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Subject: Forestry × Author: KAU × End date: 2017 × Start date: 2017 ×
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    ThesisItemOpen Access
    Standardisation of preservation techniques of coconut (Cocos nucifera L.) palm wood
    (Department of Wood Science, College of Forestry, Vellanikkara, 2017) Jeeshma, V J; KAU; Anoop, E V
    Coconut (cocos nucifera L.) palm wood belongs to the class of perishable timbers which can be used as an alternative wood sources with affective preservation. Preservative treatment of coconut wood can enhance the service life of coconut service life of coconut wood. The objective of this study was to develop appropriate preservative methods to treat sawn coconut wood under the prevailing eco-climatic conditions in Kerala and to evaluate the effect of different factors on the treatability of coconut wood. Wood samples were treated with inorganic (Copper Chrome Boron- CCB and Borax Boric Acid-BBA) and organic preservatives (Cashew Nut Shell (CNS) liquid, need oil and turpentine). Diffusion and pressure treatment were deployed for inorganic preservation and organic preservatives were investigated only through diffusion treatment. Wood samples were air dried to a moisture content of about 50 per cent and total of 354 sampled belonging to high and medium density wood were treated with preservatives. Diffusion treatment of inorganic preservatives in high and medium density wood showed no significant difference in retention whereas significant difference was observed for penetration percentage. For pressure treatment, retention and penetration were significant in high density wood whereas medium density wood showed only significant retention. A proportionate relation existed between the solution concentrations and the two observations- overall retention and penetration percentage. Relation of diffusion period and retention in high density wood showed no uniform pattern while, an increasing trend was seen in medium density wood. Penetration depth followed an increasing pattern under increasing treatment duration in the two density classes. Among the two treatment methods, pressure treatment performed better than diffusion treatment. Absorption percentage of organic preservatives was non-significant among treatment factors (chemicals and duration), and their interaction in the two density classes. The study found that sawn coconut wood samples could be effectively treated with preservatives complying with the prescribed retention and penetration percentages as per the different standards and therefore, could be used as a potential substitute for conventional timbers.
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    ThesisItemOpen Access
    Characterisation of phytopathogenic fungi in nursery seedlings of Tectona grandis L.F, Swietenia macrophylla King and Cassia fistula L. In Central Kerala
    (Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2017) Kiran Mohan; KAU; Gopakumar, S
    Disease free planting stock significantly ensures a better field survival while at the same time reducing the burden of economic loss. Teak, mahogany and Indian laburnum which are extensively used for afforestation programmes in India are attacked by several fungal pathogens at nursery stage. Hence an investigation was undertaken to identify the fungal diseases associated with above mentioned seedlings in Kerala and also to assess the efficacy of selected fungicides and bio-control agents against these pathogens through in vitro studies. Purposive sampling survey was conducted in eighteen Government tree nurseries of Thrissur (10 nos.) and Palakkad (8 nos.) districts during the summer (February-May), monsoon (June- September) and post monsoon (October-January) seasons for monitoring the occurrence of fungal diseases and collection of diseased samples. Out of the fifteen fungal diseases observed, nine was from teak, two was from mahogany and four was from Indian laburnum seedlings. Fungal diseases observed from teak seedlings included teak leaf blight (TLB), teak leaf spot-1 (TLS-1), teak leaf spot-2 (TLS-2), teak leaf spot-3 (TLS-3), teak leaf spot-4 (TLS-4), teak collar rot, teak root rot-1 and teak root rot-2. In the case of mahogany, mahogany leaf blight-1 (MLB-1) and mahogany leaf blight- 2 (MLB-2) were noticed. Four foliar diseases were observed from Indian laburnum viz., Indian laburnum leaf blight-1 (ILB-1), Indian laburnum leaf blight-2 (ILB-2), Indian laburnum leaf spot-1 (ILS-1) and Indian laburnum leaf spot-2 (ILS-2). TLB was found to be most severe foliar disease in teak and maximum Percent Disease Index (PDI) and Percent Disease Severity (PDS) of 63.50 and 18.72 per cent respectively were recorded from Vellanikkara in Thrissur district. Collar rot (PDI 18%) was observed only from Chettikkulam in Thrissur district. Chittur (Teak root rot-1) recorded maximum PDI of 34.5 per cent. In mahogany, MLB-1 observed from Aatoor recorded maximum PDI (57.50 %) while maximum PDS (10.4%) was recorded from Vellanikkara. In Indian laburnum, ILS-2 observed from Vellanikkara recorded maximum PDI (38.50%) as well as PDS (5.76%). TLB showed positive correlation with temperature while it showed a negative correlation with relative humidity. TLB symptoms originated as small irregular grey to blackish spots surrounded by yellow halo scattered over the lamina. Symptoms of teak leaf spot (TLS-1, TLS-2, TLS-3 and TLS-4) started as small necrotic spots and were generally observed in old, mature leaves. Leaf blights in mahogany (MLB-1 and MLB-2) was characterized by necrotic regions with definite black margin. Leaf blight diseases of Indian laburnum (ILB-1 and ILB-2) were observed as necrotic regions in the tip as well as base of the leaf. Leaf spots (ILS-1, ILS-2) occurred as medium sized spots on the upper surface of the leaf. Pathogenicity of the thirteen isolates was proved by Mycelial Bit Inoculation Method (MBIM) as well as Micro Droplet Inoculation Technique (MDIT). Spore suspension method was adopted for collar and root disease. Cultural as well as morphological characters of pathogens were studied and morphological identification done with the expert advice of National Centre for Fungal Taxonomy (NCFT), New Delhi. Molecular identification of selected pathogen was done at Rajiv Gandhi Centre for Biotechnology (RGCB), Thiruvananthapuram. The causative pathogen in TLB was identified as Curvularia eragrostidis, in TLS-1 as Alternaria alternata, in TLS-2 as Macrophomina phaseolina, in TLS-3 as Botryodiplodia theobromae, in TLS-4 as Colletotrichum gloeosporioides, collar rot pathogen as Alternaria alternata, root rot-1 pathogen as Fusarium solani and root rot-2 pathogen as Fusarium oxysporum. Olevea tectonae was confirmed as the pathogen of teak rust fungus. MLB-1 and MLB-2 were caused by Curvularia geniculata and Alternaria alternata respectively. In Indian laburnum, Alternaria alternata (ILB-1), Colletotrichum gloeosporioides (ILS-1) and Phoma cassiocarpa (ILS-2) were the disease causing pathogens. The identity of obligate parasite causing ILB-2 was also confirmed as Cercospora sp. in vitro evaluation studies revealed that carbendazim 12% + mancozeb 63%, difenoconazole 25EC, carbendazim 50WP to beefficient against teak foliar diseases. Similarly carbendazim 12% + mancozeb 63%, carbendazim 50WP, hexaconazole 5EC showed promising results against collar and root diseases of teak. Carbendazim 12% + mancozeb 63%, hexaconazole 5EC, cymoxanil 8% + mancozeb 64%, propineb 70WP, carbendazim 50WP were observed to be efficient against foliar diseases of mahogany. In Indian laburnum, hexaconazole 5EC, difenoconazole 25EC, carbendazim 50WP, carbendazim 12% + mancozeb 63% were found to be efficient. The fungal antagonist Trichoderma asperellum showed promising results compared to the bacterial antagonist Pseudomonas fluorescens.
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    ThesisItemOpen Access
    Cause-consequence analysis of human-wildlife conflict at Nemmara forest division, Kerala
    (Department of Forest Management and Utilization, College of Forestry, Vellanikkara, 2017) Anand, R; KAU; Gopakumar, S
    A study titled “Cause-consequence analysis of human-wildlife conflict in Nemmara forest division, Kerala” was conducted during 2013-2017. The main objectives of the study were to portray the nature and distribution of human-wildlife conflict, study the land use and land cover change pattern. Another objective of the study was to assess the attitude and awareness of the people including the victims of human-wildlife conflict about forest conservation and human- wildlife conflict. The observations of the study would be made useful to evolve location specific management strategies at Nemmara Forest Division. A detailed pre tested questionnaire was used to gather information regarding socio-demographic details, land use and land cover change patterns, human wildlife conflict data, crop farming details and also attitude and awareness of the people. A total of 398 individuals were surveyed from Alathur, Kollengode and Nelliyampathy ranges of the forest division. Participatory Rural Appraisal (PRA) methods such as oral history, time line and problem tree methods were used to collect additional information. The study found out that major conflict areas were along the fringes of the forest areas. The type of conflict even though was mainly crop raiding, the nature of damage and the animal causing the damage were found to be different in different ranges in the forest division. Over the past 30 years there was significant change in the land use and land cover in the division. Over all, cropping pattern has changed from food crops to cash crops. The number of wild animals has increased and this was portrayed as the main reason for human-wildlife conflict. The people found the forest department as the best responsible agency to look up to take action regarding conflict mitigation and were also ready to join hands with them to resolve such issues. Even though the people had a positive attitude towards forest conservation and wildlife they were not satisfied with the conservation policies and human-wildlife conflict mitigation schemes of the government. The people did not favour compensation or insurance schemes as a mitigation strategy towards crop raiding mainly because of the low compensation amounts and difficulty in applying for such schemes. Site specific plans, based on the data generated from this study can be used to develop not only location specific plans but also both animal as well as people specific plans for conflict management and mitigation.
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    ThesisItemOpen Access
    Screening of Ailanthus triphysa (Dennst.) alston. for preferred match wood qualities
    (Department of Wood Science, College of Forestry, Vellanikkara, 2017) Bill Nelson, Paul; KAU; Anoop, E V
    Ailanthus triphysa, a member of the family Simarubaceae is an important tree with regard to match manufacture. Twenty Candidate plus trees (CPTs) were selected from 10 panchayats across two districts (Thrissur and Palakkad) in Kerala to study the variation in wood properties and the growth parameters of their half-sib progenies during 2013-2017. Core samples were collected to analyse the anatomical properties and fibre indices between the CPTs, which was later found to vary significantly at one percent level. Morphological and growth parameters were observed in the half-sib progenies of the selected trees both in nursery and field condition for 150 days each. The morphological parameters like height, collar diameter, root length, leaf area, number of leaves etc. were found to vary significantly at nursery but not throughout the study period. Relative Growth Rate, Absolute Growth Rate and Net Assimilation Rate did not show significant variation among the seed sources. Field performance of the progenies was evaluated at Aaramkal, Vellanikkara, Thrissur, Kerala in RBD. Height and collar diameter varied significantly initially but the differences were not significant for collar diameter from 90 days after planting. However, survival percentage did not show any significant difference between the progenies. FCV AT 1 showed the maximum height growth at 150 days after planting. A questionnaire survey was conducted to access farmers’ perception towards growing raw materials for match manufacture. The respondents had an overall positive approach toward tree farming. The majority of the respondents were confident that scientific guidance will help them in increasing the yield.
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    ThesisItemOpen Access
    Wood property profiling of coconut palms grown in different agro-climatic zones of Thrissur District, Kerala
    (Department of Wood Science, College of Forestry, Vellanikkara, 2017) Alex, K George; KAU; Anoop, E V
    Wood anatomical, physical and mechanical properties of samples collected from 51 coconut palms belonging to three age groups viz., 15-25 years (young), 35- 45 years (mature) and 55-65 years (over mature), grown in three agro-climatic zones (Malayoram, Central midland and Coastal sandy) of Thrissur district, Kerala were profiled in this study. Dermal, sub-dermal and core wood from each sample were used for assessing physical and anatomical properties and samples of density above 650 kg m -3 were selected for profiling mechanical properties. Nested analysis of variance was carried out to analyse the variation in coconut palm wood properties due to location, age and radial position. Most of the physical, anatomical and mechanical properties did not vary significantly across agro-climatic zones and age groups. However, across age groups, basic density, vascular bundle percentage, fibre lumen diameter, fibre wall thickness and compression parallel to grain (maximum load and compressive stress at maximum load) were found to vary significantly. Along the radial positions there was significant difference in physical and anatomical properties. Basic density, being highly positively correlated with mechanical and anatomical properties, estimation of density can be used as a key to determine end use under field conditions for potential utilization at the industrial level.
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    ThesisItemOpen Access
    Geographical Indications status for Nilambur Teak (Tectona grandis L.f.)
    (Department of Wood Science, College of Forestry, Vellanikkara, 2017) Swathy, M Haridas; KAU; Anoop, E V
    A study on the “Geographical Indications status for Nilambur teak (Tectona grandis L.f)” was carried out in teak plantations of Nilambur and in Central Kerala (Thrissur, Palakkad and Ernakulam) during 2014-2016. The investigation focused on analyzing the potential of securing Geographical indications status for Nilambur teak by exploring the historical importance of Nilambur teak with the help of PRA tool timeline, comparing its wood quality with other National and International provenances and analysing the soil properties and climatic factors that are responsible for the uniqueness of Nilambur teak and to assess the popularity of Nilambur teak among the timber traders. Wood properties of three best teak growing plantations in Nilambur viz., Aryavallikkavu, Elencheri and Kanakuthu were analysed. Growth parameters such as girth at breast height (GBH) and height were taken from the selected trees; also non destructive testing methods (NDT) using Pilodyn (6J) and Tree Sonic Timer (FAKOPP) were used to estimate wood physical and mechanical properties. Heartwood percentage and colour were estimated in the teak discs collected from the selected plantations. No significant variation was found in Pilodyn penetration depth (PPD), Stress wave velocity (SWV), dynamic modulus of elasticity, heartwood percentage and GBH between the three plantations of Nilambur region. Heartwood colour determining components (hue, value and chroma) did not show any significant variation between the sites. In general, there was not much variation in physical and mechanical properties of teak grown in the various sites of Nilambur region. For analyzing soil properties, two soil pits of 1 m * 1 m* 1 m were dug from each of these plantations. Soil samples were collected from 0-20, 21-40, 41-60, 61-80 and 81-100 cm depths. The soil texture was sandy loam in all the sites and at different depths of soils in the selected teak plantations. Soil pH ranged from 6.05 to 4.79 from top to bottom layer indicating moderate acidity which measured with soil depth in teak plantations. The bulk density values were generally higher in the deeper layers of the soil. The mean bulk density values were in the range 1.0 to 1.92 g/cm3. Soil N, P, K content was lower in all the three sites compared to natural forests. Organic carbon content varied from 1.83 to 0.25 per cent with depth. Popularity and reputation of Nilambur teak among the traders studied through a questionnaire survey in sawmills of Thrissur, Palakkad and Ernakulam revealed that Nilambur teak has a high reputation among sawmill owners. Among teak woods available in the timber market of Central Kerala, Nilambur teak fetches high market prices per cubic feet. It is concluded that Nilambur teak has good potential for securing Geographical Indications status owing to its historical importance, good reputation, excellent colour, higher heartwood percentage and better strength properties.
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    ThesisItemOpen Access
    Ecoanatomical characterisation and development of anatomical key of selected mangrove species of west coast of India
    (Department of Wood Science, College of Forestry, Vellanikkara, 2017) Anju S Vijayan; KAU; Anoop, E V
    The present investigation focused on the ecoanatomical characterisation of the wood of 17 selected true mangroves collected from 10 locations in the Western Coast of India. A total of 221 characters listed in the IAWA (International Association of Wood Anatomists) list of card key features were studied for each species as there is a felt need for creating databases of mangrove wood anatomy which allows to quantify the relative amount of intra- and interspecific variation, as well as variation within and between the mangrove genera. Mangrove wood from West Coast of India is characterised by diffuse-porosity, scalariform to opposite vessel wall pitting, scalariform perforations with few bars or large number of bars. Most mangrove family members were found to have simple perforations, septate or non septate fibres with distinctly to minutely bordered pits, bordered, half bordered to simple pits, paratracheal parenchyma, apotracheal and banded parenchyma. Heterocellular to homocellular rays with mostly procumbant cells with one or several marginal row of square/upright cells was also observed in these mangrove genera. Short numerous vessels with small dimension and vessel grouping were also common. The most advanced characters like vestured pit, helical thickening, crystals and vessel occlusions were present in majority of the samples. A perforated card key based on the IAWA list of microscopic card features for mangrove identification was also prepared. The development of an IAWA based anatomical key will be helpful for the identification of mangrove species based on wood anatomy. The ecoanatomical characters such as vessel diameter, vessel frequency, vessel grouping, type of vessel plate, lateral wall pitting, type of pits of true mangrove species were studied and compared with data from their nearest upland relative. The ecoanatomical features of wood of mangrove species are correlated with xeromorphic nature of their upland relatives. Because of the highly variable and stressful environmental condition, the mangroves developed certain strategies and adaptations during their evolution. These special morphological and physiological adaptations made it for the mangrove species to survive in these conditions in contrast to their upland relatives. A safe hydraulic architecture is only one of the alternative ways for a plant to be able to survive in water stress situations. The modification of xylem hydrological structure of mangrove wood helps to balance safety versus efficiency of water transport system. These modifications of wood structure due to ecological conditions are the driving force to evolution of wood anatomy. Thus the evolution of mangrove genera has been shown to be likely driven by environmental condition and not by phylogeny. The general pattern of wood anatomy of mangrove genera of different families indicates convergent evolution. These trends of wood anatomy in mangrove species provide new examples of phenotypic plasticity in angiosperms. To ensure safety, certain primitive structures such as bordered pits, scalariform vessel plate, scalariform, transitional, opposite lateral wall pitting and vessel bars still persist in the true mangrove genera of the present investigation. Thus the development of wood anatomical characters in mangrove genera were an example of heterobatmy. The presence of mostly primitive wood character states suggest an unbroken occupancy of stressful habitat by its ancestral genera. Mangrove occurs in different families in which the gamut of wood specialization ranges from advanced to highly advanced features. Rhizophoraceae members were found to be the most primitive ones with less specialization whereas the other mangrove species were found to have highly advanced wood anatomical characters.