The effect of spraying with gibberellin and the amino acid tecamine max on the growth of grafted Christi thorn seedlings

Introduction

Christi thorn L.is one of the evergreen fruits, Of the family Rhamanaceae, there are about 58 different genera with 3 main genera, which all come from different parts of the world where they are widely grown (Hauenschild et al., 2016) [21] . Of these, the most common and wellknown being the genus Sidr, whose original home believed to be southern Europe, southern International Journal of Agriculture and Food Science https://www.agriculturaljournals.com Asia (the Himalayas) and northern China; however, may also be found in northern Africa, Sudan and the Arab region (as far south as South America). Many areas in Iraq cultivate different varieties of sidr fruit; the first variety is found mostly in northern Iraq, the second is found mostly in southern Iraq, especially in Basra, the third is found mostly in the desert areas of southern and western Iraq, and the fourth is found in both the central and southern areas of Iraq (Al-Fadil, 2021; Al-Rubaie, 1998) [7,11] As a result of where people grow these kinds of fruits, there are many differences between the four types that exist. According to Verkleij (1992) [30] , marine algae are an effective source of organic materials for agriculture and act as a complement to chemical fertilizers, not a replacement. Marine algae also provide a variety of nutrients along with a group of plant growth regulators including gibberellins, auxins, and various amino acids that enhance both vegetative and root systems of plants. Marine algae can also help improve the quality and increase plant resistance to disease (Spinelli et al., 2010) [28] . When used properly, marine algae can promote improved plant growth by spraying algae onto the plant's total vegetative area (Kuwada et al., 2006) [25] and (Zodape et al., 2011) [32] . By adding marine algae (which contain amino acids) to some fruit seedlings (such as Sidr), the nutrients available to these plants in their soil have increased. This has also helped develop and strengthen the vegetative and root systems of these seedlings, while improving how much of the nutrition needed to support the leaves of these seedlings can be found therein (Al-Alaf, 2017) [4] . Marine algae based student extracts are examples of organic inputs for agricultural production; they can complement chemical fertilizers but cannot replace them. They provide a way to enhance and better utilize chemical fertilizers while also decreasing production costs. Worldwide there has been an average use of over 15 million tons of student based extracts per year across agricultural applications; many of them contain more than one class of plant growth stimulant (such as oxins, vitamins, and amino acids) andmost extracts contain many diverse saccharides; these can perform a variety of stimulating functions on plant life activities. Petaine is a nitrogen source at low levels and regulates osmosis at higher levels. The influence of these extracts on salinity and drought resistance in plants has been studied (Morales & Norrie, 2010) [26] . Spring (Al-Rubaie, 2011) [12] used marine algae extract (0, 100, or 125 ml/L), and depending on the type of olive (Olea Oeuropa), resulted in increased length of the main stem and root, dry weight, and chlorophyll in leaves, with 125 ml/L having the greatest effect. (Al-Obaidi, 2016) [9] researched using marine algae extract rata in Nepali olive trees at a lower concentration (20 ml). The study conducted with the use of tree-1 resulted in a significant increase in two seasons as measured by the area of paper as well as the chemical composition. In addition, Al-Dulaimi, Mohammaed and Ali (2016) confirmed that when applied to olive seedling of the variety Asharisi, the addition of Kelpak marine extract (in the concentrations of 0, 2, and 4 ML) resulted in a significant increase in almost all of the measured variables with the greatest effect of treatment being found at the 4 ML L-1 treatment where the length of main stem, number of branches, paper area, percentage of dry matter in the leaves and chemical content all increased significantly. Whereas the 2 ML L-1 treatment resulted in an increase in number of leaves and their chlorophyll content.

The comparison (0 ML) treatment had the lowest average values for many of the measured variables. According to Al-Qaisi (2018) [10] , the use of halwani and kamali grapes with marine extract Alga600 in grape plants has also improved performance in the kamali variety, with a concentration of 2 g/L demonstrating the best performance across many of the studied parameters for both root and vegetative growth. Performance measures included root system, leaf area, number of leaves, number of branches, leaf chlorophyll content, wet weight of leaves and dry weight of leaves. Growth regulators can be derived from either natural or synthetic processes. They are either naturally occurring plant hormone compounds or created ex vivo and encourage or alter certain physiological processes at certain concentrations in the organism. One group of compounds, referred to as phenolic compounds (metabolites with an oral ring system), have been shown to be very important for the overall growth and development of a plant, ultimately influencing stem elongation by modulating cellular division (cell division acceleration), altering the cell wall's capacity for expanding, controlling flowering induction, and influencing flowering (plant flowering), fruit development and ripening, seed germination, etc. Growth regulators have had significant impact on enhancing the quality of plant vegetative growth. The use of Jibriline as a plant growth regulator increases stem elongation through its ability to elongate plant cell walls; additionally, Jibriline will impact the quantity of flower branches produced thus contributing positively toward greater amounts of flowers and fruit being produced ultimately increasing the quantity of produce produced by a plant (Hartmann et al 2002) [20] . Several studies have shown that the use of seaweed extract can improve both the quality and yield of fruit crops such as apples, strawberries, almonds, grapes, kiwi, and apricots (Al-Saif et al 2023), (Abo-Zaid et al 2019) [2] . Other studies examining mango, grape and strawberry trees have shown that marine algae extracts when applied by way of foliar application, will improve the leaf area, nutrient levels, levels of vitamins, and provide fruits with greater quality (Al-Marsoumi et al 2020) [8] , (Abo-Zaid et al 2019) [2] . One of the major groups of plant hormones is gibberellins, consisting of many different gibberellins that stimulate plant growth along with over 135 different types of gibberellin. The most commonly used gibberellin is gibberellic acid (GA3) (Salman & Ali Wan, 2013) [23] . The effect of gibberellin on plant growth increases the length of the stem and increases the space between leaves by stimulating cell elongation and the ability of the plant to efficiently absorb nutrients, resulting in increased overall plant growth (Abu Zaid, 2000) [3] . Judge (2013) [24] found that applying gibberellic acid at two concentrations (0 mg. liter-1 and 100 mg. liter-1) to the leaves of olive seedlings produced by crossing the male with the female resulted in significantly increasing the diameter of the olive seedlings' main stems and also in the number of branches per seedling. (Abboud & ABD Aoun, 2013) [1] found that stimulating gibberellic acid application (500 mg. liter-1) on two varieties of olive trees (Al-Nabali and Al-Khudairi) stimulated nitrogen, phosphorus and potassium levels significantly more than non-treated trees, resulting in an average of 0.97% nitrogen (compared to 0.70% non-treated trees), 0.69% phosphorus (0.72% non-treated) and 0.74% potassium (0.54% nontreated) respectively). In a follow up study, (Ghazi & Mohamed, 2016) [27] reported that seedlings of carob were treated with gibberellic acid at concentrations of 0, 100, 200 and 300 mg. L-1) received a considerable increase in vegetative total dry weight (13.64g) and overall chlorophyll concentration in leaves (2.23g) as a result of the concentration level at 300 mg. Litre-1 with a total increase of 57.04% compared to control. The objective of the trial was to determine how spray treatment using seaweed and gibberellin would affect vegetative growth of sidr seedlings.

Materials and Methods

Research was carried out as part of the wooden canopy of the Department of Horticulture and Garden Engineering/Faculty of Agriculture, Samarra University for the duration of 1/10/2024 through 12/5/2025 to examine the relationship between the levels of seaweed (marine algae), GA3, and the vegetative qualities of grafted for the purpose of assessing the relationship between factors to promote healthy vegetable growth. The research used sidr trees that had been grafted at the age of 1; the trees were relatively equal in their growth 90-100 cm (height) and 9-6 mm (diameter) and were planted into 5 kg plastic planters.

Study Factors 2.The first factor:

The extract of marine algae (Tecamine Max) contains (a group of amino acids 14.40%, free amino acids 13%, organic nitrogen 8.0%, organic substance 50.0% and PH 6.6) fertilizer produced by a Spanish company and used a spray on the vegetative total in three concentrations: the comparison treatment (without addition) and its symbol is T 0 and 4 ml T 1 and its symbol is T 1 and 8 ml T 1 and its symbol is T 2 2.2.2. The second factor: spraying with Gibraltaric acid (GA3) in three concentrations: the comparison treatment (without addition) and its code is GA0 and 50 mgL-1 and its code is GA50 and 100 mgL-1 and its code is GA100. The spraying process was carried out on three dates, the first date 1/10/2024 and the second date 21 days after the first date and so on for the third date. The study was designed in a working trial using the R.C.B.D design of two-factor, three-repeat and two-breeders for each pilot. Thus, the number of seedlings used in the experiment (2 *3*3*3 = 54 seedlings) 2.2. The traits studied 2.2.1 Increase in seedling height (cm): Measured at the beginning and end of the experiment and extracted the difference between them using a tape measure from the grafting area to the top of the main stem of the seedling.

Vernier was used, above the grafting area at the beginning and end of the experiment and the differences between them were extracted.

Increase in the number of leaves for each seedling:

The number of leaves for each seedling and for each experimental one was calculated at the beginning and end of the experiment and the difference between them was extracted.

Number of secondary branches:

The number of secondary branches was calculated for each seedling and for each experimental one at the beginning and end of the experiment and the differences between them were extracted.

Number of main branches:

The number of main branches for each seedling and each experimental one was calculated at the beginning and end of the experiment and the differences between them were extracted.

The total chlorophyll content of the leaves was estimated based on the Goodwin method (Goodwin, 1976) [17] .

Nitrogen concentration was measured according to the method (Cresser & Parsons, 1979) [15] and on the Macrokjeldhal device.

The concentration of phosphorus was measured according to the method (Cresser & Parsons, 1979) [15] using a spectrophotometer at a wavelength of 420 nm.

The element potassium was estimated according to the method (Cresser & Parsons, 1979) [15] using the flame emission photometer.

The content of the leaves of carbohydrates was estimated according to the method of (Thimmaiah & Campus, 2004) [29] and using the Spectrophotometer on optical absorption 490 nm.

Statistical analysis:

The results were analyzed statistically using the computer within the SAS program and the averages of the transactions were compared using the Duncan polynomial test under the 5% probability level.

Result and Discussion

According to Figure (2 and 3), application of the marine algae extract resulted in significant differences. Results indicate the height of the plant and the diameter of its stem were significantly greater when treated with marine algae extract than not treated. The average amount of increase in plant height and plant stem diameter for the highest treatment (T 2 ) was 85.33 cm and 3.82 mm, respectively. The average height of the plant and diameter of the stem for the second highest treatment (T 1 ) was 79.67 cm and 3.40 mm, respectively. The lowest amount of increase in plant height and plant stem diameter occurred with no algae treatment (T 0 ); average values were 73.67 cm and 2.73 mm, respectively. In regard to the impact of GA (Gibberellic Acid), there are notable differences among various levels of GAs for height increase, (i.e., GA100 has the greatest increase with 91 cm and 3.75 mm consecutive), while the second best GA50 increased down to 78.67 cm and 3.47 mm respectively; however, GA0 has the lowest height increases at 69 cm (2.73 mm consecutive). The bilateral interaction of gibberellic acid and algae extracts had a large impact on height and circumference of each of the plants, T 2 GA100 treated plants have the largest increases in height and stem circumference (97 cm and 4.15 mm respectively) whereas the T 0 GA0 control group had the smallest growth. of 62cm, 2.0 mm in succession. The effect of spraying with marine algae extract and gibberelin acid growth regulator and the overlap between them in the rate of increase in plant height (cm) of sidr seedlings.

Fig 2:

The effect of spraying with marine algae extract and gibberelin acid growth regulator and the overlap between them in the rate of increase in the stem diameter (mm) of sidr seedlings.

The average number of leaves per sapling (fol.1-

The differences in leaf counts for the seeded plants compared to each test treatment were quantified on Table (5). T 2 Test Treatment yielded the highest number of leaves at 84.44, T 1 yielded the next most number of leaves at 69.33. Test treatment T 1 yielded the least amount of leaves at 61.33. Regarding how Jibriline acid functions as a growth regulator, the results presented in the table above indicate statistically significant differences between treatments as GA100 caused the most considerable increase with 82, GA50 caused a lesser yet significant increase of 73.67, and GA0 was the least effective resulting in an increase of just 59.44. The influence that the joint usage of a seaweed extract and a gibberellic acid plant growth regulator had on plant growth regarding leaf count was noted. For example, the highest average leaf count per plant of 97 leaves was observed in the T 2 GA100 treatment, while the lowest average leaf count of 50 leaves per plant was seen in the T 0 GA0 treatment.

Fig 3:

The effect of spraying with marine algae extract and gibberelin acid growth regulator and the overlap between them in the rate of increase in the number of total leaves (folio. Seedling -1 ) for Sidr Seedlings.

The rate of the number of main and secondary branches per seedling (branch. 1-

The figures in ( 6) indicate how many branches there were per seedling, and that differences in the number of main and secondary branches (T 3 ) increased with the use of the plant growth regulator jasmonic acid. The transactional group (T 4 ) produced the most branches, producing 5.3 of each type of branch in one transaction, while there was a statistically significant difference in the number of either of the two branch types produced in the other transaction groups.

The statistical analyses shown previously in this table indicate significant differences as a result of applying the gibberellin acid growth regulator, with the GA100 treatment having the highest branch counts at 5.0 and 9.0 main and secondary branches (saplings -1) in succession. The second highest treatment was the GA50 treatment with average branch counts (saplings -1) of 3.67 and 7.0 branches, respectively. The GA0 treatment had the lowest average branch counts at 2.33 and 3.67 (saplings -1) in succession. Regarding a bilateral overlap for both elements of the experiment, the results presented in figure (6) indicate that there are significant differences in the number of main and lateral branches over many weeks following the application of T 2 GA100 and T 0 GA0 at different rates of branch growth.

The treatment (T 2 GA100) produced the highest average number of main and lateral branches after both applications (7 branches on seedling 1 and 12 branches on seedling 1) and was significantly greater (p< 0.05) than treatment (T 0 GA0) which resulted in the lowest average number of main and lateral branches (1 branch on seedling 1 and 2 branch on seedling 1).

Fig 4:

The effect of spraying with marine algae extract and gibberelin acid growth regulator and the overlap between them in the rate of increase in the number of main branches (Branch. Seedling -1 ) for Sidr Seedlings.

Fig 5:

The effect of spraying with marine algae extract and gibberelin acid growth regulator and the overlap between them in the rate of increase in the number of secondary branches (branch. Seedling -1 ) for Sidr Seedlings.

The application of Marine Algal Extract (Algae) and Gibberellic Acid (GA3) to the Sidr leaves significantly increased total chlorophyll levels at the 0.05 significance level, as illustrated in Table (1).

As the concentration of gibberellin growth regulator increases, there was a corresponding increase in the mean total chlorophyll content. At a concentration of GA2 (100 mg.1litre), the mean total chlorophyll was 4.42 mg.gram-, compared with GA1 (3.52) and GA0 (2.54). In addition, there was an increase in the mean total chlorophyll in T 2 at an algae extract concentration of (8 mg. litre-1) to 4.00 mg.gram-1, compared with T 1 (3.44) and T 0 (3.04). The two experimental factors exhibit a strong impact on determining how much total chlorophyll was formed from overlapping each other, as evidenced by substantial differences between them (i.e., T 2 GA100=5.45 mg 1 g total dry weight vs. T 0 GA0; 2.12 mg ga g total dry).

Table 1: The effect of spraying with marine algae extract and growth regulator gibberelin acid and the overlap between them in the leaf content of chlorophyll (mg. .42 a * The averages of each group followed by different letters indicate significant differences between them at the 5% probability level according to the Duncan polynomial test

Nitrogen, Phosphorus and Potassium

Table (2, 3 and 4) shows the results of the effect of spraying with marine algae extract and gibberelin acid (GA3) and the overlap between them in the percentage of nitrogen, phosphorus and potassium in the leaves of the Sidr plant (%). The results showed significant differences between the coefficients as a result of spraying with algae extract, achieving a concentration of T 2 (8 mg.liters)the highest average of 1.31, 0.24, and 1.10 in succession, while the lowest was at T 0 at 1.18, 0.18, and 1.01% in succession. Nitrogen also rose with increased gibberelin concentrations, reaching the highest average at GA2 (100 mg.liters) by 1.31,0.23, and 1.12% respectively, followed by a significant difference GA1 by 1.31,0.20, and 1.07% respectively, while the lowest average was recorded at GA0 at 1.17, 0.19, and% respectively. The highest percentage of nitrogen was recorded when treating the interference between marine algae extracts at a concentration of 8 mg.1 litre (T 2 ) and 100 mg gibberelin.liters(GA2), reaching 1.42%, 0.26, and 1.17respectively, a value that was morally superior to most other transactions.

Percentage carbohydrates

Table (5) This paper discusses the results of the effects of using marine algae extract and gibberellic acid (GA3) as growth regulators on the carbohydrate content in leaves of Sidr plants. Statistically significant differences were found by spraying with marine algae extract and GA3 to obtain the highest carbohydrate percentage of 5.42%. This was achieved by using the marine algae extract at a concentration of 8 mg:1 L (T 2 ) and GA3 at a concentration of 100 mg:1 L (GA2); these two treatments produced the highest mean carbohydrate content out of all treatments. Treatment GA2 × T 1 had a significantly higher mean carbohydrate content than treatment GA0 × T 0 (4.55% and 3.12%, respectively). There was an increase in carbohydrate content with increasing gibberellin levels with an average of 4.65% carbohydrate content for GA2, compared to 4.07% for GA1 and 3.23% for GA0. There was also a noticeable effect from algae extract as T 2 yields were 4.53% when compared to T 1 at 4.12% and T 0 at 3.30%.

Interpretation of results

The results in Figures ( 12345) and the accompanying tables showed that there are clear significant differences in the vegetative and chemical qualities of sidr seedlings when treated with marine algae extract and growth regulator gibberelin acid (GA), either individually or by overlapping between them. These differences included vegetative features such as plant height, stem diameter, number of leaves, and number of main and secondary branches, as well as chemical qualities such as increased leaf content of chlorophyll, nutrients (N, P, K), and carbohydrates. At the vegetative trait level, the results (Figures 12345) showed that the treatment T 2 GA100, representing the overlap between the highest concentration of algae extract (8 mg.1litre) and the highest concentration of gibberellin (100 mg.litre), has achieved the highest values in all vegetative qualities, with a plant height of 97 cm, a stem diameter of 4.15 mm and a leaf count of 97 leaves. Sapling ा ¹, and the number of main and secondary branches 7.0 and 12.0 branches. Saplingin succession. While the comparison transaction T 0 GA0 recorded the lowest values in all indicators. This improvement is attributed to the synergistic effect between algae extract compounds containing natural growth stimulants (oxines, cytokines, gibberellins) and micronutrients, and between gibberellin's ability to stimulate division and cell elongation. As for the chemical qualities of the leaves of the plant (Tables 12345), the treatment T 2 GA2 also outperformed in all chemical indices, recording the highest total chlorophyll content (5.45 mg). g¹), nitrogen (1.42%), phosphorus (0.26%), potassium (1.17%), and carbohydrates (5.42%). These increases were accompanied by a significant rise in the averages of the single coefficients of algae extract and gibberelin, indicating their role in enhancing the absorption of elements and increasing the efficiency of photosynthesis.

These findings are consistent with what (Al-Bakar et al., 2020) [5] found that marine algae extracts contain biostimulant compounds that contribute to improving the growth and physiological qualities of the plant. The study of (Guo et al., 2022) [18] also showed that gibberelin promotes cell division and elongation and improves representational performance. (Colla et al., 2014) [14] show that marine algae extracts stimulate the gene expression of enzymes associated with the uptake of macronutrients such as nitrogen and phosphorus.

Conclusion

In the same context, the study of (Gupta & Sharma, 2023) [19] indicated that double spraying with marine algae extract and gibberelin in artichoke led to significant increases in the number of branches and leaf content of elements. (El-Awadi et al., 2022), (Zhang et al., 2019) [16,31] showed that Ascophyllum nodosum extract contains compounds that regulate plant hormones and improve the uptake and distribution of elements within plant tissues.

Conflict of interest

The authors declare no conflicts of interest associated with this manuscript.

Acknowledgement

AcknowledgmentsThe authors gratefully acknowledge the staff of the Department of Horticulture College of Agriculture Tikrit University and Department of Horticulture and Department of Food science College of Agriculture Samarra University for their technical and general support.

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