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Open Access
Physico-chemical characterization of gum-oleoresin from Ailanthus triphysa(Dennst.) Alston and effect of ethephon on gum-oleoresin yield
(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2020) Latha, K J; KAU; Vidyasagaran, K
Gum and resins are natural bio-polymers having number of applications in pharmaceutical and food industries. Most of them are regarded as bio-degradable and safe because of their bio-compatibility, low cost, non-toxic, processing, environmental friendly and local availability. It is viable income source for thousands of forest dwellers. So the present study entitled “Physico-chemical characterization of gum-oleoresin from Ailanthus triphysa (Dennst) Alston and effect of ethephon on gum-oleoresin yield” was carried out at Arboretum, College of Forestry, Vellanikkara during the year 2018-2019. The main objective of the study was to assess the effect of different concentration of ethephon on gumoleoresin production in Ailanthus triphysa and also study the effect of diameter classes on production. The physical properties such as Solubility, pH, Viscosity, Moisture level, Color parameters, Ash content and chemical compounds were also determined as part of the study. A total of twenty-four trees were selected for conducting the study in which two girth classes (70-110cm, 111-150cm), four chemical treatments, each with three replications were taken. Data analysis was done on monthly intervals, showed significant difference in girth class on resin production in the months of June, July, August, November, December and April and in other months it found non-significant. It was observed that girth class G2 (111cm-150 cm) showed more yield compared to G1 (70-110). It was statistically found significant difference in gum-oleoresin yield due to different concentration of ethephon treatments. T4 (3.9%) ethephon treatment gave more yield (817.99gm) compared to other treatments, where T1 (control) gave very less yield (226.16gm). The exudation of gum-oleoresin was found to be more in post monsoon (55.06gm) followed by monsoon (43.78gm) and least during summer (27.01gm). Interaction between different ethephon treatment and season was found to be non-significant. 116 The physical and chemical properties of gum-oleoresin were studied and it indicated the gum-oleoresin was found to be strongly acidic, highly soluble in xylene and least in chloroform and in case of water, it absorbs water and swell. Moisture content was 5.17%, pH observed was 5.5, Colour of the gum-oleoresin observed was pale yellow to dark reddish brown and Viscosity observed was 2340 cps and 695 cps. Heavy metals like K ˃ Mg ˃ (Ca) ˃ (Ir) were detected. Chemical compounds were identified by using GC-MS. Total 18 compounds were identified from Acetone extract of gum-oleoresin in GC-MS, the major constituents of the chemical compound were beta.-caryophyllen followed by Tetradecane and 1,3,3-trimethyl-2-(2-methylcyclopropyl)-1-cyclohexene and 1- octadecene constitute least contribution, where as in methanol extracts, 16 compounds were identified, most abundant compound was Caryophyllene followed by 1,2-benzenedicarboxylic acid and bicyclo, the least abundant constituent was found to be 3-hexadecene. The correlation studies of bark thickness on production of gum-oleoresin were found to be significant with correlation coefficient 0.42. The climatic parameters like rainfall, relative humidity, temperature was found to be non-significant on production of gum-oleoresin.
Open Access
Provenance evaluation of acacia mangium wild for growth and wood traits
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 2015) Ringyao, Jajo; KAU; Santhoshkumar, A V
A provenance evaluation of A. mangium was conducted in 14 year old plantation at Livestock Research Station, Thiruvazhamkunnu, to understand the variation in growth and wood traits among the provenances. Ten provenances and one local seed source was used for the trial. The provenances had high survival percentage (77.44%), but did not differ significantly between provenances. Significant differences between provenances were found in tree height, while they were on par for DBH, volume, tree form and branching habit. The provenances of Kuranda, Arufi Village, Upper Aramia, Oriomo, Balimo and Binaturi were taller than the rest. Heritability of growth attributes was highest for height (63%). Morphometric traits of seeds were found to be significantly different between the provenances. Arufi Village provenance was found to be better than the other provenances for the traits. Seed weight and seed width were found to be strongly correlated with seedling height. Variation in germination energy, germination value and germination period were also significantly different between provenances. Lake Murray provenances showed the best performance in most of the parameters studied for germination. No significant differences between provenances were observed for germination capacity. Germination parameters are under moderate to high genetic control. Significant differences were noticed among the progenies of the provenances in height, while they did not differ in terms of collar girth and RGR. The provenances differed significantly in physical properties of wood, but not in mechanical properties. The provenances differed significantly for heartwood only at the base, while basic density was significantly different at all the height levels. Density was significantly and positively correlated with fiber length and slenderness, but negatively with fiber diameter and fiber wall thickness. The variations in fiber morphology between the provenances were also found to be significant. However, runkel ratio, flexibility and rigidity coefficient did not differ significantly between the provenances. Wood properties of the provenances were under strong genetic control. Based on the study, Tully-Mission Beach, Arufi Village, Kuranda, Upper Aramia, Lake Murray and Binaturi provenances can be recommended for growing under Kerala condition.
Open Access
Genetic diversity and population structure of two disjunct natural populations of syzygium travancoricum gamble.
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 2016) Mohammed Anees, P V; KAU; Santhoshkumar, A V
A study was conducted to observe the reproductive biology of the critically endangered species, Syzygium travancoricum Gamble, and to compare the variation between two geographically disjunct populations of the species situated at Kalasamala and Kattilappara. A series of investigations on the phenology, floral biology, morphology, flowering, and fruit set were carried out to study the reproductive biology. The two populations were compared to assess the variation in terms of population structure, morphology, wood anatomy and seed bank. The study revealed that, flowering occurred in S. travancoricum after a dry period and the fruiting occurred just before the onset of rain. The inflorescence of the species was axillary cymose with white, calyptrate flowers. Mass flowering was observed in S. travancoricum, but, when compared to other syzygium species, number of flowers produced per tree was less. The number of flowers setting to fruits was also poor. The natural regeneration from the seeds in the site too was poor. The seeds that germinated below the trees died in the seedling stage itself. The pollen viability studies revealed that the percentage of pollen germination was poor in S. travancoricum. The analysis of the seed germination assay indicated that seed germination was also poor in the species. The germinated seeds in lab too died at the seedling stage itself. The observations related to the population comparison revealed that, there were a lot of variations between the two populations in most of the characters. The biometric characters like tree height, GBH, and crown area showed significant differences between the two populations. In the case of leaf morphological characters such as leaf length and breadth, there were significant variation between the populations. The species associated with S. travancoricum was different in Kalasamala and Kattilappara. The relative density of the species was different in the two populations. The two populations showed significant variations in the case of wood anatomical characters. The seed banks too differed significantly between the two sites. The study concluded that the constraints such as, lesser flower production, poor fruit set, lower seed germination, poor seed viability could be the main causes of the rarity of S. travancoricum. The study further showed that the two populations have considerable differences between them, either environmental or genetic.
Open Access
Wood quality evaluation of tree species raised in research trials of the Kerala forest department at various localities
(Department of wood Science, College of Forestry, Vellanikkara, 2012) Sindhumathi, .C.R.; KAU; Anoop, E.V
A study entitled “Wood quality evaluation of tree species raised in research trials of the Kerala Forest Department at various localities” was conducted in the College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur during the period 2010-2012. The objective of the study was to evaluate the wood quality of Pterocarpus dalbergioides Roxb., Swietinia macrophylla King. and Pericopsis mooniana (Thwaites) Thwaites, raised in research trials of the Kerala forest department at three localities, viz., Mananthavady research range at Wayanad, Olavakkode research range at Palakkad and Nilambur north research range at Nilambur districts, Kerala. Increment core samples and wooden blocks were collected at breast height from trees, selected at random for each species. These samples were subject to intensive investigations to explore the radial variation in anatomical properties as well as variation between species. The study revealed that most of the anatomical properties varied significantly within species and between species. Tree species were also felled to assess the strength characteristics as well as to study the various physical properties. Specific gravity was higher in P. mooniana, the other two species showing similar values. Heartwood – sapwood ratio showed significantly higher value in S. macrophylla, whereas the other two species were at par. Tangential shrinkage showed higher value compared to radial shrinkage in all the three species. Results revealed that P. mooniana exhibited better strength properties which was almost similar or even better than teak as reported by Sekhar (1988). P. dalbergioides showed lower values for strength properties when compared to natural grown P. dalbergioides (Limaye, 1933). Even though P. mooniana showed higher strength properties compared to the two species, overall results revealed that all the three species has good potential for being used as various solid wood purposes. Regression analysis revealed that P. mooniana and P. dalbergioides showed linear relationship between specific gravity and anatomical properties. The present results on wood quality can be used as a baseline data for future tree improvement aspects of these species with reference to wood quality and bring out their potential utility for future afforestation programmes and various end uses.
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
Impact of invasive alien plants on understorey vegetation in Wayanad wildlife sanctuary
(Department of Natural Resource Management, Vellanikkara, 2018) Vishnu Chandran, M; KAU; Gopakumar, S
The present study “Impact of invasive alien plants (IAP) on understorey vegetation in Wayanad Wildlife Sanctuary” was conducted in three vegetation types (Plantation, NF and Vayal) of WS II part of the sanctuary. The distribution characteristics of selected invasive alien species (IAPS) viz. Lantana camara L., Senna spectabilis (DC.) H.S. Irwin and R.C. Barneby and Chromolaena odorata (L.) R.M. King & H. Rob and the impact of these invasive alien species on the regeneration of other plant communities were studied and compared. L. camara and C. odorata invaded all areas of the sanctuary except in the borders of Kurichiat and Sulthan bathery forest ranges. Lantana invasion was high in the Kurichiat RF (Reserve forest) and Rampur RF. Chromolaena invasion was found to be high in Mavinahalla and Kurichiat RF. In WS II part of the sanctuary, S. spectabilis was mainly distributed along the boundaries of Sulthan bathery and Muthanga ranges. In Muthanga, Senna invasion was extended up to “Kakkapadam” (2.5 km from Muthanga station). Among the IAPS, Chromolaena showed the highest density in all the three vegetation types, while the density of Senna was lowest in all the three vegetation types in WS II area. The density of Chromolaena in plantation and NF was 4943.52 ± 1079.07 and 4996.47 ± 1484.42 respectively. The density of Lantana in plantation and NF was 322.35 ± 88.18 and 85.42 ± 29.55 respectively. The density of Senna in plantation and NF was 63.5 ± 31.66 and 49.74 ± 23.93 respectively. Senna invasion was absent in vayal. Vayal showed highest density of Chromolaena (5810.59 ± 1262.43). Chromolaena had the highest percentage cover in both plantation and vayal. In NF, Lantana has (14.2 ± 2.8) the highest percentage cover. In all the three vegetation types, Chromolaena had the highest frequency and abundance. Among the seven weed category areas identified from the study area, highest MSR (Mean Species Richness) was seen in Control (weed free area), followed by L (Lantana invaded) and LC (Lantana and Chromolaena invaded)regions. The lowest MSR was obtained in S (Senna invaded) and CS (Chromolaena and Senna invaded) regions. All the three IAPS negatively influenced the native species richness. But no specific declining trend in species richness was observed during regression analysis. Results of regression analysis showed that, among the three IAPS, C. odorata had the biggest impact on the species richness of native species. It was followed by L. camara and S. spectabilis. Species richness of each growth form (herb & shrub) declined significantly with increasing Lantana, Chromolaena and Senna cover. In the current study, trees and climbers did not show any significant variation with increasing percentage covers of IAPS. For every 10% increase in percentage cover of C. odorata, two native herb species were observed being removed from the study area. At the same time only one shrub species was removed at every 10% increase in Chromolaena cover. For every 10% increase in Lantana cover, one native herb species was removed from the study area of the sanctuary. The species richness of shrubs also declined due to Lantana invasion. On plotting herb species richness against Senna percentage cover, only four herb species were obtained at 50% Senna cover. On further increase in percentage cover of Senna the herb species richness declined linearly and it was decreased to one at 100% Senna cover. It was also found during the study that, in plots where Senna and Chromolaena occured together, the species richness decreased from 86 to 4. Similarly in plots where Senna occured with Lantana and Chromolaena, species richness declined. This probably indicates a dominating interference of Senna on the recruitment of native species and could be because of the impacts of its larger size, big and wider canopy, competitive reproductive ability, allelopathy and a broad, deeper root system. Out of the 125 plant species identified from the sanctuary, only thirteen were observed from Senna invaded region. But during regression analysis it was found that, among the three IAPS Senna has the least impact on native species richness. This may be due to the fact that compared with Lantana and Chromolaena, the invasion of Senna is restricted to only a small portion of Wayanad WLS. But left uncontrolled Senna will soon become a major threat in Wayanad WLS in the near future.
Open Access
Taxonomic inventory and ecology of the rodents and insectivores of Silent Valley National Park,Kerala
(Department of Wildlife Sciences, College of Forestry, Vellanikkara, 2016) Devipriya, K S; KAU; Nameer, P O
Rodents and insectivores accoimts for about 55% of the total mammalian diversity of the world and is tme with Kerala too. Very little studies have been done on the rodents and insectivores of Kerala and no previous studies have been done in Silent Valley NP. Thus, a study was conducted on the taxouomic inventory and ecology of the rodents and insectivores of Silent Valley National Park, which is one of the few remaining pristine rain forests of Kerala. The objectives was to study the species diversity, relative abundance and habitat preference of the rodents and insectivores • such as squirrels, mice, rats and shrews in Silent Valley National Park. Thestudy was carried out from September 2015 to April 2016. The method used for the study was using Sherman Traps technique. 50 Sherman traps were used in each of the four study locations. The study was carried out in two season viz. monsoon and summer and in two habitat types, evergreen forests and grasslands. Six species of rodents and one species of insectivore were recorded fiom Silent Valley National Paric. The rodents recorded were members of Muridae, Sciuridae and Hystricidae families. These includes Rattus yvroughtoni, Gohmda ellioti, Ratiifa indica, Funambulus tristriatiis, Funambulus sublineatus and Hystrix indica. The insectivore observed at SVNP was Suncus murinus of the family Soricidae. Though the rodent and insectivore abundance was more during the monsoon season, there was no significant difference. Similarly though the rodent abundance was more at the evergreen forests, this was also insignificant. Among the microhabitat parameters studied, the climber density has found to be significantly influencing the rodents at Silent Valley. Rattus wroughtoni was the most abundant species of rodent at Silent Valley. Among the rodents of Silent Valley, Ratufa indica is endemic to peninsular India while Funambulus trisiriatus, Funambuhis sublineatus are endemic to Western Ghats. The Funambulus sublineatus is a threatoied species of squirrel seen at Silent Valley and the lUCN Redlist category of this is Vulnerable.
Open Access
Feasibility of forest certification in Marayoor sandal division, Kerala
(Department of Wood Science, College of Forestry, Vellanikkara, 2016) Toji Antony; KAU; Anoop, E V
The study titled “Feasibility of forest certification in Marayoor Sandal Division, Kerala” was carried out during 2015-2016. The main objectives were to find out the potential of implementing forest certification in Marayoor Sandal Division of Kerala by an assessment of the socio-economic status of the stakeholders. It was also intended to assess the management aspects of the Division, particularly to see whether they comply with the sustainable forest management principles and criteria of forest stewardship council (FSC). A pre-tested questionnaire was used to gather information on socio-economic characteristics of the stakeholders’ and for assessing the feasibility of forest certification. A total of 190 respondents from six stakeholders namely, forest dwellers, local community, casual labourers, forest officials, major bidders of Marayoor sandal and scientific community, were surveyed. The study revealed that, the sandal reserve acts as a major source of income to forest dwellers and casual labourers, which shows that, Marayoor Sandal Division plays a key role for meeting their livelihood. The sandal reserve provides a lot of benefits to stakeholders such as forest dwellers and local community. The major threats prevailed in the division were weed growth and grazing. There was no significant association between the socio-demographic variables and the perception of forest dwellerson benefits and threats,whereas for local community the relation showed almost the same pattern except for educational status and threat. The job-related risk was generally less in the sandal division from the perspectives of forest officials and casual labourers. The risk related to night-duty significantly affected the physical and mental capacity of forest officials, while the lack of safe guard measures was reported as a problem by casual labourers. Similarly, there was no significant difference in the job satisfaction with respect to the number of years of work experience. The management activities were satisfactory and the division complied with the government orders, guidelines, forest laws and policies. The strict adherence to the working plan prescriptions helped in the maintenance of the ecology of the division. The correlation between job satisfaction with implementation of management practices and ecological aspects was found to be negatively significant. This indicates that, when the implementation of rigid management practices in Marayoor Sandal Division is necessary on one hand, from the point of job satisfaction of the officials this is highly taxing given shortage of staff. Also, job dissatisfaction was because of the extra burden put on the under staffed workforce destined to ensure quality work. An analysis of the awareness level of a diverse network of experts comprising scientists, academicians, technical experts showed that, they were aware of certification and its importance. Also, the Marayoor Sandal Division was the only legal source of sandal to most of the ayurvedic industries, cosmetic industries and the Hindu temples in the state mainly managed by the Devaswom Boards. The study points to the feasibility of Forest Certification of Marayoor Sandal Division which can help in improving the overall management of the forest division. For this, region-specific P&C pertinent to Marayoor division needs to be formulated. For the implementation of forest certification in India, the National Working Plan Code (2014) should be amended with a view to enhance the practice of forest certification. For ensuring the quality of sustainable forest management particularly that of plantation management, the hard work of staff is needed to be recognised through award of cash incentives.

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