الفهرس 
Insects tested and Rearing ConditionsOnly 14 pages are availabe for public view
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Abstract
Sitophilus and Callosobruchus species are major pests of stored
grains and grain products in the tropics and sub-tropical regions. The
cowpea beetle, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae),
is a cosmopolitan field-to-store pest ranked as the principal post-harvest
pest of cowpea in the tropics. It causes substantial quantitative and
qualitative losses manifested by seed perforation and reductions in
weight, market value and germination ability of seeds. The rice weevil,
Sitophilus oryzae (L.) (Coleoptera: Curculionidae), is another important
stored-grain pest. This species feeds on a variety of cereals or grains,
particularly wheat and rice, which are among the most frequent sources
of nutrition. Control of these insects relies heavily on the use of synthetic
insecticides and fumigants, which has led to problems such as
disturbances of the environment, increasing costs of application, pest
resurgence, pest resistance to pesticides and lethal effects on non-target
organisms in addition to direct toxicity to users (Jembere et al., 1995;
Okonkwo and Okoye, 1996). Thus, repellents, fumigants, feeding
deterrents and insecticides of natural origin are rational alternatives to
synthetic insecticides. Herbal products are one potentially important
source. Essential oils are secondary metabolism products in plants. These
oils have strong aromatic components that give a plant its distinctive odor, favor, or scent (Koul et al., 2008). A strong connection between
medicinal and pesticidal plants was reported by several researchers (Yang
and Tang, 1988).