UWU Repository :: Browsing by Author "Silva, P.D.P.M.D."

Browsing by Author "Silva, P.D.P.M.D."

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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.
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.
Detection and Confirmation of Phytoplasma Disease in Different Crop Species by Using Molecular Technology
(Uva Wellassa University of Sri Lanka, 2016) Amarasinghe, A.A.I.M.; Alwis, L.M.H.R.; Silva, P.D.P.M.D.; Basnayake, B.M.V.S.; Tennakoon, T.M.N.D.; Nandasena, K.D.
Phytoplasma disease is caused by plant pathogenic Phytoplasmas, which are cell wall less bacteria that causes devastating losses in yield and quality of crop production in Sri Lanka. Effective control is required to minimize the spread ofthe disease through identification of the organism. Detection and confirmation of phytoplasma diseases in infected crop species by using molecular technology required to gain rapid accurate results in identification to compete with increment of virulence ofthe pathogens. However, there are least number of research conducted on phytoplasma diseases in Sri Lankan context. Hence, this study was conducted as a molecular approach for phytoplasma detection, identification and confirmation. The Polymerase Chain Reaction based method was used with universal primers for 16S rRNA gene to detect phytoplasma in fifty different suspected crop species and the amplified DNA fragments in 557 by were visualized on 2 % agarose gel. Thirty-six crop species gave positive results with producing DNA fragment in 557 by size. For accurate detection of phytoplasma caused symptoms in Sapota (Manilkara zapota) and Petunia (Petunia sp.) two oligonucleotide primers were designed, using sequenced phytoplasma DNA extracted from infected Sapota and Petunia plants. Those designed primers were characterized, optimized and primer specificity was analysed. Primers Mx for Sapota is forward -5'- GCCAGGCAGTCCACTTATCA-3' and reverse 5'- GTGCACGCCCTAAACGAATC-3'. The length of the primer was 20 bases and detectable band in gel profile was 88 bp. with three unstable hairpin loops. Primer Mx best annealing temperature was 50 and showed 90 % specificity. Primers Px for petunia is forward sequence '5-CGGCTTGGCTACCCTTTGTA-3' and reverse sequence 5' - TACCTGGCCTTGACATGCT-3. The length of the primer was 20 bases and detectable band in gel profile was 288 bp. with eight unstable hairpin loops. Primer Mx best annealing temperature was 45 and showed 30 % specificity. Mx and Px primers can be used for specific, sensitive detection of phytoplasma infect to Sapota (Manilkara zapota) and Petunia (Petunia sp.) plant species. Key words: Phytoplasma, Polymerase chain reaction, Primers, Gene sequencing, Template DNA
Development of Polyphenol Incorporated Herbal Hair Shampoo by Using Tea Fluff
(Uva Wellassa University of Sri Lanka, 2016) Peduruarachchi, D.M.N.H.; Silva, P.D.P.M.D.; Gunadasa, H.K.S.G.; Samaranayake, H.G.H.
Usage of cost effective herbal cosmetic products have become a new trend among the people. Tea polyphenol is one of the food derived active ingredients which has potential of hair growth. Since tea fluff is a cost effective polyphenol rich wastage, can be used to produce several natural cosmetic products with lower side effects and higher safeness. Therefore the major objective of this study was, development of polyphenol incorporated herbal hair shampoo by using tea fluff as a value added product which is effective towards hair growth and safeness. This study was used to determine the best polyphenol incorporation level to the shampoo based on its sensory properties, show the potential of used tea fluff as a cost effective polyphenol rich source for new product development, show the potential of value addition to the wastages and effectively utilize the wastages for the purpose of cost effective waste management method. Polyphenol extract of tea fluff was appended into shampoo base with varied concentrations i.e. 2.1%, 2.3%, 2.5%, 2.7% and 2.9%. Further sieved tea fluff was appended into shampoo base with varied proportions i.e. 0.021%, 0.023%, 0.025%, 0.027% and 0.029%. A sensory evaluation test was carried out with 30 panelists to reveal the best treatment. A shelf life analysis was performed at the storage of room temperature for the selected best treatments for period of two months at two weeks of interval. Results revealed that hair shampoo was stable in room temperature. According to the results of the sensory evaluation and statistical analysis, it can be concluded that 2.1% of polyphenol extract with 97.9% shampoo base (most preferable formula) and 0.025% of tea fluff with 99.975% shampoo (contains the highest polyphenol level) base are the two best formula among the two series. Keywords: Tea fluff, Polyphenol, Shampoo, Hair growth, Sensory evaluation
Effect of Gamma Irradiation on Microbiological and Physicochemical Properties of Dehydrated Carrot (Daucus carota L.) and Dehydrated Ripe Jackfruit (Waraka) (Artocarpus heterophyllus L.)
(Uva Wellassa University of Sri Lanka, 2020) Madushani, R.V.C.; Wijesinghe, W.A.J.P.; Ranasinghe, R.D.R.; Silva, P.D.P.M.D.
Dehydrated ripe Jackfruit (waraka) and carrot have a high demand in the local and export market due to their health benefits and the use as ingredients for the food industry. The study was carried out to evaluate the effect of different gamma irradiation doses on physicochemical parameters and microbial quality of dehydrated waraka and carrot in Sri Lanka. Dehydrated waraka and carrot samples were collected and irradiated at doses of 0 kGy, 2 kGy, 4 kGy, 6 kGy, 8 kGy, and 10 kGy by industrial Co-60 gamma irradiator at dose rate 5.3 of Gy min-1 . Under physical parameters, water activity and moisture content were measured for each of the treatments. Total plate count, yeast, and mold count and coliform counts were determined by using ISO modified method. Antioxidant content by following DPPH free radical scavenging method, total phenolic content by following Folin- Ciocalteu (FC) method, and beta carotene content by using AOAC 1980 method was analyzed in all the irradiated samples and non-irradiated samples and all physicochemical and microbial treatments were replicated in three times. The average moisture content of irradiated waraka and carrot samples was 97.04±0.09% and 96.37±0.09% respectively. The average water activity of irradiated waraka and carrot samples was 0.49±0.00 and 0.50±0.00 respectively. Antioxidant activity and total phenolic content of the waraka and carrot samples showed no significant difference (P˃0.05) among different-irradiation doses. However, the content of beta carotene has been reduced (P˂0.05) with the increase of irradiation-dose. Both irradiated waraka samples and carrot samples showed a reduction (P˂0.05) of total plate count with the increase of irradiation dose. There was no growth of yeast and mold and Escherichia coli in all the gamma-irradiated samples. It was concluded that the most preferable irradiation doses for preserving the physical and nutritional quality and microbial safety of dehydrated waraka and dehydrated carrot were 2 kGy and 4 kGy. Keywords: Dehydration, Waraka, Carrot, Gamma irradiation, Dose
Effect of Melting on Flavor Granules Used in Flavored Tea Bags
(Uva Wellassa University of Sri Lanka, 2016) Chandrasir, A.B.K.; Bandara, S.M I.P.G.; Silva, P.D.P.M.D.; Wanasinghe, K.D.K.
Flavored tea highly contributes to the value added exports and causes high revenue to the county. Sri Lankan value added tea in total tea exports increased slightly from 39%to 42% in 2014.Although flavors play a big role in the value addition process, hygroscopic property of black tea, hot and humid environment may cause a deleterious effect for the final products. The main quality problem found in flavored tea is melting of flavor granules during the storage and transportation, leading to quality failure and the final product, therefore, is not in compliance with the expected standard. This research was focused to determine the effect of temperature, relative humidity and the storage time of the product on melting of three types of flavor granules such as strawberry, forest fruit and honey. The melting effect on flavor granules was assessed under three levels of temperature (28 ± 2 °C, 33 ± 2 °C, 38 ± 2 °C) and three levels of relative humidity (58 ± 2% , 68 ± 2% , 78 ± 2%), altogether as nine treatments. The physical state of flavor granules was observed during the six weeks for three months. Binary logistic regression is used to identify the relationship between the predictors and the prediction. Results revealed that temperature, relative humidity affected significantly on melting of flavor granules. Storage time also had a significant effect on melting of strawberry flavor granules and honey flavor granules. Flavor melting indicated a significant increase with the increase of temperature and relative humidity. Keeping relative humidity at 58±2 % and temperature at 28+2°C is the best level in order to mitigate the amount ofmelting of flavor granules used in black tea. Keywords: Black tea, Flavor granule, Liquid flavor, Relative humidity, Temperature
Estimation of Quality of Black Tea Grades by Different Brewing Methods and Their Chemical Composition
(Uva Wellassa University of Sri Lanka, 2016) Shivanth, S.; Allakolanga, A.G.A.W.; Silva, P.D.P.M.D.; Cooke, A.A.
The objective of the present study was to determine the optimal brewing methods and their contribution to the in-cup chemical composition as well as to correlate the chemical composition of tea infusions to their sensorial properties. BOP, PF1, FBOPF grades are obtained by different manufacturing methods. The fixed brewing temperature and time in preparation of tea for all grades were not effective for the extraction of full liquor characters to the brew. Black tea samples were brewed at different temperature levels (75 °C, 85 °C, and 95 °C) for 2, 5, 7, and 9 min using three different high grown black tea grades. Highly trained seven panellists evaluated different tea grades using a seven —point hedonic scale. The data were analyzed through the Kruscal-Wallis non parametric ANOVA method. Conover-Inman method was used for the selection of the best treatment combinations. Two factor factorial design was used for chemical analysis in each type and to determine the polyphenol content, correlation between tea quality attributes and in-cup chemical composition. Across all three black tea samples at 12 different brewing temperatures and time combinations, 95 °C for 9 minis the best temperature and time combination for brewing all the black tea grades. Also the extraction of polyphenol was increased by prolonging the infusion time for 5, 7, and 9 minutes. Keywords: Black Tea, Quality attributes, Brewing methods, In-cup chemical composition
Evaluating the Effect of Selected Synthetic Chemicals on the Growth of Pseudomonas spp. in Nitrile Latex
(Uva Wellassa University of Sri Lanka, 2018) Senarathne, M.D.T.K.; Kumara, E.A.S.; Chandrasena, G.; Silva, P.D.P.M.D.
Glove industry isconsiderable among the industries operating in Sri Lanka because of its significant contribution to the national economy. The presence of microorganisms in latex makes a severe impact on the properties of final product and, on human health. Specially, the Pseudomonas spp. pathogenic on human reported to produce a problematic bacterial slime layer on latex dipping tanks, in nitrile latex based disposable glove industry. This study was conducted to select a suitable synthetic antimicrobial chemical compounds to produce good quality glove products at low cost and withless impacts on human health. Pseudomonas spp. bacteria were isolated on selective culture medium, and identity of the bacterium wasconfirmedusing gram staining, methyl red reduction, H2S and the catalase tests. The effectiveness of changing process parameters such as pH level and temperature according to company standards and selected synthetic antimicrobial compounds namely; acticide biocide and proxel gel biocide were evaluated. The effect of changing process parameters and selected synthetic chemical compounds on tensile properties of the nitrile latex gloves were statistically tested,using one-way ANOVA. Accordingly, a significant reduction of bacterial growth on nitrile latex with decreased tensile properties on gloves was found after adjusting pH level of latex dipping tank into 10.5 using KOH and NH3. Further, the treatment with biocides wasidentified as the best bacterial control method and it was found that the acticide biocide was better than proxel gel biocide. Treatment with acticide biocide in the medium did not result in a significantdamage on the tensile properties of nitrile latex gloves. Therefore, acticide biocide can be applied for minimizing the growth of Pseudomona sspp. in nitrile latex glove production at low cost and with high bio security.
Formulation of Specific Culture Media for In-vitro Cultivation of Exobasidium vexans Massee
(Uva Wellassa University of Sri Lanka, 2019) Dhananji, R.A.D.W.; Kliyadasa, P.E.; Silva, P.D.P.M.D.
Blister blight is the most important and destructive foliar disease of tea that caused by an obligate parasite Exobasidium vexans Massee. Further investigation of this fungus in in-vitro condition has been restricted due to non-availability of effective culture media. This study has been conducted to find an effective culture media for the pathogen. Disease infected leaf samples for inoculation and blister blight susceptible healthy tea leaves for media preparation were collected around Uva Wellassa University of Sri Lanka, Badulla. The tested media were prepared by referencing standard PDA media using dextrose and agar with 50 g of dried fresh tea leaves powder, 250 mL of hot water tea extraction, 0.7% instant green tea and 0.7% instant black tea instead of potato as four treatments in four replicates using PDA as negative control and 0.7% calcium carbonate amended PDA as positive control. Each medium was inoculated with 30 spores mL-1 pure spore concentration of the pathogen and incubated under 28°C for observations. Colony diameter and number of days to show visible growth and respective colony morphologies on each media were measured. The Koch’s postulate was done by whole plant inoculation method for verification of the pathogen. The average growth area on the media with fresh tea leaf powder, hot water extraction, instant green tea, instant black tea were recorded as 60.82 cm², 36.32 cm², 9.62 cm², 8.55 cm² respectively. The number of days to show visible growth was same for all media. The culture media with particle size 0.5 mm dried fresh tea leaf powder that prepared using blister blight susceptible cultivar TRI 2025 was recorded the highest growth. The minimum growth was recorded in the media with instant black tea. Standard PDA media with particle size 0.5 mm dried fresh tea leaf powder that prepared using blister blight susceptible cultivar TRI 2025 is the best formulation for in-vitro cultivation of Exobasidium vexans Massee.
Investigating the Association of Vesicular Arbuscular Mycorrhiza (VAM) with Commelina benghalensis Weed Species in Tea Lands
(Uva Wellassa University of Sri Lanka, 2020) Wijesingha, W.A.H.M.; Prematilake, K.G.; Silva, P.D.P.M.D.
A study was conducted to investigate the association of Vesicular Arbuscular Mycorrhiza (VAM) with Commelina benghalensis (Girapala), which is an aggressive weed infesting in tea cultivations. A field experiment was carried out at Wewessa estate, Badulla from September to December 2019. Four treatments i.e. Tea infested with C. benghalensis slashed at 3 weeks interval, Tea infested with C. benghalensis slashed at 6 weeks interval and Tea with no weeding for 3 months and tea alone (weed-free), were included. VAM spore count and root colonization percentages were calculated at 6-week intervals. Soil Phosphorus was analyzed and tea yield was measured. VAM spore count and root colonization percentage were significantly (p<0.05) higher in two treatments with C. benghalensis compared to those of no weeding treatment. Spore counts were recorded as 190, 200 spores/100g of soil in the treatments of which C. benghalensis was slashed at 3 and 6 weeks interval, against 120 in no weeding treatment. Root colonization was also reported as 56.7%, 60%, 39.4% in tea infested with C. benghalensis slashed at 3 and 6 weeks interval, and no weeding treatments, respectively. Significantly higher levels of soil Phosphorus (241 ppm and 237 ppm) were also reported from two treatments of C. benghalensis slashed at 6 and 3 weeks intervals compared to no weeding (230 ppm) treatment at the end of 3 months. There was no significant difference in tea yield between treatments. The study concluded that there is an association of VAM with C. benghalensis and P solubilization is taken place with VAM colonization in the rhizosphere of C. benghalensis. VAM association with C. benghalensis weed has thus been favorably affected on tea growth. Keywords: Aeroponics, Growth, Yield, Potato mini-tubers, Quality, Root pruning
Investigation of Possible Vesicular Arbuscular Mycorrhizal (VAM) Associations in Prevalent Weeds in Tea Cultivations of Uva Region
(Uva Wellassa University of Sri Lanka, 2019) Ranasinghe, D.H.Y.A.; Prematilake, K.G.; Silva, P.D.P.M.D.; Gunasena, H.M.P.M.
A study was carried out to investigate the possible Vesicular Arbuscular Mycorrhizal (VAM) associations in some prevalent weeds. VAM association in roots of some weeds is said to be favourable for crop growth. Weed root samples from the rhizosphere of Ageratum conyzoides, Axonopus compressus, Bidens pilosa, Borreria latifolia, Cleome rutidosperma, Drymaria cordata, Eleusine indica, Erigeron sumatrensis and Oxalis corniculata were collected from two tea estates, Wewessa and Spring Valley in Uva region covering IM1a agro-ecological zone. Soil samples from the rhizosphere of each weed were collected and tested for soil pH. VAM root colonization percentages and spore counts were calculated using Grid method and Doncaster’s counting disc method, respectively. The highest VAM count was recorded as 47.67% with Axonopus compressus weed and the lowest as 20% with Eleusine indica. The highest spore number was counted as 265 with Borreria latifolia and the lowest as 70 with Axonopus compressus. The mean pH was within the range of 6.2 to 4.8 at 19 ± 1 °C in two locations.
Optimization of Fermentation Medium for Bioethanol Production from Palmyrah Molasses
(Uva Wellassa University of Sri Lanka, 2019-02) Sinnarasa, S.; Silva, P.D.P.M.D.; Alakolanga, A.G.A.W.; Mahilrajan, S.
Molasses is the waste material obtained from the production of palmyrah sugar candy and it could be used for alcohol production through fermentation process thereby it reduces the production cost of sugar candy. The aims of the study were to select the best yeast species and optimize the fermentation conditions to produce ethanol. The best yeast strain for fermentation was selected according to their alcohol tolerance and growth on molasses using the cell density count in spectrophotometer. Molasses was tested for the chemical parameters such as brix, total sugar, reducing sugar, pH, total acidity and alcohol before using it as fermentation medium. Optimization of fermentation was carried out with different initial brix (5, 10, 20, 30, 40 °Brix), inoculum size (1, 2, 3, 4 ml), pH (4, 4.5, 5, 5.5, 6, 6.5) and temperature (30, 35, 45, 55 °C). Each treatment was triplicated under controlled environment conditions. Results indicated that the absorbance 0.508 and 0.788 were obtained as highest cell density for high alcohol (8.5%) tolerance and growth on molasses, respectively. The best yeast strain was used for further fermentation studies and recorded the initial brix, pH, total sugar and reducing sugar values as 58.73 oBrix 4.5, 62.39 and 8.06%, respectively while the alcohol content given nil. Brix 10o and inoculum size of 3 ml were selected as the optimum at 3rd and 6th day of fermentation with mean value of 2.6 and 4.4 alcohol percentages among the different treatments. Optimum pH for the process was recorded as 4.5 and it gave the highest 4.6 alcohol percentage on 5th day while optimum temperature was 35 °C and resulted 4.8 alcohol percentages on 4th day. There was a significant decrease in total solids of all the treatments during the fermentation process. Bioethanol production from palmyrah molasses could be enhanced up to 72% by the optimization of fermentation condition (Brix, Inoculum size, pH, Temperature) using the selected yeast strain.
Screening a Bean Germplasm for Fusarium Wilt Disease, Caused by Fusarium oxysporum f. sp. phaseoli
(Uva Wellassa University of Sri Lanka, 2016) Perera, G.Y.A.D.D.; Chandrasena, G.; Silva, P.D.P.M.D.; Somachandra, K.P.
Fusarium wilt or Fusarium yellows is an economically important fungal disease of common bean worldwide. The causal agent of this disease is Fusarium oxysporum f. sp. phaseoli. The study was conducted to find the suitable medium for the multiplication and to determine the reaction of 30 common bean accessions, including two susceptible controls (Wade and Keppetipola Nil) to the Fusarium oxysporum isolates under greenhouse condition. Isolates of the pathogen were collected from the root and stem fragments of common bean plants grown in the production fields of Regional Agricultural Research and Development Center, Bandarawela. Species identity was based on the colony characters, nature of conidiogenous cell, and morphology of microconidia, macroconidia and chlamydospores. It was found that isolates had a relatively high growth in Bean extract Agar (BEA) medium, comparatively to Potato Dextrose Agar (PDA) and Corn Meal Agar (CMA) medium. Screening of the bean germplasm in the greenhouse was done by transplanting inoculated seven day old seedlings into pots filled with pasteurized (1:1) soil: sand medium. At 15 days after inoculation, the primary leaves showed epinasty symptoms and chlorotic areas appeared on leaves followed by necrosis at their margins of most accessions, including two recommended varieties. Disease severity was recorded 21 days after inoculation using a Disease Severity Index and it was observed that disease reactions in the germplasm varied from highly resistant to highly susceptible. Out of the 30 bean accessions including two recommended varieties there were 2 resistant, 19 intermediate and 11 susceptible accessions in the germplasm. Keywords: Common beans, Germplasm, Fusarium oxysporum f. sp. phaseoli, Fusarium wilt, Greenhouse screening
Screening of Bean (Phaseolus vulgaris) Breeding Lines against Fusarium Wilt Caused by Fusarium oxysporum f. sp. Phaseoli
(Uva Wellassa University of Sri Lanka, 2019) Inshirah, A.A.F.; Somachandra, K.P.; Jayasekara, E.A.E.S.S.; Alwis, L.M.H.R.; Silva, P.D.P.M.D.
Fusarium oxysporum f. sp. Phaseoli (Fop) is an important pathogen that causes Fusarium wilt in common bean (Phaseolus vulgaris L.). This disease is one of the most harmful diseases of bean worldwide. Use of resistant cultivars is the most reliable method of fusarium wilt prevention. There are no resistant varieties found in Sri Lanka so far. Identification of resistant breeding lines will help breeders to develop resistant or moderately resistant bean varieties. The objective of this study is to identify resistant/moderately resistant bean breeding lines against Fusarium oxysporum f. sp. Phaseoli among 19 common bean breeding lines developed at RARDC Bandarawela, Sri Lanka. These lines were evaluated with 2 susceptible controls (Wade and Keppetipola Nil) under greenhouse condition .Screening of bean breeding lines was done by transplanting inoculated seven day old seedlings filled with pasteurized sand: soil medium (4:1) into in disposable plastic cups. After 10 days of inoculation the disease symptoms such as chlorosis, necrosis and wilting of leaves were started appearing including 2 susceptible controls. Observations were taken after 21 days of inoculation and Disease Severity Index (DSI) was used to calculate on a resistant to susceptible. Out of 19 bean breeding lines including two control varieties it was identified 9 resistant (DSI 1-3), 10 intermediate (DSI 3.1 -6.0) , 2 susceptible (DSI 6.1-9.0) breeding lines. These bean breeding lines can be classified into three groups as resistant, intermediate and susceptible.

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