Thumbnail Image

Theses

Browse

2012 - 20143
Reset filters
Subject: Others × Author: KAU × End date: 2015 × Start date: 2011 × Type: Thesis ×
Reset filters

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    ThesisItemOpen Access
    Identification of paprika (Capsicum annuum L) genotype(s) for yield and quality characters
    (Department of Olericulture, College of Agriculture,Vellayani, 2012) Lekshmi, S L; KAU; Sreelathakumary, I
    The experiment entitled “Identification of paprika (Capsicum annuum L.) genotype(s) for yield and quality characters” was conducted at the Department of Olericultue, College of Agriculture, Vellayani, during the period 2011-2012. The study envisaged assessment of genetic variability in paprika and to study the influence of harvest maturity on quality parameters. Fifty three accessions of paprika were collected from different parts of country and grown in the field in RBD with three replications. The analysis of variance revealed highly significant differences among the 53 accessions of paprika for all the characters studied viz., plant height, primary branches, days to flowering, days to maturity, node to first flower, height of node to first flower, fruit length, fruit girth, fruit weight, fruits per plant, yield per plant, pedicel length, fruit: pedicel ratio, flesh thickness, seeds per fruit, flesh: seed ratio, driage, oleoresin, colour, ascorbic acid, capsaicin, bacterial wilt and leaf curl virus incidence. Among the accessions CA 6 recorded highest yield per plant (776.12 g) and CA 12 recorded maximum number of fruits (265.33). Fruit weight was highest in CA 47 (13.43 g). High phenotypic coefficient of variation and genotypic coefficient of variation were observed for yield per plant, fruits per plant, fruit weight and primary branches per plant. High heritability and high genetic advance also observed for these characters. The path analysis revealed that fruit weight, fruits per plant, plant height and primary branches had direct effect on yield per plant. Correlation and path analysis revealed that fruits per plant is the primary component as evident from the positive correlation as well as high direct and indirect effect on yield. Maximum oleoresin content was observed in CA 7 followed by CA 29 and CA 37. CA 2 recorded a high color value with pungency and CA 37 recorded a high colour with low pungency. CA 38 recorded maximum ascorbic acid content. CA 34 and CA 40 had the minimum pungency and CA 10 recorded the maximum pungency. Bacterial wilt and leaf curl virus incidence among the 53 accessions were studied. CA 33, CA 34, CA 35 and CA 47 recorded less incidence of both diseases. Based on Mahalanobis D2 analysis the current genotypes were grouped into four clusters. Cluster I was the largest with 34 accessions, followed by cluster IV with 15 accessions and cluster II with three accessions. Cluster III had only one accession. In the present study maximum divergence was observed between clusters II and IV as shown by their high intercluster distance. The minimum intercluster distance observed between the clusters I and II indicated a close relationship among the accessions. Based on selection index including both quantitative and qualitative characters CA 34 (Local, Dharwad) was ranked first followed by CA 7, CA 6, CA 33 and CA 35. The accessions were genetically catalogued and the result revealed distinct variations among the accessions for vegetative, inflorescence, fruit, seed and quality characters. Quality characters showed significant differences among the accessions and harvest maturity stages. Oleoresin, colour and capsaicin content in the paprika fruits were found to increase as the age of the fruits increased. Ascorbic acid content in the fruits increased from turning stage to red ripe and then declined. On the basis of the present study the high yielding accessions can be grouped into low pungent and pungent paprika. Among the low pungent, high yielding accessions CA 34, CA 33 and CA 35 recorded high colour value also. CA 6 and CA 7 are promising high yielding pungent paprika accessions. These accessions can be utilized for further crop improvement programmes.
  • Thumbnail Image
    ThesisItemOpen Access
    Wood property variation in selected clones of casuarina equisetifolia L. grown in karur district;Tamil Nadu for pulp and paper making
    (Department of Wood Science, College of Forestry,Vellanikkara, 2013) Vishnu, R; KAU; Anoop, E V
    Variation in wood physical (specific gravity) anatomical (vessel and ray morphology) and chemical (cellulose and lignin per cent ) properties of 46 casuarina (casuarina equisetifolia L) clones grown in Karur district, Tamil Nadu was studied to assess their suitability for pulp and paper making. Transverse dics collected from billets were converted to smaller specimens for undertaking studies on wood physical, chemical and anatomical properties. Estimation of specific gravity was undertaken using a precision balance and fibre morphology was studied using an image analysis system. Cellulose and lignin were estimated using standard procedures. Nested analysis of variance was carried out to find out inter and intra clonal variation of clones. All the physical and anatomical properties except fibre lumen width, runkel ratio, rigidity coefficient , flexibility coefficient and shape factor, showed significant difference between clones. Within clone variation was also significant for all the physical and anatomical parameters except specific gravity (oven dry). In order to assess the suitability of clones for pulp and paper making, specific gravity (oven dry), fibre length, Runkel ratio, shape factor, slenderness ratio, flexibility coefficient , rigidity coefficient , and cellulose and lignin content of clones were found to be within the acceptable range for pulp and paper making , clones were grouped to four clusters by carrying out hierarchical cluster analysis on the basis of all physical, anatomical, chemical and growth parameters. Cluster 4 (one clone) and cluster 2 (11 clones) were found to be better for pulp and paper making in comparison to other clusters.
  • Thumbnail Image
    ThesisItemOpen Access
    Enhancement of storage life of synthetic seeds of cocoa(Theobroma Cacao L.) through germination inhibition, desiccation and low temperature treatments
    (Department of Tree Physiology and breeding, College of forestry,Vellanikkara, 2014) Mobin, K M; KAU; Santhoshkumar, A V
    The research work entitled “Enhancement of storage life of synthetic seeds of cocoa (Theobroma cacao L.) through germination inhibition, desiccation and low temperature treatments” was carried out at Plant Tissue Culture Laboratory, College of Forestry, Vellanikkara, during the period 2012-2014. The objectives of the research work were to enhance the longevity of synthetic cocoa seeds through the application of different concentrations of chemical inhibitors/osmotica, desiccation at different RH for varying durations and low temperature treatment under refrigerated conditions and hence to prepare a storage protocol for synthetic cocoa seed. Synthetic seeds using calcium alginate encapsulation technique were prepared from embryonic axes of cocoa containing ¼ cotyledon. The experiments revealed that, presence of different chemical inhibitors in storage medium significantly influenced radicle emergence of synthetic seeds of cocoa. ABA at 10 -3 M and 10 -4 M level did not inhibit the radicle emergence of synthetic cocoa seeds and seed mortality were observed by 20 th and 25 th day respectively in both the concentrations. All synthetic seeds stored in higher concentrations of coumarin (10 -2 M) and CCC (1 M) containing ½ MS basal medium were found mortal on 10 th and 15 th day respectively. The presence of lower levels of coumarin (10 -3 M) or CCC (10 -1 M) in the storage medium helped to extend the longevity of synthetic cocoa seeds for 60 days without complete loss of viability. The combination of 10 -3 M coumarin and 10 -1 M CCC in the storage medium extended the longevity of the cultures for 67 days. Low levels of osmotica in the storage medium (100 mM sorbitol and 5% PEG) did not inhibit the germination of synthetic cocoa seeds whereas, higher levels (500 mM sorbitol and 15% PEG) had a negative influence on the cultures. Among the different osmotic treatments, 250 mM sorbitol fortified medium was found to be best as it could arrest radicle emergence in 42.97 % cultures. Longevity of more than 40 days were observed for synthetic seeds subjected to desiccation treatment: 85.3% RH (36 hours), 78.6% RH (24 hours and 36 hours) and 46.6% RH (18 hours and 24 hours). A longevity of only 15 days were obtained for synthetic seeds subjected to low temperature treatment in refrigerated conditions at 4ºC. The synthetic seeds stored in 10 M CCC and 10 -3 M coumarin added storage medium, when transferred to ½ MS basal medium after 60 days showed a maximum storage life of 98 days and 92 days respectively. The study was able to enhance the storage life of synthetic cocoa seeds by 9 days compared to a previous study by Shiran, (2012). Based on the results of the experiments conducted, a protocol for short and medium term storage of cocoa seed was developed.