الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Egypt is suffering from a great shortage in edible oils, so the Egyptian government is pressing hard to close the vast gap between production and consumption of edible oil.
Sunflower (Helianthus annuus L) is one of the main oil crops suggested to cover the increasing demand for edible oils in the country due to its adaptability to environmental condition and the high oil content in its seed up to50%.Furthermore, sunflower oil has high content of unsaturated fatty acids and vitamin E. Moreover, its cake contains 25 – 35 % of protein which is mostly fed to livestock due to its high biological value.
Water stress is one of the sever conditions that affect crop productivity. Water being an integral part of plant, plays a vital role in the maintenance of plant life. The deficiency of water modifies soil-plant water relationship by lowering tissue water potential and impairing metabolic processes, (Akhtar et al 1993). Currently, water is a primary limiting factor in Egyptian agriculture and it is important to address our efforts to the fundamental issue of increasing crops production while reducing their water consumption especially in the reclaimed lands. This can be achieved through an effective use of modern irrigation techniques.
Sunflower cultivars markedly differ in their growth characteristics and potential yield. Several investigators under Egyptian conditions confirmed this fact.
Nitrogen plays an important role in plant growth and is considered as an indispensable element for several vital functions and needed for maximum yield in most field crops. It is well known that continue use and overuse of chemical fertilizers have caused soil pollution, agricultural and health consequences. Numerous efforts are being exercised everywhere to combat the adverse consequences of chemical farming by using alternative sources, which are environment friendly plant nutrients. In recent years, biofertilizers have emerged as a promising component of integrating nutrient supply system in agriculture. Our whole system depends on many important ways, on tremendous activities and there appear to be a tremendous potential for making use of microorganisms in increasing crop production (Bloemberg et al 2000). However, chemical fertilizers should applied alongside biofertilizers in suitable combination (Chowdhury and Mukherjee 2006). These methods of fertilizers aim to minimize chemical fertilizer application, reduce the production costs as well as environmental pollution which can occur by the excessive use of chemical fertilizers.
This investigation was carried out to study the effect of water intervals and biofertilizers in two sunflower cultivars on vegetative growth and productivity.