj
    International Journal of Integrative Sciences, Innovation and Technology … , 2013
    2013
    Citations: 5
  • Phytochemical screening and GC-MS analysis on spermacoce articularis Lf (Rubiaceae)
    S Soosairaj, A Kala, P Raja, K Vijaya
    International Journal of Chem Tech Research 5 (6), 3070-3074 , 2013
    2013
    Citations: 5
  • Lepidagathis decumbens N. Dhatchan. & S. Soosairaj, sp. nov. (Acanthaceae), a new species from Tamil Nadu, India
    SSBN Dhatchanamoorthy N., Karthikeyan C., Raja P.
    Adansonia, sér. 3 44 (24), 321-329 , 2022
    2022
    Citations: 4
  • Two additions to the flora of the Palni Hills, southern India
    BBTD S.Soosairaj, P. Raja
    Journal of Threatened Taxa 8 (9), 9216-9220 , 2016
    2016
    Citations: 4
  • Jasminum greenii sp. nov.(Oleaceae): A new species from Tamil Nadu, India
    P Raja, JK Tagore, S Soosairaj, N Dhatchanamoorthy
    Indian J. Forest 148 (1), 107-108 , 2022
    2022
    Citations: 3
  • Derris gamblei sp. nov. (Fabaceae) from Tamil Nadu, India
    P Raja, S Soosairaj, N Dhatchanamoorthy, JK Tagore
    Nordic Journal of Botany 35 (4), 423-425 , 2017
    2017
    Citations: 3
  • MICROMORPHOLOGICAL ASSESSMENT AND STEM ANATOMY OF SPERMACOCE SPECIES OF TAMILNADU, INDIA
    A KALA, S SOOSAIRAJ, N RAJA, P. AND DHATCHANAMOORTHY
    Life Sciences Leaflets 8, 19-28 , 2013
    2013
    Citations: 3
  • Chlorophytum kolliensis (Asparagaceae), a new species from the Eastern Ghats of Tamil Nadu, India
    BBND S. Soosairaj, P. Raja
    Nordic Journal of Botany 2024, e04254 , 2024
    2024
    Citations: 2
  • The Genus Ophioglossum (Ophiglossaceae) in Pudukkottai District, Tamil Nadu, India
    MAPV P. Raja, M. Soniya, S. Soosairaj, M. Sathish
    Journal of Economic and Taxonomic Botany 47 (1), 22-29 , 2023
    2023
    Citations: 2
  • Theriophonum blumei (Araceae), a new species from Tamil Nadu, India
    LJP Arulanandam, S Soosairaj, P Raja, B Balaguru
    Nordic Journal of Botany 2023 (2), e03612 , 2023
    2023
    Citations: 2
  • Solanum pulneyensis Soosairaj, sp. nov. (Solanaceae) from Palani Hills National Park of Tamil Nadu, India
    BBJKT S. Soosairaj, P. Raja
    Adansonia 43 (21), 235-240 , 2021
    2021
    Citations: 2