Impact of Magnetization and Organic Acids on the Growth and Productivity of ‘Washington Navel Orange’ Trees under Irrigation with Salty Water

Abstract

The current investigation was executed to assess the effects of magnetization, which combines magnetized water (MW) and magnetic iron (150g tree -1 ), and organic acids (Humic acid at 150cm tree -1 ) As anti-salinity factors in mitigating the negative effects of salinity on growth, leaf mineral contents, yield and fruit properties of Washington Navel orange trees planted in sandy soil and watered with drip irrigation method (ECw of irrigation water = 4ds/m) in 2014 and 2015 under El-Behera governorate conditions. The results indicated that the trees subjected to combination treatment involved (MW) and humic acid as soil application or magnetic iron gave the best vegetative growth parameters (tree height, canopy volume, No. of shoots per branch, shoot length, No. of leaves shoot and leaf area compared to comparative treatment (the control). Soil application of humic acid under irrigation with MW(MW+ Humic acid) increased mineral contents for leaves (N, P, K, and Mg) meanwhile, the sequence of MW+ magnetic iron gave the highest Ca content. The highest leaf Na content (0.48 and 0.52%) obtained by the control meanwhile, the lowest leaf proline content (10.0 and 9.2mg g -1 ) was obtained by combination treatment (MW + humic acid) compared to the highest values (12.4 and 12.7mg g -1 ) recorded with the control (WW). Yield and fruit quality attributes were increased with soil application of humic acid or magnetic iron following irrigation with magnetized water.

Magnetic Iron–Improved Growth, Leaf Chemical Content, Yield, and Fruit Quality of Chinese Mandarin Trees Grown under Soil Salinity Stress

“…Magnetic iron at a concentration of 750 g.tree −1 achieved the highest values in comparison to those of other treatments. The stimulatory result of magnetic iron on fruit juice volume reported in this study is incompatible with El-Dengawy et al [ 40 ], who stated that magnetic iron treatments significantly increased fruit weight and volume of ‘Washington’ navel orange fruits when compared with that of untreated trees. The same applies to Ennab [ 6 ] and Mohamed et al [ 36 ] for mandarin trees.…”

“…On the other hand, the lowest percentage of vitamin C in fruits was recorded when mandarin trees received no treatment (control). These results are supported with the previous study of El-Dengawy et al [ 40 ], who found that magnetic iron treatments significantly increased vitamin C in ‘Washington’ navel orange fruits. The increase in vitamin C (Ascorbic acid mg/100 mL of fruit juice) in fruit juice at harvest time might be due to the increase in weight of the fruit and the increase in the parameters of vegetative growth, such as shoot length and leaf area, caused by magnetic iron treatment; it also may be due to irrigation with magnetized water, causing a significant increase in the activities of the antioxidant enzymes over the control plants [ 48 ].…”

“…Magnetic iron application significantly increased yield and improved element uptake in the root area profile [ 17 ]. The increase in yield might be due to the increase in retained fruit percentage, improved nutritional status, and subsequent appropriate vegetative growth of the treated navel orange trees [ 40 ]. Moreover, magnetic iron plays a beneficial role in the assimilation and absorption of nutrients, which raises fruit quality and yield [ 29 ].…”

“…mango in comparison to that of untreated trees. Likewise, El-Dengawy et al [ 40 ] stated that magnetic iron treatments significantly increased the TSS% of ‘Washington’ navel orange fruits when compared to the untreated trees. The increase in TSS percentage might be due to increasing ion mobility and ion uptake of magnetic iron treatments, which also leads to better photosynthesis stimulation in plants and an improvement of fruit characteristics [ 15 ].…”

“…These results are in line with the findings of Mohamed et al [ 41 ], who stated that the TSS/acid ratio of Balady mandarin fruit juice increased by magnetic iron treatments at concentrations of 500 and 750 g.tree −1 compared to that of the control. Similarly, El-Dengawy et al [ 40 ] stated that magnetic iron treatments significantly increased the TSS/acid ratio of ‘Washington’ navel orange fruits. However, the total acidity (%) of fruits decreased in comparison with that of the control; see Figure 6 B.…”