Articles
ON THE GENETICS OF FRUIT COLOUR IN SWEET CHERRIES
The following cvs were involved: ‘Alma’, ‘Annabella’, ‘Büttners Rote Knorpel’, ‘Burlat’, ‘Durone Nero II’ mutants, ‘Erika’, ‘Hedelfinger’, ‘Hudson’, ‘John Innes 2420’, ‘2434’, ‘2538’, ‘Kordia’, ‘Lapins’, ‘Merchant’, ‘Mermat’, ‘Merton Heart’, ‘Oktavia’, ‘Regina’, ‘Rube’, ‘Sam’, ‘Stella’, ‘Sunburst’, ‘Ulster’, ‘Valeska’, ‘Van’. Cross combinations were ‘red x red’ and ‘red x blush’ in both directions.
The yellow-red, blushed cvs are often called ‘white’ because of none-coloured juice and flesh.
Clearly yellow cvs were not included.
Progenies did either not segregate at all or give ratios of 1:1 from ‘red x blush’ combinations or 3:1 in ‘red x red’ combinations.
Cultivars as ‘Alma’, ‘Annabella’, ‘Rube’, and probably ‘Kordia’ and ‘Sam’ are homozygous dominant for a gene called ‘A’ by Matthews (1973). Red cultivars segregating are ‘Burlat’, ‘Durone Nero II’ mutants, ‘Erika’, ‘Lapins’, ‘Mermat’, ‘Oktavia’, ‘Regina’, ‘Stella’, ‘Sunburst’, ‘Ulster’, ‘Valeska’, ‘Van’. They can be added to the list of heterozygous cvs.
For ‘Merton Heart’ Matthews data for heterozygosity are confirmed.
There is a close correlation between coloured fruit skin and coloured flesh and juice.
However, there is a low percentage of genotypes with clearly red fruit combined with cream flesh and colourless juice.
We found these plants especially in progenies derived from ‘Büttners’ with ‘Burlat’, ‘Lapins’, ‘Durone Nero’, as well as in ‘Burlat’ x ‘Regina’ and ‘Durone Nero II’ x ‘Valeska’. The percentages varied from 1,9 in ‘Durone Nero II’ x ‘Valeska to’ 12.5 in ‘Burlat’ x ‘Regina’. Wenn studying fruit skin colour these are counted as ‘reds’. For juice colour they belong to the ‘white’ group.
Such seedlings were observed only in progenies derived from heterozygous ‘reds’.
In none of the seedling trees clearly yellow fruit were observed.
This suggests a genetic pattern independent of the ‘A’ gene.