(-ABA CONTENT AND LIPID DEPOSITION IN INTERIOR SPRUCE SOMATIC EMBRYOS())

Interior spruce (Picea glauca engelmannii complex) somatic embryos gro wn on 48 mu mol (+/-)-ABA per L over a period of 42 d without transfer underwent precocious germination by 49 d. Those transferred at 28 d t o fresh medium with 48 mu mol (+/-)-ABA continued embryo development u ntil harvested at 56 d; the transfer at 28 d resulted in an increase i n embryo lipid content after 42 d. Somatic embryos grown under this co ndition contained 181.4 +/- 41.2, 116.0 +/- 42.4, and 91.8 +/- 33.6 ng (+)-ABA per mg of lyophilized tissue at 42, 49, and 56 d, respectivel y. By comparison, embryos grown without the transfer at 28 d had 86.8 +/- 25.4 ng (+)-ABA per mg of lyophilized tissue at 42 d, just prior t o precocious germination. After 3 weeks' storage in a drying chamber u nder high humidity, the (+)-ABA content of 56-d-old transferred embryo s decreased to 15.4 +/- 4.4 ng (+)-ABA per mg of lyophilized tissue. T he increased lipid content resulting from embryo transfer and the redu ction in internal (+)-ABA content during storage are factors which wil l contribute to improved conversion of somatic embryos to plantlets.