Optimizing Irrigation Rates and Antioxidant Foliar Spray Effects on Growth, Yield, and Fruit Quality of Manfalouty Pomegranate Trees

Abstract

This study aims to identify the most effective irrigation rates for Manfalouty pomegranate trees to enhance their growth, yield, bioactive compound content, and fruit quality. Additionally, the research evaluates the effects of foliar spray applications of glycine, ascorbic acid, and riboflavin on the physiological responses of the trees. Morphological, physiological impacts, and fruit quality treatments were analyzed using Pearson correlation and cluster analysis. As irrigation levels were reduced up to 60%, all vegetative characters demonstrated a significant drop. Glycine treatment enhanced yielding shoot lengths, leaf area, and leaf number. Among the key findings was that there were no appreciable variations between 100% ETc and 80% ETc with riboflavin or glycine spraying for leaves total chlorophyll. Leaves treated with glycine, ascorbic acid, and riboflavin spraying had higher levels of total antioxidants, total phenols, and total flavonoids, while glycine gives the highest results and enhanced the antioxidant system of pomegranate leaves. Reducing irrigation from 100% to 60% ETc in both seasons, respectively, resulted in a progressive decrease in yield (ton/fed.), and fruit creaking (%); this effect was overcome using the glycine foliar spraying. The results also demonstrated that all spray treatments reduced the cracking rate, with the glycine spray treatment being the most effective in this respect that enhanced also fruit length, fruit diameter, fruit weight, and arils weight %, total soluble solids, total sugar, anthocyanin, vitamin C, and the antioxidant contents. The findings provide valuable insights for sustainable pomegranate cultivation practices that maximize productivity and quality while maintaining plant health using low irrigation and glycine as foliar sprayer.

1. Introduction

Water is a vital resource for agriculture, but in arid areas, the availability of fresh water supplies is limited, which reduces agricultural productivity. Egypt, one of the most water-stressed nations, is further burdened by urbanization, industrialization, and population expansion [1,2]. It is crucial to maintain agriculture while safeguarding water resources. About 94% of Egypt’s sustainable water supply comes from the Nile River; however, worries regarding future water availability and possible decreases in Egypt’s water share are raised by the Grand Ethiopian Renaissance Dam’s construction [3]. For agricultural planning and irrigation project design, figuring out how much water is needed for crop irrigation is essential [4]. With a sizable, planted area, Egypt is classified as a major pomegranate producer and exporter in the region [5]. Pomegranates can tolerate a certain amount of drought, but for best growth, output, and fruit quality—especially in arid and semiarid regions—regular irrigation is required. Because of its adaptability to many climatic circumstances, the pomegranate is a fascinating option for growing in desert areas [6]. Pomegranates have a remarkable nutritional and medicinal properties, which makes the demand for it increasing due to its entry into the medical industries, cosmetics, nutraceuticals, and even in functional foods [7]. Pomegranate characterized with various antioxidant types can be utilized to treat human conditions like arthritis, cardiovascular illness, and neurodegenerative problems [8,9]. It has unique secondary metabolites, including bioactive chemicals, vitamins, antioxidants, and polyphenolic substances [10]. Nutritional metabolism, photosynthesis, ion absorption and translocation, carbohydrate metabolism, respiration, and chlorophyll production are just a few of the advantages that these secondary metabolites offer [11]. These metabolites also protect the plant against reactive oxygen species (ROS), preserve the photosynthetic process, and protect the cells from harm and death [2].

In response to stresses, such as drought, plants create osmolytes (osmo-protectants), to prevent dehydration of their cellular machinery; these compounds include glycine, sugars, phenolics, and proline [10,12]. Glycine is a quaternary ammonium material that stabilizes cellular protein complexes and plant cell enzymes, preserves cellular membrane integrity, and also improves nutrient solubility [13]. Exogenous applications of glycine were found to enhance leaf chlorophyll and the plant growth traits [14]. Moreover, exogenous applications of glycine can improve fruit growth, quality, fruit yield, and even the plant biochemical characteristics as demonstrated by Mosa et al. [15] in Flame seedless grape, Abd El-wahab and Shakweer [16] in “Le-Conte” pear trees, Almutairi et al. [17] in Psidium guajava trees, Mhmood and Alhayany [18] in Yemeni pomegranate transplants, and Abo-Ogiala [19] in wonderful pomegranate trees.

Other unique antioxidant compounds, like vitamins, especially ascorbic acid (vitamin C), were found to have significant effects on the plant development, photosynthesis, cell division, and even raised the plant tolerance to both biotic and abiotic stresses [2,20]. Riboflavin (vitamin B2) is required for the plant cell energy metabolism and represents a good photosensitizer that is incorporated with electron transport during photosynthesis [21,22]. Additionally, it promotes chlorophyll and carotenoids inside the plant cells, which improves the agricultural yields and their quality [2,23]. Vitamins play a promising role in decreasing drought stress in various plants through enhancing their physiological and biochemical responses to water deficit conditions [24]. Foliar spraying of vitamins can enhance the plant antioxidant systems and photosynthesis, reduce plant oxidative damage, stimulating the osmolyte production, and also, water retention mechanisms, activating the enzymes involved in stress response [25,26]. Moreover, their foliar spray under stress, ascorbic acid improves fruit tree productivity, fruit quality, and decreases fruit cracks and losses [27].

Previous studies have examined the impact of water scarcity on pomegranate trees through various watering treatments, but inconsistent results make it challenging to compare field studies due to factors such as crop load, tree age, irrigation frequency, and environmental conditions [28,29]. There are limited studies on how water distribution and anti-stress substances impact on Manfalouty pomegranate trees characteristics. This paper focuses on determining the most effective irrigation rates for Manfalouty pomegranate trees. The goal is to optimize the trees’ growth, yield, bioactive compounds, and fruit quality. The study also examines the impact of foliar spray applications of glycine, ascorbic, and riboflavin acids on the trees’ physiological response.

2. Materials and Methods

2.1. Experimental Site

For two consecutive seasons (2023 and 2024), the field experiment was carried out at the research farm of the Arab El-Awammer Research Station, Agric. Res. Center (ARC), Assiut Governorate, Egypt. The research farm is situated between latitudes (27°17′12.0″ N 31°13′29.3″ E). The trees were subjected to the same pest control and fertilizer practices as the orchard. The methods described by Klute [30] and Jackson [31] were used to define the physical and chemical parameters of the experimental soil, which is sandy calcareous soil (

Table 1. Physicochemical properties from the experimentation site.

Physical Properties
Particle size distribution (%)			Texture Class	Moisture content (Volumetric %)			OM (%)	CaCO3 (%)	Bulk density (g/cm3)
Sand	Silt	clay		S.P.	F.C.	W.P.
90.20	6.10	3.70	Sandy	23.7	10.6	4.7	0.43	32.15	1.61
Chemical Properties
pH (1-1)	EC (dS/ m) (1:1)	Available phosphorus (mg/L)	TN (%)	Soluble cations (mg/L)				Soluble anions (mg/L)
				Ca++	Mg++	Na+	K+	Co3−−+HCo3−	Cl−
8.12	0.6	7.85	0.03	2.48	1.58	0.68	0.85	2.57	1.81

Electrical conductivity (EC), organic matter (OM), total nitrogen (TN), field capacity (F.C.), (S.P.), wilting point (W.P.).

).

Table 2. Mean monthly meteorological data during two seasons 2023 and 2024.

Year	Month	Temperature (T max °C)	Temperature (T min °C)	Relative Humidity (RH %)	Wind Speed (km/h)	Sunshine (h/day)	ETo (mm/day)
2023	March	27.1	12.1	34.3	9.9	9.9	5.74
	April	31.5	15.1	25.5	14.2	10.3	7.49
	May	34.6	19.2	26.4	13.5	11.4	8.35
	June	38.3	24.2	28.6	16.7	12.3	9.90
	July	39.7	24.5	30.9	14.8	12.2	10.02
	August	38.7	24	37.7	15.7	11.9	9.98
	September	37.4	22.7	34.4	14.5	10.8	8.06
	October	31.9	18.7	47.5	13.9	10.0	6.04
	November	28.9	14.8	50	10.4	9.4	5.17
2024	March	26.6	11.1	36.5	10.9	9.9	5.97
	April	32.1	16.6	32.6	13.7	10.3	7.97
	May	36.1	20.5	24.1	14.6	11.4	9.49
	June	40.9	24.8	25.1	13.8	12.3	9.5
	July	40.3	26.1	26.8	11.6	12.2	10.6
	August	39.9	26	28.5	15.1	11.9	9.7
	September	36.7	23.5	38.8	16.7	10.8	8.1
	October	31.4	17.4	44.8	15.9	10.0	6.0
	November	25.3	12.2	56.3	15.4	9.4	4.0

displays the research region’s climate data for the two seasons.

2.2. Treatments and Experimental Design

The investigation was carried out on pomegranate trees (Punica granatum L.) over a two-year period in 2023 and 2024. These trees, which were nine years old at the time of the study, were planted using 3 × 3 m spacing pattern. Two driplines were positioned in each tree row as part of a drip irrigation system. Two drippers, each with a 16 L h⁻¹ flow rate, were installed on each tree. Treatments were applied to thirty-six trees that were selected to have the most consistent growth and vigor possible. Twelve treatment groups, each with three replicates, were created from them. This study employed a split-plot setup with three replications and a randomized complete block design. In the main plot, three irrigation regimes were assigned: 100% crop evapotranspiration (ETc), 80% (ETc), and 60% (ETc). The four antioxidants treatments that make up spraying techniques were control treatment (water), riboflavin, ascorbic acid, and glycine acid spraying with 150 ppm, was assigned to the sub-plot. Three stages of foliar sprays were carried out: in April, during full bloom; in June, following two months of fruit set; and in July, one month later.

2.3. Irrigation Water Applied

Crop evapotranspiration (ETc) = ETo × Kc

where ETo referred to reference evapotranspiration using Penman Monteith equation [32], Kc is the crop coefficient [33]; their values are presented in (Tables S1 and S2).

Irrigation water applied (I.Ra) referred to the amount of actual irrigation water which calculated as follows:

$$\mathrm{I}.Ra={\displaystyle \frac{ETc+LF}{Er}}$$

where I.Ra is the total actual irrigation water applied mm/interval, ETc is the crop evapotranspiration, LF is the leaching factor 10%, and Er represents the irrigation system efficiency.

$$\mathrm{Irrigation}\mathrm{water}\mathrm{productivity}(\mathrm{IWP})={\displaystyle \frac{\mathrm{F}\mathrm{r}\mathrm{u}\mathrm{i}\mathrm{t}yield(\mathrm{k}\mathrm{g}/\mathrm{h}\mathrm{a})}{Irrigationwaterapplied(\mathrm{m}3/\mathrm{h}\mathrm{a})}}$$

2.4. Morphological and Physiological Assay of Tree Leaves

A—Vegetative growth traits

In April, four major branches that were similar in size and dispersed across the tree’s four hands were selected and categorized for the following vegetative measurements.

• Length of shoot (cm).
• Number of leaves/shoot.
• Area of leaf (cm²), was estimated by using the following formula as stated by Ahmed and Morsy [34]: Leaf area = 0.41 (Length of leaf × Width of leaf) + 1.83.
• The total chlorophyll (mg/g F.W.) of the leaves was extracted using methanol, the plant leaf was suspended in 10 mL of 95% methanol overnight in a falcon tube until the leaves loss their green color, discard the leaves tissue, and centrifuge at 6000× g for 5–10 min to eliminate any tissue residue; the supernatant then measured at 650 and 665 nm [9], and was computed using the equations of Lichtenthaler et al. [35].

B—Physiological traits

• The total antioxidants (mg/g fresh weight) were detected by mixing 0.5 mL of leaf extract with 4 mL of ammonium molybdate reagent, incubated for 90 min. in 100C water bath; after cooling, the supernatant was measured at 695 nm following techniques of Prieto et al. [36] and Ibrahim et al. [37].
• Total flavonoids (mg/g fresh weight) were measured in the leaves according to methods of Chang et al. [38] and Mahmoud et al. [9]. One mL of leaf extract was mixed with and one mL of aluminum chloride reagent and 0.5 mL potassium acetate buffer, incubated in room temperature for 15–20 min; then, the absorbance was measured at 496 nm using spectrophotometer; obtained data were calculated using standard curve of quercetin.
• Total phenols (mg/g fresh weight) were measured at 750 nm using Folin-Ciocalteu reagent [9,39]. The leaf extract was mixed with Folin-Ciocalteu diluted with 1:10 with distilled water and disodium carbonate (7.5%) and incubated in room for 30 min; then, the absorbance was measured at 750 nm using spectrophotometer and the data were calculated using gallic acid standard curve.

2.5. Yield Parameters

At harvest time (middle of September), the total fruit yield per tree was recorded. Then, total Yield Ton/fed. (one feddan = 4200 m²) was estimated according to the following equation:

Yield (Ton/fed.) = yield per tree × No. of trees per fed./1000

2.6. Fruit Quality

A random sample of ten fruits from each treatment was picked to determine the physical and chemical measures including fruit length (cm), fruit diameter (cm), fruit weight (g), and arils weight (%), and fruit creaking (%). Fruit total soluble solids (TSS), and total sugar and acidity (TA %) were measured following A.O.A.C. [40]. Anthocyanin content (mg/100g FW) was measured at 535 nm following Ranganna [41] method. Total antioxidants (mg/g fresh weight), total phenols (mg/g fresh weight), and total flavonoids (mg/g fresh weight) were also measured following the previous mentioned methods. Ascorbic acid (V.C.) content (mg of ascorbic acid/100 g F.W.) was determined in fruit juice by titration with, 2,6-Dichlorophenol indophenol blue dye according to A.O.A.C. [40].

2.7. Statistical Analysis

Data were statistically analyzed by Statistix version 8.1. To compare means, we utilized the least significant difference test (p ≤ 0.05). Pearson Correlation represented a statistical method to calculate the similarity or the correlation between two sites through comparing their characteristics and attributes throughout the data and calculating a relation score ranging from −1 to +1 [42]. High score indicates high similarity, and low scores revealed low correlations, while zero score or near results indicates no correlation. Principal component analysis (PCA) was performed to clear the interactions between variables within different times using PAST software v.2.11 [43].

3. Results

3.1. Irrigation Applied Water (L/Tree)

The pomegranate tree’s monthly irrigation water application is shown in Figure 1. According to the results, the volume of irrigation water applied was significantly impacted by the irrigation regimes, which were set at 100%, 80%, and 60% ETc. The irrigation applied water for 60%, 80%, and 100% ETc in the first year (2023) was 5159.8, 6879.7, and 8599.7 m³/Fed./season, respectively. Water applied for irrigation under the same regimes was 5196.4, 6928.5, and 8660.6 m³/Fed./season in the second year (2024). The data presented in Tables S1 and S2 show the effect of the irrigation regime on the irrigation depth (mm) and average of irrigation time (hour). The data shows the minimum and maximum irrigation water depth values. It is clear from the data that the highest irrigation depth was during July during both growing seasons. The lowest values were in November and March, at different irrigation levels. The table also shows that the number of irrigation hours varied during the growing months, with the maximum number of irrigation hours occurring during July at 100% ETc.

3.2. Impact of Antioxidant Spraying on Pomegranate Trees’ Vegetative Growth Under Three Irrigation Regimes

Data in

Table 3. Effect of irrigation regime and antioxidant spraying (glycine, ascorbic acid, and riboflavin) on shoot length (cm), number leaves/shoot, and leaf area (cm²) of Manfalouty pomegranate trees during the 2023 and 2024 seasons.

Season 2023
Irrigation (ETc)	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc
Spraying	Shoot length (cm)			Number leaves/shoot			Leaf area (cm2)
Control	51.77 ± 0.23 i	55.42 ± 0.42 g	59.99 ± 0.01 cd	61.20 ± 0.20 k	67.74 ± 0.04 i	71.77 ± 0.38 d	5.22 ± 0.02 e	5.62 ± 0.03 d	6.15 ± 0.25 c
Glycine	57.58 ± 0.50 f	60.55 ± 1.00 c	63.67 ± 0.10 a	70.21 ± 0.21 f	71.87 ± 0.10 d	77.70 ± 0.20 a	5.63 ± 0.03 d	6.15 ± 0.10 c	6.91 ± 0.01 a
Ascorbic acid	52.88 ± 0.10 h	56.98 ± 0.02 f	59.21 ± 0.21 e	63.53 ± 0.23 j	69.53 ± 0.03 g	73.19 ± 0.19 c	5.36 ± 0.20 e	5.97 ± 0.00 c	6.72 ± 0.12 b
Riboflavin	55.48 ± 0.48 g	59.58 ± 0.30 de	62.56 ± 0.50 b	68.48 ± 0.40 h	70.90 ± 0.10 e	76.67 ± 0.22 b	5.55 ± 0.05 d	5.99 ± 0.00 c	6.68 ± 0.20 b
Season 2024
Control	45.65 ± 0.05 i	53.44 ± 0.44 g	59.33 ± 0.57 c d	53.23 ± 0.23 j	65.32 ± 0.32 h	71.69 ± 0.33 d	4.46 ± 0.10 g	5.11 ± 0.21 e	5.67 ± 0.10 c
Glycine	55.56 ± 0.40 f	58.54 ± 0.46 d	64.70 ± 0.30 a	68.54 ± 0.46 f	70.54 ± 0.54 e	79.13 ± 0.13 a	4.75 ± 0.15 f	5.51 ± 0.09 c d	6.17 ± 0.00 a
Ascorbic acid	50.88 ± 0.12 h	54.98 ± 1.00 f	60.21 ± 0.21 c	61.03 ± 0.03 i	66.77 ± 0.22 g	73.97 ± 0.03 c	4.56 ± 0.11 f g	5.35 ± 0.10 d	6.11 ± 0.01 ab
Riboflavin	53.45 ± 0.45 g	56.87 ± 1.64 e	62.27 ± 0.83 b	66.88 ± 0.12 g	70.12 ± 0.12 e	78.60 ± 0.10 b	4.61 ± 0.06 f g	5.43 ± 0.17 d	5.92 ± 0.02 b

Values are given as the mean ± error deviation (n = 3). Different letters indicate statistical differences according to Duncan’s multiple range tests at p < 0.05.

demonstrated how pomegranate morphological characteristics, such as shoot length (cm), number of leaves per shoot, and leaf area (cm²), were affected by the application of several antioxidants (glycine, ascorbic acid, and riboflavin) under three irrigation regimes (60%, 80%, and 100% ETc). Vegetative growth varied greatly, according to the data; all vegetative attributes showed a considerable decline with decreasing irrigation levels up to 60% ETc, while 100% ETc irrigation produced the highest growth values. The findings also demonstrated that all antioxidant treatments considerably improved the growth characteristics when compared to the control treatment; however, glycine was found to be the most effective treatment, followed by ascorbic acid and riboflavin. Regarding the relationship between irrigation levels and spray treatments, the glycine treatment under 100% ETc produced the highest results, yielding shoot lengths of 63.67 cm² (1st season, control 59.99 cm²) and 64.70 cm² (2nd season, control 59.33 cm²), leaf area of 6.91 cm² (1st season, control 6.15 cm²) and 6.17 cm² (2nd season, control 5.67 cm²), and leaf number of 77.70 (1st season, control 71.77 and 79.13 (2nd season, control 71.67). For 60% ETc, glycine treatment gives the best results yielding shoot lengths of 57.58 cm (1st season, control 51.77 cm) and 55.56 cm (2nd season, control 45.65 cm), leaf area of 5.63 cm² (1st season, control 5.22 cm²) and 4.75 cm² (2nd season, control 4.46), and leaf number of 70.21 (1st season, control 61.2) and 68.54 (2nd season, control 53.2). It is important to note that the investigated vegetative growth characteristics did not significantly differ between the 100% irrigation level treatment and the 80% irrigation level treatment with glycine spray. This finding could help us to preserve 20% of the applied water and get high pomegranate morphological characteristics, such as shoot length (cm), number of leaves per shoot, and leaf area (cm²).

3.3. Impact of Antioxidant Spraying on Pomegranate Leaves’ Total Chlorophyll, Total Antioxidants, Total Phenols, and Total Flavonoids Under Three Irrigation Regimes

The data in Figure 2 demonstrated how the total chlorophyll of pomegranate leaves under three irrigation regimes (60, 80%, and 100% ETc.) was affected by the application of several antioxidants (glycine, ascorbic acid, and riboflavin). Without treatments, the chlorophyll content of the leaves decreased from 52.2 (100% ETc) to 46.29 and 38.33 mg/g F.W. in the 1st season, and from 52.7 (ETc 100%) to 46.06 and 38.21 mg/g F.W. in the second season when the watering schedule was reduced from 100% to 80% and 60%. Pomegranate leaves with various antioxidant spray treatments have higher levels of chlorophyll overall. Glycine treatment raised the leaves’ total chlorophyll content to 47.43 (60% ETc), 52.57 (80% ETc), and 58.99 (100% ETc) mg/g F.W. in the first season and 47.12 (60% ETc), 52.14 (80% ETc), and 59.5 (100% ETc) mg/g F.W. in the second. Riboflavin was yielding from 45.35 to 58.09 mg/g F.W. in the first season and 45.23 to 59 mg/g F.W. total chlorophyll in the second for 60% ETc and 100% ETc, respectively. Furthermore, when there was insufficient water, the chlorophyll content of the leaves improved with all spray treatments. Among the key findings was that there were no appreciable variations between 100% irrigation and 80% irrigation with riboflavin or glycine spraying.

Total antioxidants, total phenols, and total flavonoids in leaves were all significantly impacted by the different irrigation water regimes, and they were progressively reduced by reducing the irrigation from 100% to 80% and 60% in both seasons, according to data in

Table 4. Effect of irrigation regime and antioxidant spraying (glycine, ascorbic acid, and riboflavin) on total antioxidants (mg/g fresh weight), total phenols (mg/g fresh weight), and total flavonoids (mg/g fresh weight) in the leaves of Manfalouty pomegranate trees during the 2023 and 2024 seasons.

Season 2023
Irrigation (ETc)	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc
Spraying	Total antioxidants			Total phenols			Total flavonoids
Control	104.61 ± 0.50 d	88.51 ± 0.10 g	77.32 ± 0.28 j	89.78 ± 0.16 e	71.17 ± 0.82 h	67.79 ± 1.32 j	44.13 ± 0.23 d e	43.52 ± 0.46 e	35.76 ± 0.91 i
Glycine	112.67 ± 0.60 a	105.14 ± 0.93 d	88.32 ± 0.28 g	96.72 ± 0.14 a	92.91 ± 0.02 d	79.28 ± 0.63 g	49.10 ± 0.55 a	44.34 ± 0.16 d	41.86 ± 0.17 f
Ascorbic acid	110.16 ± 0.27 c	92.24 ± 0.05 f	84.46 ± 0.44 i	94.13 ± 0.03 c	85.07 ± 0.98 f	68.13 ± 0.81 j	46.46 ± 0.41 c	44.19 ± 0.27 d	37.94 ± 0.05 h
Riboflavin	111.21 ± 0.37 b	96.69 ± 0.53 e	87.38 ± 0.33 h	95.10 ± 0.10 b	92.32 ± 1.06 d	69.61 ± 0.85 i	47.24 ± 0.21 b	44.36 ± 0.05 d	38.78 ± 0.14 g
Season 2024
Control	103.89 ± 0.78 d	87.68 ± 0.78 g h	76.82 ± 0.75 j	89.81 ± 0.10 f	70.23 ± 0.12 i	66.33 ± 0.11 l	44.40 ± 0.10 d	42.86 ± 0.31 e	34.87 ± 0.52 i
Glycine	113.29 ± 0.62 a	103.93 ± 0.81 d	87.82 ± 0.75 g	96.91 ± 0.05 a	92.71 ± 0.22 d	78.11 ± 0.67 h	49.56 ± 0.23 a	44.17 ± 0.29 d	41.33 ± 0.34 f
Ascorbic acid	110.49 ± 0.50 c	92.11 ± 0.12 f	83.96 ± 0.93 i	94.22 ± 0.07 c	83.75 ± 0.48 g	67.37 ± 0.06 k	46.59 ± 0.53 c	44.13 ± 0.15 d	37.57 ± 0.50 h
Riboflavin	111.71 ± 0.08 b	95.92 ± 0.56 e	86.88 ± 0.82 h	95.18 ± 0.08 b	90.82 ± 0.75 e	68.51 ± 0.46 j	47.31 ± 0.27 b	44.23 ± 0.20 d	38.41 ± 0.36 g

Values are given as the mean ± standard error (n = 3). Different letters indicate statistical differences according to Duncan’s multiple range tests at p < 0.05.

. Compared to untreated trees, leaves treated with glycine, ascorbic acid, and riboflavin spraying had higher levels of total antioxidants, total phenols, and total flavonoids, which is indicative of their functions in increasing plant stress. The best spray treatment for raising the amount of total antioxidants in the leaves was glycine, which produced 102.05 (1st season) and 101.68 mg/g fresh weight (2nd season), 89.64 (1st season) and 89.24 mg/g fresh weight (2nd season) of total phenols, and 45.10 (1st season) and 45.02 mg/g fresh weight (2nd season) of total flavonoids. Following glycine, riboflavin spraying improved the levels of total antioxidants (98.43 mg/g fresh weight in the 1st season and 98.17 mg/g fresh weight in the 2nd), total phenols (85.68 mg/g fresh weight in the 1st season and 84.84 mg/g fresh weight in the 2nd season), and total flavonoids (43.46 mg/g fresh weight in the first season and 43.31 mg/g fresh weight in the second season). In terms of increasing the leaf content of total antioxidants (95.62 mg/g fresh weight in the 1st season and 95.52 mg/g fresh weight in the 2nd), total phenols (82.44 mg/g fresh weight in the 1st season and 81.78 mg/g fresh weight in the 2nd season), and total flavonoids (42.87 mg/g fresh weight in the 1st season and 42.77 mg/g fresh weight in the 2nd season), ascorbic acid treatment was the third best spray treatment.

3.4. Impact of Antioxidant Spraying on Pomegranate Yield Parameters and Fruit Creaking Under Three Irrigation Regimes

The data presented in

Table 5. Effect of irrigation regime and antioxidant spraying (glycine, ascorbic acid, and riboflavin) on yield (Ton/fed) and fruit creaking (%) of Manfalouty pomegranate trees during the 2023 and 2024 seasons.

Season 2023
Irrigation (ETc)	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc
Spraying	Yield (Ton/fed.)			Fruit Creaking (%)
Control	10.71 ± 0.07 h	13.54 ± 0.36 e	14.21 ± 0.27 cd	6.98 ± 0.02 f	8.03 ± 0.03 d	10.34 ± 0.04 a
Glycine	12.23 ± 0.63 f	14.46 ± 0.21 bc	15.18 ± 0.15 a	6.02 ± 0.02 i	7.55 ± 0.15 e	9.87 ± 0.07 c
Ascorbic acid	11.36 ± 0.11 g	13.80 ± 0.27 de	14.51 ± 0.14 bc	6.22 ± 0.02 h	7.55 ± 0.15 e	10.07 ± 0.07 b
Riboflavin	11.97 ± 0.10 f	14.16 ± 0.06 cd	14.78 ± 0.17 ab	6.65 ± 0.05 g	7.52 ± 0.03 e	9.99 ± 0.01 b
Season 2024
Control	10.07 ± 0.07 i	13.64 ± 0.02 e	14.48 ± 0.10 cd	6.95 ± 0.05 f	8.00 ± 0.50 d	11.08 ± 0.37 a
Glycine	12.08 ± 0.21 f	14.46 ± 0.08 cd	15.43 ± 0.06 a	6.02 ± 0.02 h	7.34 ± 0.04 ef	9.91 ± 0.32 c
Ascorbic acid	11.25 ± 0.13 h	13.77 ± 0.10 e	14.72 ± 0.21 bc	6.32 ± 0.02 gh	7.41 ± 0.01 e	10.39 ± 0.06 b
Riboflavin	11.64 ± 0.22 g	14.21 ± 0.19 d	14.79 ± 0.21 b	6.54 ± 0.04 g	7.48 ± 0.08 e	10.52 ± 0.10 b

Values are given as the mean ± standard error (n = 3). Different letters indicate statistical differences according to Duncan’s multiple range tests at p < 0.05.

exhibited a similar pattern across the two study seasons. This indicates how the irrigation water regime, glycine, ascorbic acid, and riboflavin spraying, and their interactions affected fruit creaking (%) and yield, which is expressed as yield tons/fed. Reducing irrigation from 100% to 80% and 60% in both seasons, respectively, resulted in a progressive decrease in yield (ton/fed.); in the 2023 season, the yield (tons/fed.) was 14.67 (100% ETc), 13.99 (80% ETc), and 11.57 (60% ETc), while in the 2024 season, it was 14.86 (100% ETc), 14.02 (80% ETc), and 11.26 (60% ETc). The output of Manfalouty pomegranate trees was greatly boosted by foliar spraying with glycine, ascorbic acid, and riboflavin. The maximum yield values were 13.95 ton/fed. (1st season) and 13.99 tons/fed (2nd season) when glycine treatment was used. Following glycine, riboflavin produced yields of 13.64 ton/fed (1st season) and 13.55 ton/fed (2nd season). Ascorbic acid came in second with yields of 13.22 ton/fed (1st season) and 13.25 ton/fed (2nd season). Untreated (control) trees, on the other hand, produced the lowest results by 12.82 ton/fed in the first and 12.73 tons/fed in the second. In both seasonal tests, there was no discernible difference between irrigation at 100% and irrigation at 80% with glycine, riboflavin, or ascorbic acid spraying. The results also demonstrated that all spray treatments reduced the cracking rate, with the glycine spray treatment being the most effective in this respect. Reducing irrigation from 100% to 80% and 60% in both seasons, respectively, resulted in a progressive decrease in fruit creaking (%). The findings also demonstrated that when the irrigation rate was reduced from 100% to 60%, the cracking rate likewise fell, going from 10.07%, 7.66%, to 6.47% in the first season and from 10.48%, 7.56%, to 6.46% in the second.

3.5. Impact of Antioxidant Spraying on Pomegranate Fruit Quality Under Three Irrigation Regimes

Results in

Table 6. Effect of irrigation regime and antioxidant spraying (glycine, ascorbic acid, and riboflavin) on fruit length (cm), fruit diameter (cm), fruit weight (g), and arils weight (%) of Manfalouty pomegranate trees during the 2023 and 2024 seasons.

Season 2023
Irrigation (ETc)	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc
Spraying	Fruit Length (cm2)			Fruit Diameter (cm2)			Fruit Weight (g)			Arils Weight (%)
Control	7.76 ± 0.05 g	8.28 ± 0.03 d	8.54 ± 0.04 c	8.78 ± 0.06 g	9.08 ± 0.09 ef	9.46 ± 0.06 cd	336.69 ± 1.00 k	395.98 ± 4.35 g	420.00 ± 2.00 d	50.11 ± 0.11 i	53.97 ± 1.00 ef	55.02 ± 0.33 bc d
Glycine	8.15 ± 0.05 de	8.54 ± 0.01 c	8.77 ± 0.07 a	9.15 ± 0.15 e	9.63 ± 0.06 b	9.79 ± 0.01 a	368.00 ± 1.00 h	419.04 ± 1.00 d	455.00 ± 1.00 a	53.74 ± 0.52 fg	55.00 ± 0.30 cd	56.46 ± 0.46 a
Ascorbic acid	8.01 ± 0.01 f	8.48 ± 0.02 c	8.58 ± 0.18 bc	8.96 ± 0.02 f	9.39 ± 0.02 d	9.52 ± 0.02 bc	345.00 ± 1.00 j	402.75 ± 1.75 f	428.31 ± 0.30 c	52.99 ± 0.00 gh	54.53 ± 1.03 de f	55.99 ± 0.00 ab
Riboflavin	8.04 ± 0.04 ef	8.51 ± 0.02 c	8.68 ± 0.08 ab	9.15 ± 0.05 e	9.45 ± 0.00 cd	9.60 ± 0.10 b	361.69 ± 1.00 i	409.50 ± 1.50 e	438.00 ± 2.00 b	52.19 ± 0.19 h	54.89 ± 1.00 cd e	55.58 ± 0.40 ab c
Season 2024
Control	7.59 ± 0.05 h	8.19 ± 0.07 e	8.56 ± 0.02 c	8.91 ± 0.08 h	9.22 ± 0.04 e	9.47 ± 0.04 cd	333.31 ± 0.30 j	387.83 ± 3.53 g	420.40 ± 1.44 d	50.02 ± 0.02 g	53.43 ± 0.43 de	56.56 ± 0.42 b
Glycine	8.06 ± 0.06 f	8.55 ± 0.05 c	8.88 ± 0.02 a	9.11 ± 0.04 f	9.53 ± 0.06 bc	9.80 ± 0.10 a	351.69 ± 1.00 h	418.67 ± 1.61 d	463.27 ± 2.61 a	53.88 ± 1.00 cd	54.98 ± 1.00 c	58.06 ± 0.94 a
Ascorbic acid	7.87 ± 0.02 g	8.34 ± 0.02 d	8.61 ± 0.01 c	8.88 ± 0.02 h	9.40 ± 0.01 d	9.61 ± 0.01 b	338.31 ± 1.30 i	392.09 ± 0.31 f	430.17 ± 1.76 c	52.55 ± 0.40 ef	54.20 ± 0.20 cd	57.55 ± 0.89 ab
Riboflavin	8.03 ± 0.03 f	8.42 ± 0.02 d	8.76 ± 0.10 b	9.01 ± 0.01 g	9.43 ± 0.01 d	9.61 ± 0.01 b	350.07 ± 1.10 h	396.75 ± 3.75 e	455.27 ± 2.61 b	52.02 ± 0.98 f	54.28 ± 0.28 cd	57.37 ± 0.63 ab

Values are given as the mean ± standard error (n = 3). Different letters indicate statistical differences according to Duncan’s multiple range tests at p < 0.05.

reveal that dimensions (height and diameters), fruit weight (g), and arils weight % of Manfalouty pomegranate decreased significantly with the irrigation regime being reduced from 100% to 80% and 60% in both seasons. On the other hand, spraying pomegranate trees with glycine or ascorbic acid or riboflavin had a significant effect on improving fruit length, diameter, weight (g), and aril weight %. All Spraying treatments improved the length of fruit, diameter, and weight of the percentage of aril resulting from irrigation deficiency from 100% to 80% to 60% ETc. The best treatment was to spray trees with glycine. There was also no significant difference between the ascorbic acid treatment and the riboflavin treatment in the aryl weight. Data in

Table 7. Effect of irrigation regime and antioxidant spraying (glycine, ascorbic acid, and riboflavin) on total soluble solids (TSS), total sugar and acidity (TA) (%) of Manfalouty pomegranate trees during the 2023 and 2024 seasons.

Season 2023
Irrigation (ETc)	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc	60% ETc	80% ETc	100% ETc
Spraying	TSS (%)			Total Sugar (%)			TA (%)
Control	16.22 ± 0.22 c	15.36 ± 0.06 e	14.32 ± 0.02 h	13.00 ± 0.20 b	12.40 ± 0.10 e	12.12 ± 0.12 f	1.13 ± 0.05	1.10 ± 0.08	1.08 ± 0.11
Glycine	16.93 ± 0.05 a	15.78 ± 0.08 d	14.83 ± 0.07 f	13.44 ± 0.04 a	12.87 ± 0.03 bc	12.23 ± 0.03 ef	1.08 ± 0.07	1.05 ± 0.04	1.02 ± 0.02
Ascorbic acid	16.66 ± 0.06 b	15.34 ± 0.04 e	14.54 ± 0.12 gh	13.02 ± 0.02 b	12.55 ± 0.05 d	12.19 ± 0.09 f	1.10 ± 0.07	1.09 ± 0.09	1.06 ± 0.00
Riboflavin	16.79 ± 0.03 ab	15.50 ± 0.5 e	14.76 ± 0.06 fg	12.98 ± 0.02 b	12.76 ± 0.10 c	12.21 ± 0.01 f	1.13 ± 0.11	1.09 ± 0.00	1.07 ± 0.03
Season 2024
Control	16.67 ± 0.03 c	15.56 ± 0.04 f	14.78 ± 0.02 j	14.00 ± 0.30 c	13.43 ± 0.03 e	12.34 ± 0.04 g	1.13 ± 0.09	1.10 ± 0.05	1.09 ± 0.08
Glycine	16.99 ± 0.08 a	15.78 ± 0.02 d	15.34 ± 0.06 g	14.36 ± 0.06 a	13.69 ± 0.09 d	12.65 ± 0.05 f	1.08 ± 0.08	1.03 ± 0.02	1.02 ± 0.03
Ascorbic acid	16.82 ± 0.03 b	15.66 ± 0.04 e	14.98 ± 0.02 i	14.03 ± 0.03 bc	13.56 ± 0.04 de	12.54 ± 0.04 f	1.10 ± 0.07	1.07 ± 0.01	1.06 ± 0.05
Riboflavin	16.88 ± 0.02 b	15.69 ± 0.01 e	15.07 ± 0.11 h	14.21 ± 0.01 ab	13.65 ± 0.05 d	12.61 ± 0.01 f	1.11 ± 0.10	1.08 ± 0.07	1.07 ± 0.11

Values are given as the mean ± standard error (n = 3). Different letters indicate statistical differences according to Duncan’s multiple range tests at p < 0.05.

cleared the effect of irrigation regime or and spraying with glycine, ascorbic acid, or riboflavin on total soluble solids (TSS %), total sugars, and acidity (TA %). Decreasing the irrigation regime from 100% to 80% and 60% caused an increase in TSS%, total sugars, and acidity, while this increase in acidity was not significant between the different irrigation treatments. The results also show that spraying Manfalouty pomegranate trees with glycine, ascorbic acid, or riboflavin had a significant effect on promoting TSS%, total sugars, in comparison to the control treatment. The highest values of TSS were recorded with fruits under the 60% irrigation level with glycine spraying by 16.93% (1st season) and 16.99% (2nd season), while the lowest values of TSS% were recorded at the 100% irrigation level without spraying 14.32% (1st season) and 14.78% (2nd season). The highest values of total sugars were recorded in the fruits of trees irrigated at 60% with glycine spraying giving 13.44 (1st season) and 14.36% (2nd season), while the lowest values were recorded in trees irrigated at 100% without spraying giving 12.12 (1st season) and 12.34% (2nd season), as well no significant difference or a slight significant difference between them and the other spraying treatments under the same irrigation level of 100%. On the other hand, there was no significant effect between the different spray treatments on the acidity. However, there was no significant effect between the interaction between irrigation treatments 100%, 80%, and 60%, and different spray treatments, glycine, ascorbic acid, or riboflavin, in both study seasons on acidity.

Data presented in Figure 3A,B indicated that vitamin C (VC) contents (Figure 3A) and anthocyanin content (Figure 3B) were significantly affected by different irrigation treatments in both seasons. However, the highest level and significance of VC contents were 23.66 (1st season) and 23.65 mg/100 g F.W. (2nd season), and average levels of anthocyanins were 54.87 (1st season) and 55.58 mg/100 g FW (2nd season), which was noticed under irrigation regime 60%. The lowest level of V.C contents were 20.52 (1st season) and 21.24 mg/100 g F.W. (2nd season), and lowest levels of anthocyanins were 50.85 (1st season) and 51.36 mg/100 g F.W. (2nd season) that were recorded under full irrigation at 100%. On the other hand, moderate irrigation level at 80% exhibited an intermediate value of VC contents by 22.19 (1st season) and 22.41 mg/100 g F.W. (2nd season), and for anthocyanins, were 54.06 (1st season) and 53.70 mg/100 g F.W. (2nd season). Unsprayed fruits had lower vitamin C by 21.46 (1st season) and 21.85 mg/100 g F.W. (2nd season), and for anthocyanins, were 52.56 (1st season) and 53.01 mg/100 g F.W. (2nd season). The best fruits in terms of vitamin C by 22.72 (1st season) and 22.98 mg/100 g F.W. (2nd season), anthocyanins were those sprayed with ascorbic acid by 53.70 (1st season) and 54.19 mg/100 g F.W. (2nd season). When studying the interaction between different irrigation levels and spray treatments, it was found that the fruits with the highest content of vitamin C were 24.27 (1st season) and 24.31 mg/100 g F.W. (2nd season), and anthocyanins were 55.67 (1st season) and 55.98 (2nd season) were those that were sprayed with ascorbic acid below the irrigation at 60%.

The results in Figure 4A–C clearly showed that total antioxidants, total phenols, and total flavonoids in fruits were significantly affected by different irrigation water regime, and they were gradually decreased by decreasing the irrigation from 100% ETc to 60% ETc in both seasons. In addition to that, foliar spraying with antioxidant treatments increased the total antioxidants, phenols, and flavonoid contents in fruits compared to untreated trees, giving highest values in trees irrigated with 100% sprayed with glycine. The content of pomegranate juice Manfalouty of total antioxidants were 30.33 (1st season) and 30.86 mg/g fresh weight (2nd season), total phenols were 19.57 mg/g fresh weight in the first season. While, in the second season, the juice of the fruits of irrigation regime 100% trees that were sprayed with riboflavin gave the highest values of total phenols (21.08 mg/g fresh weight), there was no significant difference between it and the trees sprayed with glycine under the same irrigation regime (21.02 mg/g fresh weight). On the other hand, the data also showed that spraying irrigated pomegranate trees with irrigation 100% spraying with riboflavin gave the highest values of total flavonoids (10.25 mg/g fresh weight). There was no significant difference between it and the trees sprayed with glycine under the same irrigation regime (10.08 mg/g fresh weight) in the first season, while in the second season, it yielded 9.47 mg/g fresh weight.

3.6. Irrigation Water Productivity (IWP kg/m³)

The data presented in Figure 5 provides an illustration of how antioxidant spraying treatments and levels of irrigation impact the irrigation water productivity (IWP). The primary objective of IWP in agricultural production is to either increase food production using the same amount of water resources or maintain the same level of food production while reducing water usage. When pomegranate orchards were irrigated at 100% ETc compared to 80% and 60% ETc, there was a significant decrease in IWP. Remarkably, the study discovered that the highest IWP was obtained with irrigation and glycine spraying at less than 60% ETc, with values of 2.37 and 2.32 kg/m³.

3.7. Statistical Correlations

-Pearson correlation

Red and blue colors indicate negative and positive correlations, respectively; the deeper color represents more significant of the corresponding correlation. The correlations between fruit length (FL), fruit dimeter (FD), fruit weight (FW), arils weight % (FG), total soluble solids % (TSS), sugars % (FS), acidity % (FA), anthocyanins (FAN), vitamin C (FV.C), total antioxidants (FTA), total phenols (FTP), and total flavonoids (FTF) are shown in Figure 6. By analyzing the correlations throughout the treatments, positive correlations were found between fruit length (FL) and FD 0.91, TSS 0.96, FTP 0.94, FTF 0.91, FTA 0.92, while fruit diameter showed strong positive correlations with TSS 0.98, FA 0.98, FG 0.96. Fruit weight showed positive correlations with FTP 0.98, FTA 0.96, FTF 0.93, TSS 0.92, FS 0.9, and a negative correlation with FA. Total soluble solids (TSS) showed positive correlations with FS0.9, FTA0.91, FTF0.94, and negative correlations with acidity.

-Classical cluster analysis

Cluster analysis data categorized the interaction between morphological, physiological straights, and fruit quality in the form of fruit length (FL), fruit dimeter (FD), fruit weight (FW), arils weight % (FG), TSS % (TSS), sugars % (FS), acidity % (FA), anthocyanins (FAN), vitamin C (FV.C), total antioxidants (FTA), total phenols (FTP), and total flavonoids (FTF), as shown in Figure 7. The cluster analysis clear strong relations between arils weight % and anthocyanins, TSS % and sugars %, vitamin C and total phenols, fruit length and total flavonoids, which is also in agreement with Pearson correlation analysis, while fruit weight and acidity were found as separated outgroups (Figure 7).

4. Discussion

Egyptian farmers were forced to conduct deficit irrigation projects because to the high demand for water and the limited availability; moreover, studies of climate change forecasts suggest that water deficits may worsen in the next years [44]; this makes us preserve all possible amounts of water through rational consumption, trying to reduce the rate of irrigation in agriculture, and searching for safe additives to improve plant growth under conditions of water scarcity. Our findings show that trees that received 80% and 100% ETc irrigation showed increases in shoot length, leaf area, number of leaves/shoots, and chlorophyll content with no significant differences between the two irrigation levels. However, the volume of irrigation water applied was significantly impacted by the irrigation regimes. Previous studies showed that irrigation with the ETc technique ensures plant hydration and unimpeded growth-promoting metabolic activities [45,46]. Trees treated with deficit irrigation ETc exhibit marginally lower vegetative growth and yield than trees treated with 100% ETc; according to Jin et al. [47], water stress can limit plant carbon dioxide uptake, transpiration process, cellular antioxidant activities, and even effects on the cell structure. So, it is important to maintain growth while conserving the irrigation water; these adaptations include enhanced plant growth using plant stimulators, water uptake efficiency, and decreased plant evapotranspiration [48]. The seasonal amount of irrigation water was significantly influenced by the designed irrigation treatments; increase in irrigation-applied water, especially under 100% ETc, could be attributed to direct evaporation increasing. Gaber et al. [49] found that the amounts of irrigation water applied during various months depends on the evapotranspiration rate, so the highest water application occurred in July, reflecting high reference evapotranspiration. In Egypt, during two seasons, it was found that increasing irrigation application to ‘Manfalouty’ pomegranate trees (20-year-old) from 280 to 600 mm causing 24–34% more flowers production, 10% higher fruit production, and about 8.6% lower fruit loss [50]. As a result, throughout the two pomegranate tree growth seasons, the amounts of water applied for seasonal irrigation increased, which is in line with Zaghloul and Moursi [51], Jamshidi et al. [52], and Mansour et al. [53].

Under different water deficit levels, Manfalouty pomegranate trees’ vegetative growth was greatly accelerated by antioxidant additives of glycine, riboflavin, and ascorbic acids, while glycine was recorded as the most efficient growth stimulator at the three irrigation levels. By prioritizing survival above growth and rerouting resources to physiological processes, severe deficit irrigation (60%ETc) significantly reduces a tree’s capacity for photosynthetic development [54,55]; however, glycine foliar spraying enhances plant growth and yield significantly compared to the untreated samples. These results were consistent with Tarantino et al. [56] and Gómez-Bellot et al. [57] who works on pomegranate trees and found that high water stress restricts the plant production of carbohydrates, sugars, pigments, and even their distribution across all vegetative organs of the trees. Previous studies showed that glycine increases photosynthetic rate [58], leaves chlorophyll contents, and leaves stomatal conductance [59], which was in agreement with our findings; foliar applications of glycine showed a positive impact on vegetative growth under a variety of water stressors. According to Leal et al. [54], using suitable plant enhancers, fertilizer application, and irrigation types enhanced the reproductive organs and plant nutrient uptake. Antioxidant-treated trees could reduce water intake, increase yields, and interfere with flower growth and pollination success [57]. Glycine also has protected properties of plant organs growing and expanding from stress and encourages tree growth, which was observed in “Le-Conte” Pear Trees [19], Young Pear Trees [60], and on Navel Orange Trees [61].

In low irrigation, sugars may accumulate and increase the process of starch–sugar conversion, which are crucial for the fruit’s customer choice and market acceptability [62,63]. This result was also consistent with Nasrabadi et al. [64], who observed increasing sugars with low irrigation rates. Fruit total acidity across the treatments indicates that pomegranate acidity levels are less susceptible to changes in irrigation, which could possibly preserve the pomegranate flavor balance in water stress [56]. Water deficit increased the accumulation of plant bioactive agents, flavonoids, vitamins, phenolics, pigments, and antioxidants [10]. These results were also in parallel with in (‘Mollar de Elche’) pomegranate trees [57], in “Le-Conte” pear [19], which recorded increases in antioxidants of leaves and fruits under water stress. Accumulated polyphenols and flavonoids inside the tissues have been documented as essential protective agents of the plant that contribute to plant defense mechanisms in response to both biotic and abiotic stresses [65,66]. On the other hand, sever water stresses decreases the production and levels of active substances in plants by impacting the metabolic pathways of cell secondary metabolites [67]. This is, however, countered by Adiba et al. [44], who observed a decrease in phenolics and antioxidants in both cultivars (cv. Sefri and cv. Wonderful) when subjected to continuous deficit irrigation treatments. Additionally, Król et al. [68] and Farooq et al. [69] describe how drought stress led to a reduction in phenolics in the leaves and roots of grapevine seedlings; this difference in results can be explained by the influence of water stress levels and also the plant genotype, growth stage, tree age, and soil type.

According to the results, spraying with glycine decreased the negative impact of drought on trees by increasing the pomegranate leaves’ photosynthetic pigments, antioxidants, and tree yield. This agrees with Osman [70], who reported that adding glycine and proline to the plant enhanced the antioxidant–yield relationship of pea plants under various drought stages [71] in two maize varieties grown under drought stress [72] in maize plants. Remarkably, the study discovered that the highest IWP was obtained with irrigation and glycine spraying at less than 60% ETc, with values of 2.37 and 2.24 kg/m3. These results are consistent with studies by Zaghloul and Moursi [51] and Gaber et al. [49], who found that irrigation water use efficiency decreased as irrigation water levels rose. These results are also supported by [73,74].

5. Conclusions

An applied amount 6904.1 m3 (80% ETc) of irrigation water per fed. of pomegranate trees in newly reclaimed soils during the growing season using a drip irrigation system in dry areas with spraying treatment with glycine resulted in a good yield compared to not spraying and adding an amount of water equivalent to 100% ETc. The highest vegetative decline was significant, observed with an irrigation level 60% ETc. Glycine treatment enhanced yielding shoot lengths, leaf area, and leaf number. Among the key findings was that there were no appreciable variations between 100% irrigation and 80% irrigation with riboflavin or glycine spraying for leaves’ total chlorophyll. The findings provide valuable insights for sustainable pomegranate cultivation practices that maximize productivity and quality while maintaining plant health using low irrigation and glycine as foliar spray.