Onion is a Horticultural crop that stands for the prime need in Indonesia. However,
from the production side, it is not satisfiying enoung. This is caused by several
factors such as cultivation techniques, environmental conditions and disease
disorders in onion plants. Nowadays, disease in onion plants is assumed to be
dangerous problem and still continously happens. Therefore to solve this problem,
aplication of onion disease diagnosis is developed. This system works by using
depth first search method based on mobile web to help the problems faced by the
onion farmers, so that later can minimize crop failure. This system will then perform
a diagnosis based on the symptoms that have been selected, if the symptoms are
selected according to the rule it will come out the diagnosis. But if the symptoms
are not in accordance with the rule it will appear illness information is not found.