Effects of Seed Treatments on the Seedling Emergence, Growth and Yield of Spring-Sown Carrot

Abstract

Carrot seeds, untreated, imbibed, primed, pregerminated and primed + pregerminated, were sown in the field on 28 March, 4 and 11 April. The effects of these presowing seed treatments on seedling emergence, subsequent growth, and yield were examined.
Percentage emergence of seedlings from presowing-treated seeds was not improved. However, mean emergence times of seedlings from presowing-treated seeds were shortened compared to that of untreated seeds. The effect of seed treatments on emergence time of seedlings was in the following order: primed + pregerminated >primed > pregerminated > imbibed. This trend coincides with a previous finding in which plants were grown in pots under low temperature conditions.
Plant dry weight from primed + pregerminated seeds was heaviest of all treatments at early and middle stages of growth, followed by weight from primed seeds. However, plant dry weights from imbibed and pregerminated seeds were not always significantly heavier than those from untreated seeds.
In the second (4 April) sowing, mean root fresh weight and percentage of number of roots at 50 g or heavier from prime + pregerminated and primed seeds were higher than those from other treatments or those from untreated seeds. In the third (11 April) sowing, there were no significant differences in the size and yield of roots among treatments and the control.
The results show that pregermination after priming of seeds improved the yield of carrot when sown in the spring and the temperature is still relatively cold.