The effect of different concentrations of ascorbate (As) at 0, 0.25, 0.5 and 1.0 mM, salicylate (Sa) at 0, 0.25, 0.5 and 1.0 mM , in addition to silicate (Si) at 0, 100, 250, and 500 ppm on potato plant subjected to different water regimes; three days interval (control), four days interval (4DI) and five days interval (5DI).  Photosynthetic pigments, free proline and malonyldialdehyde (MDA) concentrations, and plant dry matter percentage were determined. Also, tuber yield was recorded and the percentage of tuber dry matter was determined. Water deficit resulted in significant reduction in tuber yield, plant dry matter percentage beside significant increase in free proline and MDA contents. Meanwhile, effects on photosynthetic pigments content and tuber dry matter were inconsistent. The effects of using different concentrations of ascorbate (As) under water deficit provide a superior effect of As at 0.25 mM. Data revealed that ascorbate treatment enhanced tuber yield by improved Chl (a and b) and carotenoids content, with a promoted reduction in free proline content and MDA. Salicylate (Sa) treatment under water deficit exhibited partial enhancement in photosynthetic pigments; where, Sa (1.0 mM) increased Chl a under all water regimes and Chl b at control and 4DI water regimes. While Sa (0.5 mM) improved carotenoids content at 5DI water regimes. The positive effect of salicylate on tuber yield was obvious only at 5DI water regime; as salicylate concentrations (0.25, 0.5 and 1.0 mM) enhanced tuber yield by 65.61, 21.8 and 33.33%. Data exhibited that these increments were concomitant with a  reduction in free proline content and a slight increase in tuber dry matter. Interactive effects of Silicate (Si)/water deficit were variable with the concentration under the used water deficit regimes, where, Si (100 ppm), showed higher means of Chl (a and b) with a reduction in free proline contents, at both 4DI and 5DI. The higher tuber yield resulted only at 5DI. More pronounced effect, Si (250 ppm) exhibited increment of photosynthetic pigments, plant dry matter, tuber yield, along with slight reduction in MDA, particularly at 5DI. It could be concluded that silicate treatment alleviated water stress by improving carotenoids content, plant dry matter and reducing both free proline and MDA contents, which attributes enhancement in tuber yield under water deficit. Generally, lower concentrations of As, Sa and Si showed their benefits under higher water stress regimes.

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 acclima tized them). The following treatments were applied: three levels of salinity Na Cl + Ca C12 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 potas sium 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. Gen erally, 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.

Steroid hormones (H) and tetracycline antibiotics (T) are considered two important classes of veterinary therapeutic agents administrated to livestock for different purposes that have been detected for many environmental matrices in wide concentrations range. The effect of progesterone (Pro), androstenedione (4-AD), androstadienedione (1,4-AD) and tetracycline antibiotics namely oxytetracycline (OTC), chlortetracycline (CTC) and tetracycline (TC) on arugula plants (Eruca sativa) growth and biochemical composition was investigated. Compost and potassium permanganate were applied to minimizing the negative effect of veterinary therapeutic agentson plant. A pot experiment was conducted at the greenhouse of Agricultural Research Center (ARC) at Giza Governorate, Egypt. Soil fortified with 2 mg kg-1 of H and Ttarget compounds individually and combined was used to study their effect on chlorophyll, proline, catalase (CAT), and peroxidase (POD) activities as antioxidant enzyme and plant growth. Under this experiment conditions; the obtained results showed that veterinary therapeutic agents caused increased the content of proline, however chlorophyll content was increased as a result of H application and decreased with T application. Both CAT and POD activities were increased, especially with the combined mixture application. Potassium permanganate or compost can be used for remediation procedures in veterinary therapeutic agentscontaminated soils.

This study was carried out in two successive seasons (2014-2015 and 2015-2016) at SEKEM company Farm (Bilbase, Sharkya Governorate) on chia (Salvia hispanica) plant which is  a new crop introduced lately to Egyptian cultivation as  a medicinal plant. The effect of three irrigation levels of different reference evapotranspiration (80, 100 and 120 % ETo) with foliar application of three levels of proline (100, 200 and 300 ppm), salicylic acid (200, 400 and 600 ppm) and putrescine (10, 15 and 20 ppm) in addition to the control treatment (tap water) was investigated on growth and yield of Salvia hispanica cultivated in sandy loam soil with drip irrigation system. The results of the two years experiments indicated that the highest values of plant growth parameters and seeds yield of S. hispanica were obtained from 100 % ETo. While 120 % ETo resulted in the maximum value of roots fresh and dry weights. Foliar-spray application of proline (100 ppm.), salicylic acid (200 ppm) and putrescine (10 ppm) resulted in optimum fresh and dry weights of herbage and roots. Seed yield was higher in plants sprayed with proline (100 ppm) and putrescine (10 ppm), although the differences between them and salicylic acid (200 and 400 ppm) or putrescine (15 ppm) were insignificant in both seasons. This leads us to recommend irrigation of S. hispanica accordingly with 100 % ETo coupled with foliar-spray application of salicylic acid (200 ppm) from the economic point of view.

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.