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ThesisItem Open Access Standardisation of planting stock production techniques for teak (Tectona grandis Linn.f.)(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2020) Vijayalakshmi, K P; KAU; Jamaludheen, VThe study was undertaken at Tree Nursery of College of Forestry to compare the effect of different pre-treatment methods on seed germination and optimization of fertigation intervals and seed sowing at different spacing for quality teak stump production. Attempt was also made to select ideal potting media and to standardize container type and size for producing quality teak seedlings. The treatment combination of termite scarified seeds + Alternate wetting and drying (AWD)-3 days gave the highest germination percentage (92.33 %). This resulted in 18.56 % increase in germination percent against the 73.77 % in the AWD 7 days alone (Standard Pre-treatment followed). The dual advantages of the treatment combination of termite scarified seeds + AWD-3 days with respect to both high a germination percentage and the lesser number of days required for the pre- treatment of teak seeds is an important highlight. Termite scarified seeds gave the highest collar diameter of 1.46 mm as against the control treatment (0.81 mm) after 30 days of germination. The superiority of this treatment was evident, in most of the seedling growth characters in the nursery also, as in shoot length (6.43 cm), root length (13.04 cm), total seedling length (19.48 cm), dry weight (0.20 g) and vigour index (14.91). Mechanical scarification also has shown advantage over the untreated seeds as it followed as the next best treatment in germination percentage and in most of the early seedling growth characteristics. Hence, in situations where the suitable subterranean termite cannot be assured, mechanical scarification using the mechanical scarifier is recommended. For quality teak stump production, at 180 days, the maximum collar diameter (23.31mm) showed by Fertigation at 7 days interval was significantly superior to all other treatments. Moreover, at 180 days, all the fertigation treatments reached the minimal collar diameter criteria of 1-2 cm were statistically distinct from the no fertigation (control) treatment. All the fertigated treatments attained collar diameter of 2-3 cm criteria for better teak stump production. It is also proved that even the least frequent fertigation at 21 days application resulted in the collar diameter of (22.66 mm) at 180 days of growth period. Hence, fertigation with 0.2 % N: P: K (19:19:19) in equal proportion at 21 days interval can be recommended for producing seedlings for better stump production. Seed sowing at 10 cm x 10 cm also reached required collar diameter for stump production. That means, 1000 numbers of utilisable seedlings are available for stump production from a standard nursery bed of 10 m x 1m at 180 days of seedling growth. At 180 days, the treatment interaction F1 X S3 (Fertigation at 14 days interval X Spacing at 30cm X 30cm) showed the maximum collar diameter (34.88 mm) followed by F2 X S3 and F3 X S3 (32.00 and 31.75 mm), these two were on par with each other. Taking into account the number, the treatment combination S1 X F3 (10 cm X 10 cm with 21 days intervals of fertigation) is recommended as it produces 1000 numbers of seedlings fit for better stump production from a standard nursery bed size of 10 m X 1m. The treatment S1 X F4 (10 cm X 10 cm) with no fertigation also reached the minimal collar diameter (11.51 mm) criteria of 1-2 cm. Good correlation existed between root growth potentials and most of the seedling characteristics needed for good quality teak stump with six months of seedling growth. Among the potting media the maximum seedling length (138.00 cm), collar diameter (8.77 mm), total dry weight (17.77 g) and the highest quality index (0.98) recorded in M3-Soil+ Rice husk+ Vermicompost in the ratio of 2:1:1 as against the standard potting media M5 (Soil+ Sand+ FYM) normally used for raising seedlings. Apart from the observed improvement in plant growth, the production cost of planting stock was found comparable for M3 (soil+ rice husk+ vermicompost) 2:1:1 mixture (₹ 9.09 / plant) as against the cost for standard potting mixture (₹ 9.01 / plant) and the treatment M4-Coir pith+ vermiculite+ perlite was found as the costliest (₹ 13.02 / plant). Both from the seedling quality and from the economic point of view, the treatment M3- Soil+ rice husk+ vermicompost was emerged as the best. Among the polythene bags, 30 cm x 25cm (T1) raised seedling exhibited maximum number of leaves (15.25), leaf area (4025.95 cm2), shoot length (106.89 cm), collar diameter (13.50 mm), the number of primary lateral roots (58.12), length of primary lateral roots (38.96 cm) maximum root length (48.74 cm), total dry weight (60.37 g) and quality index (4.56) at 90 days after transplanting. Among the different root trainers, 300 cc raised seedlings showed maximum number of leaves (11.12), leaf area (435.08 cm2), collar diameter (6.91 mm), shoot length (27.09 cm), root length (23.80 cm), total seedling length (50.90 cm), number of primary lateral roots (51.25), length of primary lateral roots (19.80 cm), leaves dry weight (2.11 g), shoot dry weight (3.46 g), total dry weight (6.61 g) and quality index (0.84) as against the T6-Root trainer of 150 cc (Standard size/control). The production cost of planting stock was found (₹ 9.09 and ₹ 7.89 / plant) for T4-Root trainer of 300 cc and T5-Root trainer of 200 cc and T6-Root trainer of 150 cc - Standard size/control (₹ 6.99 / plant). From the results of the study, it is advisable to adopt root trainer of 300 cc only if the additional cost of ₹ 2.10 can be spent per seedling, otherwise go for the standard size of 150 cc for there was no distinct advantage of adopting the next bigger size of 200 cc. The prominent managerial inputs form this study for teak nursery production forestry include development of standard protocols for pre-treatment, seed sowing spacing, potting media, size of the polythene bags and root trainers. The package for quality teak stump production was also standardised.ThesisItem Open Access Evaluation of biodegradable containers for seedling production in tree nurseries(Department of Silviculture and Agroforestry ,College of Forestry, Vellanikkara, 2020) Subhasmita, Parida; KAU; Kunhamu, T KA nursery trial titled ‘Evaluation of biodegradable containers for seedling production in tree nurseries’ was conducted to develop alternate eco-friendly plant container as substitute for conventional polythene bag based containers at College of Forestry, Kerala Agricultural University, Thrissur. The study involved a three month long preliminary trial to explore the efficacy of various locally available materials for use as container for tree species. Based on the preliminary trial, five better performing container types were screened for detailed nursery trial to further examine their efficiency as containers for tree seedling production. Teak (Tectona grandis) being the widely produced forest planation species in Kerala, the nursery trials were performed with teak as test crop. The locally available materials used as containers for the preliminary trial included cow dung pot, sugarcane bagasse, arecanut sheath, mud pots, bamboo splits, bamboo basket, coco pot, cloth bag, nonwoven bag, bioplastic bag and treated card board. The containers were evaluated for their durability, physical stability to management practices such as irrigation and manuring, survival percent, height and collar diameter of the teak seedlings. It was observed that the bamboo splits based containers had the highest durability and can be used for two seasons while containers made from arecanut sheath, cow dung pot, sugarcane bagasee pot, bamboo basket, bioplastic bag and cloth bag totally degraded within two months suggesting their unsuitability for tree seedling production. In general, the better container types in terms of overall seedling growth performance and physical soundness were nonwoven bag, bamboo split, coco pot, treated cardboard pot and mud pot. These five container types along with coir root trainer (CRT) supplied by Kerala Forest Department were subjected to detailed nursery trial. It was observed that considerable variability existed in seedling growth characters such as height, collar diameter, number of leaves, leaf area, number of secondary and tertiary roots, lateral root length, root length: shoot length ratio, root and shoot dry and total dry weight. Among all container types studied, nonwoven bag grown seedlings showed better growth performance followed by seedlings grown in bamboo split containers while mud pot raised seedlings showed the lowest performance during all the stages of seedling growth. The overall performance of the container types followed the order: nonwoven bag > bamboo split > coco pot > treated cardboard > Coir root trainer (CRT) > mud pot. The cost of production per seedling was Rs 8.3 for non-woven bag, Rs 60.2 for coco pot, Rs 62.0 for mud pot, Rs 11.0 for bamboo split, Rs 12.8 for treated cardboard pot and Rs 25.8 for Coir root trainer (CRT). The Benefit: Cost ratio of raising 3- month old teak seedling ranged from 0.32 – 2.45. The value was highest for seedlings raised in bamboo split pot (2.45) followed by nonwoven bag (2.41) and cardboard (1.56) while it was less than one for all the remaining container types. The trial suggest that further studies are required to develop protocols for the reinforcement of biodegradable containers for increased phys ical strength and durability.ThesisItem Open Access Floristic diversity and regeneration status of moist deciduous forests in Thrissur district, Kerala :reassessment after three decades(Department of Silviculture and Wildlife Science, College of Forestry, Vellanikkara, 2020) Abhi, Jamatia; KAU; Kunhamu, T KMoist deciduous forests in Kerala constitute one of the most degraded forest ecosystems consequent to demographic pressure and other bio- physical factors. Field investigation was carried out to study the changes in phytosociology and vegetation dynamics of Moist Deciduous Forests in selected locations in Thrissur Forest Division, Kerala during 2018-19. The primary objective of the study was to assess the changes in floristic diversity, structure and regeneration status of moist deciduous forests compared to a similar study carried out in the same locations prior to three decades. The selected three locations were Karadippara and Kalluchal in Peechi WL sanctuary and Kuthiran in Pattikkad range. The vegetation attributes subjected to detailed assessment included species diversity, density, relative density, basal area, relative basal area, relative frequency and Importance Value Index and size class distribution of vegetation. A total of 51 species have been reported in various study locations in the Moist Deciduous Forests of Thrissur Forest Division. Kalluchal represented the highest number of woody species (48 species) followed by Karadippara (37 species) and Kuthiran recording the lowest with 26 species. Tree density showed profound variation across sites with Kalluchal giving the highest number (691 stems ha-1) followed by Karadippara (688 stems ha-1) and lowest for Kuthiran (516 stems ha-1). Xylia xylocarpa contributed the maximum number of stems in all the three sites followed by Wrightia tinctoria and Holarrhena antidysentrica. Mean relative density was highest for upper stratum (44.62%) and 33.07% for the lower stratum and lowest for the middle stratum (22.30%). Karadippara, Kalluchal and Kuthiran sites represented 30, 45 and 20 species within frequency class I (within 1-20%) and there was conspicuous absence of species in the higher frequency class in all the three sites. All the three sites had similar total IVI around 300. The major share of the IVI was confined to the species in the upper stratum (58 to 60%) while the middle and lower stratum has a lower and similar trend in IVI distribution (20% each). Size class distribution of among various social l classes ii showed conspicuous absence of majority of tree species in the higher size class suggesting a skewed distribution pattern. Almost 85% of individuals in each species belonged to lower size classes (h50 and h100) which drastically declined with increase in size class. A comparison with the study in the same sites three decades back indicates variable results. There was overall improvement in species diversity and phyto-sociological attributes in the Kalluchal region particularly, the species density and regeneration patterns. However, the number of individuals in the present study at Karadippara and Kuthiran sites, especially in the lower size classes were far lower compared to the previous study implying that the regeneration patterns of many tree species have been seriously affected by the undesirable changes in the past three decades. Probably, apart from human influences, the impact of changing climate may also have affected the regeneration ecology and vegetation dynamics of the MDF forests in Thrissur District which necessitate further detailed investigation in this line.
