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ThesisItem Open Access Litter dynamics of selected multipurpose tree species used as pepper standards(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2005) Bino George; KAU; Kunhamu, T KA field trial was conducted at Livestock Research Station, Thiruvazhamkunnu, Kerala during August 2002 - August 2003 to characterize the litter dynamics and nutrient flux associated with seven MPTS used as support for black pepper. The study covered quantification of litter production, litter decomposition, nutrient release pattern through litter route and the changes in soil properties and site productivity in terms of pepper yield. The pepper support tree species under study included, Casuarina equisetifolia J.R. & G. Forst, Macaranga peltata (Roxb) M.-A, Ailanthus triphysa (Dennst.) Alston, Artocarpus heterophyllus (Linn), Acacia auriculiformis (A. Cunn.) ex Benth, Grevillea robusta (A. Cunn.) ex R. Br. The experiment was superimposed on a pre-existing, fourteen- year- old pepper stand in a Randomized Block Design with three replications. Generally, moderate levels of litter production has been shown by different pepper support trees under investigation. Annual litter yield was maximum for Artocarpus (4653.63 kg ha-1) and Macaranga (4550.88 kg ha-1), while Ailanthus (2221.25 kg ha-1) yielded minimum. Nutrient level in litterfall varied between species. Maximum N content was associated with nitrogen fixing trees such as Acacia and Casuarina. The leaf litter decomposition rate was generally faster for all the species with almost 90 per cent mass loss within three months. Artocarpus showed faster rate of litter decomposition while Macaranga and Ailanthus were relatively slow decomposers. Unprecedented heavy mass loss was registered by Casuarina, Grevillea and Acacia from their litterbags owing to physical nature of the litter. All the selected tree species showed a characteristic biphasic pattern of litter decomposition. Decay coefficients ranged from 0.73 (Casuarina) to 0.19 (Macaranga). The exponential equations relating mass loss over time were worked out for all the species. The lignin content of the leaf litter was found to excerpt negative influence on the rate of litter decomposition. The general order of nutrient in terms of their releasing capacity from the decomposing litter was K>P>N. Acacia and Artocarpus registered faster rate of nutrient accretion. Changes in soil properties such as moisture content, pH and bulk density was marginal on account of the presence of tree species. Leguminous species like Acacia was found to improve the soil N content. Maximum rainfall interception was attributed to Artocarpus followed by Macaranga. The yield of pepper in terms of dry berry weight was maximum for Acacia (2.56 t ha-1) and Artocarpus (1.91 t ha-1). Better physical suitability, high lopped out turn and nutrient turnover potential suggest these species as ideal candidates for trailing pepper. However, the general reduction in soil physical and chemical properties and reduction in the yield of black pepper for each standard over years suggest a declining trend in the productivity of this system, probably induced by the ageing of the stand as well as the heavy management practice followed.ThesisItem Open Access Effect of seed size on the germination and seedling performance of teak (Tectona grantis Linn. f.)(Department of Silviculture & Agroforestry, College of Forestry, Vellanikkara, 2004) Jijeesh, C M; KAU; Sudhakara, KA detailed study was conducted at the College of Forestry, Vellanikkara to investigate the effect of seed size on seed characters and germination vigour and the effect of seed size and time of germination on seedling performance of teak (Tectona grandis Linn.f.) during 2001-2003. Most of the fruits were belonging the grades between 9 to 18 mm. 12-15 mm size grade recorded the highest proportion by number as well as the weight per kg of the sample lot compared to 15-18 mm, 9-12 mm and 6-9 mm grades. Size, volume and weight of the individual seeds not differed between the plantations studied. The average emptiness value of the seeds decreased with the increase in seed size. The number of empty, one, two, three and four 'true seeded' seeds increased with increase in seed size grade. The crude oil content of the true seeds ranged between 42 to 33 per cent by weight and that of soluble and total carbohydrate content ranged from 6.42 to 5.12 and 10.72 to 9.61 per cent by weight and these were found to increase with increase in size grade. The insoluble carbohydrate content of 'true seeds' was ranging from 4.5 to 3.8 per cent by weight and it varied significantly between the plantations and Cherupuzha plantation recorded the maximum amount. Protein content of the seeds ranged from 3.7 to 3.6 per cent by weight and it did not vary significantly between the plantations as well as size grades. Poly acrylamide gel electrophoresis of proteins at ph 7 gave similar banding pattern (two bands with Rm values 0.09 and 0.19) for different size grades in all the plantations. Storage of the seeds for one year significantly reduced the germination Size grade of the seeds used to conduct the nursery studies significantly influenced the germination percentage of the seeds as well as the vigour index of the seedlings. The effect of seed size grade and time of germination on seedling characters was significant at all stages of growth of the seedlings with the exception of taproot length, specific leaf area and chlorophyll a content of the seedlings. The seedlings belonging to 15-18 mm grade seeds recorded largest height, collar diameter, internodal length, length of longest lateral roots, leaf area, number of lateral roots, stem dry weight and chlorophyll b and total chlorophyll content at different stages of growth. Seedlings belonging to 9-12 mm seed grade recorded the lowest values of these characters. The leaf, stem and total dry weight of the seedlings at 270 and 360 DAP were found to increase with the increase in size grade of the seeds. Seedlings belonging to 9-12 mm grade showed higher RGR and NAR values compared to that of the seedlings belonging to 15-18 mm and 9-12 mm seed grades in first to fourth week germinants. There was no definite pattern in variation of number of leaves, and root:shoot ratio among the of the seedlings due to size grade of the seeds. With regards to time of germination of the seeds, seedlings obtained from the first week germinants recorded the largest height, internodal length, collar diameter and leaf area at all the stages of growth. Other characters did not show any definite trend due to time of germination. Significant differences due to seed size was absent in all the attributes related to the growth potential of the stumps prepared from 180 days old seedlings. However, the effect of time of germination of the stumps was significant in the number of lateral and tertiary roots per stump and length of the first, second and third longest lateral root. Dry weight of the lateral roots was found to increase with the increase in seed size grade of the stumps obtained from 360 days old seedlings. With regards to time of germination, the stumps obtained from the first to fourth week germinants varied significantly in the number of sprout, length of the second sprout, number of leaves, lateral and tertiary roots per stump and length of the first, second and third longest lateral roots.ThesisItem Open Access Phenology and regeneration of shola-grassland edge tree species(Department of Silviculture and Agroforestry, College of Forestry, Vellanikkara, 2003) Nanaya, K M; KAU; Sudhakara, KA study was undertaken in Mangaladevi, Periyar Tiger Reserve, and College of Forestry, Kerala Agricultural University, Vellanikkara, during the period 2001-2002 keeping in mind that edge species are better suited for the afforestation of the depleting shola forest than going for exotic species or any of the interior species. The specific objectives of this research project were to study and find out important edge tree species in the shola forest, to study the phenological aspects of these selected edge tree species and to study the artificial regeneration possibilities of these selected edge tree species. Phytosociological analysis revealed 47 species of trees along the shola- grassland edge in an area of 5950m2 across 27 families. Species with highest Relative Importance Value Index (RIVI) were Psychotria elongata (15.22). Ligustrum robustum (11.33), Maesa indica (10.53), Litsea wightiana (7.39), and Vernonia arborea (5.27). The total density of the Shola forest edge was 1703 individuals ha-1. Psychotria elongata had the highest density of 588 individual ha-1 followed by Maesa indica, Ligustrum robustum and Litsea wightiana which were subjected to further phenological observations to determine their phenological patterns. Leaf, flower and fruit phenological patterns followed by these selected edge tree species during the period between July 2001 and June 2002 have been presented in detail. Data obtained from the phytosociological analysis were used to derive various diversity indices of the arborescent flora of these forests have also been presented. Results of maturity, storage and artificial regeneration studies conducted on Psychotria elongata, Ligustrum robustum and Maesa indica have also been presented. Maturity studies reveal that the seeds of Psychotria elongata and Ligustrum robustum mature in the month of January while, the seeds of Maesa indica was mature during the months of September to January. Results of storage studies on these species suggest that storage of Ligustrum robustum and Psychotria elongata is not advisable while, storage of Maesa indica is beneficial as it shows a ripening period after collection. The study revealed the lower diversity along the edges of the shola forests of Mangaladevi. This is of great concern and immediate steps need to be taken to stop further degradation of these forests and rejuvenate them. The results available about the phenology, maturity and storage studies of these species can help in further studies, which can lead to use of native edge tree species for enrichment of these depleting forests.