Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 8, 2005
Publication Date: April 1, 2006
Citation: Ledbetter, C.A., Peterson, S.J., Jenner, J.F. 2006. Modification of sugar profiles in California adapted apricots (Prunus armeniaca l.)through breeding with Central Asian germplasm. Euphytica. 148: 251-250 Interpretive Summary: The most common complaint consumers have for California grown apricots is a lack of perceived sweetness. Apricot varieties grown for the fresh market in California generally lack the sugar necessary to satisfy consumers' tastes. Apricots from Central Asia have all the sugar consumers' desire, but their small size makes them undesirable to American consumers. Breeding Central Asian apricots with the varieties grown in California has led to new apricot selections that have both adequate fruit size and elevated sugar content. When we analyzed the specific sugars present in the fruit of the new 'hybrid' selections, we determined that the levels of some of the specific sugars like sorbitol and fructose had changed dramatically from what is normally present in California apricot varieties. The new hybrid apricots have higher levels of specific sugars as compared to normal California apricots, and consumers should be able to detect this elevated sweetness. As a bonus from this breeding project, some of the new sorbitol-rich hybrid apricots can be particularly useful as parents for high quality dried apricots.
Technical Abstract: Central Asian apricot germplasm was used in hybridizations with California adapted apricots to increase Brix levels and improve fresh eating quality. Fruit from parental trees, the F1 hybrid and two backcross families were evaluated for fruit quality traits and analyzed by HPLC for specific sugar content. The F1 hybrid between Central Asian and California adapted apricots was intermediate to its parents in many of the evaluated characteristics and levels of specific sugars. When the F1 hybrid was backcrossed to California adapted apricots 'Lorna' and 'Robada,' the resulting hybrids were diverse in Brix, juice acidity, fruit size and profiles of specific sugars. Glucose: fructose ratios higher that 3.3 were encountered in five of the 22 analyzed seedlings, and fructose: sorbitol ratio ranged from 0.67 to 6.46. Brix and total sugar content correlated significantly with each other and with both sucrose and glucose. No significant correlations existed between sorbitol and any of the other analyzed sugars, nor with Brix or total sugars. The results demonstrated the extent of sugar profile modification possible in California adapted apricots after just two generations of breeding with Central Asian apricot germplasm.