International Research Symposium of UWU-2018

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Analysis of Chemical Composition and Oil Yield of Cymbopogon nardus and Cymbopogon winterianus in Thanamalwila Area
(Uva Wellassa University of Sri Lanka, 2018) Gamage, T.G.K.M.; Ariyasinghe, H.A.E.N.; Alakolanga, A.G.A.W.
Citronella (Cymbopogon nardusand Cymbopogon winterianus) plant is a perennial crop which is used to extract citronella oil as a commercial product. Citronella is cultivated in Southern coastal area of Sri Lanka, mostly in Matara and Hambantota districts. Citronella cultivation is recently started in Thanamalwila area. Variety, climatic and soil condition can affect the yield and chemical composition of citronella oil. Objective of this study was to analyze and compare the oil yield and chemical composition of two species cultivated in Thanamalwila area to select the best species for oil extraction. Steam distillation technique was used to extract the citronella oil and gas chromatography-mass spectrometry (GC-MS) was followed to analyze the chemical composition. It was found significantly (P < 0.05) higher percentages of Citronellol (7.14%), Citronella! (9.02%) and Geraniol (16.01%) in Cymbopogon nardusthan in Cymbopogon winterianus in which the respective values were 4.68%, 4.81% and 6.3%. There were no significant differences between two species with respect to their Camphene, Limonene and Borneol contents. The oil yield of Cymbopogon nardus was significantly (P < 0.05) higher than that of Cymbopogon winterianus. Therefore, as far as the oil yield and chemical composition of oil are concerned, Cymbopogon nardus is the best variety to cultivate in Thanamalwila area.
Analysis of Pesticide Residues in Fruits and Vegetables exported to the European Union and determining the effect of Chlorine Treatment on Diazinon Residues
(Uva Wellassa University of Sri Lanka, 2018) Mallikaarachchi, M.A.S. K.; Magamage, M.C.; Premathilake, K.G.; Weerawansha, A.N.R.
Presence of pesticide residues in agricultural commodities can cause acute and chronic toxicities on humans.The objective of this study was to develop a monitoring programme to regulate the pesticide usage of farmers and to determine the effect of chlorine treatment on diazinon residues of tomato and bean samples. Two surveys were conducted to identify the malpractices of the farmers and exporters who cultivate and process the commodities, which are exported to the EU. A total of 98 samples of fresh fruits and vegetables were analysed for the presence of 66 active ingredients of pesticides. The quick easy cheap effective rugged and safe multi-residue extraction method was followed, using gas chromatography mass spectrometry. There were no malpractices were identified at farmer level while three malpractices were identified at exporter level. Analytical results revealed that only 26% of the samples were positive for pesticide residues. Pesticide residues above the European Union Maximum Residue Limit (MRL) were detected in 65% of samples among the contaminated. Multiple residues (2-3) were present in 11% of contaminated samples. Eleven pesticides were detected, of which 7 were insecticides, 4 were fungicides and no weedicides. Mostly detected active ingredients were profenophos and etofenphox, both of which were insecticides and carbendezim, a fungicide. The chlorine treatment had a significant effect on reduction of Diazinon residues in tomato (p = 0.024) and bean (p = 0.005) samples. The results confirmed the presence of pesticide residues in fruits and vegetables exported to the EU. Chlorine treatment at 150 ppm dosage could effectively reduce the residues of diazinon in tomato and beans.
Application of Gamma Irradiation as a Quarantine Treatment to Control Fruit Fly (Bactrocera dorsalis) Prevailing on Export Potential Mango Fruits in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2018) Madhushani, U.G.L.; Hewage, L.C.; Weerawansa, A.N.R.; Wijesinghe, W.A.J.P.
Fruit flies cause considerably serious damage to mango fruits by reducing quality and nutritional suffering. Among all the quarantine treatments, irradiation is unique as it is the only treatment used which does not cause acute mortality; instead, insects are prevented from maturing or are sterilized.Currently there are no any approved irradiation quarantine treatment doses for eggs of Bactrocera dorsalis. The objective this study was to determine the effective irradiation dose to control eggs of B. dorsalis.Export quality Tom EJC mango fruits which were artificially inoculated with B.dorsalis eggs were treated with 100 Gy, 200 Gy and 250 Gy Gamma radiation. The experiment was carried out in Complete Randomized Design with four treatmentsand a control with three replicates.Each replicate included three fruits where approximately 50 eggs were introduced to each fruit. After exposing to gamma irradiation, there was no any adult emergence but some of eggs were developed into larvae and pupae. No significant difference was observed in titratable acidity, brix, colour, moisture content, pH, textureand water activity of irradiated fruits compared to untreated fruits. Therefore, selected three gamma radiation dosages can be declared suitable for reducing the development of B. dorsalis eggs and it does not cause any quality defects to the fruit.
Assessment of Avocado as a Potential Alternative Host Plant for Colletotrichunigloensporioides Causing Nutmeg Leaf Fall Disease
(Uva Wellassa University of Sri Lanka, 2018) Rupasinghe, P.S.A.; Wijekoon, W.M.R.W.B.; Chandrasena, G.; Silva, P.D.P.M.D.
Nutmeg(Myristicafragrans) is an important Export Agricultural Crop grown in Sri Lanka. It is mainly distributed in Kandy and MataleDistricts. Nutmeg Leaf Fall Disease (NLFD) was reported as an economically important disease in 2004 and Colletotrichumgloeosporioideswas identified as the causal organism of the disease. Avocado, mix cropped with nutmeg in Kandyan home gardens reportedsome diseases with the same causal organism as that causing NLFD. Therefore, the study was conducted to assessthe potential of avocado being an alternative hosttothe causal organism of NLFD and to upgrade the existing Integrated Disease M a na ge me nt pra cti ce s of NL FD. T he c ross i nfe ct i on potentialbyC.g/oeosporioidesisolated fromnutineg leaves and avocado fruits were tested through cross inoculation between healthy avocado fruits and healthy nutmeg seedlings.Pathogenicity was quantified calculatingPercent Disease Index (PDI) and Virulence Index (VI). The results revealed that there is a possible disease causing ability of both crops by each isolated strains of C.gloeosporioidesin both ways. The calculated PDI values were 15% and 55% and VI values were 20.2% and 25.8% for nutmeg and avocado, respectively. Thus, avocado plant was identified as a potential alternative host for the causal organism of NLFD. Therefore, the field sanitation of avocado plants must be recommended as an additional measure, where nutmeg and avocado are grown together to avoid spreading of NLFD as a long term disease management strategy.
Assessment of Environmental Impact of Selected Herbicides Used in Rice Farming in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2018) Bandara, R.M. U.S.; Dissanayaka, H.M.M.K.K.H.; De Silva, Y.M.S.H.I.U.; Dissanayake, D.M.C.B.; Witharana, D.D.
Environmental hazard of pesticides are estimated using Environmental Impact Quotient (EIQ) method. Commonly used 12 herbicides were selected for the assessment of EIQ in order to know what the eco-friendly herbicides to be used. EIQ values were calculated for one hectare using EIQ calculator which is available online at http:// www. nysipm. cornell. edu/ EIQ Calc. Among the selected herbicides, Propanil 360 g/1 EC showed the highest field use EIQ of 41.2 having the biggest impact. Ethoxysulfuron 15% WG had the lowest field use EIQ of 0.1 with the lowest impact. Ecological impact of MCPA 600g/1 SL, MCPA 400g/1 SL and Glyphosate 360g/1 SL was also higher in comparison to other herbicides. AZi171 sulfiron 50% WG, Bispyribac sodium 100g/1, Bispyribac sodium 20% WP, Penoxulam 240g/ 1SC, Cyhalofop-butyl 100g/1, Fenoxaproppethyl 75g/1 EW, Ethoxysulfuron 15% WG and Carfentrazone-ethyl 240g/ 1 EC have shown lower field use EIQ and therefore they were more environmental friendly herbicides.
Breeding performance of Pterophyllum scalare (Angelfish) fed with enriched Daphnia magna
(Uva Wellassa University of Sri Lanka, 2018) Mohamed Rashath, M.R.; Coswatte, A.C.W.W.M.C.L.K.; Withanage, P.M.; Liyanage, N.P.P.
Ornamental fish industry is a popular and profitable trade in the world. The production cost of ornamental fish varies with the cost of fish feed. The objective of the study was to investigate the breeding performance of Pterophyllum scalare fed with enriched Daphnia magna. The live feed of Daphnia magna was enriched with culture media, contained 58% crude protein and artificial feed with 40% crude protein were used to feed Pterophyllum scalare brooders (body weight l0g - 27g) as treatment I and II respectively. Square cement tanks with a size of 0.45 x 0.45 m2 were used for each treatment with 4 replicates for 80 days experimental period. Average Temperature, pH, Dissolved Oxygen, and Alkalinity in the two treatments were maintained at 28 °C, 7.4, 6.9 ppm and 560 mg 1-1 respectively. Although the brooders spawned in both treatments, the relative fecundity was not significantly different (P>0.05). Other breeding performances such as fertilization rate, spawn recovery and spawning period have shown significant differences (P<0.05) between Treatment-1 and Treatment-11. Comparatively highest fertilization rate (93.19%) and survival rate (70.87%) were observed in the Treatment-1, whereas lowest (fertilization rate: 67.31%) (survival rate: 50.55%) in Treatment-11. Most of the eggs in the Treatment-11 remained immature. Highest breeding performance was resulted with enriched Daphnia magna when compared to artificial feed in Pterophyllum scalare. The results revealed that the nutritional quality of the live feed considerably influenced on the breeding performance of Pterophyllum scalare.
Comparative Analysis of Morphological Characters of Blue Swimming Crab, Portuntis pelagicus (Linnaeus, 1758) Populations of Western and North-Western Regions in Sri Lank
(Uva Wellassa University of Sri Lanka, 2018) Disnika, A.V.H.R.; Senevirathna, J.D.M.; Liyanage, N.P.P.; Jayamanne, S.C.
The blue swimming crab, Portunus pelagicus, is abundant in indo-west pacific regions and extremely contributes for commercial fishery industry. In Sri Lanka, this species is typically found in Western, Northern, North-Western and NorthEastern Coasts. Morphological studies of P. pelagicus are important to identify population clusters and distribution patterns. Hence, this study was conducted to identify morphological variations of blue swimming crabs collected from Puttalum and Kalpitiya areas of the North-Western coastal region and the Negombo area of the Western coastal region. A Total of 240 individuals, 80 from each site were analyzed using twelve morphometric parameters. Standardized morphometric measurements were subjected to Discriminant Function Analysis (DFA) to observe intra-specific variations. According to the results, two discriminant functions were derived with 63.8% and 36.2% of variance for function I and 2 respectively, while function 1 was predicted as the strongest component (P < 0.05). The length to width ratio of the major cheliped merus (MEL/MEW=0.71) and ratio between carapace width (including 9th anterior-lateral tooth) to carapace length (CW2/CL-0.59) were identified as highly contributing parameters for function 1 and 2 respectively. The overlapped group plots suggested that there was no intra-specific morphological variability among three populations. Based on the results, it can be suggested that all three P. pelagicus groups are morphologically similar and consider as one population. The length-weight relationships of crabs in all three sites recorded negative allometric growth (b<3). However, results need to be confirmed using molecular data. Results of the current study provide basic information which could be utilized when constructing management plans on fisheries and conservation for this economically important carb species.
Comparison of Blue Swimming Crab, Portunus pelagicus (Linnaeus, 1758) populations from Batticaloa and Trincomalee areas in Sri Lanka using Morphometric Parameters
(Uva Wellassa University of Sri Lanka, 2018) Soyza, W.A.D.; Senevirathna, J.D.M.; Liyanage, N.P.P.; Jayamanne, S.C.
Western, Northern and Eastern areas of Sri Lanka are famous for blue swimming crab fishery. However, very limited studies have been carried out to identify their population structure. This study investigated the utility of morphological characters to differentiate Portunus pelagicus populations of two different areas in eastern province of Sri Lanka. Samples were collected from Batticaloa (n=46) and Trincomalee (n=46) waters throughout its known geographic range. Twelve morphometric characteristics were measured up to nearest 0.01 mm. Discriminant Function Analysis (DFA) was performed to analyze significant intra-specific variations of two populations using standardized morphometric characteristics. The derived single discriminant function was totally accounted for 100% variance (Wilks' Lambda=0.74, P<0.05). The carapace width to carapace length ratio (CW2/CL) was recorded the highest canonical discriminant function coefficient (0.89), thus CW2/CL was selected as the most suitable parameter for the predicted model. The two centroids derived by DFA were 0.59 and (-0.59) respectively for the Trincomalee and Batticaloa, and predict the separation of two groups. According to the plotted graph, minimal overlapping between two groups was observed with possible variation between two populations. Two different allometric coefficients (b) were recorded as 2.92 (closer to isometric growth) and 2.76 (negative allometric growth) for Trincomalee and Batticaloa populations respectively. Hence, the results suggest that there is a possibility of having two P. pelagicus stocks in the 2 sites of the eastern part of the island. Changes of prevailing environmental conditions and habitat are the factors that lead to morphological differences of two P. pelagicus populations. Finding of this study is important for implementations of site-specific sustainable fishery management programs. Further, population genetic studies are recommended to confirm the results of the present study.
Comparison of DNA Isolation and Dominant and Co-dominant Molecular Markers to Reveal the Genetic Sex of Gallus domesticus (Domestic Chickens)
(Uva Wellassa University of Sri Lanka, 2018) Nirmali, W.K.R.; Warnakula, L.; Cooray, R.; Hapuarachchi, N.S.; Magamage, M.
The whole blood of chickens contains nucleated erythrocytes and thrombocytes which yield high amount of DNA thus cause many troubles during DNA extractions. Optimization of DNA extraction from avian blood is important to yield high quality DNA and is vital for the success of all downstream applications. Determination of genetic sex of chickens is an important aspect in the avian research as well as in layer industry. Among the various methods of sex determination, Polymerase Chain Reaction (PCR) based methods are considered as most accurate and inexpensive. PCR methods have been developed based on the amplification of sex chromosome linked dominant and co-dominant loci in the chicken genome to distinguish between sexes. Success of this PCR based genetic sexing depends on the optimization of the PCR conditions and the reliability and reproducibility of molecular markers. Therefore this study was aimed at investigating the optimum conditions of DNA isolation from chicken blood and to compare the reproducibility of one co-dominant and two dominant sex markers to be validated as a tool for sex determination in avian research. Six different extraction procedures including manual and solution based commercial purification kit were evaluated. Efficacy of procedures was assessed with different combinations of initial blood, lysis buffer, and protein denaturant in related to the DNA yield and purity. Three primer sets namely CHD1, HUR 0423 and HUR 0424 were evaluated for the genetic sexing of chicken by polymerase chain reaction. The study results showed that an initial volume of 10 µL blood yields a significantly high DNA with high purity. Dominant marker HUR0424 showed to be a reliable marker system for the genetic sexing of domestic chickens over co-dominant markers.
Comparison of High Performing Seedlings and Vegetatively Propagated Tea Cultivars in Selected Tea Estates in Badulla.
(Uva Wellassa University of Sri Lanka, 2018) Bandara, M.M.N.T.; Alwis, L.M.H.R.
Prolonged drought is a major problem that prevails in Badulla. There are well adapted seedling teas in estates which also gives a higher yield like TRI recommended cultivars. This study was conducted for comparison of morphological characters of high performing seedling teas and extensively usedvegetatively propagated tea cultivars in selected tea estates of Badulla. Three estates were selected based on the climatic conditions and the recommendation by the Balangoda Plantations PLC. Fifteen morphological characters were considered for the cluster analysis such as number of pluckable shoots, shoot weight, banji shoots, internodal length, leaf angle and pose, leaf length, leaf width, young leaf pubescence, leaf waxiness, greenness, waviness of leaf lamina, leaf blade attitude, pigmentation of leaf petiole and stomatal density. Measurements were taken from five seedling teas as S 1, S2, 53, S4 and S5 and three recommended vegetatively propagated cultivars from each estate. Mean comparison was conducted for the characters which were significantly different. Selected teas were clustered separately without overlapping and showed each as a specific genotype. S2 seedling clustered with TRI 3015 and showed the highest mean value for considered characters in Uryestate. S3 seedling showed the highest mean values but none of the TRI recommended cultivars were clustered with S3 in Thelbedda estate. In Spring Valley mean values of S5 was the highest andclustered with CY9. Therefore S2 from Ury, S3 from Thelbedda and S5 from Spring Valley can be recommended as potential mother bushes to obtain cuttings for nurseries.
Comparison of Two different Commercially Available Vitamin-Mineral Premixes in Broiler Diets on Growth Performance and Meat Quality of Broiler Chicke
(Uva Wellassa University of Sri Lanka, 2018) Weerasinghe, W.M.S.S.; Gunawardana, K.G.U.I.P.; Priyadarshana, S.P.M.; Anand Kumar, S.; De Silva, P.G.J.C.; Nambapana, N.M.N.; Jayasena, D.K.D.D.
This study was conducted to determine the effectiveness of two different vitaminmineral premixes on performance, meat quality and meat composition of broiler chicken. A total of ninety (n. = 90) day-old male broiler chicks were randomly assigned into three dietary treatments. Each treatment comprised three replicates and ten broiler chicks were included in each replicate. Broilers were allocated to one of the three diets and fed for 42 days in a completely randomized design. The dietary treatments included two different premixes as T 1 (Basal diet + VitaminMineral premix 1) and T2 (Basal diet + Vitamin-Mineral premix 2) and the control group (To) fed with the basal diet only. The highest (p < 0.05) daily body weight gain (56 gbird-iday-I) and the lowest (p < 0.05) feed conversion ratio (1.68) of broiler birds were recorded from the birds fed T, diet. The highest (34%) and the lowest cook loss (33%) (P < 0.05) were recorded from T2 and T, treatments, respectively. The highest (p < 0.05) manganese concentration (0.065 mg/L) and the crude protein percentage (26%) of chicken breast meat were recorded from the birds fed Ti diet and the lowest manganese concentration (0.0213 mg/L) was recorded from the birds fed control diet. The highest (9%) and the lowest (4%) ash percentages (P < 0.05) were recorded from T2 and T1 treatments, respectively. The pH, color, water holding capacity and texture of broiler breast meat were not affected (p > 0.05) by dietary treatments. In conclusion, the supplemental dietary vitamin-mineral premix 1 has made beneficial effects on performance and meat composition of broiler chicken than the dietary vitamin-mineral premix 2.
Detection of Fungal Contaminations in Export Coir Consignments
(Uva Wellassa University of Sri Lanka, 2018) Weerapura, W.H.T.P.; Subhashini, M.H.A.D.; Chandrasena, G.; De Silva, P.D.P.M.
Coir or coconut fibre is a natural hard fibre extracted from the husk of the coconut. Coir is a good source for harboring and growth of fungi due to the high moisture content and the nutrients, it can support the growth of pathogens harmful to men, animals and plants. Export market is looking for coir products with minimum contaminants which is important to control the crop infections and maintain the human health. In the present study attempt was made to identify the fungal species present as contaminants in the export coir consignments which threatens the bio security of importing countries. Fungi in coir samples were isolated by inoculating the PDA plates with direct culture 'method and dilution series method under the aseptic conditions. Nine fungal species were isolated after 72 hours of incubation period. Isolated fungi were sub cultured separately to obtain the pure cultures which is important in the process of identification. Fungal and spore morphology was examined under the inverted compound microscope (Labomed TCM 400) for the identification of fungal species. Mucor sp., Aspergillus sp., Fusarium sp., Colletotrichum sp., Geotrichum sp., Paradoxa sp., Rhizopus sp., Trichoderma sp., and Penicillium sp., were found after the investigation of 8 samples of different coir exporting companies in Sri Lanka. Aspergillus sp. and Mucor sp. were the most abundant fungal species among the companies while Paradoxa sp., Fusarium sp. and Trichoderma sp. were recorded only in samples from 3 companies.
Determination of Differences in Heat Tolerance of Exotic Coconut (Cocos mrcifera L.) Cultivars by In vitro Pollen Germination
(Uva Wellassa University of Sri Lanka, 2018) Madushani, K.P.I.; Nainanayake, A.D.; Vidhana Arachchi, L.P.
Different germplasm accessions available at Coconut Research Institute of Sri Lanka have been used for developing new crosses with favorable characteristics such as high yielding potential and resistance to abiotic stresses. Some crosses which were developed using exotic pollens have been evaluated using some physiological traits yet some important flower characteristics have not been assessed. As nut is the main economically important component of coconut, it is essential to evaluate the reproductive performance of such new hybrids. Successful fruit set in coconut depends on several reproductive processes. These processes heavily depend on environmental conditions. Along with the phenomenon of global warming, it is imperative to identify the potential of new exotic hybrids which can withstand high temperatures. The pollen germination response was quantified in order to determine the differences in heat tolerance and to determine cardinal temperatures of four exotic coconut cultivars by in vitro pollen germination. Newly developed exotic hybrids namely TBGD, TRIT, TTMRD and TTAGT planted in the Middeniya Research Center were used. Pollens were collected from six palms from each hybrid. Pollen germination percentage was recorded after incubation for 20 hours in artificial growth media under different temperatures range from 22 °C to 40 °C. Quadratic model best described the response of pollen germination to temperature. All hybrids reached maximum pollen germination mostly in the range of 26 °C — 32 °C. The monthly mean cardinal temperatures over hybrids ranged from 18.52-23.09 °C, 22.08-32.73 °C, 36.91-56.42 °C for TBGD, 16.92-21.71 °C, 22.15-31.80 °C, 40.44-43.62 °C for TRIT, 8.89-21.53 °C, 28.71-31.84 °C, 40.3648.53 °C for TTAGT and 18.11-21.54 °C, 29.43-32.44 °C, 39.99-43.91°C for TTMRD. It is evident from the results that all exotic hybrids have a wider temperature adaptability than most of the commercially grown cultivars in Sri Lanka.
Determination of Geographical Variations of Heavy Metals in Swordfish (Xiphias gladius) and Yellowfin Tuna (Thunnus albacares)
(Uva Wellassa University of Sri Lanka, 2018) Digoarachchi, D.A.S.U.; Walpita, C.N.
Bioaccumulation of heavy metals in marine fish has emerged as a serious health concern in consumers and economic burden to fish exporters. Heavy metal concentrations of fish found in Sri Lankan fishery products may cause risks of border rejections and economic losses. However, data are yet to be available in this regard. Present study was conducted to explore geographical variation of heavy metal accumulation in the swordfish (Xiphias gladius) and Yellowfin tuna (Thunnus albacares). The heavy metal analysis data (Hg, Cd, As, Pb) were collected from two fish export companies in Sri Lanka. Cd, As, Pb metals were not detectable in samples. There were 302 mercury analysis data of swordfish during June to September, 2017 and 33 mercury analysis data of yellowfin tuna during January, 2015 to August, 2017. According to the collected secondary data, particular way points were traced using log sheets. Then using QGIS software, monthly heavy metal variations were mapped against fish species. Results showed that heavy metal analysis data concentrated in main 4 areas between 64°00'00.000"E70°00'00.000"E & 0°00'00.000"N-8°00'00.000"N,76°00'00.000"E-80°00'00.000"E & 0°00 '00. 000"N-8°00'00.000"N,88°00'00.000"E-92°00 '00.000"E & 14°00'00.000 "N18°00'00.000"N and 82°00'00.000"E-90°00'00.000"E & 6°00'00.000"N14°00'00.000"N.The results revealed that Mercury is the major heavy metal that accumulates in the Swordfish and Yellowfin tuna. According to EU standards, Mercury accumulation is higher in Swordfish that exceed 1ppm standard limit. Accumulation is highest in the fish harvested in the area of 64°00'00.000"E70°00'00.000"E & 0°00'00.000"N-8°00'00.000"N.Accumulating proportion to its harvest was 40.33% that exceeds 1ppm level. The next highest mercury levels were found in the 88°00'00.000"E-92°00'00.000"E&14°00'00.000"N-18°00'00.000"N and proportion to the total harvest was 10.81% which is greater than 1ppm.In conclusion, the fish caught from these two areas tend to have more Mercury contaminations than those of other areas, suggesting possible predictive modeling applications for heavy metal accumulations in fish.
Determination of Suitable Breeding Substrate for Redside Barb (Puntius bitnaculatus) in Captive Conditions
(Uva Wellassa University of Sri Lanka, 2018) Wajiramala, G.K.Y.; Mahaliyana, A.S.; Chandrarathna, W.P.R.; Jayamanne, S.C.
Redside barb (Puntius biniaculatus) is one of the most popular indigenous ornamental fish species, which commonly found in Sri Lanka. This species has been heavily collected from wild for aquarium trade and have a severe influence on the reduction of naturally available stocks. Development of captive breeding and larval rearing techniques are found as an effective strategy to increase commercially available stocks, which will also lead to ensure the sustainable utilization as a valuable resource. Hence, the objective of this study was to determine the suitable substrate for successful breeding of Redside barb in captivity. Three types of breeding conditions; gravels with aquatic plants, sand with aquatic plants, only aquatic plants were provided with stilled water in 60 cm x 30 cm x 30 cm size indoor glass tanks and three replicates for each treatment were used. Mature males with bright red colour stripe on their body and females which released yolked eggs, when slight pressure is applied on their abdominal region were selected as brooders for the experiment. Selected individuals were introduced into each tank at 2:1 male to female ratio. Completely Randomized Design was used as the experimental design and produced fry number was counted. Data were analyzed using one way ANOVA. Spawning was observed in all conditions and fry number varied significantly among three different substrates (p<0.05). The highest mean fry number was observed in the substrate of gravel with aquatic plants (195±20) compared to other 2 (fry number in the substrate which contain sand with aquatic plants: 77±39 and only aquatic plants: 33+33). Results of this study revealed that the most suitable breeding substrate for the Redside barb in indoor glass tanks was the substrate with a gravel bottom and aquatic plants.
Determination of the Appropriate ayza sativa (Rice) Straw Fertilizer Loading Level to Enhance Survival Rate of Catla calla (Catla) Post Larvae
(Uva Wellassa University of Sri Lanka, 2018) Maddumaarachchi, M.A.D.U.; Somarathna, K.M.D.M.; Liyanage, N.P.P.
Introduction of the Indian major carp species like Catla calla (Catla), Labeo rohita (Rohu) and Cirrhinus mrigala (Mirigal) has been resulted in a significant development in inland fisheries in Sri Lanka. Among these introduced fish species, Catla contributes to freshwater fish production in Sri Lanka significantly. One of the identified problems in Aquaculture Development Center, Udawalawa was lower survival rate of Catla post larvae at nursery stage. Hence this study was conducted to determine appropriate rice straw loading level to enhance survival rate of Catla post larvae reared in nursery tanks of 20 m2. The experiment was conducted using a Completely Randomized Design (CRD). A preliminary fertilizing procedure was done to determine a defenitive range (75-90 g m2 of dried rice straw) to conduct the experiment and the tanks were fertilized at above rates. Body weights and total lengths of post larvae were recorded at stocking and water quality parameters were recorded twice a day in each treatment. Number of survived post larvae in each treatment were recorded with the body weights and total lengths at the end of the rearing period. Recorded data were analyzed using one way ANOVA and Tukey test was used to compare mean values at 5% significance level. Total plankton count, survival rate, length gain and weight gain of post larvae were significantly different (p<0.05) among treatments. 80 g m-2 loading level of rice straw was the best treatment showing highest survival rate (66.6210.69), greatest length gain (159.0816.99 cm), maximum weight gain (2,5761176g) and highest mean value of total plankton count (54,9101646). Adequate amounts of planktons and proper water quality parameters act as major reasons for higher survival rate of Catla post larvae. Therefore, the loading rate of 80 g In-2 was found to be best among treatments for fertilizing Catla nursery tanks with rice straw to enhance survival rate.
Development of Fumigation Protocol for Liquid Phosphine for the Control of Rice Weevil (Sitophilusoryzue) in Stored Milled Rice
(Uva Wellassa University of Sri Lanka, 2018) Seelawansha, K.A.T.L.S.; Warshamana, I.K.; Nugaliyadde, L.; Weerawansha, A.N.R.; Herath, H.M.S.K.
An experiment was designed to develop a fumigation protocol for liquid phosphine (2% phosphine and 98% liquid carbon dioxide) to control rice weevil (Sitophiltisolyzae) in stored milled rice and thereby to increase the food safety at the quarantine service in Sri Lanka. The experiment was laid out in a Complete Randomized Design with eight concentration levels of liquid phosphine;10, 20, 35, 50, 100, 150, 200, and 250 g (equivalent to 140, 280, 490, 700, 1400, 2100,2800, and 3500 ppm, respectively) with a control treatment. All treatments were replicated three times. Each concentration level was tested under two time regimes (24 and 36 hrs.) and 50 same-aged adults were introduced to glass vials with 50 g of milled rice in each. Similarly, other life stages viz. pupae, larvae and egg infested rice, each weighing 50 g, were introduced separately to vials for fumigation. Mortality of S. oryzae was recorded soon after the fumigation as well as 1, 4, 7, 14, 21, 28 and 35 d after fumigation. In the eight treatments, except for the control treatment, 100% mortality was recorded inthe adult stage, in both time regimes. After 14 d of treatment, all tested concentration levels against pupae of S.oryzaesh ❑ wed mean newly emerged adult numbers of 0.67, 0.67 and 0.33 (P < 0.0001) at 140, 280 and 490 ppm, respectively, forthe 24 hrs.time regime and 0.33, 0.33 and 0.67 (P 0.053) at 140, 280 and 490 ppm, respectively,for the 36 hrs. time regime. After 28 d, 24 hrs.treatment of liquid phosphine concentrations against the eggs of S. oryzae recorded a mean newly emerged adult number of 0.67 (P = 0.003) at 280 ppm whereasthe 36 hrs.treatment of liquid phosphine yielded adult numbers of 0.33 and 0.33 (P = 0.322) at 140 and 280 ppm, respectively. The lowest concentration and the lowest fumigation time to achieve 100% mortality of all stages of S. oryzae was 700 ppm with24 hrs.of fumigation time. Therefore, the concentration level of 700 ppm with 24 hrs. of fumigation time can be declared suitable for achieving 100% mortality of S. oryzae, as per the present findings.
DNA Based Analysis for Distribution of Meloidogyne Species in Selected Crop Plants in Different Geographical Locations in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2018) Paramalingam, D.; Hettiarachchi, G.H.C.M.; Rajapakse, R.V.D.U.P.
Meloidogyne species are highly destructive endoparasitic nematodes with a wide host range. Molecular identification of the Meloidogyne species that infect crop plants was performed in this study using Meloidogyne infected 28 root samples collected from four different crops in five different geographical locations in Sri Lanka during May to July in 2017; Passara (6.934909, 81.152698) tomato, Thanamalwila (6.439755, 81.133397) chili, Pallekele (7.280104, 80.702034) capsicum, Vellankulam (9.186089, 80.126481) chili, Kaluwanchikudy (7.529373, 81.794609) chili and Kaluwanchikudy (7.529373, 81.794609) okra. Polymerase chain reactions were carried out in these samples with MF/MR primer pairs, C2F3/1108 primer pairs and 194/195 primer pairs. Genus specific universal primers MF/MR amplified, 500 by fragment of ribosomal DNA of Passara tomato, Thanamalwila chili, Pallekele capsicum, Vellankulam chili and Kaluwanchikudy chili samples representing the presence of genus Meloidogyne. Primer pair C2F3/1108 amplified, 705 by fragment of mitochondrial DNA of Thanamalwila chili, Pallekele capsicum, Vellankulam chili and Kaluwanchikudy chili samples representing the presence of Meloidogyne enterolobii. Primer pair 194/195 amplified, 700 by fragment of ribosomal DNA of Passara tomato and Kaluwanchikudy chili samples representing the presence of Meloidogyne hapla. A mixed population of M. enterolobii and M. hapla was resulted in Kaluwanchikudy chili. Kaluwanchikudy okra did not produce any band with any primer pair amplifications revealing that it had unknown species. This study confirms the expansion of the distribution of M enterolobii and M. hapla in Sri Lanka in recent years. M. enterolobii was present in all the chili/capsicum samples tested and this is the first report of its availability in infested chili/capsicum plants in Sri Lanka.
Effect of Coloured Cellophane Shading on Seed Germination, Plant Growth and Fruit Quality Characteristics of Tomato (Solanunt lycopersicum L.)
(Uva Wellassa University of Sri Lanka, 2018) Sugathapala, D.H.D,M,; Dissanayake, P.K.; Wekumbura, W.G.C.
In urban agriculture there are trends to grow crops tinder different colour shading. Colour of light differently affect on plant growth and biochemical properties of plant. The present study was conducted to evaluate the effect of coloured shading on seed germination, plant growth, fruit quality and fruit yield of tomato (Solarium lycopersicum L). Yellow, red, green, blue coloured cellophane and transparent cellophane (control) were used in the experiment. To evaluate quality of fruits two experiments were conducted in a polythene house with Complete Randomized Design; (1) whole fruit covered by coloured cellophane and (2) whole plant covered by coloured cellophane. The coloured cellophane shading differently affected on seed germination, growth, fruit quality and yield of tomato. The highest seed germination was observed in yellow colour (93.47%) and the lowest at green (73.25%) at day 6th of germination. At one month after transplanting highest and lowest plant height (24.5 cm, 13.5 cm) and number of leaves (8, 7) were found in yellow and green, respectively. The highest leaf area (20.07 cm2) and plant fresh weight (4.83 g) were found in control; whereas, the lowest was found in green (4.34 cm2, 0.74 g, respectively). The highest fruit weight (35.13 g) and length (3.97 cm) were found in the fruits covered by green cellophane; whereas, the lowest (24.74 g, 3.20 cm) in the blue (Experiment 01). The highest Brix value was found in red and the lowest from yellow. Ascorbic acid content was highest in yellow colour (90 ing/100m1) but lowest in green colour (30 mg/100m1). In the experiment 2, blue cellophane recorded the highest fruit weight (51.10 g), and size; whereas, the control recorded the lowest. Brix value was higher in control and the lowest in blue colour. Fruit peel thickness was higher in red (0.65 cm) and lowest in blue (0.51 cm). The highest Ascorbic acid content was recorded in yellow colour (121.25 mg), whereas the lowest in blue (57.5 mg). Finally, it can be concluded that yellow colour is the most effective on accelerating seed germination and control treatment is better for vegetative growth of the plant. To have high ascorbic acid content whole plant should be covered with yellow cellophane, but when it consider yield, blue cellophane is the best.
Effect of Deep Litter and Slatted Floor Systems on Broiler Breeder Performance of, Hatchability, Fertility and Exterior Quality of Eggs
(Uva Wellassa University of Sri Lanka, 2018) Kasthuriarachchi, K.A.D.H.; Gamlath, G.A.S.N.; Nambapana, N.M.N.
An experiment was conducted to compare the effect of deep litter and slatted floor systems on broiler breeder performance, hatchability, fertilityand exterior quality of eggs. A total of 23100 female and 2100 male commercial broiler breeders (Cobb 500) were randomly assigned in to two different treatments and housed under two different rearing systems (deep litter and slatted floor) from 26 to 34 weeks of age. Each treatment replicated three times. Data were recorded daily and analyzed using Analysis of Variance (ANOVA) in Complete Randomized Block Design (RCBD) and means were separated using Tukey's means of comparison. The highest (P < 0.05) female body weight (3.6 kg), number of damaged eggs (143) and number of destroyed eggs (99) were recorded from 2/3rd of slatted floor system. The highest (P < 0.05) daily egg production (2846), male body weight (4.1 kg), and number of floor eggs (40), number of doubled yolk eggs (270), number of misshaped eggs (12) were recorded from deep litter system. Female and male mortality percentage, egg weight, number of tiny eggs, fertility and hatchability percentages were not affected by floor systems (P > 0.05).The results concluded that birds reared on deep litter system were exhibited better broiler breeder performance as compared to slatted floor system during 26 to 34 weeks.

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