Research Symposium-2016

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Antagonistic Effect of Five Native Trichoderma Isolates on Economically Important Foliar Pathogens of Rubber
(Uva Wellassa University of Sri Lanka, 2016) Sandamali, P.K.N.N.; Chandrasena, G.; Fernando, T.H.P.S.; Silva, P.D.P.M.D.
Rubber foliar diseases play an important role in latex yield losses of rubber plantations in Sri Lanka. The frequent use of chemical fungicides to control causative pathogens leads to environmental pollution, hazardous to human and may lead to the development of new chemical resist pathogenic strains. Trichoderma species are the most widely studied bio control agent against many economically important plant pathogens. Hence, an attempt was made to investigate the antagonistic effect of five native Trichoderma strains on the plant pathogenic fungi; Colletotrichum spp., Corynespora cassiicola, Phytophthora spp. and Drechslera heveae. Foliar pathogens were isolated, identified and confirmed based on the symptoms, cultural and reproductive characteristics. Five Trichoderma strains isolated from different rubber growing soils in Sri Lanka were tested in vitro for their antagonistic effects against four foliar pathogens. The results obtained from dual culture tests showed that all five Trichoderma isolates effectively checked the growth of the four foliar pathogens. The test antagonists grew faster than the pathogen limiting their growth. Trichoderma isolate A was the best antagonist against Drechslera heveae, Corynespora cassiicola and Colletotrichum spp. showing percentage inhibition of 75.63 %, 51.34 % and 74.46 % respectively. Isolate B showed the best inhibition rate (70.99 %) against Phytophthora spp. All antagonists showed their lowest inhibition rates against Drechslera heveae. All the tested Trichoderma isolates showed antagonistic effects against four foliar pathogens under investigation. Therefore, the fungal strains can be used for further greenhouse and field studies to confirm the feasibility of using for the management of rubber foliar pathogens. Key Words: Trichoderma spp., Drechslera heveae, Corynespora cassiicola, Colletotrichuin spp., Phytophthora spp.
Antifungal Activity of Endophytic Fungal Species Isolated from Apple (Malus domestica)
(Uva Wellassa University of Sri Lanka, 2016) Naseefa, M.A.; Alakolanga, A.G.A.W.
Novel natural metabolites with a microbial origin are one of the most interested areas in Natural Product Chemistry. This study was aimed to investigate the antifungal activity of endophytic fungal species isolated from apple (Malus domestica). Endophytes, which have a microbial origin, reside inside tissue without causing apparent disease to host. Fresh apple samples from local supermarket, Badulla, were first surface sterilized to limit epiphytic fungi. Potato Dextrose Agar (PDA), supplemented with chloramphenicol (100 mg mL-I) was used to isolate a Penicilium sp. and a Chrysosporium sp. at pH 5.6. Isolated endophytes were cultured in potato dextrose broth for 14 days and extracted with hexane and ethyl acetate successively. Diluted (10 %) diethyl sulfoxide was used to prepare solutions of extracts and inhibition of fungal growth was determined using disc diffusion method at five different concentrations (1000, 2000, 3000, 4000 and 5000 ppm) against Alternaria sp. and Aspergillus sp. with 100 mg mL-1 flucanazole as positive control. Effective concentrations (EC,,, and EC90) were calculated for mean inhibition percentage. Aspergillus sp. growth was highly inhibited compared to Alternaria sp. by Penicllium extract. EtOAc extract of Penicllium showed high inhibition against (Minimum Inhibitory Concentration < 1000 ppm) Alternaria sp. than Crysosporium extracts (MIC 4572.2 ppm). Brine Srimp Lethality Assay (BSLA) was also carried out with 48h old naupali. Results were noted after 24 h. Penicllium sp. extract showed a high lethal toxicity (LC50 402.078 ppm) as they may produce excess of metabolites than Crysosporium sp. The observation of different antifungal activity of the two types of endophytic fungal extracts revealed the variations in chances and rates of producing secondary metabolites. With these results, it can be concluded that, apple endophytic fungal extracts can be used to control selected phytopathogenic fungal species, but the toxicity of extracts should be considered in case of food commodity. Keywords: Endophytic fungi, Fungal extract, Bioactivities, Malus domestica, Antifungal compounds
Antimicrobial Activity and Toxicity Effect of Adiantum Capillus-Veneris
(Uva Wellassa University of Sri Lanka, 2016) Abesingha, J.M.I.K.; Premathilake, S.N.
Medicinal herbs are important natural resources that can be used against various infections. Adiantum capillus-veneris has been used in traditional medicine for centuries against various infections. The objectives of the present study were to study the antibacterial activity against Staphylococcus aureus and the toxicity effect of A. capillus¬veneris. Leaf extraction of A. capillus-veneris was prepared using the Soxhlet apparatus with absolute methanol as solvent and then concentrated using a rotary vacuumed evaporator. Using a stock solution of 100 mg/mL four different concentrations of crude extracts were prepared (50 mg/mL, 25 mg/mL, 12.5 mg/mL, and 6.25 mg/mL) for the antibacterial test. Well diffusion method was employed to study the antimicrobial activity and inhibitory zone diameter was also measured. Absolute methanol was used as negative control. For the toxicity test crude extract was reconstituted using distilled water. A stock solution of 1000 1..tg/mL was prepared and 500 tg/mL, 100 ps/mL, 10 tg/mL and 1 lig/mL solutions were prepared using this solution. Zebrafish (Danio rerio) embryos were used as toxicological model and their coagulation, lack of somite formation, lack of detachment of the tail and lack of heart beat was used as the lethality indicators. The results indicated that methanol extract of the A. capillus-veneris have antibacterial activity against S. aureus and the Minimum Inhibitory Concentration (MIC) was 12.5 mg/mL (One way ANOVA, p<0.05 and Dunnett's test by 95% confident level). According to the Probit analysis the lowest LD 50 value received for toxicity test was 102 .tg/mL after 96 hours by 95% confident level. According to the results it could be concluded that leaf extracts of the A. capillus-veneris shows antibacterial activity against S. aureus at a very low concentration and they could be toxic with the increasing time duration. Keywords: Adiantum capillus veneris, Staphylococcus aureus, MIC, Zebrafish embryo, LD 50
Antimicrobial Effect of Seed Extraction of Cardamom (Elettaria cardamomum) on Mouth Odor Forming Bacteria
(Uva Wellassa University of Sri Lanka, 2016) Ekanayake, E.M.D.D.; Panagoda, G.; Premathilake, S.N.
Halitosis is an unpleasant odor that emanates from the oral cavity and Chlorhexidine included mouthwashes are a generally well accepted and popular way of dealing with halitosis. However most of these mouth washes merely provide a competing and temporary smell that is capable of masking the unfavorable malodor and may contain harmful chemicals such as alcohol and phenols. Elettaria cardamomum is used as a spice and ayurvedic medicine since ancient times and could be used in mouthwashes due to their pleasant aroma. In the present study, the antimicrobial effect of E. cardamomum seed extraction on mouth odor forming bacteria was investigated. Hot water extracts of E. cardamomum were obtained and concentration series (10000 ppm, 5000 ppm, 2500 ppm, 1250 ppm, 0 ppm) were prepared. Bacteria samples were obtained from pockets of oral cavity and posterior region of tongue and cultured on blood agar under anaerobic conditions. Antimicrobial activity test and odor test were carried out for the prepared concentration series. Ten replicates were used for one concentration in antimicrobial test and two replicates for odor test. This experiment was carried out using well diffusion technique and mean inhibition concentration (MIC) was determined based on the inhibition zones on the blood agar plates. Odor test was carried out using test panel of 8 members and a 0 ppm solution (blood agar broth) was used as a control for comparison after growing anaerobic bacteria. Cardamom seed extraction was added to other solutions according to the concentration and anaerobic conditions were given. A significant inhibition was observed on oral anaerobes and the effect was significantly increased with the increment of the concentration (Pearson correlation, 0.934, p = 0.000). A significant odor change was observed when compared with the control (p = 0.000) and 10000 ppm and 5000 ppm did not show any significant odor (One way ANOVA, Tukey Multiple Comparison Test). According to the results it can be concluded that E. cardamomum has antimicrobial effect on odor forming anaerobic bacteria and 5000 ppm could be identified as the MIC of cardamom extraction for the inhibition of anaerobes which form halitosis. Keywords: Elettaria cardamomum, Odor forming bacteria, Antimicrobial activity
Antioxidant Properties in Four Cyanobacteria sp., Isolated from Fresh Water Bodies of Sri Lanka
(Uva Wellassa University of Sri Lanka, 2016) Hossain, M.F.; Ratnayake, R.R.; Meerajini, K.; Premetilake, S.N.; Kumara, K.L.W.
The aim of this investigation was to study the total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity, phycobiliproteins and active compounds in four cyanobacterial species, i.e., Oscilatoria sp., Lyngbya sp., Microcystis sp. and Spirulina sp. isolated from fresh water bodies of Sri Lanka. Water sample was collected from different fresh water bodies representing two climatic zones of Sri Lanka that is dry zone and wet zone and was filtered through 20 p.m planktonic net. The retentiate was cultured in BG11 and GO media recommended for cyanobacteria. Frequent sub culturing was carried out to isolate uni-algal culture. Isolates were identified morphologically under microscope (40X magnification). In the present study, Lyngbya sp., showed highest TPC (5.02+0.20 mg/g), TFC (664.07+19.76 mg/g) and total phycobiliproteins (127.01 mg/g) value. The ferric reducing antioxidant power (FRAP) was recorded highest in Oscillatoria sp. (39.63+7.02) whereas the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity was also reported the highest in Oscillatoria sp. (465.31+25.76) followed by Lyngbya sp. (248.39+11.97). In FTIR spectroscopy Lyngbya sp. does not show any N-H stretching band which is ultimately responsible for the inhibition of antioxidant activity. The study revealed that Lyngbya sp. and Oscilatoria sp. can be an excellent source for food, pharmaceutical and other industrial use. Keywords: Cyanobacteria, Total Phenolic Content (TPC), Total Flavonoid Content (TFC), DPPH, FRAP, Antioxidant, Phycobiliproteins
Arsenic Removal from Water by Using Rice Husk Ash
(Uva Wellassa University of Sri Lanka, 2016) Edirisinghe, N.P.; Premachandrd, B.A.J.K.; Jayasuriya, C.K.
Arsenic is a toxic heavy metal present in water in organic and inorganic forms. It is highly toxic in its inorganic form. Long-term exposure to inorganic arsenic, mainly through drinking water, can lead to various health issues. The current research focuses on removing arsenic from water by the adsorption method using Rice Husk Ash (RHA). Particularly, RHA was used to check its suitability for arsenic removal since it will enable a value addition to the agricultural by-product. Rice husks were washed, dried and ground and then separated into different particle sizes using sieve analysis. Ashes from the rice husks were produced using a muffle furnace at 5 different temperatures as 300 °C, 400 °C, 500 °C, 600 °C and 700 °C. The resulting ashes were used as the absorbent in the columns through which 75 ppb arsenate solutions were passed. The experiments were carried out to determine the effects of particle size, charred temperature, pH and the use of RHA treated with phosphoric acid. Amounts of arsenic adsorbed were determined by using Atomic Absorption Spectrophotometry. Maximum adsorption was observed for RHA with particle sizes in the range (150 -500) 1.1.111 and the lowest for RHA with particle sizes in the range (125 -150) p.m. This result is deviated from the expected results. Theoretically, adsorption should be higher for small particles due to larger surface area. The maximum adsorption occurs at a charred temperature of 600 °C. Decreasing adsorption efficiencies after pH 7.0 for untreated RHA and after pH 7.5 for treated RHA were observed and it could possibly be due to the adsorption of more hydrogen ions due to high ion migration rate and high ion concentration. However, further investigation is required to study the effect of pH on the adsorption of arsenate by untreated and treated RHA. Keywords: Water, Purification, Arsenic, Adsorption
An Artificial Neural Network Model for Rainfall Prediction on the Basis of Agro-ecological Regions (AER) in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2016) Surin, A.A.D.; Wimaladharma, S.T.C.I.
There are many studies done for testing the capability of rainfall forecasting using artificial neural networks. In Sri Lankan context, this study presents another model that uses Agra Ecological Regions as the basis instead of currently popular administrative districts. An Agra Ecological Region represents a particular combination of climate, soil and relief, so this study tries to find out the advantage and accuracy of giving a weather report per each Agra Ecological Region. For the purpose, two locations from WL4 region, Bandaranayaka International Airport (UM) and Galle weather station (WM043495) were considered. The Artificial Neural Network was trained using 10 years of daily data from each selected station using split-sample method. The accuracy of predicting rainfall probability, rain or non-rain status is tested. Selected Artificial Neural Network is a pattern recognition, feedforward based neural network, which uses hyperbolic tangent function as the transferring function and back propagation method as the training algorithm. Mean temperature, mean dew point, mean humidity, mean sea level pressure, mean visibility and mean wind speed were selected as inputs for the neural network. According to the binary classification strategy, the status of each day was defined as rain or non-rain. Mean value of each weather parameter was compared with each locations, and there were no significant difference between the actual values and the predicted values. The estimated error rate of making predictions using the proposed model was less than 35%. According to the results obtained, this model tends to be giving more precise results compare to the district based weather forecasts. Keeping several classification parameters as targets and using more observatory points are the recommendations to improve the accuracy of the results of this forecasting model. Keywords: Artificial Neural Network, binary classification, rainfall forecasting, climate, pattern recognition
The Aspects on Reproductive Biology of Blue Swimming Crab Portunus pelagicus, (Linnaeus, 1758) in Mannar Area
(Uva Wellassa University of Sri Lanka, 2016) Abeygunawardana, A.P.; Jayamanne, S.C.
Blue swimming crab fishery is a newly emerging export oriented fishery in North and North-Eastern provinces of Sri Lanka. Since the exploitation is heavy in these areas establishment of management strategies are important for sustainability of the fisheries. Hence the aspects on reproductive biology such as maturity stages, pre-spawning and post spawning fecundity, size at first maturity and gonadosomatic index of the Blue swimming crab (Portunus pealagicus) in Mannar area were studied during the period, May to July, 2015. The fecundity was estimated using Gravimetric method. Six ovarian development stages, immature, developing, early Mature, late mature, ripe and spent were identified in non ovigerous crabs and five ovarian development stages, light yellow ovaries, pale yellow ovaries, pale orange ovaries, black colour ovaries and grey colour ovaries were identified in ovigerous female crabs. The size at first maturity was determined as 57.5 mm carapace length and carapace width 113.50 mm. The pre spawning fecundity estimates ranged from 105874 to 516000 in the crabs of 133 mm to 158 mm carapace width. The post spawning fecundity estimates ranged from 537600 to 1739000 in the crabs of 121 mm to161 mm carapace width. The pre spawning fecundity and the post spawning fecundity showed positive correlations with the carapace width, carapace length and the body weight (P<0.01). The Gonadosomatic Index of the female crabs varied from 0.94+0.0208 in immature crabs to 30.6 +0.8048 in matured crabs. More than 80 % of the catches contained immature crabs while percentage of ovigerous females was 8%. High exploitation of immature crabs and ovigerous crabs may have serious impacts on the sustainability of the Blue swimming crab fishery in future. Keywords: Carapace length, Pre spawning fecundity, Post spawning fecundity, Reproductive biology.
Assessing Adoption of Organic Pepper Cultivation in Kandy, Matale and Kegalle Districts
(Uva Wellassa University of Sri Lanka, 2016) Yallarawa, Y.S.M.M.P.; Alwis, L.M.H.R.; Wickramasinghe, K.
Increased domestic and international demand for organic products, along with environmental and safety issues have stimulated policymakers and governments in some parts of the world to provide incentives for converting from conventional to organic farming. Sri Lankan agriculture industry is developing its potential to address it. The country is trying to be a quality organic supplier to the world market. This study was conducted to investigate the level of the adoption of organic pepper farming and to identify the factors affecting on intension to conversion of conventional cultivation of pepper to organic cultivation of pepper in Kandy, Matale and Kegalle districts. The data used in the study were collected from a sample of both organic and conventional farmers. A total of 126 respondents were selected from the three different cultivated areas to obtain main objective and 72 respondents were selected from the three different cultivated areas to obtain second objective. Probit model was used in this study to categorize the organic farming into adoption and non-adoption. Age of the household head, experience, land area and number of awareness sources have significant effect on the adoption of organic pepper farming. Gender, age of the household head, primary education, attitude on cost of non-organic farming and price per one kilogram of pepper have significant effect on intension to conversion. Forty three percent of farmers in the study area have adopted organic cultivation of pepper. Assessing the intension to conversion, conventional farmers show some potential for converting to organic practices. Seventy eight percent of the farmers in the study areais having an intension to convert their farms into organic. The institutions related to organic farming are very useful in providing information about organic farming. Government agencies, extension and research institution should play a vital role to strengthen the awareness and advantages of organic farming. Keywords: Organic farming, Intension to conversion, Adoption, Probit model
Assessment of Microbiological Quality in Set Yoghurt Production Line at a Commercial Dairy Processing Plant
(Uva Wellassa University of Sri Lanka, 2016) Ranasinghe, T.D.W.; Madakumbura, M.G.C.S.; Abeyrathne, E.D.N.S.
A study was conducted to find out microbial contaminations, sources and preventive measures in the set yoghurt production line in Pelwatte Dairy Industry Limited (PDIL) at Buttala. Samples were collected at all the processing steps and from raw ingredients and UV splash water. Swab samples were collected from processing vats, CIP tank and permanent workers' hands. Air samples were taken from Air Condition (A/C) plant, table fans and yoghurt filling area. Quality of samples was assessed using microbiological (total colony count, Coliform, yeast and moulds) properties. Pasteurized yoghurt mixture samples (sorbate added mixture, culture inoculated mixture and filling mixture) were detected after an effective pasteurization process (92°C, 5 minutes). Further analysis of contamination points showed the presence of yeast and mouldin the air samples, UV splash water and swabs of the exposed processing vats such as balance tank and CIP tank. However, the enclosed processing vats such as mixing vat and filling vat were free from yeast and mould after CIP cleaning using sterilized UV splash water (100°C, 2 minutes) as final rinsing agent. Balance tank was always exposed to the outer environment during manufacturing process and culture inoculation vat was opened twice after CIP. Yeast and mould were detected in both vats. Yeast and mould were consistently detected in air samples and simultaneously the swabs of permanent workers' hands. Table fans were close to workers and filling area. Hence, it can be concluded that air obtained from A/C plant and fans was the contamination source of yeast and mould. Microbiological quality of set yoghurt can be improved by using clean and proper ventilation, minimizing the exposure of processing area to outer environment and frequent cleaning of air filters in A/C plant, while maintaining the basic manufacturing steps. Keywords: Set yoghurt, Microbial contaminations, Sources, Air
Assimilation of Phosphate Fertilizer derived from Eppawala Rock Phosphate on the Vegetative Growth of Corn (Zea mays L.)
(Uva Wellassa University of Sri Lanka, 2016) Rathnayake, R.M.S.R.; Wijesekara, K.B.
Phosphorus is one of the most important macronutrient in plant nutrition and wellbeing. Repeated cultivation has caused drastic depletion of nutrients in agricultural lands necessitating routine addition of costly commercial fertilizers to crops. Rock phosphate deposit at Eppawala Sri Lankan, provides a rich source of phosphorus from which phosphate grade fertilizer could be produced by the acidulation with con. HC1. However, pH of the fertilizer is needed to be adjusted to plant tolerable levels to reduce acid toxicity. This research used CaO to adjust pH of rock phosphate derived fertilizer enabling rapid assimilation by plants. Approximately 100 g of the acidified product was added with a predetermined quantity of 3. 7 g of lime to adjust the final pH value to 6.02. XRF analysis was performed to identify the elements of the final fertilizer mixture before and after CaO addition. A pot experiment was performed to determine the assimilation of newly developed fertilizer by corn plants. The experiment was arranged in a complete randomized block design with five treatments and 180 experimental units. Treatments were: Ti- Pants without any amendments, T2-Plants with commercial fertilizers excluding phosphates, T3-Plants with commercial fertilizers including phosphate, T4-Plants with commercial fertilizers+developed fertilizer without pH adjustment, T5-Plants with commercial fertilizers+developed fertilizer with pH adjustment. Plant height, root surface area, biomass at flowering and leaf chlorophyll content were measured to determine the plant performance after fertilization. X-ray fluorescence (XRF) analysis revealed that developed fertilizer contained 11.4% P2O5, 16.5% MgO, 14.9% K20 and 24.3% CaO as major constituents while providing plant with some important micronutrients such as, Mn, Fe, and Zn. Addition of lime was not only resulted in increasing the of pH to plant tolerable levels but also eliminated Cl and some heavy metal contaminants like As and Rh. Growth performance of T5 plants indicated that phosphate from developed fertilizer had readily assimilated by Corn plants. However, the commercial triple superphosphate used to supplement T3 plants showed significantly higher (p=0.00) performance over T5 plants. T4 plants supplemented with fertilizer without pH adjustment died prematurely while T5 plants showed normal growth suggesting pH adjustment with CaO was effective. Key words: Rock phosphate, Phosphat fertilizer, pH adjustment, Plant assimilation
Automated Dispensary Mechanism for Government Hospitals
(Uva Wellassa University of Sri Lanka, 2016) Rupasinghe, C. J.; Thambawita, D.R.V.L.B.
Dispensing medications in a hospital is a time consuming operation. In usual practice, the pharmacist need to dispense tablets and capsules with a simple tray and spatula. A typical hospital dispensary has only a few number of pharmacists causing long patient queues, the situation can be commonly experienced in most of the government hospitals in Sri Lanka. This inspired to introduce the concept of automated medication dispensing for Sri Lanka. This research introduces an automated solution for medication dispensing in outpatient dispensaries. The key objective of the study was to reduce the time consumption of drug dispensing. A desktop application was developed to generate prescriptions and an automated drug dispensing has been implemented. The solution comprised of a software artifact and an electronic hardware unit. The software tool is connected with a fingerprint reader which is used for patient registration. Patients can register with the system when he or she comes to the outpatient dispensary at first time. The pill container has three main parts: initially the upper part of the pill container is fed with tablets to be counted, and the middle part for hold some amount of pills to fetch the rotating pill catcher. Then the lower part called rotating pill catcher for catch pills one by one and carry them to the exit gate of the pill container. This pill catcher rotate with the help of a stepper motor. An infra-red sensor keeps counting the number of pills which are being released through the exit gate. If the count is equal to number ofpills in the prescription, the motored mechanism will stop. Furthermore, two mechanisms were adopted for the tablets counting process. The first mechanism is based on a vertically rotating wheel which have several openings to catch one pill at one time. The second mechanism is based on a horizontally rotating round plate which have openings to catch one pill at one time. The process which is based on the horizontally rotation plate has achieved a considerably accurate pill count by compared to the vertically rotating wheel version. It was noticed that the vertically rotating wheel model was blocked most of the times because it cannot hold exact one pill at a time. Therefore horizontally rotation plate can be introduced for as an effective pill counting mechanism. Keywords: Pill catcher, Pill fetcher, Infra-red sensor
Automated Oil Pumping System for Sewing Machines
(Uva Wellassa University of Sri Lanka, 2016) Jayasundara, J.M.S.M.B.; Samanthilake, U.D.
Various types of sewing machines are available in the apparel industry. On the surface of such a machine, there is a movable contact that touches with any other point, which need to be lubricated. Different amounts of lubricant oil are carried from the oil bath of a sewing machine and this oil should be changed time to time and usually that is done by mechanics manually. The manual way of the oil changing is a time consuming task and may require some special skills. An automated oil changing system such as implemented in this research has the ability to overcome the issue. This system consists of an oil filling system that can be operated with push buttons on a panel, as the inputs. The Arduino platform acts as the control unit while an oil pump is considered as the output. As a feature of this automated oil changing system, the oil bath can be filled automatically by pressing the buttons according to the type of the sewing machine. Different buttons available on the system enable the users to select the appropriate type of sewing machines. When the relevant push button is being pressed, input signal is received by the Arduino. The oil pump will turn on through the relay device with respect to the controlling program that has been uploaded to the Arduino. After filling the oil bath to the standard level, oil pump will turn off automatically. By using the automated system, the efficiency of the sewing machine maintenance process has significantly improved. As a result of this study, the best results were obtained in double needle machine based on the factorial analysis with multiple comparisons. Keywords: Arduino, Sewing machine, Sewing machine maintenance
Awareness of and Adoption to the Recommended Management Practices of Big Onion Growers (Case Study in Dambulla D.S. Division)
(Uva Wellassa University of Sri Lanka, 2016) Nanayakkkara, D.N.; Kaliyadasa, P.E.; Amarakoon, A.M.C.; Padmini, S.M.P.C.; Chandrasiri, J.K.M.D.
Big onion is considered as an important cash crop in Sri Lanka. Within few decades big onion production has increased significantly along with the increasing demand for consumption. Though the production has increased, productivity is not satisfactory as average of 17 MT/ha where the potential productivity lies at 30-37 MT/ha. Therefore, it is imperative to study the knowledge level of the farmers and their adoption behavior regarding the recommended cultivation practices. Sixty five big onion growers who have not less than 5 years of big onion farming experience were interviewed in Dambulla D.S. division. Sample was selected randomly and data were collected using structured questionnaire. Total of 17 DOA recommended practices were considered initially but only 7 management practices were shown correlation with the level of awareness and adoption status. Therefore those practices viz use of recommended varieties, nursery sterilization procedure, seed treatment, spacing, seedling treatment, pre emergence herbicide application, correct harvesting stage and providence of optimum storage conditions were considered for further analysis. Results reveal that awareness on pre emergence herbicides and optimum harvesting stage has reported comparatively higher and they are 98.5% and 89% respectively. When considering the adoption, 76.9% of the respondents reported that they did not keep spacing while transplanting. Though the respondents have high awareness on optimum harvesting stage, only 27.7% well adopted to practice it. Factors affecting adoption are analyzed by using a multiple linear regression model and 5 factors were found significant. Respondent's age and off farm employment negatively affect the adoption level whilst education level, big onion farming experience and community leadership have no impact on adoption. According to the results it can be suggested that, though the farmers have sufficient knowledge on pre emergence herbicide application, correct harvesting stage and optimum storage conditions, majority has not at all adopted to those practices. Ultimately, it causes serious market based issues. Keywords: Adoption level, Awareness, Big onion, Management practices
Can Diversity Indices Reflect the Forest Degradation Status? A Case Study of Hurulu Dry Forest Sri Lanka
(Uva Wellassa University of Sri Lanka, 2016) Medawatte, W.W.M.A.B.; Iqbal, M.C.M.; Ranwala, S.M.W.
The degree of dry forest degradation due to anthropogenic disturbance is not yet quantified and this impedes forest restoration interventions and conservation in Sri Lanka. This study investigates selected diversity indices in response to anthropogenic disturbance to assess the severity of disturbance in the Hurulu forest reserve. Three different disturbance regimes (Un-Disturbed [UD], Moderately-Disturbed [MD] and Highly-Disturbed [HD]) were considered based on previous maps of the forest reserve and by conducting a reconnaissance survey. Sixty randomly selected plots (10 m X 20 m) were placed in the above disturbance regimes. In sampling plots, all living trees >1 cm was identified and enumerated by species. Tree species diversity was measured as different diversity and evenness indices such as Shannon's, Simpson's, Berger (reciprocal Berger-Parker diversity), Pielou's evenness and Simpson's evenness index. These indices were transformed to log and compared using one-way ANOVA. There were significant differences among disturbance groups regarding all the indices (P<0.05) excluding Pielou's evenness index (P>0.05). Significantly high mean Berger diversity index value (P<0.05) was observed at UD (3.70±0.01) and lowest at the more disturbed forests, i.e., MD (2.63±0.03) and HD (2.43±0.04). Though mean Shannon and Simpson diversity indices for UD showed significant differences (P<0.05) with HD, they did not show such differences with MD. Mean Simpson's evenness index for UD showed no significant differences (P>0.05) with HD forest. Though mean Shannon and Simpson diversity indices for UD showed significant differences (P<0.05) with HD, but not showed such differences with MD. Mean Simpson's evenness index for UD showed no significant differences (P>0.05) with HD. Though Shannon and Simpson diversity indices are sensitive to high disturbance, best diversity indices to explain differences between Un-disturbed and disturbed forests were Berger diversity index showing its highest value and high sensitivity in those dry forest which are in an undisturbed condition. Key words: Forest degradation, Anthropogenic disturbance, Dry forest
Characterization of Conserved Germplasm of Pungent Chilli Landraces (Capsicum chinense Jacq)
(Uva Wellassa University of Sri Lanka, 2016) Jayathissal, K.A.M.Y.O.; Alwis, L.M.H.R.; Kannangara, K.N.
Morphological and agronomical traits are widely used to study the diversity in Capsicum species, to determine the relationship between various species and to develop an identification key. Capsicum chinense Jacq ("Nai Miris") species are still not properly characterized as the attention has been directed to Capsicum annum species. Hence present study was undertaken to explore the morphological and agronomical diversity of Capsicum chinense Jacq at Regional Agricultural Research and Development Centre, Makandura, low country intermediate zone (IL,a). Thirty three morphological traits and fourteen agronomical traits considered for 48 accessions germinated from 112 Capsicum accessions. Accessions were collected from Plant Genetic Resource Centre and chilli breeder, Mr. K.N. Kannangara. Characterization was based on descriptor for Capsicum produced by PGRC. Based on the results of48 Capsicum accessions, there were no duplicated accessions within the studied accessions. The traits that largely contributed to the variability within and between the accessions included corolla colour, anther colour, fruit colour at intermediate stage, fruit colour at mature stage, fruit shape, mature leaf length, mature leaf width, number of days for flowering, number of days for fruiting, fruit length, fruit wall thickness, fruit weight and 1000 seeds weight. Cluster analysis showed that there are three major clusters in germplasm collection of Capsicum. One major cluster consisted with 23 accessions of pungent chilli having useful and most common characteristics such as: annular constriction of calyx and clusters of flowers or fruits at node, which are exclusively found in the Capsicum chinense Jacq accessions. The twenty three accessions divided in to seven sub clusters and showed wide genetic diversity that exists in Capsicum chinense germplasm. Keywords: Morphological traits, Agronomical traits, Capsicum chinense Jacq, Cluster analysis, Genetic diversity
Characterization of Hydroxyapatite Derived from Sri Lankan Rock Phosphate for Biomedical Applications
(Uva Wellassa University of Sri Lanka, 2016) Chrishanth, M.; Wijesekara, K.B.
Hydroxyapatite (Ca,,,(PO4)6(OH)2, (HA) is an important inorganic biomaterial with a structural similarity to minerals of human bone and teeth. HA is widely used for repairing bone defects in dental and orthopedic sites as filler or as a coating to promote bone ingrowth into prosthetic implants. Rock phosphate deposit at Eppawela Sri Lanka provides a rich source of chlorofluoroapatite which could be converted to HA. Conversion of apatite into hydroxyapatite was done by mixing 19.9 g of calcium hydroxide with 250 g of apatite powder (3:1 ratio) with constant stirring to achieve a homogeneous mixture, followed by high temperature sintering at 1000°C for 3 hours. Sintered HA was subjected to physical and chemical analysis to confirm successful conversion of apatite to HA and to establish its suitability in biomedical applications. Test conditions used were similar to pH and temperature changes that may occur in oral cavity of humans. FTIR spectroscopy patterns confirmed the formation of a hydroxyl group to crystalline phase of HA. FTIR spectra showed a stretching bond at 3420 cm' which indicates the presence of HA. Peaks at 1030 to 1085 cm' corresponds to symmetric stretching mode of PO43- while peak at 564 cm' indicates the bending mode of NV-. The large separation bands indicate the presence of crystalline phase. Solubility (% weight loss) was high in pH 4 for all three temperatures tested (55°C, 30°C and 5°C) indicating acidulation of HA at low pH. At higher pH, solubility was insignificant. The % weight loss correlates with the amount of Ca2+ and PO43- ions dissolved in the solution. The calculated thermal expansion coefficient of HA was 17.436x 10-5 °C-' which is x3 higher than that of human teeth (i.e. 6.603x10-5 °C-'). Compressive strength of synthesized HA pellets was between 19-23 MPa which is lower than the expected value of 100 MPa of natural bones. Conversion method adapted in this study is simple and easy compared to popular Sol-gel method. Synthesized HA was stable at high pH between 5°C to 55°C. Lower compressive strength and high thermal expansion coefficient obtained with synthesized HA suggests that the conversion method needs optimization to make the product suitable for biomedical applications. Keywords: Rock Phosphate; Hydroxyapatite; High temperature sintering, Biomedical applications
A Comparative Study of Phytochemical, Proximate and Mineral Compositions of Different Selections of Dried Goraka (Garcinia quaesita) Fruit Rinds in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2016) Jayasundara, K.K.I.; Wijesinghe, W.A.J.P.; Liyanage, T.
Goraka (Garcinia quaesita) is a multi- purpose and endemic tree species bearing economical important edible fruits. Objective of this study was to investigate the comparative phytochemical, mineral and proximate contents between four Garcinia quaesita selections namely Ovilikanda I, Ovilikanda II, Gasnawa and Aranayaka I that were cultivated under similar agro climatic conditions in the nursery farm of Department of Export Agriculture, Gasnawa. Standard Analytical procedures were followed to analyze phytochemical, mineral and proximate compositions. The phytochemical analysis suggested a quantitatively higher percentage of hydroxycitric acid content in Aranayaka I selection than other selections. Flavonoid content was significantly (p < 0.05) higher in Ovilikanda I than other selections. The results of proximate analysis revealed that Ovilikanda I was richer in acid insoluble ash and dry matter while Gasnawa selection exhibited greater amounts of crude fat and crude protein. Significantly (p < 0.05) higher amounts of crude protein and nitrogen contents were found in Aranayaka I selection while Ovilikanda II selection exhibited the highest total ash content. In mineral analysis, significantly higher amount of magnesium was observed in Ovilikanda I, while Ovilikanda II contained highest amount of phosphorous. Gasnawa selection contained significantly (p < 0.05) higher amount of potassium and Aranayaka I contained higher amount of sodium than the other selections. Keywords: Goraka, Garcinia quaesita, Phytochemical analysis, Fruit rind, Mineral
Comparative Study of Proximate Composition of Palmyrah Pinattu and Flour (odiyal, Boiled odiyal)
(Uva Wellassa University of Sri Lanka, 2016) Srikantharasa, S.; Mahilrajan, S.; Wijesinghe, W.A.J.P.; Bandara, S.M.I.P.G.
Palmyrah (Borassus flabellifer) palms can be considered as a gift of nature as they contribute wide range of vital products for human diet and existence. Among palmyrah products fruit and flour are highly utilized by local population. Fruits are mostly used as fresh, because of its perishable nature it is traditionally preserved as dried fruit pulp leather called as pinattu. Palm produces two types of flour such as odiyal (Dried tuber) and plukodiyal (boiled and dried tuber) flour. In this study the proximate composition of palmyrah pinattu and flour were evaluated. Samples were collected from the three different branches of Palmyrah Development Board and used for the analysis.There were no significant different between moisture content of the boiled odiyalflour [11.66± (0.001)] and odiyal flour [10.66± (0.001)] while pinattu showed [16.6± (0.008)] %. Protein content of boiled odiyal flour [6.51±0.062] and odiyal flour [6.7813± (0.06)] were significantly higher when compared with pinattu [2.23± (0.062)] %. As well fat content of odiyal flour was 0.43±0.013 g/100g and that was significantly higher than boiled odiyal flour and pinattu. Significantly higher amount of ash was observed in pinattu [0.04±(0.001)]when compared with flour. Boiled odiyal flour [7.13±(0.18)] contained significantly higher crude fiber content than odiyal flour [4.49±(0.15)] and pinattu [5.06±(0.01)] g/100g. Carbohydrate content was significantly higher for odiyal flour [77.59±(0.5)] when compared with pinattu [75.91±(0.61)] and boiled odiyal flour [74.37±(0.65)] g/100g. This study was suggested that proximate composition of pinattu and flour were varies and which were good source of fiber and protein. Keywords: Boiled odiyal flour, Palmyrah, Pinattu
Comparison of Meat Quality Traits of Scalded and Non-scalded Broiler Chicken Meat
(Uva Wellassa University of Sri Lanka, 2016) Iromi, S.T.T.; Jayasena, D.K.D.D.
The aim of this work was to investigate the physicochemical and sensory characteristics of scalded (SBC) and non-scalded broiler chicken (NSBC) breast meat. Six birds were randomly selected from the processing line of New Anthoney's Farms (Pvt) Ltd before and after scalding process which used as treatments. Proximate composition of breast meat of each bird was determined as outlined by ADAC (1995). Measurement of color was determined by using a colorimeter (CR-410, Konica minolta, NIC., Japan). Measurement of pH was determined by using a pH meter (PH700, Eutech instrument, Singapore). Cooking loss was determined by heating the samples up to 85°C for 30 min in a water bath (LWB-IIID, Daihan labtech Co.LTD., Korea). Analysis of variance was conducted by the (ANOVA) and the General Linear Model using SAS program version 9.1 (SAS, 2002, SAS Institute, Cary, NC, USA). Mean Separation was analyzed by Duncan's multiple range tests at P<0.05. SBC contained higher protein but lower fat content than NSBC and no differences in ash and moisture content. Lower fat content in SBC is, dissolve the fat in hot water used in scalding tank. L*, a* and b* values were not significantly difference (p<0.05) between NSBC and SBC. Higher pH values were shown by NSBC and no any significant difference of cooking loss in NSBC and SBC. In higher temperature, glycolytic potential will increase and more lactic acid will produce. That can be the reason for the high pH value in NSBC. It will reduce the ultimate pH of the carcass. Based on the results of the sensory analysis, there was a significant difference (p<0.05) in overall acceptability. Reason for this difference can be, a niche market (Buhari Hotel) existing for NSBC. Keywords: Scalded, Broiler, Non-scalded, Physicochemical, Sensory

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