Which pathogen is responsible for rice blast disease?

Rice blast disease is caused by the pathogen Pyricularia grisea, which is a well-known fungus primarily affecting rice crops. This pathogen is characterized by its ability to produce conidia, which are asexual spores that can spread rapidly, leading to significant yield losses in infected plants. The symptoms include irregularly shaped lesions on leaves, panicles, and nodes, contributing to reduced photosynthetic area and ultimately impacting plant growth and development.

While the other pathogens listed are associated with different plant diseases, they do not cause rice blast disease specifically. For instance, Pythium ultimum is primarily involved in damping-off diseases, Rhizoctonia oryzae-sativae is known for causing sheath blight in rice, and Fusarium oxysporum is associated with various wilt diseases. Thus, identifying Pyricularia grisea as the causative agent of rice blast disease is crucial for effective disease management and understanding the specific threats to rice production.