University of Peradeniya

About: University of Peradeniya is a education organization based out in Kandy, Sri Lanka. It is known for research contribution in the topics: Population & Poison control. The organization has 5970 authors who have published 7388 publications receiving 197002 citations.

Quantification of groundwater–seawater interaction in a coastal sandy aquifer system: a study from Panama, Sri Lanka

Abstract: The Panama coastal aquifer system is an important water resource in the southeast coast of Sri Lanka that provides adequate supplies of water for agriculture and domestic uses. One of the biggest threats to these fragile aquifers is the sea water intrusion. In this study, recharging mechanism and geochemical evaluation of groundwater in the coastal sandy aquifer of Panama were evaluated using chemical and stable isotope techniques. Thirty groundwater samples were collected and analyzed for their major ion concentrations and stable isotope ratios of oxygen (18O/16O) and hydrogen (D/H). All studied samples showed a ranking of major anions in the order Cl− > HCO 3 − > SO 4 2− > N-NO3 − while cations showed a decreasing order of abundance with Na+ > Ca2+ > Mg2+ > K+. Dominant groundwater hydrogeochemical types were Na–Cl and mixed Ca–Mg–Cl. Results of saturation index calculations indicate that the investigated groundwater body was mostly saturated with respect to calcite, dolomite and gypsum. In addition, stable isotope and geochemical data suggest that fresh groundwater in the aquifer is recharged mainly by local precipitation with slight modification from evaporation and saline water intrusions. Isotope data suggest that mixing of salt water with freshwater occurs in aquifers which are located towards the lagoon. Since the communities in the study area depend entirely on groundwater, an understanding of the hydrogeochemical characteristics of the aquifer system is extremely important for the better water resource management in the region.

Emerging non-thermal technologies for decontamination of Salmonella in food

Abstract: Background Salmonella infection has become a foremost health issue as it is the causative agent of several foodborne outbreaks. Currently, there is a huge demand for safe, healthy, and nutritious, fresh-like food products. It strongly suggests the food manufacturers to develop appropriate practices like expeditious testing, detection, and inactivation of foodborne pathogens as well as to prevent the pathogen entry into the supply chain. Scope and approach In this decade, a lot of innovative ideas and technologies have been investigated as a substitute for conventional thermal technologies employed to inactivate foodborne pathogens. This review presents the potential of such technologies for instance, cold plasma, light-emitting diode, ozone, ultrasound, and pulsed electric field in decontaminating the Salmonella in food production and supply chain. These emerging innovative decontamination practices not only ensure the freshness of food but also enhance the microbial safety and quality of a food product. The synergistic effect of the cold plasma technique arrests the pathogenic cells’ viability and multiplication. Oxidative response and the free radical generation capability of ozone treatment destroy the bacterial cells and accord antimicrobial activity. Applications of acoustic cavitation mechanism of ultrasound and non-ionizing electromagnetic radiations of UV light progressively inactivate the pathogenic microorganisms. The high-intensity usage of electric field strength by utilizing the electroporation method resulting in microbial cell death. Key findings The effect of emerging non-thermal technologies and the processing parameters involved in the decontamination have been reviewed comprehensively along with the summary of different food products. A thorough understanding and deep insights into the mechanisms underlying the optimization of the process conditions will pave the way for upscaling these technologies for improved quality and sustaining the nutritional components of the food product.

Growth and phosphorus nutrition of rice when inorganic fertiliser application is partly replaced by straw under varying moisture availability in sandy and clay soils

Abstract: The combined effects of (1) reduced soil moisture availability, (2) reduced application of inorganic fertilisers while incorporating straw, (3) soil type, and their effects on growth, root system plasticity, phosphorus (P) nutrition of rice, and soil P dynamics are poorly known, but very important when aiming to increase the efficiency of water and P use. Using large pots a three-factor factorial experiment was conducted with two moisture treatments (i.e. continuous flooding, and draining of top soil after flowering while subsoil was kept moist through capillary action), three fertilisation treatments; with (P1) and without (P0) applications of inorganic P fertilisers, and 25 % of inorganic fertilisers reduced while incorporating straw (5 t ha−1), and soil type (i.e. clay and sandy soils with 15 and 9 mg P kg−1 soil, respectively in P0). Shoot and root growth, root system plasticity, P nutrient status and soil P dynamics were measured. Straw incorporation with reduced inorganic fertiliser application ensured a higher shoot dry weight and yield only in flooded clay soil as compared with P0 and P1, and a similar shoot dry weight and yield to P1 under drained clay soil. A positive growth response was facilitated by an increased water-use efficiency and rate of photosynthesis in shoots, and increased root system plasticity through the production of greater root length, more roots in deep soil layers, and an increased fraction of fine roots. Straw enhanced P extractability in soil. Drained soil reduced P uptake (15–45 %) and increased P-use efficiency. In addition to the re-translocation of P from senescing leaves and stems under both moisture conditions, the P concentration in green leaves under drained condition was also reduced (41–72 %). Growth benefits of straw incorporation were observed in clay soil under both moisture conditions, and this was facilitated by the improved P availability, increased P uptake, and greater root system plasticity with the production of deeper and finer roots, compared with that in sandy soil, and inorganic fertiliser applications alone. As P uptake was reduced under drained soil, P re-translocation and % P allocated to panicles increased.

Solanum insanum L. (subgenus Leptostemonum Bitter, Solanaceae), the neglected wild progenitor of eggplant ( S. melongena L.): a review of taxonomy, characteristics and uses aimed at its enhancement for improved eggplant breeding

Abstract: Solanum insanum L. (Solanaceaeae) is the wild progenitor of common eggplant (S. melongena L.) and is naturally distributed in south and southeast Asia, Madagascar and Mauritius. Despite interest in its potential for eggplant breeding it has not been studied extensively. Solanum insanum has been subjected to various taxonomic treatments, with several discussions and arguments on its delimitation as a species, due to its close similarities with the cultivated S. melongena and the wild species S. incanum L. from the Middle East and northern Africa. Solanum insanum has long been used in a variety of medicinal and culinary preparations across many different Asian ethnolinguistic groups. Limited studies carried out on its chemical composition and pharmacognostical properties coupled with ethnobotanic studies reveal that S. insanum has potential for eggplant improvement with respect to phytochemical properties of interest for human health. Further study of morphological and genetic diversity in S. insanum is essential to promote its utilization in eggplant breeding, in light of its potential to hybridize with cultivated eggplant successfully. Here we compile and review the taxonomy, phytogeography, ecology and habitat characteristics, cytology, ethnobotany, breeding and phytochemical analysis of S. insanum. A comprehensive botanical description and illustrations for S. insanum are provided. A detailed comparison of S. insanum and its closely allied species, S. melongena and S. incanum is also made. The potential of S. insanum for crop improvement and future research priorities are discussed.