Seed treatments to advance greenhouse establishment of beet and chard microgreens

Abstract

SummarySeed treatments to advance the establishment of table beet or chard (Beta vulgaris L.) for greenhouse microgreen production were examined. While germination percentage was little affected, appreciable germination advancement in both crops was achieved using all seed treatments of matric priming (–1 MPa at 12°C for 6 d in fine vermiculite) or various soaks (water, 20°C for 48 h; hydrogen peroxide, 0.3% at 20°C for 48 h; hydrogen chloride, 0.3 M at 20°C for 2 h; or sodium hypochlorite, 4% at 20°C for 3 h). The most pronounced seedling emergence advancement, however, was gained by germinating seeds in fine grade vermiculite and sowing the germinated seed plus vermiculite mixture. No additional advancement in seedling emergence or growth was achieved by priming or soaking the seeds in hydrogen peroxide before germinating the seeds in the vermiculite. Germinating the seeds in shallow (c 4 cm deep) vermiculite (150% initial water, c 1 seed :3 vermiculite dry weight ratio, 27°C) for 2 d (table beet) or 3 d (chard) resulted in 0.33-fold and 2.79-fold greater shoot fresh weight, respectively, at 11 d after planting than was achieved by sowing untreated seeds.