INTRODUCTION: Selenium (Se) deficiency, stemming from malnutrition in humans and animals, has the potential to disrupt many vital physiological processes, particularly those reliant on specific selenoproteins. Agronomic biofortification of crops through the application of Se-containing sprays provides an efficient method to enhance the Se content in the harvested biomass. An optimal candidate for systematic enrichment, guaranteeing a broad trophic impact, must meet several criteria: (i) efficient accumulation of Se without compromising crop yield, (ii) effective conversion of mineral Se fertilizer into usable organically bound Se forms (Seorg), (iii) acceptance of a Se-enriched crop as livestock feed, and (iv), interest from the food processing industry in utilization of Se-enriched outputs. Hence, priority should be given to high-protein leafy crops, such as soybean. METHODS: A three-year study in the Czech Republic was conducted to investigate the response of field-grown soybean plants to foliar application of Na2SeO4 solutions (0, 15, 40, and 100 g/ha Se); measured outcomes included crop yield, Se distribution in aboveground biomass, and the chemical speciation of Se in seeds. RESULTS AND DISCUSSION: Seed yield was unaffected by applied SeO4 2-, with Se content reaching levels as high as 16.2 mg/kg. The relationship between SeO4 2-dose and Se content in seeds followed a linear regression model. Notably, the soybeans demonstrated an impressive 73% average recovery of Se in seeds. Selenomethionine was identified as the predominant species of Se in enzymatic hydrolysates of soybean, constituting up to 95% of Seorg in seeds. Minor Se species, such as selenocystine, selenite, and selenate, were also detected. The timing of Se spraying influenced both plant SeO4 2- biotransformation and total content in seeds, emphasizing the critical importance of optimizing the biofortification protocol. Future research should explore the economic viability, long-term ecological sustainability, and the broad nutritional implications of incorporating Se-enriched soybeans into food for humans and animals.

Department of Agroenvironmental Chemistry and Plant Nutrition Czech University of Life Sciences Prague Prague Czechia

See more in PubMed

Astaneh R. K., Bolandnazar S., Nahandi F. Z., Oustan S. (2019). Effects of selenium on enzymatic changes and productivity of garlic under salinity stress. S. Afr. J. Bot. 121, 447–455. doi: 10.1016/j.sajb.2018.10.037 DOI

Broadley M. R., Alcock J., Alford J., Cartwright P., Foot I., Fairweather-Tait S. J., et al. . (2010). Selenium biofortification of high-yielding winter wheat (Triticum aestivum L.) by liquid or granular Se fertilisation. Plant Soil 332, 5–18. doi: 10.1007/s11104-009-0234-4 DOI

Broadley M. R., White P. J., Bryson R. J., Meacham M. C., Bowen H. C., Johnson S. E., et al. . (2006). Biofortification of UK food crops with selenium. Proc. Nutr. Soc 65, 169–181. doi: 10.1079/PNS2006490 PubMed DOI

Dai H., Wei S., Twardowska I. (2020). Biofortification of soybean (Glycine max L.) with Se and Zn, and enhancing its physiological functions by spiking these elements to soil during flowering phase. Sci. Total Environ. 740, 139648. doi: 10.1016/j.scitotenv.2020.139648 PubMed DOI

Deliboran A. (2023). Selenium biofortification of grain maize through foliar application of sodium selenate: selenium accumulation and recovery by the grain. Commun. Soil Sci. Plant Anal. 54, 1564–1581. doi: 10.1080/00103624.2023.2177304 DOI

Deng X., Liu K., Li M., Zhang W., Zhao X., Zhao Z., et al. . (2017). Difference of selenium uptake and distribution in the plant and selenium form in the grains of rice with foliar spray of selenite or selenate at different stages. Field Crops Res. 211, 165–171. doi: 10.1016/j.fcr.2017.06.008 DOI

Di X., Qin X., Zhao L., Liang X., Xu Y., Sun Y., et al. . (2023). Selenium distribution, translocation and speciation in wheat (Triticum aestivum L.) after foliar spraying selenite and selenate. Food Chem. 400, 134077. doi: 10.1016/j.foodchem.2022.134077 PubMed DOI

Ducsay L., Ložek O., Marček M., Varényiová M., Hozlár P., Lošák T. (2016). Possibility of selenium biofortification of winter wheat grain. Plant Soil Environ. 62, 379–383. doi: 10.17221/324/2016-PSE DOI

Galinha C., Sánchez-Martínez M., Pacheco A. M. G., Freitas M do C., Coutinho J., Maçãs B., et al. . (2014). Characterization of selenium-enriched wheat by agronomic biofortification. J. Food Sci. Technol. 52, 4236–4245. doi: 10.1007/s13197-014-1503-7 PubMed DOI PMC

Hossain A., Skalicky M., Brestic M., Maitra S., Sarkar S., Ahmad Z., et al. . (2021). Selenium biofortification: roles, mechanisms, responses and prospects. Molecules 26, 881. doi: 10.3390/molecules26040881 PubMed DOI PMC

Jiang Y., El Mehdawi A. F., Tripti A. F., Lima L. W., Stonehouse G., Fakra S. C., et al. . (2018). Characterization of selenium accumulation, localization and speciation in buckwheat–implications for biofortification. Front. Plant Sci. 9. doi: 10.3389/fpls.2018.01583 PubMed DOI PMC

Lidon F. C., Oliveira K., Galhano C., Guerra M., Ribeiro M. M., Pelica J., et al. . (2019). Selenium biofortification of rice through foliar application with selenite and selenate. Exp. Agric. 55, 528–542. doi: 10.1017/S0014479718000157 DOI

Lyons G. (2010). Selenium in cereals: Improving the efficiency of agronomic biofortification in the UK. Plant Soil. 332, 1–4. doi: 10.1007/s11104-010-0282-9 DOI

Meenakshi J. V., Johnson N. L., Manyong V. M., De Groote H., Javelosa J., Yanggen D. R., et al. . (2010). How cost-effective is biofortification in combating micronutrient malnutrition? An ex ante assessment. World Dev. 38, 64–75. doi: 10.1016/j.worlddev.2009.03.014 DOI

Mrština T., Praus L., Kaplan L., Száková J., Tlustoš P. (2022). Efficiency of selenium biofortification of spring wheat: the role of soil properties and organic matter amendment. Plant Soil Environ. 68, 572–579. doi: 10.17221/357/2022-PSE DOI

Nawaz F., Ashraf M. Y., Ahmad R., Waraich E. A., Shabbir R. N., Bukhari M. A. (2015). Supplemental selenium improves wheat grain yield and quality through alterations in biochemical processes under normal and water deficit conditions. Food Chem. 175, 350–357. doi: 10.1016/j.foodchem.2014.11.147 PubMed DOI

Ngigi P. B., Lachat C., Masinde P. W., Du Laing G. (2019). Agronomic biofortification of maize and beans in Kenya through selenium fertilization. Environ. Geochem. Health 41, 2577–2591. doi: 10.1007/s10653-019-00309-3 PubMed DOI

Niedzielski P., Rudnicka M., Wachelka M., Kozak L., Rzany M., Wozniak M., et al. . (2016). Selenium species in selenium fortified dietary supplements. Food Chem. 190, 454–459. doi: 10.1016/j.foodchem.2015.05.125 PubMed DOI

Poblaciones M. J., Rodrigo S. M., Santamaría O. (2013). Evaluation of the potential of peas (Pisum sativum L.) to be used in selenium biofortification programs under mediterranean conditions. Biol. Trace Elem. Res. 151, 132–137. doi: 10.1007/s12011-012-9539-x PubMed DOI

Poblaciones M. J., Rodrigo S., Santamaria O., Chen Y., Mcgrath S. P. (2014. a). Selenium accumulation and speciation in biofortified chickpea (Cicer arietinum L.) under Mediterranean conditions. J. Sci. Food Agric. 94, 1101–1106. doi: 10.1002/jsfa.6372 PubMed DOI

Poblaciones M. J., Rodrigo S., Santamaría O., Chen Y., McGrath S. P. (2014. b). Agronomic selenium biofortification in Triticum durum under Mediterranean conditions: From grain to cooked pasta. Food Chem. 146, 378–384. doi: 10.1016/j.foodchem.2013.09.070 PubMed DOI

Praus L., Száková J., Steiner O., Goessler W. (2019). Rapeseed (Brassica napus L.) biofortification with selenium: How do sulphate and phosphate influence the efficiency of selenate application into soil? Arch. Agron. Soil Sci. 65, 2059–2072. doi: 10.1080/03650340.2019.1592163 DOI

Rahman M. M., Erskine W., Materne M. A., McMurray L. M., Thavarajah P., Thavarajah D., et al. . (2015). Enhancing selenium concentration in lentil (Lens culinaris subsp. culinaris) through foliar application. J. Agric. Sci. 153, 656–665. doi: 10.1017/S0021859614000495 DOI

Rayman M. P. (2012). Selenium and human health. Lancet 379, 1256–1268. doi: 10.1016/S0140-6736(11)61452-9 PubMed DOI

Sarwar N., Akhtar M., Kamran M. A., Imran M., Riaz M. A., Kamran K., et al. . (2020). Selenium biofortification in food crops: Key mechanisms and future perspectives. J. Food Compos. Anal. 93, 103615. doi: 10.1016/j.jfca.2020.103615 DOI

Schiavon M., Nardi S., dalla Vecchia F., Ertani A. (2020). Selenium biofortification in the 21st century: status and challenges for healthy human nutrition. Plant Soil. 453, 245–270. doi: 10.1007/s11104-020-04635-9 PubMed DOI PMC

Schiavon M., Vecchia F. D. (2017). “Selenium and Algae: Accumulation, Tolerance Mechanisms and Dietary Perspectives,” in Selenium in plants. Plant Ecophysiology, vol. 11 . Eds. Pilon-Smits E. A. H., Winkel L. H. E., Lin Z. Q. (Springer, Cham: ), 69–77.

Silva M. A., de Sousa G. F., Bañuelos G., Amaral D., Brown P. H., Guilherme L. R. G. (2023). Selenium speciation in se-enriched soybean grains from biofortified plants grown under different methods of selenium application. Foods 12, 1214. doi: 10.3390/foods12061214 PubMed DOI PMC

Sors T. G., Ellis D. R., Salt D. E. (2005). Selenium uptake, translocation, assimilation and metabolic fate in plants. Photosynth. Res. 86, 373–389. doi: 10.1007/s11120-005-5222-9 PubMed DOI

Terry N., Zayed A. M., De Souza M. P., Tarun A. S. (2000). SELENIUM IN HIGHER PLANTS. Annu. Rev. Plant Biol. 51, 401–432. doi: 10.1146/annurev.arplant.51.1.401 PubMed DOI

Wang M., Ali F., Wang M., Dinh Q. T., Zhou F., Bañuelos G. S., et al. . (2020). Understanding boosting selenium accumulation in Wheat (Triticum aestivum L.) following foliar selenium application at different stages, forms, and doses. Environ. Sci. pollut. Res. 27, 717–728. doi: 10.1007/s11356-019-06914-0 PubMed DOI

Wang P., Lombi E., Zhao F. J., Kopittke P. M. (2016). Nanotechnology: A new opportunity in plant sciences. Trends Plant Sci. 21, 699–712. doi: 10.1016/j.tplants.2016.04.005 PubMed DOI

Wang M., Zhou F., Cheng N., Chen P., Ma Y., Zhai H., et al. . (2022). Soil and foliar selenium application: Impact on accumulation, speciation, and bioaccessibility of selenium in wheat (Triticum aestivum L.). Front. Plant Sci. 13. doi: 10.3389/fpls.2022.988627 PubMed DOI PMC

Yang F., Chen L., Hu Q., Pan G. (2003). Effect of the application of selenium on selenium content of soybean and its products. Biol. Trace Elem. Res. 93, 249–256. doi: 10.1385/BTER:93:1-3:249 PubMed DOI

Yildiztugay E., Ozfidan-Konakci C., Kucukoduk M., Tekis S. A. (2017). The impact of selenium application on enzymatic and non-enzymatic antioxidant systems in Zea mays roots treated with combined osmotic and heat stress. Arch. Agron. Soil Sci. 63, 261–275. doi: 10.1080/03650340.2016.1201810 DOI

Zhang X., He H., Xiang J., Yin H., Hou T. (2020). Selenium-containing proteins/peptides from plants: A review on the structures and functions. J. Agric. Food Chem. 68, 15061–15073. doi: 10.1021/acs.jafc.0c05594 PubMed DOI

Zhang H., Zhao Z., Zhang X., Zhang W., Huang L., Zhang Z., et al. . (2019). Effects of foliar application of selenate and selenite at different growth stages on Selenium accumulation and speciation in potato (Solanum tuberosum L.). Food Chem. 286, 550–556. doi: 10.1016/j.foodchem.2019.01.185 PubMed DOI