We have established a clonal porcine subcutaneous preadipocyte cell line for the first time. This cell line, named PSPA, shows a fibroblast-like phenotype and keeps on growing under growth medium even after reaching confluence. Adipose conversion occurs only when confluent cultures are stimulated with insulin, dexamethasone, biotin, pantothenate, and octanoate. Following exposure to this differentiation medium, growth was arrested immediately without mitotic expansion and PSPA cells exhibited a marked increase in intracellular lipid accumulation accompanied by changes in gene expressions directly related to fat metabolism and also in extracellular environments. Since PSPA cells were established, it has become possible to end the discussion over whether there is species specificity in the adipose conversion between pig and mouse by comparing PSPA cells and 3T3-L1 cells, the most widely studied preadipocyte cell line. Consequently, we demonstrated that responsiveness to inducers and fatty acid composition was unequal, despite being treated with the same media. Thus, species-specific differences indeed exist in adipogenesis between these two, meaning that PSPA cells would be an in vitro model specialized to improve understanding of pig adipocyte growth and differentiation in controlling the carcass fat content of pigs.

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Water-soaked brown flesh disorder of peach (Prunus persica (L.) Batsch) fruit, which occurs in unpicked fruit near harvest time, has been a problem in Japan since the 1990s. The affected fruit share the characteristics of more mature fruit in that the fruit are large, sweet, and soft. It has also transpired that high-quality; high-value fruit are more sensitive to the disorder, which exacerbates economic losses. The most susceptible regions of the fruit are those with high sugar content, although the symptoms are not clearly linked to specific cultivars. Investigations into the cause(s) of water-soaked brown flesh disorder of peach fruit have just started, and reports are limited to Japan. In this review, published information about the disorder is reviewed, and a hypothesis for the occurrence of water-soaked brown flesh disorder in peaches is presented.

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This study aimed to verify the accuracy of inundation analysis by comparison with field-survey results for a small agricultural earthfill dam that failed due to heavy rain. In Japan, dam failures are caused by concentrated heavy rain or large earthquakes. Potential inundation areas are displayed on municipal “Hazard Maps” to reduce the risk of damage to downstream sites. However, the accuracy of inundation analysis for small earthfill dams has never been verified through comparison with field surveys.The following work was completed; i) the effect on the downstream gradient was verified by a simplified (one-dimensional unsteady flow) analysis for a case of dam failure; ii) the water depth and width of flow path in inundation areas were compared based on differences in peak outflow; and iii) the effect of the culvert structure blocked by flood debris downstream was also verified by comparing the result of analysis and the field survey. The following results were obtained: i) From the simplified analysis, the downstream water depth was sensitive to changes in outflow distribution from the dam breach section: ii) In the inundation analysis, using the peak outflow prediction equation proposed by Costa (1988), the water depth was deeper at the center of the flow path and the flow path was wider: iii) The water depth around the blocked culvert structure matched the field-survey results (the elevation data of the meshes around the culvert structure were raised to simulate the blocked structure).

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Solving big problems requires accurate information. Rice in the area of Cambodia near Vietnam was extensively damaged by the brown planthopper (BPH) from 2007 to 2009, with all districts in Takeo province in the area of Cambodia near Vietnam severely affected. How did farmers learn of methods to protect rice plants? This study seeks to reveal how methods to control the BPH were diffused in Cambodia through interviews with farmers, local governmental officials, and village chiefs in the target province. The farmers stated that they controlled the BPH with nets and beating as physical controls and spraying mixed oil & ash and chemical pesticides as chemical controls. They tended to source their own information and experiences of neighbors, government officials, and pesticide sellers, while farmers in three communes very severely affected by the BPH infestation followed the advice of sellers in employing pesticides. Further, most local government officials and village chiefs recommended using nets and spraying oil mixtures and chemical pesticides. The flow of information from the resource to individual farmers seemed to be linked to the level of BPH infestation.

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The fewer the water resources, the greater the demand and the more important water becomes. This applies in Egypt, where rainfall is rare and most of the country is desert, except for a narrow strip of cultivated land and urban areas along the Nile river course. Like other large rivers, the Nile Delta region is characterized by large tracts of rich fertile agricultural land, overpopulation and unique and delicate environmental conditions caused by mixing drainage and freshwater. Managing these unique natural resource areas has become increasing critical, given the threat to the ecological balance in these areas due to an increase in water exploitation to boost population and the development of resources. Accordingly, the performance of water-delivery systems, particularly irrigation systems, must be clearly defined and assessed under these current or expected stressed conditions. This paper highlights irrigation, drainage and water-management projects in Egypt and presents the positive and negative effects as well as the role of government and users in operating and maintaining the system. The objective is to identify significant research programs and projects carried out over the last three decades that have impacted on irrigated agricultural practices in Egypt. The study documents both successful and failed cases of direct and indirect research uptake. Specific recommendations for increasing the research uptake, improving the penetration of research results and taking corrective measures to strengthen and encourage research uptake to irrigation and drainage practices are highlighted.

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Agricultural mitigation and adaptation technologies developed and assessed in a project organized by the Agriculture, Forestry, and Fisheries Research Council were evaluated on an economic basis using a regional–production model, an applied general–equilibrium model, a discrete choice experiment, and a world–food model. Climate–change effects on food production were also evaluated using these models. This paper presents: (1) an overview of the sub–project structure and goals, (2) the six results of the sub–project, and (3) the future direction of the sub–project. Results of these models were subsequently integrated into a single regional model, whereupon selected technologies were economically evaluated using the models developed in the sub–project. The main results are as follows: (1) delaying the introduction of high–temperature–tolerant rice by one year will result in an average economic welfare losses of 429 million yen per year in Japan; (2) higher temperatures under RCP4.5 scenario will cause an increase in 0.2 t ha^-1 rice yield in Japan in 2040s compared to a constant climate variables case; (3) the target reduction rate of GHG, which is 25% of the 1990 figure, will imply benefit–cost ratios greater than one for most CH₄–suppression technologies developed in the project.

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This paper uses the dynamic computable general equilibrium (DCGE) model to evaluate the economic impact of technologies developed to foster adaptation to climate change in domestic rice production, related food industries, and economic welfare in Japan, where high temperatures in 2010 led to rice quality deteriorating and other serious problems over and above a mere decline in output. Three scenarios were simulated: one without temperature change, one with temperature change but rice cultivars unchanged, and one with both an increase in temperature and the adoption of high temperature-tolerant rice varieties. Our simulations indicate that new rice cultivars with high temperature tolerance would reduce economic welfare losses from 264 to 118 billion yen during the simulation period. Paddy-rice farming production increased because product prices increased. Farming inputs also rose correspondingly, triggering an increase in agricultural land rents. Non-agricultural household and small-scale paddy rice-growing household suffered welfare loss. Conversely, medium- and large-scale paddy rice-growing and other farming households saw their welfare boosted. These differences were attributable to the impact of changes in agricultural land rents to their total income. All impacts, not only on economic welfare but also production in the case with new cultivars of high temperature-tolerant rice were smaller than in the those without such cultivars, which indicates that adopting new adaptive technologies eases the economic impact of a warmer climate.

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In the present world affected by climate change, developing agricultural technologies to adapt to climate change is one of the most important challenges to mitigate the impacts of climate change on food security. In fact, many researchers and engineers are also working to develop adaptation technologies.If there is a low-cost, easy-to-use tool to evaluate such technologies, it will facilitate initial evaluation to consider the appropriate technical development perspective. Accordingly, this paper tries to develop a simple model structure for the tool and consider how best to use the evaluation tool, based on the achievements of a previous study. To enable simple calculations in a spreadsheet, an input-output model is applied to the model structure, assuming minimal impact of shocks on national nominal income. Comparisons of projection results by two alternative candidate models with those by a comprehensive but complex simulation model including flexible and realistic assumptions show that the developed simple models result in realistic and robust projections of real consumption and social welfare index. Accordingly, an evaluation tool based on simple model structures will enable a low-cost initial evaluation with social welfare as a criterion.

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Economic simulation systems such as computable general equilibrium modeling have been used to predict the impacts of climate change on the economy and evaluate countermeasures to mitigate its effects. In this regard, forming an assumption about international trade in agricultural products becomes problematic if limited information is available on substitution between domestic and imported agricultural products. This study examined the substitution patterns of Japanese consumers between domestically produced and imported agricultural products such as broccoli, kiwifruit, rice and apples using discrete choice experiments. Three web surveys were conducted in January 2011, February 2012 and January 2013 to gather responses to the discrete choice experiment questions for each of the four products. The responses were analyzed using the error components multinomial logit model. The results showed that the substitution of imported products for domestic sources was relatively large in the case of broccoli and kiwifruit and relatively low in the case of rice and apples. Although economic simulation systems sometimes assume that substitution patterns between domestic and imported products are fixed for different kinds of agricultural products, our results indicate that this assumption does not necessarily apply in all cases.

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This study empirically identifies the impact of global-warming-induced climate change on Japan’s agricultural production using panel data. First, we constructed panel data; combining time-series data from 1995 to 2006 for a cross-section of eight regions in Japan. Next, we conducted a static panel data analysis, using a function for agricultural products incorporating labor and three weather variables (temperature, solar radiation, and precipitation.) From the estimation results of the production function, we selected the production function with the aforementioned labor and weather variables and found that the rising temperatures and precipitation and falling solar radiation caused by climate change have reduced the rice production, while rising temperatures and precipitation have reduced the vegetable and potato production in Japan. Second, we conducted dynamic panel data analysis, using a production function for agricultural products incorporating labor, a one-period lagged output, and the same three weather variables. Based on the estimation results of the dynamic panel data model, we selected the production function for agricultural products using only the labor and three weather variables and found the same results for both the rice production and vegetable and potato production in Japan. Based on the estimated results of the static and dynamic-panel data models for variable mean annual temperature, which serves as a proxy for climate change, we concluded that an increase of 1°C in mean annual temperature would reduce rice production by 5.8% in the short term and 3.9% in the long term, and vegetables and potatoes productions by 5.0% and 8.6% in the short term and long term, respectively.

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The incidence of extreme rain is expected to increase with climate change and affect rice productivity in Japan. This study aims to evaluate the impacts of long and heavy rain on Japanese rice total-factor productivity (TFP) by estimating causality functions. We measured rice TFP by using the TörnqvistTheil and Malmquist indexes for dependent variables and predicted, the influences of future temperature and rain on rice TFP by the causality function associated with crop models and a hydrological model based on climate projections from the global-climate model (GCM). The results initially showed no significant differences between Törnqvist-Theil and Malmquist indices in the effects of climate factors, although some differences emerged in the causality of socioeconomic factors. Second, the effects of rain were always negative, and absolute TFP elasticity against rain was lower than temperature via yield and quality, but poorly drained surface water as well as flooding reduced rice TFP by 2.5 to 4.5%. Third, changes in predicted rainfall under future climate change caused annual rice TFP to fluctuate, and an impact of rain on TFP fluctuations exceeded that of temperature via yield and quality. This is due to significant variations in annual rainfall, even though the measured elasticity against rain was low. Based on these findings, the implications for research and policy-making are discussed.

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Future climate change will affect rice production, but whether these changes will be beneficial or detrimental is unclear. The present study evaluates the effect of climate change on Japanese rice production, rice price, agricultural income, and regional economies by using a recursive-dynamic regional computable general equilibrium (CGE) model, which is associated with crop-growth and crop-quality models. Simulation results demonstrate that future climate change will increase overall Japanese rice production nationwide, but that the price of rice will decrease. As a result, agricultural income will decrease, despite increased production in northern and eastern Japan, such as Hokkaido, Tohoku, and Kanto (including Niigata prefecture). Climate change will not benefit rice farmers in these regions. However, the western region will benefit, despite the decrease in production, and the consumer surplus in most regions will increase. This happens because rice demand is inelastic and an increase in production results in a serious decline in price, which more than offsets the effects of climate change on production. As such, the impacts of climate change are complicated and differ by region, so a CGE model can provide useful information to consider policy countermeasures.

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Annual crop yield forecasts are necessary for analysis because evaluating climate–change impacts on world food markets requires supply–response functions, including output prices of the prior year. This research was undertaken to develop yield–response functions of the world food model to evaluate climate–change effects by incorporating a crop model into the yield–trend function. Yield–trend functions of rice, wheat, maize, and soybeans were obtained by estimating logistic functions or linear functions with a logarithmic time–trend term and climate variables. Furthermore, temperature and solar–radiation elasticities of yields were calculated using a crop model of the FAO and IIASA. The functions of the maximum rate of gross biomass production and the maximum net rate of CO₂ exchange of leaves in the crop model were modified by introducing cubic spline interpolation and logistic functions. Smoothing these two functions alleviates drastic changes, but reveals small changes in the elasticities of crop yields compared to the kinked functions and these more realistic elasticities can improve the evaluation accuracy of climate–change impacts on crop supply and demand. These variable elasticities of temperature and solar–radiation were inserted into the yield–trend functions, whereupon the global effects of changes in climate variables, including rainfall, were analyzed. The changes in yields obtained using climate variables of two of the four RCP scenarios were compared with the baseline, for which climate variables were fixed. Results of trend analyses show that yields of rice, wheat, maize, and soybeans under RCP8.5 are lower than those under RCP2.6, except for wheat in China. Results of geographical analysis show that climate change can be expected to affect wheat and maize productions in low–latitude countries. Furthermore, results suggest that climate change will depress rice production in sub–Saharan African countries in the 2040s.

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