Comparison of Twenty Selected Fenugreek Genotypes Grown under Irrigated and Dryland Conditions: Morphology, Yield, Quality Properties and Antioxidant Activities

Abstract

In this study, 18 fenugreek genotypes and two cultivars were cultivated under irrigated and dryland conditions to determine the morphological, yield, quality, and bioactive properties. The morphological and seed yield values showed differences among the fenugreek genotypes and cultivars. The PI 286532 and PI 639185 genotypes for total alkaloid content and the PI 426973 and PI 572538 genotypes for trigonelline content were prominent under both irrigated and dryland conditions. The PI 215615 and PI 286532 genotypes were found to be rich in fixed oil contents under two growing conditions, while all fenugreek genotypes had high linoleic contents. The PI 568215 and PI 251640 genotypes and the gürarslan cultivar had the highest antioxidant activity compared with the other genotypes. The PI 215615 and PI 302448 genotypes and the gürarslan cultivar were found to be superior with respect to phenolic and flavonoid contents. Generally, the cluster analysis clustered the genotypes into two main groups and two sub-groups. Group B included more than 66% of the genotypes and cultivars. The biplot analysis accounted for over 53% of total variations. As a result of this study, most of the genotypes were found to be high in the examined properties, and these genotypes were good sources of natural components with potential applications in the food and pharmaceutical industries.

1. Introduction

Increasing temperatures caused by climate change are making already dry areas drier and humid areas more humid. In arid regions, this means that water evaporates faster when temperatures rise, thus increasing the risk of drought or prolonging drought periods. Plant yield and quality are adversely affected in water-deficit environments. To overcome these problems, it is necessary to apply the right water management systems in dry agricultural conditions to ensure that plants can be grown economically [1]. In addition, it is important to identify plants with high adaptability to changing climatic conditions. Among such plants with high adaptability is fenugreek (Trigonella foenum-graecum L.), which belongs to the Fabaceae family and is widely accepted as an antidiabetic and anticholesterol plant. It holds an important place as a high-quality forage legume, and it can be used as a nitrogen-fixing cover crop and green manure in agricultural field areas; additionally, it possesses high medicinal, pharmaceutical, and nutraceutical properties [2,3,4,5].

Fixed oil is one of the most important seed quality properties of fenugreek. It contains saturated and unsaturated fatty acid compositions. In fact, fenugreek seed oil is rich in terms of unsaturated fatty acid composition (more than 80% of fatty acid) as oleic, linoleic, and linolenic acids [6]. It has been found that a fenugreek oil blend is a high-quality cooking oil with combinations of n-6 and n-3 fatty acids [7]. Also, dietary fatty acids (especially poly- and monounsaturated fatty acids) alter the plasma lipoprotein profile and decrease cardiovascular disease risks [8]. Similarly, the oil of fenugreek includes ω-3, ω-6, and ω-9 fatty acids, along with many saponins, alkaloids, and sterols. It serves as a proestrogen source and obstructs intestinal absorption [9]. Moreover, the fixed oil of fenugreek can be used in cosmetics and hair styling [10].

The seeds of fenugreek contain the most important alkaloid component of trigonelline; indeed, this component plays a critical role in medicinal effects [5]. It has been reported that trigonelline can be utilized in diabetes, as it has cholesterol-lowering, anti-carcinogenic, antiseptic, hypoglycemic, and hypocholesterolemic properties [11,12,13].

Nowadays, interest in natural antioxidants produced from many types of fruits, seeds, grains, vegetables, and plants has increased [14,15,16]. Natural antioxidants are well known for their protective capacity against free radical attacks in living organisms and cells [17]. Resultantly, they may prove advantageous over synthetic antioxidants because they do not contain chemicals; they have also been part of the human diet for thousands of years [18]. Fenugreek is one of the most important plants that has high antioxidant activities.

The use of genetic diversity to obtain a sustainable yield in dryland conditions with water deficiency is a well-practiced crop development strategy [19]. Many previous studies on fenugreek have been carried out on different-origin genotypes or local cultivars. However, this particular study was conducted to determine some important chemical properties of overseas-origin fenugreek genotypes and cultivars. Therefore, we were encouraged to test the hypothesis that a detailed phytochemical investigation of fenugreek genotypes of different origins is possible if grown under the same environmental (irrigated and dryland) conditions. The other hypothesis was that variations in chemical components such as alkaloid, trigonelline, phenolic, and flavonoid contents and fatty acids, compared separately under irrigated and dryland conditions, have the potential to enhance the nutraceutical qualities of this crop. For this reason, the seeds of fenugreek genotypes employed in this study were selected from different-origin fenugreek genotypes grown in 2017 (88 genotypes) and 2018 (77 genotypes) [20,21].

The 18 promising genotypes, selected depending on the seed yield of fenugreek grown in the years 2017 and 2018 and originating from nine different countries (Turkey, Ethiopia, India, Iran, Pakistan, Egypt, Australia, Bulgaria, and Armenia), and two cultivars (gürarslan and çiftçi) were cultivated under irrigated and dryland conditions. Detailed chemical analysis of the fatty acids and ethanolic extracts was performed. So, this study can be considered the first extensive research on some of the chemical properties of fenugreek genotypes and cultivars grown under irrigated and dryland conditions. Furthermore, it is useful to find the best-performing genotypes that can be used as advanced selection materials for breeding programs.

2. Materials and Methods

2.1. Plant Material and Experimental Design

This study was conducted during the 2017–2020 growing seasons at Bolu Abant Izzet Baysal University, Bolu, Türkiye. The experimental material comprised fenugreek genotypes obtained from different geographical regions of the world. One hundred and eighteen fenugreek genotypes received from the United States Department of Agriculture (USDA) with two commercial cultivars (gürarslan and çiftçi) were used in 2017, and these cultivars were developed through single-plant selection, had resistance to various diseases, and were used as standard cultivars. Based on the adapted 88 genotypes in 2017, 77 genotypes were selected and sown in the 2018 vegetation period according to Augmented Trial Design. In this study, eighteen fenugreek genotypes obtained from the USDA with two local fenugreek cultivars (gürarslan and çiftçi, obtained from Transitional Zone Agricultural Research Institute and Ankara University, respectively) were used in the 2019–2020 experimental years (

Table 1. The fenugreek genotypes and cultivars used in this study.

No	Accession Code	Country	Collection Site	No	Accession Code	Country	Collection Site
1	Çiftçi *	Türkiye	Türkiye	11	PI 381062	Iran	Ghazvin
2	Gürarslan *	Türkiye	Türkiye	12	PI 426971	Pakistan	Gujjo, Karachi
3	PI 173820	Türkiye	Malatya	13	PI 426973	Pakistan	Mirpur Batoro
4	PI 194020	Ethiopia	Debra Markos	14	PI 469264	Egypt	Nile Delta
5	PI 215615	India	Sirsa, Punjab	15	PI 568215	Türkiye	-
6	PI 251640	Ethiopia	-	16	PI 572538	Egypt	Nubaria, North Delta
7	PI 286532	India	Kulu bazaar	17	PI 613633	Australia	-
8	PI 296394	Iran	-	18	PI 617076	Bulgaria	-
9	PI 302448	India	Delhi, India	19	PI 639185	Armenia	Yerevan
10	PI 302449	India	-	20	PI 660995	Armenia	Yerevan

* Local fenugreek cultivars.

).

The field experiments were conducted at the research and application area of Bolu Abant İzzet Baysal University, Bolu, Türkiye (40°44′44″ N, 31°37′45″ E, 806 m above sea level) in 2019 and 2020. Climatic data from sowing to harvest (between April and August) were recorded between 8.30 and 19.50 °C for temperature, 25.60 and 138.60 kg/m² for precipitation, and 70.60 and 80.90% for relative humidity in 2019, and between 8.7 and 21.8 °C for temperature, 0 and 142.6 kg/m² for precipitation, and 56.1 and 76.7% for relative humidity in 2020 [22].

The experimental area soil properties were found as clayey, pH 7.56, 3.71% organic matter, 0.52 kg/ha phosphorus, 1083.08 kg/ha potassium, and 0.0383% salty. This study was carried out with a split-block design with three repetitions in the 2019 and 2020 growing seasons. Different genotypes and cultivars were used as the main plot in blocks, and growing conditions were used as the sub-parcel. In both experimental years, seeds were sown directly by hand on irrigated and dryland conditions on 14 April 2019–2020 each consisting of 4 m long rows, where row width and intra-row spacing were 30 and 10 cm.

While irrigation was performed every 2–3 days in irrigated areas, no irrigation was applied in dryland areas during the vegetation period. In the experiment, 60 kg/ha diammonium phosphate (DAP) as a base fertilizer and 40 kg/ha ammonium sulfate (AS) as a top fertilizer were applied.

During the vegetation period in the experimental years, all required agricultural practices were conducted. The harvests of the fenugreek genotypes and cultivars were carried out between 27 July and 11 August and between 30 July and 18 August under irrigated and dryland conditions in the experimental years, respectively. The moisture contents of the fenugreek seeds were determined according to a report by [23]. The moisture contents of fenugreek seeds were measured to be between 10% and 14% under irrigated and dryland conditions [24]. In this study, seeds of fenugreek genotypes and cultivars obtained from the vegetation period of 2020 were used for the analyses.

2.2. Total Alkaloid Content Extraction

The total alkaloid content in fenugreek genotypes and cultivars was determined according to [25]. Ground fenugreek seeds (3 g) were mixed with 25 mL of sulfuric acid (10%) and 5 mL of distilled water and shaken. The final volume was made up to 25 mL with distilled water. The extraction was filtered, and 20% ammonium hydroxide (NH₄OH) was added until pH = 8–9. Then, the extraction process was carried out by adding 50 mL of chloroform. The filtrate was evaporated in a water bath to obtain a dry residue and the total alkaloid content was calculated by the following formula:

A = (Wt − W0)/We × 100 (%)

A: total alkaloids; Wt: total weight (capsule weight and alkaloid weight); W0: empty capsule weight; We: sample weight.

2.3. Trigonelline Content Extraction and UHPLC Analysis

Trigonelline extraction of the fenugreek genotypes and cultivar seeds was performed using a modified version of the method described by [26].

Fenugreek seeds were ground in a mortar with 80% methanol and magnesium oxide. After incubation at 60 °C and 30 min, the homogenates were centrifuged and the supernatants were collected. After the methanol was completely evaporated, the extracts dissolved in methanol were dissolved in pure water. Samples were filtered using a disposable syringe and filter unit, and aliquots were used to determine the amount of trigonelline by HPLC. The trigonelline content was determined by an ultra-high-performance liquid chromatography system (Thermo Fisher Dionex Ultimate 3000) with a DAD detector and a Strategy C18 hypersil gold column (150 mm × 2.1 mm, 1.9 μm). Using a methanol/water mixture (50.50 v/v) as the mobile phase, the pH of the solution was adjusted to 5 with 50 mM sodium acetate. Detection was performed at 268 nm by the UV detector, setting the elution in isocratic mode at a flow rate of 1 mL/min. Trigonelline content was identified by comparison of retention times to a standard under identical analysis conditions. All the standard and sample solutions were injected in triplicate. Before performing the HPLC analysis, a calibration curve was generated using the appropriate trigonelline concentration in the mobile-phase medium.

2.4. Isolation of Fixed Oil Content (%)

The fixed oil contents of the seeds of different fenugreek genotypes and cultivars were determined according to a report by [27]. Dried fenugreek seeds (25 g) were ground and extracted at 60 °C by a Soxhlet extractor for 8 h, using the solvent n-hexane. After 8 h, the fixed oil and solvent were separated by a rotary evaporator. The oil content was weighed to determine the lipid content and then transferred to brown glass vials and stored at −20 °C until further analysis. The fixed oil contents of seeds were determined on a dry weight basis and expressed as percentages.

2.5. Determination of Fatty Acids (%)

Methyl esters of fatty acids (FAMEs) were prepared according to [28]. The Shimadzu GC-2010 gas chromatograph (Shimadzu Corporation, Tokyo, Japan) was used for the fatty acids of fenugreek genotypes and cultivars with a flame ionization detector (FID) and an Rtx-2330 capillary column (60 m × 0.25 mm) with a thickness of 0.2 μm. The detector temperature was set at 240 °C. GC oven temperature was kept at 140 °C for 5 min initially. Afterward, the temperature was raised up to 260 °C at a rate of 4 °C/min and kept constant at 260 °C for 20 min. Helium was used (1 mL/min) as a carrier gas. The FAMEs were determined by comparing retention times with reference standards (mixture FAME Mix, SUPELCO, which included 37 FAMEs). Methyl-undecanoate (Sigma Aldrich Chemical Co., St. Louis, MO, USA) was used to determine FAME quantity as the internal standard. The obtained total results from FAMEs were revealed as percentages.

2.6. Seed Extraction of Fenugreek Seeds

Seed extractions of fenugreek genotypes and cultivars were carried out according to the report by [29] with some modifications. A total of 10 g of fenugreek seeds was ground and subjected to ultrasonic vibration with 80% methanol at 30 °C for 60 min. Then, filtration was performed and 80% methanol was added to the remaining sample, which was made up to 100 mL. Samples were stored at +4 °C until analysis.

2.7. DPPH Method

The radical-scavenging activity of fenugreek seed methanol extract rich in phenolic content was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay [30]. A 1 mL amount of extract sample was mixed with 2 mL of DPPH radical solution (1 mg of DPPH resolved in 100 mL of methanol). After thorough mixing and incubation at room temperature for 5 min, the absorbance values (Δ517 nm) were determined with a spectrophotometer. As a control, 2 mL of DPPH solution was dissolved in 1 mL of distilled water. The free radical-scavenging activity was calculated using the following equation:

RSA (%) = (Δ517 nm control − Δ517 nm sample)/Δ517 nm control) × 100

2.8. FRAP Method

The FRAP method was conducted according to [31]. Briefly, 300 mM acetate buffer FRAP reagent (pH:3.6; 3.1 g sodium acetate trihydrate + 16 mL glacial acid distilled water 1:1); 10 mM 2,4,6-tris (2-pyridyl)-striazine (TPTZ) in 40 mM HCl; and 20 mM iron(III) chloride hexahydrate (FeCl₃*6H₂O) were prepared at a ratio of 10:1:1 to provide the working reagent. Then, 1 mL of active FRAP was added to 100 μL of fenugreek extract, and after waiting for 30 min, absorbance values were determined in a spectrophotometer at a 595 nm wavelength. To approximate the activity capacity of the sample, a Trolox calibration curve (TE) was constructed and the results were recorded as mg TE (mg TE/100 g) per 100 g of Trolox of the seed sample.

2.9. Total Phenolic Content

The total phenolic contents of fenugreek seeds were determined according to a report by [31]. First, 0.4 mL of distilled water and 0.5 mL of diluted Folin–Ciocalteu reagent were added to 100 µL of fenugreek seed extract. After incubating these extracts for 5 min, 1 mL of 7.5% sodium carbonate (w/v) was added. Absorbances were measured at 765 nm using a spectrophotometer after 2 h. The calibration curve of gallic acid (GA) was used to estimate the sample activity capacity. The results were recorded in mg GA equivalent (mg GAE/100 g) per 100 g of seeds.

2.10. Total Flavonoid Content

The total flavonoid contents of fenugreek seeds were determined according to a report by [32]. In total, 1 mL of extract, 4 mL of distilled water, and 300 µL of sodium nitrite (NaNO₂) (0.3%) were mixed, and the mixture was shaken for five minutes. Then, 300 µL of aluminum chloride (AlCI₃) (10%) and 200 µL of 1 M NaOH were added to this mixture and mixed well. In the last stage, 2.4 mL of distilled water was added and agitation was performed. The absorbances of the total flavonoid contents were determined at 510 nm. Quercetin compound (QE) was used as a standard to determine the total amount of flavonoids and results are reported as mg QE/100 g dry seeds.

2.11. Statistical Analysis

Statistical analysis of the experimental data was conducted with the JMP statistical program. Differences between the mean values were compared by LSD (least significant difference) at a 5% probability level. Biplot analysis was carried out to determine the relationships between the examined properties of fenugreek genotypes and cultivars. Cluster analysis was performed to determine the genetic differences among the fenugreek genotypes based on the standardized data to use a measure of Euclidean distance and the Ward minimum variance method with the hierarchical clustering analysis, and the distances among the fenugreek genotypes were determined by using the JMP-13 statistical program.

3. Results

3.1. Plant Height, Branch Number, and Seed Yield

The plant heights of the fenugreek genotypes and cultivars were significantly affected by the different growing conditions. Similarly, the genotypes and cultivars showed statistical differences when grown under the same conditions in 2019 and 2020. The highest plant height (79.50 cm) was noted from the PI 426973 genotype in 2020 under irrigated conditions while the lowest plant height (31.23 cm) was found from the PI 617076 genotype (

Table 2. Plant height, branch number, and seed yield of fenugreek genotypes and cultivars.

No	Genotypes/ Cultivars	Plant Height (cm)				Branch Number				Seed Yield (kg/da)
		2019		2020		2019		2020		2019		2020
		IR	DRY	IR	DRY	IR	DRY	IR	DRY	IR	DRY	IR	DRY
1	Çiftçi	53.50 cde	48.87 d–ı	67.80 a–d	53.43 e–m	3.73 abc	3.03 a–f	4.07 b–e	2.93 g–m	58.77 b–f	58.92 b–f	81.26 a–ı	79.78 a–ı
2	Gürarslan	49.43 d–ı	42.33 h–l	56.13 c–ı	45.23 ı–p	3.50 a–d	2.77 b–f	3.87 b–f	2.40 l–o	63.64 b–f	69.60 b–f	62.36 a–ı	78.93 a–ı
3	PI 173820	44.03 f–k	34.23 lm	54.73 d–k	42.30 j–q	3.10 a–f	2.53 c–f	4.03 b–f	2.27 mno	63.01 b–f	42.06 def	43.79 f–ı	38.55 ı
4	PI 194020	46.30 e–k	43.97 f–k	55.13 c–j	37.13 pq	3.23 a–f	3.07 a–f	3.33 d–j	2.30 mno	37.74 ef	71.24 b–f	55.27 c–ı	44.68 f–ı
5	PI 215615	55.10 bcd	51.03 d–g	63.27 b–f	47.27 h–p	3.03 a–f	2.47 c–f	4.13 a–d	1.87 no	85.39 b–f	67.00 b–f	93.59 a–e	76.42 a–ı
6	PI 251640	56.57 bcd	49.17 d–ı	64.27 b–e	50.87 e–o	3.53 a–d	3.50 a–d	4.63 ab	2.67 ı–o	51.99 b–f	65.09 b–f	64.45 a–ı	79.34 a–ı
7	PI 286532	48.17 d–j	38.20 klm	55.77 c–j	38.90 n–q	3.50 a–d	3.03 a–f	3.27 e–k	2.40 l–o	59.73 b–f	34.82 ef	58.00 b–ı	61.80 a–ı
8	PI 296394	50.23 d–h	41.73 h–l	62.07 b–g	45.10 ı–p	4.03 ab	3.20 a–f	3.53 d–h	2.40 l–o	63.75 b–f	43.94 def	54.97 d–ı	86.38 a–h
9	PI 302448	54.40 cde	42.80 g–l	50.80 e–o	43.57 ı–q	3.37 a–e	3.37 a–e	4.93 a	2.07 no	73.80 b–f	58.46 b–f	62.88 a–ı	42.65 ghı
10	PI 302449	38.42 klm	34.73 lm	42.43 j–q	40.10 m–q	4.10 a	3.13 a–f	4.47 abc	2.70 h–n	62.73 b–f	59.34 b–f	47.09 f–ı	48.14 e–ı
11	PI 381062	40.27 j–m	34.77 lm	55.03 c–j	37.27 opq	3.50 a–d	2.93 a–f	3.77 c–g	2.43 k–o	64.62 b–f	41.62 def	89.47 a–f	46.88 f–ı
12	PI 426971	53.10 cde	41.43 ı–l	48.80 g–p	41.23 k–q	2.77 b–f	2.53 c–f	2.93 g–m	1.83 o	87.95 a–e	50.58 c–f	44.84 f–ı	70.16 a–ı
13	PI 426973	59.70 abc	54.00 cde	79.50 a	52.27 e–n	3.50 a–d	3.03 a–f	4.47 abc	2.33 mno	105.78 ab	61.39 b–f	87.48 a–g	86.10 a–h
14	PI 469264	51.67 c–f	44.03 f–k	56.40 c–ı	40.87 l–q	2.87 a–f	3.17 a–f	3.53 d–h	1.97 no	50.42 c–f	51.93 b–f	61.73 a–ı	56.46 c–ı
15	PI 568215	68.03 a	54.30 cde	72.23 ab	46.37 ı–p	3.17 a–f	2.93 a–f	3.77 c–g	2.20 mno	142.02 a	85.62 b–f	99.85 a–d	107.17 a
16	PI 572538	49.70 d–ı	39.10 klm	48.20 h–p	44.63 ı–q	2.70 c–f	2.20 ef	2.53 j–o	2.67 ı–o	39.79 def	31.14 f	41.13 hı	42.28 ghı
17	PI 613633	46.17 e–k	39.27 klm	60.77 b–h	39.03 n–q	2.37 def	2.00 f	3.20 f–l	2.00 no	77.07 b–f	32.93 ef	54.22 d–ı	45.10 f–ı
18	PI 617076	53.60 cde	32.57 m	50.83 e–o	31.23 q	2.36 def	2.33 def	2.37 l–o	2.13 mno	101.78 abc	141.37 a	84.58 a–ı	77.72 a–ı
19	PI 639185	67.67 a	40.20 j–m	68.60 abc	50.23 f–p	2.57 c–f	2.13 ef	3.40 d–ı	2.50 j–o	77.14 b–f	50.05 c–f	101.37 abc	105.52 a
20	PI 660995	63.40 ab	55.57 bcd	73.20 ab	54.50 d–l	3.67 abc	2.77 b–f	3.73 c–g	2.53 j–o	94.82 a–d	79.92 b–f	103.83 ab	95.58 a–d
Cultivar mean		51.47	45.60	61.97	49.33	3.62	2.90	3.97	2.67	61.21	64.26	71.81	79.36
Genotype mean		52.58	42.84	59.00	43.49	3.19	2.80	3.67	2.29	74.42	59.36	69.36	67.27
General mean		52.47 a	43.12 b	59.30 a	44.08 b	3.23 a	2.81 b	3.70 a	2.33 b	73.10 a	59.85 b	69.61 ns	68.48 ns
Fgenotype		10.56 *		4.69 *		1.93 *		3.49 *		2.44 *		3.00 *
Fapplication		97.35 *		101.62 *		9.08 *		215.97 *		4.71 *		0.05 ns
Fgenotype×application		1.98 *		0.94 *		0.28 *		2.66 *		0.81 *		0.51 *

IR: irrigated conditions; DRY: dryland conditions; *: significant at 5% level; ns: not significant. Values (genotype × irrigated and dryland condition interactions) within the years shown with the same letters are not significant according to the least significant difference test at the 5% level. *: Significant at the 5% level.

). Mean plant height values of fenugreek genotypes and cultivars grown under irrigated conditions were found to be higher than in dryland conditions. In 2019, while the mean plant height values of fenugreek varieties (çiftçi and gürarslan) were found to be higher than six genotypes grown under irrigated conditions, they were higher than eight genotypes grown under dryland conditions. In 2020, plant height values of fenugreek cultivars were higher than nine genotypes grown under irrigated conditions and twelve genotypes under dryland conditions. In addition, the plant height values of the çiftçi cultivar were found to be higher than the gürarslan cultivar in both years of the experiments.

The branch number values of the fenugreek genotypes and cultivars showed significant differences under irrigated and dryland conditions. The branch number was higher under irrigated conditions compared to dryland conditions. So, it can be revealed that the branch number of fenugreek can increase with irrigation. The highest branch number was found from PI 302448 in 2020 grown under irrigated conditions, while the lowest number of branches was recorded from the PI 426971 genotype with 1.83 branches/plant (Table 2). Generally, except for some genotypes, the branch number values were higher in 2019 than in the 2020 vegetation period. This situation supports the opinion that irrigation is an important factor in increasing the number of branches in fenugreek genotypes and varieties, with the amount of precipitation falling in the vegetation period of 2019 being higher than in 2020. Compared to the branch number values of fenugreek genotypes and cultivars, the PI 251640 genotype has come to the fore in terms of branch number under irrigated and dryland conditions in both 2019 and 2020.

3.2. Total Alkaloid and Trigonelline Contents

Significant differences were found among the fenugreek genotypes and cultivars for total alkaloid contents under irrigated and dryland conditions. The total alkaloid contents changed between 1.43 and 2.70% and between 1.13 and 2.60% under irrigated and dryland conditions, respectively (

Table 3. Total alkaloid content and trigonelline of fenugreek genotypes and cultivars.

No	Genotype/Cultivar	Total Alkaloid Content (%)		Trigonelline Content (%)
		Irrigated	Dryland	Irrigated	Dryland
1	Çiftçi	2.33 O	2.14 V	0.46 abc	0.34 b–m
2	Gürarslan	2.43 K	2.10 Y	0.34 c–m	0.29 g–m
3	PI 173820	2.33 O	1.75 h	0.43 a–e	0.30 f–m
4	PI 194020	1.80 e	2.16 U	0.25 j–m	0.46 abc
5	PI 215615	1.80 e	2.10 Y	0.23 m	0.33 d–m
6	PI 251640	1.76 g	2.34 N	0.23 m	0.31 e–m
7	PI 286532	2.70 A	2.40 L	0.38 a–ı	0.37 a–j
8	PI 296394	2.27 R	2.60 D	0.32 d–m	0.42 a–f
9	PI 302448	2.43 J	2.60 D	0.24 klm	0.46 abc
10	PI 302449	2.10 Z	1.50 l	0.26 ı–m	0.24 klm
11	PI 381062	2.47 H	1.85 d	0.28 g–m	0.29 g–m
12	PI 426971	1.60 k	1.13 o	0.27 h–m	0.33 d–m
13	PI 426973	1.43 m	2.03 b	0.40 a–g	0.48 a
14	PI 469264	2.52 F	2.33 O	0.46 abc	0.36 a–k
15	PI 568215	2.64 B	1.70 j	0.23 m	0.39 a–h
16	PI 572538	2.50 G	1.97 c	0.43 a–d	0.44 a–d
17	PI 613633	2.21 T	2.25 S	0.28 h–m	0.37 a–j
18	PI 617076	1.73 ı	1.41 n	0.37 a–j	0.35 b–l
19	PI 639185	2.61 C	2.40 L	0.40 a–g	0.34 b–m
20	PI 660995	2.46 I	2.30 Q	0.28 g–m	0.38 a–ı
Cultivar mean		2.38	2.12	0.40	0.32
Genotype mean		2.19	2.04	0.32	0.37
General mean		2.21 a	2.05 b	0.33 b	0.36 a
Fgenotype		3742560.42 *		3.10 *
Fapplication		4156380.01 *		6.93 *
Fgenotype×application		1633692.48 *		2.65 *

*: significant at 5% level. The values between the applications (irrigated and dryland conditions) marked with the same letters are not significant according to the least significant difference test at the 5% level. *: Significant at the 5% level.

). The highest total alkaloid content was found in the PI 286532 genotype, followed by the PI 568215 and PI 639185 genotypes, under irrigated conditions, while the lowest total alkaloid content was noted in the PI 426973 and PI 426971 genotypes under irrigated conditions. The highest total alkaloid contents were observed in the PI 296394 and PI 302448 genotypes, and the lowest contents were obtained from PI 426971 and PI 617076 under dryland conditions. According to our study, the USDA genotypes were higher in their total alkaloid content in comparison with the local genotypes.

The trigonelline contents in seeds of different fenugreek genotypes and cultivars grown under irrigated and dryland conditions are presented in Table 3. Significant differences were found among fenugreek genotypes and cultivars in terms of trigonelline contents. The trigonelline contents in different fenugreek genotypes and cultivars were between 0.23 and 0.46% under irrigated conditions, and it was observed between 0.24 and 0.48% under dryland conditions.

Under irrigated conditions, trigonelline content ranged from a minimum of 0.23% in PI 215615, PI 251640, and PI 568215 genotypes to a maximum of 0.46% in the çiftçi cultivar and the PI 469264 genotype, while it ranged from 0.24% in genotype PI 302449 to 0.48% in the PI 426973 genotype under dryland conditions.

The accumulation of mean trigonelline content in the irrigated and dryland conditions in this study was slightly elevated from 0.33% under irrigated conditions to 0.36% under dryland conditions (Table 3).

Seven genotypes and two cultivars were found with above-mean values, and the çiftçi cultivar and the PI 173820, PI 426973, PI 469264, PI 572538, and PI 639185 genotypes were found with 0.40% and above trigonelline contents under irrigated conditions. In addition, eight genotypes were found with above-mean values, and the fenugreek cultivars remained below the general mean under dryland conditions. Five genotypes (PI 286532, PI 302449, PI 381062, PI 572538, and PI 617076) had similar trigonelline content under irrigated and dryland conditions. More than half of the fenugreek genotypes had higher trigonelline contents under dryland conditions compared to irrigated conditions. However, trigonelline contents of the çiftçi and gürarslan cultivars were higher under irrigated conditions. The advanced PI 426973 (originating from Pakistan) and PI 572538 (originating from Egypt) genotypes had high trigonelline content both under irrigated and dryland conditions. In addition, it was predicted that three genotypes (PI 426973, PI 194020, and PI 302448), which have high trigonelline content, can be grown in areas where irrigation is insufficient or water scarcity occurs in dryland conditions.

The trigonelline content of fenugreek is a substantial component to use in the pharmaceutical industry. For this context, PI 426973 and PI 572538 for both irrigated and dryland conditions, the çiftçi cultivar and the PI 469264 genotype for irrigated conditions, and the PI 426973, PI 302448, and PI 194020 genotypes for dryland conditions can be candidate varieties with high trigonelline contents to use in the medicinal and pharmaceutical industries.

3.3. Fixed Oil Content and Fatty Acid Profiles

Fixed oil contents and fatty acids of the seeds of 18 different fenugreek genotypes and two cultivars were detected, and the results are given in

Table 4. Fixed oil content of fenugreek genotypes and cultivars.

No	Genotype/Cultivar	Fixed Oil (%)		No	Genotype/Cultivar	Fixed Oil (%)
		Irrigated	Dryland			Irrigated	Dryland
1	Çiftçi	8.06 a–h	8.14 a–g	11	PI 381062	9.08 ab	6.92 c–ı
2	Gürarslan	6.58 e–ı	7.53 a–h	12	PI 426971	7.64 a–h	7.47 a–h
3	PI 173820	7.60 a–h	7.42 a–ı	13	PI 426973	7.74 a–h	6.08 ghı
4	PI 194020	8.25 a–f	8.16 a–g	14	PI 469264	8.83 a–d	7.11 b–ı
5	PI 215615	9.29 a	7.46 a–h	15	PI 568215	8.11 a–h	6.11 f–ı
6	PI 251640	7.85 a–h	7.56 a–h	16	PI 572538	7.60 a–h	6.87 d–ı
7	PI 286532	9.05 abc	7.55 a–h	17	PI 613633	7.86 a–h	5.27 ı
8	PI 296394	7.96 a–h	7.24 a–ı	18	PI 617076	8.94 a–d	5.98 hı
9	PI 302448	8.91 a–d	6.98 b–ı	19	PI 639185	8.73 a–d	7.03 b–ı
10	PI 302449	8.51 a–e	6.98 b–ı	20	PI 660995	8.00 a–h	8.42 a–e
Mean (cultivar–irrigated)		7.32
Mean (cultivar–dryland)		7.83
Mean (genotype–irrigated)		8.33
Mean (genotype–dryland)		7.03
General mean (irrigated)		8.23 a
General mean (dryland)		7.11 b
Fgenotype		0.88 *
Fapplication		21.97 *
Fgenotype×application		1.01 *

*: significant at 5% level. The values between the applications (irrigated and dryland conditions) marked with the same letters are not significant according to the least significant difference test at the 5% level. *: Significant at the 5% level.

. The fixed oil contents ranged from 6.58% to 9.29% under irrigated conditions and varied from 5.27% to 8.42% under dryland conditions. The highest fixed oil content under irrigated conditions was observed at 9.29% in the PI 215615 genotype originating from India, followed by the PI 381062 genotype (9.08%) originating from Iran and the PI 286532 genotype (9.05%) originating from India. The lowest fixed oil content was found in the gürarslan cultivar with 6.58%, and this cultivar was followed by the PI 173820 genotype originating from Türkiye and the PI 572538 genotype (7.60%) originating from Egypt under irrigated conditions. There was a difference of approximately 1.5-fold between the highest and the lowest values under irrigated conditions and more than 1.5-fold under dryland conditions in the fixed oil contents (Table 4). The PI 660995 genotype and the çiftçi cultivar had the highest fixed oil content under dryland conditions, and the PI 613633 genotype had the lowest fixed oil content among the fenugreek genotypes and cultivars under dryland conditions.

In total, eleven fatty acids were detected, and four major fatty acids (linoleic, linolenic, oleic, and stearic acids) were found, representing 37.60–89.28% and 64.60–94.60% of the total oil under irrigated and dryland conditions, respectively (Figure 1A,B). Linoleic acid (26.57–52.42%) was found as the first major component in the PI 572538 genotype, followed by 51.34% in the çiftçi cultivar and 50.35% in the PI 251640 genotype under irrigated conditions (

Table 5. Linoleic, linolenic, oleic, and stearic acid values of fenugreek genotypes.

No	Genotype/ Cultivar	Linoleic Acid (%)		Linolenic Acid (%)		Oleic Acid (%)		Stearic Acid (%)
		Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland
1	Çiftçi	51.34 a–d	45.71 a–e	16.77 a–g	15.17 c–ı	12.91 b–ı	8.04 e–m	7.44 g–o	12.91 c–j
2	Gürarslan	47.28 a–e	47.94 a–e	15.04 c–ı	11.69 h–n	6.35 h–m	6.83 g–m	7.39 g–o	6.35 k–o
3	PI 173820	48.13 a–e	54.12 ab	14.40 c–j	18.08 a–d	4.98 klm	7.19 f–m	11.44 c–l	4.98 l–o
4	PI 194020	41.69 b–e	52.59 abc	12.82 f–l	15.36 c–ı	8.65 e–m	5.50 j–m	5.71 k–o	17.65 bc
5	PI 215615	39.85 cde	56.82 a	6.84 op	18.26 a–d	6.77 g–m	4.77 lm	6.85 j–o	6.77 j–o
6	PI 251640	50.35 a–d	45.80 a–e	12.73 f–l	21.09 a	7.07 f–m	10.93 b–l	13.88 c–g	7.07 h–o
7	PI 286532	41.92 b–e	41.12 b–e	16.23 b–h	21.23 a	4.92 klm	12.47 b–j	17.10 bcd	5.92 k–o
8	PI 296394	48.43 a–e	45.39 a–e	15.17 c–ı	13.25 e–l	3.08 m	17.18 b	13.57 c–h	3.08 o
9	PI 302448	46.18 a–e	44.51 a–e	11.06 ı–o	20.31 ab	8.55 e–m	12.15 b–k	13.42 c–ı	8.55 f–o
10	PI 302449	44.50 a–e	44.56 a–e	9.92 j–o	18.66 abc	14.20 b–f	16.18 bc	4.85 mno	15.20 cde
11	PI 381062	44.14 a–e	38.91 def	13.84 d–k	15.88 b–h	5.35 j–m	4.46 lm	6.04 k–o	5.35 k–o
12	PI 426971	44.79 a–e	45.99 a–e	12.72 f–l	7.77 m–p	24.88 a	12.21 b–k	6.89 ı–o	24.88 a
13	PI 426973	36.31 ef	46.06 a–e	13.85 d–k	17.83 a–e	13.99 b–g	14.25 b–f	10.97 d–m	13.99 c–f
14	PI 469264	44.21 a–e	43.10 b–e	13.98 c–k	17.28 a–f	8.86 d–m	5.68 ı–m	5.17 l–o	6.86 j–o
15	PI 568215	46.76 a–e	47.66 a–e	17.13 a–g	13.10 f–l	5.83 ı–m	14.56 b–e	11.08 d–m	6.64 j–o
16	PI 572538	52.42 abc	43.60 b–e	12.51 g–l	13.95 c–k	5.93 ı–m	8.80 e–m	11.77 c–k	5.79 k–o
17	PI 613633	44.51 a–e	42.78 b–e	9.12 l–o	7.62 nop	7.26 f–m	13.63 b–h	14.70 c–f	4.16 no
18	PI 617076	26.57 f	48.72 a–e	3.46 p	7.74 nop	4.09 lm	16.14 bcd	3.48 o	3.66 o
19	PI 639185	48.93 a–e	46.16 a–e	12.45 g–m	18.01 a–d	8.97 c–m	6.74 g–m	10.27 e–n	4.78 mno
20	PI 660995	43.69 a–e	39.13 def	11.64 h–n	9.64 k–o	5.69 ı–m	17.32 b	22.28 ab	4.36 no
Cultivar mean		49.31	46.82	15.91	13.43	9.63	7.43	7.42	9.63
Genotype mean		44.08	45.94	12.22	15.28	8.28	11.12	10.53	8.31
General mean		44.60 ns	46.03 ns	12.58 b	15.10 a	8.42 b	10.75 a	10.22 a	8.45 b
Fgenotype		1.07 *		7.08 *		3.52 *		3.21 *
Fapplication		0.97 ns		23.25 *		8.38 *		5.96 *
Fgenotype×application		1.49 *		4.15 *		3.25 *		7.11 *

*: significant at 5% level; ns: not significant. The values between the applications (irrigated and dryland conditions) marked with the same letters are not significant according to the least significant difference test at the 5% level. *: Significant at the 5% level.

). This component changed between 38.91 and 56.82%, and the highest values were obtained from the PI 215615 and PI 173820 genotypes under dryland conditions. The lowest linoleic acid contents were found in genotype PI 381062, followed by the PI 660995 and PI 286532 genotypes. All genotypes and cultivars showed high quantities of linoleic acid. Table 5 shows that the second major fatty acid was found as linolenic acid under irrigated (3.46–17.13%) and dryland conditions (9.64–21.23%). The highest linolenic acid compositions were found in PI 568215 (Türkiye-originating genotype) and the çiftçi cultivar. The lowest values were obtained from PI 617076 (Bulgaria-originating genotype) and PI 215615 (India-originating genotype) under irrigated conditions (Table 5). All genotypes originating from India had the highest linolenic acid compositions under dryland conditions. The results showed that the fenugreek genotypes and cultivars are strongly recommendable for linoleic and linolenic acid production in this region, depending on the irrigated and dryland conditions.

The third major fatty acid was oleic acid. It changed between 3.08 and 24.88% under irrigated conditions and between 4.46 and 17.32% under dryland conditions among the fenugreek genotypes and cultivars (Table 5). The PI 426971 and PI 302449 genotypes had the highest values, and PI 296394 and PI 173820 had the lowest values under irrigated conditions. In dryland conditions, oleic acid was higher in the PI 660995 and PI 296394 genotypes compared to other fenugreek genotypes and cultivars. The lowest value was found in PI 381062, followed by PI 215615 and PI 194020. The fenugreek genotypes and cultivars had high n-3 (linolenic acid, ≥3.46%), n-6 (linoleic acid, ≥26.57%), and n-9 (oleic acid, ≥3.08%) contents under irrigated and dryland conditions. Stearic acid was found as the fourth major fatty acid among the fenugreek genotypes and cultivars under irrigated and dryland conditions (Table 5). Stearic acid content varied from 3.48% to 22.28% under irrigated conditions and from 3.08% to 24.88% under dryland conditions. Under irrigated conditions, the highest values were noted in the PI 660995 and PI 286532 genotypes, and the lowest values were obtained from the PI 617076 and PI 302449 genotypes. The highest and the lowest stearic values were found in the PI 426971 and PI 296394 genotypes under irrigated and dryland conditions, respectively.

Under irrigated conditions, the other fatty acid contents were between 0.88 and 8.85%, 0.25 and 8.35%, 0.29 and 13.33%, 0.35 and 2.52%, 0.12 and 11.27%, 0.40 and 3.62%, and 0.67 and 7.17% for palmitic, myristic, pentadecanoic, palmitoleic, margaric, behenic, and arachidic acids, respectively (

Table 6. Palmitic, myristic, pentadecanoic, and palmitoleic acid values of fenugreek genotypes.

No	Genotype/ Cultivar	Palmitic Acid (%)		Myristic Acid (%)		Pentadecanoic Acid (%)		Palmitoleic Acid (%)
		Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland
1	Çiftçi	2.84 e–k	5.99 a–d	1.19 e–h	1.20 e–h	0.85 bc	2.48 bc	1.33 b–l	2.18 b–f
2	Gürarslan	3.45 d–k	1.70 h–k	0.25 h	2.44 d–h	13.33 a	1.37 bc	0.35 l	1.26 b–l
3	PI 173820	4.28 d–h	4.74 d–g	0.81 fgh	1.62 d–h	0.29 c	2.04 bc	1.07 e–l	2.54 ab
4	PI 194020	7.78 abc	1.93 f–k	0.77 gh	2.49 d–h	0.60 bc	0.87 bc	0.67 g–l	0.87 g–l
5	PI 215615	3.22 d–k	3.17 d–k	1.99 d–h	5.03 c–h	2.40 bc	2.16 bc	2.38 a–d	0.49 ı–l
6	PI 251640	2.31 f–k	1.92 f–k	3.61 c–h	2.25 d–h	0.83 bc	1.99 bc	2.27 b–e	1.23 c–l
7	PI 286532	3.34 d–k	1.81 g–k	6.88 a–d	1.14 e–h	1.01 bc	1.99 bc	1.74 b–ı	0.45 jkl
8	PI 296394	4.03 d–h	2.29 f–k	5.82 b–g	2.08 d–h	1.09 bc	1.34 bc	0.98 e–l	1.17 d–l
9	PI 302448	3.97 d–ı	2.52 f–k	0.77 gh	1.72 d–h	1.38 bc	2.24 bc	1.82 b–h	1.68 b–k
10	PI 302449	8.85 a	0.74 jk	0.96 fgh	2.31 d–h	0.50 bc	1.11 bc	0.55 h–l	0.51 ı–l
11	PI 381062	3.06 d–k	2.60 e–k	6.44 a–e	11.02 ab	0.52 bc	1.55 bc	0.53 h–l	1.89 b–g
12	PI 426971	2.29 f–k	1.05 ıjk	0.70 gh	1.04 fgh	1.98 bc	1.40 bc	1.72 b–j	0.99 e–l
13	PI 426973	5.51 b–e	0.47 k	0.42 gh	0.57 gh	0.44 bc	2.22 bc	0.83 g–l	0.43 jkl
14	PI 469264	2.96 e–k	4.82 c–f	6.20 a–f	1.41 e–h	0.54 bc	0.77 bc	0.62 g–l	2.53 ab
15	PI 568215	2.80 e–k	2.01 f–k	1.83 d–h	5.02 c–h	0.59 bc	1.17 bc	1.41 b–l	1.51 b–l
16	PI 572538	5.54 b–e	3.08 d–k	2.35 d–h	1.44 e–h	1.10 bc	2.85 bc	0.68 g–l	3.65 a
17	PI 613633	4.34 d–h	3.98 d–ı	5.58 c–h	0.88 fgh	2.85 bc	1.31 bc	2.52 abc	1.61 b–l
18	PI 617076	0.88 jk	1.44 h–k	3.89 c–h	11.45 a	0.35 c	4.18 b	0.42 kl	1.02 e–l
19	PI 639185	8.36 ab	2.10 f–k	1.58 d–h	2.25 d–h	0.82 bc	1.65 bc	1.43 b–l	0.60 g–l
20	PI 660995	4.37 d–h	3.59 d–j	8.35 abc	1.03 fgh	0.58 bc	2.20 bc	0.91 f–l	1.63 b–l
Cultivar mean		3.14	3.85	0.72	1.82	7.09	1.92	0.84	1.72
Genotype mean		4.33	2.46	3.27	3.04	0.99	1.83	1.25	1.38
General mean		4.21 a	2.60 b	3.02 ns	2.92 ns	1.60 ns	1.84 ns	1.21 ns	1.41 ns
Fgenotype		2.35 *		2.64 *		2.31 *		2.26 *
Fapplication		23.85 *		0.03 ns		0.34 ns		1.97 *
Fgenotype×application		3.54 *		1.89 *		2.74 *		3.43 *

*: significant at 5% level; ns: not significant. The values between the applications (irrigated and dryland conditions) marked with the same letters are not significant according to the least significant difference test at the 5% level. ^ns: not significant.

and

Table 7. Margaric, behenic, and arachidic acid values of fenugreek genotypes.

No	Genotype/ Cultivar	Margaric Acid (%)		Behenic Acid (%)		Arachidic Acid (%)
		Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland
1	Çiftçi	0.67 de	1.35 de	-	-	2.29 d–j	0.52 g–j
2	Gürarslan	0.32 e	1.15 de	-	0.78 bcd	2.56 d–j	0.19 ıj
3	PI 173820	4.03 cde	1.55 cde	0.89 bcd		4.31 cde	1.08 f–j
4	PI 194020	11.27 a	–	-	-	4.46 bcd	0.10 j
5	PI 215615	3.81 cde	–	-	-	4.46 bcd	1.03 g–j
6	PI 251640	–	–	-	-	2.88 d–h	1.67 e–j
7	PI 286532	–	–	-	-	0.76 g–j	0.81 g–j
8	PI 296394	0.12 e	0.29 e	3.62 a	-	0.67 g–j	1.10 f–j
9	PI 302448	5.27 bcd	1.76 cde	-	1.76 a–d	2.90 d–h	0.79 g–j
10	PI 302449	1.80 cde	–	-	-	7.06 ab	0.31 hıj
11	PI 381062	5.33 bcd	–	-	-	3.69 c–f	0.54 g–j
12	PI 426971	–	0.59 de	-	-	2.63 d–j	0.79 g–j
13	PI 426973	2.67 cde	–	-	-	2.91 d–h	0.39 g–j
14	PI 469264	6.32 bc	–	2.07 abc	-	7.17 a	0.71 g–j
15	PI 568215	–	1.75 cde	0.40 cd	-	6.32 abc	0.42 g–j
16	PI 572538	1.13 de	2.29 cde	-	2.68 ab	3.03 d–g	0.43 g–j
17	PI 613633	1.5 cde	10.03 ab	0.79 bcd	-	2.62 d–j	0.89 g–j
18	PI 617076	–	0.50 de	0.71 cd	-	2.83 d–ı	0.65 g–j
19	PI 639185	–	4.82 cde	-	2.74 ab	1.60 f–j	1.39 f–j
20	PI 660995	–	–	-	-	1.30 f–j	1.72 e–j
Cultivar mean		0.50	1.25	0.00	0.78	2.42	0.35
Genotype mean		3.93	2.62	1.41	2.39	3.42	0.82
General mean		3.40 a	2.37 b	1.41 b	1.99 a	3.22 a	0.78 b
Fgenotype		2.04 *		1.35 *		1.73 *
Fapplication		2.77 ns		0.01 ns		75.79 *
Fgenotype×application		2.86 *		2.10 *		2.55 *

^ns: not significant; *: significant at 5% level. The values between the applications (irrigated and dryland conditions) marked with the same letters are not significant according to the least significant difference test at the 5% level.

). Under dryland conditions, considering the other components, palmitic acid varied between 0.47 and 5.99%, myristic acid varied between 0.57 and 11.45%, pentadecanoic acid varied between 0.77 and 4.18%, palmitoleic acid varied between 0.43 and 3.65%, margaric acid varied between 0.29 and 10.03%, behenic acid varied between 0.78 and 2.74%, and arachidic acid varied between 0.10 and 1.72% (Table 6 and Table 7).

Seeds of fenugreek genotypes and cultivars contained high levels of unsaturated fatty acids (USFAs) at 34.54–84.11% under irrigated and 61.14–81.93% under dryland conditions. Polyunsaturated fatty acids (PUFAs) comprised 30.03–68.11% and 50.40–75.08% of USFAs under irrigated and dryland conditions, respectively. Under irrigated conditions, the highest USFAs were characteristic of the genotype PI 426971 and the çiftçi cultivar. The lowest USFAs were found in the PI 617076 and PI 215615 genotypes. The highest and lowest PUFAs were detected in the çiftçi cultivar and the PI 617076 genotype, respectively. Under irrigated conditions, the highest USFA values were noted in the PI 173820 and PI 215615 genotypes, and the lowest USFAs were found in the PI 381062 and PI 613633 genotypes. The highest PUFAs occurred in PI 215615; the lowest value was found in the PI 613633 genotype (Figure 1C,D).

The means of cultivars, genotypes, and general means are shown in Figure 1 by using fatty acid compositions of fenugreek genotypes and cultivars. Under irrigated conditions, the mean major fatty acid compositions such as linoleic, linolenic, and oleic acids and minor fatty acid compositions such as pentadecanoic acid of cultivars were found to be higher than genotype means. Under dryland conditions, the mean linoleic, stearic, palmitic, and pentadecanoic acid levels of cultivars were found to be higher than genotype means (Figure 1).

3.4. Antioxidant Properties

The total antioxidant capacity values of fenugreek genotypes and cultivars were determined by the DPPH and FRAP methods. The findings of examined properties and statistical significance are compared in

Table 8. DPPH, FRAP, and total phenolic and flavonoid contents of fenugreek genotypes and cultivars.

No	Genotype/ Cultivar	DPPH (%)		FRAP (mg TE/100 g)		Total Phenolic (mg GAE/100 g)		Total Flavonoid (mg QE/100 g)
		Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland	Irrigated	Dryland
1	Çiftçi	48.88 abc	27.86 def	40.75 a–e	37.88 b–e	18.08 a–d	15.72 bcd	7.39 ab	8.69 ab
2	Gürarslan	43.18 a–f	31.94 b–f	45.28 a–e	53.76 ab	24.14 a–d	28.65 ab	8.27 ab	8.01 ab
3	PI 173820	47.45 a–e	28.56 c–f	41.67 a–e	39.93 a–e	19.88 a–d	20.01 a–d	8.89 ab	7.98 ab
4	PI 194020	50.94 ab	31.40 b–f	51.26 abc	49.29 a–d	25.87 a–d	23.01 a–d	8.88 ab	8.56 ab
5	PI 215615	41.30 a–f	40.53 a–f	56.92 a	33.71 cde	30.38 a	14.03 cd	8.70 ab	7.69 ab
6	PI 251640	50.46 ab	42.64 a–f	29.59 e	39.78 a–e	12.03 d	18.04 a–d	8.71 ab	8.31 ab
7	PI 286532	50.20 ab	35.67 b–f	43.86 a–e	35.05 cde	20.39 a–d	16.43 a–d	7.83 ab	8.11 ab
8	PI 296394	48.04 a–e	34.46 b–f	48.40 a–d	31.77 de	25.50 a–d	16.12 a–d	7.89 ab	7.79 ab
9	PI 302448	38.76 b–f	37.89 b–f	43.08 a–e	49.55 a–d	20.75 a–d	23.86 a–d	8.04 ab	9.10 a
10	PI 302449	42.36 a–f	35.51 b–f	33.96 cde	48.68 a–d	16.01 a–d	22.22 a–d	8.67 ab	8.51 ab
11	PI 381062	50.46 ab	33.42 b–f	51.36 abc	41.79 a–e	25.88 a–d	21.31 a–d	8.90 ab	7.57 ab
12	PI 426971	42.72 a–f	27.61 ef	45.70 a–e	38.20 b–e	24.18 a–d	15.73 bcd	8.21 ab	8.68 ab
13	PI 426973	48.65 a–d	35.83 b–f	47.06 a–e	42.66 a–e	23.38 a–d	19.43 a–d	8.21 ab	7.65 ab
14	PI 469264	33.58 b–f	39.45 b–f	45.96 a–e	34.95 cde	21.38 a–d	16.39 a–d	7.50 ab	6.99 b
15	PI 568215	60.59 a	25.59 f	49.02 a–d	45.16 a–e	26.74 abc	19.64 a–d	7.75 ab	8.33 ab
16	PI 572538	43.09 a–f	36.54 b–f	45.41 a–e	42.57 a–e	24.13 a–d	19.43 a–d	8.26 ab	7.56 ab
17	PI 613633	60.55 a	35.06 b–f	48.94 a–d	34.30 cde	26.81 abc	12.47 cd	7.82 ab	8.84 ab
18	PI 617076	43.54 a–f	34.76 b–f	51.76 abc	31.88 de	25.26 a–d	16.22 a–d	8.60 ab	7.80 ab
19	PI 639185	60.45 a	35.28 b–f	48.87 a–d	43.72 a–e	26.73 abc	20.90 a–d	7.71 ab	8.01 ab
20	PI 660995	47.60 a–e	34.74 b–f	48.71 a–d	33.99 cde	25.50 a–d	11.76 d	7.87 ab	8.06 ab
Cultivar mean		46.03	29.90	43.02	45.82	21.11	22.19	7.83	8.35
Genotype mean		47.82	34.72	46.2	39.83	23.38	18.17	8.25	8.09
General mean		47.64 a	34.24 b	45.88 a	40.43 b	23.15 a	18.57 b	8.21 ns	8.11 ns
Fgenotype		0.45 *		0.71 *		0.58 *		0.48 *
Fapplication		33.32 *		7.09 *		8.18 *		0.18 ns
Fgenotype×application		0.84 *		1.20 *		0.80 *		0.55 *

^ns: not significant; *: significant at 5% level. The values between the applications (irrigated and dryland conditions) marked with the same letters are not significant according to the least significant difference test at the 5% level.

. The DPPH values changed between 33.58 and 60.59% under irrigated and between 25.59 and 42.64% under dryland conditions.

Under irrigated conditions, PI 568215 originating from Türkiye had the highest DPPH value (60.59%), followed by PI 613633 (60.55%) originating from Australia and PI 639185 (60.45%) originating from Armenia. The lowest DPPH values were obtained from PI 469264 (originating from Egypt), PI 302449, and PI 215615 (originating from India). Under dryland conditions, the highest DPPH value was obtained in PI 251640 (originating from Ethiopia), PI 215615 (originating from India), and PI 469264 (originating from Egypt). PI 568215 (originating from Türkiye) had the lowest DPPH value, followed by the PI 426971 genotype and the çiftçi cultivar. The DPPH values obtained under irrigated conditions were found to be higher than under dryland conditions, except PI 469264 (originating from Egypt). This genotype had the lowest DPPH value under irrigated conditions, but it was found among the first three genotypes under dryland conditions (Table 8). In addition, the DPPH values of genotypes obtained from the USDA were found to be high from local cultivars under both irrigated and dryland conditions.

FRAP values varied between 29.59 and 56.92 mg TE/100 g under irrigated conditions and between 31.77 and 53.76 mg TE/100 g under dryland conditions (Table 8). The highest FRAP values among the fenugreek genotypes and cultivars under irrigated conditions were PI 215615 (56.92 mg TE/100 g) originating from India, PI 617076 (51.76 mg TE/100 g) originating from Bulgaria, and PI 381062 (51.36 mg TE/100 g) originating from Iran. Under dryland conditions, the highest FRAP value was determined in the gürarslan cultivar (53.76 mg TE/100 g), followed by PI 302448 (49.55 mg TE/100 g) originating from India and PI 194020 (49.29 mg TE/100 g) originating from Ethiopia. The lowest FRAP values were found in the PI 251640 and PI 302449 genotypes under irrigated conditions, and the PI 296394 and PI 617076 genotypes had the lowest FRAP values under dryland conditions.

3.5. Total Phenolic and Flavonoid Contents

The total phenolic content ranged from 12.03 to 30.38 mg GAE/100 g, representing an approximate two-and-a-half-fold variation among the fenugreek genotypes and cultivars under irrigated conditions (Table 8). PI 215615, PI 613633, PI 568215, and PI 639185 had the greatest phenolic contents (30.38, 26.81, 26.74, and 26.73 mg GAE/100 g, respectively), while the lowest total phenolic contents were found in PI 251640, PI 302449, the çiftçi cultivar, and PI 173820 (12.03, 16.01, 18.08, and 19.88 mg GAE/100 g, respectively) under irrigated conditions.

Under dryland conditions, the total phenolic contents changed between 11.76 and 28.65 mg GAE/100 g (Table 8). The highest total phenolic content was determined in the gürarslan cultivar with the PI 302448, PI 194020, and PI 302449 genotypes. The lowest total phenolic contents were determined in genotypes PI 660995 with 11.76 mg GAE/100 g, PI 613633 with 12.47 mg GAE/100 g, and PI 215615 with 14.03 mg GAE/100 g. While genotypes PI 215615 and PI 613633 had the highest total phenolic content under irrigated conditions, these genotypes had the lowest values under dryland conditions. Total flavonoid content values of fenugreek genotypes and cultivars were found between 7.39 and 8.90 mg QE/100 g under irrigated conditions and between 6.99 and 9.10 mg QE/100 g under dryland conditions (Table 8). The highest total flavonoid values were determined in PI 381062, PI 173820, and PI 194020 genotypes with 8.90, 8.89, and 8.88 mg QE/100 g, respectively, under irrigated conditions, while the highest values were determined in PI 302448 with 9.10 mg QE/100 g, PI 613633 with 8.84 mg QE/100 g, and the çiftçi cultivar with 8.69 mg QE/100 g under dryland conditions. The çiftçi cultivar and the PI 469264 genotype had the lowest total flavonoid contents under irrigated conditions, and the PI 572538 and PI 381062 genotypes had the lowest total flavonoid contents under dryland conditions. The highest total flavonoid contents were obtained from 11 genotypes under irrigated conditions compared to dryland conditions.

3.6. Biplot Analysis

A biplot analysis was conducted to determine the relationship between the fenugreek genotypes and cultivars based on major fatty acid compositions (linoleic, linolenic, oleic, and stearic acids) under irrigated and dryland conditions (Figure 2A,B). In total, the biplot analysis accounted for 53.33% of total variations, and biplot-1 accounted for 28.68% (Figure 2A). Biplot-2 explained 24.65% of the total variation. Generally, biplot-1 and biplot-2 revealed close values. The results obtained from the biplot analysis revealed the presence of well-discriminated and defined groups. The first group was represented by linolenic (irrigated–dryland) and linoleic acids (irrigated). The second group consisted of oleic (dryland) and stearic acids (irrigated) with PI 296394, PI 660995, and PI 613633. Stearic (dryland) and oleic acids (irrigated) made up the third group, and linolenic acid (dryland) was clearly differentiated from other groups. Figure 2B showed that 55.14% of total variations were found, and biplot-1 comprised 32.04% of the total variations. Biplot-2 had 23.10% of total variations. The first group was represented by TFC-irrigated with two genotypes. The second group consisted of TFC-dryland, TPC-dryland, and FRAP-dryland with three genotypes and two cultivars. FRAP-, TPC-, and DPPH-irrigated took place in the third group with five genotypes, and DPPH-dryland was clearly differentiated from other groups and included eight genotypes.

3.7. Cluster Analysis Results

Cluster analysis was conducted to determine the genetic differences among the fenugreek genotypes and cultivars under irrigated and dryland conditions by using the Ward method in hierarchical clustering analysis (Figure 3). So, the determination of the genetic differences by yield and quality properties for sustainable agriculture under dryland or water-scarcity areas is an important crop-breeding method. The similarity index among the clusters, which indicates 0–100% from left to right, is represented as a blue line at the bottom in the cluster analysis results (Figure 3). The hierarchical cluster analysis formed four distinct clusters based on the 36 total examined properties of fenugreek genotypes grown under irrigated (18 properties) and dryland (18 properties) conditions at a 79.03% similarity level. The cluster analysis clustered the fenugreek into two main groups, A and B. Group A contained six genotypes, and it was divided into two sub-groups (A1 and A2). This main group was found to be different from group B depending on the behenic acid content under dryland conditions. The A1 sub-group had the PI 215615 and PI 617076, genotypes which originated from India and Bulgaria. The A2 sub-group contained four fenugreek genotypes, and the genotypes’ origins were from different countries (one India, two Pakistan, and one Ethiopia). Group B included 12 fenugreek genotypes and two cultivars. It was divided into two main sub-groups, B1 and B2. The B1 sub-group contained five genotypes from different origins and two cultivars. The B2 sub-group contained the rest of the fenugreek genotypes, and most of the genotypes (about 39%) were in this sub-group (Figure 3). In addition, the distances found between the fenugreek genotypes depended on the fatty acids, antioxidant activity, and total phenolic and flavonoid contents. The maximum distance was found between the çiftçi cultivar and the PI 194020 genotype, and the minimum distance was found between the PI 286532 and PI 660995 genotypes (Supplementary Table S1).

4. Discussion

4.1. Plant Height, Branch Number, and Seed Yield

The plants had the highest plant height with increasing vegetative parts and decreasing row spacing. This situation can be explained by the increasing light competition [33]. In addition, it has been stated that the height of plants decreases with the restriction of irrigation [34,35]. When we evaluated the two experimental years’ results, our findings were in line with the findings of previous studies. The obtained results in this study showed that continuous and regular irrigation regimes have a positive effect on the number of branches in fenugreek genotypes and cultivars compared to dryland conditions.

These findings were partly similar to [36], who reported that branch numbers changed between 2.3 and 7.5 in 245 fenugreek genotypes. Similarly, the branch number of different fenugreek genotypes was found to be 2.18–7.98 [37], 2.40–4.90 [38], and 1.00–4.33 [39].

The yield property of the fenugreek is the most important besides morphological properties such as plant height and branch number, which must be taken into account. Seed yield showed differences in the vegetation periods (2019 and 2020) among the fenugreek genotypes and cultivars grown under irrigated and dryland conditions. One of the main reasons for the difference in seed yield between years and genotypes is the difference in precipitation amounts during the vegetation period (April–August). It is seen that the highest seed yield values are obtained by growing some genotypes in dry conditions depending on the total amount of precipitation.

It was reported that morphological properties such as plant height and branch number can be closely related to seed yield in fenugreek [40]. It has been reported that the seed yield is higher in fenugreek genotypes with higher plant height, maturation time, and biological yield [4]. In addition, it was reported that seed yields vary depending on years, sowing date, harvest date, climatic conditions, and irrigation [41]. So, it was observed that the differences in seed yields under irrigated conditions were directly related to plant heights, and the genotypes with plant heights below 50 cm had a seed yield of less than 50 kg/da.

4.2. Total Alkaloid and Trigonelline Contents

Most of the fenugreek cultivars had an alkaloid content higher than 2%, and the values were higher in irrigated conditions compared to dryland conditions. Six genotypes under irrigated conditions and seven genotypes under dryland conditions were found to be lower than 2%. It was reported that the alkaloid content of plants can be used for antinociception applications [42]. So, the PI 286532 (originating from India) and PI 639185 (originating from Armenia) genotypes came to prominence in terms of total alkaloid contents under both irrigated and dryland conditions, and these genotypes can be selected for antinociception action.

It was reported that alkaloid content was 2.42% in raw fenugreek seeds, 3.18% in boiled fenugreek seeds, and 1.16% in germinated fenugreek seeds [43]. It was noted that the alkaloid contents of fenugreek seed were 2.12% in decoction and 1.71% in maceration [25]. In addition, Ref. [44] found alkaloid content to be 1.8%. The obtained alkaloid content results from the present study are similar to previous studies.

The lower-trigonelline-content genotypes do not lack trigonelline content. This is because trigonelline yield depends on the seed yield and trigonelline concentration. In fact, water deficiency and drought stress affect the seed yield of fenugreek negatively. These conditions affect the trigonelline concentration of fenugreek seeds. It is worth mentioning that genotypes with high trigonelline content cannot provide economic benefits under stress conditions depending on the productive criteria [45,46]. Also, high concentrations of fenugreek trigonelline contents occur to prevent the massive generation of ROS and damage by photoinhibition under dryland conditions [45,47].

Overall, the dryland conditions increased the trigonelline content of the fenugreek seeds. This can be explained by the availability of N due to the slower release of N, depending on the water scarcity of the soil under dryland conditions, and through additional N availability to the soil by the N fixation of fenugreek [48]. Trigonelline, an alkaloid component, is produced through the methylation of nicotinic acid. It has been reported that N is an amino acid and metabolite component, and it has a positive effect on enhancing alkaloids [49].

Our trigonelline content (0.23–0.48%) results are lower than the findings of [50] and [51], but higher than the findings reported by [26]. The obtained trigonelline content from this study differed from the previous study. This can be explained by the growing conditions, soil properties, ecological conditions, and genotype differences.

4.3. Fixed Oil Content and Fatty Acid Profiles

The PI 660995 genotype and the çiftçi cultivar had the highest fixed oil content under dryland conditions, and the PI 613633 genotype had the lowest fixed oil content among the fenugreek genotypes and cultivars under dryland conditions.

A previous study reported that the fixed oil content of fenugreek is highly effective in the inhibition of coronary heart diseases, inflammation, and cancer [18]. So, the PI 215615, PI 381062, and PI 286532 genotypes (over 9%) under irrigated conditions, PI 660995 and PI 194020 genotypes with the çiftçi cultivar (over 8%) under dryland conditions, and PI 215615 and PI 286532 genotypes (over 8%) for the mean of the irrigated and dryland conditions can be selected for the inhibition of coronary heart diseases, inflammation, and cancer.

Our fixed oil content results were found to be higher under irrigated conditions (6.58–9.29%) and under dryland conditions (5.27–8.42%) than those of [39], who found that the fixed oil content of fenugreek ranged from 2.26 to 4.93% under different sowing times. Similarly, it was found that the fixed oil content ranged from 4.75 to 5.54% [51] and from 5.18 to 9.16% [52]. By contrast, it was noted that the fixed oil content of different fenugreek genotypes ranged from 2.17 to 15.52% [37] and that fenugreek fixed oil content ranged from 4.32% to 11.62% in fenugreek seeds [7]. The results of the current study were similar to [37] and [51]. However, differences in fenugreek fixed oil content between this study and [39] and [52] could be due to different environmental conditions, genetic variability, and growth conditions. This is because it has been reported that water stress changes seed composition and related qualities and decreases the fixed oil content of plants [53,54].

Linoleic acid is known as the primary dietary omega-6 fatty acid. Omega-6 fatty acids act as structural components of membranes, influencing membrane function, and as precursors of eicosanoids, which modulate renal and pulmonary function, vascular tone, and inflammatory responses [55]. Genotypes with linoleic acid content of 22% or more are in the drying oil category. So, all these fenugreek genotypes and cultivars can be used in paints, varnishes, lacquers, and ink for printers [8]. Previous studies reported that the linoleic acid content of fenugreek varied between 31.30 and 46.80% [56] and between 37.7 and 38.4% [57]. The current study results (38.91–56.82%) were found to be partly similar to previous studies. The differences can be explained by the fenugreek growth area, growing conditions, and analysis methods [7,58].

Previous studies reported that fatty acids such as linoleic and linolenic acids have health benefits that can be useful in preventing diabetes, inflammation, and cardiovascular disease [59]. So, all genotypes and cultivars except the PI 617076 and PI 660995 genotypes can be selected and cultivated for the benefit of preventing many different types of diseases under irrigated and dryland conditions.

The linolenic acid content (3.46–21.23%) obtained from the current study under different growing conditions was found to be lower than [60] and [51], who reported linolenic acid contents between 26.47 and 28.04% and between 26.77 and 29.21%, respectively. The variability in linolenic acid compositions between these findings and previous studies can be explained by variations in temperature and atmosphere during the vegetation period, extraction conditions and methods, different genotypes, ecological conditions, and cultivation techniques [61]. Previous studies reported that oleic acid can be used as an excipient in pharmaceuticals and as an emulsifying or solubilizing agent in aerosol products. In addition, it can hinder the progression of adrenoleukodystrophy, which affects the brain and adrenal glands, and it may help boost memory. Oleic acid may also reduce blood pressure [62]. As seen in Table 4, PI 302449, PI 426971, and PI 426973 are the best genotypes with over 10% oleic acid contents under both irrigated and dryland conditions. So, these genotypes are suitable for the production of oleic acid for use in human health and disease. The oleic acid contents of the fenugreek genotypes and cultivars were partly compatible with [37] and [51].

The range of stearic acid content varied from 3.48% to 22.28% under irrigated conditions, and it varied from 3.08% to 24.88% under dryland conditions and was higher than the mean stearic acid content (4.50%) found by [8].

Similarly, Ref. [6] noted that stearic acid was found to be 3.85%. In addition, Refs. [51,57] reported that stearic acid changed between 3.66 and 4.53% under different growing conditions. Differences in stearic acid content between this study and other reports could be due to genotype differences, growing and environmental conditions, planting times, and fertilization.

The results show that most of the genotypes with MUFAs and PUFAs in this study can be used for the alteration of the plasma lipoprotein profile and for reducing the risk of cardiovascular disease [8]. In addition, PI 173820, PI 251640, PI 568215, and PI 639185 genotypes and the çiftçi cultivar had the highest PUFA values of over 60% in both irrigated and dryland conditions. So, these genotypes and the çiftçi cultivar can be selected and cultivated for use in human health such as cancer prevention, cardiovascular diseases, inflammation, diabetes, autoimmune diseases, renal problems, and rheumatoid arthritis, and also in Crohn’s disease and hypertension [63,64].

4.4. Antioxidant Properties

Antioxidants of plants decrease the risks of chronic diseases such as cancer and heart disease. Primary sources of antioxidants are known as whole fruits, grains, and vegetables [65].

The obtained DPPH values in this study were found to be lower than the antioxidant value (80.53%) reported by [66]. However, the obtained DPPH values were partly similar to [67] and [68], who reported 43.6–67.30% and 51.60%, respectively. It was reported that extraction methods or processes affect antioxidant values in fenugreek, and different values were obtained [69]. In addition, it has been noted that quantitative and qualitative changes in phenolic compounds during germination periods affect antioxidant properties [70]. The different results of DPPH values in previous studies can be explained by the extraction methods and processes besides genotype differences, cultivation applications, and ecological conditions.

The FRAP values were found to be similar to [67] (31.85–47.49 mg TE/100 g) and [25] (56.37 mg AAE/100 g, 56.90 mg AAE/100 g), but the values were found to be lower than [71] (58.31 mg TE/g). The differences can be linked to genotype, environment, and seed extraction methods and the used solutions.

4.5. Total Phenolic and Flavonoid Contents

In recent years, natural diets rich in phenolic and flavonoids with antioxidant activity have received increased interest in nutrition and food science [72]. Phenolic compounds, which have redox properties responsible for antioxidant activity, are substantial plant ingredients [73]. When we evaluated the two different condition results, the PI 215615 and PI 613633 genotypes had the highest total phenolic contents under irrigated conditions, and the gürarslan cultivar with the PI 302448 genotype had the highest total phenolic contents under dryland conditions. So, these genotypes are suitable for the production of preservatives in the nutrition and food industries.

Previous studies have reported a range of values of phenolic contents for fenugreek genotypes, from 1.35 mg GAE/g DW to 25.90 mg GAE/g DW. The authors of ref. [74] reported values ranging from 1.35 to 6.85 mg GAE/g DW. The authors of ref. [67] reported that the total phenolic content ranged from 15.45 to 25.90 mg GAE/100 g. The authors of ref. [75] reported that the total phenolic contents of four fenugreek varieties from Algeria ranged from 1.40 mg to 2.08 mg GAE/g.

In our study, total phenolic contents found in the fenugreek extracts were much higher than in all of these previous studies, except [67]. The observed differences could, in part, be related to the use of different genotypes, and the high number of evaluated genotypes and standards for calculation. In addition, it has been reported that the differences in phenolic content may be affected by environmental factors such as the ripening period of the plant, climate, location, temperature, fertilization, diseases, used parts of the plant, and exposure to pests [76]. It has also been reported that precipitation affects the phenolic content [77].

Flavonoids are one the most significant components used in nutraceutical, pharmaceutical, medical, and cosmetic applications [30]. So, identifying flavonoid-rich genotypes is important among the fenugreek genotypes and cultivars under irrigated and dryland conditions. The obtained flavonoid content results from the fenugreek genotypes and cultivars in this study were compared with previous studies; they were found to be higher than [75], lower than [18] and [71], and partly similar to [38]. In the optimization study performed with different methods such as extraction temperature, time, and mixing speed, as a result of mechanical mixing in fenugreek, it was stated that total phenolic, flavonoid, and antioxidant properties showed variability, and these properties were significantly affected by the optimization study applications [78]. Flavonoids are compounds that are secondary metabolites but play an important role in the biological activities of plants. They may be responsible for the color of flowers and fruits and attractiveness to pollinators. They also participate in plant–microorganism symbiosis. These relationships can be used to naturally control weeds and insect pests to increase crop yields and reduce stress and disease [79]. Thus, the PI 381062, PI 302448, and PI 613633 genotypes with the highest total flavonoid contents can be selected for agricultural production.

As a result of the spectrophotometric analysis, DPPH, FRAP, and the total phenolic and total flavonoid contents of genotypes (obtained from the USDA) were found to be higher than cultivars under irrigated conditions and lower than other traits except for the DPPH value under dryland conditions.

4.6. Cluster Analysis

The results of the cluster analysis showed that Pakistan-origin genotypes were placed in the same main (A) and sub-main groups (A2), and Türkiye- and Egypt-origin genotypes were found in the same main and sub-main groups (B and B2) together with cultivars. However, the other same-origin genotypes from Iran and India showed different properties and were placed in different groups. Previous studies reported that same-origin genotypes can be found in different groups regardless of geographical situation [20,21,78,80].

5. Conclusions

According to the presented results, significant differences were found among the fenugreek genotypes from different origins based on the chemical characteristics of the seeds, such as fixed oil and its acids, trigonelline, total alkaloids, antioxidants, and the phenolic effectiveness of ethanol extracts under irrigated and dryland conditions. Although different fenugreek genotypes were found to have high values in different properties under irrigated and dryland conditions, this study revealed that fenugreek can be grown without irrigation for its seed yield, trigonelline, total alkaloid, fixed oil, fatty acids, DPPH, FRAP, and total phenolic and flavonoid contents. Generally, the PI 617076, PI 568215, and PI 660995 genotypes had the highest seed yield values, and these genotypes can be selected for cultivation under irrigated and dryland conditions.

The PI 426971 and PI 572538 genotypes can be selected to obtain the highest trigonelline content, and the PI 215615 and PI 660995 genotypes can be recommended for the highest fixed oil content. The highest DPPH, FRAP, and total phenolic and flavonoid contents were found under irrigated conditions compared to dryland conditions. Also, the PI 568215 and PI 613633 genotypes can be selected for their high DPPH and total phenolic content when grown under irrigated conditions. The biplot and cluster analysis revealed genetic differences, and the results of the cluster analysis were divided into two main groups. Most of the genotypes and cultivars were placed in the same group.

So, the current study results reveal beneficial information for fenugreek breeders, producers, and researchers looking to increase the contents of trigonelline, alkaloid, fixed oil, and fatty acids. In addition, these results will serve as guidance for breeders who are aiming to develop drought-resistant fenugreek cultivars.