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Open Access
Wood property profile of rosewood (dalbergia latifolia roxb.) ceylon rosewood (albizia odoratissima (Linn.F) Benth.) and raintree(Samanea saman (jacq.) Merr.)
(Department of Tree Physiology and Breeding,College of forestry, Vellanikkara, 2005) Vinay Kumar, Sahu; KAU; Gopakumar, S
In the state of Kerala, heartwoods of lesser known timber species viz., Albizia odoratissima (Ceylon rosewood) and Samanea saman (rain tree) are allegedly being used as “substitutes” and “adulterants” for making furniture of Dalbergia. latifolia (Indian rosewood) mainly due to their similar wood colour. As this spurious practice has serious implication in timber trade, a study was undertaken to profile the selected wood properties of all these three species to highlight their similarities and differences. The study involved analyzing selected physical, mechanical, anatomical and biochemical properties of A. odoratissima and S. saman and comparing it with the wood properties of D. latifolia as available from relevant literatures. Variations of higher magnitude were noted between the three species for some wood properties, and with respect to few other properties, the differences were lesser. Significant variations were also observed between tissue types viz., sapwood and heartwood for some wood properties. Heartwood tissue types of S. saman and D. latifolia displayed high calorific value, where as, for A. odoratissima both tissue types (sapwood and heartwood) exhibited medium calorific value. The physical properties of the heartwood of A. odoratissima were observed to be higher than that of D. latifolia. S. saman possessed lower values for the physical properties as compared to D. latifolia. Basic specific gravity, radial and volumetric shrinkages (green to oven dry) were considerably different for all the three species. Generally, for both Ceylon rosewood and rain tree tangential shrinkage was higher than radial shrinkage for both the tissue types. Mechanical properties of A. odoratissima were superior to D. latifolia and S. saman, except modulus of elasticity in compression parallel to grain. On the other hand mechanical properties of S. saman were closer to D. latifolia. Measure of fibre stress at limit of proportionality and modulus of elasticity in static bending and modulus of elasticity in compression parallel to grain are considerably different for the three species. In A. odoratissima and S. saman, the mechanical properties of sapwoods varied non significantly with the strength properties of heartwoods. S. saman exhibited superior strength properties for heartwood over its sapwood. Vessel diameter, distribution of parenchyma and ray height can be used to differentiate the three species. In all the species, along the radial axis from pith towards periphery, the vessel diameter, ray height, ray width increased along the region of heart wood. Likewise, ray frequency, and vessel frequency decreased along radial axis in heartwood region. Average vessel diameter, ray height and ray width of sapwoods were greater than that of the heartwoods. Lignin, cellulose and holocellulose percent of A. odoratissima and S. saman were significantly greater than D. latifolia. Higher lignin, cellulose and holocellulose content are responsible for the higher strength properties of A. odoratissima. Methanol-acetone extracts of heartwood of D. latifolia exhibits specific peak wavelengths under spectrometric analysis, which are not found in the other two species. Phenolic compounds were observed to influence some of the physical properties.
Open Access
Morphological and anatomical properties of teak seedlings as influenced by nursery techniques
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 2004) Girija Pushpom, R P; KAU; Anoop, E V
An experiment was carried out at College of Forestry, Kerala Agricultural University, Vellanikkara with the objective to evaluate the best nutrient levels and sowing treatments required for the production of good quality stumps based on anatomical properties of the seedlings with particular reference to wood formation due to cambial activity. The different nutrient and sowing methods were randomly allocated following completely randomized design. From the experiment, it was found that the best nutrient and sowing method combinations were N2S3 (cowdung 0.4 kg/rrr' and neem cake 0.2 kg/rn ' with spacing of 12 cm x 12 cm between seeds). In terms of biometric characters and biomass characteristics of seedlings it was also found that in quick growing seedlings, vessel diameter was large and vessel frequency was less. Collar girth was positively related with ring width and negative related with vessel frequency. Comparing the performance of nursery raised seedlings with root trainer raised seedlings it was found that the growth characteristics as well as the anatomical properties were inferior for root trainer raised seedlings. In the present study it was found that the best quality teak stumps could be produced by intensive cultural practices. Intensive management of nursery seedlings could produce VlgOurOUS seedlings and thereby it could produce good quality stumps in less time. Results of the present study showed that traditional system of production of teak stumps were efficient By imposing superior nutrient and sowing methods good quality, vigorous stumps can be produced to meet the immediate plantation requirements within a short period.
Open Access
Diversity of small mammals in the Parambikulam wildlife sanctury
(Department of Wild Life Sciences, College of Forestry, Vellanikkara, 2003) Lekshmi, R; KAU; Ambika Varma, B
A detailed study was conducted in the Parambikulam Wildlife Sanctuary during 1999-200 I to prepare an inventory and to estimate the abundance of small mammal fauna in diverse ecological habitats of the Parambikulam Wildlife Sanctuary. In this study, a total of twenty seven species of small mammals belonging to eight orders were recorded from the Parambikulam Wildlife Sanctuary. Among the eight orders Rodentia was represented maximum with eleven species followed by Carnivora with ten species, remaining orders represented only by a single species. While comparing the rodents trapped from different habitats, natural forest account for more number of species than plantation and vayal. The most common rodent species in the three habitats was Rattus rattus, whereas Golunda ellioti (Indian bush rat) was found only in the moist deciduous natural forest because of the favourable ecological conditions prevailing there. Maximum diversity was more in the natural forest than in plantation and vayal whereas species richness was more in vayal followed by plantation and natural forest. The relative dominance was also high in natural forest than plantation and vayal. Correlation between floral diversity and rodent species indicates that natural forest with more number of plant species possessed high rodent species richness. The ideal conditions prevailing in the natural forest would have helped the survival of rodent species. The lack of ideal conditions in the plantation and vayal would have been the reason for lesser number of rodent species.
Open Access
Evaluation of seed source variation and clonal propagation techniqes in Jatropha curcas linn.
(Department of Tree Physiology and Forestry, College of Forestry, Vellanikkara, 2007) Anisha Kalkoor, M; KAU; Vijayakumar, N K
A study was conducted in College of Forestry, Vellanikkara, Trichur, during the period 2005-2007 to evaluate different seed sources Jatropha curcas, a potential source of producing biodiesel for their genetic variation and to standardize efficient clonal propagation techniques. The study involved the evaluation of seed sources for their seed and seedling parameters as well as field performance of the plants. Attempts were made to standardize of macro and micro propagation techniques for the multiplication of elite genotypes. The material used for the evaluation consisted of different seed sources from various parts of Kerala and Karnataka. Although the variation among the seed sources for most of the seedling characters in the nursery was found non significant, a considerable variation was observed among them in their field performance. Considerable variation was also noticed for the seed parameters such as length, width, 100 seed weight, germination percentage, kernel: seed weight ratio and seed oil content. None of the seed sources excelled for all the characters studied. Among the different seed sources three seed sources viz., Kasargod, KAU and Palakkad seed sources were found to be superior in terms of most of the characters studied. Standardization of rooting of cuttings was attempted with 10 and 20 cm cuttings taken from semi-hardwood and softwood parts of the stem. Three levels each of IAA, IBA and NAA were used for evaluating their efficiency for rooting as well as shoot formation in the stem cuttings. Effect of these hormones on the shoot parameter was found less significant. However, highest sprouting was recorded in IAA 100 ppm where as IAA 250 ppm recorded highest number of shoots. Almost all the root characters were found to be greatly influenced by growth hormones. The semi-hardwood cuttings were found superior to the soft wood cuttings while, the 20 cm cuttings were found better than 10 cm cuttings with respect to most of the characters studied. Clonal propagation of Jatropha curcas was attempted by micro propagation through tissue culture using nodal segments as explants. Among the three basal media tried viz., MS, WPM and B5 medium, MS was found to be better in terms of bud, leaf and shoot initiation. The culture establishment was greatly influenced by the season of culturing. All explants cultured during the rainy season were got contaminated. A fungicidal dip in 0.2 per cent Bavistin (Carbendazim) and Indofil M- 45 (Mancozeb) for 1 hour followed by 15 minute dip in 0.1 per cent HgCl2 was the most effective surface sterilization procedure. Murashige and Skoog medium supplemented with 1.0 mg l-1 kin was found to be the best medium for shoot production. Highest average number of leaves (3.47), maximum number of leaves (8.67) and maximum shoot length was observed in this medium. The synergistic effect of BA and kin in MS medium was found to be better than supplementing them individually especially for the enhanced release of axillary buds. The treatment MS+0.5 mg l-1BA+1.0 mg l-1 kin was found to be the best treatment combination to get highest shoot initiation.
Open Access
Zonation,leaf phenology and litter dynamics of mangrove forest at Puduvyppu
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 2003) Ajay Dattaram, Rane; KAU; Asokan, P K
As species distribution along the sea-land interface to the land interior IS attributed to gradients in soil electro-chemical properties and tidal frequency and nutrient cycling in a system is dependent on litterfall and decay dynamics. Hence, the study for estimating zonation pattern and regeneration status of species along the ocean-land interior trans~cts, along with litter dynamics (literfall and litter decay) was carried out at Puduvyppu mangrove forest. Zonation pattern of species was revealed by carrying out phytosociological analysis along the land-ocean transect and correlating with gradients in electro-chernical properties of soil. Litterfall was studied by evaluating interzonal and monthly variations in litterfall between species for one year. Leaf fall and production was inturn correlated with weather parameters. Decay dynamics was studied by involving six predominant species of the forest namely, Avicennia officinalis, Bruguiera cylindrica, Rhizophora mucronata, Sonneratia caseolaris, Acanthus ilicifolius and Excoecaria agallocha and by estimating interzonal and monthly variations in mass loss and nutrient concentrations of decomposing leaf samples for 12 months. Results show that the area can be divided into three zones (zone I: 0-300 m, zone U: 301-800 m, zone Ill: 801-1200 m from the sea) based on species distribution pattern. Species diversity along the zones decreased from zone I to zone I I, whereas, phytosociological para~1eters of species increased. It was also observed that species like R. mucronata and S. caseolaris were restricted in zone I, whereas, A. officinalis and B. cylindrica were abundant towards the landward side, due to the tidal sorting of the species. Electrical conductivity and soil nutrient (N, K, Na) concentrations increased towards the landward side, whereas, pH decreased. Furthermore, soil P concentrations and in situ redox potential positively affected stand density and E. agallocha stand density respectively. Regeneration was profuse in the central zone of the forest (700-800 111 from the sea) and decreased towards the landward side and the seaward side, implying that monospecifity and tidal inundation affected regeneration. Among the species, A. officinalis seedlings were abundant in the lower height class «50 cm) and B. cvlindrica in upper height class (>50 cm), implying that shade tolerance of the species decided its establishment potential. Litterfall did not vary among the zones suggesting that the dominant A. officinalis determined litterfall of the forest. Leaf fall peaked during winter season (November-December), whereas, leaf production was initiated by rainfall, implying that rainfall and temperature controlled phenological cycles in species. Mass loss followed an exponential pattern in A. ilicifolius, A. officinalis. E. agallocha and S. caseolaris, whereas, it followed a linear pattern in B. cylindrica and R. mucronata. Similarly decay rates were inversely related with initial lignin and lignin: nitrogen ratio of the decomposing leaves. And also, interzonal variations in decay rates were observed, implying that site and species affected decay rates. Nutrient concentrations decreased with Nand K concentrations decreasing and P moderately increasing in the litter bags during the course of decomposition, implying that tidal frequency and mineralization-immobilization frequencies decided nutrient release patterns in these species. In general this is a low diversified, juvenile with an efficient nutrient input-out put mechanism.
Open Access
Effect of seed treatments and shade on seedling growth dynamics of pongamia pinnata (Linn.) pierre in the nursery
(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2009) Gururaj Sankeshwar, B; KAU; Gopakumar, S
The present study entitled “Effect of seed treatments and shade on seedling growth dynamics of Pongamia pinnata (Linn.) Pierre in the nursery” was carried out in College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur during the period of 2007-2009. In the first phase, seeds were subjected to six pre-sowing treatments. GA3 treated seeds recorded highest Germination percentage, Final Mean Daily Germination (FMDG), Germination Value (GV) and Peak Value (PV). The effect of seed treatments were observed on various biometric parameters like height, collar diameter, number of leaves and primary branch. GA3 treated seeds recorded better height and collar diameter during the initial stage of seedling growth. At the end of study cold water seed treatment was found to be effective in enhancing seedling growth. However, none of the pretreatments was observed to cast a significant effect on biomass production and root growth parameters in Pongamia pinnata seedlings. In the second phase, to evaluate seedling growth under different shade conditions, seedlings were placed under 25 per cent shade, 50 per cent shade, 75 per cent shade and full sunlight situations. Shade treatments did not significantly influence height and collar diameter growth of Pongamia pinnata seedlings in the nursery. The maximum leaf production and primary branch production was observed in seedlings kept under full sunlight and 50 per cent shade respectively. Under seventy five per cent shade seedlings produce maximum shoot and root dry weight. The shoot: root ratio and total biomass was also maximum for seedlings kept under 75 per cent shade. Root length and spread were maximum under 50 per cent shade. However, shade did not significantly effect secondary root production. Shade levels also did not influence Pongamia pinnata seedlings with respect to relative growth rate and leaf area. However, Specific leaf area and Leaf area ratio was higher under 25 per cent shade. Highest Specific leaf weight was observed for seedlings under full sunlight. Shade had no significant effect on leaf weight ratio of seedlings. Maximum stomatal number was recorded under 25 per cent shade. In the nursery stage shade is casting an overriding influence with regards to various growth parameters of Pongamia pinnata.
Open Access
Effect of elevated CO2 concentration on growth and physiology of selected tropical tree seedlings
(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2010) Neenu Somaraj; Gopakumar, S
The present study entitled “Effect of elevated CO2 concentration on growth and physiology of selected tropical tree seedlings.” was carried out in College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur during the period 2008-2010. There are references that elevated CO2 typically increases tree seedling growth and has also modified physiological processes. Polybag seedlings of five economically important tree species were exposed to 500-550 ppm CO2 concentration and another similar set of plants were raised under ambient atmospheric CO2 condition (370-380 ppm). The growth rates and physiology were observed for eight months. Tree seedlings under elevated CO2 concentration put in more height and collar diameter than the seedlings under atmospheric CO2.A higher leaf production and larger leaf area was recorded in seedlings under elevated CO2 concentration. The different levels of CO2 also showed significant effects on the total dry matter content. However, interactions between two CO2 levels and five tree seedlings had no significant impact on the shoot: root ratios throughout the study period. The different CO2 treatment did not significantly affect the relative growth rate (RGR), net assimilation rate (NAR), specific leaf area (SLA) and the leaf area ratio (LAR) of seedlings. However, both CO2 levels showed significantly different impact on the leaf weight ratio (LWR) of seedlings. Seedlings under elevated CO2 recorded lowest number of stomata compared to seedlings under atmospheric CO2 concentration. The varying CO2 concentrations showed significant effect on the rate of photosynthesis of the tree seedlings. Chlorophyll a and Chlorophyll b in tree seedlings was not significantly influenced under different CO2 concentrations. However, total chlorophyll content showed significant influence. Seedlings under elevated CO2 recorded lowest soluble protein content compared to seedlings under atmospheric CO2 concentration. Hence, CO2 enrichment technique can be used as an economically viable nursery technology for production of more healthy and vigorous planting stock to meet the increasing demand for social forestry /agro forestry programme.
Open Access
Influence of host plant on the physiological attributes of field grown sandal (santalum album L.).
(Department of Tree Physiology and Breeding,College of forestry, Vellanikkara, 2011) Delphy, Rocha; KAU; Ashokan, P K
Effects of host plant, casuarina on the carbon assimilation, water and nutrient absorption in field grown sandalwood was studied at College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur during the year 2009-2011. Radioisotopic study to understand the trans-haustorial translocation from the host to field grown sandalwood tree and anatomical studies of sandalwood haustoria were also taken up during the investigation. The investigations were carried out in a six year old sandal-field, where sandalwood tree with and without host were established as a part of an earlier research project. The experiment was laid out with single tree plants, in RBD with three treatments viz, T1 - Sandalwood tree without host (Casuarina) (Host plant dead naturally within 2 years after establishment of sandal), T2 - Sandalwood tree with host (Casuarina), T3 - Sandalwood tree with host (Casuarina) and the host plant cut and removed at six year stage of growth. The host plant casuarina did not influence the height and diameter (dbh) of the sandalwood tree significantly during its six years growth. Sandalwood trees growing with host showed higher rate of photosynthesis (carbon assimilation) than sandalwood trees growing without host. Sandalwood tree growing without specific host can extend its root for finding a host in its vicinity, and forming haustorial connections, for meeting its water and nutrient requirements. Sandalwood trees grown with host showed higher plant water potential than sandalwood trees grown without host. Plant water potential has decreased significantly after the removal of host plant from the sandalwood pit. It also resulted in leaf wilting and leaf fall in sandalwood tree, indicating the contribution of the host in maintaining higher water potential in sandalwood trees. Sandalwood trees growing with host showed higher leaf N, P and K content. The N, P and K content of the sandalwood tree leaf decreased considerably after the removal of the host plant. The removal of host did not show any significant effect on leaf micronutrient content of sandalwood tree. Sandalwood growing without host also formed haustoria with roots of host plants growing in the adjacent pit. The sandalwood growing with host in the same pit showed higher number of haustoria. Total number of haustoria was higher on the primary root of the host followed by secondary and tertiary roots. Size of the haustorium, the depth of the penetration, the length of the penetration peg and area of coverage of endophyte was higher in the case of secondary root haustoria than in tertiary. Anatomical study of sandalwood haustoria showed that elongated parenchyma cells of the haustorium projected towards the host root xylem, making vascular connection between sandalwood tree root and the host plant root. Radioactive phosphorus (32P) labelling on host plant, casuarina and tracing in sandalwood tree and other hosts revealed that there is inter-translocation of nutrients between sandalwood and host plants, sandalwood and sandalwood, host and host. The data indicated that a network of roots of sandalwood tree and the hosts are formed through haustorial connection resulting in xylem-translocation. Peak count of 32P was obtained on the eighth day of its application. Radiotracer studies on different sandalwood tree-host associations showed that association of sandalwood and cocoa as host was efficient in haustorial translocation of 32P. Labelling of wild grasses growing around sandalwood tree with 32P revealed that, sandalwood also depends on wild grass for meeting its nutrient requirements.
Open Access
Floristic and edaphic attributes of three land use systems in Wayanad, Kerala
(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2011) Aneesh, K S; KAU; Gopakumar, S
The present study was conducted in Thollayiram area of South Wayanad Forest Division of Wayanad district. The objective of the study is to compare the various floristic and edaphic attributes of three land use systems, viz an ecologically fragile land (EFL), a section 5 land (as per section 5 of Kerala Preservation of Trees Act (1986) and vested forest found in South Wayanad Forest Division. A total area of one hectare was surveyed in each of the three land use systems. The floristic study revealed that species richness of these land use systems were 40, 26 and 32 respectively. The major associations of trees in the ecologically fragile land were Melicope lunu-ankenda- Litsea oleoides- Litsea wightiana and Diospyros nilagirica. In section 5 land, the major associations are Litsea wightiana- Dillenia bracteata and Diospyros nilagirica whereas the vested forest is dominated with Palaquium ellipticum, Myristica beddomei, Dimocarpus longan and Mesua ferrea. Total basal area of vested forest is 44.56 m2 followed by ecologically fragile land (37.47 m2) and section 5 land (33.60 m2). By comparing the Shannon –wiener index of these land use system, vested forest recorded the highest value (2.96) followed by ecologically fragile land (2.93) and section 5 land (2.80) whereas Simpson indices are 0.93, 0.91 and 0.92 respectively. Regarding vegetation structure, a typical three storeys was noticed for ecologically fragile land and vested forest but section 5 land has only two storeys. Texture analysis revealed that soil texture of these land use systems are sandy loam. The pH values of the soil ranges from 3.84 to 4.79. The higher value of bulk density was recorded for section 5 land (1.46 g cm-3) followed by ecologically fragile land (1.34 g cm-3) and vested forest (0.88 g cm-3). There is no significant difference in the values of organic carbon and available potassium across three land use systems whereas available phosphorous was significantly higher in vested forest. The information regarding diversity of ecologically fragile land in Thollayiram will be helpful to the state forest department in designing better strategies for the long term conservation of this ecosystem.

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