Because the volume of data that must be managed in large-scale farming has become enormous, we developed a mobile field computer to record tractor operations for analysis by a cloud-computing-based farm management system. The newly developed field computer running Microsoft Windows is mounted in the cabin of a tractor and acquires data from sensors attached to implements and the tractor’s GPS receiver via a controller area network, and sends the data to a cloud server through the Internet. The user of the system can view and use the data to aid farm management decision in a web browser. This paper describes the acquisition of spraying data and its analysis to verify the operation of the system. The server software simulated the change in the dispersion density of the spray from the path and working speed of the tractor, which was displayed in the web browser.

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The oriental fruit fly and its relatives, Bactrocera dorsalis complex Hendel (Diptera: Tephritidae), were eradicated in Okinawa Prefecture in February 1986. No fruit flies were caught in monitoring traps in the next 7 months, but some have been caught every year since then. There are two possible routes of reinvasion: windborne immigration and accidental importation in infested fruits. To assess the risk of reinvasion by windborne immigration, we developed software that calculates forward trajectories from possible sources in Taiwan and the Philippines daily and their intersection with the islands of Okinawa. The reinvasion risk index on a particular day for an island is defined as the number of days when any trajectory from the possible sources passes over the island during that day or the previous 13 days. The trend of the risk index and the number of fruit flies caught in all the monitoring traps are graphed. Windborne immigration is considered possible when any oriental fruit fly is caught and the risk index is >0. The risk index is also mapped to show which islands face the risk. The index is automatically updated daily, making the software easy to use by plant protection officers in the field. At present, the system is used in Okinawa Prefecture and the Naha Plant Protection Office.

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Small farm size and high production costs pose major problems for Japanese rice cropping. We used the Farming-systems Analysis and Planning System database (FAPS-DB) to estimate the effect of improving farmers’ skills and the effect of scale on the production costs of large-scale rice farming. At a scale of 150 ha, the cost per unit of production decreased to around 88% of those at a scale of 50 ha. In simulation analyses in which all operators are either beginners or experts, the cost per unit of production at a scale of 150 ha were 94% of those at a scale of 50 ha in the beginner scenario and 87% in the expert scenario. Thus, increasing experience is effective at decreasing production costs, especially fixed costs and labor costs. At a scale of 150 ha, a higher level of farming skill achieved a greater reduction of production costs. These results suggest that it is important to provide effective agricultural training in order to reduce production costs at the farm and national levels.

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Naturalized raccoons (Procyon lotor) have become a big problem in Japan because they damage crops. In tackling the problem, it will be important to understand the expansion of their distribution. We used a generalized linear model to estimate the cost values of different land use types for the expansion of the raccoons’ distribution in Osaka Prefecture. We then used the cost distance method to predict habitat expansion from the estimated cost values. Expansion into urban areas was limited. Akaike Information Criterion values showed that the cost distance method explained expansion better than the simple distance method (simple distance method: 255.72, cost distance method: 226.05). By analyzing possible routes of habitat expansion from the distribution in 2007 using the cost distance method, we identified three possible routes of entry into Osaka City and one into Sakai City.

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Agricultural information processing systems that utilize GIS-compatible paddy field maps have been proposed. Paddy field maps are usually created manually, but this method is time consuming. We propose a method for the automatic creation of maps. To create paddy field maps, it is necessary to extract and vectorize the field borders. The conventional method for the extraction of borders uses an edge-detection approach combined with edge tracking, but gaps where edges cannot be detected lower the rate of identification. As an alternative, we used evolutionary image processing to create a wood-structure filter from a false-color aerial photograph with a resolution of 2,048 × 2,048 pixels. Our method, designed to automatically create paddy field polygons by evolutionary image processing, scans a paddy field repeatedly to create tone-corrected images with different maximum and minimum pixel values. When the filter was applied to 18 test images that did not overlap, the rate of the identification of fields in which plants were growing was 55.1% ± 24.9%, and the time required to create a field map was 36.5% of the time required to manually create the same map. When the filter was applied to 55 test images that overlapped each other by 50%, the rate of identification was 64.4% ± 20.2%, and the time required was 34.4% of that required to manually create the same map. Thus, the method reduced the time required to create paddy field maps to about a third.

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We examine the consumers’ evaluation of food safety attribute for domestic and imported fresh oranges by a choice-based conjoint analysis in metropolitan Bangkok in Thailand. Our experiment introduces a ‘food safety label’ for oranges of both production origins as a hypothetical certificate in order to evaluate the consumers preference on an explicit information provision of food safety regulation. The estimation result of our survey conducted in 2010 shows that respondents assign a significantly higher willingness to pay value on domestic than on imported ones. And consumers evaluate food safety label positively for oranges from each production origin, however, consumers’ evaluations are indifferent in terms of their willingness to pay for the food safety label between production origins. These findings demonstrate that food safety information provision on products is preferred. And the indifference in terms of willingness to pay for the labels from various origins implies competitiveness with good food safety management and weakness due to mismanagement of the safety regulation on domestic fresh products.

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