Current IssueEditorial BoardOnline First ArticlesArchive
Current IssueEditorial BoardOnline First ArticlesArchive

Full Research Article

Evaluation of Salt Tolerance Mechanisms in Common Bean (Phaseolus vulgaris L.) Genotypes Exposed to Sodium Chloride and Sodium Sulfate: Morphological and Biochemical Perspectives

Ş
Şefik Tunahan Çengel1
0009-0003-0336-6825
B
Barış Alaca2,*
0000-0001-7542-6514
S
Sümeyye İslam1
0009-0004-5821-2951
G
Gözde Hafize Yıldırım1
0000-0002-0557-6442
E
Erkan Özata2
0000-0002-4646-6426
1Recep Tayyip Erdoğan University, Faculty of Agriculture, Department of Field Crops, Rize/Türkiye.
2Black Sea Agricultural Research Institute, Field Crops Departments, Samsun, Türkiye.

  • Submitted22-01-2026|

  • Accepted23-02-2026|

  • First Online 10-03-2026|

  • doi 10.18805/LRF-933

ABSTRACT

Background: Common bean is a nutritionally important crop, but increasing soil salinity threatens seedling establishment and productivity.

Methods: This greenhouse pot study compared early-stage morphological and biochemical responses of two common bean genotypes (G3 and G13) exposed to two salt types (NaCl and Na2SO4) at two concentrations (20 and 40 mM), alongside a non-saline control. Plant height, biomass traits, leaf area, SPAD chlorophyll index, photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll, carotenoids), chlorophyll a/b ratio and proline were assessed.

Result: Salt treatments influenced SPAD and pigment-related traits, whereas effects on growth traits and proline were smaller or less consistent under the tested conditions. Genotype-dependent differences were observed across multiple traits. Overall, pigment traits may be useful for early-stage screening of salt responses under controlled conditions; however, conclusions should be interpreted cautiously given the limited genotype set.

INTRODUCTION

Global climate change, together with increasing drought and salinity stress, poses a serious threat to agricultural production (Kumar et al., 2025). Soil salinity, driven in part by inadequate irrigation and drainage, is expanding in many regions and remains a major soil-degradation problem limiting crop performance and yield (Yavuzlar et al., 2021). It is considered one of the most critical environmental constraints to plant growth, particularly in arid and semi-arid ecosystems (Temizgül, 2025).
       
At the plant level, salinity suppresses photosynthesis, disrupts metabolic and enzymatic processes and induces oxidative stress, ultimately leading to growth and yield losses (Borromeo et al., 2024). These effects are reflected in measurable morphological, physiological and biochemical changes (Kıpçak et al., 2019). Plants respond through ion exclusion or vacuolar sequestration, osmotic adjustment and activation of antioxidant defense systems (Kumar et al., 2025; Zhang et al., 2024). Early developmental stages are particularly informative for detecting stress impacts within a short time frame (Zhu et al., 2020).
       
Common bean (Phaseolus vulgaris L.) is an important food legume and improving its performance under salinity is relevant for both production stability and breeding. However, salinity studies frequently rely on NaCl alone, although field salinity may be chloride-or sulfate-dominated. Comparing NaCl and Na2SO4 can therefore provide a more accurate understanding of salt-tolerance mechanisms (Zhou et al., 2023). Linking salt type and intensity to measurable traits and integrating morphological and biochemical indicators strengthens screening approaches, while leaf structural and micromorphological descriptors may provide additional support. Trait-based screening can complement molecular marker and genome-editing strategies for developing stress-tolerant cultivars and enhancing food security (Fu and Yang, 2023; Priyadharshini et al., 2019; Kouki et al., 2021; Chaitanya et al., 2014).
       
Few studies have compared chloride- and sulfate-dominated salinity at the early seedling stage using combined pigment profiling and multivariate integration. Therefore, this study compared early morphological and biochemical responses of two common bean genotypes under two concentrations of NaCl and Na2SO4. We hypothesized that (i) pigment traits would respond rapidly to increasing salinity and (ii) genotype-specific differences would be detectable in pigment and osmotic-adjustment traits under controlled greenhouse conditions.

MATERIALS AND METHODS

Plant material and experimental design
 
The study was conducted in 2025 under greenhouse conditions at the Faculty of Agriculture, Recep Tayyip Erdoğan University, to evaluate the responses of two common bean candidate lines (Genotype 3 and Genotype 13) provided and coded by the national seed registration authority. Codes were retained for traceability and no salt-tolerant or -sensitive reference cultivars were included; thus, results reflect comparative responses under experimental conditions. Genotype 13 is bush-type with ~13 cm flat yellow pods, whereas Genotype 3 has white seeds (~8 mm) and high adaptability.
       
Treatments included: control, NaCl 20 mM (1.75 g/2 L) and 40 mM (3.51 g/2 L) and Na2SO4 20 mM (4.26 g/2 L) and 40 mM (8.52 g/2 L). Plants were grown in 2-L pots filled with sterile peat (pH 6.0; 1.0 g L-1 fertilizer), with five seedlings per pot. The experiment followed a 2 (genotype) × 5 (salt) factorial design with three replications; three pots per combination were used and the pot was considered the experimental unit (Fig 1). Salt solutions were applied once at 10 DAS after a 1-day irrigation pause and respective solutions were maintained for 30 days (controls received water). Measurements were taken 30 days after treatment. Data were averaged at the pot level to avoid pseudo-replication. Measured traits included plant height, SPAD, green/dry weight, leaf area, chlorophyll a and b, total chlorophyll, total carotenoids, chlorophyll a/b ratio and proline.

Fig 1: Greenhouse experimental setup showing common bean (Phaseolus vulgaris L.) plants subjected to five salinity treatments (Control, NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM).


 
Biochemical analysis
 
Photosynthetic pigments (total chlorophyll, chlorophyll a and b and total carotenoids) were quantified spectrophotometrically using the Arnon method (Arnon, 1949) and proline (µmol g-1 FW) was determined following Bates (1973) using the acid-ninhydrin assay with toluene extraction and a standard curve at 520 nm (Fig 2-3).

Fig 2: Overview of the laboratory procedures used for chlorophyll and carotenoid extraction in common bean leaves.



Fig 3: Laboratory workflow for proline determination in common bean leaves.


 
Statistical analysis
 
Statistical analyses were performed in R (lme4; Bates et al., 2015) using a two-factor mixed model with genotype, salt treatment and their interaction as fixed effects and replication as a random effect (pot = experimental unit); significant effects (p<0.05) were followed by Tukey’s HSD for mean separation.

RESULTS AND DISCUSSION

Correlation analysis showed strong positive relationships among pigment-related traits (Fig 4). Total chlorophyll was strongly correlated with chlorophyll a (r>0.90, p<0.001), chlorophyll b (r>0.95, p<0.001) and total carotenoids (r = 0.98, p<0.001). Chlorophyll a and chlorophyll b were also positively correlated.

Fig 4: Correlation matrix illustrating pairwise relationships among morphological, physiological and biochemical traits of common bean plants exposed to different salinity treatments.


       
Proline showed positive correlations with green weight (r = 0.40) and leaf area (r = 0.66, p<0.05). Correlations between proline and chlorophyll-related parameters were weak (r<0.20). Plant height showed low negative correlations with other traits (ranging from -0.05 to -0.30). Leaf area and chlorophyll (SPAD) values were positively correlated (p<0.01).
 
Principal component analysis (PCA)
 
PCA separated treatments along PC1–PC2 based on combined morphological and biochemical variation (Fig 5). Growth/biomass traits loaded mainly on one axis, whereas pigment/biochemical variables loaded on the other. Pigment vectors were long and similarly oriented, while proline pointed in a distinct direction. Controls clustered near pigment variables; Na2SO4 40 mM separated and aligned with biomass traits and proline. NaCl and Na2SO4 treatments diverged and Na2SO4 20 mM was close to NaCl 40 mM in associations with leaf area and growth traits.

Fig 5: Principal component biplot (PC1 vs. PC2) illustrating the multivariate response of common bean plants to five salinity treatments: Control (0 mM), NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM.


 
Pigment traits
 
Pigment traits differed among treatments (Fig 6; Table 2-3): controls showed the highest values and reductions increased with salinity, particularly at 40 mM. The chlorophyll a/b ratio varied, with higher values under some salt treatments (notably Na2SO4 40 mM). Low-salt treatments occasionally matched or slightly exceeded control values, but both salts at 40 mM reduced pigments overall.

Fig 6: Tukey HSD compact letter display (CLD) for six pigment-related traits of common bean plants subjected to five salt treatments: Control (0 mM), NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM.


 
Hierarchical clustering
 
Clustering grouped treatments into high-salt (Na2SO4 40 mM, NaCl 40 mM) vs control/low-salt (control, Na2 SO4 20 mM, NaCl 20 mM) clusters (Fig 7). Na2SO4 40 mM showed lower dry weight, green weight and SPAD with higher proline; NaCl 40 mM showed the lowest pigment traits. Pigments clustered together, whereas proline formed a separate cluster. Genotypes separated (Fig 8): G3 had higher pigments, proline and green/dry weight, while plant height was not higher; G13 showed lower values.

Fig 7: Z-score normalized hierarchical clustered heatmap of mean trait values across five salinity treatments: Control (0 mM), NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM.



Fig 8: Z-score normalized hierarchical clustered heatmap comparing the physiological, biochemical and pigment-related traits of genotypes G3 and G13.


 
Agronomic traits
 
Plant height was not affected by treatments (p = 0.886; 35.35-39.97 cm) (Table 1). SPAD was significantly influenced (p = 0.002), with the highest value at 40 mM Na2 SO4 (34.45) and the lowest at 20 mM NaCl (28.32). Green weight did not differ among treatments (p = 0.435; 0.38-0.47 g). Genotype effects were significant for plant height (p = 0.001) and green weight (p = 0.005) (Table 1).

Table 1: Significance levels for plant height, chlorophyll (SPAD) and green weight in bean genotypes under different salt-stress treatments.


       
Dry weight was not treatment-significant (p = 0.603; 0.06-0.12 g; highest at 40 mM Na2SO4) (Table 2). Leaf area was not affected by treatments (p = 0.131; 20.50-27.79 cm²), but genotype effects were significant (p = 0.002).

Table 2: Significance levels for dry weight, leaf area and chlorophyll a in bean genotypes under different salt-stress treatments.


       
Pigment traits (Table 2-3) generally declined at higher salinity; chlorophyll a was relatively higher at 20 mM NaCl (Table 2), whereas chlorophyll b was lower at 20 mM Na2SO4 and 40 mM NaCl (Table 3). Total chlorophyll and carotenoids decreased at higher salt levels. Proline did not differ among treatments (Table 4), but genotype effects were significant for pigments and proline (Table 2-4).

Table 3: Significance levels for chlorophyll b, total carotenoids and total chlorophyll in bean genotypes under different salt-stress treatments.



Table 4: Significance levels for chlorophyll a/b ratio and proline in bean genotypes under different salt-stress treatments.


       
Multivariate analyses indicate that salt stress modifies common bean performance through coordinated shifts in photosynthetic pigments and more variable responses in growth and osmotic traits. This pattern supports the view that salinity acts through partially independent physiological pathways, with photosynthesis, biomass accumulation and osmotic adjustment differing according to salt type, stress intensity and genotype (Hasan et al., 2016; Zhu et al., 2020; Mir et al., 2024).
       
The correlation matrix (Fig 4) showed strong clustering among pigment traits, with total chlorophyll strongly and positively associated with chlorophyll a, chlorophyll b and total carotenoids. This suggests that the pigment system functions as an integrated unit under salinity, consistent with the protective roles of chlorophylls and carotenoids in maintaining photosystem integrity (Mir et al., 2024). Previous studies report greater sensitivity of chlorophyll a and overall chlorophyll decline under increasing salinity (Aşcı et al., 2021; Kibar et al., 2020) and the present results indicate that pigment reductions occur in a coordinated rather than isolated manner.
       
Proline related positively to green weight and leaf area but weakly to pigment traits, indicating its accumulation isn’t merely due to pigment decline and may be controlled by different pathways affected by genotype and stress duration. (Mir et al., 2024). The linkage between leaf area and chlorophyll status, as well as the positive association between leaf area and SPAD values, supports coordinated variation in leaf development and chlorophyll density under stress (Zhang et al., 2024). Compensatory physiological adjustments may partly explain why morphological correlations were weaker than pigment correlations (Karakaş et al., 2019).
       
PCA (Fig 5) showed treatment responses driven by stress intensity and salt type. Separation along growth/biomass and pigment/biochemical axes indicates salinity disrupts photosynthesis and prompts adaptive changes. (Hasan et al., 2016; Zhu et al., 2020). The control group’s proximity to pigment vectors reflects expected pigment decline under salinity (Zhang et al., 2024; Aşcı et al., 2021). Divergence between NaCl and Na2SO4 indicates partially distinct metabolic reorganization pathways (Levitt, 1985). The proximity of 20 mM Na2SO4 and 40 mM NaCl in certain morphological associations suggests that once stress thresholds are exceeded, different salts may impose comparable growth constraints while operating through different biochemical routes (Mi et al., 2024).
       
Na2SO4 (40 mM) aligned with proline and biomass variables, indicating disrupted homeostasis and potential water and nutrient uptake limitations. (Farzana et al., 2021). In contrast, stronger pigment depletion under NaCl is consistent with higher photo-oxidative pressure and direct effects on chlorophyll stability (Zhang et al., 2024; Aşcı et al., 2021). The synchronized pigment vectors versus the proline direction support independent regulation of osmotic adjustment and pigment maintenance. (Mir et al., 2024).
       
Controls showed the highest pigment values, while high salinity significantly reduced them, confirming chlorophylls and carotenoids are highly responsive to salt stress. (Mir et al., 2024; Zong et al., 2021). More pronounced NaCl losses align with inhibited chlorophyll synthesis and faster pigment degradation. (Zhang et al., 2024; Emirzeoğlu and Başak, 2020). Shifts in the chlorophyll a/b ratio suggest stress-driven restructuring of light-harvesting complexes (Kaymak and Acar, 2020; Tuna and Eroğlu, 2017; Elsiddig et al., 2023). Slight low-salinity increases may indicate hormesis (Mankar et al., 2021), while higher concentrations harm pigment biosynthesis and photosystem II stability. (Fitzner et al., 2023; Zhang et al., 2024). Thus, pigment traits are particularly informative for early screening, although multiple pigment parameters should be integrated for robust evaluation (Mi et al., 2024).
       
Hierarchical clustering (Fig 7) separated high- from low-salt treatments, highlighting concentration as the dominant driver (Fidan and Ekincialp, 2017). Within the high-salt cluster, Na2SO4 (40 mM) showed lower biomass and SPAD but higher proline, while NaCl (40 mM) caused stronger pigment suppression, indicating different stress signatures of sulfate-and chloride-based salinity. (Elsiddig et al., 2023; Farzana et al., 2021; Mir et al., 2024). Similar growth reductions under salinity have been widely reported (Fidan and Ekincialp, 2020; Kibar et al., 2020; Temizgül, 2025).
       
Although genotype-dependent responses to salinity are documented (Aini et al., 2014), this study included only two genotypes; findings should be seen as genotype-specific, not generalizable. Differences in pigment and biomass traits indicate genetic background influences photosynthetic stability and biomass partitioning under salt stress. Because salt tolerance is polyfactorial, integrating morphological and biochemical traits is essential, but broader conclusions need validation with more genotypes sets (Mi et al., 2024).

CONCLUSION

Under greenhouse pot conditions, salt treatments primarily influenced pigment-related traits and the SPAD index, indicating early sensitivity of the photosynthetic apparatus to both NaCl- and Na2SO4-dominated salinity. Growth traits showed smaller or less consistent treatment effects, while genotype differences were evident across multiple traits. Proline responses were genotype-dependent and did not present a consistent treatment-driven pattern under the exposure conditions used. Because only two genotypes were evaluated and the experiment was conducted under controlled greenhouse conditions, broader breeding conclusions should be interpreted cautiously. Future work should validate screening traits using larger genotype panels and sustained salinity regimes across environments.

ACKNOWLEDGEMENT

Authors declare that no funds, grants, or other support were received during the preparation of this manuscript.
 
Disclaimers
 
The views and conclusions expressed in this article are solely those of the authors and do not necessarily represent the views of their affiliated institutions. The authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.

CONFLICT OF INTEREST

The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.

REFERENCES


  1. Aini, N., Syekhfani, S., Yamika, W.S.D., Purwaningrahayu, R.D. and Setiawan, A. (2014). Growth and physiological characteristics of soybean genotypes (Glycine max L.) toward salinity stress. Agrivita Journal of Agricultural Science. 36(3): 201-209. https://doi.org/10.17503/ agrivita-2014-36-3-201-209.

  2. Arnon, D.I. (1949). Copper enzymes in isolated chloroplasts, polyphenoxidase in Beta vulgaris. Plant Physiol. 24: 1-15.

  3. Aşcı, Ö.Ö., Saral, M.A. and Arıcı, Y.K. (2021). Tuz stresinin börülcede bazı fizyolojik özellikler ve mineral madde oranlarına etkisi. Uluslararası Tarım ve Yaban Hayatı Bilimleri Dergisi. 7(2): 297-305. https://doi.org/10.24180/ ijaws.921187.

  4. Bates, D., Mächler, M., Bolker, B. and Walker, S. (2015). Fitting linear mixed-effects models using lme4. Journal of Statistical Software. 67(1): 1-48. https://doi.org/10.18637/jss.v067.i01.

  5. Bates, L.S. (1973). Rapid determination of free proline for water-stress studies. Plant Soil. 39: 205-207.

  6. Borromeo, I., Domenici, F., Giordani, C., Gallo, M.D. and Forni, C. (2024). Enhancing bean (Phaseolus vulgaris L.) resilience: Unveiling the role of halopriming against saltwater stress. Seeds. 3(2): 228-250. https://doi.org/10.3390/seeds3020018.

  7. Chaitanya, K.V., Krishna, C.R., Ramana, G.V. and Beebi, S.K. (2014). Salinity stress and sustainable agriculture-A review.  Agricultural Reviews. 35(1): 34-41. doi: 10.5958/j.0976-0741.35.1.004.

  8. Elsiddig, A.M.I., Zhou, G., Zhu, G., Nimir, N.E.A., Suliman, M.S.E., Ibrahim, M.E.H. and Ali, A.Y.A. (2023). Nitrogen fertilizer promoting salt tolerance of two sorghum varieties under different salt compositions. Chilean Journal of Agricultural Research. 83(1): 3-13. https://doi.org/10.4067/s0718- 58392023000100003.

  9. Emirzeoğlu, C. and Başak, H. (2020). Orta anadolu biber genotiplerinin farklı tuz konsantrasyonlarına tolerans düzeylerinin belirlenmesi. Uluslararası Tarım ve Yaban Hayatı Bilimleri Dergisi. 6(2): 129-140. https://doi.org/10.24180/ijaws. 689347.

  10. Farzana, S., Rasel, M., Tahjib Ul Arif, Md., Hossain, M.A., Azam, M.G., Galib, M.A.A., Mahamud, A.G.M.S.U. and Hossain, M.A. (2021). Salicylic acid and thiourea ameliorate the negative impact of salt stress in wheat (Triticum aestivum L.) seedlings by up-regulating photosynthetic pigments, leaf water status and antioxidant defense system. Journal of Phytology. 13: 130-145. https:// doi.org/10.25081/jp.2021.v13.7217.

  11. Fidan, E. and Ekincialp, A. (2017). Bazı fasulye (Phaseolus vulgaris L.) genotiplerinin farklı seviyelerdeki tuz stresine gösterdikleri tepkilerin incelenmesi. Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi. pp 558-568. https://doi.org/10.29 133/yyutbd.332012.

  12. Fidan, E. and Ekincialp, A. (2020). Effect of salt applications on plant growth in some pole and dwarf bean genotypes. Turkish Journal of Agriculture-Food Science and Technology. 8(5): 1074-1082. https://doi.org/10.24925/ turjaf.v8i5.1074-1082.3276.

  13. Fitzner, M., Schreiner, M. and Baldermann, S. (2023). The interaction of salinity and light regime modulates photosynthetic pigment content in edible halophytes in greenhouse and indoor farming. Frontiers in Plant Science. 14: 1105162. https://doi.org/10.3389/fpls.2023.1105162.

  14. Fu, H. and Yang, Y. (2023). How plants tolerate salt stress [Review of how plants tolerate salt stress]. Current Issues in Molecular Biology. 45(7): 5914-5934. Caister Academic Press. https://doi.org/10.3390/cimb45070374.

  15. Hasan, M.K., Nasiruddin, K.M., Al-Amin, M. and Hossain, A.K.M.S. (2016). In vitro screening of soybean genotypes under salinity stress. International Journal of Applied Sciences and Biotechnology. 4(2): 207-212. https://doi.org/ 10.3126/ijasbt.v4i2.15100.

  16. Karakaş, S., Dikilitaş, M. and Tıpırdamaz, R. (2019). Biochemical and molecular tolerance of Carpobrotus acinaciformis L. halophyte plants exposed to high level of NaCl stress. Harran Tarım ve Gıda Bilimleri Dergisi. 23(1): 99-107. https://doi.org/10.29050/harranziraat.464133.

  17. Kaymak, G. and Acar, Z. (2020). Orman üçgülü (Bituminaria bituminosa L.) genotiplerinin tuzluluğa dayanıklılık düzeylerinin belirlenmesi. Anadolu Journal of Agricultural Sciences. 35(1): 51-58. https://doi.org/10.7161/omuanajas. 608600.

  18. Kıpçak, S., Ekincialp, A., Erdinç, Ç., Kabay, T. and Şensoy, S. (2019). Tuz stresinin farklı fasulye genotiplerinde bazı besin elementi içeriği ile toplam antioksidan ve toplam fenol içeriğine etkisi. Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi. 29(1): 136. https://doi.org/10.29133/yyutbd.504748

  19. Kibar, B., Şahin, B. and Kiemde, O. (2020). Effects of different salt and putrescine applications on germination and seedling growth in bean (Phaseolus vulgaris L.). Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi. 10(4): 2315. https:// doi.org/10.21597/jist.776074.

  20. Kouki, S., L’taief, B., Al-Qthanin, R.N. and Sifi, B. (2021). Impacts of rhizobium strain Ar02 on the nodulation, growth, nitrogen (N2) fixation rate and ion accumulation in Phaseolus vulgaris L. under salt stress. Legume Research-An International Journal. 44(12): 1521-1528. doi: 10.18805/LRF-4716.

  21. Kumar, A., Sharma, A., Kaushik, S., Kundu, A., Dhansu, P., Verma, K., Kumar, R., Alsahli, A.A. and Sheoran, P. (2025). Temporal variations in morpho-physiology of sandalwood and gene expression analysis revealed shisham as host preference under water deficit and salinity stress. BMC Plant Biology. 25(1). https://doi.org/10.1186/s12870- 025-07333-9.

  22. Levitt, J. (1985). Responses of plants to environmental stresses. Journal of Range Management. 38(5): 480. https:// doi.org/10.2307/3899731.

  23. Mankar, G.D., Wayase, U.R., Shelke, D., Nikam, T.D. and Barmukh, R.B. (2021). Morphological, physiological and biochemical responses to NaCl-induced salt stress in mungbean (Vigna radiata L.) varieties. Notulae Scientia Biologicae. 13(2): 10936. https://doi.org/10.15835/nsb13210936.

  24. Mi, J., Ren, X., Shi, J., Wang, F., Wang, Q., Pang, H., Kang, L. and Wang, C. (2024). An insight into the different responses to salt stress in growth characteristics of two legume species during seedling growth. Frontiers in Plant Science. 14: 1342219. https://doi.org/10.3389/fpls.2023. 1342219.

  25. Mir, R.A., Logeshwari, T.R., Aryendu and Somasundaram, A. (2024). Elevated osmolytes accumulation helps in combating NaCl stress causing negative impacts on growth and metabolism of Vigna radiata (L.). Journal of Plant Stress Physiology. 10: 13-22. https://doi.org/10.25081/jpsp.2024.v10.8791.

  26. Priyadharshini, B., Vignesh, M., Prakash, M. and Anandan, R. (2019). Evaluation of black gram genotypes for saline tolerance at seedling stage. Indian Journal of Agricultural Research.  53(1): 83-87. doi: 10.18805/IJARe.A-5118.

  27. Temizgül, R. (2025). Soil salinization and ancient hulled wheat: A study on antioxidant defense mechanisms. Plants. 14(5): 678. https://doi.org/10.3390/plants14050678.

  28. Tuna, A.L. and Eroğlu, B. (2017). Tuz stresi altindaki biber (Capsicum annuum L.) bitkisinde bazi organik ve inorganik bileþiklerin antioksidatif sisteme etkileri. Anadolu Journal of Agricultural Sciences. 32(1): 121. https://doi.org/10.7161/omuanajas. 289038.

  29. Yavuzlar, E.E., Karadal, S. and Adak, N. (2021). In vitro koşullarda farklı glisin konsantrasyonlarının çileklerde tuzluluk stresi üzerine etkileri. Anadolu Journal of Agricultural Sciences. 36(2): 162-166. https://doi.org/10.7161/omuanajas.785167.

  30. Zhang, J., Meng, Q., Yang, Z., Zhang, Q., Yan, M., Hou, X. and Zhang, X. (2024). Humic acid promotes the growth of switchgrass under salt stress by ýmproving photosynthetic function. Agronomy. 14(5): 1079. https://doi.org/10.3390/ agronomy14051079.

  31. Zhou, H., Shi, H., Yang, Y., Feng, X., Chen, X., Xiao, F., Lin, H. and Guo, Y. (2023). Insights into plant salt stress signaling and tolerance [Review of insights into plant salt stress signaling and tolerance]. Journal of Genetics and Genomics/Journal of Genetics and Genomics. 51(1): 16. Elsevier BV. https://doi.org/10.1016/j.jgg.2023.08.007.

  32. Zhu, Y., Fu, Q., Zhu, C., Li, Y., Feng, Y., Su, X. and Fu, J. (2020). Review on physiological and molecular mechanisms for enhancing salt tolerance in turfgrass. Grass Research. 1. https://doi.org/10.48130/grares-0024-0020.

  33. Zong, J., Zhang, Z., Huang, P., Chen, N.Y., Xue, K.X., Tian, Z. and Yang, Y. (2021). Growth, physiological and photosynthetic responses of xanthoceras sorbifolium bunge seedlings under various degrees of salinity. Frontiers in Plant Science. 12: 730737. https://doi.org/10.3389/fpls. 2021. 730737.
Published In
Legume Research
Article Metrics
Metrics Icon
0
Views
0
Citations
Reviewed By
Share Article
Download Article
In this Article
    Contact us
    Follow us

    Full Research Article

    Evaluation of Salt Tolerance Mechanisms in Common Bean (Phaseolus vulgaris L.) Genotypes Exposed to Sodium Chloride and Sodium Sulfate: Morphological and Biochemical Perspectives

    Ş
    Şefik Tunahan Çengel1
    0009-0003-0336-6825
    B
    Barış Alaca2,*
    0000-0001-7542-6514
    S
    Sümeyye İslam1
    0009-0004-5821-2951
    G
    Gözde Hafize Yıldırım1
    0000-0002-0557-6442
    E
    Erkan Özata2
    0000-0002-4646-6426
    1Recep Tayyip Erdoğan University, Faculty of Agriculture, Department of Field Crops, Rize/Türkiye.
    2Black Sea Agricultural Research Institute, Field Crops Departments, Samsun, Türkiye.

    • Submitted22-01-2026|

    • Accepted23-02-2026|

    • First Online 10-03-2026|

    • doi 10.18805/LRF-933

    ABSTRACT

    Background: Common bean is a nutritionally important crop, but increasing soil salinity threatens seedling establishment and productivity.

    Methods: This greenhouse pot study compared early-stage morphological and biochemical responses of two common bean genotypes (G3 and G13) exposed to two salt types (NaCl and Na2SO4) at two concentrations (20 and 40 mM), alongside a non-saline control. Plant height, biomass traits, leaf area, SPAD chlorophyll index, photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophyll, carotenoids), chlorophyll a/b ratio and proline were assessed.

    Result: Salt treatments influenced SPAD and pigment-related traits, whereas effects on growth traits and proline were smaller or less consistent under the tested conditions. Genotype-dependent differences were observed across multiple traits. Overall, pigment traits may be useful for early-stage screening of salt responses under controlled conditions; however, conclusions should be interpreted cautiously given the limited genotype set.

    INTRODUCTION

    Global climate change, together with increasing drought and salinity stress, poses a serious threat to agricultural production (Kumar et al., 2025). Soil salinity, driven in part by inadequate irrigation and drainage, is expanding in many regions and remains a major soil-degradation problem limiting crop performance and yield (Yavuzlar et al., 2021). It is considered one of the most critical environmental constraints to plant growth, particularly in arid and semi-arid ecosystems (Temizgül, 2025).
           
    At the plant level, salinity suppresses photosynthesis, disrupts metabolic and enzymatic processes and induces oxidative stress, ultimately leading to growth and yield losses (Borromeo et al., 2024). These effects are reflected in measurable morphological, physiological and biochemical changes (Kıpçak et al., 2019). Plants respond through ion exclusion or vacuolar sequestration, osmotic adjustment and activation of antioxidant defense systems (Kumar et al., 2025; Zhang et al., 2024). Early developmental stages are particularly informative for detecting stress impacts within a short time frame (Zhu et al., 2020).
           
    Common bean (Phaseolus vulgaris L.) is an important food legume and improving its performance under salinity is relevant for both production stability and breeding. However, salinity studies frequently rely on NaCl alone, although field salinity may be chloride-or sulfate-dominated. Comparing NaCl and Na2SO4 can therefore provide a more accurate understanding of salt-tolerance mechanisms (Zhou et al., 2023). Linking salt type and intensity to measurable traits and integrating morphological and biochemical indicators strengthens screening approaches, while leaf structural and micromorphological descriptors may provide additional support. Trait-based screening can complement molecular marker and genome-editing strategies for developing stress-tolerant cultivars and enhancing food security (Fu and Yang, 2023; Priyadharshini et al., 2019; Kouki et al., 2021; Chaitanya et al., 2014).
           
    Few studies have compared chloride- and sulfate-dominated salinity at the early seedling stage using combined pigment profiling and multivariate integration. Therefore, this study compared early morphological and biochemical responses of two common bean genotypes under two concentrations of NaCl and Na2SO4. We hypothesized that (i) pigment traits would respond rapidly to increasing salinity and (ii) genotype-specific differences would be detectable in pigment and osmotic-adjustment traits under controlled greenhouse conditions.

    MATERIALS AND METHODS

    Plant material and experimental design
     
    The study was conducted in 2025 under greenhouse conditions at the Faculty of Agriculture, Recep Tayyip Erdoğan University, to evaluate the responses of two common bean candidate lines (Genotype 3 and Genotype 13) provided and coded by the national seed registration authority. Codes were retained for traceability and no salt-tolerant or -sensitive reference cultivars were included; thus, results reflect comparative responses under experimental conditions. Genotype 13 is bush-type with ~13 cm flat yellow pods, whereas Genotype 3 has white seeds (~8 mm) and high adaptability.
           
    Treatments included: control, NaCl 20 mM (1.75 g/2 L) and 40 mM (3.51 g/2 L) and Na2SO4 20 mM (4.26 g/2 L) and 40 mM (8.52 g/2 L). Plants were grown in 2-L pots filled with sterile peat (pH 6.0; 1.0 g L-1 fertilizer), with five seedlings per pot. The experiment followed a 2 (genotype) × 5 (salt) factorial design with three replications; three pots per combination were used and the pot was considered the experimental unit (Fig 1). Salt solutions were applied once at 10 DAS after a 1-day irrigation pause and respective solutions were maintained for 30 days (controls received water). Measurements were taken 30 days after treatment. Data were averaged at the pot level to avoid pseudo-replication. Measured traits included plant height, SPAD, green/dry weight, leaf area, chlorophyll a and b, total chlorophyll, total carotenoids, chlorophyll a/b ratio and proline.

    Fig 1: Greenhouse experimental setup showing common bean (Phaseolus vulgaris L.) plants subjected to five salinity treatments (Control, NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM).


     
    Biochemical analysis
     
    Photosynthetic pigments (total chlorophyll, chlorophyll a and b and total carotenoids) were quantified spectrophotometrically using the Arnon method (Arnon, 1949) and proline (µmol g-1 FW) was determined following Bates (1973) using the acid-ninhydrin assay with toluene extraction and a standard curve at 520 nm (Fig 2-3).

    Fig 2: Overview of the laboratory procedures used for chlorophyll and carotenoid extraction in common bean leaves.



    Fig 3: Laboratory workflow for proline determination in common bean leaves.


     
    Statistical analysis
     
    Statistical analyses were performed in R (lme4; Bates et al., 2015) using a two-factor mixed model with genotype, salt treatment and their interaction as fixed effects and replication as a random effect (pot = experimental unit); significant effects (p<0.05) were followed by Tukey’s HSD for mean separation.

    RESULTS AND DISCUSSION

    Correlation analysis showed strong positive relationships among pigment-related traits (Fig 4). Total chlorophyll was strongly correlated with chlorophyll a (r>0.90, p<0.001), chlorophyll b (r>0.95, p<0.001) and total carotenoids (r = 0.98, p<0.001). Chlorophyll a and chlorophyll b were also positively correlated.

    Fig 4: Correlation matrix illustrating pairwise relationships among morphological, physiological and biochemical traits of common bean plants exposed to different salinity treatments.


           
    Proline showed positive correlations with green weight (r = 0.40) and leaf area (r = 0.66, p<0.05). Correlations between proline and chlorophyll-related parameters were weak (r<0.20). Plant height showed low negative correlations with other traits (ranging from -0.05 to -0.30). Leaf area and chlorophyll (SPAD) values were positively correlated (p<0.01).
     
    Principal component analysis (PCA)
     
    PCA separated treatments along PC1–PC2 based on combined morphological and biochemical variation (Fig 5). Growth/biomass traits loaded mainly on one axis, whereas pigment/biochemical variables loaded on the other. Pigment vectors were long and similarly oriented, while proline pointed in a distinct direction. Controls clustered near pigment variables; Na2SO4 40 mM separated and aligned with biomass traits and proline. NaCl and Na2SO4 treatments diverged and Na2SO4 20 mM was close to NaCl 40 mM in associations with leaf area and growth traits.

    Fig 5: Principal component biplot (PC1 vs. PC2) illustrating the multivariate response of common bean plants to five salinity treatments: Control (0 mM), NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM.


     
    Pigment traits
     
    Pigment traits differed among treatments (Fig 6; Table 2-3): controls showed the highest values and reductions increased with salinity, particularly at 40 mM. The chlorophyll a/b ratio varied, with higher values under some salt treatments (notably Na2SO4 40 mM). Low-salt treatments occasionally matched or slightly exceeded control values, but both salts at 40 mM reduced pigments overall.

    Fig 6: Tukey HSD compact letter display (CLD) for six pigment-related traits of common bean plants subjected to five salt treatments: Control (0 mM), NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM.


     
    Hierarchical clustering
     
    Clustering grouped treatments into high-salt (Na2SO4 40 mM, NaCl 40 mM) vs control/low-salt (control, Na2 SO4 20 mM, NaCl 20 mM) clusters (Fig 7). Na2SO4 40 mM showed lower dry weight, green weight and SPAD with higher proline; NaCl 40 mM showed the lowest pigment traits. Pigments clustered together, whereas proline formed a separate cluster. Genotypes separated (Fig 8): G3 had higher pigments, proline and green/dry weight, while plant height was not higher; G13 showed lower values.

    Fig 7: Z-score normalized hierarchical clustered heatmap of mean trait values across five salinity treatments: Control (0 mM), NaCl 20 mM, NaCl 40 mM, Na2SO4 20 mM and Na2SO4 40 mM.



    Fig 8: Z-score normalized hierarchical clustered heatmap comparing the physiological, biochemical and pigment-related traits of genotypes G3 and G13.


     
    Agronomic traits
     
    Plant height was not affected by treatments (p = 0.886; 35.35-39.97 cm) (Table 1). SPAD was significantly influenced (p = 0.002), with the highest value at 40 mM Na2 SO4 (34.45) and the lowest at 20 mM NaCl (28.32). Green weight did not differ among treatments (p = 0.435; 0.38-0.47 g). Genotype effects were significant for plant height (p = 0.001) and green weight (p = 0.005) (Table 1).

    Table 1: Significance levels for plant height, chlorophyll (SPAD) and green weight in bean genotypes under different salt-stress treatments.


           
    Dry weight was not treatment-significant (p = 0.603; 0.06-0.12 g; highest at 40 mM Na2SO4) (Table 2). Leaf area was not affected by treatments (p = 0.131; 20.50-27.79 cm²), but genotype effects were significant (p = 0.002).

    Table 2: Significance levels for dry weight, leaf area and chlorophyll a in bean genotypes under different salt-stress treatments.


           
    Pigment traits (Table 2-3) generally declined at higher salinity; chlorophyll a was relatively higher at 20 mM NaCl (Table 2), whereas chlorophyll b was lower at 20 mM Na2SO4 and 40 mM NaCl (Table 3). Total chlorophyll and carotenoids decreased at higher salt levels. Proline did not differ among treatments (Table 4), but genotype effects were significant for pigments and proline (Table 2-4).

    Table 3: Significance levels for chlorophyll b, total carotenoids and total chlorophyll in bean genotypes under different salt-stress treatments.



    Table 4: Significance levels for chlorophyll a/b ratio and proline in bean genotypes under different salt-stress treatments.


           
    Multivariate analyses indicate that salt stress modifies common bean performance through coordinated shifts in photosynthetic pigments and more variable responses in growth and osmotic traits. This pattern supports the view that salinity acts through partially independent physiological pathways, with photosynthesis, biomass accumulation and osmotic adjustment differing according to salt type, stress intensity and genotype (Hasan et al., 2016; Zhu et al., 2020; Mir et al., 2024).
           
    The correlation matrix (Fig 4) showed strong clustering among pigment traits, with total chlorophyll strongly and positively associated with chlorophyll a, chlorophyll b and total carotenoids. This suggests that the pigment system functions as an integrated unit under salinity, consistent with the protective roles of chlorophylls and carotenoids in maintaining photosystem integrity (Mir et al., 2024). Previous studies report greater sensitivity of chlorophyll a and overall chlorophyll decline under increasing salinity (Aşcı et al., 2021; Kibar et al., 2020) and the present results indicate that pigment reductions occur in a coordinated rather than isolated manner.
           
    Proline related positively to green weight and leaf area but weakly to pigment traits, indicating its accumulation isn’t merely due to pigment decline and may be controlled by different pathways affected by genotype and stress duration. (Mir et al., 2024). The linkage between leaf area and chlorophyll status, as well as the positive association between leaf area and SPAD values, supports coordinated variation in leaf development and chlorophyll density under stress (Zhang et al., 2024). Compensatory physiological adjustments may partly explain why morphological correlations were weaker than pigment correlations (Karakaş et al., 2019).
           
    PCA (Fig 5) showed treatment responses driven by stress intensity and salt type. Separation along growth/biomass and pigment/biochemical axes indicates salinity disrupts photosynthesis and prompts adaptive changes. (Hasan et al., 2016; Zhu et al., 2020). The control group’s proximity to pigment vectors reflects expected pigment decline under salinity (Zhang et al., 2024; Aşcı et al., 2021). Divergence between NaCl and Na2SO4 indicates partially distinct metabolic reorganization pathways (Levitt, 1985). The proximity of 20 mM Na2SO4 and 40 mM NaCl in certain morphological associations suggests that once stress thresholds are exceeded, different salts may impose comparable growth constraints while operating through different biochemical routes (Mi et al., 2024).
           
    Na2SO4 (40 mM) aligned with proline and biomass variables, indicating disrupted homeostasis and potential water and nutrient uptake limitations. (Farzana et al., 2021). In contrast, stronger pigment depletion under NaCl is consistent with higher photo-oxidative pressure and direct effects on chlorophyll stability (Zhang et al., 2024; Aşcı et al., 2021). The synchronized pigment vectors versus the proline direction support independent regulation of osmotic adjustment and pigment maintenance. (Mir et al., 2024).
           
    Controls showed the highest pigment values, while high salinity significantly reduced them, confirming chlorophylls and carotenoids are highly responsive to salt stress. (Mir et al., 2024; Zong et al., 2021). More pronounced NaCl losses align with inhibited chlorophyll synthesis and faster pigment degradation. (Zhang et al., 2024; Emirzeoğlu and Başak, 2020). Shifts in the chlorophyll a/b ratio suggest stress-driven restructuring of light-harvesting complexes (Kaymak and Acar, 2020; Tuna and Eroğlu, 2017; Elsiddig et al., 2023). Slight low-salinity increases may indicate hormesis (Mankar et al., 2021), while higher concentrations harm pigment biosynthesis and photosystem II stability. (Fitzner et al., 2023; Zhang et al., 2024). Thus, pigment traits are particularly informative for early screening, although multiple pigment parameters should be integrated for robust evaluation (Mi et al., 2024).
           
    Hierarchical clustering (Fig 7) separated high- from low-salt treatments, highlighting concentration as the dominant driver (Fidan and Ekincialp, 2017). Within the high-salt cluster, Na2SO4 (40 mM) showed lower biomass and SPAD but higher proline, while NaCl (40 mM) caused stronger pigment suppression, indicating different stress signatures of sulfate-and chloride-based salinity. (Elsiddig et al., 2023; Farzana et al., 2021; Mir et al., 2024). Similar growth reductions under salinity have been widely reported (Fidan and Ekincialp, 2020; Kibar et al., 2020; Temizgül, 2025).
           
    Although genotype-dependent responses to salinity are documented (Aini et al., 2014), this study included only two genotypes; findings should be seen as genotype-specific, not generalizable. Differences in pigment and biomass traits indicate genetic background influences photosynthetic stability and biomass partitioning under salt stress. Because salt tolerance is polyfactorial, integrating morphological and biochemical traits is essential, but broader conclusions need validation with more genotypes sets (Mi et al., 2024).

    CONCLUSION

    Under greenhouse pot conditions, salt treatments primarily influenced pigment-related traits and the SPAD index, indicating early sensitivity of the photosynthetic apparatus to both NaCl- and Na2SO4-dominated salinity. Growth traits showed smaller or less consistent treatment effects, while genotype differences were evident across multiple traits. Proline responses were genotype-dependent and did not present a consistent treatment-driven pattern under the exposure conditions used. Because only two genotypes were evaluated and the experiment was conducted under controlled greenhouse conditions, broader breeding conclusions should be interpreted cautiously. Future work should validate screening traits using larger genotype panels and sustained salinity regimes across environments.

    ACKNOWLEDGEMENT

    Authors declare that no funds, grants, or other support were received during the preparation of this manuscript.
     
    Disclaimers
     
    The views and conclusions expressed in this article are solely those of the authors and do not necessarily represent the views of their affiliated institutions. The authors are responsible for the accuracy and completeness of the information provided, but do not accept any liability for any direct or indirect losses resulting from the use of this content.

    CONFLICT OF INTEREST

    The authors declare that there are no conflicts of interest regarding the publication of this article. No funding or sponsorship influenced the design of the study, data collection, analysis, decision to publish, or preparation of the manuscript.

    REFERENCES


    1. Aini, N., Syekhfani, S., Yamika, W.S.D., Purwaningrahayu, R.D. and Setiawan, A. (2014). Growth and physiological characteristics of soybean genotypes (Glycine max L.) toward salinity stress. Agrivita Journal of Agricultural Science. 36(3): 201-209. https://doi.org/10.17503/ agrivita-2014-36-3-201-209.

    2. Arnon, D.I. (1949). Copper enzymes in isolated chloroplasts, polyphenoxidase in Beta vulgaris. Plant Physiol. 24: 1-15.

    3. Aşcı, Ö.Ö., Saral, M.A. and Arıcı, Y.K. (2021). Tuz stresinin börülcede bazı fizyolojik özellikler ve mineral madde oranlarına etkisi. Uluslararası Tarım ve Yaban Hayatı Bilimleri Dergisi. 7(2): 297-305. https://doi.org/10.24180/ ijaws.921187.

    4. Bates, D., Mächler, M., Bolker, B. and Walker, S. (2015). Fitting linear mixed-effects models using lme4. Journal of Statistical Software. 67(1): 1-48. https://doi.org/10.18637/jss.v067.i01.

    5. Bates, L.S. (1973). Rapid determination of free proline for water-stress studies. Plant Soil. 39: 205-207.

    6. Borromeo, I., Domenici, F., Giordani, C., Gallo, M.D. and Forni, C. (2024). Enhancing bean (Phaseolus vulgaris L.) resilience: Unveiling the role of halopriming against saltwater stress. Seeds. 3(2): 228-250. https://doi.org/10.3390/seeds3020018.

    7. Chaitanya, K.V., Krishna, C.R., Ramana, G.V. and Beebi, S.K. (2014). Salinity stress and sustainable agriculture-A review.  Agricultural Reviews. 35(1): 34-41. doi: 10.5958/j.0976-0741.35.1.004.

    8. Elsiddig, A.M.I., Zhou, G., Zhu, G., Nimir, N.E.A., Suliman, M.S.E., Ibrahim, M.E.H. and Ali, A.Y.A. (2023). Nitrogen fertilizer promoting salt tolerance of two sorghum varieties under different salt compositions. Chilean Journal of Agricultural Research. 83(1): 3-13. https://doi.org/10.4067/s0718- 58392023000100003.

    9. Emirzeoğlu, C. and Başak, H. (2020). Orta anadolu biber genotiplerinin farklı tuz konsantrasyonlarına tolerans düzeylerinin belirlenmesi. Uluslararası Tarım ve Yaban Hayatı Bilimleri Dergisi. 6(2): 129-140. https://doi.org/10.24180/ijaws. 689347.

    10. Farzana, S., Rasel, M., Tahjib Ul Arif, Md., Hossain, M.A., Azam, M.G., Galib, M.A.A., Mahamud, A.G.M.S.U. and Hossain, M.A. (2021). Salicylic acid and thiourea ameliorate the negative impact of salt stress in wheat (Triticum aestivum L.) seedlings by up-regulating photosynthetic pigments, leaf water status and antioxidant defense system. Journal of Phytology. 13: 130-145. https:// doi.org/10.25081/jp.2021.v13.7217.

    11. Fidan, E. and Ekincialp, A. (2017). Bazı fasulye (Phaseolus vulgaris L.) genotiplerinin farklı seviyelerdeki tuz stresine gösterdikleri tepkilerin incelenmesi. Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi. pp 558-568. https://doi.org/10.29 133/yyutbd.332012.

    12. Fidan, E. and Ekincialp, A. (2020). Effect of salt applications on plant growth in some pole and dwarf bean genotypes. Turkish Journal of Agriculture-Food Science and Technology. 8(5): 1074-1082. https://doi.org/10.24925/ turjaf.v8i5.1074-1082.3276.

    13. Fitzner, M., Schreiner, M. and Baldermann, S. (2023). The interaction of salinity and light regime modulates photosynthetic pigment content in edible halophytes in greenhouse and indoor farming. Frontiers in Plant Science. 14: 1105162. https://doi.org/10.3389/fpls.2023.1105162.

    14. Fu, H. and Yang, Y. (2023). How plants tolerate salt stress [Review of how plants tolerate salt stress]. Current Issues in Molecular Biology. 45(7): 5914-5934. Caister Academic Press. https://doi.org/10.3390/cimb45070374.

    15. Hasan, M.K., Nasiruddin, K.M., Al-Amin, M. and Hossain, A.K.M.S. (2016). In vitro screening of soybean genotypes under salinity stress. International Journal of Applied Sciences and Biotechnology. 4(2): 207-212. https://doi.org/ 10.3126/ijasbt.v4i2.15100.

    16. Karakaş, S., Dikilitaş, M. and Tıpırdamaz, R. (2019). Biochemical and molecular tolerance of Carpobrotus acinaciformis L. halophyte plants exposed to high level of NaCl stress. Harran Tarım ve Gıda Bilimleri Dergisi. 23(1): 99-107. https://doi.org/10.29050/harranziraat.464133.

    17. Kaymak, G. and Acar, Z. (2020). Orman üçgülü (Bituminaria bituminosa L.) genotiplerinin tuzluluğa dayanıklılık düzeylerinin belirlenmesi. Anadolu Journal of Agricultural Sciences. 35(1): 51-58. https://doi.org/10.7161/omuanajas. 608600.

    18. Kıpçak, S., Ekincialp, A., Erdinç, Ç., Kabay, T. and Şensoy, S. (2019). Tuz stresinin farklı fasulye genotiplerinde bazı besin elementi içeriği ile toplam antioksidan ve toplam fenol içeriğine etkisi. Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi. 29(1): 136. https://doi.org/10.29133/yyutbd.504748

    19. Kibar, B., Şahin, B. and Kiemde, O. (2020). Effects of different salt and putrescine applications on germination and seedling growth in bean (Phaseolus vulgaris L.). Iğdır Üniversitesi Fen Bilimleri Enstitüsü Dergisi. 10(4): 2315. https:// doi.org/10.21597/jist.776074.

    20. Kouki, S., L’taief, B., Al-Qthanin, R.N. and Sifi, B. (2021). Impacts of rhizobium strain Ar02 on the nodulation, growth, nitrogen (N2) fixation rate and ion accumulation in Phaseolus vulgaris L. under salt stress. Legume Research-An International Journal. 44(12): 1521-1528. doi: 10.18805/LRF-4716.

    21. Kumar, A., Sharma, A., Kaushik, S., Kundu, A., Dhansu, P., Verma, K., Kumar, R., Alsahli, A.A. and Sheoran, P. (2025). Temporal variations in morpho-physiology of sandalwood and gene expression analysis revealed shisham as host preference under water deficit and salinity stress. BMC Plant Biology. 25(1). https://doi.org/10.1186/s12870- 025-07333-9.

    22. Levitt, J. (1985). Responses of plants to environmental stresses. Journal of Range Management. 38(5): 480. https:// doi.org/10.2307/3899731.

    23. Mankar, G.D., Wayase, U.R., Shelke, D., Nikam, T.D. and Barmukh, R.B. (2021). Morphological, physiological and biochemical responses to NaCl-induced salt stress in mungbean (Vigna radiata L.) varieties. Notulae Scientia Biologicae. 13(2): 10936. https://doi.org/10.15835/nsb13210936.

    24. Mi, J., Ren, X., Shi, J., Wang, F., Wang, Q., Pang, H., Kang, L. and Wang, C. (2024). An insight into the different responses to salt stress in growth characteristics of two legume species during seedling growth. Frontiers in Plant Science. 14: 1342219. https://doi.org/10.3389/fpls.2023. 1342219.

    25. Mir, R.A., Logeshwari, T.R., Aryendu and Somasundaram, A. (2024). Elevated osmolytes accumulation helps in combating NaCl stress causing negative impacts on growth and metabolism of Vigna radiata (L.). Journal of Plant Stress Physiology. 10: 13-22. https://doi.org/10.25081/jpsp.2024.v10.8791.

    26. Priyadharshini, B., Vignesh, M., Prakash, M. and Anandan, R. (2019). Evaluation of black gram genotypes for saline tolerance at seedling stage. Indian Journal of Agricultural Research.  53(1): 83-87. doi: 10.18805/IJARe.A-5118.

    27. Temizgül, R. (2025). Soil salinization and ancient hulled wheat: A study on antioxidant defense mechanisms. Plants. 14(5): 678. https://doi.org/10.3390/plants14050678.

    28. Tuna, A.L. and Eroğlu, B. (2017). Tuz stresi altindaki biber (Capsicum annuum L.) bitkisinde bazi organik ve inorganik bileþiklerin antioksidatif sisteme etkileri. Anadolu Journal of Agricultural Sciences. 32(1): 121. https://doi.org/10.7161/omuanajas. 289038.

    29. Yavuzlar, E.E., Karadal, S. and Adak, N. (2021). In vitro koşullarda farklı glisin konsantrasyonlarının çileklerde tuzluluk stresi üzerine etkileri. Anadolu Journal of Agricultural Sciences. 36(2): 162-166. https://doi.org/10.7161/omuanajas.785167.

    30. Zhang, J., Meng, Q., Yang, Z., Zhang, Q., Yan, M., Hou, X. and Zhang, X. (2024). Humic acid promotes the growth of switchgrass under salt stress by ýmproving photosynthetic function. Agronomy. 14(5): 1079. https://doi.org/10.3390/ agronomy14051079.

    31. Zhou, H., Shi, H., Yang, Y., Feng, X., Chen, X., Xiao, F., Lin, H. and Guo, Y. (2023). Insights into plant salt stress signaling and tolerance [Review of insights into plant salt stress signaling and tolerance]. Journal of Genetics and Genomics/Journal of Genetics and Genomics. 51(1): 16. Elsevier BV. https://doi.org/10.1016/j.jgg.2023.08.007.

    32. Zhu, Y., Fu, Q., Zhu, C., Li, Y., Feng, Y., Su, X. and Fu, J. (2020). Review on physiological and molecular mechanisms for enhancing salt tolerance in turfgrass. Grass Research. 1. https://doi.org/10.48130/grares-0024-0020.

    33. Zong, J., Zhang, Z., Huang, P., Chen, N.Y., Xue, K.X., Tian, Z. and Yang, Y. (2021). Growth, physiological and photosynthetic responses of xanthoceras sorbifolium bunge seedlings under various degrees of salinity. Frontiers in Plant Science. 12: 730737. https://doi.org/10.3389/fpls. 2021. 730737.
    In this Article
      Contact us
      Follow us
      Published In
      Legume Research

      Editorial Board

      View all (0)