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Web based IPM system for Japanese pear diseases in Japan
I. Farming Diary System for farmers' decision making
K. Sugahara(1), K. Tanaka(1), M. Laurenson(1), T. Ohtani(2), T. Watanabe(1), and S. Umemoto(3).
(1)National Agricultural Research Center, Tsukuba, Ibaraki 305-8666, Japan; (2)Chiba Prefectural Agriculture Research Center, Chiba 266-0006, Japan; (3)Chiba Prefectural Agricultural Junior College, Togane, Chiba 283-0001, Japan

    Japanese pear (nashi) scab is one of the most serious diseases of nashi in Japan. To suppress the scab infections, fungicides are usually applied on a calendar based spray schedule, more than 10 times during a growing season. Increasing environmental concerns make such frequent spraying unacceptable, so accurate timing of fungicide applications has become more important. Combining alternative strategies such as cultural practices and optimally timed chemical sprays is a practical way to control nashi scab. We propose a decision support system assisted by the Internet. It is designed to help farmers and extension officers make decisions about the effective timing of chemical sprays in their orchards.
    The system consists of several subsystems, 1)a knowledge base regarding nashi scab control, 2)simulation models which can forecast the flowering period and the probability of scab infection associated with local weather data, 3)a model of effective fungicide residue, 4)weather data acquisition and retrieval system, and 5)a Web application, Farming Diary System. Farming Diary System enables users to input and retrieve the records of farm management and plant condition using Internet-enabled mobile phones, which are widely distributed and most convenient data-handling devices in Japan. Farmers can access the system in their orchards and immediately acquire information to help their decision making.

PRESENTATION POSTER (PDF 330KB)

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Web based IPM system for Japanese pear diseases in Japan
II. Forecasting models for scab infection associated with weather retrieval system
K. Tanaka(1), M. Laurenson(1), K. Sugahara(1), T. Ohtani(2), T. Watanabe(1), and S. Umemoto(3).
(1)National Agricultural Research Center, Tsukuba, Ibaraki 305-8666, Japan; (2)Chiba Prefectural Agriculture Research Center, Chiba 266-0006, Japan; (3)Chiba Prefectural Agricultural Junior College, Togane, Chiba 283-0001, Japan

To support farmers' and extension staffs' decision making related to fungicide spray against Japanese pear scab, two forecasting models have been developed and implemented for use on the Internet. The first model can estimate flowering date, which is used to time the first and most important fungicide application in the growing season. The flowering date is highly correlated with the maximum density of airborne ascospores. The second model can forecast scab infection probability on pear leaves, as a function of temperature and leaf wetness duration. Two methods are available for estimating the leaf wetness duration, measurement by wetness sensor and calculation from other weather variables, such as rainfall and humidity.
    The models are written in Java, and can run on most computers' Web browser (http://cse.naro.affrc.go.jp/ketanaka/model/). Both weather sources, local weather data collected by users and database system maintained by some organizations, are available to the models through the MetBroker. MetBroker (http://www.agmodel.net/MetBroker/) enables us to access the different kinds of weather database linked with this system. We can incorporate either kind of weather data to forecast site-specific scab infection risk and to optimize spray timing.

PRESENTATION POSTER (PDF 220KB)

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Web based IPM system for Japanese pear diseases in Japan
III. Weather data acquisition system to estimate leaf wetness duration and scab infection severity
T. Ohtani(1), K. Sugahara(2), K. Tanaka(2), M. Laurenson(2), T. Watanabe(2), and S. Umemoto(3).
(1) Chiba Prefectural Agriculture Research Center, Chiba 266-0006, Japan; (2) National Agricultural Research Center, Tsukuba, Ibaraki 305-8666, Japan; (3)Chiba Prefectural Agricultural Junior College, Togane, Chiba 283-0001, Japan

   The duration of wetness on leaves is one of the most important factors associated with the nashi scab infection. We set weather sensors within and outside the canopy of an orchard to estimate leaf wetness duration and utilize those data for the scab infection model. Two set of electronically wetness sensors, flat plate and cylindrical type, were mounted both inside and outside orchard.Temperature (dry and wet bulb), radiation, and wind speed, are also monitored within orchard. Those sensors are connected with a data logger, CR10X, and the weather data were logged at 15 minutes intervals. A laptop PC connected to the logger downloads data every morning automatically and sends it to an office PC, using e-mail over a 64 Kbps Personal Handyphone system (PHS)-based dial-up Internet link. Weather data is in turn automatically transferred from the office PC to the weather server, and stored in a web-accessible database.
   A new leaf wetness estimation procedure was developed, that estimates "wetness" using rainfall and humidity data, from April to the half of May, which is the most important period to protect against the nashi scab. This procedure can be used to estimate leaf wetness where wetness sensor is not available. Mills' model and Duthie's model were proposed to express nashi scab infection severity by wetness duration and temperature.

PRESENTATION POSTER (PDF 676KB)

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