The invention provides a multi-
modal agricultural
knowledge graph construction method based on a large
language model. The method comprises the following steps: firstly, carrying out standardized preprocessing on multi-
modal data such as texts, images and sensors in the agricultural field; constructing an initial agricultural knowledge ontology by adopting a top-down and bottom-up combined
mixed mode, and identifying a new concept based on a large
language model to realize dynamic updating of the ontology; fusing the text entity, the image
feature vector and the sensor
time sequence feature into a multi-
modal triple and storing the multi-modal triple into an
image database; and finally, analyzing a user query intention by using a large
language model, and performing multi-hop path reasoning in combination with a graph neural network to generate a structured result. The problems that in the prior art, multi-modal fusion is difficult,
knowledge updating lags behind, and semantic reasoning capacity is weak are solved, the integrity, timeliness and
intelligent decision support capacity of the
knowledge graph are improved, lightweight deployment and a
federated learning mechanism can be combined, an
edge computing scene can be adapted, and the
data privacy protection requirement is met.