Straw water productivity (kg/m3)

#### **Figure 5.**

*Effect of different drip irrigation systems and different saline water on wheat straw yield water productivity. SDI: surface drip irrigation; SSD-15: subsurface drip irrigation at soil depth 15 cm; SSD-25: subsurface drip irrigation at soil depth 25 cm.*

of 'Umatilla Russet' under drip irrigation in silt loam. The factors considered in the study were tape placement (one tape per row or one tape per two rows) and four soil water tension levels for automatically starting irrigation (1.5, 3.0, 4.5, and 6.0 bar). They concluded that drip tape placement had a significant effect on every variable except total marketable yield and bud-end fry color for which interactions of irrigation criteria with tape number were significant. Tape placement and irrigation criterion interacted to influence total yield, total marketable potatoes, and US No. 2 yield. Results indicated potato should be irrigated at 3.0 bar, given the silt loam soil and 2.5 mm water applied at each irrigation episode. The irrigation criterion

considered alone only influenced the total US No. 1 and over 340 g tuber weight categories. Potato cultivars were very different in their performance under drip irrigation [54].

The accumulated experience shows that seawater irrigation depends on the efficiency of the irrigation system used, and as a result of the low efficiency of irrigation uses large amounts of seawater not to allow the depletion of water until it reaches the wilt point between the irrigation because in this case the concentration of salt will be very high in the region. The soil moisture should be kept close to the field capacity at any time. This means that the efficiency of each soil should be as high as possible.

#### **3.4 Use of salt-loving plants as feed for animals**

Halophyte plants are known to be a traditional source of animal feed, although some of the problems that accompany it include high concentrations of salts, low energy content, and low animal palatability compared with traditional fodder. For the cultivation of halophytes to be economically viable, their performance should be higher or at least equal to the traditional feed. Many studies have shown that, given the lack of adequate animal feeds, especially in desert conditions, certain varieties have been successfully cultivated and can be used as feed substitutes [54, 55].

It is important to keep in mind that if halophytes are used as feed, animals may need to increase the consumption of drinking water, and feed consumption per unit may increase in animal weight as a result of increased metal content in halophytes. The carcass fed to the ingredients of a diet containing halophytes is equal to that fed on traditional feeds. One of the most common halophytes studied and used is a Salicornia cultivar. The results of the University of Arizona on sheep showed that Salicornia (seeds and market) can be used, as well as the cut as an alternative to the processed barley or the cotton seed. Salicornia is cultivated to produce oil and straw seeds. Oil can be extracted from the seed age. Organic materials that are free of salts can be used in animal feed. Oil can also be used as a high energy source in animal feed, especially poultry. Mansour et al. [44] found that subsurface drip irrigation systems may increase water use efficiency due to reduced soil and plant surface evaporation and because only the root zone or the partial root zone is irrigated as opposed to sprinkler irrigation where the entire field area is wetted. Besides this physiological dimension, several studies have been conducted for development of irrigation systems for salinity management with drip irrigation using saline water [32]. According to [20], the DI permits a uniform and frequent application of water and a direct feeding of the plant at the root zone level, leading to an increase of yield and saving water [36]. According to [47], DI improves tomato yield and reduces leaf burn (browning). However, this system may result in localized accumulation of salts at the soil surface [72] due to increased evaporation. According to [39], salt accumulates on the soil surface before migrating and reaches the root zone when DI irrigation is used. Subsurface drip irrigation has been developed to improve salinity management and water use efficiency. According to [54], SDI decreases the accumulation of salts at the root zone level of plants, producing an improved yield and fruit quality.
