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ThesisItem Open Access Genetic diversity of Dimocarpus longan Lour., in Southern Western Ghats(Department of Forest Biology and Tree Improvement,College of Forestry, Vellanikkara, 2022) Devika, P S; KAU; Manju Elizabeth, PLongan (Dimocarpus longan Lour.), is an important commercially cultivated fruit tree, belonging to the family Sapindaceae. It is commonly known as dragon-eye. In Kerala, it is known by the names chempoovam, mullai etc. It is widely cultivatedin many Asian countries like China, Thailand, and Taiwan etc. Recently many other countries including India, Sri Lanka etc. have started cultivating longan tree as a commercial fruit tree. Longan is used as a traditional medicine in China due to its high medicinal and nutraceutical value. The global demand for longan fruit has hiked rapidly due to its sweet taste and nutritional value. Fruit consist of a white edible juicy aril which is surrounded by a leathery pericarp. The fruit is rich in various bioactive polyphenols, vitamin C, volatile compounds, minerals, amino acids, proteins, fats, carbohydrates etc. Longan leaf, fruit pericarp, seed and pulp were used for extracting various polyphenols. Extracts from various parts of longan have shown pharmaceutical properties like antioxidance, anti-tyrosinase, anti-cancerous, anti-glycated, immunomodulatory activity, antihypertensive etc. Thus the importance of fruit can also be emphasized due to its richness in nutritional value. The longan tree is a subtropical fruit tree native to the southern regions of China and Indo-Burma. D. longan is indigenous to India's Western Ghats, ranging from Konkan to Tinnevelly. Other distributions in India include Eastern Bengal and Western Peninsular regions. In the Western Ghats region of Kerala, longan is a species widely distributed in evergreen forests. There is a small distribution in the semi-evergreen forests of Kerala as well. The diversity of indigenous longan populations in Western Ghats has never been studied before. In this study, morphological and genetic diversity of longan populations from six different locations in the Western Ghats regions of Kerala were selected. Among these six locations, three were located in the north of Palghat gap and three were in the South ii of Palghat gap. Morphological parameters like crown shape, branching pattern, tree height, tree girth, leaf length and leaf width was considered for studying the morphological diversity. Results from morphological traits revealed that the population from Meppadi region from north of Palghat gap stood different from other longan populations. Cluster analysis conducted using UGPMA method based on the morphological traits showed that population from Mankulam was closely related to the Meppadi population. The populations from six locations were divided into two major clusters. ISSR primers were used to investigate the genetic diversity existing among the six populations. 15 ISSR primers screened from total of 19 primers were used to amplify the DNA sample from different longan populations. Average polymorphism rate of 69.51% was observed. Matrix data was obtained and hierarchical dendrogram was produced using UGPMA method in NTsys pc 2.02 and DARwin software which clusters the populations into two major groups. Jaccard’s dissimilarity index was calculated using R software and the values ranged from 0.00 to 0.51. Genetic relation existing between the natural populations of longan in Kerala, cultivated longan cultivars and litchi were identified. Cluster analysis using UGPMA method pooled different populations into four major clusters and study proved that litchi is genetically more related to the cultivated longan variety rather than the wild populations. This is the first report on the molecular characterization of D. longan from Western Ghats regions in India. The results from this research study can provide valuable information to distinguish, classify and identify the origin of longan populations in India and can be applied for future breeding programs.ThesisItem Embargo Soil nutrient dynamics in a second rotation monocropped teak plantations(Department of Forest Biology and Tree Improvement, College of Forestry, Vellanikkara, 2022) Santhosh, D T; KAU; Santhoshkumar, A VTeak is considered the most valuable tropical timber species and is known as the "King of Timber". Kerala has 76,710 ha of pure teak plantation and 14,440 ha of teak plus softwood planting, accounting for 49.08 and 9.24 percent of the state's total plantation area, respectively. Kerala's teak plantations productivity has been declining and a large-scale drop in teak plantation productivity in the replanted teak regions, referred to as ‘Second rotation decline’ is being observed. In this context, a field study on “Soil nutrient dynamics in a second rotation monocropped teak plantations” was conducted in selected plantations from Thrissur and Chalakkudy Forest Divisions to investigate the quantity and intensity of soil nutrients among second rotation teak plantations. The study site was divided into five age classes (0-10, 10-20, 20-30, 30-40 and 40-50 years) and 6 replications (sample plots) were laid out in each age class forming a total of 30 sample plots (6 sample plots x 5 age classes). Sample plots of size 24m x 24m were laid randomly and total tree height and girth at breast height were measured in the field. Surface soil (0-30cm) samples were collected from each plot. Teak foliage sampling was done by collecting the index leaf (second fully opened leaf from the bud). Ground vegetation sampling was carried out by harvesting all vegetation from randomly laid out 1m x 1m plots from each sample unit. Soil sampling was also carried out from open barren lands from both the forest divisions. The collected soil was analysed for physical properties like particle size distribution/texture and chemical properties like soil pH, CEC, exchangeable bases, extractable acidity, organic carbon, quantity and intensity factors of N, P, K, Ca, Mg, S, Na, Fe, Zn, Cu, Mn, Al, Ni, Cd, Pb and also the critical limits with reference to teak. Quantity of C, N, P and K were estimated from teak foliage and ground vegetation following standard procedures. The results showed that among the plantations studied in Thrissur and Chalakudy divisions, there were differences in terms of soil chemical properties in 100 plantations of different age classes. However, definite pattern of concentration of elements with respect to the age of the plantations was lacking. The intensity factors of nutrients too showed no pattern or trend with reference to the age of the teak plantations. The variation in ion concentration in soil solution was not influenced by the quantity or labile pool of the element. The soils from teak plantations were observed to have more concentration of nutrients compared to barren land. All the observed soil parameters were well within the range required for the optimal growth of teak. However, there was also variation in terms of the concentration of the elements. Attempts to relate soil parameters to site productivity yielded no relevant associations, implying that the decline in productivity may be due to poor management rather than nutrient depletion. There was significant management inconsistency among the plantations, which significantly influenced the potential utilization of site resources for optimal teak development. Significant variation in the content of C, N, P and K were observed in teak foliage of various age classes. A decrease in N, P, and K content was observed in the foliage with an increase in age. The content of C, N, P and K in the ground vegetation samples of different age classes showed no pattern in trend with respect to the age of the teak plantations. Further extensive studies on the soils from teak plantations in the state in terms of ion activity to obtain better knowledge in terms of nutrient deficiency and toxicity with a particular focus on improving productivity of teak plantations is also required. The results of this study also point to an imperative necessity to study other factors apart from soil that affect teak productivity.ThesisItem Open Access Progeny testing and genetic diversity analysis in plus trees of Melia dubia Cav.(Department of Forest Biology and Tree Improvement, College of Forestry, Vellanikkara, 2022) Shifin S, Ravuther; KAU; Binu N, KamalolbhavanThe present study titled “Progeny testing and genetic diversity analysis in plus trees of Melia dubia Cav.” was carried out from 2020 to 2021 with the objective of progeny evaluation in 25 half sib plus trees identified from different part of Kerala, by studying the growth performance of its seed progeny planted at college of forestry germplasm field. The study also includes exploring the genetic diversity of these 25 plus tree seed progenies along with analysing the caryophyllene content, one of the economically important phytochemical compounds present in M. dubia. The plus tree seed progeny differed significantly in morphological traits like height, collar girth, volume and physiological parameters like photosynthetic and transpiration rate, stomatal conductance, chlorophyll content and relative water content. The progeny FCV-MD-03 of Tholpetty in Wayanad district performed better in growth parameters viz., height (5.61 m), collar girth (0.42 m) and tree volume of (0.017 m3 ). The variability study indicated that the morphological trait (volume) and physiological trait (stomatal conductance) exhibited higher PCV and GCV. From the heritability estimation it was observed that the most heritable morphological trait was collar girth followed by the plant height. For the physiological parameter, transpiration rate (0.91) was the most heritable trait followed by the chlorophyll content. These morphological and physiological traits were positively correlated implicating the significance of physiological parameters as source to identify better progeny. Path analysis on morphological trait has showed that the collar girth had the highest positive direct effect on the plant volume. Genetic variation study in 25 plus tree progenies using ISSR primer produced 164 amplicons which estimates viz., percentage of polymorphism (68%), polymorphism information content (0.70 to 0.83), Nei’s gene diversity (31%). The dendrogram obtained by using UPGMA classified the 25 accession of M. dubia into 2 distinct clusters. Cluster I constitute population from Wayanad and the rest of the 136 population in cluster II. Based on the genetic variation observed, superior seed sources can be identified and tree improvement programme could be developed for the conservation and further development of M. dubia. Standardization of HPLC for the quantification of caryophyllene phytochemical in M dubia was studied. Significant variation was observed for the total caryophyllene content for the different accession of M dubia seed progeny. The maximum quantity was observed in FCV-MD-08 (16.4 %) of Pothundy in Palghat district followed by FCV-MD-3 of Tholpetty in Wayanad.ThesisItem Open Access Selection for drought tolerance and wood quality traits from selected accessions of Tectona grandis Linn f.(Department of Forest Biology and Tree Improvement, College of Forestry, Vellanikkara, 2020) Anjana, C B; KAU; Santhoshkumar, A VTeak (Tectona grandis Linn. f.) is an important hardwood timber in the tropic. Most teak-growing countries are now performing tree improvement programs. It mainly aimed at achieving superior growth characteristics. These may have indirect effect on wood properties. So it is essential to include wood quality traits in breeding of teak. As teak requires long nursery period which extends to almost one year and any decline in moisture during this period may cause decline in initial growth and may eventually lead to death of teak.Asstated,mostofthebreedingactivitiesthathavebeendoneonteakinvolvedselecting plustreesbasedonlyonquantitativeandqualitativetraits.Tillnow,veryfewworkwasdone on screening teak for drought tolerance. The study is being conducted at the teak provenance trial plantation established in Livestockresearchstation,Thiruvizhamkunnu.30accessionsofteakwereplantedincompact family block design with 3 progenies each, replicated five times. Out of 30 accessions, eight were completely absent in the field. From the remaining 22 accessions, three were discarded due to the lack of enough number of progenies (minimum 2) per accession. So the 19 accessions were used for the further studies. Growth characters and wood quality traits were observed among these accessions from thefield. Growth parameters like height and girth showed significant variations among 19 provenances.Variationofheightwasintherangeof9.57m(A5)to17.97m(A2).Thevariation in the girth at breast height was in the range of 31.75cm (A5) to 86.07(A29). PPD and SWV showedsignificantvariationsamong19provenances.AccessionsA2,A29,A21,A20,A1,A3 andA22showedbettergrowthparameters.ThevalueforPPDrangefrom20.25mm(A1,A23) to 24.25mm (A20). The value for SWV ranged from 3535 ms-1 (A29) to 4360 ms-1(A30). Specific gravity for the different accessions was calculated from the regression equationusing PPD. Specific gravity range from 0.32 (A20) to 0.44 (A1, A23). Among the accessions, A23, A17, A28, A19, A18, A21 and A22 showed better wood qualitytraits. Eighteen trees belonging to eighteen accessions were then selected using comparison method. These trees were then vegetatively propagated through stem cuttings for further studies. These accessions were then screened for drought tolerance by studying physiological changes in response to imposed drought stress in three stages viz. normal, stress and regain. Kruskal Wallis test showed significant variation among physiological parameters during these three stages of drought. A significant reduction in stomatal conductance, transpirationrate, photosynthetic rate, relative water content, chlorophyll a and chlorophyll b content, total chlorophyll content, membrane stability index, chlorophyll stability index as compared to normal growing conditions among the accessions of teak. A significant increase was observed in the canopy air temperature difference among the accession. A hierarchical cluster analysis was carried out for physiological parameters of the accessionsduringdrought.Theaccessionswhichperformedwellduringdroughtweregrouped in cluster IV. The accessions belonging to this cluster was A21, A6 and A24. During drought, higher values for chlorophyll stability index, membrane stability index, chlorophyll a and chlorophyll b content, total chlorophyll content, relative water content and the photosynthetic rate was observed for A21. In addition to that highest value for stomatal conductance and transpiration was recorded in A21 and A6. Chlorophyll fluorescence was observed highest in A21, A24, A5 and A6. Among the accessions, the lowest value for the canopy air temperature difference was observed inA21. Duringregainrecoveryinphysiologicalcharacterswasobservedamongtheaccessions. A21 showed higher values for physiological parameters like chlorophyll stability index, membrane stability index, chlorophyll a and b content, total chlorophyll content, chlorophyll fluorescence, relative water conductance, transpiration and stomatal conductance. The photosynthetic rate was observed highest in A21, A6, A5 and A24. A13 and A17 found to be least recovered during drought because of prolonged damage to physiological process after imposeddrought.Itcanbeconcludedfromtheaboveresultsthatconsiderablevariationexisted among the teak accessions for wood properties and growth characters. In drought tolerance studies significant variation among the accessions were also observed. A21 is found to be drought tolerant compared with otheraccessions.ThesisItem Unknown Diversity assessment and selection of candidate plus trees of Ailanthus triphysa (Dennst.) Alston in selected districts of northern Kerala(Department of Forest Biology and Tree Improvement, College of Forestry, Vellanikkara, 2020) Jes, Lalnunpuia; KAU; Santhoshkumar, A VMatti (Ailanthus triphysa [Dennst.] Alston), belonging to the family Simaroubaceae is a medium to tall evergreen rainforest tree. It is one of the most important and extensively used trees for making match splints in India. The study attempted to determine the diversity and select candidate plus trees from selected districts of Northern Kerala and to evaluate their progeny. Thirty candidate plus trees were selected based on baseline regression of trunk volume to crown volume combined with scoring for qualitative characters. The tree height, GBH, crown diameter and clear bole height of the plus trees varied from 20 m to 37 m, 0.69 m to 2.11 m, 3.5 m and 9.75 m and 7 m to 24 m respectively. The thirty candidate plus trees were grouped into nine clusters through cluster analysis. Cluster I had a maximum number of CPTs with 15 accessions, whereas the least number observed for cluster VII, VIII and IX respectively. Clusters with only one plus tree can either possess superior or inferior quality among the plus trees. The clustering pattern revealed that plus trees from the same geographic sources were grouped into different clusters, while plus trees from different geographic sources were grouped into the same clusters. The highest intra and inter cluster was observed on cluster I (2.07) and cluster III and IV (8.91). This indicates there was greater genetic distance within and between the clusters. Seedling biometric observations for different morphological and physiological characters showed significant differences except for the height of the seedlings. The seedlings height, collar diameter, the number of leaves and biovolume ranged from 8.73 cm (FCV-AT-02) to 11.2 cm (FCV-AT-01), 0.14 mm (FCV-AT-02) to 0.25mm (FCV-AT-16), 4.33 (FCV-AT-02) to 6.53 (FCV-AT-20) and 0.12 cm3 (FCV-AT-02) to 0.32 cm3 (FCV-AT-16). The progenies FCV-AT-21, FCV-AT-33, FCV-AT-36, FCV-AT-37, FCV-AT-39 and FCV-AT-40 were found superior based on overall mean performance of the morphological characters. Hence, seeds of these CPTs can be used in immediate field planting operations. The genetic analysis of the causes of variation for the morphological and physiological traits was studied. The highest phenotypic and genotypic coefficients ii of variation were observed on the character biovolume. For all the characters studied, the phenotypic coefficient of variation was higher than the genotypic coefficient of variations indicating that there were non-additive effects. High heritability coupled with a genetic gain was observed in the number of leaves and collar diameter. Similarly, heritability was high for all the physiological traits with an adequate genotypic variation that can help in the further improvement programme. The correlation studies on morphological and physiological studies showed that positive correlation was observed in the seedlings height and collar diameter of the CPTs. The relation with collar diameter and biovolume, collar diameter and stomatal conductance, biovolume and stomatal conductance of the CPTs were also found positive. A positive correlation was also recorded on the plus trees selected on the characters photosynthesis and transpiration and stomatal conductance and leaf temperature. It can be concluded from the study that considerable morpho-physiological variations exist in selected candidate plus trees of Ailanthus triphysa. These results could help in the future breeding programme as well as efficient management of the trees.ThesisItem Open Access Diversity analysis and selection of candidate plus trees of Swietenia macrophylla from selected districts of north Kerala(Department of Forest Biology and Tree Improvement, College of Forestry, Vellanikkara, 2020) Aleena Thomas, Moor; KAU; Santhoshkumar, A VThesisItem Open Access Drought response in plus trees of teak (Tectona grandis Linn.f.) provenances of Kerala(Department of Forest biology and tree improvement, Vellanikkara, 2020) Mohammed Ali Eltoum, Hassan; KAU; Santhoshkuamar, A VA study on ‘Drought response in plus trees of teak (Tectona grandis Linn. f.) provenances of Kerala’ was conducted in College of Forestry, Vellanikkara during 2018-2019 to evaluate variability in seedling biometric, physiological and biochemical characters of plant during drought stress and drought recovery. Drought stress was induced by withholding water till leaves exhibited symptoms of wilting. Plantlets were exposed to two consecutive drought treatments with an intervening period of stress relief through rehydration. Seedling vigor was screened at six months. No variability was present in morphometric characters like height, diameter, number of leaves and branches. After inducing drought stress, growth parameters slowed down in all accessions between plus trees. Induction of drought resulted in reduction in most of the physiological parameters of the plantlets of teak plus tree accessions. Relative water content, photosynthetic rate, stomatal conductance, transpiration rate, chlorophyll a, chlorophyll b, total chlorophyll and chlorophyll stability index showed reduction. However, under drought stress, plantlets showed increased of canopy air temperature differences and cell membrane stability index. Most of biochemical parameters like free amino acid, proline, glycine betaine, total soluble sugar, super oxide dismutase, peroxidase and malondialdehyde increased after inducing drought. However, total soluble protein and nitrate decreased under drought induction. After rehydration, most of these physiological and biochemical parameters rapidly returned to the level of normal irrigated condition. The stomatal conductance was only differed in the accessions before stress was induced. However, after stress, it was found that accessions differed in stomatal conductance, photosynthetic pigments and total chlorophyll content. In drought recovery, there was no variation in physiological parameters among accessions. Variability on biochemical characters were observed in nitrate reductase, free amino acid, proline and peroxidase among accessions during pre-stress stage, while in drought stress it was observed that proline, super oxide dismutase, peroxidase and 139 malondialdehyde differed among accession. In drought recovery, characters such as nitrate reductase, free amino acid, proline and peroxidase showed variability. Correlation studies showed that among the physiological and biochemical character only chlorophyll a, chlorophyll b and total chlorophyll showed positive correlation with the number of leaves during drought stress, while in recovery, positive correlation was shown by super oxide dismutase, chlorophyll a, chlorophyll b and total chlorophyll content and negative correlation was observed in photosynthetic rate, transpiration, relative water content and stomatal conductance. Hierarchical cluster analysis was done for the eleven accessions based on the Euclidian squared distance. During drought stress, the accessions grouped into five clusters; cluster III possesses four of accessions whereas the least number observed for the cluster V. In recovery, it was grouped into seven clusters; cluster VII had three accessions, while only one accession was present in cluster I, IV, V and VI. First two components of principle component analysis during drought stress accounted for 41.9 per cent of the total variability, which was mainly contributed positively by relative water content, nitrate reductase, free amino acid, proline and malondialdehyde. In drought recovery, first two components of PCA together accounted for 53.2 per cent of the total variability, which was mainly contributed positively by photosynthetic rate, stomatal conductance, transpiration rate, chlorophyll stability index, glycine betaine and malondiadehyde. Selection index were worked out to select accession tolerant to drought stress and recovery based on biochemical parameter and chlorophyll content using first principle component as index. It was found that KFRI T55 was most tolerant and quickest to recover after reliving stress among accession. It can be concluded from the results that physiological and biochemical variations exist in teak plus tree accessions. These results could be useful in selection of drought tolerantThesisItem Open Access Evaluation of wood quality of selected tropical pines raised in the high ranges of Kerala, for pulp and paper making(Department of Tree Physiology and Breeding,College of forestry,Vellanikkara, 2010) Ajayghosh, V; KAU; Anoop, E VA study entitled “Evaluation of wood quality of selected tropical pines raised in the high ranges of Kerala, for pulp and paper making” was conducted in the College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur during the period 2008-2010. The objective of the study was to evaluate the wood quality of Pinus caribaea Morelet, Pinus patula Schl. et Cham. and Pinus oocarpa Schiede grown in research trials of the Kerala forest department in the high ranges of Idukki district of Kerala. Increment core wood samples were collected at breast height from trees, selected at random, from each plot representing each species belonging to different age levels. These samples were then subjected to intensive investigations to find out radial variation (pith, middle and periphery), species variation and influence of age on different wood physical, anatomical and chemical properties. The study revealed that many of the characters studied were influenced by species and age interaction. Radial variation was also found to have significant difference within the species for characters studied. As a whole, under the present climatic condition P.caribaea was found to perform better with wood properties within the accepted range suitable for pulping and paper making. On the other hand, P. patula and P. oocarpa were also found to be promising species for pulping and papermaking with better derived fiber ratios. However, P. oocarpa had specific gravity value slightly more than that is recommended for pulp and paper making. Studies on chemical composition revealed that P. ooccarpa had better performance with higher cellulose and lower lignin content. So what needs to be determined is the relationship, if any, between wood and tracheid properties of these species and the products which can be manufactured from this renewable resource. For this, more extensive study is needed for which the results of this study could be used as a base line data for future tree improvement aspects of these species with reference to wood quality and to bring out their potential utility for future afforestation programmes and timber utility.ThesisItem Open Access Morphological and biochemical diversity assessment of Garcinia indica(Thouars) choisy germplasm(Department of Forest Biology and Tree Improvement, College of Forestry,Vellanikkara, 2019) Raveena Kapatia, KAU; Santhoshkumar, A VA study on ^Morphological and biochemical diversity assessment of Garcinia indica (Thouars) Choisy germplasm' was conducted to find out variations in G. indica germplasm maintained at NBPGR Regional station, Thrissur. The study attempted to evaluate variability in general tree characters, flower, fhiit, biochemical characters and physio-chemical properties of butter. It was observed that large variability was present in morphometric characters like height, GBH and height of first branch, whereas characters like canopy shape and branching habit did not show much variations. In comparison to the general tree characters, leaf and flower characters showed less variability. Among all the leaf characters studied, petiole length showed largest variation (CV=20.2 percent). In case of flower characters, maximum variability was observed in pedicel length. Variability was also observed in the timing of flowering, which ranged from October to January. Variability study on fruit characters like fruit weight, rind weight and number of fruits showed significant variations. Yield ranged from 220 to 1050 fruits per tree. Fruit colour did not show much variations, mainly being dark purple and red. Primary metabolites like carbohydrates, proteins and crude fat showed considerable variability, while it was observed to be comparatively low in TSS and reducing sugar. Variability was also observed in secondary metabolites like phenols (CV = 29.1 percent) and ilavanoids (CV = 17.9 percent). It was observed that Hydroxy citric acid was present in large quantity in fruit rind, average being 36.5 g/IOOg. The variability study on minerals like Ca, Na, Mg, K and P revealed that K was present in the largest quantity, followed by Mg. Maximum variability was observed in P content (CV=24.4 percent) while minimum in K content (CV =9.5 percent). The average vitamin C content was estimated to be 37.17 mg/lOOg and CV being 27.6 percent. Variabilit>' study on physio- chemical properties of kokum butter showed that on an average 30.55 percent of butter (CV=12 percent) was obtained from the seeds. Less variability was present in the melting and pour point of butter. Chemical properties of butter like saponification value, acid value and iodine value also showed less variability.