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2001 - 200912010 - 20161
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Subject: Others × Author: KAU × End date: 2019 × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Genetic cataloguing of hot chilli (Capsicum chinese JacQ.)
    (Department of Olericulture, College of Agriculture,Vellayani, 2001) Manju, P R; KAU; Sreelatha Kumary, I
    The research project "Genetic cataloguing of hot chilli (Capsicum chinense Jacq.)" was carried out in the vegetable research plot of the Department of Olericulture, College of Agriculture, Vellayani, during September 2000 to May 2001. The objective of the study was to catalogue the accessions based on the IBPGR descriptor for Capsicum and to estimate the genetic parameters for different traits in the germplasm for identifying superior lines based on yield, quality and pest and disease resistance. Thirty two accessions of C. ch inense collected from various sources upon cataloguing pointed out wide variation for several morphological characters. Analysis of variance revealed significant difference among the accessrons for all the characters studied namely, plant height, primary branches per plant, plant spread, days to first flowering, pollen viability, days to maturity, fruits per plant, fruit length, pedicel length, fruit girth, fruit weight, seeds per fruit, 1000-seed weight, yield per plant, yield per harvest, number of harvests, capsaicin, oleoresin, ascorbic acid and mosaic incidence. Among the accessions, CC 23 recorded the maximum yield (1649.72 g) as well as fruits per plant (637.44). CC 13 was the earliest to flower (54.67 days) with the maximum number of harvests (6.94) and least vulnerability index for mosaic (40.63). Fruits per plant recorded the maximum phenotypic and genotypic coefficients of variation, followed by yield per plant and fruit weight. High heritability coupled with high genetic advance was observed for fruits per plant, yield per plant, fruit weight, fruit girth and fruit length. Correlation studies and path coefficient analysis revealed that fruits per plant is the primary yield component as evidenced from its high positive correlation as well as high direct and indirect effects on yield. In the discriminant function analysis, CC 23 (Nemom, Thiruvananthapuram) ranked first, followed by CC 13 (Vithura, Thiruvananthapuram) and CC 7 (Vithura, Thiruvananthapuram). Based on the analysis for genetic divergence, the 32 accessions were grouped into six clusters, with the maximum intercluster distance observed between clusters I and VI. On the basis of the present study, the accessions CC 23, CC 13 and CC 7 were found to be promising with regard to yield, quality and mosaic resistance and the same may be utilized for further improvement.
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    ThesisItemOpen Access
    Efficiency of vermiconversion and decomposition of farm residues on soil health, yield and quality of banana (Musa spp.)
    (Department of Science and Agricultural Chemistry, College of Horticulture,Vellanikkara, 2016) Mayadevi, M R; KAU; Sushama
    An investigation entitled “Efficiency of vermiconversion and decomposition of farm residues on soil health, yield and quality of banana (Musa spp.)” was undertaken at College of Horticulture and Banana Research Station, Kannara during 2013-2015. The objectives of the study were to compare the efficiency of native and exotic earthworms on vermiconversion of farm residues and the effects of different modes of vermicomposting on soil health, yield and quality of banana and to evaluate the in situ decomposition of banana crop residues An experiment with seven treatments and three replications was laid out in randomized block design to assess the composting efficiency of native and exotic earthworms. Seven treatments included absolute control as soil (S), ex-situ compost in silpaulin vermibed without earthworms (Ex-C), ex-situ vermicompost in silpaulin vermibed using Perionyx excavatus (Ex-P), ex-situ vermicompost in silpaulin vermibed using Eisenia foetida (Ex-E), in-situ vermicompost in banana planting pits using Perionyx excavatus (In-P), in-situ vermicompost in banana planting pits using Eisenia foetida (In-E), in-situ compost in banana planting pits without earthworms (In-C). In the next study, the prepared composts were tested along with recommended doses of fertilizers and FYM to assess their effects on growth, yield and crop quality of banana var. Nendran in RBD with seven treatments replicated thrice. The treatments were absolute control (S), 300:115:450g N:P2O5:K2O plant-1 + FYM at the rate of 20 kg plant-1 (POP) , exsitu vermicompost in silpaulin vermibeds with Perionyx excavatus at the rate of 20 kg plant -1 (Ex–P), ex-situ vermicompost in silpaulin vermibeds with Eisenia foetida at the rate of 20 kg plant -1 (Ex–E) , in-situ vermicompost in crop pits with Perionyx excavatus at the rate of 20 kg plant -1 (In-P), in-situ vermicompost in crop pits with Eisenia foetida at the rate of 20 kg plant -1 (In-E), in -situ compost at the rate of 20 kg plant -1 (In-C). After the harvest of the crop, the entire residues from each plant was incorporated in the respective crop pits and the insitu degradation of the banana residues was monitored. The salient findings are summarized as follows In the first trial, the composting efficiency of native and exotic earthworms under different modes of composting was compared. Chemical properties of compost like pH, electrical conductivity, and content of primary nutrients were significantly affected by modes of composting. Exotic earthworms like Eisenia foetida produced higher auxin content in the compost whereas Perionyx excavatus registered higher dehydrogenase activity under ex-situ mode of composting. The total microbial load was recorded in the compost prepared without earthworms under both modes of composting. Compost yield was more in ex-situ composting methods and Eisenia foetida was more efficient in composting as compared to Perionyx excavatus. Humic acid characterization by Fourier Transform Infra-Red spectroscopy revealed a similar spectra from different treatments and were found to be characterized by aromatic rings and triple bonded skeleton. Presence of relatively higher quantity of polysaccharide like substances was observed in insitu mode of composting. The spectra of humic acids for ex-situ composts prepared using Perionyx excavatus revealed a nitrate band of characteristic shape appearing prominently. Perionyx excavatus produced humic acids with high aromaticity both under ex-situ and in-situ mode of composting. Scanning electron microscopy revealed neo-formed CaCO3 nodules embedded in humic acids in the ex-situ vermicompost produced by Eisenia foetida. Transmission Electron Microscopy of humic acids indicated a globular structure for vermicompost prepared by Perionyx excavatus and a lamellar structure with voids for vermicompost prepared using Eisenia foetida. On field experimentation with different treatments using Nendran banana as the test crop, the highest yield was obtained for combined application of fertilizers and farm yard manure as per POP. Number of fingers per hand and number of functional leaves were found to influence the yield, irrespective of treatments. The number of days to bunching and harvest was significantly reduced for banana under in-situ composting. Higher content of total, reducing and non-reducing sugars were observed for in-situ composting treatments. On the contrary, higher titratable acidity was recorded for the control treatment. Both vitamin C content and sensory parameters were complimentary for POP treatment. Increased absorption and translocation of nutrients such as N, P, K and Mg in fruits were observed under organic nutrition using Perionyx excavatus. For the next study, the residues of banana were added to the respective pits for monitoring the carbon and nitrogen mineralization. The carbon mineralization with respect to time was fitted to single pool exponential model to derive the rate of mineralization and half-life. It revealed crop residues pre-treated with vermicompost using exotic earthworms had a higher rate of C cumulative mineralization. Nitrogen addition by both exotic and native species of earthworms were almost similar under in-situ conditions. The banana residue decomposition by Eisenia foetida was about 3.5 times higher than that of Perionyx excavatus. Calcium content of Perionyx excavatus pre-treated residues added the maximum calcium to the soil.