HOMOZYGOUS VERSUS HETEROZYGOUS SELF-COMPATIBLE SEEDLINGS IN AN ALMOND BREEDING PROGRAMME

No self-compatible homozygous almond cultivars have been reported so far.
It is unclear if they are inferior to heterozygotes (and consequently they were not selected), or simply not yet detected.
To investigate this, the self-compatibility genotype, homozygous or heterozygous, was determined by stylar ribonuclease assay in a population of 241 almond trees obtained by self-fertilization of self-compatible selections.
The resulting zymograms showed that 129 of the seedlings were homozygous and 112 heterozygous.
For three years the differences existing between these two types of self-compatible individuals were analysed with respect to 16 agronomic characteristics.
In general, there were no important differences between the two classes, both showing a low degree of productivity, probably as a result of their inbred origin.
Some selected homozygous individuals were used in crosses, which were planned so as to ensure the self-compatibility of 100% of the descendants and thus eliminate the laborious task of testing the seedlings for self-compatibility.

III International Symposium on Pistachios and Almonds

F. Dicenta, E. Ortega, P. Martínez-Gómez, Bošković, K.R. Tobutt

Almond breeding, self-compatibility, Prunus dulcis, stylar ribonucleases, inbreeding depression.

https://doi.org/10.17660/ActaHortic.2002.591.30