Table I.
Concentration of several organic constituents in the endosperm liquid
| Av. FW/embryo | 0.2 mg | 0.4 mg | 1.2 mg | 2.8 mg | 3.6 mg |
|---|---|---|---|---|---|
| mm | |||||
| Glc | 129 ± 9 | 101 | 59 | 40 ± 11 | 25 |
| Suc | 9 ± 8 | 20 | 78 | 76 ± 5 | 88 |
| Sugarsa | 276 | 242 | 274 | 232 | 226 |
| Malate | 6 ± 0.1 | 7 | 10 ± 1 | 15 | 15 ± 2 |
| Gln | 20 ± 1 | – | – | 36 ± 1 | – |
| Asn | – | – | 1 | – | |
| Glu | 5 ± 1 | – | – | 11 ± 1 | – |
| Ala | 5 ± 1 | – | – | 7 ± 1 | – |
| Sum of measured amino acids | 39 | – | – | 70 | – |
Endosperm liquid was collected from seeds at different developmental stages (0.2 to 3.6 mg average fresh wt embryo−1). The stage of maximal oil accumulation is represented by 2.8 and 3.6 mg fresh wt (Murphy and Cummis, 1989). Gln, Glu, and Ala were the predominant amino acids with all other amino acids in concentrations less than 3 mm. sd is given with three replicates.
a
Sum of Glc, Fru, and Suc. Suc was converted to hexose equivalents. According to thin-layer chromatography (TLC) analysis, the concentration of Fru was assumed to be equal to the Glc concentration.