GENOME SIZE VARIATION IN CAJANUS-CAJAN (FABACEAE) - A RECONSIDERATION

A recent investigation of genome size in certain samples of the pigeon pea, Cajanus cajan, indicates values from 1.55 pg to 1.99 pg (1C level ), which is 1.29-fold variation between accessions. In the present ana lysis those of these accessions which had particularly high or low DNA contents in that study were subjected to a reanalysis using propidium iodide and DAPI flow cytometry and Feulgen densitometry. Only minor d ifferences in genome size, not more than 1.047-fold, were found with f low cytometry, and no significant differences were obtained with Feulg en densitometry. The previously reported genome size cannot be confirm ed. It is about half as large and was determined in the present study as 0.825 pg (1C, propidium iodide flow cytometry, Glycine max as stand ard) and 0.853 pg (1C, Feulgen densitometry, Allium cepa and Pisum sat ivum as standards), respectively.