Sriyani Edussuriya Peiris

• BSc, MS,PhD
• Professor (Full) at Sri Lanka Institute of Information Technology

This study investigates the application of silver/iron-titanate (Ag/Fe-TiO2) nanoparticles (NPs) as a sterilizing agent for in vitro cultures of Dracaena sanderiana cultivars 'Gold' and 'Victory'. The motivation behind this research is to find an effective sterilization method that does not harm plant growth. The Ag/Fe-TiO2 NPs, activated by visibl...

Most types of metal nanoparticles exhibit anti-bacterial properties. Copper nanoparticles can generate reactive oxygen species (ROS) within bacterial cells, initiating a cascade of events that lead to bacterial cell death. In this study, copper nano units (Cu NUs) were synthesized through green synthesis method using anthurium leaf extract toward t...

Red seaweed, Gracilaria species are the main source contributing around 80% of the world’s agar production. In-vitro propagation of seaweed can contribute immensely to increase production of agar. Gracilaria hikkaduwensis and Gracilaria corticata are two potential sources of raw material for agar production and in vitro propagation can be used for...

Bacterial blight in Anthurium andraeanum Lind. which is caused by Xanthomonas sp. is regarded as the most threatening disease in the anthurium industry worldwide. Therefore, the current study was carried out to determine whether the application of copper nano particles (CuNPs) and sulfur nanoparticles (SNPs) is a possible solution to control the ba...

Visible light (VL) active silver decorated iron titanate/titanium dioxide (Ag‐FeTiO3/TiO2) nanohybrids derived from natural ilmenite sand effectively cleanse the exophytic plant pathogens in explants grown by in vitro techniques. VL active nanohybrid is synthesized by acid‐hydrolysis of natural ilmenite, followed by precipitation of the lixivium an...

Anthurium blight is caused by Xanthomonas spp. which is regarded as the most threatening disease to the anthurium industry worldwide. Therefore, the current study was carried out to determine whether the application of sulphur nanoparticles (SNPs) is a possible solution for treating anthurium cultivars infected with Xanthomonas spp. The bacterium X...

Caladium bicolour (Aiton) Vent. is an attractive commercial ornamental plant in the horticulture industry which is popular as potted plants for homescaping and as garden plants for landscaping. Propagation of this attractive plant through micropropagation has more benefits than conventional propagation. The current study describes an in vitro multi...

Dianella tasmanica 'variegata' is one of the popular species which is exported as ex-agar plants from Sri Lanka. In order to promote dianella exports, micropropagation should be increased to produce a high-quality large number required by the export markets. However, severe microbial contaminations in the in vitro establishment have become the bott...

The applications of photocatalytic nanomaterial technology received intense scientific focus with the advent of nanotechnology. Applications based on TiO2 nanoparticles have shown promise of photocatalytic efficiency among many semiconductor metal oxides. Titanium dioxide is utilized in many practical applications such as water and air purification...

Osbeckia octandra (Heen Bovitiya), which is one of the most valuable ayurvedic medicinal and ornamental plant in Sri Lanka, is now threatened due to its overexploitation from their natural habitat. In order to produce high quality, disease-free and genetically identical plant materials in large scale, we developed a highly efficient in vitro clonal...

Osbeckiaoctandra (HeenBovitiya), which is one of the most valuable ayurvedic medicinal and ornamental plants in Sri Lanka, is now threatened due to its overexploitation from their natural habitat. In order to produce high quality, disease-free and genetically identical plant materials in large scale, we developed a highly efficient in vitro clonal...

Orchids have a great demand in local and export markets as cut flowers and potted plants. A large amount of clonal plants can be produced through micropropagation to meet this flourishing demand. However, a significant amount of plants is losted during acclimatization phase of micropropagation as the environmental change is abrupt. Hence this study...

Stevia rebaudiana is a non-caloric sweetening herb, which has a high potential for commercialization. During this study low cost media sterilization, seesap (CSUP) technique which applies sodium hypochlorite was used as an alternative to autoclaving. In vitro cultures were established using nodal segments collected from stevia mother plants. These...

Breadfruit (Artocarpus altilis) is a traditionally cultivated food crop, propagated using root shoots or root cuttings. The number of root shoots produced by a tree is limited. In vitro propagation offers a method which breadfruit can be quickly propagated, distributed and meet international quarantine requirements Therefore, this study was conduct...

Breadfruit (Artocarpus altilis) is a traditionally cultivated food crop, propagated using root shoots or root cuttings. The number of root shoots produced by a tree is limited. Therefore, this study was conducted with the objective to optimize in vitro establishment of A.altilis for rapid propagation. Axillary shoots produced after decapitation of...

An experiment was carried out to determine the effect of graded nitrogen levels on three dracaena (Dracaena sanderiana L.) varieties viz. ‘Gold’, ‘Victory’ and ‘White’ at the Eastern University, Sri Lanka . Plants were grown at 70% shade house. Nitrogen doses used were 0.5, 1.0, 1.5, 2.0 g/plant/ month. Completely randomized design was used as expe...

Bloom’s Taxonomy is widely used , to bring out thinking ability in students , as an assessment method. In this article we emphasize on four types of methods popularly used in assessing intended learning outcomes in written examinations. How questions should be structured in e ach leve l of cognitive domain is discussed with an example in...

The culture medium for in vitro propagation of orchid influences the shoot multiplication, growth of shoots and roots immensely. Though Murashige & Skoog (MS) medium is widely used, stock solution preparation is required for lowering cost against MS powder. Since, calculations and proper sequence of mixing are involved with stock solution preparati...

Quality Information Systems (QIS) provides quality related information to stakeholders. In e-learning applications, QIS should provide e-learning materials to the lecturers and the learners those who use them. In Student Management Systems (SMS), QIS provide all the facilities to run the administrative functions smoothly. Electronic Research Reposi...

The objective of this study was to investigate the effectiveness of teaching methods on students' academic performance and to understand what measurements that someone could apply to improve the learning process. In the past our understanding was to measure teaching as the most important factor but at present the learning factor is more important....

Today's students are changing far more rapidly than the colleges and universities that recruit them. They have a preferred mode of activity and interaction that is not in sync with an educational system that is showing its age. " Net Gen " students are not interested in large lecture halls, preferring informal, and small-group discussion, often thr...

Cryptocoryne wendtii is commonly used for aquaria and water gardens and hence is an economically important aquatic plant with a high demand in local and export markets. There are fifty species of genus Cryptocoryne out of which fourteen species including C. wendtii are endemic to Sri Lanka. Although Sri Lanka exports around 300 aquatic plants, expo...

Exacum trinervium was regenerated through axillary bud proliferation, direct organogenesis without intervening callus phase or indirect organogenesis through callus from leaf explants. Leaf explants cultured on MS medium with 1 mg L-1 BAP produced 12.66±2.00 shoots per explants while calli initiated on MS with 2 mg L-1 2,4 D produced average of 6.3...

Rosa pinna ( Clerodendrum philippinum Schaue r), is a shrub with attractive and fragrant flowers. However, the tall and spread architecture and high leaf to flower ratio hinder its use as an ornamental plant. Hence, changing the level of acceptance of C. philippinum by incorporating a dwarfing gene to the plant is considered useful. A study was con...

The effects of different concentrations of colchicine on shoot and root development of nodal explants and germinating somatic embryos of Hemidesmus indicus (L.)R. Br. (Iramusu) was investigated. MS medium solidified with 8 g/l agar was superior to the liquid medium in all the concentrations of colchicine. In nodal derived H. indicus plants, the hig...

An experiment was conducted in a shade house to determine the effects of three shade levels on leaf area and biomass production of three varieties of dracaena (Dracaena sanderiana L.) in the dry zone (Batticaloa district) of Sri Lanka. 'Gold', 'Victory' and 'White' varieties were arranged in 50%, 70% and 80% shade levels as a CRD. There was a signi...

Production of attractive marketable poinsettia ( Euphorbia pulcherrima ) pot plants throughout the year can be achieved by forced blooming in the off season, but it is necessary to study their post production conditions and public acceptability prior to marketing. The poinsettia pot plants produced in the off season, when evaluated on its acceptabi...

The ability of in vitro micropropagtion to produce high quality planting material in large quantities is hindered by their high cost of production. Hence the price of planting material is high, making them unaffordable to growers. However, a larger portion of the capital and running cost of micropropagation can be reduced using CSUP (pronounced as...

Poinsettia (Euphorbia pulcherrima Willd) is a popular pot plant in many countries and there is a high potential to introduce it to the Sri Lankan floriculture markets. Naturally, poinsettia becomes colourful under short day conditions. However, artificial induction of flowers is necessary for it to produce marketable plants throughout the year. In...

The production of new varieties and higher quality products from Echinacea spp. requires a greater understanding of the regulation of plant growth and the production of specific phytometabolites. The current studies were designed to generate elite varieties of Echinacea purpurea based on regeneration efficiency and chemical profile. Clonal propagat...

Flowers of Nymphea stellata Willd., like other water lilies, are subject to circadian clock-controlled petal closure in the afternoon. To investigate the effects of plant growth regulators, and various other chemicals, inarresting nyctinastic movement (petal closure), cut flowers of N. stellata were exposed to different concentrations of gibberelli...

In recent years the quest for longevity and an improved quality of life has ventured into the realm of natural therapeutics, resulting in a wider acceptance of plant-based medicine in the Western world. This increased interest in natural remedies has also brought about the great challenge of maintaining a balance between the demand of expanding mar...

Gamma-aminobutyrate (GABA) is a ubiquitous four-carbon, non-protein amino acid synthesized by glutamate decarboxylase. Previous research suggests that the endogenous synthesis of GABA, a naturally occurring inhibitory neurotransmitter at neuromuscular junctions, serves as a plant resistance mechanism against invertebrate pests. In this study, two h...

Glutamate decarboxylase (GAD, EC 4.1.1.15) catalyses the α‐decarboxylation of glutamate to produce γ‐aminobutyrate (GABA). The nucleotide sequences of two divergent GADs (designated GAD1 and GAD3) were isolated from a Nicotiana tabacum L. cv. Samsun NN leaf cDNA library. Open reading frames indicated that GAD1 encodes a polypeptide of 496 amino aci...