Maria Praksedis Tamonob Pengarang ADRIANA FANGGIDAE Dosen Pembimbing 2 DERWIN RONY SINA Dosen Pembimbing 1 Yulianto Triwahyuadi Polly Penguji 2 Sebastianus Adi Santoso Mola Ketua Penguji Clarissa Elfira Amos Pah, S.Kom,.M.T.I Penguji 1

EXPERT SYSTEM FOR DIAGNOSIS OF PESTS AND DISEASES IN MANGO CROPS USING FORWARD CHAINING AND CERTAINTY FACTOR METHODS Maria Praksedis Tamonob, Derwin R. Sina*, Adriana Fanggidae** The mango plant (Magnifera Indica-L) is an annual fruit plant originating from India. Mangoes then spread to Indonesia brought by Indian traders around the 4th-5th century BC. Mango production in Indonesia in 2021 will be 2.84 million tons, which has decreased by 2.07% from the previous year which was 2.9 million tons. This decline was caused by various factors, one of which was pests and disease. The solution to overcome the problem description above is to create an expert system that can diagnose diseases in mango plants using forward chaining and certainty factor methods. Users can consult this system to diagnose diseases in mango plants and find solutions to the problems they experience. Based on the results of system testing using 50 test data and a threshold limit of 80%, it is known that the forward chaining and certainty factor methods have proven capable of being applied in diagnosing diseases and pests on mangoes with an accuracy level of 96%. Keywords: Expert System, Mango Plant, Forward Chaining, Certainty Factor. * 1 stAdvisor I ** 2 nd Advisor II