Modification of sugar profiles in California adapted apricots (Prunus armeniaca L.) through breeding with Central Asian germplasm

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 F-1 hybrid and two backcross families were evaluated for fruit quality traits and analyzed by HPLC for specific sugar content. The F-1 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 F-1 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 fruit from 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.