Priming Brassica Seed to Improve Emergence under Different Temperatures and Soil Moisture Conditions1
- S. C. Rao,
- S. W. Akers and
- R. M. Ahring2
Germination and emergence of Brassicas under stressful environmental conditions such as adverse soil temperatures and variable soil-water availability appear to be major obstacles in obtaining suitable stand establishment and subsequent forage production. Primed and nonprimed seeds of ‘Purpletop’ and hybrid ‘Tyfon’ turnip (Brassica rapa L.) and ‘Merlin’ kale (B. oleracea L.) were planted and grown in growth chambers at two temperatures (7.5 and 15°C) and four soil moisture levels (-10, -30, -100, and -500 kPa). Primed seeds had been treated in aerated solution of polyethylene glycol 8000 (PEG 8000) at 25°C. Individual primed and nonprimed seeds of each cultivar were planted in boxes containing Dale sandy loam (fine silty, mixed, thermic Pachic Haplustolls) that had been equilibrated at each moisture level. Seedling emergence was counted daily until Day 22 after planting. At 7.5°C, priming increased total emergence by 10 and 21% for Tyfon turnip and Merlin kale, respectively. In contrast, Tyfon turnip was the only cultivar with increased total emergence (11%) at 15°C. Purpletop turnip emergence was not affected by priming at either temperature. Priming decreased the time to attain 50% emergence (ETSO) by 1 to 5 days for Tyfon turnip and Merlin kale at 7.5°C, whereas ETSO for Purpletop turnip increased by 1 to 2 days. At 15°C, priming did not significantly improve the ETSO except for Merlin kale. These results indicate that priming may reduce the risk of poor stand establishment in cold and moist soils and thus allow earlier planting of slow emerging Brassica cultivars to provide needed forage during the spring forage deficit period.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 1987.