The agriculture sector in Sri Lanka has been perceived by a large proportion of politicians, poli... more The agriculture sector in Sri Lanka has been perceived by a large proportion of politicians, policy makers, scientists, academia, and general public as a sector with “low productivity”. Yet, once the contribution of food and related industries are added, the Agri-Food Sector (AFS) is highly productive and vibrant, just as much as in any economy. Therefore, the political leadership should be aware of the contributions made by the AFS and be cautious in interpreting the productivity estimates made by various agencies, especially on the productivity of agriculture, forestry and fisheries sector in Sri Lanka. Further, the size of the AFS of Sri Lankan economy and the contributions of overall AFS and the sub-sectors, i.e., agriculture, food manufacturing and food service, should be taken into account if contribution to the Gross Domestic Product and to employment is to be more accurately perceived. Identification of productivity of different sub-sectors together with the constraints to i...
Journal of the National Science Foundation of Sri Lanka, 2021
The study assessed the variations in morphologically, physiologically and anatomically distinct t... more The study assessed the variations in morphologically, physiologically and anatomically distinct traits of wild rice species in Sri Lanka; O. nivara, O. rufipogon, O. eichingeri, O. rhizomatis and O. granulata, which could be useful in rice breeding. The wild rice species were grown in a common garden, and the morphological traits were measured soon after heading. The results showed qualitative parameters such as the panicle type, awning, stigma colour, lemma and palea pubescence, seed coat colour, blade pubescence and ligule shape, are distinctive among the five species and are promising characters in their field identification. ANOVA revealed that the quantitative traits, such as flag leaf length, flag leaf width, culm length, culm diameter, panicle length, 100 grain weight and plant height are useful for further confirmation of species. The highest net photosynthetic rate (5.86 µmol m-2 s-1), high cluster width of the base (61.4 µm), and trichome density (184.33 per 25 mm 2 area) were observed in O. rufipogon compared to the rest, and such desirable traits are effective in rice breeding. Moreover, transpiration rates, stomatal conductance and substomatal CO 2 concentration are ideal physiological traits to be considered in super rice breeding. Significant correlations were observed between transpiration and photosynthesis processes. Thus, our study provides a clear picture on habitat preferences, life cycle, distinctive morphologies and diverse functional traits to be effectively used in field identification and future utilisation of wild relatives of rice in the plant breeding programmes.
Journal of Higher Education Outreach and Engagement, 2019
This study aims to fill in the gap in literature on the state of academic engagement in Sri Lanka... more This study aims to fill in the gap in literature on the state of academic engagement in Sri Lanka by investigating types of outreach engagement activities, outreach mechanisms, and attitudes of academic agriculturalists toward outreach. An online questionnaire survey was conducted among the academics (stratified random sample of 257) across eight faculties of agriculture in the state universities of Sri Lanka. According to the results, the average number of outreach activities per academic per year was 2.9, and the majority spent less than 5% of their working time on outreach activities, indicating low involvement in outreach by the academics. However, they held positive views on outreach engagement. Generally, the academics engaged in outreach activities through personal or informal individual contacts. Findings help provide guidelines for strategies to improve outreach engagement by academics at department, faculty, university, and national levels in Sri Lanka.
Rapid growth of population, diminishing natural resources, climate change, shrinking agricultural... more Rapid growth of population, diminishing natural resources, climate change, shrinking agricultural lands and unstable markets are making the global food systems rather insecure. Therefore, modern agriculture and food systems should be more productive in terms of output, efficient in operation, resilient to climate change and sustainable for the future generations. As a result, the need of a technological transformation is greater than ever before. Being a recent advancement in computer sciences, Artificial Intelligence (AI) has the capacity to address the challenges of this new paradigm. Hence, understanding the importance and applicability of AI in agriculture and food sector could be vital in the journey towards achieving global food security. This review focuses on the AI applications in relation to four pillars of food security (food availability, food accessibility, food utilization and stability) as defined by FAO, in detail. The AI technologies are being applied worldwide in a...
Ability of some rice (Oryza sativa L.) genotypes to germinate and grow under submerged conditions... more Ability of some rice (Oryza sativa L.) genotypes to germinate and grow under submerged conditions where oxygen supply is limited provides an efficient mean for weed control in direct seeded rice. This study was conducted to screen 38 rice varieties to anaerobic germination (AG) tolerance and to identify the influence of hydro-priming on survival and physiological responses of germinated seeds. Seed paddy was sown on saturated soil and soil inundated with 10 cm of stagnant water (submerged) to estimate the survival scores at 21 days after seeding. Six varieties having high survival scores under submerged condition were selected and their seeds were hydro-primed for 24 hrs in the dark at room temperature (25 °C) and were sown in saturated and submerged (10 cm water level) conditions. Soluble sugars, starch and α-amylase of germinating seeds were extracted and a separate set was kept to count the survival score. Varieties including Bg 300, Bg 310 and At 308 had moderate level of tolerance to AG. Hydro-priming improved the survival of rice seeds to about 40%. The synthesis of soluble sugars, starch degradation and α-amylase activity increased by hydro-priming compared to non-primed seeds germinated under submerged condition. Survival rate correlated positively with soluble sugar (r = 0.74) and αamylase (r = 0.79) contents and negatively with starch content (r =-0.51) at p < 0.05. These results emphasized the importance of hydro-priming as a seed treatment to enhance anaerobic germination tolerance in rice.
Cleome rutidosperma is one of the invasive C3 weed species in dry-seeded rice systems in South an... more Cleome rutidosperma is one of the invasive C3 weed species in dry-seeded rice systems in South and Southeast Asia. Cleome species have shown a cytological developmental progression from C3 to C4 photosynthesis. Hence, a better understanding of growth responses of the weed in rice is critical in developing sustainable integrated management approaches for the suppression of this weed. Physiological and morphological changes of C. rutidosperma were studied in a pot experiment by growing the weed alone (1 plant per pot; 0.045 m2) and in competition with 4, 8, 12, and 16 plants per pot of two rice cultivars namely, IR64 and SACG4, in separate pots. The plant height of C. rutidosperma was not affected by the rice density or cultivar, and the height increased linearly with increasing time. The leaf area production of the lower half of the weed was reduced by 80–88% when grown with 12 and 16 rice plants compared to that grown without rice interference. Rice interference at the density of 16 plants per pot reduced leaf biomass of the weed by 92%, inflorescence biomass by 93%, stems biomass by 90%, and root biomass by 92% compared to the weed plants grown alone. The leaf and stem biomass allocation was higher to the lower half of the weed than that to the upper half, when grown in competition with rice. The specific stem length of C. rutidosperma increased by 84% in the presence of 12 rice plants (sowing density 60 kg/ha) compared to 4 plants (sowing density 20 kg/ha), indicating the change in resource allocation to stem elongation to enable the weed to compete effectively under shade to acquire light. However, the relative growth rate of the weed declined by 28% and 54% in the presence of 16 rice plants (sowing density of 80 kg/ha) during 3–5 and 5–7 weeks after sowing, respectively, compared to when the weed was grown without rice interference, reflecting less competitiveness of the weed for the resource acquisition under crop competition. The results of this study showed that the rice interference alone can reduce the weed's growth to a great extent. Therefore, the need of integration of other management practices in dry-seeded rice along with crop interference is highlighted to achieve complete control of C. rutidosperma and similar weeds.
Rice is interwoven with the culture of Sri Lankans. Being the major staple food crop, rice cultiv... more Rice is interwoven with the culture of Sri Lankans. Being the major staple food crop, rice cultivation has maintained its priority status in the agricultural sector of the country. The intensive management practices adopted by the practitioners have resulted in genetic erosion, thus affecting the species composition of the rice field ecosystems in Sri Lanka. This paper presents a review on the work carried out on the biological diversity of lowland rice field ecosystems of Sri Lanka, and proposes the need for conservation strategies to ensure the sustainability of these rice growing ecosystems in the long run.
Changes in the climate have worsen the problems caused by weeds and invasive alien plants (IAPs) ... more Changes in the climate have worsen the problems caused by weeds and invasive alien plants (IAPs) in agro-ecosystems at global scale resulting from their changes in the range and population densities. Over the past six decades, Sri Lanka has experienced a slow but steady increase in annual environmental temperature by 0.01–0.03°C. Increasing extreme events of rainfall, wetter wet seasons, and drier dry seasons are some of the characteristic features of the changes in the climate observed in Sri Lanka over the years. The Ministry of Environment (MOE) in Sri Lanka has established a National Invasive Species Specialist Group (NISSG) in 2012 and adopted the National Policy on Invasive Alien Species (IAS) in Sri Lanka, Strategies and Action Plan in 2016. Further, the MOE has developed and adopted protocols to assess the risk of IAS at pre- and post-entry level to the country while incorporating climate change concerns. Periodic risk assessments have being carried out to prioritize actions...
Farming communities in the hills and mountains of the Himalayan region are some of the most vulne... more Farming communities in the hills and mountains of the Himalayan region are some of the most vulnerable to the changing climate, owing to their specific biophysical and socioeconomic conditions. Understanding the observed parameters of the changing climate and the farmers’ perceptions of it, together with their coping approaches, is an important asset to making farming communities resilient. Therefore, this study aimed to explore the observed change in climatic variables; understand farmers’ perceptions of the changing climate; and document their adaptation approaches in farming systems in the mid-hills of the central Himalayas. Data on the observed change in climatic variables were obtained from the nearby meteorological stations and gridded regional products, and farmers’ perceptions and their adaptation practices were collected from household surveys and from the interviews of key informants. The analysis of temperature data revealed that there has been a clear warming trend. Wint...
Accurate and timely information on the productivity-related spatial characteristics in paddy fiel... more Accurate and timely information on the productivity-related spatial characteristics in paddy fields will facilitate accurate decision-making to achieve food security needs. The aim of the present study was to map rice-cultivating regions in Sri Lanka based on crop productivity and related agronomic decisions made. A grid-based map coupled with a paddy land map of the country was used for the sampling protocol, and the generated data were mapped using ArcGIS software. The study revealed the spatial heterogeneity in the productivity of lowland paddy lands, rice varieties cultivated according to their age classes and breeding stations, water sources used for cultivation, and crops grown in lowlands during the water-limited cropping seasons. The constructed maps carrying the productivity-related spatial characteristics of rice across the country could facilitate agricultural decision support systems. The maps could be used to develop novel approaches for the management of rice productivity in rice-based cropping systems in the country.
ABSTRACT Climate is changing at an alarming rate, imposing significant negative impacts on the qu... more ABSTRACT Climate is changing at an alarming rate, imposing significant negative impacts on the quantity and nutritional quality of the economical crop yield. Overreliance on staple cereals that demand high inputs has ecological, economic, and nutritional risks. Nutritional profiles of major food crops are being degraded under changing climate and the global micronutrient malnutrition called `hidden hunger` causes severe health impacts on developing countries in the world. Elevated atmospheric temperature and CO2 concentration have reduced iron (Fe) and zinc (Zn) levels of major food crops, thus, leading to dietary deficiencies of these micronutrients, constituting a major public health concern. Food legumes, which are highly suitable crops in the low-input farming systems, are a well-known source of Fe and Zn. Further, low-input farming systems have been reported as an integral component in climate-resilient food systems. Efficient use of existing genetic diversity of food legumes could improve the nutritional output of cropping systems, thereby sustaining human Fe and Zn nutrition in the face of global climate change. This review explores and describes the underexploited potentials of food legumes to be used as an integral component in low-input food-production systems adapted to climate change to combat micronutrient malnutrition, particularly focusing on Fe and Zn, which are of significant concern as key drivers of global micronutrient malnutrition.
This study assessed the climate resilience and characterized the existing farming systems in stee... more This study assessed the climate resilience and characterized the existing farming systems in steep terrain in the hilly regions in South Asia. The farming systems considered were at an elevation ≥300 m in the mountain regions of two sites from Sri Lanka (Hatton and Welimada) and one site each from Bangladesh (Chittagong) and Nepal (Jhikhu Khola). A Climate Resilience Index (CRIi) score, varying from 0 (negligible resilience) and 1 (very high resilience), was calculated for each household using 31 parameters under Adaptive Capacity (ADC), Absorptive Capacity (ABC) and Transformative Capacity (TC). To spatially represent the CRIi, the four study locations were mapped using Inverse Distance Weighted (IDW) interpolation technique of GIS. All 424 households in the study sites scored a CRIi between 0.36 and 0.76, while the average CRI was the highest in Hatton (0.67), followed by Welimada (0.60), Jhikhu Khola (0.59) and Chittagong (0.48). Different demographic, socioeconomic and environme...
Weed seedbank was assessed and an integrated weed management package was developed to control Par... more Weed seedbank was assessed and an integrated weed management package was developed to control Parthenium hysterophorus in vegetable capsicum. Field experiments were conducted simultaneously in a Parthenium-site (PS) and Parthenium-free site (PFS) during two consecutive seasons in a split-plot design replicated three times. Primary tillage (ploughing and manual weeding) were the main plots and sub-plots consisted of post-tillage practices; (a) Oxyfluorfen applied two-days before transplanting the crop (180 g a.i. ha −1), (b) gliricidia leaf mulch applied soon after transplanting (6 t ha −1 , 68% moisture), and (c) control. After transplanting, all weeds in PS, except P. hysterophorus, were removed manually in all plots biweekly , while weeds were not controlled in PFS. Parthenium hysterophorus in PS and Cyperus rotundus in PFS dominated the soil seedbank in upper 0-5 cm. Soil seedbank of P. hysterophorus in PS was higher in season-1 (March-August) than in season-2 (September-February) and viable even when buried 15 cm deep. Interaction between primary and post-tillage practices was not significant (P > .05) on plant height, canopy width, and yield of the crop. Capsicum yield in PFS was 40% higher in season-1 and 9.5% higher in season-2 compared to those of PS, due to lower weed competition and higher crop growth in the former. Manual weeding or ploughing as primary tillage followed by mulching with gliricidia leaves as a post-tillage practice suppressed P. hysterophorus effectively and enhanced growth and yield of vegetable capsicum.
Climate change will have adverse effects on global food production. Potential reduction in crop p... more Climate change will have adverse effects on global food production. Potential reduction in crop productivity will be one of the biggest challenges. The objective of this study was to assess the yield fluctuation using Agriculture Production Systems Simulator (APSIM), based on climate change predictions given by the Intergovernmental Panel on Climate Change (IPCC) in 2014. Rice (Oryza sativa L.) yields were simulated with increasing temperature, CO2 concentration and rainfall for three time periods; 2017 (current), 2050 and 2100. The simulations were run for medium (Bg359) and short (Bg300) duration rice varieties for 9 locations representing Wet Zone, Intermediate Zone and Dry Zone and for both Yala (March to September) and Maha (October to February) seasons. Simulation results revealed that the Wet Zone rice yield of Bg300 decreased in Maha season by 18% and 31% and the Dry Zone rice yield of Bg359 decreased in Yala season by 17%, and 42% for 2050 and 2100, respectively. Therefore,...
Agricultural Research for Sustainable Food Systems in Sri Lanka, 2020
Many countries are in the process of transforming their food systems to be more environmentally s... more Many countries are in the process of transforming their food systems to be more environmentally sustainable and resilient and able to deliver healthy and nutritious diets to all. Sri Lanka is no exception to this process. This chapter describes the key features of different subcomponents of food systems of Sri Lanka and presents the opportunities and challenges faced by Sri Lanka in order to make food systems more sustainable. Authors argue that interrelationships among various elements of the food system should be given due consideration in designing and redesigning policies, institutions and technologies to address complex issues governing the food systems of the country.
The agriculture sector in Sri Lanka has been perceived by a large proportion of politicians, poli... more The agriculture sector in Sri Lanka has been perceived by a large proportion of politicians, policy makers, scientists, academia, and general public as a sector with “low productivity”. Yet, once the contribution of food and related industries are added, the Agri-Food Sector (AFS) is highly productive and vibrant, just as much as in any economy. Therefore, the political leadership should be aware of the contributions made by the AFS and be cautious in interpreting the productivity estimates made by various agencies, especially on the productivity of agriculture, forestry and fisheries sector in Sri Lanka. Further, the size of the AFS of Sri Lankan economy and the contributions of overall AFS and the sub-sectors, i.e., agriculture, food manufacturing and food service, should be taken into account if contribution to the Gross Domestic Product and to employment is to be more accurately perceived. Identification of productivity of different sub-sectors together with the constraints to i...
Journal of the National Science Foundation of Sri Lanka, 2021
The study assessed the variations in morphologically, physiologically and anatomically distinct t... more The study assessed the variations in morphologically, physiologically and anatomically distinct traits of wild rice species in Sri Lanka; O. nivara, O. rufipogon, O. eichingeri, O. rhizomatis and O. granulata, which could be useful in rice breeding. The wild rice species were grown in a common garden, and the morphological traits were measured soon after heading. The results showed qualitative parameters such as the panicle type, awning, stigma colour, lemma and palea pubescence, seed coat colour, blade pubescence and ligule shape, are distinctive among the five species and are promising characters in their field identification. ANOVA revealed that the quantitative traits, such as flag leaf length, flag leaf width, culm length, culm diameter, panicle length, 100 grain weight and plant height are useful for further confirmation of species. The highest net photosynthetic rate (5.86 µmol m-2 s-1), high cluster width of the base (61.4 µm), and trichome density (184.33 per 25 mm 2 area) were observed in O. rufipogon compared to the rest, and such desirable traits are effective in rice breeding. Moreover, transpiration rates, stomatal conductance and substomatal CO 2 concentration are ideal physiological traits to be considered in super rice breeding. Significant correlations were observed between transpiration and photosynthesis processes. Thus, our study provides a clear picture on habitat preferences, life cycle, distinctive morphologies and diverse functional traits to be effectively used in field identification and future utilisation of wild relatives of rice in the plant breeding programmes.
Journal of Higher Education Outreach and Engagement, 2019
This study aims to fill in the gap in literature on the state of academic engagement in Sri Lanka... more This study aims to fill in the gap in literature on the state of academic engagement in Sri Lanka by investigating types of outreach engagement activities, outreach mechanisms, and attitudes of academic agriculturalists toward outreach. An online questionnaire survey was conducted among the academics (stratified random sample of 257) across eight faculties of agriculture in the state universities of Sri Lanka. According to the results, the average number of outreach activities per academic per year was 2.9, and the majority spent less than 5% of their working time on outreach activities, indicating low involvement in outreach by the academics. However, they held positive views on outreach engagement. Generally, the academics engaged in outreach activities through personal or informal individual contacts. Findings help provide guidelines for strategies to improve outreach engagement by academics at department, faculty, university, and national levels in Sri Lanka.
Rapid growth of population, diminishing natural resources, climate change, shrinking agricultural... more Rapid growth of population, diminishing natural resources, climate change, shrinking agricultural lands and unstable markets are making the global food systems rather insecure. Therefore, modern agriculture and food systems should be more productive in terms of output, efficient in operation, resilient to climate change and sustainable for the future generations. As a result, the need of a technological transformation is greater than ever before. Being a recent advancement in computer sciences, Artificial Intelligence (AI) has the capacity to address the challenges of this new paradigm. Hence, understanding the importance and applicability of AI in agriculture and food sector could be vital in the journey towards achieving global food security. This review focuses on the AI applications in relation to four pillars of food security (food availability, food accessibility, food utilization and stability) as defined by FAO, in detail. The AI technologies are being applied worldwide in a...
Ability of some rice (Oryza sativa L.) genotypes to germinate and grow under submerged conditions... more Ability of some rice (Oryza sativa L.) genotypes to germinate and grow under submerged conditions where oxygen supply is limited provides an efficient mean for weed control in direct seeded rice. This study was conducted to screen 38 rice varieties to anaerobic germination (AG) tolerance and to identify the influence of hydro-priming on survival and physiological responses of germinated seeds. Seed paddy was sown on saturated soil and soil inundated with 10 cm of stagnant water (submerged) to estimate the survival scores at 21 days after seeding. Six varieties having high survival scores under submerged condition were selected and their seeds were hydro-primed for 24 hrs in the dark at room temperature (25 °C) and were sown in saturated and submerged (10 cm water level) conditions. Soluble sugars, starch and α-amylase of germinating seeds were extracted and a separate set was kept to count the survival score. Varieties including Bg 300, Bg 310 and At 308 had moderate level of tolerance to AG. Hydro-priming improved the survival of rice seeds to about 40%. The synthesis of soluble sugars, starch degradation and α-amylase activity increased by hydro-priming compared to non-primed seeds germinated under submerged condition. Survival rate correlated positively with soluble sugar (r = 0.74) and αamylase (r = 0.79) contents and negatively with starch content (r =-0.51) at p < 0.05. These results emphasized the importance of hydro-priming as a seed treatment to enhance anaerobic germination tolerance in rice.
Cleome rutidosperma is one of the invasive C3 weed species in dry-seeded rice systems in South an... more Cleome rutidosperma is one of the invasive C3 weed species in dry-seeded rice systems in South and Southeast Asia. Cleome species have shown a cytological developmental progression from C3 to C4 photosynthesis. Hence, a better understanding of growth responses of the weed in rice is critical in developing sustainable integrated management approaches for the suppression of this weed. Physiological and morphological changes of C. rutidosperma were studied in a pot experiment by growing the weed alone (1 plant per pot; 0.045 m2) and in competition with 4, 8, 12, and 16 plants per pot of two rice cultivars namely, IR64 and SACG4, in separate pots. The plant height of C. rutidosperma was not affected by the rice density or cultivar, and the height increased linearly with increasing time. The leaf area production of the lower half of the weed was reduced by 80–88% when grown with 12 and 16 rice plants compared to that grown without rice interference. Rice interference at the density of 16 plants per pot reduced leaf biomass of the weed by 92%, inflorescence biomass by 93%, stems biomass by 90%, and root biomass by 92% compared to the weed plants grown alone. The leaf and stem biomass allocation was higher to the lower half of the weed than that to the upper half, when grown in competition with rice. The specific stem length of C. rutidosperma increased by 84% in the presence of 12 rice plants (sowing density 60 kg/ha) compared to 4 plants (sowing density 20 kg/ha), indicating the change in resource allocation to stem elongation to enable the weed to compete effectively under shade to acquire light. However, the relative growth rate of the weed declined by 28% and 54% in the presence of 16 rice plants (sowing density of 80 kg/ha) during 3–5 and 5–7 weeks after sowing, respectively, compared to when the weed was grown without rice interference, reflecting less competitiveness of the weed for the resource acquisition under crop competition. The results of this study showed that the rice interference alone can reduce the weed's growth to a great extent. Therefore, the need of integration of other management practices in dry-seeded rice along with crop interference is highlighted to achieve complete control of C. rutidosperma and similar weeds.
Rice is interwoven with the culture of Sri Lankans. Being the major staple food crop, rice cultiv... more Rice is interwoven with the culture of Sri Lankans. Being the major staple food crop, rice cultivation has maintained its priority status in the agricultural sector of the country. The intensive management practices adopted by the practitioners have resulted in genetic erosion, thus affecting the species composition of the rice field ecosystems in Sri Lanka. This paper presents a review on the work carried out on the biological diversity of lowland rice field ecosystems of Sri Lanka, and proposes the need for conservation strategies to ensure the sustainability of these rice growing ecosystems in the long run.
Changes in the climate have worsen the problems caused by weeds and invasive alien plants (IAPs) ... more Changes in the climate have worsen the problems caused by weeds and invasive alien plants (IAPs) in agro-ecosystems at global scale resulting from their changes in the range and population densities. Over the past six decades, Sri Lanka has experienced a slow but steady increase in annual environmental temperature by 0.01–0.03°C. Increasing extreme events of rainfall, wetter wet seasons, and drier dry seasons are some of the characteristic features of the changes in the climate observed in Sri Lanka over the years. The Ministry of Environment (MOE) in Sri Lanka has established a National Invasive Species Specialist Group (NISSG) in 2012 and adopted the National Policy on Invasive Alien Species (IAS) in Sri Lanka, Strategies and Action Plan in 2016. Further, the MOE has developed and adopted protocols to assess the risk of IAS at pre- and post-entry level to the country while incorporating climate change concerns. Periodic risk assessments have being carried out to prioritize actions...
Farming communities in the hills and mountains of the Himalayan region are some of the most vulne... more Farming communities in the hills and mountains of the Himalayan region are some of the most vulnerable to the changing climate, owing to their specific biophysical and socioeconomic conditions. Understanding the observed parameters of the changing climate and the farmers’ perceptions of it, together with their coping approaches, is an important asset to making farming communities resilient. Therefore, this study aimed to explore the observed change in climatic variables; understand farmers’ perceptions of the changing climate; and document their adaptation approaches in farming systems in the mid-hills of the central Himalayas. Data on the observed change in climatic variables were obtained from the nearby meteorological stations and gridded regional products, and farmers’ perceptions and their adaptation practices were collected from household surveys and from the interviews of key informants. The analysis of temperature data revealed that there has been a clear warming trend. Wint...
Accurate and timely information on the productivity-related spatial characteristics in paddy fiel... more Accurate and timely information on the productivity-related spatial characteristics in paddy fields will facilitate accurate decision-making to achieve food security needs. The aim of the present study was to map rice-cultivating regions in Sri Lanka based on crop productivity and related agronomic decisions made. A grid-based map coupled with a paddy land map of the country was used for the sampling protocol, and the generated data were mapped using ArcGIS software. The study revealed the spatial heterogeneity in the productivity of lowland paddy lands, rice varieties cultivated according to their age classes and breeding stations, water sources used for cultivation, and crops grown in lowlands during the water-limited cropping seasons. The constructed maps carrying the productivity-related spatial characteristics of rice across the country could facilitate agricultural decision support systems. The maps could be used to develop novel approaches for the management of rice productivity in rice-based cropping systems in the country.
ABSTRACT Climate is changing at an alarming rate, imposing significant negative impacts on the qu... more ABSTRACT Climate is changing at an alarming rate, imposing significant negative impacts on the quantity and nutritional quality of the economical crop yield. Overreliance on staple cereals that demand high inputs has ecological, economic, and nutritional risks. Nutritional profiles of major food crops are being degraded under changing climate and the global micronutrient malnutrition called `hidden hunger` causes severe health impacts on developing countries in the world. Elevated atmospheric temperature and CO2 concentration have reduced iron (Fe) and zinc (Zn) levels of major food crops, thus, leading to dietary deficiencies of these micronutrients, constituting a major public health concern. Food legumes, which are highly suitable crops in the low-input farming systems, are a well-known source of Fe and Zn. Further, low-input farming systems have been reported as an integral component in climate-resilient food systems. Efficient use of existing genetic diversity of food legumes could improve the nutritional output of cropping systems, thereby sustaining human Fe and Zn nutrition in the face of global climate change. This review explores and describes the underexploited potentials of food legumes to be used as an integral component in low-input food-production systems adapted to climate change to combat micronutrient malnutrition, particularly focusing on Fe and Zn, which are of significant concern as key drivers of global micronutrient malnutrition.
This study assessed the climate resilience and characterized the existing farming systems in stee... more This study assessed the climate resilience and characterized the existing farming systems in steep terrain in the hilly regions in South Asia. The farming systems considered were at an elevation ≥300 m in the mountain regions of two sites from Sri Lanka (Hatton and Welimada) and one site each from Bangladesh (Chittagong) and Nepal (Jhikhu Khola). A Climate Resilience Index (CRIi) score, varying from 0 (negligible resilience) and 1 (very high resilience), was calculated for each household using 31 parameters under Adaptive Capacity (ADC), Absorptive Capacity (ABC) and Transformative Capacity (TC). To spatially represent the CRIi, the four study locations were mapped using Inverse Distance Weighted (IDW) interpolation technique of GIS. All 424 households in the study sites scored a CRIi between 0.36 and 0.76, while the average CRI was the highest in Hatton (0.67), followed by Welimada (0.60), Jhikhu Khola (0.59) and Chittagong (0.48). Different demographic, socioeconomic and environme...
Weed seedbank was assessed and an integrated weed management package was developed to control Par... more Weed seedbank was assessed and an integrated weed management package was developed to control Parthenium hysterophorus in vegetable capsicum. Field experiments were conducted simultaneously in a Parthenium-site (PS) and Parthenium-free site (PFS) during two consecutive seasons in a split-plot design replicated three times. Primary tillage (ploughing and manual weeding) were the main plots and sub-plots consisted of post-tillage practices; (a) Oxyfluorfen applied two-days before transplanting the crop (180 g a.i. ha −1), (b) gliricidia leaf mulch applied soon after transplanting (6 t ha −1 , 68% moisture), and (c) control. After transplanting, all weeds in PS, except P. hysterophorus, were removed manually in all plots biweekly , while weeds were not controlled in PFS. Parthenium hysterophorus in PS and Cyperus rotundus in PFS dominated the soil seedbank in upper 0-5 cm. Soil seedbank of P. hysterophorus in PS was higher in season-1 (March-August) than in season-2 (September-February) and viable even when buried 15 cm deep. Interaction between primary and post-tillage practices was not significant (P > .05) on plant height, canopy width, and yield of the crop. Capsicum yield in PFS was 40% higher in season-1 and 9.5% higher in season-2 compared to those of PS, due to lower weed competition and higher crop growth in the former. Manual weeding or ploughing as primary tillage followed by mulching with gliricidia leaves as a post-tillage practice suppressed P. hysterophorus effectively and enhanced growth and yield of vegetable capsicum.
Climate change will have adverse effects on global food production. Potential reduction in crop p... more Climate change will have adverse effects on global food production. Potential reduction in crop productivity will be one of the biggest challenges. The objective of this study was to assess the yield fluctuation using Agriculture Production Systems Simulator (APSIM), based on climate change predictions given by the Intergovernmental Panel on Climate Change (IPCC) in 2014. Rice (Oryza sativa L.) yields were simulated with increasing temperature, CO2 concentration and rainfall for three time periods; 2017 (current), 2050 and 2100. The simulations were run for medium (Bg359) and short (Bg300) duration rice varieties for 9 locations representing Wet Zone, Intermediate Zone and Dry Zone and for both Yala (March to September) and Maha (October to February) seasons. Simulation results revealed that the Wet Zone rice yield of Bg300 decreased in Maha season by 18% and 31% and the Dry Zone rice yield of Bg359 decreased in Yala season by 17%, and 42% for 2050 and 2100, respectively. Therefore,...
Agricultural Research for Sustainable Food Systems in Sri Lanka, 2020
Many countries are in the process of transforming their food systems to be more environmentally s... more Many countries are in the process of transforming their food systems to be more environmentally sustainable and resilient and able to deliver healthy and nutritious diets to all. Sri Lanka is no exception to this process. This chapter describes the key features of different subcomponents of food systems of Sri Lanka and presents the opportunities and challenges faced by Sri Lanka in order to make food systems more sustainable. Authors argue that interrelationships among various elements of the food system should be given due consideration in designing and redesigning policies, institutions and technologies to address complex issues governing the food systems of the country.
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Papers by Buddhi Marambe