GENOME SIZE VARIATION IN PISUM-SATIVUM

Pisum sativum L. is one of the plant species where infraspecific genom e size variation, up to 1.29-fold between cultivars, has been reported . The present investigation deals with a Feulgen cytophotometric analy sis of this phenomenon in 25 wild accessions, landraces, and cultivars of widely different geographic origin. Differences between accessions were maximally 1.054-fold in single experiments but proved to be nonr eproducible upon repeated measurements. Seedlings of the same accessio n often differed significantly, up to 1.056-fold, but values from root and shoot tips in one individual were not significantly correlated, i ndicating the absence of true genome size variation between plants. Up on calibration against Allium cepa a 1C value of 4.42 pg is estimated for Pisum sativum. Altogether the data suggest that, contrary to the d ivergence in the literature data and recent reports on DNA content var iation, the pea has a stable genome size.