Model of rice blast disease under tropical climate conditions

The Pyricularia oryzae is a fungus that leads to rice blast disease (RBD) in rice cultivar (Khao Dawk Mali 105), which grew in Thailand. The weather condition is one of the factors that affect plant and disease development. A Mathematical model is a useful tool for studying the dynamics and severity of plant disease. In this research, the severity of RBDs is simulated under environmental conditions, temperature, humidity, and dryness, in different parts of Thailand. The adopted model is developed to investigate the pathogen's life cycle together with the disease development in the paddy field. The result illustrates that temperature, the climatic factor, is the highest affected by the disease severity. In addition, the disease severity is high when it is low temperature and high humidity. On the other hand, the low severity also tends to be inverse in high severity. Moreover, the model can capture the outbreak period and predict the spatial distribution of the disease severity under climate conditions. (C) 2020 Elsevier Ltd. All rights reserved.