DSpace 7

DSpace is the world leading open source repository platform that enables organisations to:

easily ingest documents, audio, video, datasets and their corresponding Dublin Core metadata
open up this content to local and global audiences, thanks to the OAI-PMH interface and Google Scholar optimizations
issue permanent urls and trustworthy identifiers, including optional integrations with handle.net and DataCite DOI

Join an international community of leading institutions using DSpace.

The test user accounts below have their password set to the name of this software in lowercase.

Demo Site Administrator = dspacedemo+admin@gmail.com
Demo Community Administrator = dspacedemo+commadmin@gmail.com
Demo Collection Administrator = dspacedemo+colladmin@gmail.com
Demo Submitter = dspacedemo+submit@gmail.com

Photo by @inspiredimages

Communities in DSpace

Select a community to browse its collections.

Now showing 1 - 5 of 5

Recent Submissions

Intraspecific diversity of elaeocarpus Montanus Thwaites in Sri Lanka, based on molecular data
(University of Peradeniya, Sri Lanka, 2024-08-29) Hapuarachchi, S.I.; Silva, G.G.N.D.; Yakandawala, K.; Yakandawala, D.M.D.
Elaeocarpus montanus Thwaites (family Elaeocarpaceae) is a medium-sized tree with nearly globular, tinged red brown colour fruits confined to the montane forests of Sri Lanka. A recent morphometric study carried out on the genus Elaeocarpus in Sri Lanka, based on field collected samples, revealed morphological variations among populations within the species, recognizing three phenetic groups. Given its status as an endemic species classified as vulnerable on the IUCN Red List 2020, a comprehensive taxonomic study is imperative for the conservation of E. montanus in Sri Lanka. Hence, the current study was aimed to reassess the phenetic groups identified through morphometric analysis and to establish a phylogenetic framework for confirming the monophyly of E. montanus, employing molecular sequence data. Three specimens were collected from each population, representing the three phenetic groups. The genomic DNA extractions of fresh leaf samples were carried out using the modified CTAB method with an addition step of sorbitol pre- washing. The trnL-trnF, ITS, matK and trnH-psbA regions were PCR amplified and sequenced. Phylogenetic trees were constructed based on Maximum Parsimony method, along with model-based methods, Maximum Likelihood and Bayesian Analysis. Elaeocarpus angustifolius was used as the out group. Although the E. montanus was supported as a monophyletic taxon in all analyses, the populations within the species representing the three phenetic groups, even though resolved as separate clades, were weakly supported (Posterior Probability less than 0.005) and unresolved. The sequence diversity in the selected barcoding regions was not adequate (genetic distances less than 0.002) to support the phenetic grouping. Therefore, a detailed molecular analysis of populations is necessary to reveal the levels of population diversity, isolation and the taxonomic position of E. montanus.
Mango in Sri Lankan homegardens: how predominant are they?
(University of Peradeniya, Sri Lanka, 2024-08-29) Kuruppuarachchi, N.; Lowe, W.A.M.; Silva, G.L.L.P.; Pushpakumara, D.K.N.G.; Weerahewa, J.
Mango (Mangifera indica L.), is a fruit tree with significant importance in Sri Lanka, is cultivated both in orchards and homegardens. These homegardens, similar to secondary forests, host mango trees through natural regeneration or household interventions. Demanding minimal management, mango provides nutritional support and a valuable income source to households. They also contribute in carbon storing and offer various ecosystem services. The study was conducted through a survey which encompassed 435 homegardens across four districts in Sri Lanka representing 16 agro-ecological-regions. Mango tree diversity was assessed in terms of abundance, dominance, density and similarity to evaluate the prominence level of mango trees in the homegardens. Mango trees were observed in 85%, 59%, 87% and 60% of the homegardens respectively, in Hambantota, Jaffna, Matale, and Ratnapura districts accounting a total of 965 mango trees in 313 homegardens. This represents 25% of fruit trees recorded in homegardens. Average number of mango trees/homegarden ranged from two to five, where Hambantota district exhibiting the highest average. Mango trees were found as the second most prevalent plant species in homegardens in both Hambantota and Jaffna, while ranking at fourth and fifth prevalence levels in Matale and Ratnapura, respectively. The majority of mango trees (64%) were dominating the understory of homegardens. Compared to the other tree crops, mango demonstrated a higher density, occurrence, dominance, and similarity in Jaffna, attributed to lower species-richness and tree-abundance. Furthermore, above-ground biomass (AGB), diameter-breast-height, and basal-area of mango trees varied across the districts, thus contributing differently to total AGB. Overall, homegardens in Sri Lanka play a crucial role as vital reserves for population and diversity of mango trees, potentially preserving unique genotypes through the efforts of custodian farmers. Providing guidance on proper care and effective management practices for mango trees in homegardens can yield a range of economic and environmental benefits.
Microbiological quality assessment of the poultry broiler starter feed
(University of Peradeniya, Sri Lanka, 2024-08-29) Gallage, H.C.; Karunarathna, Ruwani; Karunarathna, H.M.T.K.; Weerasinghe, L.A.D.E.; Samita, S.; Kalupahana, R.S.; Kottawatta, K.S.A.
The poultry feed industry has grown as a large-scale industry in Sri Lanka. Amidst the growth in the industry, producing high quality and safety feed is important. Biological contaminants; bacteria and fungi are the key causes for feed deterioration, and diseases in poultry. Thus, this study aimed to investigate the microbiological quality of 32 broiler starter feed samples, considered to one feed brand, collected from eight feed distributors and their 24 feed-supplying farms in Kurunegala district. The samples were processed for detection of Enterobacteriaceae (ENT) count, aerobic plate count (APC), and Salmonella spp as per the ISO and SLS guidelines. Lacto Phenol Cotton Blue (LPCP) staining was performed to identify the fungi species. According to the EU safety levels, the ENT, APC, and moulds of poultry feed should be present below 300 cfu/g, 1.0×10⁶ cfu/g, and 1.0×10⁶ CFU/g respectively, and Salmonella should be absent as per both EU and ISO standards. The ENT of one sample at the distributor stage exceeded 300 CFU/g. None of the samples were positive for Salmonella. The APC varied between 4.3×10³ and 1.9×10⁵ CFU/g, giving the mean APC of 6.4×10⁴ CFU/g and 1.3×10⁵ CFU/g at distributor and farm levels. Aspergillus spp, Penicillium spp, and Rhizopus spp were identified from the cultured feed at the distributor stage and the count varied between 1.0×10² and 3.0x10² CFU/g whereas Mucor, Cladosporium spp, and Scopulariopsis spp, were additionally identified from farm level feed samples, and count varied between 1.0×10² and 2.1×10³ CFU/g. The TBC and the fungi count were significantly different (P< 0.0001 and P=0.01) at the farm stage. Although the TBC and the fungi count at the farm stage are within the safety levels, there is suggestive biological contamination. Further, the diversity of the moulds present in the feed samples indicates the environmental contamination of the processed feed.
Molecular characterization of neopestalotiopsis species associated with Camellia Sinensis from selected tea plantations in Sri Lanka
(University of Peradeniya, Sri Lanka, 2024-08-29) Weerasekara, I.T.; Udayanga, Dhanushka; Manamgoda, Dimuthu S.; Mapa, Sumudu; Castlebury, Lisa A.
Tea [Camellia sinensis (L.) O. Kuntze] is an important commercial crop cultivated in many countries such as China, India, Sri Lanka and Kenya to produce the renowned beverage called “tea”. Immature leaves and buds are utilized in the production of tea and hence it is vital to maintain health of the tea foliage to maintain optimal quality and quantity of tea yield. “Gray blight” is a destructive fungal disease caused by Pestalotiopsis-like taxa, affecting tea leaves. In this study, several Pestalotiopsis-like taxa were isolated from tea leaves exhibiting gray blight symptoms from the major tea cultivation zones of Sri Lanka including Southern, Uva, Central and Sabaragamuwa provinces. The genetic diversity of the isolates initially identified as Neopestalotiopsis spp., based on morphology and internal transcribed spacer 1, 5.8S and the internal transcribed spacer 2 of the ribosomal RNA gene cluster (ITS) sequence data were assessed by multigene phylogenetic analysis of the specific gene regions ITS, partial sequences of β-tubulin (TUB2) and translation elongation factor 1- α (TEF1-α). Results revealed that Neopestalotiopsis clavispora, N. petila, N. saprophytica, N. hydeana and N. surinamensis distributed over eight tea plantation sites in Sri Lanka. However, phylogenetic identification of some fungal isolates remained ambiguous due to unstable topology of the multigene phylogram of this genus. In pathogenicity assays, all of these species induced typical gray blight lesions on artificially inoculated tea leaves confirming Koch’s postulate. Among the identified isolates, only N. clavispora has been recorded previously as a gray blight associated fungal pathogen in C. sinensis globally, yet not within Sri Lanka. Also, this study confirmed that the cause of gray blight disease is not confined to a single pathogenic fungal species, but rather a complex of fungi.
Modified low-cost growth medium for spirulina platensis using cow dung tea
(University of Peradeniya, Sri Lanka, 2024-08-29) Rathnayake, R.; Wijesundara, A.L.S.S.
Spirulina platensis, a filamentous cyanobacterium, has garnered attention for its nutritional and potential health benefits. It has been utilized in the food, pharmaceutical, and cosmetic industries as well as in high-value products. While Zarrouk’s medium is commonly used as the standard medium for Spirulina cultivation, its large-scale adoption is hindered by higher procurement expenses. This study aimed to develop a low-cost medium using cow dung tea for cultivating S. platensis biomass, derived from the anaerobic digestion of cow dung which comprises essential nutrients for S. platensis growth. Spirulina platensis was cultivated in 20 g/1L cow dung tea medium with sodium bicarbonate, sodium chloride, and urea in four different concentrations, prepared by adjusting the nitrogen sources, with three replicates (medium B, D, E, F). The algae were grown 24 hrs under illumination (3000 lux CFL bulb), and the temperature was maintained at 25±2°C inside the culture unit, with continuous shaking using an orbital shaker. Growth was monitored for 20 days, with optical density readings taken every three days at 680 nm, and chlorophyll concentration and dry weight measured every five days. Nutrient uptake (nitrogen, phosphorus) and physicochemical parameters (pH, conductivity) were also recorded to track S. platensis growth. Normally distributed growth data were analyzed using one-way ANOVA. After a 15-day culture period, it was found that a 50 ml jar containing 20 g/1L cow dung tea medium supplemented with 0.4 g sodium bicarbonate, 0.25 g sodium chloride, 0.01 g urea fertilizer, and 0.05 ml micronutrients (medium E) was the best low-cost alternative medium out of the four tested mediums for Spirulina platensis, exhibiting maximum specific growth rate (μ=4.5774 ± 0.5813), dry weight (5.036±0.405g/L), total biomass (316.307mg/L), and chlorophyll ‘a’ content (5.441 ± 0.26μg/ml), respectively, under laboratory conditions. It is 4.8 times more profitable and yields higher compared to Zarrouk’s medium.