Yield and fruit quality (fruit weight, reducing sugar content, sucrose content and total acids content) were studied in 20 introduced peach cultivars. To evaluate the stability of those characteristics in the agro-ecological conditions of Belgrade surroundings, bi and S2di were applied. ‘Adriana’ had the highest yield and content of reducing sugars, ‘Aurelia’ the highest fruit weight, ‘Pegaso’ the highest sucrose content, and ‘Croce del Sud’ the highest total acids content. Values of bi coeffi cient indicated that ‘Sirio’ had the highest stability of yield ‘Iris Rosso’ the highest stability of fruit weight and content of reducing sugars, ‘Aurelia’ the highest stability of sucrose content, and ‘Emilia’ the highest stability of total acids content. Values of S2di, despite being relatively high, did not show any statistical
signifi cance, which indicates a more signifi cant deviation from regression and unsatisfactory stability of the studied genotypes. The results of the present work confi rm that bi, being a stability parameter, is more important than S2di in heterozygous genotypes, the genotype of a majority of fruit cultivars, therefore of peach itself.
