Fig. 3.

Influence of after-ripening and controlled deterioration under high or ambient O₂ on viability, dormancy and vigour of sunflower embryos germinated at 10 °C. (A) Viability, as measured by % of normal seedling germination of dormant (left) and non-dormant (right) embryos aged for 0 or 24 d under ambient O₂ or high O₂ (see key). (b) Dormancy and vigour changes, as shown by the time to 25 % germination of the embryo shown in A, n = 4 and 3 replicates of 20 embryos for dormant and non-dormant embryos, respectively ± s.e. Bars labelled with the same letter do not differ significantly at P < 0·05.