The maize weevil,
Sitophilus zeamais Motschulsky, is considered one of the most important pests of stored grains. Plant powders from nine seasoning spices were tested in the laboratory to control
S. zeamais at 0,5, 1, 2 and 4% (w/w). The variables evaluated were mortality and emergence (F1) of adult insects, grain weight loss and grain germination. The repellent and fumigant effects were evaluated at concentrations of 0.5, 1, 2 and 4%; the experimental design was completely randomized, with four replicates, and the group of treatments was repeated three times. The highest mortality percentages were obtained with
Piper nigrum
L. at 1% (83.4%), 2% (97.6%) and 4% (100%). The lowest adult insect emergence was obtained with the same treatments more
Capsicum annuum
var.
longum Sendtn.,
Cinnamomum zeylanicum
Blume and
Pimpinella anisum
L. at 4% (w/w). No significant differences were recorded as regards grain weight loss and germination. All the plant powders tested had a repellent effect on
Sitophilus zeamais
and no fumigant effect was recorded.
