Studies on spatial and temporal distribution of white coffee stem borer (WCSB), antestia
bug and coffee berry borer (CBB) were carried out between September 2007 and
August 2008 in medium altitude (Lyamungo) and high altitude (Kilema) areas in
Kilimanjaro region. Specifically, the study aimed at establishing the species
composition and spatial distribution, the temporal variation in abundance, and the
relative importance of three pests in coffee ecosystems. A multistage random
sampling method was used to select farms in two locations where in each location,
one ward was selected and within each ward three villages were chosen, and in each
village fifteen farms were randomly selected for the study. In each farm, nine trees
were selected to make a total sample size of 810 trees. Insects’ were counted every
month to establish their population dynamics. WCSB was dominant in both high and
medium altitudes while antestia bugs were dominant at medium altitude and less
dominant in high altitude. CBB was dominant at medium altitude and no records were
noted in the high altitude. High population of antestia bug and CBB were recorded
during the short and long rains when flowers and fruit developments were set. WCSB
were also observed to increase gradually during short and long rains, which was
established as their reproduction period. WCSB was found to be more damaging (44.8
to 67.7 %) than CBB (0 to 12.5%). The study shows that WCSB was more prevalent
in the sparse shade while antestia bug and CBB were more prevalent in dense shade.
Since WCSB is abundant in all locations and was the most damaging insect pest in the
study area, it is recommended that more attention should be focused on management
of this pest.
Tanzania Coffee Research Institute
(TaCRI)