Jalaja Menon, SShankarprasad, K S2020-11-192020-11-192019174581https://krishikosh.egranth.ac.in/handle/1/5810155242P GThe present study was carried out at the Department of Plantation Crops andSpices, College of Horticulture, Kerala Agricultural University, Thrissur, during 2017- 2019. Seventeen bearing tamarind trees from the KAU main campus were selected for the study after preliminary survey and GPS coordinates were recorded for generating passport data. These accessions were observed for various qualitative and quantitative characters viz., tree growth habit, leaf, flower and fruit characters and biochemical parameters. Ten out of 17 selected accessions were regular yielders. Upright (47.06%), semi-spreading (41.17%) and spreading (11.77%) types of growth habits were observed. The flower initiation was observed from last week of March to the second week of May. Early flowering was noticed in accession KTI-13 and late flowering in accession KTI 6 and Acc. KTI 8. The average panicle length ranged from 7.8 cm (KTI-6) to 32 cm (KTI-17). Flowers were observed for qualitative and quantitative characters. Characters like bract colour and bracteole colour expressed higher variability among the accessions than the other characters. The bract colour varied from deep pink to pale green. Average corolla spread ranged from 2.17 cm to 3.27 cm among the selected accessions. Wide range of variability was expressed in pod characters and biochemical composition. The average pod length was highest in Acc. KTI-16 (19.22 cm). Acc. KTI- 10 recorded highest average fruit weight (26.60 g) followed by Acc. KTI-16 (23.64 g). The number of fruits per unit area of the canopy ranged from 2.83 to 9.83 among the selected accessions. Highest pulp: seed ratio was recorded in Acc. KTI-7 (1.9) while the lowest was recorded by Acc. KTI-15 (0.87). High variability was also noticed in biochemical composition of pulp like titratable acidity (7.79 to 21.94 %), TSS (55 to 70 oBrix) and Vitamin-C (11.17 mg to 18.91 mg per 100g). Accession KTI-12 recorded highest tartaric acid, Acc. KTI-3 recorded highest TSS and Acc. KTI-17 recorded highest Vitamin-C. Correlation study revealed extent of association among pod and flower characters. Highly positive and significant correlation was observed between pulp content and corolla spread. Pod length exhibited highly significant positive correlation with fruit weight. Principal component analysis of yield attributing characters like number of fruits per unit area, pod length, pod girth, pod weight, pulp weight, pulp content, seed weight and number of seed per pod grouped accessions into nine clusters. Accession KTI-13 and accession KTI-17 which were members of Cluster VII were marked as outstanding in terms of higher fruit yield per unit area of canopy and these accessions can be utilized for further breeding programmes. Five propagation methods were evaluated during four seasons under the agro climatic situation of Thrissur district. The success per cent at 90 days after grafting was highest (51.25%) for the grafting done during March-April months irrespective of propagation methods. During this period a minimum temperature of 24OC and maximum 36OC with mean monthly relative humidity 66 per cent, monthly mean rainfall of 5.2 mm and sun shine of 8.4 hours were observed. Patch budding was total failure in all the seasons studied. Among the different propagation techniques approach grafting recorded overall success of 25.63 per cent irrespective of season and success per cent in veneer grafting was on par (21.25%). Considering the interaction effect, veneer grafting recorded highest success of 70 per cent during March-April and percent success in softwood grafting (65%) and approach grafting (60%) carried out during the same period were on par with veneer grafting. Veneer grafting and softwood grafting were found superior than all other methods of propagation when grafted in the month of March-April.EnglishThesis