Articles
ON THE INHERITANCE OF THE LENGTH OF THE JUVENILE PERIOD IN INTERSPECIFIC PRUNUS HYBRIDS
The E x E hybrids were the latest to flower, with P. avium and P. cerasus inheriting a longer juvenile period than P. fruticosa and P. canescens.
The P x P hybrids start to flower one year from seed with a JP50 of 1.55 years for the group.
The shortest juvenile period is inherited by P. incisa 31, P. nipponica 17, and P. concinna, the longest by P. x hillieri. The E x P and P x E hybrids show a strong maternal inheritance of the length of the juvenile period.
Whereas the course of flowering in the P x E group is nearly identical with the P x P hybrids, the E x P hybrids show a slight acceleration of flowering compared with the E x E group.
Adverse growing conditions in 1969 did not prevent P x P hybrids from flowering after 1 year, but prolonged the juvenile period in the E x E and E x P groups.