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Abstract Two field experiments were carried out during the summer season of 2011 and 2012 at the Experimental Farm of the Faculty of Agriculture, Menoufia University, Shebin El-Kom to study the effect of irrigation regimes and irrigation with magnetic or non-magnetic water, along with their interactions on growth, relative water content, chemical composition, podsquality, as well as, yield and its components. The design of this experiment was split plot design with three replicates. 1. Water regimes were applied where the as plants were irrigated by 20, 30, 40, 50 and 60% of the field capacity. 2. Irrigation with magnetic water and irrigation withnon- magnetic one. 3. The interactions effect between water regimes and magnetic or nonmagnetic water were alsostudied. The results of this experiment can be summarized as follows: 1.Soil salinity. Data show clearly that soil salinity, measured as EC (dsm-1) after harvesting, was decreased at different soil depths with irrigation bean plants by magnetized water. So, all values of relative changes of EC as a precent of original soil EC values were negative and were more negatively with magnetized water. Soil salinity measured as EC(dsm-1) was also strongly influenced by soil moisture regimes. Thus, increasing soil moisture up to the maximum level, i.e., 60% of the field capacitycaused a little decrease of soil EC (dsm1). Little decrease of soil EC (dsm1) was induced with the increase of soil moisture content. 2. Available N,P and K. In all soil depths, irrigation bean plants using magnetic water resulted in a clear increase of soil content of available N,P and K, where the high increase was found in the top soil layer.Irrigation regimes resulted in an increase of soil available N,P and k contents (mg/Kg-1 ) in all soil layers. The high contents of available N,P and K were found in the surface layers (0-15 and 15-30 cm) when bean plants were irrigated at 60% of the field capacity. Increasing soil moisture up to the maximum level, i.e., 60% of the field capacity increased N,P and K contents. 3.Vegetative growth characters. Plant height, number of leaves and leaf area (cm2/plant) in bean plants were influenced by magnetic water application. The obtained data reported that a significant increase in plant height, number of leaves and leaf area/plant when bean plants were irrigated by magnetic water compared with non-magnetic one. Significant increase were found also in root fresh and dry weight and total plant fresh and dry weights as a result of irrigation with magnetic water. The calculation values of total and individualfresh and dry weights show variations for these parameters to the magnetized or nonmagnetized water in the two growing seasons. Plant height, number of leaves, leaf area (cm2/plant), root fresh and dry weights as well as whole plant fresh and dry weights of bean plants were increased with increasing soil moisture. Thus, application of 60% of soil moisture content gave the highest growth parameters of bean plants.Meanwhile, decreasing soil moisture to 20% of the field capacity achieved the lowest values of plant growth characters, in both seasons. Plant growth characters,i.e., plant height, number of leaves, leaf area, root fresh and dry weights and total plant fresh and dry weight were significantly affected by the interactions between magnetic water and irrigation regimes. The highest values of all plant growth parameters were obtainedwhen bean plants were irrigated by magnetic water under the highest level of soil moisture i.e., 60% of the field capacity and the lowest values in this respect were found due to the interactions between nonmagnetic water irrigation and the low level of water regimes (20% of the field capacity). 4.Growth analysis attributes. Irrigation bean plants by magnetized water cause a significant effect on growth analysis attributes i.e., leaf area index(LAI), relative growth rates (RGR), and net assimilation rates (NAR). The previous charactersand harvest index(HI) were significantly increased by irrigation plants with magnetic water as compared with non-magnetic one. In general, increasing soil moisture content up to the maximumlevel of the field capacity (60% F.C) increased leaf area index, relative growth rate, and net assimilation rate, in both growing seasons. Thus, the highest values of LAI, RGR and NAR were obtained with irrigation bean plants at 60% of the field capacity, while irrigation at 20% of the field capacity decreased LAI, RGR, and NAR rates. The interactions between the two studied factorssignificantly affected leaf area index (LAI), relative growth rate (RGR) and net assimilation rate (NAR) and harvest index (HI). The highest values of LAI, RGR and NAR were obtained under the combinations of irrigation plants by magnetic water at the high level of soil moisture content (60% of the field capacity). 5.Plant chemical compositions. 5.1. Photosynthetic pigments (Chl.a, b and carotenoids): The concentrations of photosynthetic pigments ,i.e.,chlorophyll a, b, carotenoids and total chlorophyll in bean leaves showed a significant increase when plants were irrigated with magnetic water as compared with non-magnetic one. Regarding the influence of irrigation regimes on the concentrations of photosynthetic pigments,i.e. chlorophyll a,b, carotenoids and total chlorophyll in the leaves, the results showed a significant variation due to the different soil moisture contents.The concentration of photosynthetic pigments in leaves was significantly affected by the combinations between magnetized water treatment and soil moisture contents. The highest values of these parameters were obtained when bean plants were irrigated by magnetic water at 20% of the field capacity. Whereas, the lowest values in thisrespect were obtained when plants were irrigated by ordinary water at 60% of the field capacity. 5.2. Sugars and total carbohydrates in plant leaves. Irrigation plants by magnetic water significantlyincreased each of total carbohydrates and total sugars content in the leaves as compared to non- magnetic water. With regard to the effect of different irrigation regimes on total carbohydrates and total sugars, these biochemical components were significantly increased by increasing irrigation levels up to the maximum level of soil moisture i.e. irrigation at 60% of the field capacity. On the other hand, the minimum irrigation level, i.e. 20% of the field capacity, produced the lowest contents of total carbohydrates and total sugars in the leaves. As to the interactions, the highest values of total carbohydrates and total sugars content in bean leaves were obtained under the highest level of water regimes i.e. irrigation plants at 60% of the field capacity with magnetic water, whereasthe lowest values of these chemical contents were achieved when bean plants were irrigated at 20% of the field capacity by non- magnetic water. 5.3. The contents of macronutrients, nitrogen, phosphorus and potassium percentages. With respect to theconcentrations of N, P and K (%) contents and its uptake (mg/plant), irrigation bean plants by magnetic water significantly increased both contentsand uptake of nitrogen, phosphorus and potassium. Increasing soil moisture content from 20% of the field capacity to 60% caused a significant increase in the concentrations of N,P and K% inbean leaves. Nitrogen, phosphorus and potassium uptake (mg/plant) of bean plants were also responded to different irrigation regimes. Respecting to the interactions effect,the concentrationsof N,P and K% and their uptake (mg/plant) by bean plants were significantly affected by irrigation plants with magnetic water under the different soil content.Irrigation bean plants by magnetic water at 60% of the field capacity gave the highest values of nitrogen, phosphorus and potassium concentrations in the leaves.However, the highest value of N,P and K uptake (mg/plant) was obtained by irrigation plants with magnetic water at 50% of the field capacity. 5.4. Protein content in bean dry seeds. The crude protein in seed of plants which irrigated with magnetic water was significantlyincreased compared with that found under irrigation by non-magnetic water. Increasing soil moisture content up to the highest level i.e. irrigation at 60% of the field capacity increased the crude protein content in bean dry seeds. Respecting to the interactions effect, the highest values of crude protein in dry seeds was 23.13 and 24.43% by irrigation beanplants with magnetic water at 50 or 60% of the field capacity, in the first and the second seasons, respectively. While the lowest values of crude protein content (15.31 and 16.06%) in the frist and the second seasons, respectively were found by irrigation plants with non-magnetized water at 20% of the field capacity. 5.5. Relative total, bound and free water contents in leaves. Irrigation plants with magnetic water increased total and free water contents in leaves as compared to non-magnetic one.In addition, different levels of soil moisture, led to a significant increase in each of total, bound and free water contents. The previous characters were increased with increasing the amount of water supply. Regarding to the interactions effect of water types and water irrigation regimes on water contents in bean leaves, results revealed that the highest values of total and free water were obtained due to the interactions of irrigation bean plants by magnetic water at the highest level of water supply i.e. 60% of the field capacity. 6. Flowering and fruit setting percentage: Irrigation plant with magnetic water led to a significant increase in number of flowers per plant and fruit setting percentage as compared with irrigation by non- magnetic water. Number of flowers per plant increased by increasing the levels of soil water supply. Number of flowers/plant and percentage of fruit setting were significantly influenced by the interactions between irrigation by magnetic and water regimes at 60% of the field capacity. 7. Yield of dry seeds and its components. Number of pods/plant, seed yield per plant (gm/plant), weight of 100 dry seeds (gm) and total yield of dry seeds (Kg/ feddan) of bean were significantly affected by irrigation with magnetic watercompared with irrigation by non-magnetic water. With regard to the effect of water regimes on number of pods/plant, seeds yield/plant, weight of 100 seeds and total yield, data show that the yield and its components gradually and significantlyincreased with increasing water supply at 60% of the field capacity. The interactions between the previous factors caused a significant effect on number of pods/plant, seed yield per plant, weight of 100 seeds and total yield/feddan.The highest value of number of pod/plant wasobtained by irrigation with magnetic water at 60% of the field capacity, while irrigation plants at 20% of the field capacity by non- magnetic water produced the lowest value in this character.However, the highest values of weight of 100 seeds, yield/plant and total yield/feddan were obtained when bean plants were irrigated by magnetic water at 50% of the field capacity as compared with the other treatments. On the other hand, irrigation bean plants by non-magnetic water at 20% of the field capacity gave the lowest values of seed yield. 8. Water use efficiency. Water use effiency was significantlyincreased by irrigation bean plants with magnetic water compared with irrigation plants by nonmagnetic water. The greatest value of water use efficiency was obtained by irrigation bean plants at 50% of the field capacity compared to irrigation at 20,30,40 and 60% of the field capacity. The highest values of water use efficiency was obtained in plants irrigated by magnetized water at 50% of the field capacity, while irrigation plants by non- magnetic water at 20% of the field capacity achieved the lowest value of water use efficiency |