Germination, emergence and growth of sunflower (Helianthus annuus L.) in response to osmotic seed priming

The effect of seed priming on germination, field emergence, growth and flowering of three parent lines of sunflower was investigated in Zambia. Priming significantly (P<0.05) reduced the time to 50% germination (TG50) and the time to 50% field emergence (E50). It also significantly (P<0.05) improved both the synchrony of germination (Gs) and the final emergence (Ef). A significant interaction (P<0.05) was found between the genotype of the seed and the priming treatment with respect to germination synchrony (Gs), final germination (Gf) and final emergence (Ef). The emergence synchrony (Es), dry mater accumulation, plant height and flowering were not affected by priming. Indications from this work are that seed priming of the parent lines of sunflower may help to improve the field emergence and establishment of the male lines but it has no influence on the growth and flowering date of the crop. Consequently, seed priming in sunflower may not be a solution to the present obstacle of lack of good flowering synchronisation in hybrid seed production in Zambia.