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ThesisItem Open Access Development of experimental kiln-drying schedules for different types of coconut (Cocos nucifera L.) palm wood flooring(Department of Forest Products and Utiliztion, College of Forestry, Vellanikkara, 2021) Shibu, C; KAU; Anoop, E VIn India, there is a significant gap existing between supply and demand for wood and wood products. Several factors influence wood consumption. For example, the construction sector is witnessing a shift to eco-friendly furnishings. Indeed, the eco-friendly amenity of wooden flooring in hotels and houses has contributed to an upswing in commercial wood consumption. In the current scenario, effective utilisation of existing lesser-known species such as Cocos nucifera L. (Coconut palm tree) is gaining prominence. The lesser known wood species will help to meet the domestic demand and may help to bridge the gap between supply and demand of timber. Seasoning of wood is a crucial step for producing defect-free timber for the ease of doing timber work and potential use of available timber. The purpose of this research is to develop experimental kiln-drying schedules for Cocos nucifera L. (Coconut palm tree) for various flooring methods (Tongue & Groove flooring (T&G flooring), Parquetry flooring, and Engineered overlay flooring). The substructure, base kiln-drying schedules were developed based on the Terazawa method (1965), and optimised using Rasialy (1993) classification. The critical conditions of equalizing treatment and conditioning treatment were established in relation to the product's desirable moisture content, which is 12% for general wood flooring products in climatic zone IV (Kerala). High-density wood samples with thicknesses of 25 mm and 50 mm (20 cm x 10 cm in length and width) were used to investigate drying defects under drastic conditions, and schedules for both thicknesses were developed. Similarly, schedules were developed using medium-density wood samples of 25 mm and 50 mm. The moisture content of the experimental samples (2 cm x 2 cm in length and width) was determined using the oven-dry method, and the basic density was determined based on the water displacement method. 83 The experimental kiln drying schedule recommended for 50 mm thick high-density coconut palm wood Tongue and Groove flooring and Parquetry flooring was MT4-B1 (schedule code). Initial Dry Bulb Temperature 39°C (Relative humidity 89%), Initial Wet Bulb Depression 2°C, and Final Dry bulb Temperature 57°C were the critical conditions for MT4-B1. The highdensity coconut palm wood (25 mm thick) is also suitable for Tongue & Groove flooring and Parquetry flooring and the schedule was MT6-B1 with Initial Dry Bulb Temperature 45°C (Relative humidity 90%), Initial Wet Bulb Depression 2°C, and Final Dry Bulb Temperature 62°C. The recommended experimental kiln drying schedule for medium-density coconut palm wood of 50 mm thickness was MT6-D2 as follows: Initial Dry bulb Temperature 42°C (Relative humidity 87%), Initial Wet Bulb Depression 2°C, and Final Dry bulb Temperature 57°C. The schedule for 25 mm thickness medium-density coconut palm wood was MT6-E1, which includes an Initial Dry bulb Temperature of 42°C (Relative humidity 87%), Initial Wet Bulb Depression of 2°C and a Final Dry bulb Temperature of 45°C. The medium-density coconut palm wood only can be used for overlay flooring because of its low strength. All the schedules are made, considering the desired moisture content (12%) for general flooring purposes under the prevailing conditions of Kerala (Relative humidity > 67%) as prescribed by the Bureau of Indian Standards (BIS).ThesisItem Open Access Development of anatomical key for the identification of selected timbers of Kerala(Department of Forest Products and Utiliztion, College of Forestry, Vellanikkara, 2020) Nimmi, Sathish; KAU; Anoop, E VDeforestation poses a massive threat to global biodiversity with illegal logging and the associated trade in illegally sourced wood products. This is a significant contributor to the continuation of unsustainable deforestation rates. Reputed timber traders are also struggling to police their own supply chains and comply with the growing requirement for due diligence with respect to timber ongin and legality. A range of scientific methods have been developed independently with the potential to provide the required identification information. Wood anatomy is considered as a hi^y specialised science discipline which is used in combination with various technologies in forensic timber identification. Wood anatomical features are generally considered not prone to changes under normal circumstances and therefore it forms the basis of wood identification. Analysis can be undertaken at both the macroscopic and microscopic scale, but microscopic examination is usually required to achieve a diagnostic identification. Different features of interest in this scenario include cell size, arrangements of different elements, cell proportion and most importantly, specific gravity. There are thousands of species of trees fi:om which timber can be obtained, each with different rates of growth, structural properties and degrees of durability. Some timbers are highly decorative, some are very strong, some have good resistance to rot - in fact almost every species of wood has features that can be good in some uses, but not so good in others. Therefore, knowing what type of wood you have in fi-ont of you can be extremely important, either because you may have paid a lot of money for something you didn't actually get, or maybe because the wood you've got is unsuitable for the job you have in mind for it. Timber identification is a skill that must be gained with practice and with a bit of extra help from a skilled wood scientist. The lAWA (International Association of Wood Anatomists) List of Microscopic Features for Hardwood Identification is an important standardized list of characters and terminology that can be used in descriptive wood anatomical studies and identification obtained through comparison to reference materials.. The commonly used keys for wood identification are the dichotomous key, perforated card key and the computer aided identification key. Dichotomous keys are the most simple and easy to use keys. These types of keys have been used for over centuries in biological identification. The multiple entry perforated card type of key was introduced by the Forest Products Research Laboratory in 1936, when a key for the identification of hardwoods based on microscopic features was conducted. Hence, the preparation of anatomical key is very important in the field of wood industries for the identification of the suitable material or the tree. Anatomical keys of different timbers assists in a large way do away with the confusion in the identification of timbers. The anatomical keys can also support the molecular studies like DNA bar coding, molecular markers etc. Wood anatomical analysis is the most frequently used method for taxonomic identification, both on the front-line for screening purposes, and in the laboratory for diagnostic identification. In this study, 20 species of trees were considered in the preparation of anatomical keys for identification. The species of trees used for the study are Acacia auriculiformis, A. Cunn. Ex Benth. , Acacia mangium Willd.. , Albizia lebbeck (L) Benth. , Albizzia odoratissima (L.f) Benth. , Artocarpus heterophyllus Lamk. Artocarpus hirsutus Lamk. , Dalbergia latifolia Roxb. , Dalbergia nigra Fr All Hevea braziliensis (H. B. K.) M.A., Hopea parviflora. Bedd., Intsia bijuga (Colebr.) , Ocotea rodiaei (Schomb) Mez. , Peltogyne paniculata Benth. , Pterocarpus marsupium Roxb., Pterocarpus dalbergioides Roxb. ex DC., Santalum album Linn Swietenia macrophylla king. , Tectona grandis Linn. , Xylia dolabriformis Benth Xylia xylocarpa (Roxb.) Taub.ThesisItem Open Access Integration of DNA barcoding and wood anatomy for the identification of selected timbers(Department of Forest Products and Utilization, College of Forestry, Vellanikkara, 2020) Azhar Ali, A; KAU; Anoop, E VIn the field of wood marketing, the accurate identification of species has greater importance. Traditional methods of wood identification are based on physical characters and anatomical features of the wood species concerned. But they have some major limitations which could be overcome by the integration of DNA barcoding with traditional wood taxonomy methods. This study was conducted to confirm the authenticity of certain wood samples based on their physical and anatomical characters and to create a DNA Barcode database of seven selected timber species that are regularly traded in Kerala. The wood samples of seven tree species viz., Indian Sal (Shorea robusta Gaertn), Mangium (Acacia mangium Willd), Indian sandalwood (Santalum album Linn), Western red cedar (Thuja plicata Donn), Red sanders (Pterocarpus santalinus L.F), Mulluvenga (Bridelia retusa Spreng) and Malabar neem (Melia dubia Cav) were collected from sawmills and timber traders across Kerala and their anatomical and physical properties were studied in detail. The identity of samples was confirmed using computer-aided wood identification software in addition to the use of dichotomous keys. The wood samples were then used for DNA isolation, amplification and sequencing. The detailed study on general features such as colour and odour, physical properties like moisture content and specific gravity and micro-anatomical properties such as the number and distribution of vessels and rays was appropriate to confirm the identity of species as the properties were highly comparable with the existing databases. In further procedures, the DNeasy Plant Mini Kit (Qiagen) with some in house modifications could yield the maximum quantity of DNA for the studied wood species in the current study. Also the samples which are soaked in water yielded maximum amount of DNA even if it was treated with wood chemicals during transits for longevity. PCR amplifications were carried out using COBOL Plant Working Group (2009) recommended universal primers for rbcL, matK, and trnH-psbA, from which the matK region showed reasonable amplification.