CONTRIBUTION TO GENETIC STUDIES IN APPLE

In apple seedlings, tree and fruit traits are assessed using a grading system (usually from 1 to 5). Twenty-two traits are studied ; data being collected with a micro-computer, then managed and interpreted using a computer program (INRA software). Management with a computer allows a detailed study of relationships between traits.

A study dealing with inheritance of fruit skin color is presented ; this is a contribution to add to previous ones (Lespinasse et al., 1984, White et Lespinasse, 1986) and proposes a simple tentative hypothesis to explain the fruit skin colors red and yellow.

To increase our knowledge of apple tree genetics, we are looking for haploid plants by different methods in vivo and in vitro.
Two haploid plants obtained by in vivo gynogenesis, one originating from ‘Topred Delicious’ and the other from ‘Golden Delicious’, were doubled in vitro.
Nevertheless, to evaluate the value of homozygous plants for genetic studies and further for breeding, it is absolutely necessary to obtain several haploid plants ; to achieve this, we have to succeed and be able to routinely develop androgenesis and gynogenesis in vitro.
Some promising results have recently been obtained (Zhang et al., 1987).

Fruit Breeding

Y. Lespinasse, A. Fouillet, J.D. Flick, J.M. Lespinasse, F. Delort

https://doi.org/10.17660/ActaHortic.1988.224.11