Priming-induced nuclear replication activity in pepper (Capsicum annuum L) seeds. Effect on germination and storability

Using flow cytometry, we observed that priming treatments in PEG solutions might induce DNA replication in the embryo root tips of pepper seeds. Under the same osmotic condition the amount of induced DNA synthesis was proportional to the length of the treatment and its effectiveness in improving seed performance, as measured by the reduction in mean germination time (MGT). However, different osmotic treatments might exert the same effect on MGT while inducing a different amount of nuclei to enter the synthetic phase. The activation and progress in DNA synthesis during priming, therefore, appear to be strongly influenced by the osmotic conditions and length of the treatment. Osmoconditioning of controlled deteriorated seeds exerted various effects on seed germination, depending on seed deterioration. Under the same treatment, the amount of priming-induced DNA synthesis was lower than in unaged seeds or it was not induced at all. Osmotic treatments considerably lowered seed tolerance to adverse storage conditions as compared with untreated seeds. However, seeds in which DNA replication was induced by priming were more sensitive to controlled deterioration than seeds in which priming did not induce nuclei to enter the synthetic phase.