Kerala Forest Research Institute

IN Kerala, India

Kerala Forest Research Institute

IN Kerala, India
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Jithin K.V.,Kerala Forest Research Institute | Jose P.A.,Kerala Forest Research Institute
Nordic Journal of Botany | Year: 2017

Lepidagathis benojiana, a new species of Lepidagathis, collected from the Idukki district, Kerala, southern Western Ghats, India is described along with photographs. The new species is closely allied to L. chlorostachya Nees. but differs from the latter in its height, length of petiole, position and number of spikes, length of peduncle, length of floral whorls, colour of flower, colour and nature of stamens, nature of fruit and shape of the seed. © 2017 Nordic Society Oikos.

Sajitha K.L.,Kerala Forest Research Institute | Florence E.J.M.,Kerala Forest Research Institute
Journal of Tropical Forest Science | Year: 2013

An actinomycete isolated from the soil, identified as Streptomyces sp. SA18, was found to be an effective antagonist against the fungus Lasiodiplodia theobromae that caused sapstain on rubberwood. One of the antagonistic factors responsible for this inhibitory effect was identified as chitinase enzyme production, which degraded the chitin of fungal cell wall to N-acetyl D-glucosamine. In the chitin agar plate inoculated with Streptomyces sp. SA18, the dye bound with stable chitin and fluoresced under ultra violet light. On the contrary, chitin-free portions appeared dark indicating degradation of chitin by chitinase enzyme produced by Streptomyces sp. SA18. © Forest Research Institute Malaysia.

Jayakumar R.,University of Delhi | Nair K.K.N.,Kerala Forest Research Institute
Tropical Ecology | Year: 2012

The paper aims to evaluate the beta diversity in homogeneous and heterogeneous habitats in tropical forests. Also, the relationship between beta diversity and richness in the rain forests and monsoon forests is elucidated. The study was conducted in a forest landscape of Nilgiri Biosphere Reserve in the Western Ghats of India. The Wilson and Shmida index was used to assess the beta diversity of the angiosperms of the region. Results showed that species richness and beta diversity varied in different vegetation types; in heterogeneous habitats, species turnover was mainly due to habitat restriction, and not dispersal limitation, whereas within a homogeneous habitat beta diversity was dependent on dispersal limitation. Most of the species were restricted to specific habitats; a few species were more adapted to a wide spectrum of climatic conditions. Beta diversity and species richness of rain forests were higher than those of the monsoon forests. © International Society for Tropical Ecology.

Kallarackal J.,University of Bayreuth | Kallarackal J.,Kerala Forest Research Institute | Bauer S.N.,University of Bayreuth | Nowak H.,University of Bayreuth | And 2 more authors.
Planta | Year: 2012

Reports about diurnal changes of assimilates in phloem sap are controversial. We determined the diurnal changes of sucrose and amino acid concentrations and fluxes in exudates from cut aphid stylets on tansy leaves (Tanacetum vulgare), and sucrose, amino acid and K+ concentrations and fluxes in bleeding sap of castor bean pedicel (Ricinus communis). Approximately half of the tansy sieve tubes exhibited a diurnal cycle of sucrose concentrations and fluxes in phloem sap. Data from many tansy plants indicated an increased sucrose flux in the phloem during daytime in case of low N-nutrition, not at high N-nutrition. The sucrose concentration in phloem sap of young Ricinus plants changed marginally between day and night, whereas the sucrose flux increased 1.5-fold during daytime (but not in old Ricinus plants). The amino acid concentrations and fluxes in tansy sieve tubes exhibited a similar diurnal cycle as the sucrose concentrations and fluxes, including their dependence on N-nutrition. The amino acid fluxes, but not the concentrations, in phloem sap of Ricinus were higher at daytime. The sucrose/amino acid ratio showed no diurnal cycle neither in tansy nor in Ricinus. The K+-concentrations in phloem sap of Ricinus, but not the K+ fluxes, decreased slightly during daytime and the sucrose/K+-ratio increased. In conclusion, a diurnal cycle was observed in sucrose, amino acid and K+ fluxes, but not necessarily in concentrations of these assimilates. Because of the large variations between different sieve tubes and different plants, the nutrient delivery to sink tissues is not homeostatic over time. © 2012 Springer-Verlag.

Pillai T.G.,Jawaharlal Nehru Cancer Hospital and Research Center | Pillai T.G.,Kerala Forest Research Institute | Uma Devi P.,Pathirissery Mana
Mutation Research - Genetic Toxicology and Environmental Mutagenesis | Year: 2013

The in vivo radioprotective effect of a beta-glucan (BG) isolated from the mushroom Ganoderma lucidum, against radiation (RT) induced damage was investigated taking mouse survival, hematology, liver GSH (Reduced glutathione), liver Malondialdehyde (MDA) and bone marrow chromosomal aberrations as end points. Young adult swiss albino mice were whole body exposed to gamma radiation. For mouse survival study, BG was administered orally (250. μg/kg body wt or 500. μg/kg body wt) 15. min before or 5. min after 8. Gy exposure. For other parameters BG was given orally 5. min after 4. Gy exposure. The radioprotective effect of BG was compared with that of clinically used radioprotective drug amifostine (WR-2721), at 300. mg/kg body wt administered intraperitoneally, 30. min before irradiation. BG (500. μg/kg body wt) produced (66%) mouse survival at 30 days given post irradiation, and 83% survived at 30 days with 300. mg/kg body wt of amifostine administered before RT while RT alone produced 100% mortality. BG is not toxic at the radioprotective dose. Significant reduction in number of aberrant cells and different types of aberration was observed in both BG and amifostine administered groups compared to radiation alone treated group. BG seems to have potential for use in protection against unplanned radiation exposures. © 2012 Elsevier B.V.

Sajitha K.L.,Kerala Forest Research Institute | Maria Florence E.J.,Kerala Forest Research Institute | Dev S.A.,Kerala Forest Research Institute
Research in Microbiology | Year: 2014

Diverse bacterial biocontrol agents from various sources of aerobic composts against the sapstain fungus Lasiodiplodia theobromae in rubberwood (. Hevea brasiliensis) were isolated, screened and identified by various morphological, biochemical and molecular techniques. The inhibitory effect of seventeen bacterial isolates was examined and seven exhibited inhibition towards the sapstain fungus. Among the seven antagonists, six were conclusively identified as Bacillus subtilis and one as Paenibacillus polymyxa using 16S rRNA-encoding gene sequencing. This is the first report on the occurrence of P. polymyxa, a potent biofertilizer and antagonist in vermicompost. HiCrome Bacillus agar was identified as an effective medium for differentiation of B. subtilis from other Bacillus species. The present work demonstrates the efficacy of the antagonistic property of B. subtilis strains against rubberwood sapstain fungus. Culture-based antagonistic inhibition displayed by B. subtilis can be extended to cater to the biocontrol requirements of wood-based industries against the stain fungus. The study showed the utility of an integrated approach, employing morphological, biochemical and molecular tools for conclusive identification of several bacterial isolates present in aerobic composts from diverse sources. © 2014 Institut Pasteur.

Kumara H.N.,Salim Ali Center for Ornithology and Natural History | Suganthasakthivel R.,Kerala Forest Research Institute
Tropical Conservation Science | Year: 2011

Petinomys fuscocapillus, Jerdon 1847,Travancore flying squirrel, is known to occur in the forests of India and Sri Lanka. In spite of extensive surveys very few individuals were recorded in the last century. For a better understanding of the possible range of distribution, the present study mapped the potential geographic distribution of the P. fuscocapillus from peninsular India and Sri Lanka. We utilized occurrence records of 32 confirmed sightings of P. fuscocapillus to model the species ́potential geographic distribution by applying an ecological niche modelling (ENM) framework using Genetic Algorithm for Rule set Prediction (GARP). Results indicate that the modeled potential distribution of P. fuscocapillus in India is highly restricted to the narrow strip on western slope of the Western Ghats, and in Sri Lanka the predicted distribution is predominant in the lowlands of wet and intermediate zones. Further, about 88% of the modeled potential distribution range lies outside the protected area network and occupies lowland evergreen, semi-evergreen and its degraded forested stages. The narrow environmental niche of both known and modeled potential distribution and highly susceptible forests with less protection raise the need for conservation efforts and future studies. © Honnavalli Nagaraj Kumara and Ramamoorthy Suganthasakthivel.

Kallarackal J.,Kerala Forest Research Institute | Roby T.J.,Kerala Forest Research Institute
Biodiversity and Conservation | Year: 2012

The enhancement in photosynthesis at elevated concentration of carbon dioxide level than the ambient level existing in the atmosphere is widely known. However, many of the earlier studies were based on instantaneous responses of plants grown in pots. The availability of field chambers for growing trees, and long-term exposure studies of tree species to elevated carbon dioxide, has changed much of our views on carbon dioxide acting as a fertiliser. Several tree species showed acclimation or even down-regulation of photosynthetic responses while a few of them showed higher photosynthesis and better growth responses. Whether elevated levels of carbon dioxide can serve as a fertilizer in a changed climate scenario still remains an unresolved question. Forest-Air-Carbon dioxide-Enrichment (FACE) sites monitored at several locations have shown lately, that the acclimation or down regulation as reported in chamber studies is not as wide-spread as originally thought. FACE studies predict that there could be an increase of 23-28% productivity of trees at least till 2050. However, the increase in global temperature could also lead to increased respiration, and limitation of minerals in the soil could lead to reduced responses in growth. Elevated carbon dioxide induces partial closure of leaf stomata, which could lead to reduced transpiration and more economical use of water by the trees. Even if the carbon dioxide acts as a fertilizer, the responses are more pronounced only in young trees. And if there are variations in species responses to growth due to elevated carbon dioxide, only some species are going to dominate the natural vegetation. This will have serious implications on the biodiversity and the structure of the ecosystems. This paper reviews the research done on trees using elevated CO 2 and tries to draw conclusions based on different methods used for the study. It also discusses the possible functional variations in some tree species due to climate change. © 2012 Springer Science+Business Media B.V.

Sreekanth P.M.,Bangalore City College New Campus | Balasundaran M.,Tropical Institute of Ecological science | Nazeem P.A.,Kerala Agricultural University | Suma T.B.,Kerala Forest Research Institute
Conservation Genetics | Year: 2012

Teak (Tectona grandis L. f.) is one of the most durable timbers in the world that is used for all conceivable purposes. Its widespread use has constrained the distribution of species to small and isolated populations. The genetic structure within and between nine natural teak growing forests of the Western Ghats of India belonging to the states of Kerala, Karnataka and Tamil Nadu was investigated using amplified fragment length polymorphism markers to provide reasoned scientific management practices and conservation measures. The use of ten selective primer combinations on 180 samples (9 populations X 20 trees) resulted in a total of 665 bands of which 99.4 % were polymorphic. Gene diversity index (H) varied from 0.1387 (Barchi) to 0.2449 (Wayanad). The mean gene diversity (HS) was 0.1995 and the total gene diversity (HT) was 0.264. The Southern Western Ghats populations showed higher within population gene diversity. The relative magnitude of genetic differentiation among populations (GST) was 0.244. Positive correlation between genetic and geographical distances was observed. PCoA, UPGMA and STRUCTURE analyses revealed the tendency of the individual trees within a population to align together indicating specific identity of each population. In the UPGMA dendrogram, Nilambur population joined separately with a large cluster in which the other Kerala populations and Tamil Nadu population formed sub clusters indicating a separate identity for Nilambur population among Southern Western Ghats populations. © 2012 Springer Science+Business Media B.V.

Sajitha K.L.,Kerala Forest Research Institute | Dev S.A.,Kerala Forest Research Institute
Biological Control | Year: 2016

The aesthetic value of the rubberwood is lost due to the bluish black discolouration caused by sapstain fungus, Lasiodiplodia theobromae, which leads to an economic loss in the wood industry. In our earlier study, Bacillus subtilis B1 has been identified as the potential biocontrol agent against L. theobromae, the dominant sapstain fungus infecting the rubberwood. Bacillus subtilis is known for its biocontrol activity against a wide range of fungal pathogens by various means including the action of non-ribosomal antifungal lipopeptides viz. iturin, surfactin and fengycin. The present study aims to characterize and quantify the gene expression levels of these antifungal lipopeptidic genes using RT-qPCR during inhibition process in the dual culture. Among the three lipopeptide genes, fengycin biosynthetic gene was constantly expressed in high amounts throughout the antagonism. The gene for surfactin biosynthesis was also expressed all through and may have helped in the growth and spreading of B. subtilis B1. Bacilysin biosynthetic gene expressed only in the fourth and fifth days dual culture might have complemented the action of fengycin in inhibiting the sapstain fungus. © 2016 Elsevier Inc.

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