Investigation of Different Selenium Sources and Supplying Methods for Selenium Enrichment of Basil Vegetable (A Case Study under Calcareous and Non-calcareous Soil Systems).

Background: Selenium (Se) is a crucial component of selenoaminoacids and selenoproteins. Therefore, Se-enriched agricultural products can reduce health complications induced by Se deficiency.

Objective: This research was carried out to investigate the effects of Se bio-enrichment on Basil grown in calcareous and non-calcareous soil systems and also to evaluate the changes in Se concentration in the soil after harvesting.

Methods: The experiment executed in two calcareous and one non-calcareous soil systems, and different Se application methods (control, soil application, seed inoculation, foliar application, and soil + foliar application) were administered. Selenobacteria, a plant growth-promoting rhizobacteria (PGPR), derived from the soil was used as a biofertilizer, compared to the other Se sources.

Results: The results showed that both soil types and the methods of Se application had significant effects (P ˂ 0.01) on root and shoot dry weights and concentrations of P, K, Zn, Fe, and Se in both of the root and shoot. Shoot dry weight of plants treated with foliar Se was maximum in the calcareous soil. Compared to the control treatment, foliar application of Se increased shoot Se content in both calcareous and non-calcareous soils by 242% and 204%, respectively. Furthermore, the increase in shoot Se concentration in calcareous soil induced by Se application increased the concentration of other nutrients in the shoot and root. Plant growth parameters and concentrations of nutrients were significantly increased by using selenobacter inoculum.

Conclusion: The application of Se-containing compounds can improve vegetable quality. Considering the daily requirement of the human body for minerals and nutrients, enriching basil with Se can play an important role in community health. Moreover, some patents have reported the effectiveness of endophyte bacteria.