Soil salinity problems in arid and semiarid areas are very common due to low rainfall, high evapotranspiration and poor water management. Among different factors for low agricultural production in developing countries like Pakistan, the foremost problem is to get sufficient water of good quality at desire place at right time. In Pakistan canal irrigation water available at watercourse head is very low than crops irrigation water requirements. Underground water is used as additional source of water to fulfill crop irrigation needs, while most of our tube well water is not fit for irrigation purpose. The application of such poor quality water deteriorates soil properties and ultimately decreased crop yields and quality. The ultimate objective should be to maximize the supply of irrigation water for agricultural production and the use of poor quality water will increased the area under cultivations. The poor quality water can be used with soil amendments to enhance crop productions and to maintain soil health. An alternative approach is to develop and select salt tolerant cultivar that can be grown successfully under poor quality water irrigation. Keeping above facts in view hydroponics culture and lysimeters experiments were conducted; (1) to determine salt tolerance of some newly approved and candidate cultivars of maize and wheat on the basis of gas exchange, growth and ionic attributes under saline and saline sodic solution culture; (2) to study the influence of organic manure and gypsum amendment on macro and micro-nutrients uptake in wheat grain and maize fodder under water induced salt stress; (3) to study the relationship of plant gas exchange attributes with plant ionic composition, water use efficiency and mineral nutrients uptake; (4) to evaluate the effect of irrigation water varying in EC and SAR on soil salt load, plant leaf stomatal conductance, photosynthetic and transpiration rates. The results depicted that wheat cultivars, SARC-1, V-07096, V-05082, SARC-7 and Pasban-90 showed less reduction in plant photosynthetic rate, dry biomass production, K+: Na+ and C2+: Na+ ratio than V-05003, V- 07076 and V-07194. While in maize cultivars the highest reduction in plant photosynthetic rate, K+: Na+ and plant dry biomass were recorded in Sadaf, FH-963, FH-722 and FH-793 and the minimal in Sahiwal-2002 and Afgoi. Salt tolerant cultivars uptake less Na+ which depicted that Na+ ion exclusion is positively correlated with salt tolerance and plant biomass production. Subsequently, growth and yield response of selected salt tolerant and sensitive 2 cultivars of maize and wheat crops were evaluated in soil culture. Farmyard manure and gypsum were incorporated in soil to investigate their mitigating effects on soil and crops under saline and saline sodic water treatments. Irrigation with saline-sodic water to maize and wheat crops revealed that salt tolerant cultivar, Sahiwal-2002 and V-07096 maintained lower Na+ concentration in leaf sap and higher K+, Ca2+ and K+: Na+ ratio as compared to salt sensitive cultivars, Sadaf and V-05003. From the results it is concluded that farmyard manure and gypsum application partially offset the harmful effects of poor quality water, improved maize fodder and wheat grain yield, plant photosynthetic rate, water use efficiency, membrane stability index, K+: Na+ and mineral nutrients uptake as compared to sole poor quality water application. Organic manure and gypsum addition in soil enhanced the volume of leachates and caused a considerable reduction in soil salt load, soil SAR and improved mineral nutrients uptake. Key words: Poor quality water, K+: Na+, PCA, photosynthetic rate, salt load