Performance of seeds embedded in hydroxyethyl cellulose sheets

Abstract

To prepare “seed sheets”, seeds of cultivar ‘Heinz 1350’ tomato ( Lycopersicon esculentum Mill.) and cultivar ‘Kewpie Orange’ celosia ( Celosia cristata L.) were placed at 1.5 × 1.5 cm spacing in drying solutions of 5% (wt./vol.) hydroxyethylcellulose (HEC, Natrosol 250 LR™) plasticized with 0.35% (vol.vol.) triacetin. After planting in a peat-lite medium, emergence characteristics and seedling shoot weights from unprimed and primed seeds stored in the sheets for 4 weeks were similar to those of seeds not stored in sheets. After 4 weeks of storage in HEC sheets, primed tomato seeds (−1 MPa polyethylene glycol, 15°C, 1 week) gave earlier seedling emergence and greater seedling shoot fresh weight than unprimed seeds stored for 4 weeks in HEC sheets. Whilst 200–1600 mg N l −1 in the HEC had no effect on tomato seedling emergence or shoot fresh weight, 1600 mg N 1 −1 reduced the rate and synchrony of celosia seedling emergence. “Seed sheets” prepared from HEC provided a rapid and practicable means of sowing many seeds at predetermined spacing.