Two species of Petunia, P. linearis and P. calycina were grown from seed collected in the wild. Their chromosome number (2n = 18) and karotype morphology have been studied. Both species seem to be related to P. parviflora. which found support in peroxidase isozyme data. The three 2n = 18 species differ considerably from the Petunia species with 2n = 14 chromosomes.

Acta botanica neerlandica

CC BY 3.0 NL ("Naamsvermelding")

Koninklijke Nederlandse Botanische Vereniging

H.J.W. Wijsman, J.H. de Jong, & T.M. Pedersen. (1983). On the interrelationships of certain species of Petunia. III. The position of P. linearis and P. calycina. Acta botanica neerlandica, 32(4), 323–332.