Abstract:
This study was conducted in the laboratory of Environment and
Natural Resources Research Institute (ENRRI), National Research
Center.
The study concerned the possibility of usage of aqueous leaves powder
extract of periwinkle plant (Vinca rosea), the aqueous powder extract of
mixure of (leaves, fruits and stems) of Hargal plant (Solenostemma
argel), beside the organic methanol extract of leaves powder of cafure
plant (Eucalyptus camaldulensis), in addition to the use of Nimbecidine
0.03% as a commercial product from Neem, which were used as pest
control agents under laboratory conditions against the third larval instar
of khapra beetle (Trogoderma granarium Everts) feeding on sorghum
seeds. The evaluation was based on the mortality, the molting inhibition
and anti feeding effect on the development of larvae at 2.5%, 5% and
10% concentrations for each of the different treatments, except for the
Nimbecidine 0.03% commercial product which was used as 1.5ml/L
2ml/L and 2.5ml/L concentrations.
The highest concentrations (10%) for all botanical extracts gave the
highest average of mortality beside Nimbecidine 2.5ml/L concentration.
The Eucalyptus 1.28, gave the best mortality followed by the Vinca 0.85,
then the Nimbecidine 0.80 and the Hargal 0.67 respectively. Generally,
the mortality increased with the increase of concentration. The
Nimbecidine gave low average of moulting 1.5 fallowed by Eucalyptus
2.28, then Vinca 2.42 and Hargal 2.71 respectively. Where as the loss of
weight of the used seeds in the experiment, were, Hargal 0.837, Vinca
0.879, Nimbecidine 1.098 and Eucalyptus 1.358respectivelly.