In Egypt, the improvement of degraded soils is considered as an important issue in the agricultural security program. Large amounts of sugar industrial wastes such as sugar lime mud is producing annually causing some issues to the environment if not exploited. So, a pot trial was carried out to evaluate the influence of some soil amendments on enhancing some chemical and physical characteristics of some degraded soils of Egypt. Three soil types (saline, sandy and sodic soils) were used and treated with three soil amendments i.e. compost, agricultural gypsum and sugar beet mud which were applied to the three studied soils (two weeks before sowing) at three rates (0.5, 1 and 1.5%, equivalent to 2.5, 5 and 7.5 g pot-1 , respectively) and moisted after addition to the saturation limit. Soils were cultivated with barley. At the end of the trail, undisturbed soil samples were taken from each treatment .The findings show that barley seeds did not succeed in germination under sodic soil conditions, while seeds succeed in germination under saline and sandy soils. Generally, soil addition of all studied amendments at all rates pronouncedly improved all studied chemical and physical characteristics of saline, sandy and sodic soils compared to control treatment (without soil addition), but the improvement increased with the increase of adding rate of all soil amendments under study, where the best values were recorded due to the soil addition rate of 1.5% followed by 1% and 0.5%, respectively for all soil characteristics. Also, the results confirm that sugar beet mud as a new soil amendment in Egypt is beneficial for improving degraded soils due to its high content from organic matter and calcium.

Nowadays, degraded soils reclamation e.g., sodic soils is the main target for Egypt Government to face the great gap between food production and consumption. The high exchangeable sodium on soil colloids is a plant stress factor due to its role in reducing soil aggregates. To face this challenges, two field experiments were carried out aiming at evaluating the impact of soil amendments as main plots i.e. sugar lime mud and agricultural gypsum, and foliar application of potassium silicate at different rates [0.0 (control), 750 and 1500 mg L -1 K2SiO3] as sub-plots on wheat plants grown on soil having ESP value of 15.9%. Both soil amendments improved sodic soil properties, where the superior amendment was gypsum followed by sugar lime mud compared to untreated soil, and this improvement reflected on plant performance. The rate of 1500 mg L -1 K2SiO3 possessed the best performance, while the rate of 750 mg L -1 K2SiO3 came in the second-order and lately control treatment. Generally, the best performance of wheat plants grown under sodicity condition was realized when plants were treated with gypsum and potassium silicate at rate of 1500 mg L -1 , while the lowest performance was recorded when plants were not treated (without soil and foliar applications). The studied materials enhanced the synthesis of chlorophyll in wheat plant tissues, and this may be the reason for increasing the ability to tolerate sodicity. Also, sugar lime mud has a great opportunity to be included in the fertilization programs for degraded soil especially from an economic point of view.

In Egypt, we are under the water poverty limit. Therefore, practical solutions must be undertaken to confront the water scarcity, which hinders agricultural development in Egypt. For this purpose, two field trials were performed to assess different irrigation intervals as main plots (irrigation every 8, 10 and 12 days), soil conditioners as subplots [ without (control), biochar and compost] and foliar application of ascorbic acid at different rates (0.0, 5.0 and 10.0 mM) as sub-sub plots on maize plant performance and yield. Findings showed that deficit irrigation (irrigation every 10 and 12 days) caused a significant decline compared to irrigation every 8 days. Both soil conditioners improved plant performance and increased yield and quality of maize compared to plants grown without soil conditioners, but compost was more effective than biochar as a soil amendment in this regard. Also, the external application of ascorbic acid possessed a vital role in hindering the hazard effect of drought treatments, where plant performance and its yield increased as the rate of ascorbic acid increased. On the other hand, drought treatments led to raise antioxidants production in plant leaves at the period of 40 days from sowing to hinder the hazard effect of ROS, which were produced due to water deficit stress, while soil conditioners and foliar applications led to a decline of the maize plant's selfproduction from antioxidants.On the contrary, plants grown without studied substances cannot continue producing antioxidants under drought treatments in the advanced stage of growth (70 days from sowing).

Plants are likely to be affected by simultaneous boron (B) toxicity and salinity. Stresses on plants due to exposure to soils with high levels of naturally occurring salinity and boron, or due to irrigation with water containing high levels of salts and B can be done. For this reason, a greenhouse study was conducted at Soils Department, Faculty of Agriculture, Mansoura University in two different soils (alluvial and sandy soil) during two successive summer seasons 2013 and 2014 to determine the interactive effects of salinity and varying concentrations of boron on growth, yield and ion relations of maize (Zea mays L.var.s.c.10). The experimental design was split plot with 3 replicates. Boron and salinity were applied with irrigation water. Boron levels were 0, 1, 2 and 3 mg L-1, while salinity levels were 0.4, 2.4, 4.4, 6.4, and 8.4 dSm−1. The average values of fresh and dry weight of shoot and root yield of maize (g/pot) as well as plant height (cm) during both seasons of 2013 and 2014 increased with increasing of B levels from 0 to 1ppm under S1 treatment (0.4 dSm−1), and then significantly decreased with any increasing in boron element under all different levels of irrigation water salinity for both soils under study. On the other hand, the average values of B concentration in maize plant for both seasons significantly decreased as salinity of irrigation water increase with constant of B level but it was significantly increase with increasing of B level and constant level of salinity in irrigation water. For example, the boron concentration in shoot were 28.75, 23.0, 19.1, 13.7 and 7.8 mg/kg ,respectively using irrigation water having EC 0.4,2.4,4.4,6.4 and 8.4 dSm-1,respectively and constant B concentration of 2 ppm, while the boron concentration of maize shoot were 0.9,15.65,23.0and 26.4mg/kg, respectively at using irrigation water having EC 2.4 dSm-1 and B concentration were zero,1,2 and 3 ppm , respectively. Also, the average values of nitrogen, phosphorus, potassium, sodium, chloride and calcium contents in maize were evaluated under the effect of different levels of boron and salinity in irrigation water at the same time.

A pots experiment was executed aim to evaluate the influence of Co, Ni, Fe, Mo and B at different rates(0.0, 2.5, 5.0 and 10.0 mg L -1 )with different application methods(foliar application and soil addition)on the performance of wheat plants grown on alluvial and sandy soils.Plant performance at periods of 30 and 60 days from sowing expressed in plant height, fresh and dry weights and N, P, K content in straw as well as the nutrient status of grains (N, P, K) and other characteristics at harvest stage i.e., spike length and weight and No. of tillers plant -1 were evaluated. The superior beneficial element was Ni compared to other studied elements, while Mo came in the second-order followed by Co then Fe and lately B. All studied elements, except B, caused improve plant performance which was enhanced as the added rate of these elements increased (either with foliar or soil additions).Regarding plants received B either with foliar or soil additions, the values of all studied traits significantly increased with increasing B rate from 0.0 mg L -1 to 2.5 and 5.0 mg L -1 and then significantly decrease at 10.0 mg L -1 due to appearing B toxicity. Foliar application method was most effective than soil addition method. Performance of plants grown on alluvial soil was better than that of plants grown on sandy soil. Generally, it can be concluded that Ni may have a vital role in N fixation more than other studied elements and this was reflected on wheat plant growth.

The adequate supply of irrigation water is a crucial factor controlling the growth and productivity of crops.Under water poverty conditions in Egypt and most arid regions, sustaining the irrigation water in the root zone as long as possible becomes very necessary.Consequently, two field trials were performed aiming to evaluate the effect of zeolite soil addition of as main plots[ Z0:without zeolite(control)and Z1: with zeolite at rate of 10 Mg h -1 ]under three irrigation intervals as subplots [I1: irrigation every 12 days (traditional irrigation) in addition to irrigation every 14(I2)and 16(I3) days, which represented the deficit irrigation treatments]. The execution of the research trail was done in a split-plot design with three replicates. Maize was used as an experimental plant based on its significant response to water alterations in the root zone. Biochemical plant characters including total chlorophyll, total phenols and proline contents were measured in leaves at period of 60 days from sowing. In addition, vegetative growth parameters (plant height) as well as quantitative (e.g., No.of grain ear -1 ,No.of rows ear -1 , grain and biological yield) and qualitative (i.e.,carbohydrates, protein and oil)yield characteristics were determined at harvesting stage. Findings of this study showed that the zeolite soil addition before sowing (Z1) with irrigation interval of maize plants every14days (I2) as combined treatment realizes better results for improving quantitative and qualitative yield characteristics than non-addition of zeolite (Z0) under traditional irrigation interval (I1:every12days).Post-harvest soil analysis indicated that the usage of zeolite improves some studied soil properties e.g., bulk density, total porosity, CEC and FC.

There is a debate concerning the optimum time of phosphorus application under Egyptian soil conditions. For this purpose, a laboratory incubation experiment was carried out at Soils Department, Faculty of Agriculture, Mansoura University to determine the inorganic phosphorus forms (Olsen-P, Ca-P, Oc-P, Al-P and Fe-P) in calcareous and non-calcareous (alluvial ) soil types after different times of incubation. Phosphorus was applied at rates of 10, 20 and 30 mg / kg soil. Inorganic phosphorus forms was determined in both soils at the beginning of the experiment (at zero time of phosphorus application), and after one, two, three, four and five weeks from application. Results indicated that inorganic phosphorus forms increased with increasing phosphorus application rate. Available phosphorus form recorded the highest value after the immediate phosphorus application. Available phosphorus concentration decreased gradually over the time to reach the lowest value after the fifth week of application. On the other hand, the other precipitated phosphorus forms were increased over the time of application. Available P form was converted to unavailable P forms in the order Ca-P> Oc-P>Al-P>Fe-P. Results also showed that the fixation power of the calcareous soil was higher than the non-calcareous soil. Based on the obtained results of our experiment, it is recommended to add phosphorus fertilizers at the critical stage of phosphorus needed by plants.

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