The Intensity Distribution of Cacao Pod Rot Disease (Phytophthora palmivora Butl.) in Smallholder Plantation in North Maluku Indonesia

Abstract

One of important diseases in cacao is pod rot disease. Production loss caused by the disease in Indonesia and other cacao producer countries is more than 30% every year. The research aims to find out the incidence and intensity of cacao pod rot disease in smallholder plantation areas and their distribution pattern in North Maluku.

The research is conducted in West Halmahera and South Halmahera regencies in four locations with different altitude in three repetitions. Plant sampling is conducted systematically. In every experience unit, five observation sub-plots are determined. The number of plant sample for every observation sub-plot is ten plants; therefore, the number of total plant sample in every smallholder plantation is 600 plants. Observation variables include cacao pod rot disease incidence, intensity and distribution pattern in North Maluku.

Research result shows that the average of pod rot disease incidence based on the altitude is 12.27% (at 8-15m a.s.l), 18.76% (at 18-30m a.s.l) and 20.70% (at 186-210m a.s.l) for infected pod incidence and for infected plant incidence is 64% (at 8-15 m a.s.l), 68,67% (18-30 m a.s.l), 84% (at 55-76 mdpl), and 84,67% (at 186-210 m a.s.l). In average, the intensity of cacao pod rot disease in various altitudes is 27,20% (at 8-15 m a.s.l), 27,87% (at 18-30 m a.s.l), 36,00% (at 55-76 m a.s.l), and 39,87% (at 186-210 m a.s.l). The distribution pattern of disease intensity is distributed evenly in all observation locations in North Maluku with the highest infection intensity is 39.87% (moderate). Result from comparison test (t-test) indicates that there are significant differences on disease incidence and intensity among altitudes except between 8 – 15 m a.s.l and 18 – 30 a.s.l.

Keyword : Theobroma cacao, pod rot, altitude, desease incidence and intensity