Original Articles: 2016 Vol: 8 Issue: 6
Phythophthora black pod disease of cocoa caused by Phytophthora palmivora: Development of bio-fungicidal package in controlling the disease and the vector by food bait
Abstract
The aim of study was to achieve a ready natural fungicide formulated in use as an effective environmental technological package. The formulation consisted of suspension and pellet due mainly to familiar usage by farmers in controlling particularly Phytophthora black pod disease (PBPD). Natural concept to control spread disease by ant vector was purposed. In fact, it was reported that up to 90% loss of yield in wet season in Sulawesi that is main cocoa production and population. Likely wet season, in dry season, annual significant loss was led by ant as vector. There were three of trials including; firstly, testing citronella (seraiwangi extracted) and cashew nut shell liquid (CNSL) made from cashew husk extracted was purposed to limit lesion disease development in pod surface; secondly, in the field, testing effectiveness in both plant extracted against the pathogen and; thirdly, testing plant extract mixed with food bait for ant as disease vector. The disease incidence was measured by scale level. Disease categorized from 0 (healthy pod), 1 (up to 25% pod lesion), 2 (25-50% lesion), 3(50-75% lesion) to 4 (more than 75% lesion). Disease incidence was measured as following; = Σ( ) 100%; I (disease incidence), U (total of tree infected in each disease category), V (score in each pod lesion), Z (high score). The result, in the lab activity, showed that both 5% and 10% CNSL concentration was greater limit of PBPD development than 5% citronella concentration, both NSCL and citronella treatments showed the lowest disease incidence (only scale 0.25 ~ 6.25% pod damage), and followed by 10% concentration was in score 2.75 ~68.75% of pod damage respectively. By ant control, lower ant population investigated (scale 1.5 or 50 to 200 ant colony) was in 20% CNSL concentration than other trials.