One of the first departments established at the UP College of Agriculture.
Teaching unit for the first five years with a lone teacher and an offering of two one-year courses, Zoology and Economic Entomology.
Dr. Leopoldo B. Uichanco was the first Filipino chairman of the department
Eight years after the UP College of Agriculture was established, it was born in a tiny, one storey, three room building.
The task of organizing and building up a status as a distinct academic unit for plant pathology was awarded to Dr. Otto A. Reinking, who became its first Chairman.
Dr. Gerardo O. Ocfemia is known as the father of Filipino Plant Pathologists.
Began as a division at the Department of Botany where Dr. Jose R. Velasco was the department chairman.
During the 1960’s, the Weed Science Division was headed by Dr. Marcos R. Vega. Weed Science was a major field of the BS Botany program
In 1970, the Weed Science Division became part of the Department of Agronomy. Consequently Weed Science became a field of specialization
of the BS Agriculture major in Agronomy program.
Reorganization and clustering of the College of Agriculture (CA) occurred.
The Crop Protection Cluster emanated from the Departments of Entomology and Plant Pathology, division of Weed Science
and the National Crop Protection Cluster
The CA de-clustered and became the College of Agriculture and Food Science (CAFS).
Weed Science became a major option in the BS Agriculture program side by side Entomology and Plant Pathology
The Institute of Weed Science, Entomology and Plant Pathology was established