In the movie Interstellar, the Blight is a plague that has ravaged almost all the remaining food sources on Earth. It is a microorganism that affects crops one by one, to the extent that corn is the only viable crop left. The movie does not mention any other plants suffering from the Blight. The Blight is the primary antagonist in the movie, and it is killing off the worlds food crops. The movie does not provide a clear explanation of how the Blight came to be or how it spreads. However, some scientists suggest that the environment presented in the movie is one low in species diversity, which lacks the resilience to withstand something as simple as a plant disease. The Blight is a fictional concept created for the movie, and it is not based on any real-world scientific phenomenon.