Next Article in Journal
The Application of Fulvic Acid Can Enhance the Performance of Rice Seedlings Under Low-Nitrogen Stress
Previous Article in Journal
Integral Assessment of Species of the Genus Allium L. (Amaryllidaceae) in the Western Part of the Kyrgyz Alatau
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Plants
Volume 14
Issue 18
10.3390/plants14182891
plants-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Effects of Plant Density and Fertilization on Agronomic Traits and Yield of Flax (Linum usitatissimum L.)

by
Panteleimon Stavropoulos
,
Antonios Mavroeidis
,
Antigolena Folina
,
Ioannis Roussis
,
Stavroula Kallergi
,
Stella Karydogianni
,
George Papadopoulos
and
Ioanna Kakabouki
*
Laboratory of Agronomy, Department of Crop Science, Agricultural University of Athens, 11855 Athens, Greece
*
Author to whom correspondence should be addressed.
Plants 2025, 14(18), 2891; https://doi.org/10.3390/plants14182891
Submission received: 15 August 2025 / Revised: 15 September 2025 / Accepted: 15 September 2025 / Published: 18 September 2025
(This article belongs to the Section Crop Physiology and Crop Production)
Browse Figures
Versions Notes

Abstract

Flax (Linum usitatissimum L.) is a retrovative crop with highly nutritious seeds. The study aimed to assess the effect of plant density and type of fertilizer on crop growth and productivity. A three-year experiment was conducted at the Agricultural University of Athens, focusing on two densities (D1 and D2) and four fertilizers (urea with inhibitors (I), organic (O), urea (U) and control (C)). Measurements included plant height, dry weight, number of capsules, number of seeds per capsule, Thousand Seeds Weight (TSW), yield, Harvest Index (HI), seed oil content and oil yield. Fertilization increased plant height (14.6–15.2%), dry weight (34.1%) and number of capsules (24.9%). D2 improved biomass production by 52.6%, while D1 increased the number of capsules by 16.4%. TSW increased by 6.7 and 23.9% at D2 and fertilized treatments, respectively. Yield, HI and oil yield were affected by the interaction of density and fertilization, while seed oil content was affected only by fertilization. D2I increased yield by 67.9% compared to D2C, while oil yield increased over twofold. Overall, flax represents a promising alternative crop against climate change in the Mediterranean Basin.

1. Introduction

Climate crisis and its immediate effect on agriculture [1,2,3,4] have highlighted the potential of alternative crops [5,6] as an adaptation strategy to the rising temperatures, drought and other extreme weather phenomena [7,8,9]. Flax (Linum usitatissimum L.) has been described as a retrovative crop for the Mediterranean [6,10]. It is a member of the Linaceae family, while the Latin word “usitatissimum” describes the many different uses it has [11,12]. The main uses of the crop are high quality fiber production, known as linen [13,14,15] and seed production, either for consumption as whole seeds [16,17,18,19] or for the extraction of highly nutritious oil [20,21,22,23,24]. The interest in flax seeds consumption is rising [25,26]. The main reason is their high nutritional value. They are rich in alpha-linolenic acid (ALA) [27,28], while the seed protein content is about 10% [29]. Linseed is mainly cultivated in Russia, Kazakstan, Canada, China and the USA [30,31]. In recent years, the interest in flax cultivation in the Mediterranean Region has been rising [32]. Many studies have focused on the sowing and harvest time, irrigation, tillage and fertilization rates [32,33,34,35].
Studies suggest that fertilization and plant density are two major factors influencing flax performance [36]. Sowing densities vary depending on whether flax is cultivated for fiber production (110–140 kg ha−1) or seed and oil production (50–60 kg ha−1) [37]. Higher densities can lead to the improvement of straw, fiber and seed yield [38,39,40], while lower densities result in the growth of more branches [41], a negative trait for fiber production [38]. Similarly, the use of nitrogen (N) fertilizers can improve crops’ growth and yield [42,43,44]; however, the literature suggests a wide range of N fertilization rates (20–150 kg N ha−1) as optimal [45]. Urea is the most common fertilizer [46,47,48], yet the use of inhibited fertilizers has been proven as a viable, less environmental harming and a more efficient alternative to urea [46,47,48,49,50,51,52,53,54,55,56]. This type of fertilizer delays the release of urea in the ground. As a result, losses are lower while the efficiency of the fertilizer is increased [57]. The urease inhibitor thiophosphorictriamide (NBPT) and the nitrification inhibitor dicyandiamide (DCD) are the most common inhibitors. They focus on the reduction in the formation NH4+ and NO3− [58]. Additionally, the use of organic fertilization also has a positive impact on flax crops. Manure [59,60,61,62,63], Plant Growth-Promoting Microorganisms (PGPM) [64,65,66] and other soil amendments can increase seed yield. Among these amendments tomato pomace, a sub-product of the processing of industrial tomatoes [67], has been suggested to improve the agronomic traits and the yield of several crops when combined with other organic fertilizers (manure, compost) [68,69].
Notably, and despite the rising popularity that flax is gaining in some Mediterranean countries, studies conducted in the region have not thoroughly assessed the effect of plant density, fertilization rates, fertilization type and their interaction remain rather limited in the region. According to Kakabouki et al. [35] flax fertilization requirements are estimated at 30–60 kg N ha−1, yet in their study they did not evaluate the efficiency of fertilization in different plant densities, nor did they study the effects of different fertilizer types on the crop. Moreover, research on the application of organic fertilizers and soil amendments in flax in the Mediterranean, and their interaction with different plant densities is rather limited. The aim of the present study is to assess the effect of two different plant densities and three different fertilization types in flax, under Mediterranean conditions.

2. Results

2.1. Agronomic Characteristics

All data presented in the tables (Table 1, Table 2, Table 3 and Table 4) and in Figure 1 correspond to mean values calculated across the three-year experimental period (2023–2025). Overall, based on the results of the present study, both fertilization and plant density significantly affected the performance of flax. In particular, the application of I reported the highest yields, number of capsules, and TSW. On the contrary, plant density affected only the number of capsules and the TSW, particularly in D2 where the best results were reported. According to the statistical analysis, fertilization significantly affected the agronomic characteristics of the crop, as presented in Table 1. Plant height was statistically significantly higher in fertilized treatments than the control (unfertilized). The use of urea had a higher impact on plant height, increasing it by 15.2%, compared to the control, while this increase was 14.6% by using the urea +UI +NI. A smaller increase in the same characteristic was also observed by using organic fertilizer (10.5%). The dry weight was also affected by the type of fertilizer. Statistically significant differences were observed at both densities, for the dry weight, where the use of fertilizer increased it by 34.6, 22.3 and 45.6% for I, O and U, respectively, compared to the control (Table 1). The number of capsules was statistically significantly higher (in a mean value of 22.6%) in all of the fertilized plots compared to the control. The number of capsules increased by 27.9, 16.9 and 23.1%, for I, O and U, respectively (Table 1).
Following fertilization, the dry weight and the number of capsules were also affected by density, as shown in Table 2. Dry biomass was higher in D2. Lower density reported a 65.3% increase in the plant’s dry weight. The number of capsules was significantly affected by density (Table 2). The decrease in plants’ density caused a 16.8% increase in the number of capsules per plant.

2.2. Yield and Yield Components

The number of seeds per capsule was not significantly affected by any of the factors. Both year, density and fertilization did not statistically significantly influence the number of seeds per capsule (Table 3). The TSW was significantly affected by both density and fertilization. As presented in Table 2, the control reported a 0.2% higher TSW in D2. Fertilized treatments had no significant differences between densities. In D1, C reported the lowest TSW. An increase of 20.2% reported in the use of U, compared to C, while this increase was 28.7 and 40.9%, for O and I, respectively. In D2, the highest TSW was reported in I, with an increase of 27.3%, followed by O (19.4%) and U (8.9%), compared to C. No significant differences were observed in O and I in D2, while in D1, O did not report any statistical differences from both U and I (Table 3).
Crop yield was influenced by the interaction of density and fertilization (PD×F < 0.001). As presented in Figure 1, higher yields were reported at higher densities. The use of fertilizers also increased crop yield. The highest values were reported at the D1I and D2I treatments. No significant differences were observed between these treatments for all the years. The use of urea + UI + NI increased yield by 33.3%, followed by urea with an increase of 8.33%. Organic fertilizer reported the lowest yields for both D1 and D2. Yields in D1 were higher than those in D2. The decrease in plant density caused a 11.3% decrease in the crop’s yield. The combination of high density and urea with inhibitors increased yield by 12.22%, while this increase was 65.5% at the lower density.
Harvest Index (HI) was significantly statistically affected by the interaction of density and fertilization. Urea + UI + NI at D2 reported the highest values of HI (Figure 1). The combination of low density and fertilization with inhibitors almost doubled HI. The addition of fertilizer increased HI by 45 and 26% for organic fertilizer and urea, respectively. Lower values were reported at the control in both D1 and D2, with no significant differences between these two treatments.
The seed oil content was affected by fertilization (Table 4). The use of fertilizers increased oil content by 42.8%, compared to the unfertilized treatment. No statistically significant differences were observed between the fertilized treatments; although, seed oil content was 43.5, 40.2 and 44.6% higher than the control, at urea with inhibitors, organic and urea, respectively. Oil yield was affected by the interaction of plants’ density and fertilization (Figure 1). The highest oil yield was reported at D1I and D2I, where it was doubled, compared to the control. Lower density increased oil yield by 10.2%, while the use of fertilizers increased it by 58.2%. Inorganic fertilizers increased oil yield by 39.21% compared to organic fertilizer, where O increased this characteristic by 25.5%, compared to C.

3. Discussion

The analysis of the results shows that the factor year did not have a statistically significant effect on the results of the study. This is a reasonable result, as there were no major differences in both temperature and rainfall between the three years. On the contrary, both plant density and fertilization had a statistically significant effect on the results. Other studies show that both density and fertilization can indeed influence the growth and yield of flax [35].
Plant height was statistically significantly influenced by fertilization. The use of urea increased this trait, because it is an easily assimilated form of nitrogen by the plant and it has been proposed that it promotes plant growth in flax [35]. On the contrary, fertilizers containing inhibitors resulted in lower plant height due to the gradual release of urea. The use of chemical fertilizers, urea and urea with inhibitors, increases plant height compared to the control [70]. Organic fertilizer also increased height, although to a lesser extent, probably due to the slow release of nutrients into the soil. According to Kakabouki et al. (2020) [71], the use of tomato pomace, either as such or in a mixture with other organic fertilizers, increased height in maize crops. Whereas in a study by Abdulazeez et al. (2025) [72], the use of organic fertilizer increased height in flax plants. As expected, the use of any fertilizer increased plant height as the concentration of nutrients in the soil increased.
The dry weight of the plant was statistically significantly affected by both factors in the experiment. Lower plant density reduced competition among plants [38], while more nutrients are provided to the plant. As a result, the plant can absorb a greater amount of nutrients which it utilizes to produce biomass [35]. In a study by Arslanoglu et al. (2022) [38] on the effect of spacing on flax cultivation, they found similar results, with density reduction increasing biomass yield. The dry weight of the plant was also affected by fertilization. The use of fertilizer increased this characteristic [73]. Increased plant biomass resulting from nitrogen (N) fertilization has been consistently reported in the literature. For instance, Soethe et al. [74] observed a positive correlation between N fertilization and flax biomass. Kakabuki et al. [35] proposed that this could be attributed to increased photosynthetic rate due to the abundance of N or the extension of the vegetative phase promoted by fertilization.
The number of capsules was statistically significantly affected by both factors of the experiment. Plant density had a statistically significant effect on the results, with low density increasing the number of capsules, probably due to greater nutrient availability to the plant per unit area [35]. Other studies suggest that the application of sparse seeding to flax crops can improve its growth [36]. Similarly, the use of fertilizer increased the number of capsules per plant. The use of inorganic fertilizers has been known to improve flax agronomic traits [75], while the use of organic fertilizers containing tomato pomace has mainly been studied in industrial tomatoes [69].
The number of seeds per capsule was not statistically significantly affected by either density or fertilization type. According to a study by Rajanna et al. (2020) [76] the number of seeds per capsule is a genetic factor, so it is reasonable that it was not affected by the factors of the experiment.
TSW was statistically significantly affected by the factors of the experiment. More specifically, the low density gave a higher TSW, probably due to the higher concentration of plant nutrients and less competition, compared to the highest density [38]. Similarly, fertilizer use helped this trait. The highest values were reported at the urea with inhibitors. This result is consistent with expectations, as there is a slow release of nitrogen into the soil, resulting in the plant being provided with nitrogen for a longer period of time [35]. Similarly, organic fertilizer increased this trait. Organic fertilizers improve some soil properties, which in turn led to better nutrient uptake by the plant [71]. Studies show that the use of organic fertilizer containing tomato pomace gave higher values in yield components [77,78].
Yield was statistically significantly affected by the interaction of density and fertilization. Higher values were recorded at higher densities with the use of inhibited fertilizer. Although in the lower densities the TSW was higher, the numerical superiority of plants per square meter, resulting from the highest density, managed to overcome this characteristic, with higher yields. At the same time, the use of inhibited fertilizer enhanced the yield of the crop. The use of inhibited fertilizers often leads to higher yields [79]. Similarly, growing plants at shorter sowing distances also leads to an increase in yields [33]. The results of this study seem to agree with those of other studies conducted with similar factors.
HI was higher under low density and the use of fertilizer with inhibitors. The wider sowing reduced the competition between plants, resulting in more nutrients being absorbed by the more sparsely sown plants. In this way, more nutrients were available for the low-density plants. In addition, the use of fertilizer with inhibitors provided crops with nitrogen for a longer period of time, avoiding its immediate absorption for stem grow. The interaction between these two factors improved HI. Both plant density [80] and fertilizers [81] have affected HI in flax crops. Angelopoulou et al. (2020) [82] reported an increase in HI of false flax, when organic fertilization was added.
Fertilization increased seed oil content. Nitrogen (N) is a crucial parameter for oil production in seeds. The use of fertilization increased this characteristic. Higher seed oil content leads to higher oil yields. As a result, oil yield was affected by the interaction between density and fertilization. According to previous studies [83,84], both seed oil content and oil yield were affected by plants density and fertilization in flax, while others reported that the use of organic fertilizers improved oil content and composition [85].
According to Table 5, agronomic characteristics are correlated with yield and yield components. The TSW correlates with plant height, dry weight and number of capsules, probably due to the efficiency of N in plants. Oil content and oil yield are influenced by all the parameters. For seed oil content, height and TSW seem to have the strongest correlation. Seed yield influences the oil yield, followed by the plants’ height and the seed oil content.

4. Materials and Methods

A three-year field experiment was conducted at the Agricultural University of Athens (37°59′ N and 23°42′ E; 30 m altitude), in 2023 (I), 2024 (II) and 2025 (III) (Figure 2). The experimental area was 837 m2. The soil type at the experimental field was classified as clay loam, with 29.4% clay, 35.1% silt and 35.5% sand. The pH was 7.39 (1:1 H2O). Total nitrogen (N), phosphorus (Olsen P), potassium (K) and calcium carbonate (CaCO3) were measured as 0.143%, 13.6 mg kg−1, 233 mg kg−1 and 15.34%, respectively. The level of Soil Organic Matter (SOM) was 1.67%.
Data for the weather conditions were collected by an automatic weather station (Davis Vantage Pro2 Weather Station; Davis Instruments Corporation, Hayward, CA, USA), which was located in the field. Weather data collected included mean air temperature and total rainfall, during the period of the experiment. These data are presented in Figure 3. Mean temperature was 14.4, 16.0 and 14.6 °C and total rainfall was 123.7, 174.0 and 195.4 mm for years I, II and III, respectively.
The experimental design was split plot, with two factors and four replicates. Treatments were randomly assigned within each replication. In order to account for any potential field variability, replications were arranged in blocks. Each block contained all treatments. The first factor (main plot—91 m2) was density. Two different densities were used for the experiment. The first was 500 plants per m2 (D1) and the second was 300 plants per m2 (D2). The second factor (sub-plot—21 m2) was the type of fertilizer. 174 kg ha−1 were used for urea 46-0-0 [EUROCHEM HELLAS S.A., Athens, Greece] (U) and urea with nitrification—N-((3(5)-methyl-1H-pyrazol-1-yl) methyl) acetamide (MPA; 0.07%)- and urease—N-(2-Nitrophenyl) phosphoric triamide (2-NPT; 0.035%)- inhibitor 46-0-0 [EUROCHEM HELLAS S.A., Athens, Greece] (U + UI + NI). 2784 kg ha−1 of organic fertilizer was also used. The fertilization rates were selected based on the average rate proposed by the literature [10]. The composition of the organic fertilizer was tomato pomace with compost, with N total 28.7 g kg−1, 44% organic matter, an EC of 1.76 mS cm−1, a pH of 7.38, phosphorus Olsen 15 mg kg−1 and potassium of 30 mg kg−1 The last treatment was the control (C), with no fertilization.
For the three years, sowing was performed by hand on the 25th of November. Before sowing, the fertilizers were added, and they were incorporated. Flax (Linum usitatissimum L. cv Everest) was sown in 25 and 35 cm between rows for D1 and D2, respectively. Inside the row, the distance between the seeds was 1 cm. The crop was rainfed, so there was no irrigation. Weeds were controlled manually on a weekly basis, while infestations from pests and diseases were not observed. Harvest took place on the 9th, 10th and 10th of May for years 2023 (I), 2024 (II) and 2025 (III), respectively. Harvest was performed by hand, when the seeds’ moisture was 12%.
The measurements were performed at 160 Days After Sowing (DAS) for both years, when plants reached full maturity. These measurements referred to the estimation of agronomic characteristics. Firstly, plant height was measured. For this measurement five plants per plot were randomly chosen and clipped at ground level. After height measurement, the number of capsules per plant was measured, while the number of seeds per capsule was reported by choosing three random capsules per plant. For plant biomass, four quadrats with an area of 0.25 m2 each were put randomly in every plot. The plants inside the quadrat were cut at the ground level and placed in an oven, at 80 °C for 72 h. After this, matter (DM) was measured. On the harvesting day, the plants from the whole plot were collected in order to measure the Thousand Seeds Weight (TSW) and the yield. For TSW (g) one hundred seeds were randomly chosen from each treatment, four times, and weighed. The mean value of this measurement was multiplied by 10. For the yield (kg ha−1) measurement, seeds from every treatment were weighed and multiplied, in order to calculate the yield per ha. In order to calculate the oil content, an oil extraction from 300 g of seeds per plot was performed, via a cold pressing method. According to this method, a screw expeller SPU 20 (Senta, Serbia) was used, while the extraction took place at room temperature. Plastic bottles were used in order to store the oil samples until the following day, when they were centrifuged (3500 rpm for 15 min) and filtered through a paper filter. After that, the weight of the samples was measured, and the seed oil content was calculated by the equation: oil content (%) = (mo × 100)/ms, where mo = extracted oil’s weight (g) and ms = weight of seeds’ sample (g). Oil yield was calculated by the multiplication of the yield and the oil content. Harvest Index (HI) was also measured. For the calculation of the HI was performed by the following Equation (1):
HI = (Dry weight of harvested seeds/Total dry weight of the harvested plants) × 100
For the statistical analysis, the logistic package Statistica v 7.0 (Stat Soft, 2011) was used, in order to perform a two-way analysis of variance (ANOVA) for the data. Tukey’s honestly significant difference (HSD) test was used for the multiple comparison of means, while the correlation analysis was performed using Pearson’s correlation. The level of significance was 5% (p ≤ 0.05) for all comparisons.

5. Conclusions

Fertilization and plant density are two key factors significantly affecting the performance of flax in the Mediterranean region. The present study further confirms that the optimal plant density for seed oil production in flax is 300 plants m−2. However, the results highlight the interaction between the fertilization type and the plant density. In particular, the application of inhibited fertilizers (80 kg N ha−1) in combination with an average plant density of 300 plants m−2 can improve seed and oil yield in flax by approximately 60% and 100%, respectively, compared to the control. Lastly, the use of organic amendments that include tomato pomace showed promising results, increasing oil yield by approximately 6–50% (compared to C).

Author Contributions

Conceptualization, P.S. and I.K.; methodology, P.S. and A.M.; software, P.S. and A.M.; validation, P.S. and I.K.; formal analysis, P.S., A.M. and I.R.; investigation, P.S. and A.M.; resources, P.S., A.M. and I.K.; data curation, P.S., A.M., G.P., A.F., I.R., S.K. (Stella Karydogianni) and S.K. (Stavroula Kallergi).; writing—original draft preparation, P.S. and A.M.; writing—review and editing, P.S., A.M. and I.K.; visualization, P.S. and I.K.; supervision, I.K.; project administration, P.S. and I.K. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

All data supporting the reported results are provided in the tables within the text.

Conflicts of Interest

The authors declare no conflicts of interest.

Abbreviations

The following abbreviations are used in this manuscript:
ACsAlternative crops
ALAAlpha-linolenic acid
NNitrogen
NBPTThiophosphoricriamide
DCDDicyandiamide
PGPMPlant growth promoting microorganisms
TSWThousand seeds weight
NINitrification inhibitor
UIUrease inhibitor
DDensity
HIHarvest index
PPhosphorus
KPotassium
CaCO3Calcium carbonate
SOMSoil organic matter

References

  1. Mall, R.K.; Gupta, A.; Sonkar, G. Effect of Climate Change on Agricultural Crops. In Current Developments in Biotechnology and Bioengineering, 1st ed.; Elsevier: Amsterdam, The Netherlands, 2017; pp. 23–46. [Google Scholar]
  2. Kernasiuk, Y. Global climate crisis and its impact on the development of the agricultural sector of the Ukrainian economy. Ekon. APK 2021, 28, 91–101. [Google Scholar] [CrossRef]
  3. Lehner, P.H.; Rosenberg, N.A. The climate crisis and agriculture. Env’t L. Rep. 2022, 52, 10096. [Google Scholar]
  4. Jovović, Z.; Velimirović, A.; Yaman, N. Climate and Crop Production Crisis. In Agriculture and Water Management Under Climate Change, 1st ed.; Çetin, Ö., Ed.; Springer Nature: Cham, Switzerland, 2025; pp. 1–28. [Google Scholar]
  5. Fghire, R.; Anaya, F.; Lamnai, K.; Faghire, M. Alternative Crops as a Solution to Food Security under Climate Changes. In Nutrition and Human Health: Effects and Environmental Impacts; Chatoui, H., Merzouki, M., Moummou, H., Tilaoui, M., Saadaoui, N., Brhich, A., Eds.; Springer International Publishing: Cham, Switzerland, 2022; pp. 87–98. [Google Scholar]
  6. Bilalis, D.; Roussis, I.; Fuentes, F.; Kakabouki, I.; Travlos, I. Organic agriculture and innovative crops under Mediterranean conditions. Not. Bot. Horti Agrobot. 2017, 45, 323–331. [Google Scholar] [CrossRef]
  7. Sauer, P.A.; Sullivan, P. Alternative Agronomic Crops, 2nd ed.; ATTRA: Fayetteville, AR, USA, 2000. [Google Scholar]
  8. Metz, B.; Davidson, O.R.; Bosch, P.R.; Dave, R.; Meyer, L.A. (Eds.) Climate Change 2007: Mitigation. In Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change; Cambridge University Press: Cambridge, UK; New York, NY, USA, 2007. [Google Scholar]
  9. Isleib, J. Exploring Alternative Field Crops. Michigan State University Extension: East Lansing, MI, USA, 2012. Available online: https://www.canr.msu.edu/news/exploring_alternative_field_crops (accessed on 15 August 2025).
  10. Stavropoulos, P.; Mavroeidis, A.; Papadopoulos, G.; Roussis, I.; Bilalis, D.; Kakabouki, I. On the path towards a “Greener” EU: A Mini review on Flax (Linum usitatissimum L.) as a Case Study. Plants 2023, 12, 1102. [Google Scholar] [CrossRef] [PubMed]
  11. Sarfraz, H.; Ahmad, I.Z. A systematic review on the pharmacological potential of Linum usitatissimum L.: A significant nutraceutical plant. J. Herb. Med. 2023, 42, 100755. [Google Scholar] [CrossRef]
  12. Paliwal, S.; Tripathi, M.K.; Tiwari, S.; Tripathi, N.; Payasi, D.K.; Tiwari, P.N.; Singh, K.; Yadav, R.K.; Asati, R.; Chauhan, S. Molecular advances to combat different biotic and abiotic stresses in linseed (Linum usitatissimum L.): A comprehensive review. Genes 2023, 14, 1461. [Google Scholar] [CrossRef]
  13. Vaisey-Genser, M.; Morris, D.H. Introduction: History of the Cultivation and Uses of Flaxseed. In Flax: The Genus Linum; Muir, A.D., Westcott, N.D., Eds.; CRC Press: Boca Raton, FL, USA, 2003; pp. 13–33. [Google Scholar]
  14. Malik, K.; Ahmad, F.; Gunister, E.; Nakato, T.; Mouri, E.; Muhammad, M.B.; Ali, S. A review of flax fiber reinforced thermoset polymer composites: Structure and mechanical performance. J. Nat. Fibers 2022, 19, 9656–9680. [Google Scholar] [CrossRef]
  15. Das, S.C.; La Rosa, A.D.; Goutianos, S.; Grammatikos, S.A. Flax Fibers, Their Composites and Application. In Plant Fibers, Their Composites, and Applications; Woodhead Publishing: Cambridge, UK, 2022; pp. 209–232. [Google Scholar]
  16. Tang, Z.X.; Shi, L.E.; Wang, X.M.; Dai, G.W.; Cheng, L.A.; Wan, Z.X.; He, H.; Wu, Q.; Wang, Y.B.; Jin, X.Y.; et al. Whole flaxseed-based products and their health benefits. Food Sci. Technol. Res. 2020, 26, 561–578. [Google Scholar] [CrossRef]
  17. Nowak, W.; Jeziorek, M. The role of flaxseed in improving human health. Healthcare 2023, 11, 395. [Google Scholar] [CrossRef]
  18. Wang, N.; Liu, X.; Ma, Y.; Huang, X.; Song, L.; Guo, H.; Sun, X.; Sun, X.; Hai, D.; Zhao, P.; et al. Identification of polyphenol extracts from flaxseed and study on its bacteriostatic mechanism. Food Biosci. 2025, 58, 103618. [Google Scholar] [CrossRef]
  19. Shim, Y.Y.; Kim, J.H.; Cho, J.Y.; Reaney, M.J. Health benefits of flaxseed and its peptides (linusorbs). Crit. Rev. Food Sci. Nutr. 2024, 64, 1845–1864. [Google Scholar] [CrossRef] [PubMed]
  20. Kolodziejczyk, P.; Ozimek, L.; Kozłowska, J. The Application of Flax and Hemp Seeds in Food, Animal Feed and Cosmetics Production. In Handbook of Natural Fibres; Kozłowski, R.M., Ed.; Woodhead Publishing: Cambridge, UK, 2012; pp. 329–366. [Google Scholar]
  21. Yang, J.; Wen, C.; Duan, Y.; Deng, Q.; Peng, D.; Zhang, H.; Ma, H. The composition, extraction, analysis, bioactivities, bioavailability and applications in food system of flaxseed (Linum usitatissimum L.) oil: A review. Trends Food Sci. Technol. 2021, 118, 252–260. [Google Scholar] [CrossRef]
  22. Mueed, A.; Shibli, S.; Korma, S.A.; Madjirebaye, P.; Esatbeyoglu, T.; Deng, Z. Flaxseed bioactive compounds: Chemical composition, functional properties, food applications and health benefits-related gut microbes. Foods 2022, 11, 3307. [Google Scholar] [CrossRef]
  23. Al-Madhagy, S.; Ashmawy, N.S.; Mamdouh, A.; Eldahshan, O.A.; Farag, M.A. A comprehensive review of the health benefits of flaxseed oil in relation to its chemical composition and comparison with other omega-3-rich oils. Eur. J. Med. Res. 2023, 28, 240. [Google Scholar] [CrossRef]
  24. Noreen, S.; Tufail, T.; Bader Ul Ain, H.; Ali, A.; Aadil, R.M.; Nemat, A.; Manzoor, M.F. Antioxidant activity and phytochemical analysis of fennel seeds and flaxseed. Food Sci. Nutr. 2023, 11, 1309–1317. [Google Scholar] [CrossRef]
  25. Mavroeidis, A.; Roussis, I.; Kakabouki, I. The role of alternative crops in an upcoming global food crisis: A concise review. Foods 2022, 11, 3584. [Google Scholar] [CrossRef]
  26. Outzen, M.; Thomsen, S.T.; Andersen, R.; Jakobsen, L.S.; Jakobsen, M.U.; Nauta, M.; Ravn-Haren, G.; Sloth, J.J.; Pilegaard, K.; Poulsen, M. Evaluating the health impact of increased linseed consumption in the Danish population. Food Chem. Toxicol. 2024, 183, 114308. [Google Scholar] [CrossRef]
  27. Yuan, Q.; Xie, F.; Huang, W.; Hu, M.; Yan, Q.; Chen, Z.; Zheng, Y.; Liu, L. The review of alpha-linolenic acid: Sources, metabolism, and pharmacology. Phytother. Res. 2022, 36, 164–188. [Google Scholar] [CrossRef]
  28. Hussein, Z.E.H.; Silva, J.M.; Castro, M.C.; Borges, N.E.; Saqueti, B.H.F. Optimization of Almond Beverage Enriched with Omega-3 Fatty Acids by Adding Brown Flaxseeds (Linum usitatissimum L.) Using D-Optimal Mixing Diagram Method. Food Technol. Biotechnol. 2025, 63, 274–284. [Google Scholar] [CrossRef] [PubMed]
  29. Adorian, T.J.; Pianesso, D.; Bender, A.B.B.; Speroni, C.S.; Mombach, P.I.; Kowalski, É.A.; da Silva, L.P. Fractionation of linseed and obtaining ingredients rich in protein and fibers: Alternatives for animal feed. J. Sci. Food Agric. 2022, 102, 1514–1521. [Google Scholar] [CrossRef]
  30. Debnath, S. Flax Fibre Extraction to Textiles and Sustainability: A Holistic Approach. In Sustainable Fashion and Textiles in Latin America; Gardetti, M.A., Ed.; Springer: Singapore, 2021; pp. 73–85. [Google Scholar]
  31. Ye, X.P.; Xu, M.F.; Tang, Z.X.; Chen, H.J.; Wu, D.T.; Wang, Z.Y.; Songzhen, Y.X.; Hao, J.; Wu, L.M.; Shi, L.E. Flaxseed protein: Extraction, functionalities and applications. Food Sci. Technol. 2022, 42, e22021. [Google Scholar] [CrossRef]
  32. Rossini, F.; Casa, R. Influence of sowing and harvest time on fibre flax (Linum usitatissimum L.) in the Mediterranean environment. J. Agron. Crop Sci. 2003, 189, 191–196. [Google Scholar] [CrossRef]
  33. Lloveras, J.; Santiveri, F.; Gorchs, G. Hemp and flax biomass and fiber production and linseed yield in irrigated Mediterranean conditions. J. Ind. Hemp 2006, 11, 3–15. [Google Scholar] [CrossRef]
  34. Bilalis, D.; Karkanis, A.; Pantelia, A.; Patsiali, S.; Konstantas, A.; Efthimiadou, A. Weed populations are affected by tillage systems and fertilization practices in organic flax (Linum usitatissimum L.) crop. Aust. J. Crop Sci. 2012, 6, 157–163. [Google Scholar]
  35. Kakabouki, I.; Mavroeidis, A.; Tataridas, A.; Roussis, I.; Katsenios, N.; Efthimiadou, A.; Tigka, E.; Karydogianni, S.; Zisi, C.; Folina, A.; et al. Reintroducing flax (Linum usitatissimum L.) to the Mediterranean Basin: The importance of nitrogen fertilization. Plants 2021, 10, 1758. [Google Scholar] [CrossRef]
  36. El-Gedwy, E.S.M. Effect of nitrogen fertilizer rates and plant density on straw, fiber yield and anatomical manifestations of some flax cultivars. Ann. Agric. Sci. Moshtohor 2020, 58, 700–855. [Google Scholar] [CrossRef]
  37. Heller, K.; Sheng, Q.C.; Guan, F.; Alexopoulou, E.; Hua, L.S.; Wu, G.W.; Jankauskiene, Z.; Fu, W.Y. A comparative study between Europe and China in crop management of two types of flax: Linseed and fibre flax. Ind. Crops Prod. 2015, 68, 24–31. [Google Scholar] [CrossRef]
  38. Arslanoglu, Ş.F.; Sert, S.; Şahin, H.A.; Aytaç, S.; El Sabagh, A. Yield and yield criteria of flax fiber (Linum usititassimum L.) as influenced by different plant densities. Sustainability 2022, 14, 4710. [Google Scholar] [CrossRef]
  39. Dey, P.; Mahapatra, B.S.; Negi, M.S.; Singh, S.P.; Paul, J.; Pramanick, B. Seeding density and nutrient management practice influence yield; quality and nutrient use efficiency of flax grown under sub-tropical humid Himalayan tarai. Ind. Crops Prod. 2022, 178, 114616. [Google Scholar] [CrossRef]
  40. Wu, B.; Cui, Z.; Ma, L.; Li, X.; Wang, H.; Wang, Y.; Yan, B.; Dong, H.; Gao, Y. Effects of planting density—Potassium interaction on the coordination among the lignin synthesis, stem lodging resistance, and grain yield in oil flax. Agronomy 2023, 13, 2556. [Google Scholar] [CrossRef]
  41. Scarton, V.D.B.; Carvalho, I.R.; Bandeira, W.J.A.; Pradebon, L.C.; Sangiovo, J.P.; Loro, M.V.; Huth, C. Optimum sowing density arrangement to maximize linseed agronomic performance. Rev. Delos. 2023, 16, 2927–2940. [Google Scholar] [CrossRef]
  42. Al-Obady, R.F.; Shaker, A.T. Effect of sowing dates and compound fertilizer NPK on growth and yield of flax (Linum usitatissimum L.). Basrah J. Agric. Sci. 2022, 35, 185–198. [Google Scholar] [CrossRef]
  43. Li, Y.; Wu, B.; Gao, Y.; Wu, L.; Zhao, X.; Wu, L.; Zhou, H.; Tang, J. Combination of organic and inorganic fertilizers to counteract climate change effects on cultivation of oilseed flax (Linum usitatissimum L.) using the APSIM model in arid and semiarid environments. Agronomy 2023, 13, 2995. [Google Scholar] [CrossRef]
  44. Li, X.; Gao, Y.; Cui, Z.; Zhang, T.; Chen, S.; Xiang, S.; Jia, L.; Yan, B.; Wang, Y.; Guo, L.; et al. Optimized nitrogen and potassium fertilizers application increases stem lodging resistance and grain yield of oil flax by enhancing lignin biosynthesis. J. Integr. Agric. 2024, in press. [Google Scholar] [CrossRef]
  45. Cui, Z.; Yan, B.; Gao, Y.; Wu, B.; Wang, Y.; Wang, H.; Xu, P.; Zhao, B.; Cao, Z.; Zhang, Y.; et al. Agronomic cultivation measures on productivity of oilseed flax: A review. Oppor. Chall. Sustain. 2022, 7, 53–62. [Google Scholar] [CrossRef]
  46. Afshar, R.K.; Lin, R.; Mohammed, Y.A.; Chen, C. Agronomic effects of urease and nitrification inhibitors on ammonia volatilization and nitrogen utilization in a dryland farming system: Field and laboratory investigation. J. Clean. Prod. 2018, 172, 4130–4139. [Google Scholar] [CrossRef]
  47. Skorupka, M.; Nosalewicz, A. Ammonia volatilization from fertilizer urea—A new challenge for agriculture and industry in view of growing global demand for food and energy crops. Agriculture 2021, 11, 822. [Google Scholar] [CrossRef]
  48. Swify, S.; Mažeika, R.; Baltrusaitis, J.; Drapanauskaitė, D.; Barčauskaitė, K. Modified urea fertilizers and their effects on improving nitrogen use efficiency (NUE). Sustainability 2023, 16, 188. [Google Scholar] [CrossRef]
  49. Karagöz, İ. Fertilization and fertilizer types. In Applied Soil Chemistry; John Wiley & Sons, Inc.: Hoboken, NJ, USA, 2021; pp. 123–148. [Google Scholar]
  50. Xia, M.; Mao, C.; Gu, A.; Tountas, A.A.; Qiu, C.; Wood, T.E.; Li, Y.F.; Ulmer, U.; Xu, Y.; Viasus, J.C.; et al. Solar urea: Towards a sustainable fertilizer industry. Angew. Chem. 2022, 134, e202110158. [Google Scholar] [CrossRef]
  51. Motasim, A.M.; Samsuri, A.W.; Nabayi, A.; Akter, A.; Haque, M.A.; Abdul Sukor, A.S.; Adibah, A.M. Urea application in soil: Processes, losses, and alternatives—A review. Discov. Agric. 2024, 2, 42. [Google Scholar] [CrossRef]
  52. Gastal, F.; Lemaire, G.; Durand, J.L.; Louarn, G. Quantifying Crop Responses to Nitrogen and Avenues to Improve Nitrogen-Use Efficiency. In Crop Physiology; Sadras, V.O., Calderini, D.F., Eds.; Academic Press: London, UK, 2015; pp. 161–206. [Google Scholar]
  53. Srivastavaa, N.; Agnihotrib, N. Excessive use of urea is responsible for nitrogen pollution in India: A systematic review. Biopsectra 2022, 17, 83–88. [Google Scholar]
  54. Masjedi, S.K.; Kazemi, A.; Moeinnadini, M.; Khaki, E.; Olsen, S.I. Urea production: An absolute environmental sustainability assessment. Sci. Total Environ. 2024, 908, 168225. [Google Scholar] [CrossRef]
  55. Byrne, M.P.; Tobin, J.T.; Forrestal, P.J.; Danaher, M.; Nkwonta, C.G.; Richards, K.; Cummins, E.; Hogan, S.A.; O’Callaghan, T.F. Urease and nitrification inhibitors—As mitigation tools for greenhouse gas emissions in sustainable dairy systems: A review. Sustainability 2020, 12, 6018. [Google Scholar] [CrossRef]
  56. Torralbo, F.; Boardman, D.; Houx, J.H., III; Fritschi, F.B. Distinct enhanced efficiency urea fertilizers differentially influence ammonia volatilization losses and maize yield. Plant Soil 2022, 475, 551–563. [Google Scholar] [CrossRef]
  57. Snyder, C.S. Enhanced nitrogen fertiliser technologies support the ‘4R’concept to optimise crop production and minimise environmental losses. Soil Res. 2017, 55, 463–472. [Google Scholar] [CrossRef]
  58. Klimczyk, M.; Siczek, A.; Schimmelpfennig, L. Improving the efficiency of urea-based fertilization leading to reduction in ammonia emission. Sci. Total Environ. 2021, 771, 145483. [Google Scholar] [CrossRef]
  59. Mureșan, C.; Russu, F.; Ghețe, A.; Popescu, M.; Urdă, C.; Cindea, M.D.; Ionescu, N.; Duda, M.M.; Bartha, S. The Influence of Green Manures on Production and Quality of Flax Seeds. Rom. Agric. Res. 2021, 38, 292–299. [Google Scholar] [CrossRef]
  60. Fallah, M.; Hadi, H.; Amirnia, R.; Hasanzadeh Gorttapeh, A. Effect of green manure residues and fertilizer sources on agro-physiological characteristics of flax seed in irrigation termination at flowering stage. J. Crop Improv. 2021, 23, 141–154. [Google Scholar]
  61. Xu, P.; Gao, Y.; Cui, Z.; Wu, B.; Yan, B.; Wang, Y.; Wen, M.; Wang, H.; Ma, X.; Wen, Z. Application of organic fertilizers optimizes water consumption characteristics and improves seed yield of oilseed flax in semi-arid areas of the Loess Plateau. Agronomy 2023, 13, 1755. [Google Scholar] [CrossRef]
  62. Ma, X.; Gao, Y.; Wu, B.; Ma, X.; Wang, Y.; Yan, B.; Cui, Z.; Wen, M.; Zhang, X.; Wang, H. Organic Manure Significantly Promotes the Growth of Oilseed Flax and Improves Its Grain Yield in Dry Areas of the Loess Plateau of China. Agronomy 2023, 13, 2304. [Google Scholar] [CrossRef]
  63. Ma, X.; Gao, Y.; Ma, X.; Wu, B.; Yan, B.; Li, Y.; Wang, Y.; Xu, P.; Wen, M.; Wang, H.; et al. Effect of Different Types of Organic Manure on Oil and Fatty Acid Accumulation and Desaturase Gene Expression of Oilseed Flax in the Dry Areas of the Loess Plateau of China. Agronomy 2024, 14, 381. [Google Scholar] [CrossRef]
  64. Omer, A.M.; Osman, M.S.; Badawy, A.A. Inoculation with Azospirillum brasilense and/or Pseudomonas geniculata reinforces flax (Linum usitatissimum) growth by improving physiological activities under saline soil conditions. Bot. Stud. 2022, 63, 15. [Google Scholar] [CrossRef]
  65. Dmitrevskaya, I.I.; Grigoryeva, M.V.; Belopukhov, S.L.; Zharkikh, O.A.; Seregina, I.I.; Osipova, A.V. Influence of new phytoregulators on oilseed flax growth, development, yielding capacity, and product quality. Braz. J. Biol. 2022, 82, e264870. [Google Scholar] [CrossRef]
  66. Mourouzidou, S.; Ntinas, G.K.; Tsaballa, A.; Monokrousos, N. Introducing the power of plant growth promoting microorganisms in soilless systems: A promising alternative for sustainable agriculture. Sustainability 2023, 15, 5959. [Google Scholar] [CrossRef]
  67. Del Valle, M.; Cámara, M.; Torija, M.E. Chemical characterization of tomato pomace. J. Sci. Food Agric. 2006, 86, 1232–1236. [Google Scholar] [CrossRef]
  68. Achmon, Y.; Harrold, D.R.; Claypool, J.T.; Stapleton, J.J.; VanderGheynst, J.S.; Simmons, C.W. Assessment of tomato and wine processing solid wastes as soil amendments for biosolarization. Waste Manag. 2016, 48, 156–164. [Google Scholar] [CrossRef] [PubMed]
  69. Kakabouki, I.; Roussis, I.; Krokida, M.; Mavroeidis, A.; Stavropoulos, P.; Karydogianni, S.; Beslemes, D.; Tigka, E. Comparative Study Effect of Different Urea Fertilizers and Tomato Pomace Composts on the Performance and Quality Traits of Processing Tomato (Lycopersicon esculentum Mill.). Plants 2024, 13, 1852. [Google Scholar] [CrossRef] [PubMed]
  70. Khaveh, M.T.; Alahdadi, I.; Hoseinzadeh, B.E. Effect of slow-release nitrogen fertilizer on morphologic traits of corn (Zea mays L.). J. Bus. Econ. Stat. 2015, 6, 546–559. [Google Scholar]
  71. Kakabouki, I.; Efthimiadou, A.; Folina, A.; Zisi, C.; Karydogianni, S. Effect of different tomato pomace compost as organic fertilizer in sweet maize crop. Commun. Soil. Sci. Plant Anal. 2020, 51, 2858–2872. [Google Scholar] [CrossRef]
  72. Abdulazeez, S.D.; Salih, R.F. Growth and yield of linseed (Linum usitatissimum L.) enhanced through adding organic and inorganic fertilizers. J. Med. Ind. Plants 2025, 3, 80–89. [Google Scholar] [CrossRef]
  73. Wu, Q.; Wang, Y.-H.; Ding, Y.-F.; Tao, W.-K.; Gao, S.; Li, Q.-X.; Li, W.-W.; Liu, Z.-H.; Li, G.-H. Effects of different types of slow-and controlled-release fertilizers on rice yield. Integr. Agric. 2021, 20, 1503–1514. [Google Scholar]
  74. Soethe, G.; Feiden, A.; Bassegio, D.; Santos, R.F.; de Souza, S.N.M.; Secco, D. Sources and rates of nitrogen in the cultivation of flax. Afr. J. Agric. Res. 2013, 8, 2249–2254. [Google Scholar] [CrossRef]
  75. Abdel-Kader, E.M.A.; Mousa, A.M.A. Effect of nitrogen fertilizer on some flax varieties under two different location conditions. J. Plant Prod. 2019, 10, 37–44. [Google Scholar] [CrossRef]
  76. Rajanna, B.; Gangaprasad, S.; Shanker, G.I.; Dushyantha, K.B.M.; Girjesh, G.K.; Sathish, K.M. Genetic variability, heritability, and genetic advance of yield components and oil quality parameters in linseed (Linum usitatissimum L.). Int. J. Chem. Stud. 2020, 8, 1768–1771. [Google Scholar] [CrossRef]
  77. Cheng, B.; Wang, J.; Zhang, H.-M.; Liu, H.; A, B.-y.-s.; Ge, N.; Liu, J.-F.; Feng, T. Biology organic fertilizer affects the quality and yield of flax under different irrigation regumes. Pak. J. Agric. Sci. 2023, 60, 429–436. [Google Scholar] [CrossRef]
  78. Kakabouki, I.; Folina, A.; Efthimiadou, A.; Karydogianni, S.; Zisi, C.; Kouneli, V.; Kapsalis, N.C.; Katsenios, N.; Travlos, I. Evaluation of processing tomato pomace after composting on soil properties, yield, and quality of processing tomato in Greece. Agronomy 2021, 11, 88. [Google Scholar] [CrossRef]
  79. Ghafoor, I.; Habib-ur-Rahman, M.; Ali, M.; Afzal, M.; Ahmed, W.; Gaiser, T.; Ghaffar, A. Slow-release nitrogen fertilizers enhance growth, yield, NUE in wheat crop and reduce nitrogen losses under an arid environment. Environ. Sci. Pollut. Res. Int. 2021, 28, 43528–43543. [Google Scholar] [CrossRef] [PubMed]
  80. Khan, M.B.; Yasir, T.A.; Aman, M. Growth and yield comparison of different linseed (Linum usitatissimum L.) genotypes planted at different row spacing. J. Agric. Biol. 2005, 7, 515–517. [Google Scholar]
  81. Chen, J.; Ye, C.L.; Li, J.J.; Luo, J.J.; Yan, X.C.; Wang, W.; Wang, L. Effect of seeding rate+ fertilization amount on the growth, yield and harvest index of flax under water stress. J. Agric. Sci. Technol. 2022, 22, 139–148. [Google Scholar]
  82. Angelopoulou, F.; Tsiplakou, E.; Bilalis, D. Tillage intensity and compost application effects on organically grown camelina productivity, seed and oil quality. Not. Bot. Horti Agrobot. 2020, 48, 2153–2166. [Google Scholar] [CrossRef]
  83. Mitra, S.; Adhikary, B.; Islam, S.; Nag, S.K.; Alam, N.M.; Mazumdar, S.P.; Kumar, M.; Kumar Singh, A.; Datta, D.; Souvar Kar, C.; et al. Changes in seed yield and oil quality of flax (Linum usitatissimum L.) for industrial use in response to nitrogen and potassium fertilization. Arch. Agron. Soil Sci. 2023, 69, 3619–3636. [Google Scholar] [CrossRef]
  84. El-Seidy, E.S.; Abou-Zied, T.; Hassan, A.; Assar, E.M. Effect of plant densities and genotypes on flax agronomic traits. 2-seed yield, oil yield, fiber yield and its components. J. Prod. Dev. 2009, 14, 129–145. [Google Scholar] [CrossRef]
  85. Jogić, V.; Džafić, S.; Nikitović, J. Effects of fertilization on the fatty acid content of oil flax. Int. J. Adv. Agric. Sci. Technol. 2018, 5, 21–27. [Google Scholar]
Plants 14 02891 g001
Figure 1. Effect of plants’ density and type of fertilization on flax: (a) yield (b) Harvest Index (HI) (c) oil yield. Values represent the three-year mean (2023–2025). Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “**” and “***” indicates significance at the p < 0.01 and p < 0.001 levels, respectively.
Figure 1. Effect of plants’ density and type of fertilization on flax: (a) yield (b) Harvest Index (HI) (c) oil yield. Values represent the three-year mean (2023–2025). Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “**” and “***” indicates significance at the p < 0.01 and p < 0.001 levels, respectively.
Plants 14 02891 g001
Plants 14 02891 g002
Figure 2. The experimental field of flax at the: (a) growth stage and (b) flowering stage.
Figure 2. The experimental field of flax at the: (a) growth stage and (b) flowering stage.
Plants 14 02891 g002
Plants 14 02891 g003
Figure 3. Meteorological data during the experimental period.
Figure 3. Meteorological data during the experimental period.
Plants 14 02891 g003
Table 1. Effect of fertilization on agronomic characteristics.
Table 1. Effect of fertilization on agronomic characteristics.
Height (cm)Dry Weight (g plant−1)Number of Capsules
Density
FertilizationD1D2D1D2D1D2
C56.18 ± 0.28 a56.14 ± 0.66 a1.14 ± 0.1 a1.69 ± 0.13 a13.11 ± 0.91 a15.38 ± 1.19 a
I64.26 ± 0.35 c64.47 ± 0.18 c1.38 ± 0.15 ab2.43 ± 0.11 bc16.95 ± 0.52 b19.48 ± 0.33 b
O62.61 ± 0.17 b61.53 ± 0.37 b1.36 ± 0.11 ab2.1 ± 0.21 b15.58 ± 0.32 b17.72 ± 0.57 ab
U64.86 ± 0.11 c64.52 ± 0.31 c1.48 ± 0.07 b2.64 ± 0.08 c16.14 ± 0.9 b18.94 ± 1.33 b
FYEAR0.01 ns1.49 ns2.43 ns
FDENSITY1.4 ns99.50 ***14.84 **
FFERTILIZATION222.13 ***9.93 ***7.53 **
FY×D0 ns2.86 ns0.05 ns
FY×F0.16 ns0.94 ns0.05 ns
FD×F1.11 ns2.56 ns0.05 ns
FY×D×F0.07 ns0.89 ns0.04 ns
Values represent the three-year mean (2023–2025). Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “**” and “***” indicates significance at the p < 0.01 and p < 0.001 levels, respectively.
Table 2. Effect of plants’ density on dry weight, number of capsules and TSW.
Table 2. Effect of plants’ density on dry weight, number of capsules and TSW.
Dry Weight (g plant−1)Number of CapsulesThousand Seeds Weight (g)
Density
FertilizationD1D2D1D2D1D2
C1.14 ± 0.1 a1.69 ± 0.13 b13.11 ± 0.91 ns15.38 ± 1.19ns4.99 ± 0.14a5.72 ± 0.31b
I1.38 ± 0.15 a2.43 ± 0.11 b16.95 ± 0.52 a19.48 ± 0.33b7.03 ± 0.19ns7.28 ± 0.15ns
O1.36 ± 0.11 a2.1 ± 0.21 b15.58 ± 0.32 a17.72 ± 0.57b6.42 ± 0.37ns6.83 ± 0.08ns
U1.48 ± 0.07 a2.64 ± 0.08 b16.14 ± 0.9 ns18.94 ± 1.33ns6 ± 0.13ns6.23 ± 0.08ns
FYEAR1.49 ns2.43 ns0.76 ns
FDENSITY99.50 ***14.84 **6.67 *
FFERTILIZATION9.93 ***7.53 **23.57 ***
FY×D2.86 ns0.05 ns0.04 ns
FY×F0.94 ns0.05 ns0.04 ns
FD×F2.56 ns0.05 ns0.55 ns
FY×D×F0.89 ns0.04 ns0.06 ns
Values represent the three-year mean (2023–2025). Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “*”, “**” and “***” indicates significance at the p < 0.05, p < 0.01 and p < 0.001 levels, respectively.
Table 3. Effect of fertilization on yield components.
Table 3. Effect of fertilization on yield components.
Seeds per CapsuleThousand Seeds Weight (g)
Density
FertilizationD1D2D1D2
C9.29 ± 0.24 ns9.31 ± 0.15 ns4.99 ± 0.14 a5.72 ± 0.31 a
I9.78 ± 0.11 ns9.85 ± 0.11 ns7.03 ± 0.19 c7.28 ± 0.15 b
O9.38 ± 0.15 ns9.43 ± 0.15 ns6.42 ± 0.37 bc6.83 ± 0.08 b
U9.71 ± 0.17 ns9.87 ± 0.45 ns6 ± 0.13 b6.23 ± 0.08 a
FYEAR0.23 ns0.76 ns
FDENSITY0.21 ns6.67 *
FFERTILIZATION2.50 ns23.57 ***
FY×D0.37 ns0.04 ns
FY×F0.13 ns0.04 ns
FD×F0.04 ns0.55 ns
FY×D×F0.24 ns0.06 ns
Values represent the three-year mean (2023–2025). Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “*” and “***” indicates significance at the p < 0.05 and p < 0.001 levels, respectively.
Table 4. Effect of the type of fertilizer on seed oil content (%).
Table 4. Effect of the type of fertilizer on seed oil content (%).
Oil Content (%)
Density
FertilizationD1D2
C26.51 ± 1 a27.4 ± 0.94 a
I38.18 ± 0.71 b39.2 ± 0.58 b
O37.39 ± 0.29 b38.18 ± 0.76 b
U39.23 ± 0.95 b38.71 ± 0.64 b
FYEAR0.12 ns
FDENSITY0.87 ns
FFERTILIZATION97.08 ***
FY×D0.10 ns
FY×F0.31 ns
FD×F0.37 ns
FY×D×F0.11 ns
Values represent the three-year mean (2023–2025). Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “***” indicates significance at the p < 0.001 levels.
Table 5. Correlation coefficients between the agronomic characteristics, the yield and the yield components of flax crop.
Table 5. Correlation coefficients between the agronomic characteristics, the yield and the yield components of flax crop.
HeightDry WeightNumber of CapsulesSeeds per CapsuleTSWYieldHIOil ContentOil Yield
Height 0.30 **0.39 ***0.27 **0.52 ***0.37 ***0.37 ***0.82 ***0.75 ***
Dry weight 0.39 ***0.12 ns0.33 ***0.02 ns0.35 ***0.34 ***0.23 *
Number of capsules 0.04 ns0.31 **0.10 ns0.35 ***0.40 ***0.33 **
Seeds per capsule 0.15 ns0.16 ns0.02 ns0.24 *0.27 *
TSW 0.19 ns0.45 ***0.58 ***0.49 ***
Yield 0.27 **0.19 *0.81 ***
HI 0.36 ***0.41 ***
Oil content 0.72 ***
Oil yield
Different letters within the same column indicate statistically significant differences at p = 0.05 significance level. The symbol “ns” indicates non statistically significant differences, while the symbols “*”, “**” and “***” indicates significance at the p < 0.05, p < 0.01 and p < 0.001 levels, respectively.
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Stavropoulos, P.; Mavroeidis, A.; Folina, A.; Roussis, I.; Kallergi, S.; Karydogianni, S.; Papadopoulos, G.; Kakabouki, I. Effects of Plant Density and Fertilization on Agronomic Traits and Yield of Flax (Linum usitatissimum L.). Plants 2025, 14, 2891. https://doi.org/10.3390/plants14182891

AMA Style

Stavropoulos P, Mavroeidis A, Folina A, Roussis I, Kallergi S, Karydogianni S, Papadopoulos G, Kakabouki I. Effects of Plant Density and Fertilization on Agronomic Traits and Yield of Flax (Linum usitatissimum L.). Plants. 2025; 14(18):2891. https://doi.org/10.3390/plants14182891

Chicago/Turabian Style

Stavropoulos, Panteleimon, Antonios Mavroeidis, Antigolena Folina, Ioannis Roussis, Stavroula Kallergi, Stella Karydogianni, George Papadopoulos, and Ioanna Kakabouki. 2025. "Effects of Plant Density and Fertilization on Agronomic Traits and Yield of Flax (Linum usitatissimum L.)" Plants 14, no. 18: 2891. https://doi.org/10.3390/plants14182891

APA Style

Stavropoulos, P., Mavroeidis, A., Folina, A., Roussis, I., Kallergi, S., Karydogianni, S., Papadopoulos, G., & Kakabouki, I. (2025). Effects of Plant Density and Fertilization on Agronomic Traits and Yield of Flax (Linum usitatissimum L.). Plants, 14(18), 2891. https://doi.org/10.3390/plants14182891

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop