Research Symposium-2011

Permanent URI for this collection

https://erepo.lib.uwu.ac.lk/handle/123456789/6574

Browse

Browsing Research Symposium-2011 by Subject "Biology"

Now showing 1 - 9 of 9
  • No Thumbnail Available
    Item
    Comparative Efficacy of Selected Insecticides in Comparison with Chlorpyrifos to Control Tobacco Cutworm (Spodoptera litura)
    (Uva Wellassa University of Srilanka, 2011) Weerawansha, A.N.R.; Abeysekara, N.N.R.; Ranawana, S.R.W.M.C.J.K.
    Cigarette tobacco production is done by the registered farmers of Ceylon Tobacco Company for a pre-trade agreement while other types are grown purely on freelance basis and hence cigarette tobacco production has a better accountability. It is a great matter of concern that, tobacco plant is susceptible for cutworm damage during its life cycle eventually making inconsistent production. It causes a considerable damage to the tobacco plant particularly in the vegetative growth. The cutworm damage is more severe in the field level and in many cases it is present in the nursery level too. The Ceylon Tobacco Company has clearly discovered the demerits of the prevailing pest and chemical control has been playing a leading role for a long period of time as it has become more successful in its efficacies. The company commonly uses Chlorpyrifos 40 EC, a broad spectrum contact insecticide, which belongs to the chemical group of Organophosphate. Direct application of organophosphate insecticides including Chlorpyrifos is toxic and causes environmental pollution. In the environment, the organophosphate insecticide residues and the degraded ingredients pollute the soil, water, air and food. These compounds harm not only non beneficial insects but also beneficial insects, beneficial soil organisms and other animals including human beings. Therefore, usage of Chlorpyrifos is supposed to be phased out from the tobacco cultivations in the island wide. The objective of this study was to find a possible alternative to Chlorpyrifos to reduce environmental toxicity.
  • No Thumbnail Available
    Item
    Development of HACCP Plan for Ice Cream Manufacturing Process at MILCO (Pvt) Ltd.
    (Uva Wellassa University of Srilanka, 2011) Karunarathne, P.D.A.I.; Mudannayake, D.C.; Jayarathne, K.
    NOTE: see the PDF version The Hazard Analysis Critical Control Point (HACCP) approach for food safety moves away from testing of final product, and instead emphasizes on raw materials and process control. Control is taken out of the laboratory and in to the processing environment. HACCP provide a structured and systemic approach to the control of identified hazards, which may be biological (microbiological), chemical, physical or combination of the three. A Critical Control Point (CCP) is a raw material, stage, practice or operation within the process where a hazard has been recognized and steps are in place to eliminate, prevent or reduce the possibility of hazard occurring. The application of the HACCP system cover seven principles including identification of potential hazards associated with food production at all stages for processing, manufacture, and distribution until the point of consumption and preventive measures for their control (SLS 1173: 1998). The effectiveness of HACCP depends on the correct application of its principles, combined with other programs (prerequisite programs) such as Good Manufacturing Practices (GMPs), Good Hygiene Practices (GNPs), Standard Operation Practices (SOPs) and Sanitation Standard Operating Procedures (SSOPs). Ice cream, a milk-based product, is a good media for microbial growth due to high nutrient value, almost neutral pH value (pH 6 to 7) and long storage duration (Kanbakan et al., 2004). The quality of ice cream or any food product can be defined against a wide range of criteria, including for example, the chemical, physical, microbiological and nutritional characteristics. Food or dairy manufacturers aim is to ensure the safety and quality of their products which will satisfy the expectations of the consumers.
  • No Thumbnail Available
    Item
    Distinguishing Larval Instars of the Vegetable Leaf-Miner Liriomyza huidobrensis (Diptera: Agromyzidae)
    (Uva Wellassa University of Srilanka, 2011) Kaushalya, R.W.G.R.; Chandrasena, G.; Nishantha, K.M.D.W.P.
    Note: See the PDF Version The vegetable leaf-miner, Liriomyza huidobrensis (Diptera: Agromizidae) is a highly polyphagous species known to attack ten different plant families including economic crops and ornamental plants (Wijesekara, 1997). Larval parasitoid, Diglyphus iseae, has been introduced and has recorded higher levels of parasitism of the vegetable leaf -miner (Nugaliyadde et al., 2000). Diglypus isaea females oviposit on larger hosts but reject or feed on smaller hosts (Parrella, at al., 2005). Therefore, a need has arisen to develop an easy method to determine the correct time duration of different larval instars during the life cycle of vegetable leaf-miner, withouthelp of sophisticated methods. The Major objective of this study, was to identify a simple and easy method to distinguish different larval instars of the Liriomyza huidobrensis under glass house conditions and specific objectives were, to identify the different larval instars of Lirioniyza huidobrensis and to study the relationship between larval development time (in days) and larval instars of Liriomyza huidobrensis.
  • No Thumbnail Available
    Item
    Identification of Best Pasteurization Temperature – Time Combination for Retarding Microorganism Counts in Raw Cream as Ingredient of Butter: Approach to mprove Microbial Quality of Butter
    (Uva Wellassa University of Srilanka, 2011) Keenavinna, K.A.H.S.; Mudannayake, D.C.; Abesinghe, A.M.N.L.; Jayarathne, K.
    NOTE: see the PDF version This paper provides an overview of Best Pasteurization Temperature—Time Combination (BPTTC) for retarding microorganisms in raw cream as an ingredient of butter. BPTTC is an indicator of good quality raw cream as an ingredient of butter. Best pasteurization temperature—time combination is gaining the idea about good quality raw cream. The quality of raw cream is the most important factor in production of butter. If cream has an increase of microbial count it can't produce butter. In order to determine the quality microbial count is very important. In this study, different pasteurization temperature — time combinations were used to retard microorganisms count. This test uses microbial analysis of raw cream by using Total Colony Count (TCC) method and Yeast and Moulds count methods. When cream incorporates high intense heat fat separation occurs. It is not good for the production of quality butter. So when pasteurization temperature — time combinations needs to be critically monitored and identified its temperature — time combination them unhealthy pasteurization temperature — time range can be avoided. An increasing number of people are consuming raw unpasteurized milk. Enhanced nutritional qualities, taste, and health benefits have all been advocated as reasons for increased interest in raw milk consumption, however, science based data to substantiate these claims are limited. People continue to consume raw milk even though numerous epidemiological studies have shown clearly that raw milk can be contaminated by a variety of pathogens, some of which are associated with human illnesses and diseases (Oliver et al., 2009). Food spoilage is an enormous economic problem worldwide. Milk is a highly nutritious food that serves as an excellent growth medium for a wide range of microorganisms. The microbiological quality of milk and dairy products is influenced by the initial flora of raw milk, the processing conditions, and post—heat treatment contamination. Undesirable microbes that can cause spoilage of dairy products include Gram — negative psychrotrophs, coliforms, lactic acid bacteria, yeasts, and molds. In addition, various bacteria of public health concern such as Salmonella spp., Listeria inonocytogenes, Campylobacter jejuni, Yersinia enterocolitica, pathogenic strains of Escherichia coli and enterotoxigenic strains of Staphylococcus aureus may also be found in milk and dairy products (University of West Hungary, 2007). The hygienic production of milk is of the greatest importance for cream, because although most vegetative cells are easily killed by heat treatment, spores are not, and some types, such as B. cereus, can be a cause of spoilage (as well as failure in the
  • No Thumbnail Available
    Item
    Identification of Factors Affecting Farmers’ Satisfaction with Tea Extension Services in Yatinuwara Divisional Secretariat Division in Kandy District
    (Uva Wellassa University of Srilanka, 2011) Perera, M.G.A.; Dharmadasa, R.A.P.I.S.; Thalagoda, U.
    Agricultural extension is a specialized system of extension education relating to farmers. We have to effectively handle the information so as to attain our goal of achieving 3 Ps i.e., productivity, profitability and prosperity. In developing countries, it is not the lack of technologies which is a major setback, but the rate of transfer of technologies from the point of generation to the actual users. Thus, there is a vast gap between the knowledge generated and knowledge utilized. Further, it is not only the transfer of technology that alone modernized agriculture, but the adoption of technology and innovation which is equally important. As the result of knowledge gap and adoption gap, there exists considerable amount of yield gap. Many farmers are not able to realize the full potential. To obviate this, the farmers should be educated and technology should be taught to them. At present tea smallholders sector is the main producer of tea in Sri Lanka. It produces approximately 74 per cent of the total tea (TSHDA, 2007). Many extension programs were implemented at different periods by Tea Small Holders Development Authority (TSHDA) but certain limitations still exist in the tea small holding sector. The existing advisory services and extension services among small holders are inadequate. There is no opportunity to express any of their problems and to obtain advice or discuss with a responsible person. Through extension services they are providing knowledge, technology as well as some other facilities. Although they are providing those things they do not know in which extent farmers satisfied with their services. The effectiveness as well the farmers adoptions mainly depend on their overall satisfaction with the extension services. Therefore, identification of factors affecting for farmers' satisfaction with extension service is important to increase the effectiveness of the extension services.
  • No Thumbnail Available
    Item
    Influence of Vermicompost Technology on Solubility of Eppawala Rock Phosphate
    (Uva Wellassa University of Srilanka, 2011) Rathnayake, R.M.N.; Gunathilaka, R.P.D.; Senarathne, S.H.S.
    Note: See the PDF Version This study was conducted to determine the influence of vermicompost technology on solubility of ERP. Earthworms play a major role in vermicomposting. The most common type of earthworms used for vermicomposting is brandling worms (Eisenia foetida). Food is ingested through the mouth into a stomach (crop), which retains food and has the ability to expand. From there, food goes into the gizzard where sand and muscular contractions churn the food and increase the surface area. From there, food enters the intestine which has the ability to absorb food, then food exits through the anus. This final product consists of low power organic acids, like Malate, Oxalate, Citrate, etc. This low power organic acid is helps to increase the solubility of ERP. ERP is currently mined for use as a fertilizer for perennial crops such as tea, rubber and coconut. This is gives considerable value to the country because Phosphate deposits are non-renewable and dwindling resources in the world like fossil fuel. Also this is very economically important natural resource in Sri Lanka. Current production is 25 000 metric tonnes per year while reserves are 40 million metric tonnes. This saves nearly Rs 20 billion annually spent for importing fertilizer. This is important for providing the Phosphorus (P) fertilizer requirement, because P plays an important role in many physiological and bio chemical functions that are important to plants and animals. Major problem can be seen in ERP is the less solubility. The core bodies at Eppawala contain 42% P2O5 and citric acid solubility of different components varies from 4 to 6%. The parent rocks are mainly made up of calcite, dolomite and apatite, with lesser amounts of ilmenite, magnetite, pyrite, forsterite, phlogopite, enstatite, magnesite, diopside, tremolite and spine!. The Eppawala rocks are characterized by low silica (0.41%), high phosphorous (10.58%) and high strontium content (Gunawardena, 2003). Therefore in this study, an experiment was made to increase the availability of P by using vermicomposting.
  • No Thumbnail Available
    Item
    Investigating Variation of Microbial Biomass in Plantation Forests with Age
    (Uva Wellassa University of Srilanka, 2011) Premetilake, M.M.S.N.; Rathnayake, R.R.; Kulasooriya, S.A.; Perera, G.A.D.
    Note: See the PDF Version Soil organic carbon is the basis of sustainable agriculture and is important for chemical, physical and biological fertility. Consequently, carbon soil fertility could be improved more via sequestering. The role of microorganisms is important for carbon sequestration in soil compared to other factors. Thus, by increasing the activity of microorganisms we can increase carbon sequestration and soil fertility. Plantation forests were originally established in Sri Lanka to provide industrial timber and fuel wood. There are also other uses such as wind protection, bee keeping and oil extraction and moreover they provide invaluable ecosystem services. At present, sites available for reforestation in Sri Lanka are generally poor in nutrients and fertilizer application is required for better growth of seedlings. A novel approach of research at the IFS is the application of beneficial microbial consortia as biofilm biofertilizers for sustainable agriculture (Seneviratne et al., 2011). These are low cost and are eco-friendly. The shifts in composition and function of the microbial community in response to different stages of forest regeneration play an important role in determining rates of C changes (loss or gain) in the soil (Plante at al., 2005). Hence the long term goal of this study is to produce biofilm bio fertilizer for forest plantations to improve their yields. This would be more beneficial, less expensive and have no detrimental effects to the ecosystems. The biofilm bio fertilizer will be prepared using the microorganisms that have the capability of sequestering more carbon than the others. In this process, identification of the microorganisms and the factors affecting them is a crucial component. There are no studies conducted on this regard in Sri Lankan plantation forests yet. In the current study we investigated how the microbial biomass carbon (MBC) varies in Eucalyptus grandis forests in Sri Lanka with their age. Improved Carbon sequestration in forests would deliver better yields and would assist in minimizing climate change and support in obtaining foreign currency via carbon trading.
  • No Thumbnail Available
    Item
    Microbiological Quality Assessment of Raw Milk to Identify Sources of Contamination
    (Uva Wellassa University of Srilanka, 2011) Uduwerella, H.M.G.K.C.; Mudannayake, D.C.; Abeysinghe, A.M.N.L.; Jayasinghe, C.V.
    NOTE: see the PDF version Bogahawatta area is one of the major milk supplying area to Kotmale Dairy Products (Pvt) Ltd, Bogahawatta factory. One of the major challenges faced by Kotmale Products (Pvt) Ltd is the poor microbiological quality of the milk received at the factory. This research was carried out to find out the contribution of contamination sources for milk contamination in Bogahawatta area. Methodology Thirty small holder cattle farmers participated in this study. Farmers were selected using a simple random sampling method. Six samples (two milk samples and four swab samples) were collected from each farmer. Two milk samples (one sample received at the factory under chilling condition & other one received under room temperature) were received. Swab samples were collected from udders of cow, skin of cow, hands of farmer and milking bucket & lid. The time period for receiving milk from farm to the factory and temperature differences occurred during transportation period were recorded. The Total Plate Count (TPC) method was used to enumerate the total aerobic microorganisms present in the samples. Eosin Methylene Blue (EMS) Agar method and Violet Red Bile (VRB) agar method was used for enumeration of E. coli and Coliforms present in the samples, respectively. Karl Pearson Correlation Coefficient method and paired t-test was used to identify the relationship between the contamination sources and contamination of milk.
  • No Thumbnail Available
    Item
    Study on Factors Affecting the Farmers’ Decision to Practice Proper Safety Measures in Agro Chemical Applications
    (Uva Wellassa University of Srilanka, 2011) Indigahawela, H.I.S.W.; Mahindarathne, M.G.P.P.; Bandara, Layantha
    Food safety has become an important issue in the world today. There is a direct link between the inputs used in agriculture and the quality of food and safety aspects of food. Due to intensification of agriculture, farmers have no option but to use chemicals in controlling pest and diseases in agriculture Those chemical substances are called agrochemicals. Further, pesticides play a significant role by making agriculture safe from many dreadful pests (Abhilash and Singh, 2009). Globally, about 4.4 to 6.6 billion pounds (2 to 3 billion kilograms) of pesticides are being used every year, at a total cost of about $20 billion (Badruddin, 2010). During the past 50 years, the use of agro-chemicals in Sri Lanka has increased 30 times (Amarakoon, 2004). Farm workers and their families are exposed to pesticides through multiple pathways (Strong et al. 2008). Poisoning is a major health concern in Sri Lanka, where there is a very high morbidity and mortality from pesticide poisoning (Fernando, 2002). Further, pesticides and other agrochemicals have made some adverse effects on environment including, pollution of water, soil, destroying the beneficial organisms and air pollution. Accordingly, number of detrimental effects occurr due to the misuse of agrochemicals by the users and due to the lack of scientific knowledge about the agrochemicals and correct usage. Therefore, this research study was undertaken to identify the major factors which influence the farmers to make use of safety measures in agrochemical applications.