Background: Phosphorus is one of the essential nutrients required for plant growth. Although it is moderately available in nature, it is a deficient nutrient in most soils especially calcareous soils. Phosphate rock (PR) is considered the cheapest P fertilizer. Phosphate rock sources may be of igneous or sedimentary origin. Results: In Egypt, the natural phosphate rock is located in Sebaiya (Nile Valley), Safaga (Red Sea), and Abu Tartur (Western Desert). The higher the organic matter contents in soil, the better dissolution of the PR. Legumes are particularly suited for the use of PR. Biological solubilization of phosphate rock is more environmentally friendly than acidulation. Fungi are widely used as producers of organic acids, and particularly, some Aspergillus and Penicillium species have been directly introduced into the soil in order to solubilize the phosphate rock. Biological solubilization will make phosphorous available for plant use with minimum pollution to the environment. Phosphate rock inoculated with bacteria and Mycrrohizae proved to be a suitable approach to use PR for continuous crop production. Conclusion: The amendments such as elemental sulphur, compost, organic manure, and plant waste could be applied to PR to improve crop cultivation under Egyptian soil conditions.

Faba bean (Vicia faba L. var. Nobaria 12) was grown under saline irrigation water (1.0% Sea salt EC iw = 15.2dS m -1 ) and none saline water (Control, EC iw = 0.64dS m -1) and subjected to soil application of calcium (0,100 and 200ppm Ca as Calcium hydroxide) and foliar application of boron (0, 5 and 10ppm as boric acid). Results indicated that the reduction in growth and yield was found proportional with increasing salinity of irrigation water at all studied parameters but application of calcium and boron minimized the deleterious effects of salinity up to various extents. The significant improvement was observed in the shoot and root weight, chlorophyll content of leaves, due to the application of 200ppm calcium combined with foliar application of 5ppm boron under both non saline and saline conditions of irrigation water. Also, Pod and seed yield was increased as affected by Ca and B application under both saline and none saline irrigation water. In general, K + /Na + and Ca 2+ /Na + ratios of faba bean shoot was lower under saline irrigation water condition as compare to none saline water. Foliar spray of Boron at 5ppm was found much effective to minimize K + /Na + and Ca 2+ /Na + ratios and alleviating salinity hazard. Excess of Boron caused deleterious effects on plant growth indicating Boron toxicity at 10ppm B applied as foliar application.

Salt stress is one of the major abiotic stresses decreasing crop production, particularly in dry and semi–arid regions. Reclamation of salt–damaged soil is important as it is sweeping cultivable land day by day. Potassium is an essential element for plant development which is an extremely active ion in the soil system. Potassium is second to nitrogen in plant tissue levels ranging from 1 to 3% by weight. As a cation, potassium is highly mobile in plant and moderately mobile in the soil system. The essentiality of potassium is identified with its multiple roles in plants. Among these are the maintenance of cell turgor pressure and cell lengthening, osmoregulation, leaf and stomata movements, enzyme activation, phloem solute transport, cation/anion balancing, control of membrane polarization, cytoplasmic pH regulation, chloroplast structure and functioning, protein and starch synthesis, and energy preservation across membranes. As almost all of these processes are directly associated to plant adaptation to the in hospitable environment. It could be concluded that potassium uptake, transportation, and homeostasis play important role in conferring salt tolerance in plants.

The aim of this research was to assess the influence of saline irrigation water which prepared to obtain salt stress of 0.

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