Morphological patterns in Petunia hybrida plants regenerated from tissue cultures and differing by their ploidy

Quantitative variation in seven morphological characteristics (leaf length and width, leaf length/ width ratio, flower, petal and stomata length, and number of chloroplasts in guard cells) were studied in Petunia hybrida plants regenerated from anther tissue culture and belonging to four different classes of ploidy (2n, 2n-3n, 3n-2n, 4n-8n). Results showed that leaf size is not a good characteristic for discriminating between plants of different ploidy - flower and stomata characteristics being more adequate for this purpose. After applying stepwise discriminant analysis the association "chloroplast number - leaf length/width ratio - petal length" was verified to be more appropriate for the discrimination of ploidy classes.