Cambodian Rice Research Articles

Financial landscapes of agrarian change in Cambodia

In the context of neoliberal financialization, what is the role of debt in agrarian change? To address this question, I combine insights about debt from rural political ecology and development finance scholarship in order to analyze the relationship between changing agroecological practices and household indebtedness in a Cambodian rice- farming village. In the past two decades, Cambodians have borrowed from commercial microfinance institutions at the highest rate per capita of any country in the world. With fewer Cambodians farming, and agricultural production increasingly commodified, researchers have begun to study how the fast growth of Cambodia's microfinance industry contributes to these changes. By building upon the concept of financial landscapes, which highlights the diversity of social and material relations of debt in rural economies, I argue that agrarian change in Cambodia is entangled with rising household debts used to fund both agricultural production and social reproduction. I describe how non-monetary debt obligations underpinned labor-intensive rice agricultural practices in the 1980s and early 1990s, but have since been replaced by monetary debt used to fund household basic needs and commodified agricultural production. To make my argument, I draw upon 20 months of ethnographic research within a farming village in Kampot Province. This article contributes to rural political ecology and development finance scholarship by exploring debt in its diverse material and social forms at a time of deepening financialization, and how these debt relations in turn shape the economic and agroecological contours of contemporary agrarian change.

Cooking and Eating Qualities of <i>Phka Rumduol</i>, A Leading Variety of Cambodian Rice

Cooking and Eating Qualities of <i>Phka Rumduol</i>, A Leading Variety of Cambodian Rice

Factors Influencing Cambodian Rice Exports: An Application of the Dynamic Panel Gravity Model

ABSTRACT This study aims to identify the major factors influencing the Cambodian rice exports through an application of the dynamic gravity framework estimated by the Generalized Least Square (GLS), the Poisson Pseudo-Maximum-Likelihood (PPML), and the Heckman Sample Selection models, based on a period of 22-year panel data (1995–2016) and a total of 40 selected importing partners. The results show that the historical ties, the policy of exchange rate and the agricultural land reform promote the rice exports; the expansion of the exports to the trading partners, especially the EU, China and the ASEAN countries are particularly highlighted. As a macroeconomic issue and resistance factor, the economic recession, impeding the exports flows, would require further special attentions.

Potential yield and nutrient requirements of direct-seeded, dry-season rice in Cambodia

AbstractThe area of dry-season rice (Oryza sativa L.) has rapidly increased in Cambodia owing to the large-scale development of irrigation infrastructure. But little is known of potential productivity and adaptive crop management. The objective of our study was to evaluate potential yield and nutrient requirements of dry-season rice in Cambodia, and the economic feasibility of soil-specific management recommended by the government. Field experiments were conducted on four soil types (Bakan, equivalent to Alfisol; Krakor, Inceptisol; Prateah Lang, Plinthustalfs; and Toul Samroung, Endoaqualfs) in four provinces (Battambang, Kampong Thom, Pursat, and Siem Reap) during the 2016 and 2017 dry seasons to compare 14 (2016) and 8 (2017) N-P-K combinations. Grain yield ranged from 1.0 to 5.5 t ha−1 in 2016 and from 1.3 to 6.7 t ha−1 in 2017. Potential yield from the experiments was 6–7 t ha−1 on Toul Samroung soil, 5–6 t ha−1 on Bakan soil, and 3–5 t ha−1 on Prateah Lang and Krakor soils. A rate of 140-60-60 kg ha−1 of N-P2O5-K2O was more than enough to achieve the best yields on any soil group. On the other hand, modest application rates in soil-specific management (44–78 kg ha−1 of N, 23–28 kg ha−1 of P2O5, 0–30 kg ha−1 of K2O) proved reasonable for resource-poor farmers in Cambodia, since the treatment always provided >75 % of the highest economic profit in high-input plots.

Total phenolic content and antioxidant activity of rice wine from waxy pigmented and non-pigmented rice varieties produced by traditional and multi-parallel fermentation

The study determined the total phenolic (TP) content, antioxidant activity (AOA) and copper reduction antioxidant capacity (CUPRAC) of rice wine from waxy pigmented and non-pigmented rice varieties using traditional and multi-parallel fermentation methods with different starter cultures. The rice wine produced using waxy pigmented rice had high TP and AOA compared to rice wine produced using waxy non-pigmented rice regardless of the method of fermentation (traditional or multi-parallel). The type of starter culture had less effect on the TP, AOA and CUPRAC of the rice wines. The results of the study revealed that the rice wine produced using the Cambodian waxy rice possess bioactive compounds that could function as antioxidants, with higher values obtained from pigmented than the non-pigmented variety. Hence, this study proved that rice wine is a healthy alcoholic drink. However, future research should be conducted to identify the specific antioxidant compounds in rice wine using waxy pigmented rice.

Importance of phosphorus and potassium in soil-specific nutrient management for wet-season rice in Cambodia

AbstractRice is widely grown in rainfed lowlands during the wet season in the Mekong region. Limited nutrient availability is a common constraint on crop yield, and the optimal rate of fertilizer application depends on the soil type. The objective of our study was to evaluate rice productivity and the economic feasibility of various nutrient management regimes in Cambodia. We conducted field experiments on three soil types (Prey Khmer, Prateah Lang, and Toul Samroung, equivalent to Psamments, Plinthustalfs, and Endoaqualfs, respectively) in four provinces (Battambang, Kampong Thom, Pursat, and Siem Reap) during the 2016 and 2017 wet seasons to compare nine (2016) and seven (2017) N–P–K combinations. Grain yield ranged from 0.9 to 4.8 t ha−1 in 2016 and from 1.0 to 5.2 t ha−1 in 2017, depending on soil type and nutrient management. The Prey Khmer soil contained around 80% sand, and rice yield responded most weakly to nutrient management. The moderate fertilizer input in the current soil-specific recommendation was effective on this soil type. However, on more fertile soils with a higher clay content and a higher cation-exchange capacity (Toul Samroung and Prateah Lang), an additional 20 kg N ha−1 combined with adding 15 kg ha−1 of P2O5 or 20 kg ha−1 of K2O significantly increased yield and economic return. Although P and K use during Cambodia’s wet season is uncommon, our results demonstrate the importance of these nutrients in improving the country’s rice production.

Engineering Synthetic Microbial Communities through a Selective Biofilm Cultivation Device for the Production of Fermented Beverages.

Production of Cambodian rice wine involves complex microbial consortia. Indeed, previous studies focused on traditional microbial starters used for this product revealed that three microbial strains with complementary metabolic activities are required for an effective fermentation, i.e., filamentous fungi (Rhizopus oryzae), yeast (Saccharomyces cerevisiae), and lactic acid bacteria (Lactobacillus plantarum). Modulating the ratio between these three key players led to significant differences, not only in terms of ethanol and organic acid production, but also on the profile of volatile compounds, in comparison with natural communities. However, we observed that using an equal ratio of spores/cells of the three microbial strains during inoculation led to flavor profile and ethanol yield close to that obtained through the use of natural communities. Compartmentalization of metabolic tasks through the use of a biofilm cultivation device allows further improvement of the whole fermentation process, notably by increasing the amount of key components of the aroma profile of the fermented beverage (i.e., mainly phenylethyl alcohol, isobutyl alcohol, isoamyl alcohol, and 2-methyl-butanol) and reducing the amount of off-flavor compounds. This study is a step forward in our understanding of interkingdom microbial interactions with strong application potential in food biotechnology.

Mapping quantitative traits for grain physical and textural quality in Cambodian Jasmine rice PRD

Grain physical and textural traits are key parameters that are assessed in rice quality improvement programs. In order to dissect the genetic basis of the premium Cambodian quality rice Phka Rumduol (PRD), a population including more than 300 recombinant inbred lines derived from PRD and Thmar Krem was used to map quantitative trait loci (QTLs) for grain length (GL), grain width (GW), degree of chalkiness, grain translucency and texture-associated traits including amylose content (AC), gelatinisation temperature (GT), gel consistency and pasting properties derived from a rapid visco analyser. QTL analysis revealed large-effect QTLs and minor QTLs for these traits of quality, indicating a complex interplay between major and minor genes. The QTL located on chromosome 3 is the major locus for GL, and the one on chromosome 5 plays a major role in determining GW. A novel QTL for GL was identified on the short arm of chromosome 6 and explained about 20% of the phenotypic variation in GL. Grain translucency and chalkiness were largely controlled by QTLs on chromosome 5 and 6. Putative genes for texture-associated traits relate back to the starch biosynthesis pathways. Major QTLs for AC and GT colocalised to the Waxy and starch synthase IIa genes on chromosome 6, respectively. Minor QTLs on chromosomes 3 and 8 were identified for AC, setback, peak viscosity and hot-paste consistency, and on chromosomes 4 and 7 for GT and pasting temperature. This is the first QTL mapping study for the quality of Cambodian rice.

Environmental and Health Implications of the Correlation Between Arsenic and Zinc Levels in Rice from an Arsenic-Rich Zone in Cambodia.

Background.In parts of Cambodia, irrigation of rice with groundwater results in arsenic accumulation in soils and rice, leading to health concerns associated with rice consumption. In Bangladesh and China, low zinc levels in rice have been found in regions where arsenic levels in rice are high. Furthermore, there have been claims that zinc deficiency is responsible for stunting of children in Cambodia. There are limited data on zinc in Cambodian rice, but in rural Asia, rice is the major source of zinc.Objectives.To provide a preliminary evaluation of the zinc content in rice grain in Preak Russey, an area with elevated levels of arsenic. The importance of zinc in rice for infants was also assessed.Methods.Rice cultivation was evaluated in sixty farms along the Mekong River in Cambodia. Analyses for metals, total arsenic, and arsenic species in the water and rice were conducted at the University of Ottawa, Canada by inductively coupled plasma – mass spectrometry. Analysis of total zinc and arsenic in soils were analyzed in Phnom Penh using X-ray fluorescence spectrometry (XRF). Total zinc in rice was also measured by XRF analysis.Results.Rice in the Preak Russey area contained zinc with ½ to ¼ of the 1987 Codex standard for rice in Infant Formula. Moreover, our average zinc concentration in rice samples was less than a third that recommended for zinc fortification in rice by the United Nations World Food Programme. There was a significant (α=0.05) negative correlation between the arsenic and zinc content of rice with the lowest zinc levels occurring near the irrigation wells, the source of arsenic. There was a significantly higher content of zinc in rice from farms that fertilized with cow manure.Conclusions.Handheld XRF spectrometers are useful tools for detection of zinc levels in rice. The potential for zinc deficiency in farmers in areas of Cambodia with arsenic toxicity is high.Competing Interests.The authors declare no competing financial interests.

How do stakeholder interactions in Cambodian rice farming villages contribute to a pesticide lock-in?

This paper addresses the conditions and mechanisms that sustain pesticide use by Cambodian rice farmers and constrain a transition to more sustainable pest control practices. We analyzed data from a survey of individual farmers (N = 320), focus group discussions with farmer groups, and interviews with input sellers, rat hunters and local extension agents.Our findings show that farmers mix different types (e.g. herbicides and insecticides) and brands of pesticides in one application. Other chemicals, in particular ‘growth activators’ are often added to these mixes. The interaction patterns and financial arrangements among farmers, pesticide sellers, and laborers promote or sustain these practices. Increasing returns to information and recursive social interaction at the community level thus create a lock-in situation for pesticide use.These findings have direct implications on targeting interventions, which are often aimed at providing knowledge to government extension agents and farmers. Our results suggest that farmers’ knowledge on pest management is not the only driver for their decisions and practices. A broader scope of intervention in communication and feedback loops between stakeholders directly interacting with farmers can help to diversify the suite of recommendations while providing a balance in the information that reaches farmers. Changes in these social arrangements and informal rules may be required to affect positive changes in rice pest management.

종류별 쌀 분말을 첨가한 식빵의 제빵 특성

The properties of dough containing added powders of different rice varieties and the bread baking characteristics, based on product preservation evaluation, were compared with those of the control (without added rice). The stability of the dough generally decreased for all the cultivars except for Cambodian rice. Upon addition of 30% of each rice variety, there was no significant difference in terms of volume between the control and the finished product with added rice. The moisture activity of the rice varieties ranged from 0.944 to 0.946, and no significant difference was observed in the water activity. However, the product preservation evaluation indicated that the color and puffiness of the breads with added rice varieties were high. According to the overall preservation evaluation, the softness, taste, and moistness of the breads with added rice in the order: glutinous rice, steamed rice, goami rice, rice, and Cambodian rice. Therefore, in the production of breads containing 30% of rice varieties, the volume and texture of the breads were similar to those of the control, and the elasticity of the products did not decrease even after the storage period of each product. Therefore, we think that it is best to keep the shelf-life of the product.

Groundwater Irrigation and Arsenic Speciation in Rice in Cambodia.

Background.Arsenic bioaccumulation in rice is a global concern affecting food security and public health.Objective.The present study examined arsenic species in rice in Cambodia to characterize health risks with rice consumption and to clarify uncertainties with Codex guidelines.Methods.The present study collected 61 well water samples, 105 rice samples, 70 soil samples, and conducted interviews with 44 families in Preak Russey near the Bassac River and Kandal Province along the Mekong River in Cambodia. Analyses of metals, total arsenic and arsenic species were conducted in laboratories in Canada, Cambodia and Singapore.Results.Unlike in Bangladesh, rice with the highest total arsenic concentrations in Cambodia contains mostly organic arsenic, dimethylarsinic acid (DMA), which is unregulated and much less toxic than inorganic arsenic. The present study found that storing surface runoff in ditches prior to irrigation can significantly reduce the arsenic concentration in rice. It is possible to remove > 95% of arsenic from groundwater prior to irrigation with natural reactions.Conclusions.The provision of high quality drinking water in 2015 to Preak Russey removed about 95% of the dietary inorganic arsenic exposure. The extremes in arsenic toxicity that are still obvious in these farmers should become less common. Rice from the site with the highest documented levels of arsenic in soils and water in Cambodia passes current Codex guidelines for arsenic.Informed Consent.ObtainedCompeting Interests.The authors declare no competing financial interests.

Effects of Arsenic, Iron and Fertilizers in Soil on Rice in Cambodia.

Background.In parts of Cambodia, irrigation with groundwater results in arsenic accumulation in soils and rice, leading to health concerns associated with rice consumption. A high concentration of iron in groundwater can precipitate arsenic and reduce its bioavailability, however high concentrations of arsenic and iron can also reduce rice production. Furthermore, concerns have been raised about chemical contamination from inorganic fertilizers used to grow rice. The relationship between soil geochemistry and arsenic concentrations in rice is not yet fully understood.Objectives.The primary objective of this project was to investigate the relationship between arsenic concentrations in irrigation water, soil and rice collected from different sites in Cambodia. A secondary objective was to explore arsenic and phosphorus levels in fertilizer samples obtained from the study area in Cambodia.Methods.The present study collected 61 well water samples, 105 rice samples, 70 soil samples, 11 inorganic fertilizer samples and conducted interviews with 44 families along the Mekong River in Cambodia. Analyses for metals, total arsenic, and arsenic species in the water and rice were conducted in Canada by inductively coupled plasma mass spectrometry. Analyses for metals, total arsenic and phosphorus in soils and inorganic fertilizers were conducted in Cambodia and Singapore by X-ray fluorescence.Results.The concentration of arsenic in rice paddy soils was highly variable and as much as 20 times higher near the irrigation wells than in more distal areas of the paddy. Two farmers in Preak Russey had integrated soil samples with arsenic levels above the concentration associated with toxicity to rice in Taiwan (40 mg/kg) and above the Dutch concentration requiring intervention or remediation (55 mg/kg). The highest total arsenic measured in soil was 95 mg/kg. In Preak Russey, the loading of arsenic from irrigation water was 3710 times greater than the loading of arsenic from inorganic fertilizers. Half of the commercial inorganic fertilizers had less than 50% of the labelled content of phosphorus.Conclusions.Emphasis should be placed on improving the management of irrigation water, not on inactivation of arsenic in soil. The high levels of iron in groundwater mitigate arsenic toxicity, but the accumulation of iron could later result in lower rice productivity. Irrigation of rice with groundwater is not likely sustainable. To improve rice productivity, the content of phosphorus in local inorganic fertilizers must be improved to world standards. X-ray fluorescence analysis can quickly identify poor quality fertilizers.Informed Consent. ObtainedCompeting Interests.The authors declare no competing financial interests

Impact of access to capital and abiotic stress on production efficiency: Evidence from rice farming in Cambodia

Cambodia is one of the climatic stress-prone countries in Southeast Asia. Rice is the dominant cash crop for Cambodians, and is adversely affected by recurrent droughts and floods. In addition, farmers have limited or no access to capital markets. This article investigates the impact of abiotic stresses (droughts and floods) and access to capital on the farming efficiency of smallholders in Cambodia. We find that the mean technical efficiency of rice farmers is about 0.60, implying that farmers can increase their production by about 40% with existing resources. Drought and soil fertility were identified as the major sources of inefficiency in rice production. Adoption of drought-tolerant varieties could help increase output and efficiency. We also find that access to capital and educational attainment significantly improved rice farming efficiency. Finally, we conclude that increasing rice productivity can help in improving income and thereby reducing poverty among Cambodian rice producers.

The Technological Trajectory of Integrated Pest Management for Rice in Cambodia

For the past two decades, while the efficacy of Integrated Pest Management (IPM) has been successfully demonstrated in Cambodia, its dissemination and sustained adoption among farmers have not met similar success. This study moves away from simplistic analyses about constraints in extension methods for IPM. Instead, we take a broader look into technological systems and the trajectory for pest management, which affected the spread and uptake of IPM in the country. Through a review of the wider context in policies and programs, and a survey of farmers from five provinces in Cambodia (N = 400), we examined the connections between options for pest management at the farmer level and conditions in the technological system. Using the Cambodian case study, we show that the technological system predisposes to pesticide use and as such hinders a trajectory of IPM. Systemic conditions, including interrelated agronomic practices, ecological conditions in farming communities, governance mechanisms, structures around the spread of knowledge and the industry around the technological options, have created mutual socio-technical dependencies. Although programs targeted change through knowledge of IPM, much of the systemic conditions sustain the trajectory of pesticide reliance. Hence, promoting an innovation environment that is supportive of IPM requires extension beyond knowledge dissemination, addressing these varied elements of the technological system.

Effects of climate variability on freshwater fisheries in Cambodia's rice field fisheries: a longitudinal cohort study

BackgroundProjections suggest that by 2050, climate change will reduce global fish catch by 3–13%, with fish catch falling by as much as 30% in some tropical marine systems. Freshwater fisheries are particularly susceptible to the warming effects of climate change because shallower, hydrologically distinct water bodies are easily affected by atmospheric temperatures and less easily accommodate fish migrations. Damage to freshwater fisheries is a problem particularly for poor and undernourished human populations, which are especially dependent on them. Despite the severity of projected climate change effects on fish catch and the risk to human health, few empirical studies have examined how fish catch is already responding to climate variability, the ways fishers are adapting to these changes, and how it affects people's consumption of fish, which are rich in micronutrients and fatty acids. We aim here to account for behavioural responses among fishers to identify the ecological effect of flood and weather on fish catch in Cambodian rice field fisheries, and patterns of fish consumption and nutrition in the local communities. MethodsIn this longitudinal cohort study, we use a panel dataset collected by WorldFish of 400 households dependent on rice field fisheries over 3 years (19 distinct timepoints) to examine how changing flood patterns and temperature alter households' fish catch and whether fishing families respond by either adapting the effort put into fishing (ie, hours, time of day, or number of family members involved) or fish consumption. We analyse the net effect of biophysical changes on household fish catch, the effect of biophysical changes (flood, temperature, and rainfall) on household fish catch and fish consumption with the addition of controls for fishing effort, a key way that fishers might adapt to ecological changes, and the direct effect of biophysical changes on fishing effort and fish consumption. FindingsPreliminary results suggest that from November, 2012, to November, 2015, fishing families changed their fishing effort and practices to adapt to the effects of flood and temperature changes on fish catch. Updated data and analyses will allow us to disentangle these effects by using an identification strategy to separate the ecological effects of flood and temperature changes on fish catch from the ways households respond to changes in fish availability. InterpretationOur results have broad implications for understanding the ways that climate change might affect the 10% of the global population that rely on small-scale fisheries in low-income countries. Analyses of fish catch will show the effects of flood and temperature changes on fish catch and how households respond to these changes. Further, analyses of the effects on consumption of fish will show how temperature potentially alters access to micronutrient-rich food. Our findings suggest the ways that the changing global climate might affect the health and wellbeing of natural resource-dependent communities. FundingFinancial support for this project was provided by the US Agency for International Development (USAID) through the Rice Field Fisheries Enhancement project and Cornell University's David R Atkinson Center for a Sustainable Future Postdoctoral Fellows Program. The contents and opinions expressed herein are those of the authors and do not necessarily reflect the views of USAID or the US Government.

Quality and Safety of Cambodian Rice

Quality and Safety of Cambodian Rice

A Study on Cambodian Rice Farming: Comparative Analysis on Aromatic and Non-Aromatic Rice Farming in Voatkor Commune, Battambang Province

A Study on Cambodian Rice Farming: Comparative Analysis on Aromatic and Non-Aromatic Rice Farming in Voatkor Commune, Battambang Province

Quality evaluation, fatty acid analysis and untargeted profiling of volatiles in Cambodian rice

This study provides the first investigation of the physical traits, pasting properties and volatile compounds of Cambodian rice cultivars, including traditional, improved, and improved traditional varieties, allowing for their differentiation as high and low quality rice. Analysis of the grain quality traits illustrates interesting features of traditional varieties and correlations between traits that assist with understanding texture. Untargeted profiling of volatile compounds shows that high quality fragrant varieties not only contain 2-acetyl-1-pyrroline but also several other compounds, including aldehydes, alcohols and 2-alkylfurans that contribute to overall aroma. Moreover, low odour threshold volatile compounds, which can be derived from the oxidation of unsaturated fatty acids, were more abundant in the fragrant varieties. The percentage area of both oleic and linoleic acid were found to be significantly different among the rice varieties tested. Such findings suggest that unsaturated fatty acids in milled rice contribute to rice fragrance, and thereby to overall quality.

Biological Control of Brown Leaf Spot Disease Caused by Curvularia lunata and Field Application Method on Rice Variety IR66 in Cambodia

Curvularia lunata was found to cause a serious rice brown leaf spot in Cambodia. This is the first report of brown leaf spot on rice in Cambodia. All isolates were tested for pathogenicity. Dual culture antagonistic tests showed that Chaetomium cupreum inhibited sporulation of C. lunata when compared to the control. In a pot experiment , C. cupreum significantly reduced the incidence of brown leaf spot caused by C. lunata . After application of a spore suspension of C. cupreum , Chaetomium -biofungicide and chemical fungicide (tebuconazole) to rice seedlings inoculated with C. lunata , the disease was reduced by 68.79 %, 75.80 % and 72.41 %, respectively. In a field trial, the chemical method gave the best results in all plant parameters, followed by the good agricultural practice (GAP) and organic methods. The chemical method gave the highest panicle/plant, panicle length, panicle weight, grain weight/plant which were different from the GAP and organic methods. The chemical method also gave the best results in filled grain panicle -1 , unfilled grain panicle -1 , grain weight plot -1 , dry hay weight plot -1 , biomass weight plot -1 and harvest index, and was significantly better than the GAP and organic methods.