21 research outputs found

    Lablab purpureus—A Crop Lost for Africa?

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    In recent years, so-called ‘lost crops’ have been appraised in a number of reviews, among them Lablab purpureus in the context of African vegetable species. This crop cannot truly be considered ‘lost’ because worldwide more than 150 common names are applied to it. Based on a comprehensive literature review, this paper aims to put forward four theses, (i) Lablab is one of the most diverse domesticated legume species and has multiple uses. Although its largest agro-morphological diversity occurs in South Asia, its origin appears to be Africa. (ii) Crop improvement in South Asia is based on limited genetic diversity. (iii) The restricted research and development performed in Africa focuses either on improving forage or soil properties mostly through one popular cultivar, Rongai, while the available diversity of lablab in Africa might be under threat of genetic erosion. (iv) Lablab is better adapted to drought than common beans (Phaseolus vulgaris) or cowpea (Vigna unguiculata), both of which have been preferred to lablab in African agricultural production systems. Lablab might offer comparable opportunities for African agriculture in the view of global change. Its wide potential for adaptation throughout eastern and southern Africa is shown with a GIS (geographic information systems) approach

    Simulation of rice brown planthopper [<i style="">Nilaparvata lugens</i> (Stal)] damage for determining economic injury levels

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    338-345This study presents InfoCrop-rice model to simulate damage mechanism of brown planthopper (BPH), Nilaparvata lugens (Stal.) on two rice cultivars (Pusa Basmati 1 and ADT-38). Simulated yield and TDM losses were proximal to respective observed losses of yield (R2 = 0.801; RMSE = 18.47%) and TDM (R2 = 0.843; 20. 73%), indicating proper validation of damage mechanism of BPH. Validated model simulated economic injury levels (EILs) of BPH at different rice growth stages with two control expenditures, incurred on two applications with each of monocrotophos 36 WSC @ 500 g a.i./ha and buprofezin 25 SC @ 100 g a.i./ha and three market prices of Pusa Basmati 1 and ADT-38 apiece. EIL exhibited a negative relationship with market value of produce but had a positive with control measure expenditure

    Assessment of Groundwater Quality in CKDu Affected Areas of Sri Lanka: Implications for Drinking Water Treatment

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    This study investigated the water quality of the groundwater that was collected from the chronic kidney disease of unknown etiology (CKDu) prevailing areas in the dry zone of Sri Lanka to assess its suitability for drinking purposes, and for the first time a Water Quality Index (WQI) with emphasis on proposing appropriate drinking water treatment method was developed. A total of 88 groundwater samples were collected in dry (December 2016) and wet (May 2017) seasons; high concentrations of water hardness, fluoride, salinity, dissolved organic carbon (DOC), and the general alkaline nature of water were the main issues that were observed for disease incidence. The chemical weathering of the underlying bedrock, followed by ion exchange and precipitation processes, primarily controlled groundwater geochemistry. During the 1985&#8211;2017 period, the variations of the annual rainfall and temperature were minimal, which suggests no evidence for major climatic changes within the study areas. Almost all of the samples from the CKDu regions show a low alkali hazard and most of the samples show a medium to high salinity hazard. The DOC of the studied samples was mainly composed of the organic fractions in the following order, as fulvic acids &gt; humic acids &gt; aromatic protein II &gt; soluble microbial by-products, and the molecular weights (MW) of these fractions ranged from 100&#8211;3000 Da. Based on the water quality index (WQI) calculations, it was found that only 3.8% in the wet season and 2.6% in the dry season of total water samples were categorized as the &#8220;excellent&#8222; type, and all other water sources require a further treatment before consumption. As there is an urgent need for establishing proper long-term drinking water treatment technology for the CKDu affected area, these findings can be used as benchmark of raw water quality in the design processes of treatment plants

    Groundwater-Based Drinking Water Supply in Sri Lanka: Status and Perspectives

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    Drinking water is largely from groundwater in Sri Lanka, so quality management is of great concern. In order to achieve the 6th goal of United Nations (UN) Sustainable Development Goals (SDG), more efforts are being undertaken to secure drinking water quality. In this paper, the current status, challenges and opportunities of groundwater quality management and improvement in Sri Lanka were reviewed and discussed, based on previous studies. There are Ca-HCO3 type, Ca–Mg-HCO3 type and Na–SO4–Cl type groundwater dominated in the wet zone, intermediate and the dry zone, respectively. Elevated levels of hardness, fluoride, DOC, and alkalinity, and salinity are reported in the groundwater in the dry zone controlled by geology and arid climate. Although groundwater in some regions contain significant levels of nitrates, arsenic, cadmium and lead, the majority remain at acceptable levels for drinking purposes. As for treatment technologies, existing membrane-based drinking water treatment technologies such as RO (Reverse Osmosis) stations can produce safe and clean drinking water to the community, but this has still a limited coverage. To achieve a safe drinking water supply for all, especially in rural communities of Sri Lanka under the 6th goal of the UN SDG, more efforts in building up the infrastructure and man power are needed to monitor and assess groundwater quality regularly so as to develop management strategies. Research and development can be directed towards more cost-effective water treatment technologies. Protection of groundwater from being polluted, and educational and awareness programs for the stakeholders are also essential tasks in the future

    Ocular surface changes in patients who have undergone head and neck radiation therapy

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    Purpose: Dry eye syndrome (DES) is a familiar sequelae of radiation therapy (RT) for head and neck cancers (HNC). Ocular surface changes such as DES occur due to injury to the conjunctival epithelium, goblet cells, corneal surface, lacrimal glands, and meibomian glands. This study aimed at the evaluation and early detection of changes in ocular surface parameters in patients receiving RT for extraocular HNC. Methods: Forty-two eyes of 21 patients undergoing HNC RT were evaluated. Radiation technique and dose of radiation to the lens and eye were recorded. Subjects were evaluated for meibomian gland changes by meiboscore grading, ocular surface disease index (OSDI) questionnaire, Schirmer’s test, tear film break-up time (TBUT), and slit-lamp examination before RT, immediately post RT, and 6 weeks post RT. A comparison of the ipsilateral eye on the irradiated side to the contralateral eye was done. Results: A significant reduction in TBUT was seen immediately post RT and 6 weeks post RT (P 13 was seen in 23.80% of patients post RT, with a significant difference from baseline (P 1 second in TBUT and >1.7 in meiboscore was seen with a mean dose of around 8 Gy to the lens. Conclusion: All patients undergoing HNC RT should be followed up for ocular surface and meibomian gland changes. The contralateral eye should also be evaluated. Patients receiving lower doses to the ocular structures should also be kept under follow-up

    Spatiotemporal Variation of Groundwater Quality in North Central Province, Sri Lanka

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    This study focused on fulfilling the demand for a comprehensive investigation of groundwater quality in the North Central Province (NCP) of Sri Lanka to achieve United Nations Sustainable Development Goal 6 (Ensure availability and sustainable management of water and sanitation for all). The NCP was selected as the study area due to its highest prevalence of chronic kidney disease with unknown etiology within Sri Lanka. Here, 334 shallow and deep groundwater samples were collected at the end of wet and dry seasons, respectively. Results revealed that elevated and unexpected levels of salinity, hardness, fluoride, nitrate, sulfate, and dissolved organic carbon and the alkaline nature of groundwater were the main issues, and the Ca-HCO3 type was dominant in the groundwater. Water quality index analyses showed that 8.9% and 13.8% of wells had poor quality undrinkable groundwater in wet and dry seasons, respectively. Only 7% of samples were susceptible to sodium and salinity hazards for irrigational use. Reverse osmosis technology with a softening and activated carbon pretreatment process was identified as the most suitable way to treat groundwater with high salinity for many regions of the NCP. The groundwater quality atlas for the NCP created by this study was very useful for making a master plan of safe drinking water supplies and developing and implementing cost-effective water purification technologies in the NCP
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