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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
Comparative performance of three exotic tree species in social forestry strip plantation in Trichur Social Forestry Division
(College of Forestry,Vellanikkara, 1990) Nandakumar, G; KAU; KrishnanNair, V R
A study was conducted in 1987-88 on the social forestry strip plantation on the premises of the Sitaram Textile mills Ltd. In the Trichur Social Forestry Division of Kerala State; to compare the performance of three exotic fast growing tree species, Casuarina equisetifolia, Acacia auriculiformis and Eucalyptus tereticornis in social forestry strip plantation. Comparisons were made on the three year old plantation in respect of growth, biomass production and impact on the soil and undergrowth. General observations were also made on the tree form, occurance of pests and diseases and wild life habitat improvement. The site of experiment was being used for dumping coal cinders and other wastes from the textile mill and was barren before planting. The experiment was laid out in RBD with five replications. The results obtained in the study have been summarised below : At the end of the third year Acacia auriculiformis had a DBH of 4.56 cm followed by Eucalyptus tereticornis with 3.82 cm and Casuarina equisetifolia with 1.62 cm. The mean annual diameter increments were 1.44 cm/year in Acacia, 1.20 cm/year in Eucalyptus and 0.51 cm/year in Casuarina. Acacia had more primary branches (27/tree) followed by Eucalyptus (23/tree) and Casuarina (17/tree). The first primary branch was 3.18 m above the ground in Eucalyptus, 2.22 m in Acacia and in 2.16 m in Casuarina. Acacia had 100% survival at the third year while Eucalyptus had 88%. But Casuarina had only 72% survival rates. In growth as well as survival, Acacia auriculiformis was found to be the best among the three. Eucalyptus tereticornis was found superior to Casusrina equisetifolia while the latter was the least impressive of the three. The total biomass yield at the third year was 98.438 mt (drymatter)/ha in Acacia auriculiformis, 48.424 mt/ha in Eucalyptus tereticornis and 12.506 mt/ha in Casuarina equisetifolia. Acacia had a mean annual biomass increment of 32.813 mt/ha. MAI of Eucalyptus was 16.141 mt/ha while that of Casuarina was only 4.169 mt/ha. In biomass production too, Acacia auriculiformis was found superior to Eucalyptus tereticornis and Casuarina equisetifolia. Of the three species Casuarina equisetifolia with a light intensity on the floor of 49.5% was the least shading one, followed by Eucalyptus tereticornis with 43.6% and Acacia auriculiformis with 30.6%. Eucalyptus was found to permit luxuriant undergrowth, so also casuarina. The above ground phytomass was 1.431 kg drymatter/m2 in Eucalyptus and 1,176 kg/m2 in Casuarina. But Acacia was found to inhibit undergrowth (0.183 kg/m2 ). Even the little undergrowth that was permitted by it comprised mostly of its own seedlings. The undergrowth in Eucalyptus comprised mostly of woody species (65.5%) while that of casuarina comprised mostly of grasses (68.5%). The presence of coal cinders had caused a rise in the soil pH, organic matter content, available Nitrogen content and available phosphorus content of the soil. The lowest pH value in the top soil was found in Acacia soil 4.31. Eucalyptus soil had 4.69 and Casuarina soil had 4.94 compared to the barren laterite (5.16) and the barren laterite with coal cinders (5.32). At the depth of 30-45 cm, the pH values were 4.85 in Acasia soil, 5.17 in Casuarina soil and 5.32 in Eucalptus soil. The barren laterite had a pH of 5.24 and in the barren laterite with coal cinders it was 5.42. The pH at 60-70 cm depth was 4.88 in Acacia soil 5.24 in Casuarina soil, 5.33 in Eucalyptus soil, 5.36 in barren laterite and 5.52 in barren laterite with coal cinders. All the three species reduced the pH of the soil. But Acacia auriculiformis was found to lower the pH of the soil more than the other two. pH increased with the depth in all the treatments. The organic carbon contents in the top soils were 0.57% in Acacia, 0.41% in Eucalyptus, 0.49% in Casuarina, 0.39% in barren laterite and 0.43% in barren laterite with coal cinders. The organic matter content was found to decrease as depth increased in all the treatments. There was a general rise in the organic carbon content of the soils due to the impact of the three species with the maximum in Acacia soils and the minimum in Casuarina soils. The available Nitrogen content in the top soil was 1277 kg/ha in Acacia, 1165 kg/ha in Eucalyptus, 1098 kg/ha in Casuarina, 874 kg/ha in barren laterite and 963 kg/ha in barren laterite with coal cinders. There was a reduction in the available Nitrogen content as the soil depth increased in all the treatments. All the three species caused an increase in the available Nitrogen content of the soil, the highest being observed in Acacia auriculiformis followed by Eucalyptus tereticornis. The available Potash content of the soils did not record any change under the different species. The available phosphorus contents of the top soils were 92.7 kg/ha in Casuarina, 90 kg/ha in Eucalyptus, 81.5 kg/ha in Acacia. 79.3 kg/ha in barren lateric and 87.4 kg/ha in the barren laterite with coal cinders. There was reduction in the content of the nutrient as depth increased in all the treatments. In Acacia soils the content of the available Phosphorus had decreased. Regarding the general observations, Acacia auriculiformis showed pronounced branching habits while Eucalyptus and Casuarina had more or less clean boles. Pests and diseases were not observed excepting the pink disease (c.o. Corticium salmonicolor) in Eucalyptus. Crows and rodents were the principal representatives of wild life in the plantion. Honey bees commonly foraged the inflorescence of Acacia. Acacia auriculiformis proved itself to be a highly promising tree for energy plantations and for afforesting sites dumped with coal cinders and for sites offering little protection from anthropogenic influences and grazing. It also improved the organic matter content and available nitrogen content of the soil and was free from graziers. But at the same time there were also unwelcome effects due to Acacia such as increasing the acidity of the soil and supressing undergrowth. It also tended to be highly branching. Eucalyptus tereticornis also was found to be good in growth and biomass production and could be recommended for similar sites. The species also enriched the soil by increasing the contents of organic carbon and available Nitrogen. Though it too reduced the pH of the soil, the species was found to support luxuriant undergrowth and was spared by graziers. Casuarina equisetifolia was a less suitable species for such a site as seen from the performance of the species. It suffered heavily from browsing and showed lesser survival growth and yield. But the species increased the organic carbon content and available Nitrogen content of the soil and permitted luxuriant undergrowth especially grasses.
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
Anatomy and utilization of two cane species of Kerala
(College of Forestry, Vellanikkara, 1988) Mohan, Varghese; KAU; Bhat, K M
Variation in certain anatomical and physical properties has been investigated and compared in two rattan species, viz. Calamus thwaitesii and C. travancoricus, the former representing the larger diameter and the latter possessing small-diameter canes of kerala. Five stems possing more or less similar number of internodes have been sampled in each of two species. There were significant differences between the two species in certain physical properties such as length and diameter of internode, stem “wood” density and initial moisture content although volumetric shrinkage did not differ appreciably. Similarly, quantitative data for anatomical properties such as corted percentage, number of vascular bundles per unit area, vascular bundle diameter, xylem and phloem percentage, metaxylem vessel element and fibre dimensions were markedly different between the two species while the fibre percentage had almost similar values. With the exceptions of internode size and fibre width, the mean physical and anatomical properties in each species showed definite patterns of longitudinal variation, which could be best explained using quadratic regression models. However, patterns of longitudinal variation were different between the species in volumetric shrinkage, number of vascular bundles per mm2, vascular bundle diameter, phloem percentage, metaxylem vessel element and fibre length. The most important useful features in distinguishing between the two species are internode length, stem diameter, epidermal cell and its lumen shape, diameter and frequency of vascular bundles as well as the diameter of wide metaxylem vessels. The most important determining factors of “wood” density are fibre percentage, fibre wall thickness and lumen width as well as the diameter of metaxylem vessels although features like the size and number of vascular bundles per unit area also influences this property. Volumetric shrinkage and moisture content are inversely related to the density of “wood”. With higher density owing to more thick walled fibres and narrower wide metaxylem vessels, basal portion of the stem is harder and heavier than top portion.
Open Access
Evaluation of provenances for seedling attributes in teak
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 1996) Jayasankar, S; KAU; Luckins Babu, C
A randomized block design experiment involving the performance of selected provenances ie., Arienkavu, Konni, Malayattur, Nilambur, Parambikulam, Wynad and Thrissur (Local provenance) of Tectona grandis Linn. F. initiated during June, 1995 was used for the present investigation. The objective of the study included qualifying the seed characters, growth parameters, physiological and anatomical characters, root growth potential, field establishment and also elucidating the extent of nutrient uptake pattern, besides characterising the nutrient status dynamics. Seed characteristics like mean number of seeds per kg, 100 seed weight, purity percentage and individual seed parameters were found to vary significantly among the provenances tested. Parambikulam was found to be superior to other provenances, while local provenance recorded the least values for most of the parameters. Germination behaviour of teak provenances in the laboratory varied considerably among provenances. The overall performance was better in Konni which recorded a high germination percentage, peak value and MDG. Malayattur was showed to be inferior in these respects. Shoot, root growth, biomass allocation pattern, RGR and NAR were followed the trend that, Parambikulam, Nilambur and Malayattur consistently registered better growth rates in most of the stages of experimental period while, local provenance recorded the least values. Physiological parameters like LDR, transpiration rate, leaf water potential and RWC were influenced considerably among the provenances. Anatomical character like stomatal frequency was also varied among provenances throughout the period. Concentration of nutrient in the different plant parts and uptake pattern were found to be higher in Malayattur, Nilambur and Parambikulam especially with a high magnitude of N use efficiency. Local provenance registered a low accumulation of nutrients in different plant parts. Root growth potential studies showed significant variation among the provenances. Malayattur and Nilambur provenances had relatively higher values in RGP. While, Thrissur recorded a poor growth performance in this respect.
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.

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