UWU Repository :: Browsing by Author "Jayasinghe, H.A.S.L."

Browsing by Author "Jayasinghe, H.A.S.L."

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Assessment of Sensory Acceptability of Diyamiththa (Cissampelos pareira) Leaves Extract Incorporated Lacto-vegetarian Set Yoghurt during Storage
(Uva Wellassa University of Sri Lanka, 2018) Madushanka, R.M.T.; Ranasinghe, M.K.; Jayasinghe, H.A.S.L.; Thilakarathne, W.M.M.H.; Priyadarshani, B.M.P.
The addition of stabilizers in dairy industry helps to improve viscosity and texture especially in set yoghurt production. The texture of yoghurt results from a complex interaction between milk proteins, acid and exopolysaccharide produced by starter culture. Gelatin is an animal originated stabilizer used in yoghurt production. Food habits in the world have started to change with an increasing demand for vegetarian food. Diyamiththa (Cissampelos pareira), a medicinal plant exhibit a unique gelling properties which could be an alternate for gelatin. Thus, the present study was conducted to assess the organoleptic acceptability of lacto-vegetarian set yoghurt with incorporation of a gel from diyamiththa leaves. Three levels of diyamiththa leaves extract (DLE) were used as treatments, 1%, 2% and 3% while 0.68% gelatin incorporated yoghurt served as the control. Treatments were evaluated by 30 untrained panelists for color, aroma, texture, mouthfeel, taste and overall acceptability (OA) attributes at 7 days interval for 21 days of storage at 4 °C. Data from sensory evaluation were analyzed using Friedman non-parametric test using Minitab 17®. Based on sensory evaluation at day 0 all treatments showed significant difference (P<0.05) with respect to all the attributes while 2% DLE incorporated yoghurt showed the highest estimated median values for both taste and 0A;7.50 and 7.78, respectively. Moreover, at day 21 treatments showed significant difference (P<0.05) with all attributes while amongst all treatments, 2% DLE incorporated yoghurt scored the highest estimated median values for texture, mouthfeel, taste and OA; 7.50, 7.06, 7.81 and 8.03, respectively. However, after 21 days of storage the organoleptic acceptability was declined particularly with taste and mouthfeel in all treatments. Results revealed that, 2% DLE incorporated set yoghurt can be stored for 21 days at 4 °C without deteriorating organoleptic properties.
Determinants for Contribution of Pineapple Growers for Export Volume in Gampaha District
(Uva Wellassa University of Sri Lanka, 2016) Rupasinghe, R.A.D.S.; Jayasinghe, H.A.S.L.; Rathnayake, R.M.P.S.; Silva, T.A.P.
Pineapple is the third largest agricultural product after tea and coconut which has a demand in export market. Although the nature has blessed with an ideal climate for growing wide range of delicious fruits including pineapple, Sri Lanka is not in a position to meet the growing demand. Therefore, that is very important to study about the export performance of fresh pineapple in Sri Lankan context. The general objective of this study was to identify the determinants of contribution of pineapple growers for export volume in Gampaha district. A structured questionnaire based survey was carried out to collect the data from random sample of 130 pineapple growers in Dompe and Diulapitiya DS divisions in Gampaha district. Tobit model was used to find out the relationship between dependent variable and other explanatory variables, and descriptive analysis was used to explain the characteristics of the sample. The result of Tobit model revealed that the contribution of pineapple growers for exports of pineapple was significantly determined by the age of grower, experience of the grower, pineapple cultivated land extent, amount supply for local market, domestic price and export price. The specific objectives of this study were to study the past export performance of fresh pineapple since 1990 to 2012 in Sri Lanka and to develop the forecasting model and the generalized model for fresh pineapple exports in Sri Lanka. There was an upward trend from 1990 to 2004 and trend was declined from 2004 to 2012 with some fluctuations. The reason was that the export of preserved pineapple has shown a significant improvement within last few years. The other specific objective was to develop the forecast model for future forecast and generalized model for current situation analysis for fresh pineapple exports in Sri Lanka. VectorAutoregressive Model was used to develop the forecast model and the generalized model was developed without considering the time factor. The result revealed that the export of fresh pineapple was significantly determined by the average exchange rate and the domestic price. Keywords: Export performance, Fresh pineapple, Gampaha district, Tobit model, Vector Autoregressive Model
Determination of the Variation of Biochemical Profile of Commonly Grown Tea (Camellia sinensis (L.) O. Kuntze) Cultivar of TRI 2025 in Low Country Agro-ecological Zones
(Uva Wellassa University of Sri Lanka, 2019) Nirmala, M.H.G.S.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.; Jeewanthi, P.W.
There is a unique taste, color and aroma of low country teas compared to other types of tea grown in Sri Lanka. Those properties are governed by the biochemical composition of the tea, basically the tea leaves. However, there was no reported study related to the variation of chemical profile of tea grown in different agro-climatic regions within the low country region. Therefore, this study was conducted to determine the variation of biochemical profile of commonly grown tea (Camellia sinensis (L.) O. Kuntze) cultivar of TRI 2025. Fresh tea leaves of TRI 2025 in 5th pruning cycle were randomly collected from eight selected plantations which represent four major tea cultivating agro-climatic regions WL1a, WL1b, WL2a, WL2b in low country. The estates were selected using stratified sampling technique and samples from each stratum were selected randomly from different tea estates in a way of including two estates in each agro-climatic region. The study was conducted during the period of onset of rain, from November to December, 2018. The fresh tea leaves placed on ice immediately after harvesting and transported. The leave samples were dried at 50 °C for 12 hours and crushed into fine particles. Chemicals were extracted from each sample using 1g of leaf powder in methanol for the analysis of polyphenols and reducing sugars while phosphate buffer was used for proteins extraction. Folin Ciocalteu regent method Lawry’s method and DNS reagent method was used to determine polyphenols, free sugars and total proteins with slight modifications, respectively. This study found that significantly different polyphenol and free sugar contents (p<0.05) were in teas grown in the four agro-ecological regions in low country of Sri Lanka but free total protein contents were not shown the significant difference.
Determination of the Variation of Biochemical Properties of Selected Tea Cultivar (Camellia sinensis (L.) O. Kuntze) in Mid Country
(Uva Wellassa University of Sri Lanka, 2019) Samarakoon, S.M.I.S.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.; Jeewanthi, P.W.
In the tea trade, quality is used to indicate the presence of special desirable attributes in the tea liquor which are detected by physical appearance, smell and taste. The biochemical properties of tea is very complex and is currently a subject of broad medicinal and toxicological studies. This study was conducted to determine the variation of selected biochemical properties (polyphenols, free sugars, and total proteins) of commonly growing tea cultivar (Camellia sinensis (L.) O. Kuntze), of TRI 2025 among all tea growing agro ecological regions in Mid Country of Sri Lanka. Fresh tea samples (two leaves and bud) were collected from same aged plants by using stratified sampling technique and samples from each stratum were selected randomly from different tea estates of each agro ecological region in Mid Country (WM1a, WM1b, WM2a, WM2b, WM3a, WM3b, IM1a, IM2a, IM2b, IM3a). Collected samples were placed on an ice and transported and oven dried at 50 ˚C for 12 hours and crushed in to fine particles. Methanol extraction was performed for the analysis of total polyphenol content and reducing sugars while phosphate buffer was used to extract samples for the analysis of proteins. The concentrations of polyphenols, proteins, and free sugars were determined by folin Ciocalteu reagent method, Lowry’s method and dinitrosalicylic acid method respectively with slight modifications. The findings of this study shown that biochemical properties of teas such as polyphenol, total protein and free sugars contents were significantly different (p <0.05) among many tea growing ago ecological zones in mid country of Sri Lanka. Maximum polyphenol, free sugar, total protein contents were recorded in WM1b, WM2a and IM2a respectively. Minimum polyphenol, free sugar, total protein contents were recorded in IM2a, IM3a and IM2a, respectively. This sets a precedent for the characterization of biochemical profiles of mid grown tea of Sri Lanka.
Determination of the Variation of Biochemical Properties of Selected Tea Cultivar (Camellia sinensis (L.) O. Kuntze) in Up Country
(Uva Wellassa University of Sri Lanka, 2019) Thiruneelan, T.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.; Samarasinghe, B.A.
Tea has an attractive aroma, good taste, and flavor, however; these properties could vary with climatic factors including temperature, sunshine hours and rain fall prevail in different agro-ecological zones in the growing areas. Therefore, this study was conducted to evaluate the chemical composition of Tea (camellia sinensis (L) O. Kuntze) var. TRI 2025 grown in different agro-ecological zones in Up-country. Fresh tea samples of TRI 2025 (two leaves & bud) were collected from the same aged plants by using stratified sampling technique from 11 regions, viz: WU1, WU2a, WU2b, WU3, IU1, IU2, IU3a, IU3b, IU3c, IU3d, and IU3e in the up country during the onset of rains. The fresh tea leaves were placed on ice immediately after harvesting and transported. The leaves were dried in an oven at 50 oC for 12 hours and dried samples were crushed in to fine particles. Methanol extraction was performed for the analysis of total polyphenol content and reducing sugars while phosphate buffer was used to extract samples for the analysis of proteins. The concentrations of polyphenols, proteins, and free sugars were determined by Folin Ciocalteu reagent method, Lowry’s method and Dinitrosalicylic acid method respectively with slight modifications. The findings confirm that chemical properties of tea in up country showed significant (p<0.05) difference among many tea growing ago ecological zones in Up-country of Sri Lanka. Maximum polyphenol, free sugar, total protein contents were recorded in IU3e, WU3 and WU1 respectively. Minimum polyphenol, free sugar, total protein contents were recorded in WU2a, IU3a and IU3c, respectively. This study sets a precedent for the characterization of biochemical profile of all tea growing areas in Up-country of Sri Lanka.
Development of a protocol for in-vitro propagation of black pepper (Piper nigrum L.) local selections
(Uva Wellassa University of Sri Lanka, 2015) Dissanayake, S.G.H.C.K.; Alwis, L.M.H.R.; Jayasinghe, H.A.S.L.; Attanayake, A.M.C.I.M.; Seneviratne, J.M.
Black pepper (Piper nigrum L.) belongs to family Piperaceae and it is one of the most economically important spice crops in the world (Srinivasan, 2007; Mathew et al., 2001). Unavailability of sufficient mother plant stock in the field, obtaining basal runners for propagation and less success and multiplication rate of the high yielding local pepper cultivars are the major problems faced by the farmers who cultivate. Being in vitro propagation a promising option, this study was focused to develop a suitable protocol for in vitro propagation of black pepper local selections. Methodology This research was carried out at Central Research Station, Department of Export Agriculture, Matale. Four experiments were conducted during the research period. Experiment one was conducted to find out the suitable surface sterilization method for the sterilization of black pepper shoot tips. Selecting of appropriate media for the culture establishment of black pepper shoot tips were carried out in second experiment using 1/3Murashige and Skoog (MS) medium and 1/2 Woody Plant Medium (WPM).Experiment three was conducted to find out suitable combination of auxin and cytokinin for the shoot multiplication of black pepper local selections. In fourth experiment, priority was given for the selection of best media and hormonal combination for the callus initiation of TG7 black pepper local selection. Full and half strength MS media were used as the culture media and two different concentration levels of kinetin and NAA were used as the growth regulators. Complete Randomized Design (CRD) was used as the experimental design. ANOVA was used to analyze the statistical difference of parametric data and non-parametric data were subjected for logarithmic transformation. SAS statistical software was used to analyze the data and mean separation was performed using Least Significant Difference (LSD). Results and Discussion As the results summarized in Table 1, sterilization using 10%- 20% Clorox for five to ten minutes (T1 to T5) showed higher percentages of bacterial contamination (40 to 80 %). Lower percentages of fungal contamination was observed in T4 to T8 within the period of three to five days (3% to 7%).The highest survival percentage (66.6 %) was reported in T8, 0.04 % HgCl2 for five minutes. Similarly, the lowest percentages of bacterial and fungal contamination were observed in T8. The highest percentage of phenolic browning (80%) was shown in T6 and lowest percentage of phenolic browning (10.0%) was observed in T2, i.e. 10% Clorox for 10 minutes within four to seven days.
Development of Osmotically Dehydrated Chips using Coconut Haustorium (Pelapi)
(Uva Wellassa University of Sri Lanka, 2013) Liyanage, M.L.K.; Jayasinghe, H.A.S.L.; Jayasundera, J.M.M.A.
Coconut palm (Cocosnucifera L.) is the most important crop in Sri Lanka. Coconut is germinated when it develops into the so-called 'apple' or haustorium. In most of the coconut kernel industries, a considerable amount of coconut haustoriums go waste. Osmotic dehydration (OD) is one of most important complementary pre treatment. This research was conducted to develop osmotically dehydrated chips using coconut haustorium and to find the most suitable packaging material. Experiments were carried out at the Coconut Research Institute, Lunuwila, Sri Lanka. Four types of osmotic solutions were used as, 45°, 55° and 65° Brix sugar solution and coconut treacle. Preliminary trials were carried out to find effect of osmotic agent and weight ratio on solid gain and water loss. Best geometry of haustorium chips was selected by visually. Size of 1 x 2 x 4 cm was selected. 45°, 55° and 65° Brix sugar solution were carried out for develop final products. Proximate composition and shelf life of the coconut haustorium chips with nylon LLDPE and TLAL packaging material were evaluated. Changes in sensory properties were determined by conducting the sensory evaluation. Developed product has low moisture content and high carbohydrate content. At the same time developed products were compared with others and 55° Brix –ODCHC was selected as the best product according to sensory evaluation. According to the shelf life studies, developed products can be stored in TLAl pouches under ambient temperature for more than 8 weeks. ODCHC can be used as a ready to eat snack food with good calorie value. Parametric data were analysed using Minitab 14 and SAS version 8 at p< 0.05 probability level and Microsoft Excel office package, 2010. Non-parametric data on sensory evaluation were analysed using Kruskal-Wallis Test.
Effect of palmyrah coir dust on physicochemical properties of potting media and on growth and yield of chilli
(Uva Wellassa University of Sri Lanka, 2015) Puthisigamani, S.; Jayasinghe, H.A.S.L.; Gunadasa, H.K.S.G.; Nilushiny, A.M.; Vijeindran, S.S.
Palmyrah (Borassus flabellifer) coir dust is a major by-product of the fibre industry. Coir waste or coir pith is generally a mixture of dust, bits and fibres of shortlength that is rejected during the process of coir extraction. Coir dust is a spongy material which can absorb ample quantity of water compared to its weight and it is a valuable carbon source which could be used in agriculture to maintain and improve the organic matter content of depleted soils(Vidhana Arachchi and Somasin, 1997). Organic matter can improve the soil properties in long run (Kularathne et al., 2005).Although Palmyrah coir dust is a very useful carbon source for agriculture, it is wasted by burning at the factory. No studies have been undertaken to investigate the beneficial effects of palmyrah coir dust which can be used in agriculture. This research was conducted to study the effect of palmyrah coir dust on physicochemical properties of potting media and on growth & yield of capsicum. Methodology A pot experiment was carried out at Palmyrah Research Institute, Jaffna under greenhouse conditions(temperature 30.1 C and relative humidity 80.9 % during day time). Six treatments were used: T1:-control (soil alone), T2:- palmyrah coir dust: soil (1:1), T3:- palmyrah coir dust: soil (1:3), T4:-palmyrah coir dust: soil: sand (2:1:1), T5:- palmyrah coir dust: soil: sand (1:2:1), T6:- palmyrah coir dust: soil: sand (1:1:2). The experiment was laid in a Complete Randomized Design (CRD) with three replicates. Hungarian Yellow Wax variety was selected as the test crop considering its short harvesting period.Potting media were prepared by mixing palmyrah coir dust, soil and sand in a different ratio on weight basis according to the treatments. All agronomic practices were undertaken according to the guidelines provided by the Department of Agriculture (DAO, 2006). Plant height (cm), crop yield (g), bulk density (g/cm ), porosity (%), water retention (% wt), pH, electrical conductivity (µs/cm), cation exchange capacity (meq/100g), available nitrogen (%), available phosphorus (%), organic carbon (%), exchangeable calcium (%) and exchangeable magnesium (%) were measured. Data was analyzed using SAS software package and the mean separation was done by Least Significant Difference (LSD) at p=0.05 probability level. Results and Discussion Significantly, the highest bulk density (1.41± 0.05 g/cm ) was recorded in the control treatment (T1). As given in Table 1, the lowest porosity (88.63 ± 0.05 %) and the lowest water retention (33.64 ± 0.05 %) were recorded in control treatment (T1). The highest porosity (95.75 ± 0.05 %) and the highest water retention (153.26 ± 0.05 %) were recorded in T4 treatment (palmyrah coir dust: soil: sand 2:1:1) followed by T5 treatment and T3 treatment at 5 % probability level. Palmyrah coir dust is a light weight material with low bulk density (0.128 g/cm ).Incorporation of palmyrah coir dust increased the porosity and water retention of potting media and reduced the bulk density.
Effect of Polybag Size on Growth and Physiological Attributes of Rubber (Hevea brasiliensis) Seedlings
(Uva Wellassa University of Sri Lanka, 2018) Gayashan, N.D.K.; Nayanakantha, N.M.C.; Seneviratne, P.; Senavirathna, A.M.W.K.; Jayasinghe, H.A.S.L.; Panditharathna, B.M.S.S.
The annual requirement of budded rubber plants [Hevea brasiliensis (Willd. Ex A. Juss.) Mull. Arg.] has increased. Currently, finding top soil for filling polybags has become an issue in raising rubber plants. Therefore, it is essential to find ways to minimize the amount of soil usage. The present study examined the effect of the size of polybag on growth attributes of rubber seedlings for an eight-week period. The experiments were conducted in the government rubber nurseries at Egaloya (Wet Zone, LW) and Monaragala (Intermediate Zone, IL). Six bag sizes with reduced volume (3" x 15",4" x 15", 5" x 15", 4" x 13", 5" x 13" and 6" x 13") as compared to the standard size (6" x 15"-control) were used for LW whereas five bag sizes (6" x 15", 6" x 16", 6" x 17", 7" x 16" and7" x 17") as compared to control (7" x 18") were used for IL. Germinated seeds were transplanted into each polybag filled with top soil and arranged in a nursery according to a randomized complete block design (RCBD). There were 60 replicate plants for each treatment. Growth and physiological attributes of seedling viz., stem height (cm), stem diameter(mm), number of leaves, chlorophyll content (SPAD value), leaf area (cm2), stomatal conductance (gs), tap root length (cm), tap root dry weight (g), total root dry weight (g) and shoot dry weight (g)were recorded after 8 weeks from transplanting. There was no significant (P > 0.05) difference in growth and physiological attributes of seedlings raised in reduced sizes of polybags when compared to those raised in the standard sized polybags in both agro-climatic zones during the experimental period. Therefore, there is a potential to use reduced sizes of polybags to raise rootstocks of rubber while reducing the amount of soil usage.
Effect of Propagator Height on Growth and Survival Rate of Black Pepper (Piper nigrum L.)at Nursery Stage
(Uva Wellassa University of Sri Lanka, 2018) Wijerathne, K.I.M.; Kumara, P.G.A.L.; Ranawana, S.R.W.M.C.J.K.; Jayasinghe, H.A.S.L.
Black Pepper (Piper nigrwn L.) is a spice belongs to family Piperaceae and known as the "King" of spices. Propagationthrough stem cuttings is the common practice.Before field planting, stem cuttings should be kept about 1.5 months inside the propagators and another two months under hardening process at the nursery stage. There is a need to identify the proper height of propagator which gives the highest growth and survival rate. Objective of the study was to increase the growth rate of pepper cuttings to produce field-ready plants within a short period of time by changing the propagator height. The experiment was conducted at the Central Research Station, Matale, Sri Lanka, during August to November 2017 and six different propagator heights (30, 40, 50, 60, 70, and 80 cm) were used as the treatments with 3 replications.Growth parameters such as number of leaves,shoot length, root length, number of roots and root volume and survival percentage were analyzed using ANOVA technique. Propagator with 50 cm height produced plants with significantly highest performance with respective to the above growthparameters except number of leaves compared to 60 cm propagator (current practice).Survival percentagesin 50 cm and 60 cm propagators are 99.3% and 98.6% and root volumes were 0.85 cm3and 0.73 cm3,respectively. Therefore, propagator with 50 cm height can be recommended to propagate pepper cuttings within shorter period of time in place of 60 cm propagator.
Evaluation of the Relationship between SPAD Reading and Biochemical Profile of Fresh Leaves of Selected Tea Cultivars (Camellia sinensis (L.) 0. Kuntze)
(Uva Wellassa University of Sri Lanka, 2018) Samarasinghe, K.G.B.A.; Jayasinghe, H.A.S.L.; Alakolanga, A.G.A.W.
Biochemicals in fresh tea leaves affect to the quality of made tea and are difficult to evaluate by traditional chemical extraction methods. Therefore, this study was conducted to investigate a simple method to evaluate foliar biochemicals using SPAD reading of three widely grown tea cultivars (Camellia sinensis (L.) 0. Kuntze), viz: TRI 2025, TRI 3035 and TRI 4046 in the Uva region. Fresh leaf samples of different developmental stages were randomly collected from Wewasse and Glen Alpine estates, Badulla. Leaves were placed in an ice box immediately after detaching from the bush and transported to Agricultural Chemistry laboratory of Uva Wellassa University. Study was conducted as two experiments during the period from July to December 2017. Average of five SPAD readings on each side of the midrib per leaf were taken to produce a single SPAD reading for each leaf. Leaves of each cultivar were categorized into seven samples according to the SPAD reading (i.e. SPAD 20, 30, 40, 50, 60, 70 and 80). Chlorophyll a, b and carotenoids were extracted and quantified in the first experiment while total polyphenols, reducing sugars and proteins were extracted and quantified in the second experiment. The relationship between chemical components and SPAD reading was estimated using regression analysis and Pearson Correlation coefficient. In the first experiment, the highest positive correlation (0.999) was recorded in between SPAD reading and total chlorophylls of cultivar TRI 3035. In the experiment 02, the polyphenols, reducing sugars and proteins of all cultivars were shown a strong, negative, non-linear relationship with SPAD reading (R2 > 0.90). The results revealed that the SPAD meter readings can be used to assess the relative chlorophyll content and approximate concentrations of the selected biochemicals in fresh tea leaves simply and non-destructively. Thus, the findings will be useful in the decision making of harvest time and quality control in tea sector.
Feasibility study for direct planting of in vitro potato (Solanum tuberosum L.) varieties Granola and Golden Star in aeroponic system
(Uva Wellassa University of Sri Lanka, 2015) Wijesinghe, A.P.; Alwis, L.M.H.R.; Jayasinghe, H.A.S.L.; Nugaliyadda, M.M.
The major constraints in potato cultivation are high seed cost, poor seed quality, unavailability of quality seeds at correct time for planting, frequent application of fungicides to control late blight disease, misappropriation of agrochemicals and limitation of suitable land. The total seed potato requirement in Sri Lanka is about 22,500mt per annum. Total annual importation of seed potato is about 7000mt and the Department of Agriculture produces about 400mt of high generation seed potato per annum. The rest of the seed potato requirement of about 60% is fulfilled by farmers own seed production. Seed potatoes are the most costly input having 53% of the total cost of production.Main objective is to study the feasibility of direct planting of Granola and Golden star in vitro plants in aeroponic system. Other objective is to identify the suitable liquid media for hardening of in vitro potato plants. Materials and method The planting materials which were used in research are In vitro potato plants, MS media, Albert solution and aeroponic system. First culture media was prepared for in vitro potato plants. Stock solution was measured to prepare MS medium. Then 0.1g of myo-inositol, 30g of sugar, 1g of charcoal and 9g of agar were measured and mixed well. Solution was diluted up to the 1l. pH was measured and adjusted up to 5.75. Culture bottles were filled by solution up to 30ml. Bottles were allowed for settle.In vitro plants were cut with node and cuttings were placed in culture bottles. Then bottles were labeled and placed in the culture room. Cultured bottles were kept for one month period. Half MS, full MS and Albert solution were prepared. pH was measured in MS solutions and adjusted to 5.75. Electrical conductivity was adjusted up to 1.7 in Albert solution. Six treatments were taken. (Golden star in 1/2 MS medium as treatment 1, golden star in MS medium as treatment 2, golden star in Albert solution as treatment 3, granola in 1/2 MS medium as treatment 4, granola in MS medium as treatment 5, granola in Albert solution as treatment 6) Data were collected at one week intervals. Mean shoot length, mean root length and mean number of roots were taken as the parameters. (In this research increment of growth was measured for each parameters) Albert solution was prepared for 250l of tank (EC-1.643 ms/cm). Electrical conductivity was adjusted up to the range of 1.5 to 2.0 ms/cm. Acclimatized plants were dipped in Thiram (2g/l). Then plants were placed in aeroponic system. Aeroponic system was adjusted to spray five second with once in five minutes at day time and once in fifteen minutes at night in first three days. Next four days system was adjusted once in ten minutes at day time and once in twenty minutes at night. After that system was adjusted once in twenty minute at day time and once in thirty minutes at night. EC was checked every day. Data were collected at weekly for seven weeks. Mean shoot length, mean root length, mean stolen length, mean number of stolen and mean number of tubers were taken as the parameters. (In this research increment of growth was measured for each parameters) Results and Discussion In both experiments collected data were analyzed by using minitab 16 under general linear model. According to the Table 1, the highest shoot length growth (3.13cm) was observed in variety Golden star with Albert solution (T3). Others are statistically different, but T6, T1 and T3 are comparable. Though T2, T4 and T5 are comparable but significantly lower than T3. When comparing mean length of root growth, there is no significant different in each treatment. Number of root increment are statistically significant each other. Therefore using of any treatment is not largely effect on root number or root length.
Improving of Adhesion in Laminated Rubber Glove Process and Incorporation of Recycled Coagulated Centrifuged Latex
(Uva Wellassa University of Sri Lanka, 2013) Lakmali, R.G.N.; Jayasinghe, H.A.S.L.; Ranasinghe, T.
As latex based product laminated glove is coming under household category use for the heavy duty purposes and for construction industry. Laminated Rubber sheet is used as a composite to palm area with textile fabrics (Kevlar, Cotton). The low adhesion causes to separate of laminated rubber sheet from the fabric and low quality. The emphasis was placed on enhance the adhesion ability while introducing of new method to incorporate recycled coagulated centrifuged latex with the laminated rubber sheet manufacturing. The research was conducted at the Workwear Lanka (Pvt) Ltd at Biyagama. Preliminary trails were based on common formulas of adhesive and the existing process line. To fix the accurate secondary solvent (SBP) amount and the accurate viscosity and the TSC of the adhesive, the amounts (SBP) were adjusted into 0ml, 50ml, 100ml, 200ml, 300ml and 400ml. Then modifications of the current process line by changing smoothing turns (one, two), maturing period (0.24, 48 hours), curing temperature (120,155,160 Ϲ), time (30,40,90 minutes) and the adhesive formula under different curing temperatures and times were done using modified adhesive blend to enhance the adhesion. Adhesion test was done for all experiments. Then the coagulated centrifuged latex (5kg) with high moisture content was recycled and incorporated it as the filler to the laminated sheet compound. Mechanical testing, moisture content and rheograph characteristics were measured, for the incorporated sheet and data were analyzed by using Tukey method and Dunnett test of MINITAB 16 statistical software. The adhesive blend with 200ml (SBP) has significant difference (p<0.05) among other treatments and the T16 process line has the significant different (p<0.05) among other process lines. The high wood resin amount with the lowest temperature and longest time period has the significant different (p<0.05) between each other treatment levels. There are no significant differences (P>0.05) the results of mechanical tests, rheograph characteristics and the moisture content between the existing and the incorporated laminated sheet. The best conditions for the highest adhesion ability are the 200ml, optimum SBP amount with 78.7 viscosity and 93.7 TSC value, double time smoothing, 24 hours maturing period,120 Ϲ low curing temperature, 90 minutes high curing time and with high amount of wood resin and there is a potential to incorporate of recycled rubber as the cost reduction filler ingredient.
Quantification of L-theanine Content of Two Selected Tea Cultivars [Camellia sinensis (L.) O. Kuntze] Grown in Sri Lanka
(Uva Wellassa University of Sri Lanka, 2020) De Silva, S.I.S.; Kaliyadasa, P.E.; Alakolanga, A.G.A.W.; Jayasinghe, H.A.S.L.
L-theanine is an abundant non-protein amino acid that accounts for more than 50% of the total free amino acid in the green tea leaves, having various pharmaceutical importance. The study was conducted to determine the variation of L-theanine content of commonly growing tea cultivars, TRI 2025, and TRI 4053 among all tea-growing agro-ecological regions in Up, Mid, and Low Country of Sri Lanka, concerning one month before and after the onset of rainfall periods. Fresh tea leaves were collected from same-aged plants by using stratified sampling techniques and samples from each stratum were selected randomly from different tea estates of each agro-ecological region in all three elevations of Sri Lanka. Collected samples were oven-dried at 50℃ for 12 hours and hot water (85℃) was used to extract L-theanine from fresh tea leaves. The High-Performance Liquid Chromatographic technique with ultraviolet detection (RP-HPLC-DAD-UV) was optimized and validated to quantify L-theanine content according to conditions of Csupor’s method with slight modifications. Data acquisition and evaluation were performed using Chromeleon software. The findings of this study showed that the total Ltheanine contents (gg-1%) were significantly different (p < 0.05) among the tea growing agro-ecological regions in both TRI 2025 and TRI 4053 in Up, Mid and Low Country of Sri Lanka. The highest total L-theanine contents were recorded in IU3d, WU2b, and WL1b-E1 of TRI 2025 and IU3a, IM3a, and WL2a-E3 of TRI 4053 in Up, Mid and Low Country respectively. Significant variation in total L-theanine content in TRI 2025 and TRI 4053 in all three major elevations one month before and after the onset of rainfall was observed. Total L-theanine content (gg-1 %) was ranged from 0.04 - 7.96% in all three elevations in Sri Lanka and it was higher than reported values from Kenya. This study evident that Ceylon tea is having higher quality in terms of L-theanine content. Keywords: Agro-ecological regions, Low country, Mid Country, Total L-theanine, Up Country
Selection of an effective biofilmed biofertilizer formulation and best potting medium for anthurium (Anthurium andraeanum)
(Uva Wellassa University of Sri Lanka, 2015) Rathnayake, R.M.D.C.; Gunadasa, H.K.S.G.; Jayasinghe, H.A.S.L.; Seneviratne, K.A.C.N.
Anthurium is identified as one of the crops prioritized for the development and export promotion in Sri Lanka (Kelegama, 2001). Optimum growth and flowering of Anthurium mainly depend on potting medium, fertilizer and light levels (Higaki et al, 1994). Potting medium rich in nutrients and effective fertilizers can be used for the optimum growth of this plant. Beneficial biofilm based biofertilizers called biofilmed biofertilizers (BFBFs) have been introduced recently (Seneviratne et al., 2010). Present study was focused to select an effective biofilmed biofertilizer formulation and evaluate the comparative effect of different potting media on vegetative growth of Anthurium andreanum plant. Methodology The present study was carried out at the Royal Botanic Gardens, Peradeniya. Two experiments with different treatments were conducted during this study. First experiment was conducted under shade house conditions with different fertilizer treatments; 50 % chemical fertilizer (CF), 50 % CF + BFBF and100 % CF recommended for Anthurium was selected as the control. In the second experiment, four different potting media (inert particle mixture, coir chips, leaf litter with sand, control) were used and the existing potting medium, which was used at the Royal Botanic Gardens, Peradeniya was taken as the control. Different BFBF with 50 % CF application was under taken at one week interval for the plants of the first experiment and 50 % CF application was under taken at one week interval for the plants of second experiment. Initial data were collected before the plants establishment and final vegetative growth parameters were measured after three months of plant establishment in both experiments. Plant height (cm), plant weight (g), total root length (cm), leaf number, leaf area, root number and the chlorophyll content were considered as the vegetative growth parameters. Treatments were arranged in a Complete Randomized Design (CRD). Mean separation was conducted using the Tukey method (P< 0.05). MINITAB 16 statistical package (Minitab Inc.) was used for data analysis in both experiments.
The Shoot Growth Pattern of Tea (Camellia Sinensis) During Different Stages of the Pruning Cycle
(Uva Wellassa University of Sri Lanka, 2012) Abeyrathna, O.P.I.A.; Wijerathne, T.L.; Gunathilaka, R.P.D.; Jayasinghe, H.A.S.L.
Tea (Camellia sinensis) is a woody ever green perennial tree. Different tea cultivar has different growth characteristics. The shoot replacement cycle is a measure of the time taken (days) for an axillary bud to grow into a shoot suitable for harvesting when released from apical dominance (Carr, 2000). There are three principal yield components in tea, namely the number of shoots harvested (per m2), the mean shoot dry mass at harvest (g) and the time taken for an axillary bud to grow into a shoot suitable for harvesting (Carr, 2000). Tea shoot growth varies with the clone, the season, inputs such as nitrogen (N), and stage in the pruning cycle. According to the hand book on tea the removal of leaf bearing branches in a tea bush at a given height is called pruning. This may also affect the pattern of shoot growth too. Investigating shoot growth pattern and factors affecting are very help full to determine the suitable plucking policies (Wijeratne, 2001) and it may also help to decide the other management practices to maximize the yield.
Study on Induced MutTION nd Development of Media Protocol for Plant Regeneration from Mutated Calli of Lily(Lilium longiflorum L,)
(Uva Wellassa University of Sri Lanka, 2010) Jayasinghe, H.A.S.L.; Shirani, D.A.; Kaliyadasa, P.E.
The study was carried out to create novel types of Lilium longiflorum by using irradiated calli to cater the increasing demand for Lilium as one of the most important bulbous flower commercially grown in Sri Lanka. The calli were induced from lower half of the bulb scales and the basal part of the in-vitro plants in MS medium supplemented with three different combinations of BAP, IBA and 2, 4-D in the first experiment. Data were recorded on callus induction frequency, minimum days taken to appear callus, percentage of calli without direct organogenesis, growth rate and diameter of calli. In the second and third experiments, the calli were subjected to irradiation with different exposure time (10, 20, 30 and 40 minutes exposure) of UV (254 nm) and 6°Co gamma (2.5, 5 and 10 Gy) and cultured on MS medium with three different hormone combinations of BAP, NAA and GA3. Observations were made on mortality percentage of calli after irradiation, number of calli producing shoots, total number of shoots and shoot height. All the treatments were assigned in Complete Randomized Design with two factors. Each treatment of experiment 1 was consisted with 20 replicates & treatments of experiment 2 and 3 were consisted with 15 replicates. The data were analyzed using statistical package MINITAB. It was found that lower half of bulb scales cultured on MS supplemented with 0.022 mg/I BAP and 0.22 mg/I 2,4-D recorded least number of days (22 days), highest frequency of callus induction (85%), highest percentage of calli without direct organogenesis (82.35%), diameter (1.8±0.12 cm) and growth rate (3.3±0.30) at P<0.05. In Experiment 2 & 3 interaction effect of media and irradiation source was not significant at p<0.05. Irradiation levels with reduced plant height mean no of shoots and mortality less than 50%, considered as an indicator for mutations, UV with 30 minutes exposure time and 10 Gy of gamma can be selected as effective sources of mutation which recorded the lowest values for above parameters at p<0.05. At the same time mutated calli from above irradiation levels in the MS supplemented with 0.5 mg/I NAA and 0.6 mg/I BAP recorded the significant growth than other media (p<0.05). Key words: BAP, 2,4-D, NAA; Gamma radiation, UV radiation
Use of Growth Regulators to Induce Shoot Production of Anthurium (Anthurium andraeanum)
(Uva Wellassa University of Sri Lanka, 2013) Niroshika, H.A.D.; Jayasinghe, H.A.S.L.; Kularatne, M.A.; Disanayake, D.W.A.J.
Anthurium andraeanum is an economically important tropical cut flower species belongs to family Araceae and becoming more popular in the world cut flower industry due to its high varietal diversity and long vase life (Grayum, 1990; Anonymous, 2010). Anthurium ideally suits with the Sri Lankan climatic conditions and encompasses both domestic as well as international trade. However, the absence of efficient propagation methods to produce quality planting material has become a major constraint for the small scale Anthurium growers. The conventional propagation methods such as basal suckers and stem cuttings are not efficient for the commercial production. On the other hand, tissue culture technology is not a cost effective for local growers. Different studies have shown that exogenous application of cytokinin such as Benzylaminopurine (BAP) and gibberellic acid (GA3) has a significant effect on lateral shoot production of topped plants of many species. Therefore, the ability of the Anthurium plant to produce lateral shoots through hormones stimulation was studied to disclose an efficient propagation method for Anthurium. Methodology The study was carried out inside a shade house, which had 80 % level, at Regional Agricultural Research and Development center, Makandura. About two years old uniform size Anthurium plants with stems grown up to 15 cm height. Two varieties, M30 and M36 were obtained as planting materials and the study was arranged as two experiments in variety wise. After one month of planting the top of selected plants with two to three roots were removed (topped). The remaining basal parts with three to four leaves were treated with seven different combinations of GA3 and BAP concentrations. Treatments consisted of four foliar runoff sprays of three different sole GA3 concentrations (T2, T5) on consecutive weeks and combination of those GA3 concentrations with three different BAP concentrations(T3, T4, T6, T7) on alternative weeks.

Browsing by Author "Jayasinghe, H.A.S.L."

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