الفهرس 
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Abstract
The present investigation was directed to study ultra-structure of the greater wax moth and the effect of some natural oils on the greater wax moth, Galleria melonella L.
The ultra-structure of Galleria mellonella:
Owing to ultura-structure studies, six types of sensilla on antenna of this insect were found: Those are; trichoid, chaetica, styloconic, coeloconic, basiconic and auricilia sensilla. Trichoid sensillum was only observed on the eye between omatidia and in the end of the leg between the two claws. In genetalia at the end of insect it was found two types of sensilla trichoidea and chaetica.
Oils used:
Five essential oils were tested against larvae (middle and late instars) and pupal stages of the pest. The tested oils were Lemon, Citrus limon; Camphor, Eucalyptus globules; Mint, Mintha spicata; Ginger, Zingiber officinale and Thyme, Thymus vulgaris.
The above natural oils were tested, in the line of trying to find out whether they can be used as insecticides against larvae and pupal stages of the pest.
Toxicity in middle larva stage:
Toxicity results of oils against middle instar larvae of greater wax moth indicated that mint and ginger were the most toxic oils with LC50 values 17.29 and 17.72µl/ml, respectively. The other oils had low Larvicidal toxicity than these oils.
Toxicity in late larvae stage:
Toxicity results of oils against middle instar larvae of greater wax moth indicated that mint and ginger were the most toxic oils with LC50 values 71.81 and 81.19 µl/ml, respectively. The other oils had low Larvicidal toxicity than these oils.
Toxicity in pupa stage:
The above essential oils were investigated against pre-pupal stage (one day old) by using dipping technique. Based on the LC50 values the tested oils could be arranged in descending order of toxicity as follow: 1.52, 14.28, 27.13, 31.70 and 36.02 for mint, ginger, camphor, lemon and thyme oils respectively.
Effect of oils used on sensilla:
After larvae treated in middle instar with oils (lemon 4µl, mint 5µl) the moth emerged were examined under scanning electron microscope to observe the differences in sense organs (sensilla) between them and normal strain. It was observed the obvious deformities in treated strain in sense organs of antennae.
In general, from the above mentioned results it could be concluded that:
1- Mint oil was the most toxic followed by ginger and thyme, while the least oils were camphor and lemon respectively.
2- The toxicity of oils against larvae and pupae of the greater wax moth depend on the plant species, and the stage of the pest.
3- It was found deformities in treated strain in male and female but it was more in male.
4- Many swelling was found in different sensilla; bended in sensilla trichodeum, the abnormal view of antenna and its sensilla in the case of two oils was noticed.