Research on foul fruit disease of cacao plants (Theobroma cacao L.) was conducted in the Betung village, Kumpe hilir district , Muaro Jambi regency. This study aims to know about foul fruit diseases and its precentage of illness attacking. Simple Random Sampling was use to determine the samples in this research.The samples weredone in public cocoa farm, that had been stratified base on land passing in level. The symptoms foul fruit desease was observed caused by a phytopthorapalmivora fungus, and those data were entirely collected calculate followed by found out the precentage of attacking fruit. Identification of pathogenic disease was done at Batanghari University laboratory. The result showed that there were the attacking of foul fruit disease caused by a phytophthora palmivora fungus on passing in land was 60.4 % which was means it was hard level of disease as more than half cocoa fruit were foul. While it showed a light of disease attacking on unpassing in land.it’s only 7.32 % foul fruitKeywords : Foul Fruit Disease of Cacao Plants, Phytophthora palmivoraPenelitian ini untuk mengkaji penyakit busuk buah serta persentase serangannya pada tanaman Kakao (Theobroma cacao,L.), dilakukan di desa Betung, kecamatan Kumpeh Ilir kabupaten Muaro Jambi. Teknik pengambilan sampel menggunakan metode Simple Random Sampling, sampel tanaman dipilih secara acak di perkebunan kakao rakyat yang sebelumnya sudah dilakukan pengelompokan berdasarkan derajat keterawatan kebun. Pengamatan dilakukan terhadap gejala penyakit busuk buah yang disebabkan oleh jamur Phytopthora palmivora, kemudian dikumpulkan data dengan menghitung seluruh buah baik yang sehat maupun yang sakit sehingga didapat persentase tanaman terserang. Identifikasi terhadap pathogen penyakit dilakukan di Laboratorium Universitas BatanghariHasil penelitian menunjukkan bahwa persentase serangan penyakit busuk buah yang disebabkan oleh jamur Phytophthora palmivora pada kebun yang tidak dirawat adalah 60.4 % yang berarti serangan penyakit ini termasuk berat karena lebih setengah buah kakao terserang penyakit. Sedangkan pada kebun yang dilakukan perawatan intensif serangan penyakit busuk buahnya 7.32 % ini berarti serangan penyakit ringan.Kata Kunci : Penyakit Busuk Buah Kakao, Phytophthora palmivora
PENYAKIT BUSUK BUAH TANAMAN KAKAO (Theobroma cacao L. ) SERTA PERSENTASE SERANGANNYA DI DESA BETUNG KECAMATAN KUMPEH ILIR KABUPATEN MUARO JAMBI