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2016 - 201891
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Author: KAU × End date: 2018 × Start date: 2016 × Type: Thesis × Thesis Type: Ph.D ×
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    ThesisItemOpen Access
    Characteization and evaluation of nutmeg (Myristica fragrans Houtt.) accessions
    (Department of Plantation Crops and Spices, College of Horticulture, Vellanikkara, 2016) Vikram, H C; KAU; Mini Raj, N
    Nutmeg (Myristica fragrans Houtt.) is an introduced crop to India. There exists tremendous variability in the nutmeg population in Kerala, which is the major nutmeg growing state in the country. Assessment of the existing variability is a prerequisite for taking up successful crop improvement programmes, which is very much limited in this tree spice. In this context, the present study entitled “Characterization and evaluation of nutmeg (Myristica fragrans Houtt.) accessions” was taken up exclusively with the specific objectives to characterize nutmeg accessions based on morphological, biochemical and molecular parameters so as to scale the variability in a multidimensional way. Select fifty nutmeg accessions from a core germplasm collected and maintained in a private plantation in the Chalakudy river basin, belonging to age of fifteen years, formed the material for the study. Among the select fifty accessions, forty two were females, four monoecious and four males. In the morphological characterization, 51 qualitative and 38 quantitative characters were recorded from two trees per accession. Biochemical characterization was done in the select seventeen distinct accessions. GC-MS profiling was done in kernel and mace oils. Biochemical constituents of fresh pericarp were estimated. Isozyme profiling was done for peroxidase and polyphenol oxidase enzymes. The molecular characterization was attempted with 21 RAPD and 12 ISSR primers after screening. A key for identification of an elite nutmeg tree was developed. A descriptor for nutmeg with a set of 51 qualitative and 38 quantitative parameters and descriptor states for each of these characters was developed as the first step. This is the first study of its kind to develop a minimal descriptor for nutmeg. The descriptor developed from the present study was simultaneously utilised for morphological characterization and evaluation of the accessions. Wide variability was noticed among the accessions for 47 out of 51 qualitative characters. Four characters viz., leaf margin, fruit pubescence, grooves on nut and nature of fruit dehiscence were noted as non variable characters and hence, these were not included for further analysis. Based on the qualitative characters, accessions were classified into 11 clusters at 66 per cent similarity level. Accessions differed significantly for all the quantitative characters except shelling percentage. Performance evaluation of the accessions brought out the superiority of accession 8, 9 and 22 for yield. The accessions showed high GCV, PCV, h2 and genetic gain for most of the characters. Number of fruits per tree, fruit set percentage, number of fruits per m2, fresh and dry weight of mace, mace volume as well ratio of nut to mace exhibited high genetic gain. Hence, selection programme based on these characters will be very effective in improving the base populations. Based on Mahalanobis D2 analysis, accessions were grouped into 10 clusters. Wide range of variation was observed in contents of volatile oil, oleoresin and fixed oil of kernel and mace. Based on these constituents accessions were grouped into 26 clusters, which indicated their distinct quality. Based on the results of the morphological characterization, seventeen distinct accessions were selected for further biochemical and molecular analysis. GC-MS analysis of kernel and mace oils exhibited 20 and 24 constituents respectively. Volatile oil composition exhibited wide variability for the major constituents viz., myristicin, elemicin, safrole and sabinene apart from the presence of some unique compounds. Grouping of the accessions was done based on the per cent content of these important compounds. Two accessions recorded high contents of both myristicin and elemicin whereas another two accessions were in the complimentary; belonging to low myristicin group. High sabinene combined with low myristicin was the intrinsic quality attribute of one of the accessions. Change, as well as addition/deletion of specific constituents was also noticed in the volatile oils after storage for one year. Accessions exhibited wide range of variation in the biochemical constituents of pericarp, a valuable information for the value addition of pericarp. Total phenol and tannins exhibited high variation. The accessions were ranked based on the content of biochemical constituents. Isozyme profiling using peroxidase enzyme produced four bands and that based on polyphenol oxidase exhibited three bands. Molecular markers could assess the variability among the accessions. The selected 21 RAPD primers produced a total of 164 amplicons of which 63.21 per cent were polymorphic. The 12 ISSR primers selected produced a total of 87 amplicons of which 69.44 per cent were polymorphic. Few unique bands were detected for specific characters. Inter cluster association of each of the qualitative clusters with other clustering patterns was worked out. The results indicated the differences as well as similarities of the qualitative clusters with other clustering patterns. Finally, key quantitative characters were identified based on their direct and indirect effect on yield as also economic importance. The statistical key thus developed using 13 key quantitative characters will serve as a preliminary tool for identification of an elite nutmeg tree.
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    ThesisItemOpen Access
    Groundwater irrigation: management, adaptation and economic costs under declining resource conditions
    (Department of Agricultural Economics, College of Horticulture, Vellanikkara, 2017) Seenath Peedikakandi; KAU; Indira Devi, P
    Groundwater is the major source of domestic use and irrigation in Kerala, accounting for 39 per cent of net irrigated area. Irrigated agriculture in the state shows continuous increase over years. At the same time Kerala is reported as third among the states with highest depletion of groundwater. This situation poses challenges in agricultural production. The study ‘Groundwater irrigation: Management, adaptation and economic costs under declining resource conditions’ was undertaken, in this background. The objectives of the study were to analyse the extent of decline in groundwater resources and farmers’ understanding of the same, to analyse the extraction practices, management and economic efficiency of groundwater irrigation and coping (short term) and adaptation (long term) strategies towards management of groundwater decline and the economic cost of adaptation strategies. The study was conducted in Palakkad district of Kerala. Based on the stage of ground water development, three Block Panchayats viz., Chittur (over exploited), Malampuzha (critical) and Pattambi (semi-critical) were selected for the study. 50 Open Well (OW) irrigated and 50 Bore Well (BW) irrigated farms from each BP were randomly selected from the Grama Panchayats (GPs) where observational wells of the GWD (Ground Water Department- Kerala) are situated. Primary data was collected from the sample farms through field visits using pre-tested structured interview schedule and through direct observation. PRA (Participatory Rural Appraisal) was also conducted in each BP to draw the time line of changes in ground water status and social perceptions. Secondary data on monthly water levels of Groundwater Monitoring Wells (GMWs) maintained by GWD (Palakkad),rainfall data and published reports were used for the study. Statistical tools like descriptive analysis, regression and Stochastic Frontier Function were employed for analysis of the data. In most of the GMWs in the study area, the Water Level from Ground (WLG) has been declining over the years. The trend was more predominant during early summer (Dec.–Jan.) in Chittur and Malampuzha and in late summer in Pattambi BP. Regression analysis showed that WLG was significantly influenced by one year lagged rainfall in Chittur and current year rainfall in Malampuzha and Pattambi. The average well density was 205/km2 with highest in Pattambi. Density of defunct wells was highest (45/km2) and the average functional age of bore wells was lowest (7 years) in Chittur. The depth of well was highest in Chittur where bore well depth (136 mbgl- meters below ground level) was double than that of Pattambi. Coconut based cropping system was prevalent in most of the farms except in Malampuzha where paddy was the major crop. Flood, basin and sprinkler irrigations were found to be more common in Malampuzha and Pattambi BPs, while drip irrigation was prevalent in Chittur. Cost of irrigation in Chittur was about Rs. 29,000/ha/year which accounted for 37 per cent of cost of cultivation. Annual net return per ha. of farm was lowest (Rs. 17,640/-) in Chittur due to low cropping intensity. Stochastic Frontier Analysis indicated that mean economic efficiency was high (99.9%) in Chittur as most of the farms were functioning along the cost frontier. The variability among the farms in Chittur was low. Respondents opined that groundwater is declining over the years irrespective of the region. It has been so, for more than a decade in Chittur affecting socio-economic well-being of farmers. They attributed intensive extraction through bore wells and low rainfall as the major reasons for the decline. Farm level adaptations to water scarcity are classified under ‘supply management’ (methods that facilitated increase in quantity of water available for irrigation) and ‘demand management’ (methods that tried to use the water effectively through minimizing the use) strategies. The supply management strategies were mainly exploitative in nature which included digging new bore well (52-58%), improved draft technology with compressor pumps (58%), taking pits for water conservation (7%), coconut husk burial (12%), coconut leaf mulching (18%) and dependence on water markets (8%). Digging new bore well was the most common supply management strategy in Chittur which is highly capital intensive. The average cost amounted to Rs. 8,520/ha/year. Intensive extraction was done by excessive use of subsidized electricity. Adoption of drip irrigation (60%) was the most widely practiced demand management strategy which cost about Rs. 22,000/ha/year. Cropping pattern change from paddy and sugarcane to coconut was also observed. About 18 per cent of the land area in Chittur was kept fallow due to water scarcity. The study brings out results that suggest policy interventions in regulating bore well digging and revisiting the power subsidy system. In Chittur area, where the rainfall is scanty, extension of the Right Bank Canal of the Chittur River irrigation project is the most feasible solution. Taking up on-farm research trials in the area to suggest efficient farming systems and practices may also be done. Simultaneously water resource conservation strategies are to be popularized through awareness creation, capacity building programmes and subsidy support.
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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.
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    ThesisItemOpen Access
    Silicon availability of tropical soils with respect to rice nutrition
    (Department of Soil Science and Agricultrural Chemistry, College of Horticulture,Vellanikkara, 2016) Arya Lekshmi, v; KAU; Jayasree Sankar, s
    Silicon (Si) is the second most abundant element in soil. The amount of silicon in soil depends on parent material, soil type, pedogenic process and landscape. In soil solution, Si is present as monosilicic acid which is the only form that the plant can absorb from soil. The productivity of rice is comparatively low in soils of Kerala. As a ̳Si – accumulator‘, rice can benefit from Si nutrition. The application of Si can enhance growth and yield of rice. With this background, studies were conducted to categorize major rice growing soils of Kerala according to plant available silicon and to evaluate the efficacy of different sources of silicon including rice straw in wetland rice. The release of silicon from different soils added with various silicon sources under different water regimes was also monitored. Soil samples were collected from five different locations representing major rice growing regions of Kerala viz., Kuttanad, Kole land, Pokkali, sandy and lateritic to categorize them according to plant available silicon. The available Si ranged from 7.70 mg kg -1 (sandy soil) to 34.91 mg kg -1 (Kole land soil) in the order Kole land > Pokkali > lateritic > Kuttanad > sandy soil. All the soils under study were categorized as low in available Si. The available Si had positive correlation with organic carbon, available N, Ca, Mg, Fe, Mn, Zn, exchangeable K, Ca, Mg and CEC and negative correlation with available boron, AEC and silica-sesquioxide ratio. These soils were subjected to fractionation of silicon. The major fractions of Si were mobile, adsorbed, organic, occluded, amorphous and residual Si. The percentage distribution of fractions of Si in these soils were in the order; residual Si > amorphous Si > occluded Si > organic Si > mobile Si > adsorbed Si. Quantity – intensity relationship of five major rice growing soils at two temperatures viz. 25 0 C and 40 0 C were studied. The highest buffer power was indicated by Kuttanad soil followed by Pokkali and sandy soils at 25 0 C. It clearly indicated that these soils have a higher power to retain Si on solid phase and replenish its concentration in soil solution as and when it is depleted through plant uptake or leaching. The equilibrium Si concentration and the amount of Si adsorbed by each soil were used to test the fitness of data to the adsorption isotherms viz., Langmuir, Freundlich and Temkin. The data obtained from the adsorption experiments fitted into Freundlich and Temkin equations, but not to Langmuir equation at 25 0 C. At 40 0 C no adsorption equations were obtained for any soil.An incubation study was conducted to know the extent of release of Si on addition of different sources of silicon such as rice husk ash, biodecomposed rice husk, calcium silicate and sodium silicate in five rice growing soils under submerged water regime (SWR) and field capacity water regime (FCWR). Addition of Si significantly increased the release of available Si in all soils except Kole land soil after a month. Kole land soil showed higher release of available Si after two months. The highest release of available Si was at SWR in case of Kole land and Kuttanad soil, where as Pokkali, sandy and lateritic soils showed more release of available Si at FCWR. Irrespective of soils, treatment with sodium silicate showed higher release of available Si. Total Si showed a decreasing trend over the period of incubation for three months in all the soils. A field experiment was conducted at Agronomic Research Station, Chalakudy to evaluate the efficacy of different sources of silicon including rice straw in wetland rice. Rice husk ash, biodecomposed rice husk, calcium silicate and sodium silicate were used as source of Si along with fertilizers as per package of practice recommendation (NPK alone). The maximum number of panicles per hill, number of spikelets per panicle, thousand grain weights and minimum number of unfilled grains per panicle were recorded in treatment with calcium silicate application. The maximum grain yield of 6.90 t ha -1 was recorded in treatment T 5 (T 2 + Calcium silicate) and significantly superior (fig.54) over all other treatments. This increase in yield may be due to the effect of application of Si on soil fertility, nutrient uptake, and plant growth. The direct effect of Si fertilization on increased number panicle per hill, number of spikelets per panicle, and thousand grain weight and decreased number of unfilled grains per panicle might be the reason for increased grain and straw yield in treatment with calcium silicate. The treatment with POP + sodium silicate showed the highest uptake of Si by grain and straw of rice. The sources of Si had no residual effect on grain and straw yield of succeeding rice crop. In general, sandy soil low in available Si had a high response to applied Si in achieving higher grain yield.
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    ThesisItemOpen Access
    Integrated management of foliar fungal disease of culinary melon (Cucumis meloL. var. acidulus Naudin)
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2016) Narmadhavathy, S; KAU; Kamala Nayar
    The project entitled “Integrated management of foliar fungal disease of culinary melon (Cucumis melo L. var. acidulus Naudin)” was undertaken with the objective of making a comparative evaluation of the efficacy of foliar application of fertilizers, micronutrients, bio-control agents and newer fungicide for the management of Colletotrichum leaf spot (Colletotrichum sp.) disease of culinary melon. Surveys conducted during September 2013 to December 2013, in ten culinary melon fields located at Instructional Farm (IF), College of Agriculture (CoA), Vellayani as well as in farmers’ fields near, CoA, Vellayani, in order to assess the prevalence of major diseases such as Colletotrichum leaf spot and downy mildew disease affecting the crop. Highest disease incidence (DI) and percentage disease index (PDI) of Colletotrichum leaf spot were observed, 75 days after sowing, at Chavadinada (70.00 per cent and 64.44 per cent respectively). Incidence and index of downy mildew disease were recorded in four out of the ten locations surveyed (Palapoor, Papanchani, Kalliyoor and Punjakari). Maximum disease incidence and percentage disease index of downy mildew disease (36 per cent and 33.33 per cent respectively) were observed at Papanchani. The most virulent isolate of anthracnose leaf spot pathogen (IF, Vellayani isolate), obtained during the survey was identified as Colletotrichum fructicola by molecular characterization. The treatment NPK 19:19:19 (0.5 per cent) combined with the fungicide mancozeb (0.4 per cent) and adjuvant was most effective in inhibiting the mycelia growth of the pathogen C. fructicola, in vitro, (100 per cent) over control as well as in suppressing artificially induced anthracnose disease and improving the growth parameters of the plants, in the two greenhouse experiments conducted at the CoA, Vellayani during March to June 2014 and August to October, 2014. Results of two field trials conducted at CoA, Vellayani, during January to March, 2015 and April to June, 2015 for testing four most effective treatments screened from the greenhouse experiments, indicated that NPK 19:19:19 (0.5 per cent) + azoxystrobin (0.15 ml/l) + adjuvant (DI 40.00 and PDI 13.05 respectively) and NPK 19:19:19 (0.5 per cent) + mancozeb (0.4 per cent) + adjuvant (DI 40.00 and PDI 13.47 respectively) were most effective in managing the disease and also increasing total yield of plants, when compared to the remaining treatments. Trials were conducted in farmers’ fields at three locations (Venganoor, Vavamoola and Venjaramoodu) for confirming the efficacy of the two most effective treatments screened from the field trials conducted at CoA, Vellayani and pooled analysis of the results indicated that the lowest PDI (12.22) and DI (28.50) were obtained in plants treated with NPK 19:19:19 (0.5 per cent) + azoxystrobin (0.15ml/l) + adjuvant, which was significantly superior to the other treatments. Results of the microbial studies indicated that there was decline in fungal flora of the plants treated with foliar fertilizer NPK 19:19:19 (0.5 per cent) + azoxystrobin (0.15 ml/l) + adjuvant, days after application of treatments whereas bacterial population was higher in plants applied with the same treatment when compared to the application of combination of foliar fertilizer NPK 19:19:19 (0.5 per cent) + mancozeb (0.4 per cent) + adjuvant. There was indication of higher induction of systemic resistance in plants treated with NPK 19:19:19 (0.5 per cent) + azoxystrobin (0.15 ml/l) + adjuvant due to the higher activity of defense related enzymes, such as phenylalanine ammonia lyase (PAL), peroxidase (PO), polyphenol oxidase (PPO), β-1,3glucanase, super oxide dismutase (SOD) and the compound phenol, all of which, reached maximum level on the 15th day after treatment. Leaf samples obtained from plants treated with foliar fertilizer NPK 19:19:19 (0.5 per cent) + azoxystrobin (0.15 ml/l) + adjuvant indicated highest nutrient use efficiency in all three locations of the confirmation trials while highest pigment status due to this treatment was observed in the trial conducted at Venganoor. Relative water content was generally high in leaf samples collected from all plants irrespective of the treatments, although it was comparatively low, in leaf samples obtained from plants of absolute control plot. Epicuticular wax content was slightly lower in the plants treated with combination of the foliar fertilizer NPK 19:19:19 (0.5 per cent) and fungicides, either azoxystrobin (0.15 ml/l) or mancozeb (0.4 per cent) + adjuvant. Stomatal frequency on the upper and lower surfaces of leaves was not much affected by application of foliar fertilizer NPK 19:19:19 (0.5 per cent) combined with the fungicides. B:C estimated ratio revealed that the highest returns were obtained from the plants treated with foliar spray of NPK 19:19:19 (0.5 per cent) + azoxystrobin (0.15 ml/l) + adjuvant, in all three locations of the farmers’ field trials. This study presents the first report of the pathogen Colletotrichum fructicola causing anthracnose leaf spot disease of culinary melon in India. In field conditions, combination of the foliar fertilizer NPK 19:19:19 (0.5%) and azoxystrobin (0.15 ml/l) along with adjuvant applied twice at 15 days’ interval was most effective in controlling anthracnose leaf spot disease of culinary melon and also increasing the yield of the crop.
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    ThesisItemOpen Access
    Supply chain analysis of marine fish marketing system in Kerala
    (Department of Agricultural Economics, College of Horticulture, Vellanikkara, 2017) Jeyanthi, P; KAU; Jesy Thomas, K
    Fisheries is a major allied sector of agriculture contributing about 0.8 per cent to the Gross Domestic Product (GDP) and 5.15 per cent to agricultural GDP in India. Marine fisheries supports around 10 million people providing livelihood and employment directly or indirectly. Fish also provides more than one billion people living below the poverty line with most of their daily animal protein requirement globally. Kerala is a state known for its fish consumption which is more than four times the national average. However, the marine domestic fish marketing system faces several challenges in the process of distributing fish from the producer to the consumer. The study was conducted in Kerala state, which is the fourth largest fish producer in the country, and covered coastal and land locked (non-coastal) regions. The objectives of the study were to identify the supply chain of selected fish species, to assess the structure and performance of domestic fish markets, to examine the market integration and price transmission among the markets and to assess the consumer perception and suggest policy guidelines for improved fish marketing in Kerala. Two coastal districts viz., Ernakulam (E) and Kollam (K) and two land locked districts, Idukki (I) and Pathanamthitta (P) were selected and data was collected using simple random sampling from various marketing functionaries (producers, wholesalers, retailers and consumers). Since the species composition of marine fish landings is varied, the study focused on four high value (seer fish, shrimp, pomfret and tuna) and four low value but commonly consumed fish species (sardine, mackerel, anchovies, threadfin bream). Supply chain of the selected fish species was identified using the framework of Feller et al, 2006. Market performance of producers, wholesalers and retailers were assessed using Data Envelopment Analysis. The co-integration test was used to analyses the market integration of selected market pairs. Conjoint analysis was used to determine the attributes responsible for their fish purchasing behaviour. The constraints faced by the market functionaries were ranked using Rank Based Quotient. The generic supply chain of fish identified involved the auctioneer, wholesaler, retailers, secondary retailers, between the producer and the consumer. This is almost similar to the supply chain of other perishable like fruits, vegetables and flowers. The supply chain for sardine, tuna and thread fin bream also involved extra nodes in their supply chain due to industry specific demands like feed and other specialized products. The market structure of domestic fish markets was not efficient. The main reason being lack of infrastructure such as cold storage, well planned display and assemblage platforms, potable water and weighing balance. Market performance of producers was measured at the five landing centres in Ernakulam and Kollam and it was observed that only one market was efficient in each of the districts. It was revealed that the nature of inefficiency was due to scale rather than technology. In both Ernakulam and Kollam, only one wholesale market each was efficient and all other markets showed high technical efficiency i.e., above 0.80. In both wholesale and retail markets, the technical efficiency was relatively low in Idukki and Pathanamthitta with it being least in Idukki. It was revealed that the markets in the coastal regions showed relatively high technical efficiency than the land locked regions because of the higher volumes handled in the markets due to proximity with the landing centres, viz, the primary production centres, which is not so easily accessible to the land locked districts. Among wholesale markets, one market pair in Ernakulam, one in Idukki and one in Pathanamthitta showed co-integration and among retail one each in Ernkulam and Pathanamthitta showed co-integration. This indicates that in these markets there is a possibility of long run equilibrium in prices. The existence of low short run market integration (SRMI) at both wholesale as well as retail market levels was observed among the co-integrated market pairs. Consumer preference was for fresh fish in all the four districts studied in cleaned and cut form from retailers, wholesalers or wholesaler-cum-retailer. Sardine was the most preferred species in both coastal and landlocked regions of Kerala with more than 75 and 72 per cent of respondents, respectively, consuming it daily. The relative importance of attributes that consumer in Ernakulam and Kollam looked at while purchasing fish was fish species in fresh form and income. In Idukki and Pathanamthitta, availability and income were the relatively important attributes. Based on the pooled response of market functionaries in the selected districts the domination of middlemen was the major constraint for producers, wholesalers and retailers. Safety and quality of fish was the major constraint of consumers. The studies on efficiency of fish supply chain in line with the changing consumer preference are the future line of work towards sustainable fisheries development.
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    ThesisItemOpen Access
    Strain improvement of oyster mushrooms- pleurotus cystidiosus O.K. Mill and pleurotus opuntiae (Durieu and LEV.) SACC.
    (Department of Plant Pathology, College of Agriculture, Vellayani, 2018) Krishnapriya, P J; KAU; Geetha, D
    The present study entitled “Strain improvement of oyster mushrooms: Pleurotus cystidiosus O.K.Mill and Pleurotus opuntiae (Durieu and Lev.) Sacc.” was carried out in College of Agriculture, Vellayani during 2015-2018, with the objective to standardize the techniques for production of oyster mushrooms: P. cystidiosus and P. opuntiae; and to study their morphological, physiological and cultural characteristics as well as nutritional and organoleptic qualities; and to undertake genetic improvement by protoplast fusion. The mushrooms were collected from two locations of Thiruvananthapuram and three fast growing isolates of Pleurotus spp. viz., PC2 (Vellayani), PNC1 (Chirayinkeezhu) and PO1 (Vellayani) were selected for the study. These isolates were identified as P. cystidiosus subsp. abalonus, P. cystidiosus and P. opuntiae using internal transcribed spacer (ITS) primers and subsequent sequencing; and registered at Genbank database with accession numbers KY214254, KY887023 and KY214255 respectively. The fast growing isolates of P. cystidiosus (coremial), P. cystidiosus (non-coremial) and P. opuntiae recorded maximum growth on PDPA amended with one per cent yeast under dark condition. The optimum temperatures for the growth were 30 0C, 25 to 30 0C and 25 0C respectively whereas, the optimum pH were 8, 8 and 7 to 8 respectively. Studies with different substrates and amendments for spawn production revealed that sorghum with one per cent yeast was the best for P. cystidiosus (coremial) and P. opuntiae whereas, paddy grains with one per cent yeast for P. cystidiosus (non-coremial). Experiments with different substrates and amendments for mushroom production revealed that rubber wood sawdust sprayed with 2.5 per cent of 1 M potassium dihydrogen phosphate recorded the maximum BE for P. cystidiosus (non-coremial) (192.76 per cent). P. opuntiae recorded the maximum BE in rubber wood sawdust amended either with 4 per cent neem cake (91.38 per cent) or wheat bran (91.37 per cent). Major insect pests observed in the beds of Pleurotus spp. were phorid flies, spring tails, black ants and staphylinid beetles. The competitor moulds observed were different species of Coprinus, Aspergillus, Penicillium and Trichoderma. Sporocarps soaked in one per cent CA for 15 minutes followed by mechanical drying and powdering was the best post harvest treatment for both P. cystidiosus (non-coremial) and P. opuntiae. Mycelium of P. cystidiosus (coremial) showed black coremial structures, representing its asexual stage (Antromycopsis broussonetiae Pat. & Trab.). The coremia comprised of elliptical (16.31 µm x 7.48 µm) and round conidia (8.06 to 8.49 µm). The black colour of coremia was due to melanin which was extracted (255.56 mg l-1) and characterized. The performance of long duration P. cystidiosus (non-coremial) and short duration P. opuntiae was compared with two ruling mushrooms of Kerala viz., long duration P. florida (Mont.) Singer and short duration P. eous (Berk.) Sacc. The study revealed that P. cystidiosus (non-coremial) and P. opuntiae showed higher BE compared to P. florida and P. eous, respectively. P. cystidiosus (non-coremial) recorded maximum moisture (94.05 per cent), starch (200.55 mg g-1), protein (30.2 mg g-1), fat (4.25 per cent), antioxidants (485.45 μg equivalent gram of ascorbic acid-1), beta-carotene (25.69 µg 100 mg-1), polyphenols (7.55 mg g-1) and energy (359.45 Kcal) compared to other Pleurotus spp. Sensory evaluation of mushroom products made from the species of Pleurotus was done and masala curry prepared from P. cystidiosus (non-coremial) scored the maximum value for overall acceptability. Shelf life of P. cystidiosus (non-coremial) was higher (5 days) compared to P. opuntiae, P. florida and P. eous (3 days each) in perforated poly propylene covers stored under refrigeration. Vanillin (0.05 per cent) and carbendazim (1 mM) were selected as dual biochemical markers for the PEG mediated protoplast fusion. Three days old P. cystidiosus (non-coremial) and four days old P. opuntiae recorded the maximum protoplast yield at five and four hours after incubation respectively with 0.6 M KCl and 30 mg ml-1 of enzyme consortium. Eight fusant lines with varied mycelial characters were obtained. Among fusants, F6 and F8 did not segregate in the second generation whereas, F4 segregated. F6 and F8 recorded higher BE of 168.05 and 99.95 per cent respectively compared to the parental lines and other fusants. Sporocarp of F6 and F8 was morphologically similar to P. cystidiosus (non-coremial) and P. opuntiae respectively; and F8 also exhibited low temperature adaptability. The present investigation indicated the exploitability of two promising isolates viz. P. opuntiae for tropical areas and P. cystidiosus (non-coremial) for cooler regions of Kerala using locally available materials and the standardized cultivation practices. The present study also standardized the protoplast fusion technique between P. cystidiosus (non-coremial) and P. opuntiae; and two fusant lines (F6 and F8) recorded higher BE which can be used for future breeding programmes.
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    ThesisItemOpen Access
    Bioefficacy and soil health impact of flucetosulfuron in wet seeded rice (Oryza sativa L.)
    (Department of Agronomy, College of Agriculture, Vellayani, 2018) Arya, S R; KAU; Elizabeth, K Syriac
    The investigation entitled "Bioefficacy and soil health impact of flucetosulfuron in wet seeded rice (Oryza sativa L.) was carried out at College of Agriculture, Vellayani, Thiruvananthapuram during the period of 2015-2018. The objectives were to evaluate the bioefficacy of flucetosulfuron in wet seeded rice; to assess its impact on soil health by determining the microbial count, earthworm population, enzyme status and herbicide residue in soil through bioassay using indicator plant as well as to assess the weed seed bank. It was also envisaged to study the in vitro sensitivity of biofertilizer organisms and biocontrol agents to flucetosulfuron. Field experiment was conducted during the I and II crop seasons of 2016- ’17, in a farmer’s field in Kalliyoor Panchayat, Nemom block, Thiruvananthapuram district, Kerala, with 12 treatments replicated thrice in Randomized Block Design. The treatments were: T1 : Flucetosulfuron @ 20 g ha-1 at 2-3 DAS, T2 : Flucetosulfuron @ 25 g ha-1 at 2-3 DAS, T3 : Flucetosulfuron @ 30 g ha-1 at 2-3 DAS, T4 : Flucetosulfuron @ 20 g ha-1 at 10-12 DAS, T5 : Flucetosulfuron @ 25 g ha-1 at 10-12 DAS, T6 : Flucetosulfuron @ 30 g ha-1 at 10-12 DAS, T7 : Flucetosulfuron @ 20 g ha-1 at 18-20 DAS , T8 : Flucetosulfuron @ 25 g ha-1 at 18- 20 DAS , T9 : Flucetosulfuron @ 30 g ha-1 at18-20 DAS, T10: Bispyribac sodium @ 25 g ha-1 at 15 DAS, T11: Hand weeding at 20 and 40 DAS and T12 : Weedy check. The short duration variety Kanchana was used for the trial. The weed flora in the experimental field comprised of four species of grasses, six species of broad leaved weeds and three species of sedges. Based on density and dry weight, sedges were the predominant group in the experimental field followed by broad leaved weeds and grasses. Application of flucetosulfuron @ 20, 25 and 30g ha-1 at 10-12 and 18-20 DAS (T4, T5, T6, T7, T8 and T9) recorded lower total weed density, total weed dry weight and nutrient removal by weeds and higher total weed control efficiency and were on par with the hand weeding treatment (T11). Yield reduction due to weeds was found to be 52.33 and 55.61 per cent during the I and II crop seasons respectively. The highest grain yield was recorded by the application of flucetosulfuron @ 25 g ha-1 at 10-12 DAS (T5) and flucetosulfuron @ 20 g ha-1 at 10-12 DAS (T4) during the first and second crop seasons respectively. The same trend was observed in the case of dry matter production also. Pooled analysis of the grain yield for the two seasons indicated the superiority of T5 which recorded the highest grain yield of 8.33 t ha-1. This treatment was on par with the other levels of flucetosulfuron viz., 20 and 30 g ha-1 at 10-12 DAS (T4 and T6) and hand weeding treatment (T11). Higher yield attributes, harvest index and nutrient uptake were also recorded for these treatments. However, net income and B:C ratio were significantly lower for hand weeding treatment. Herbicide application did not cause any significant inhibitory effect on the earthworm population and spider count. Application of herbicides increased the microbial population in herbicide treated plots. Flucetosulfuron, at the tested doses (20, 25 and 30 g ha-1) and time of application (2-3, 10-12 and 18-20 DAS), did not show any adverse impact on the activity of soil enzymes (dehydrogenase, acid phosphatase and urease) and soil organic carbon status. To identify the most suitable indicator plant for assessing flucetosulfuron residue in soil, four separate pot culture experiments were conducted using barnyard millet, cucumber, sunflower and maize. Sunflower was identified as the most sensitive indicator plant and shoot length of sunflower was adjudged as the best parameter to assess the flucetosulfuron residue in soil. Bioassay after each field experiment using sunflower revealed that there was no residual toxicity of flucetosulfuron in the post experiment soil. Pot culture experiments were carried out before and after each field experiment, to study the weed seed bank dynamics. Results revealed that non- herbicidal plots recorded higher weed count compared to herbicide applied plots. In all the herbicide treated plots, effective reduction in weed seed bank could be obtained irrespective of the dose of the herbicide. Regarding the time of application, application of flucetosulfuron at 10-12 and 18-20 DAS caused significant depletion of weed seed bank during both the seasons compared to its application at 2-3 DAS. In vitro sensitivity of biofertilizer organisms viz., Azospirillum lipoferum, Azotobacter chroococcum, Bacillus megaterium and Frateuria aurantia to flucetosulfuron indicated that growth of none of the organisms were significantly inhibited by the tested doses of flucetosulfuron. Similarly, in vitro sensitivity to biocontrol agent Trichoderma viride revealed that, at all the tested concentrations of flucetosulfuron, it showed a colony diameter of 9 mm uniformly with zero per cent inhibition indicating the compatibility of the herbicide. The compatibility studies with Pseudomonas fluorescens also revealed the safety of the herbicide. The present study revealed that application of flucetosulfuron @ 20, 25 and 30 g ha-1 at 10-12 DAS was very effective in controlling the weeds and recorded significantly higher grain yield and monetary benefits in wet seeded rice. Application of flucetosulfuron @ 20, 25 and 30 g ha-1 at 2-3/10-12/18-20 DAS had no adverse impact on soil health and was found compatible with the tested biofertilizer organisms (Azospirillum lipoferum, Azotobacter chroococcum, Bacillus megaterium and Frateuria aurantia) and biocontrol agents (Trichoderma viride and Pseudomonas fluorescens).
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    ThesisItemOpen Access
    Breeding cowpea (Vigna unguiculata (L.) Walp.) for resistance to spotted pod borer (Maruca vitrata Fab.)
    (Department of Plant Breeding and Genetics, Vellanikkara, 2018) Ambavane Ajinkya Rajendra; KAU; Jiji Joseph
    Cowpea [Vigna unguiculata (L.) Walp.] is important pulse crop rich in nutrients, especially proteins. This crop is cultivated in the tropics of Asia, Africa and other parts of the world. Nevertheless, the production of cowpea is unable to achieve its summit. One of the prime reasons for this is the infestation of a notorious pest, the spotted pod borer, (Maruca vitrata Fab.; Lepidoptera: Crambidae). Spotted pod borer is one of the most important post-flowering pests of cowpea in the tropics. It is a major lepidopteran pest and damage cause to cowpea by the pest almost always crosses economic threshold level. Hence, the present investigation was conducted in the Department of Plant Breeding and Genetics, College of Horticulture, Vellanikkara, Kerala Agricultural University, Thrissur during 2015 to 2018 with the objective of identification and incorporation of resistance against spotted pod borer in high yielding varieties of cowpea and assessment of parental polymorphism at the molecular level Thirty genotypes of cowpea formed the material for the study. These genotypes were subjected to field screening against spotted pod borer. These genotypes were also evaluated for morphological and biochemical basis of resistance. Five selected genotypes from experiment 1 then hybridised with four high yielding genotypes viz., Geethika, Vellayani Jyothika, Lola and Kashi Kanchan following Line × Tester mating design. Twenty F 1 hybrids evaluated for field resistance and the morphological basis of resistance. Progenies of selected F 1 hybrids grown as F 2 populations and evaluated for same parameters as like F 1 s. Thirty genotypes were also subjected to molecular screening by 40 SSR primers. Wide variation was observed in terms of different damage parameters. Ten genotypes viz., Hridya, Palakkadan thandan payar, EC 300039, EC 98668, EC 101216, IC 52110, IC 39945, IC 2918, IC 39922 and IC 39916 recorded total damage below five per cent. Among them, IC 39922 observed to have no flower bud and flower damage, EC 300039, EC 98668, IC 52110, IC 39945, IC 2918 and IC 39916 recorded no flower damage, whereas, Palakkadan thandan payar, IC 39945, IC 2918 and IC 39947 were free from pod damage. The highest damage was recorded in the variety Bhagyalakshmy (48.46 %) followed by variety Lola (30.04 %). Analysis of the morphological basis of resistance to spotted pod borer revealed the negative correlation of trichome density and length on flower bud, trichome density on the pod and pod wall thickness with respective damage parameters. With respect to the biochemical basis of resistance to spotted pod borer, total sugar content, reducing sugar content and non-reducing sugar content of flower bud and pod showed a positive correlation with damage parameters, but the correlation was not significant. However, the total protein content of pod showed a strong and positive correlation with pod damage. Total phenol content of flower bud showed strong negative correlation with damage parameters. Polyphenol oxidase activity in flower bud and pod exhibited a strong negative correlation with damage parameters. The crude fibre content of pod also showed a strong negative correlation with pod damage. In experiment 3, three SSR primers viz., CLM0061, CLM0295 and CLM0300 recorded high polymorphic information content (0.70, 0.71 and 0.76, respectively). Primer CLM0190 observed to have high amplicon size (307.03-415.73 bp). Jaccard’s similarity coefficient was highest between IC 52118 and IC 39916 (0.643) and was lowest between Kashi Kanchan and TVX-944 (0.022). Cluster analysis of SSR data grouped 30 genotypes in 22 clusters, and the 21 st cluster was observed to have more members (3 genotypes). Most resistant genotype, IC 2918, grouped in a separate cluster which proved its diverse nature from other genotypes. Principal component analysis of SSR data placed three yard-long bean genotypes viz., Geethika, Vellayani Jyothika and Lola near to each other in a two-dimensional score plot. The same analysis also formed two clusters with more number of genotypes which placed resistant and susceptible genotypes separately. In field screening of F 1 hybrids, Hybrid 20 observed to have total damage below 5 per cent. Eight hybrids recorded total damage in the range of 5 to 10 per cent. These hybrids were selected for next experiment. Line × Tester analysis of F 1 s revealed Kashi Kanchan, EC 98668 and IC 2918 as a good combiner for resistance against spotted pod borer. Hybrid 5, Hybrid 6, Hybrid 10, Hybrid 11, Hybrid 13, Hybrid 15, Hybrid 16, Hybrid 17, Hybrid 18, Hybrid 19 and Hybrid 20 observed to have desired negative heterosis (mid-parent) for total damage. In F 2 plant screening, Hybrid 1 population recorded low mean for total damage (6.76 %), whereas, the population of Hybrid 3 recorded high mean (12.17 %). Around 100 plants of F 2 generation recorded total damage below ten per cent. Out of them, around 38 plants also registered good yield. These plants should be further evaluated to isolate high yielding resistant segregants.