This study was carried out to investigate the effect of saline water irrigation at 2000, 4000, 6000, 8000 and 10000 ppm by using a mixture of two salts (sodium chloride: calcium chloride, 2:1, w/w)  in addition to tap water  as control and foliar sprayings of Salicylic acid (SA) at 100, 200 and 300 ppm in addition to tap water as control on growth, flowering and chemical composition of pot marigold plants in the two successive seasons of 2014/2015 and 2015/2016 in the Faculty of Agriculture, Ain Shams University, Qalyubia Governorate, Egypt. Results revealed that all tested foliar applications of SA increased all vegetative growth characteristics (plant height, number of leaves /plant, leaf area, number of branches/plant, diameter of stem, fresh and dry weights of vegetative growth and roots, and roots volume), and flowering attributes (number of inflorescences/plant, diameter of inflorescence, fresh and dry weights of inflorescences). While, saline water irrigation decreased growth, flowering parameters, chlorophyll, carotene contents in flowers and some minerals contents of the vegetative growth, i.e. nitrogen, phosphorus and potassium percentages. However, saline water irrigation increased proline and some mineral contents, i.e. calcium, sodium and chloride percentages of the vegetative growth. In most cases, under the same saline water irrigation conditions spraying SA at 100 and 200 ppm concentrations alleviated the salinity effect on the plants, enhanced the plant growth and increased the flowering parameters. The most effective treatments which enhance growth, flowering parameters, chlorophyll content, carotene contents in flowers, proline and mineral contents were found to be 100 and 200 ppm SA spraying under nonsaline conditions.

A greenhouse pot experiment was carried out to investigate the effect of salinity and potassium at different levels alone or in various combinations on growth, mineral and proline content in leaves of plantlets of Phoenix dactylifera L. cv. Bartomouda (in vitro production, two years old from acclimatized them). The following treatments were applied: three levels of salinity Na Cl + Ca Cl2 w.w 2:1 (14000, 16000 and 18000 ppm.) and two levels of potassium (2000 and 3000 ppm) in addition to control (no salts or potassium used), salts and potassium were added in the irrigation water. In general, all levels of salinity significantly decreased various growth parameters such as plant height, number of leaves and roots, root length, fresh and dry weights of leaves than that of the control. These parameters were decreased with increasing salinity levels, whereas it, significantly increased Na, Ca and K contents in leaves with high content of proline. The treatment 18000 ppm salts gave the highest significant reduction of the growth parameters, while caused an increase in proline Na, Ca, and K contents compared to control treatment (no salts) . This was true in both seasons. The applications of potassium significantly increased the previous growth parameters as compared with the control treatment (without salts and potassium) the treatment 3000 ppm had the highest results. Moreover the applications of potassium gave high alleviated the negative effects of salt stress, the treatment 3000 ppm gave the best results on the growth parameters of date palm plantlets grown under salinity condition . Regarding the interaction the obtained data revealed that the interaction between treatment 3000 ppm potassium and 14000 salts produced the highest significant results. Generally, from the obtained results it can conclude that the plantlets of date palm produced by tissue culture can be tolerated salt stress by addition of potassium which can significantly ameliorate the harmful effects of salts, positive effects on the growth parameters of the plantlets was showed by potassium applications.

Two pot experiments were carried out during the summer seasons of 2006 and 2007 to investigate the effect of irrigation with diluted saline water; i.e., 10, 30 and 50% in addition to Tap water as a control on growth, chemical composition, yield and tuber quality of three new sweet potato cultivars (Minufiya 6/96, Minufiya 2/96 and Minufiya 171/96) as well as the local cultivar (Mabrouka). The obtained results revealed that, saline water at 10 and 30% levels stimulated growth of sweet potato plants represented by plant height, number of leaves and branches, dry weight of shoots as well as the contents of photosynthetic pigments, proline, total carbohydrates, N, P, K+ and Ca++ in sweet potato leaves were also increased. Moreover, total water content (TWC), bound water (BW), bound / free water ratio (BW/FW) and relative water content (RWC) increased under these conditions. All these parameters decreased at the level of 50% salinity. Yield and its quality significantly increased at saline water at 10% level. Also, chemical composition of tuber roots; i.e., total carbohydrates, soluble sugars, carotene, starch and dry matter contents were enhanced under these conditions. All previous parameters decreased with increasing saline water up to 50%. Saline water levels increased Na+ content in the leaves. As for the tested cultivars, generally Minufiya 6/96 had the best growth and yield, was more stable in the chemical components and its roots had the highest nutrients value under the control and salt stress conditions, followed by Minufiya 2/96 then Minufiya 171/96. The tuber roots yield of Mabrouka cultivar was completely depressed at 30 and 50% salinity levels. As for interaction between cultivars and salinity levels. The highest level of salinity (50%) lead to a significant decrease in all growth parameters, RWC, TWC, bound water (BW), bound water / free water (BW/FW), chemical composition, yield and its quality in all new tested cultivars. While, Mabrouka cultivar showed a significant decrease in these parameters under the all salinity levels. Accordingly, Minufiya 6/96 was the highest tolerant to the tested salinity stress, followed by Minufiya 2/96 and Minufiya 171/96. On the other hand, Mabrouka cultivar sensitive to salinity.