Table I.

Induction of desiccation tolerance in young embryos

Age	Treatment	WC	DT	Raffinose		R:S
daa		% fresh wt	% germn	μg/embryo	μg/mg fresh wt
16	Freshly harvested	76.4  ± 1.6	0	0	0	–a
	6 d at 90% RH	68.3 ± 1.5	85.5 ± 9.3	9.3 ± 2.9	8.3 ± 2.6	0.33
	6 d at 100% RH	77.1 ± 0.6	12.2 ± 1.6	5.0 ± 0.4	4.5 ± 0.7	0.29
18	Freshly harvested	76.0 ± 0.9	0	0	0	–
	4 d at 90% RH	69.5 ± 0.5	92.0 ± 3.1	11.4 ± 4.4	8.7 ± 3.7	0.35
	4 d at 100% RH	74.5 ± 1.3	11.2 ± 4.3	1.2 ± 0.9	0.9 ± 0.7	0.06

Detached grains aged 16 and 18 daa (approximately 20% and 33%, respectively, of the fresh weight of mature embryos at 32 daa) were kept at 90% or 100% RH for the times indicated. Embryos were removed for the determination of water content (WC), desiccation tolerance (DT) (percentage of germination [germn] after drying to about 7% water content), and raffinose (R) and Suc (S) contents. R:S is expressed as the mass ratio. Values are means ± se of five to six samples (water content and desiccation tolerance) or eight determinations (R and S).

^a–, Not applicable.