Levels and types of genome variation
Plant genomes can differ from one another in various ways:
The quantity of DNA in the nucleus. This is generally given in picograms (pg), and is sometimes called the C-value. It has not been measured for all plants yet, but in those for which it has, it can vary over 1,000-fold.
The number, size and shape of the chromosomes.
Differences at the sequence level, both in the order of the bases, and in the type and number of different classes of sequence.
