Substrate-fertilizer-integrated agarose-based hydrogel as a growth substrate for selenium-enriched cultivation of mature pakchoi (Brassica chinensis L.)

Different agarose-based (agar-based) hydrogels for Se-enriched cultures of mature vegetables were successfully synthesized, and their structure and morphology were characterized using FT-IR, XRD, TGA, and SEM. The growth indices and Se content of pakchoi plants grown on different agar-based hydrogels were measured. The results showed that the Agar-NS-SeCA-AC hydrogel system can support plant growth for prolonged periods under Se-enriched cultivation. The introduction of the three additives accounted for a 191.09 % increase in the pakchoi yield compared with that of the pristine Agar hydrogel but improved the Se content of the pakchoi by 10.77 %. Moreover, an orthogonal experimental design was used to analyze the influence of NS, SeCA, and AC on the growth and Se enrichment effect of pakchoi grown on agar-based hydrogels. Our findings provide a novel substrate for plant Se-enriched cultivation and could lead to the development of new strategies for indoor Se-enriched farming and space Se-enriched farming.