DNA replication is a late event during maize germination and DNA polymerase activity increases as germination proceeds. A replicative a-type DNA polymerase has been purified from maize seeds (DNA polymerase 2) and has been shown to be a multisubunit complex [Coello, P., Rodriguez, R., Garcia, E. Phosphate incorporated into the different polypeptides in the 11 -14-h period remained stable for at least the next 10 h (to 24 h of germination), the period of maximal enzyme activity. However, DNA polymerase 2 processivity was very similar in freshly prepared 3-h and 24-h enzymes, and no evidence was found that polymerase activity was modified by in vitro phosphorylation. The significance of these results is discussed.