First and fourth larval instars of a sensitive laboratory strain of the cotton leaf worm; Spodoptera littoralis Boisd. were reared on castor Ricinus communis L. leaves; treated with three concentrations (5.0, 10.0 and 15.0%) of water extracts prepared from three different varieties of mulberry leaves; Morus alba var rosa, M. alba var morittiana and M. alba var kokuso -27. Different biological aspects were determined to evaluate the insecticidal effect of the three mulberry varietyleaves. The M. alba var rosa was significantly more lethal to both larval instars of S.littoralis than the M. alba var morittiana and M. alba var kokuso-27 The fourth larval instar was more tolerant to the lethal effect of all mulberry leaf extracts than the first one. The higher the concentration of mulberry leaf extracts the greatest the lethal effect obtained with all treatments. Protein profile of haemolymph samples was monitored for the sixth larval instar of S.littoralis leaves by the 15.0% concentration of all mulberry varieties from the fourth larval instar. Electrophoretic protein analysis showed disappearance of some protein bands in haemolymph samples from treated larvae by M. alba var rosa.

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Cocoons of silkworm Bombyx mori L. were irradiated with four different doses of gamma radiation; 10, 20, 40 and 60 krad to minimize the damaged occurred during storage. Irradiated cocoons were packaged in different kinds of sac materials as traditional gunny, polypropylene, printed paper, thick paper, thin and thick cotton textiles treated with chamomile and propolis powder to overcome. Pest infestation preservation period was six months with one month as investigation interval. Packages of thick paper and thin textile treated materials gave the best results for preservation of cocoons irradiated with higher doses of gamma radiation gave the best results. as there were no resulted damaged cocoons through six months preservation period.Infestation test was carried out by irradiating adults of Dermestes maculates with 10 krad dose of gamma ray and transferred into the treated packages made of different kinds of sac material to investigate their ability for infesting silkworm cocoons. The lowest percentages of damaged cocoons were recorded when irradiated adults infested cocoons stored in thick paper, thin and thick cotton textiles treated packages. Generally the highest damaged cocoons percentages were scored when cocoons preserved in packages made of traditional gunny, polypropylene and printed paper. 20 40 60Infestation and infection kinds * 0.00 0.00 0.00 0.00 0.00 0.00 Investigations intervals (days) **

his work aimed to study the pathogenic effect of the Paenibacillus larvae spores on adult honey bee workers to explain the death many of them in the communities affected by American foul brood disease. This work was done through two methods; first injected the microbial suspension in the intersegmental membrane of the back lymph cavity of adult bee workers. The blood films were done after 1, 2, 4&12 hrs. beginning of the injection method, while with the feeding method it carried out after one, two and three months. During the first period of the microbial injection one hour later an elongation and minor abnormalities were occurred in some blood cells. The second stage began after 2 hrs. is characterized by loss of the blood cells dye strength. After 4 hrs. the third stage is characterized by increase atrophies of some blood cells. The fourth and final stage after 24 hrs. abnormalities in most blood cells with sharp decline in their numbers clearly. This stage considers beginning end of the blood cells alive and the rapid death of most of bee workers was detected. This experiment affirms that adult bee workers can be affected by the Paenibacillus larvae spores. That may be one reason of death bee workers in infected bee colonies by the American foul brood disease.