Abstract:
The production and storage of maize are threatened by a wide range of pre-and post-harvest
pests like maize weevils (sitophilus zeamais). Maize weevil (sitophilus zeamais) causes
significant economic losses and endangers food security. Botanical pesticides are now a better
option for controlling weevils as alternative to synthetic insecticides. The purpose of this study
was to determine effects of methanol and diethyl ether extract of Azandrichta indica and allium
sativum and synergistic extract against maize weevils (sitophilus zeamais) mortality. The plants
materials were collected, air dried in the shade, powdered, and made into tinctures using the
mechanical blender. One handered gram Powders of A.indica seeds were socked with 300ml of
methanol (99.9%) and 300ml of diethyl ether (98%) concentration separately, and 100gm of
bulbs A. sativum plant powder also were socked with 300ml of methanol (99.9%) and 300ml of
diethyl ether (98%) concentration separately and shaken for 72 hours. MIC and MWC of the two
plant extract against F1 progeny also determine .For the weevil mortality test, 100 grams of
grains were mixed thoroughly with 0.5 gm, 1 gm, and 2 gm powder from each plant materials
and the combination of them per100gm of grain in the jars by using completely random design of
the experiment with three replications with probable sampling techniques. Ten adult weevils
were added, and covered with muslin cloth, held with rubber bands, and left at room
temperature. Then, weevils’ mortality, grain weight loss and seed germination was assessed and
data can be collected by observation. The IBM SPSS 25 version and ANOVA procedures were
used to analyze the data. The finding results, all botanical powder significantly resulted in weevil
mortality, low seed damage and weight loss. The botanical powders did not affect the
germination capacity of maize seed. 2 g and 1g Methanol extract of A. indica and Methanol
extract mixture were highly significant than the rest of the treatments which was comparable
with Malathion 5% dust (P <0.05) after 15th days. But both Methanol and Diethyl extract of
A.sativum was the least effective compared to the botanicals and the standard check, but
significantly (p<0.05) better than the untreated check (P <0.05). In general, both Methanol and
Diethyl ether extracts of A. indica and mixture of A. indica and A.sativum found to be the most
effective treatment against maize weevil on stored maize grain. I recommended to the farmers
to use both Methanol and Diethyl ether extracts of A. indica seeds, A. sativum bulbs and the
mixture of them, to control maize weevil.
Keyword: Insecticidal activity, Maize, Plant extracts, Sitophilus zeamais
