Articles
MUTATION BREEDING OF PETUNIA
Short characteristics of the most interesting mutants are given.
The allotetraploid petunias of the superbissima group are of great interest for plant breeders.
The petunias are characterized by very big flowers, thick and strong stems and they are more resistant to bad weather conditions.
They have, however, such negative characters as lower blooming intensity, lower seed setting ability and they form tall plants with small number of branches.
Aiming at improvement of the petunias, the mutation induction program was started in 1963. An old variety known as "purpurea" with tall single stems and purple flowers was taken for experiments.
Seed samples of 1000 seeds each were treated with thermal neutrons at Brookhaven National Laboratory twice, in 1963 and 1967, using thermal neutron flux of 2.9–3.4 x 109 nth/cm2.sec. and irradiation time of 30–60–90–120 minutes.
In the M1 generation some interesting chlorophyll as well as morphological changes were observed, which were described elsewhere (Muszynski, 1964, 1967, 1968, 1975).
Selection of mutants in the subsequent generations yielded many mutants, some of which are very valuable for further breeding of the superbissima petunias.