Figure 1.

A, Barley seeds. Developmental stages considered in this work are as follows: 4 to 7 DPA, early development; 10 to 25 DPA, maturation; and 25 DPA up to dry seed (ds), desiccation (González et al., 1998). B and C, Time course of PEPC activity in crude extracts from seeds at different development stages and dry seeds. PEPC activity was assayed in nondesalted crude extracts from whole seeds at optimal pH (8.0), 2.5 mm PEP, and 30°C. PEPC activity was expressed on a per seed basis (B) or on a protein basis (C). Results are means of three independent experiments.