The synthesis of nanomaterials is currently one of the most active in nanoscience branches; especially those help improve the human quality life. Silver nanoparticles (AgNPs) are an example of this as it is known to have inhibitory and bactericidal effects and as one of the famous metal nanomaterials in broad Sectors especially in agriculture. It was synthesized by a chemical method and characterized by UV-visible spectroscopy, TEM, and SEM in this present study. The nanoparticles were ranged between 20-50 nm and the shape seem grain with rough ends. The larvicidal activity of silver nanoparticles AgNPs were tested against the third instar larvae of housefly, M. domestica. Six concentrations were used over two different application methods (Dipping and Feeding methods) under laboratory conditions. In general, it was noticed that the larvicidal effects based on LC50 of either method against the housefly. The LC50 value for AgNPs was 45.5 mg/ml by feeding method in a different concentration (60,40,32,24,16,8 µg/ml). Data showed the moderate effect in larval mortality % and high effect of inhibition of pupation% and inhibition of adult emergence%. Furthermore, the treatment caused some morphological effects such; abnormalities of larvae and pupae, larval pupal intermediates, deformed adult with crumpled wings. Also, some adults couldn't emerge and remained in their puparia.

Two field experiments were carried out at sakha experimental station during 2004/ 2005 and 2005/2006 seasons to investigate the effect of different sowing methods (dry method and dry method after false irrigation) and some herbicides i.e. glyphosate, butralin, imidazolin, bentazon, propyzamide and hand combing treatment on controlling dodder weed Cuscuta planiflora and growth of clover plants Trifolium alexandrinum L. Results indicated that the hand combing treatment and different sowing methods were not enough in dodder control, but it used only as a help factor in control program. Also, the results indicated that butralin herbicide showed good control of dodder under the sowing after false irrigation, followed by propyzamide, glyphosate, imidazolin and bentazon treatments. Also, showed that the parasitic weed dodder caused a great reduction in fresh weight of clover plants. Clover plants infected with dodder showed that the lowest contents of chlorophyll a, b and total chlorophyll compared with healthy plants. Data also cleared that all tested herbicides showed least effective on chlorophyll content. Also, showed the that the reduction percentage of chorophyll content was increased by increasing the time of treatment.

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Three strains of Streptomyces rimosus were grown on four different media. The one suitable for the production of oxytetracycline by Streptomyces rimosus 12907 was modified by black strap molasses, fodder yeast (40% total protein) and rice bran. The volume of the fermentation medium was sealed up in a 1200-litre fermentor aerated with sterile air obtained from a system used in the purification of air. 850 g crude oxytetracycline was obtained when the fermented medium (700 litres) was extracted with 1-butanol.