TENTATIVE MODEL ON THE INHERITANCE OF JUVENILITY, SELF-INCOMPATIBILITY AND PARTHENOCARPY

Conventional citrus breeding faces many obstacles such as a prolonged period of juvenility, as well as incompatibility and polyembryony.
Little published information is available on inheritance of juvenility, self-incompatibility, or parthenocarpy.

Satsuma mandarin, known to possess obligatory parthenocarpy, was crossed with 20 different cultivars.
Zygotic hybrids were grown in an insect-proof screen house.
The procedure employed – induction of root restriction, removal of lateral shoots, limb bending, and optimum fertigation – resulted in an apparent reduction in the duration of the juvenile period.
Chances of cross-pollination were very slight.

Data on age of flowering, pollen fertility, fruit set, and number of seeds per fruit were analyzed.
The genetic analyses of the different populations point to the possibility of polygenic inheritance of juvenility, support the self-incompatibility model proposed by Soost (1965, 1969), and suggest that the S allele of Satsuma differs from the two S alleles of Ellendale and one of the S alleles of Clementine.
In addition, we suggest that obligatory parthenocarpy in Citrus depends on three dominant complementary genes.

First International Citrus Biotechnology Symposium

A. Vardi, H. Neumann, A. Frydman-Shani, Y. Yaniv, P. Spiegel-Roy

citrus, Satsuma mandarin, breeding, gibberellic acid

https://doi.org/10.17660/ActaHortic.2000.535.24