Abstract:
Crop sanitation, i.e. destruction of crop residues, has been hypothesized to lower banana
weevil damage by removing adult refuges and breeding sites. Although it has been widely
recommended to farmers, limited data are available to demonstrate the efficacy of this
method. The effects of crop sanitation on banana weevil populations and damage were
studied in an on-station trial in Uganda. Treatments included low, moderate and high levels
of sanitation. Banana weevil populations, estimated by trapping and mark and recapture
methods, were lowest in the high sanitation treatment. However, banana weevil damage
was either not significantly different among treatments or lower in low sanitation
treatments. Similarly, increases in crop sanitation level were not reflected in higher yields.
The data from this trial suggest that crop sanitation is not an effective means of managing
banana weevil and contrasts with results from an on-farm study in which sanitation reduced
both weevil numbers and damage. Possible factors explaining the different outcomes of the two studies are discussed.